FIELD OF THE INVENTION

The present invention relates to a device, a system and methods for alerting a driver of a vehicle to the presence of a vulnerable road user in an environment.

BACKGROUND TO THE INVENTION

Road traffic collisions involving vulnerable road users (VRUs) result in numerous deaths and serious injuries each year. VRUs include cyclists, pedestrians, horse riders, motorcyclists and others. Often, accidents involving a VRU and another vehicle (such as a car, van or truck) occur because the driver of the vehicle is unaware of the presence or possible presence of the VRU and/or because the motion of the VRU is unpredictable. In some situations, it may be difficult for a driver to see a VRU in time to take corrective action to avoid collision. In some circumstances therefore, in which detection of a VRU is particularly problematic, there may be an increased risk of collision. For example, in rural areas, trees, road curvature, lack of street lighting and the like may all obscure the presence of a VRU. In urban environments, a VRU may be obscured by buildings, other vehicles and/or may be difficult to identify against a background of, for instance, other moving vehicles, other VRUs, lights and street furniture. VRU detection by drivers, and also in connection with autonomous vehicles and advanced driver-assistance systems (ADAS) is an important factor in reducing the risk of accidents.

It is against this background that the present invention has been devised.

It is an aim of the present invention to overcome at least one problem associated with the prior art whether referred to herein or otherwise.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a warning device for alerting a driver to the presence of a vulnerable road user, the warning device comprising a communication system configured to receive a vulnerable road user identification signal conveying the presence of the vulnerable road user and the warning device being configured to communicate an alert to the driver of the vehicle upon receipt of the vulnerable road user identification signal; wherein the warning device comprises information storage means which stores information relating to a legal and/or administrative status of the vehicle and/or driver.

Preferably, the information storage means stores at least one of: insurance information, tax information, vehicle licensing authority information, and vehicle safety test information. For example, the information storage means may store information issued by, or required by, a vehicle licensing authority, road tax authority, and/or an insurance company or organisation. The information storage means may comprise a national or state vehicle licence authority’s card or disc. The information storage means may store information relating to compliance of the vehicle with law and/or regulations. For example, the information storage means may store a compliance status of a vehicle which indicates whether a vehicle complies with environmental and/or safety regulations.

In other words, the invention can be considered to provide an information storage device comprising information storage means which stores information relating to a legal and/or administrative status of the vehicle and/or driver, further comprising a communication system configured to receive a vulnerable road user identification signal conveying the presence of the vulnerable road user and the warning device being configured to communicate an alert to the driver of the vehicle upon receipt of the vulnerable road user identification signal. In this way the information storage device provides a warning device.

With these arrangements, information which is required to be kept with or in a vehicle is coupled to/integral with the warning device, so that the warning device is also kept in the vehicle. Accordingly, the driver is encouraged to keep the warning device in the vehicle and so the driver will be alerted to the presence of a vulnerable road user. The warning device stores information relating to a legal and/or administrative status of the vehicle and/or driver in combination with means to communicate an alert to the driver of the vehicle upon receipt of the vulnerable road user identification signal. In this way, because it may be mandatory to keep such information with (e.g. mounted in) the vehicle, the present invention provides a device which may be required to be fitted to vehicles within a territory or jurisdiction.

The warning device may provide a compact means for storing such information in a vehicle. For example, by combining information storage means with the warning device, a more compact arrangement is provided than having these separately (for instance, less windscreen space may be occupied).

The warning device of the invention may be arranged to receive a vulnerable road user identification signal from a (pre) existing system for detecting vulnerable road users. In this way, the warning device may be integrated with existing systems.

Preferably, the information storage means comprises an insurance card and/or a tax card and the warning device comprises a card holder for the insurance card and/or tax card. The information storage means may comprise a tax disc or an insurance disc. The information storage means may comprise a physical card made from paper or card and printed with information.

The information storage means may comprise electronic information storage means. In this case, preferably, the information storage means is configured to be read and/or updated remotely. For example, the information storage means may be configured to be read and/or updated by receiving a radio signal (e.g. via a cellular network). The information storage mean may comprise an electronic insurance card and/or an electronic tax card.

Preferably, the information storage means is configured such that, when the warning device is mounted in a vehicle, the information storage means is readable from outside the vehicle. Preferably, the warning device is arranged to be fitted (e.g. retrofitted) to a vehicle. The warning device may comprise mounting means for mounting the warning device in a vehicle. The warning device may comprise mounting means for mounting the device to a windscreen of the vehicle.

The warning device may comprise a power source or power system such that the warning device is a self-contained and/or standalone unit and/or self-powered unit. For example, the warning device may comprise a photovoltaic power source and/or a kinetic energy harvesting device.

Preferably the communication system is configured to communicate a vulnerable road identification signal.

The warning device may comprise: a camera system configured to capture images of the environment and a processor system configured to: receive image data from the camera system; analyse the image data to identify a vulnerable road user. The communication system may be configured to communicate a vulnerable road user identification signal upon the processor system identifying the vulnerable road user. The communication system may be configured to communicate a further/secondary/outgoing/auxiliary vulnerable road user identification signal upon the processor system identifying the vulnerable road user.

According to a second aspect of the present invention there is provided a vulnerable road user warning system for alerting a driver of a vehicle to the presence of a vulnerable road user in an environment, the system comprising: at least one detection device configured to detect the presence of a vulnerable road user; a communication system to communicate a vulnerable road user identification signal conveying the presence of the vulnerable road user in the environment, and a warning device located in the vehicle, wherein the warning device is configured to receive the vulnerable road user identification signal and to communicate an alert to the driver of the vehicle.

The warning device of the system may be a warning device according to the first aspect of the invention. The warning device may receive the vulnerable road user identification signal from the at least one detection device. The at least one detection device may comprise the communication system.

The warning device may be a first warning device located in a first vehicle and the system may further comprise a second warning device located in a second vehicle. The at least one detection device may comprise the second warning device. The second warning device may be according to the first aspect of the invention.

The system may comprise a personal identification device carried by the vulnerable road user and configured to communicate a personal identification signal to a warning device and the warning device may be configured to receive the personal identification signal and to communicate an alert to the driver of the vehicle.

The at least one detection device may comprise: a camera system configured to capture images of the environment; a processor system configured to: receive image data from the camera system; and analyse the image data to identify a road user; a communication system configured to communicate the vulnerable road user identification signal conveying the presence of the vulnerable road user.

The at least one detection device may comprise, or be located in, one or more of the following: a road stud device; an ancillary detection device for mounting to a pre-existing item of street furniture; a road sign device having a display sign. The road stud device may be mounted on a road. The road stud device may comprise a pair of opposed cameras wherein a first camera may be directed in a first direction and a second camera is directed in a second opposing direction.

The road stud device may comprise mechanical power generating means for generating power when a vehicle contacts the road stud device.

The ancillary detection device may comprise a camera system. The ancillary detection device may be arranged to be retrofitted to an item of street furniture. At least part of the ancillary detection device may be arranged to fit in an opening (such as in the top of a post) in an item of street furniture.

The road sign device may comprise an electronic display sign.

The at least one detection device may be mounted on a kerb or pavement, or attached to (dedicated or pre-existing) road furniture such as gantries, poles, posts, (e.g. street lights, telegraph poles etc.).

The warning device may be a first warning device for mounting to a first vehicle.

The system may further comprise a second warning device for mounting to a second vehicle.

According to another aspect of the invention there is provided a road stud device comprising: a first part arranged to be mounted in a fixed position with respect to a road surface; a second part disposed above the first part and displaceable with respect to the first part; power generating means connected to the first part and the second part such that when a vehicle on the road surface contacts the second part, the second part is displaced with respect to the first part and actuates the power generating means, thereby generating electrical power to provide power to the road stud device. The second part may be arranged to protrude above the road surface. The first part may be arranged to be mounted below the road surface. The power generating means may comprise (electro)mechanical power generating means.

The at least one detection device may comprise the road stud device.

According to a third aspect of the invention there is provided a method for communicating the presence of a vulnerable road user in an environment to the driver of a vehicle in the environment, the method comprising: providing at least one detection device configured to obtain sensor data from the environment; obtaining sensor data from the environment using the at least one detection device; determining, from the sensor data, a presence of the vulnerable road user in the environment; and communicating a vulnerable road user identification signal to a warning device in the vehicle, wherein, the warning device is configured to communicate an alert to the driver of the vehicle upon receipt of the vulnerable road user identification signal.

The warning device may be according to the first aspect of the invention.

The method may provide an advance warning alert to the driver of the vehicle by detecting the presence of the vulnerable road user whilst the vulnerable road user is not directly visible to the driver and a direct line of sight between the driver of the vehicle and the vulnerable road user is obscured.

A direct line of sight between the driver of the vehicle and the vulnerable road user may be obscured when the presence of the vulnerable road user is determined and/or when the vulnerable road user identification signal is communicated and/or when an alert is communicated to the driver of the vehicle. In this way, an advance warning may be provided to the driver of the vehicle even when the vulnerable road user is not (directly) visible to the driver.

The method may further comprise providing a vulnerable road user with a personal identification device, the personal identification device being configured to communicate a personal identification signal to the warning device. The warning device may be configured to communicate an alert to the driver of the vehicle upon receipt of the personal identification signal.

The detection device may comprise a camera system. The step of obtaining sensor data from the environment may comprise capturing images of the environment using the camera system. The step of determining the presence of the vulnerable road user may comprise analysing images of the environment obtained by the camera system to identify the presence of the vulnerable road user.

The method may further comprise determining the type of vulnerable road user present. In particular, the step of determining, from the sensor data, the presence of a vulnerable road user may comprise determining the type of vulnerable road user present. For example, the method may comprise distinguishing between a cyclist, pedestrian, motorcyclist, horse and rider, and/or other vulnerable road users. In such cases, the vulnerable road user identification signal may comprise information identifying the type of vulnerable road user. In this case, an alert communicated to the driver may comprise information identifying the type of vulnerable road user. The method may further comprise determining a speed of the vulnerable road user.

The vulnerable road user identification signal may have an effective range, wherein a warning device which is within the effective range of the signal may communicate an alert to the driver and a warning device which is not within the effective range of the signal may not communicate an alert to the driver. The effective range may therefore be considered to be a range within which the vulnerable road user identification signal is ‘effective’ to trigger communication of an alert or warning to a driver. The effective range may be a spatial or temporal range over which the vulnerable road user identification signal is transmitted.

The effective range may define a spatial or temporal range within which the vulnerable road user identification signal causes any (second) warning devices receiving the signal to communicate an alert to a driver.

The effective range may be predetermined. For example, the vulnerable road user identification signal may be communicated (e.g. transmitted) for a predetermined length of time (e.g. following detection of the vulnerable road user). The vulnerable road user identification signal may have a predetermined physical range (e.g. distance/radius). The vulnerable road user identification signal may be transmitted over a predetermined distance.

The effective range may be defined with respect to a location of the detection device which detects the vulnerable road user. The location of the detection device may be predetermined, or may be estimated using GPS data.

The effective range may be defined with respect to a (estimated) location of the vulnerable road user. The location of the vulnerable road user may be estimated based on the location of the detection device which detects the vulnerable road user.

The effective range may be adjusted. The effective range may be continually and/or automatically adjusted. The effective range may be adjusted based on characteristics of the environment. For example, the effective range may be increased in rural environments. The effective range may be adjusted as a function of traffic density. The effective range may increase as traffic density decreases and the effective range may decrease as traffic density increases. The effective range may be adjusted so that a vulnerable road user identification signal is provided to a warning device within a predetermined range of a vulnerable road user. Where the detection device is mounted to a vehicle, the effective range may be adjusted in response to vehicle speed, geographical location of the vehicle. The effective range may be adjusted dependent on traffic density.

The effective range may be adjusted dependent on an estimated distance between a detected vulnerable road user and the nearest vehicle. The effective range may be set based on a geographical location of the vulnerable road user, the detection device, and/or the warning device. For example, the effective range may be reduced in urban environments and/or increased in rural environments. The effective range may be adjusted based on characteristics of a roadway on which the or each vehicle is on. For instance, the effective range may be adjusted based on whether the roadway is a single carriageway or a dual carriageway. The effective range may be adjusted such that an alert is triggered only by warning devices located in vehicles which are at risk of collision with the vulnerable road user (e.g. on the same (or an adjoining) carriageway or roadway as the vulnerable road user.

The effective range may be adjusted depending on a speed and/or heading of the vulnerable road user. Where the type of vulnerable road user is determined, the effective range may be adjusted depending on the type of vulnerable road user detected. For example, the effective range may be increased if the vulnerable road user is a motorcycle, which may be travelling faster than other vulnerable road users. The effective range may be reduced where the vulnerable road user is a slower moving vulnerable road user such as a pedestrian, horse rider, or cyclist.

The effective range of the vulnerable road user identification signal may provide a zone of protection around the vulnerable road user, wherein a warning device in a vehicle within the zone of protection communicates an alert to a driver of the vehicle. In this way, the zone of protection may move with the vulnerable road user through the environment.

A warning device may receive the vulnerable road user identification signal but may not communicate an alert to a driver if the warning device is not within the effective range. The vulnerable road user identification signal may include information relating to the effective range and a warning device receiving the signal may determine (using the information) whether it is within the effective range.

Preferably the vehicle is a first vehicle and the warning device is a first warning device and the method may further comprise the step of providing a second warning device in a second vehicle, the second warning device being configured to communicate an alert to a driver of the second vehicle upon receipt of the vulnerable road user identification signal. The second warning device may be according to the first aspect of the invention.

A direct line of sight between the driver of the second vehicle and the vulnerable road user may be obscured when the presence of the vulnerable road user is determined and/or when the vulnerable road user identification signal is communicated and/or when an alert is communicated to the driver of the second vehicle. In this way, an advance warning may be provided to the driver of the second vehicle even when the vulnerable road user is not (directly) visible to the driver.

The vulnerable road user may not be visible to the driver of the first vehicle and/or the second vehicle.

Preferably the vehicle is a primary vehicle and the warning device is a primary warning device and the method may further comprise the step of providing secondary warning devices in secondary vehicles, the secondary warning devices being configured to communicate an alert to drivers of the secondary vehicles upon receipt of the vulnerable road user identification signal from the primary warning device.

In this case, the effective range may define a spatial or temporal range within which the vulnerable road user identification signal causes second warning devices receiving the signal to communicate an alert to a driver.

The method may further comprise the step of relaying the vulnerable road user identification signal from the first (primary) warning device to the second (secondary) warning device in the second (secondary) vehicle, the second (secondary) warning device being configured to communicate an alert to the driver of the second (secondary) vehicle upon receipt of the relayed vulnerable road user identification signal.

The method may comprise providing a plurality of detection devices in the environment. The method may comprise providing a plurality of different types of detection devices in the environment.

The vulnerable road user identification signal may be communicated from the detection device or from at least one of the plurality of detection devices. The detection device may comprise a warning device. The or each second warning device may be a warning device according to the first aspect of the invention.

The detection device may be mounted to a vehicle (e.g. when the detection device comprises the second warning device).

The detection device may comprise one or more of the second warning devices. The vulnerable road user identification signal may be communicated to the first warning device from the second warning device.

According to another aspect of the present invention there is provided a warning device for use in the method of the third aspect, the warning device being arranged to alert a driver of a vehicle to the presence of a vulnerable road user in an environment, the warning device comprising: a camera system configured to capture images of the environment; a processor system configured to: receive image data from the camera system; and analyse the image data to identify the vulnerable road user, a communication system configured to communicate a vulnerable road user identification signal conveying the presence of the vulnerable road user; and information storage means for storing information relating to a status of the vehicle.

The warning device may comprise a card holder for an insurance card.

The information storage means may comprise an insurance card.

The warning device may comprise a substantially transparent portion to allow inspection of the information storage means. The transparent portion may allow inspection of the information storage means from outside a vehicle in which the warning device is mounted (e.g. through a windscreen).

The information storage means may comprise readable electronic storage means.

The warning device may comprise mounting means for mounting the device to a windscreen of the vehicle. The mounting means may comprise an adhesive region of the device. The mounting means may comprise at least one suction cup.

The warning device may comprise a body. The warning device may comprise a display screen. The display screen may be arranged to display an alert to the driver. The display screen may be pivotally mounted to the body.

The warning device may comprise a speaker for producing an audible alert.

The warning device may comprise a self-contained and/or standalone unit. The warning device may comprise a power system. The warning device may comprise at least one photovoltaic panel. The power system may comprise the at least one photovoltaic panel.

The warning device may comprise a first portion and second portion, the first portion being moveable with respect to the second portion to a closed position. In the closed position, access to the information storage means may be restricted. BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be further described, by way of example only, with reference to the accompanying drawings in which like reference signs are used for like features, and in which:

Figure 1 is a front view of vehicle showing a warning device according to the invention mounted to the vehicle;

Figure 2 is a side view of the warning device of Figure 1 mounted to a windscreen of the vehicle;

Figure 3 is a front view of the warning device of Figure 1 ;

Figure 4 is a rear view of the warning device of Figure 1 ;

Figure 5 is a rear view of the warning device of Figure 1 , showing the device in an open configuration;

Figure 6 is a side view of the warning device of Figure 1 mounted to the windscreen of the vehicle, showing the warning device in an open configuration;

Figure 7A is a schematic plan view showing a VRU in a first example scenario at a first time point;

Figure 7B is a schematic plan view showing a VRU in the first example scenario at a second time point;

Figure 7C is a schematic plan view showing a VRU in the first example scenario at a third time point;

Figure 8A is a schematic plan view showing a VRU in a second example scenario at a first time point;

Figure 8B is a schematic plan view showing a VRU in the second example scenario at a second time point;

Figure 8C is a schematic plan view showing a VRU in the second example scenario at a third time point;

Figure 8D is a schematic plan view of showing VRU in the second example scenario at a fourth time point;

Figure 8E is a schematic plan view showing VRUs in the second example scenario at a fifth time point;

Figure 8F is a schematic plan view showing VRUs in the second example scenario at a sixth time point;

Figure 9 illustrates a method of alerting a driver to the presence of a VRU;

Figure 10A is a cross-sectional view of an embodiment of a road stud device;

Figure 10B is a top view of the road stud device of Figure 10A;

Figure 11 A is a cross sectional view of a further embodiment of a road stud device; and

Figure 11 B is a top view of the road stud device of Figure 11 A.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a system and methods for communicating the presence of a vulnerable road user in an environment to the driver of a vehicle in the environment. The system comprises at least one detection device configured to obtain sensor data from the environment. The presence of a vulnerable road user is determined from the sensor data obtained from the environment. The system comprises a communication system to communicate a vulnerable road user identification signal conveying the presence of the vulnerable road user in the environment, and a warning device for mounting to the vehicle, wherein the warning device is configured to receive the vulnerable road user identification signal from the at least one detection device and to communicate an alert to the driver of the vehicle.

The present invention provides a warning device, a warning system, and methods for alerting a driver of a vehicle to the presence of a vulnerable road user (VRU), as shown in Figures 1 to 11 B.

The warning device is arranged to be mounted in a vehicle, and is arranged to provide information to a driver of the vehicle. In particular, the device is arranged to signal to the driver the presence of a VRU in an environment surrounding the vehicle. The warning device is arranged to detect the presence of a VRU in the environment. The warning device is configured to communicate an alert to the driver of the vehicle upon detection of a VRU. The warning device may be used as part of the warning system (as described further below), or may be used as a standalone device. Accordingly, the device may detect the presence of a VRU directly and/or may receive data concerning the presence of a VRU from other devices forming part of the warning system, including warning devices in other vehicles. The warning device is arranged to communicate with other such warning devices in other vehicles, and/or with other devices in the environment. In this way, the warning system of the present invention is arranged to integrate information from a plurality of sources, so as to provide a reliable system for alerting drivers to the presence of VRUs. The warning system provides a virtual zone (or ‘bubble’) of protection around a VRU. Preferably, the warning device is mounted in a vehicle so that it can be seen by the driver. The warning device is arranged to be fitted (e.g. retrofitted) to a vehicle. In this way, a warning device can be installed in each of a plurality of vehicles, as part of the warning system, as described further below. Figures 1 to 6 show a first embodiment of a warning device 100 according to the invention. Figures 1 , 2 and 6 show the warning device 100 installed in a vehicle 102. In particular, the warning device 100 is mounted to an inner surface 108 of a windscreen 110 of the vehicle 102. The device 100 is mounted in a position so as to be readily visible to the driver (not shown), but without significantly obscuring the driver’s field of view through the windscreen 110. Figure 1 shows a front view of the vehicle 102, with the device 100 mounted on the windscreen 110. In this instance, the vehicle 102 is a left-hand drive vehicle, and so the device 100 is mounted adjacent a side of the windscreen 110 closest to the driver, so as to be clearly visible to the driver. In other examples, the vehicle may be a right-hand drive vehicle. The device 100 may be mounted in other positions on the windscreen 110, such as adjacent a side furthest from the driver, or adjacent a rear view mirror.

Figure 2 shows a cross-sectional view of the vehicle windscreen 110 with the warning device 100 mounted to the windscreen 110. The warning device 100 comprises a first, front side 112 and a second, rear side 114. In use, the front side 112 is arranged to face outwardly, away from an interior 115 of the vehicle 110. In this embodiment, in use, the front side 112 faces an inner surface 108 of the windscreen 110. In this arrangement the front side 112 faces forwards with respect to the vehicle 102, i.e. in the direction of forward travel of the vehicle 102.

Referring additionally to Figures 3 to 5, the warning device 100 comprises a main body 116 and a display screen 118. In this embodiment, the body 116 is generally triangular. In use, the warning device 100 is oriented such that a lower edge 120 of the body 116 extends generally horizontally, and side edges 122 of the body 116 extend upwardly from the lower edge 120 (e.g. in the orientation shown in Figures 1 to 5). In this way, in use, the device 100 resembles a triangular roadside warning sign. In other embodiments however, the device 100 may be generally rectangular, square, circular, or have substantially any shape.

The body 116 comprises a generally triangular front portion 124 and a generally triangular rear portion 126. The front and rear portions 124, 126 of the body together define a housing 128 of the device, having an (at least partly) hollow interior. The front and rear portions 124, 126, are pivotally connected. In this embodiment, the front and rear portions 124, 126 are connected in a clamshell arrangement by hinges 136 disposed adjacent the lower edge 120 of the body 116. In this way, the device 100 may be opened and closed to allow or prevent access to the interior of the housing 128. Figures 1 to 4 show the device 100 in a closed configuration. When in the closed configuration, the rear side 114 faces inwardly, towards the interior 115 of the vehicle 102 in use.

Figures 5 and 6 show the device 100 in an open configuration. The dashed arc in Figure 6 indicates the pivoting motion of the rear portion 126 with respect to the front portion 124 during opening and closing. In this embodiment, the rear portion 126 of the body 116 comprises the display screen 118. In this way, the display screen 118 faces rearwardly towards the interior 115 of the vehicle 102 when the device 100 is in the closed configuration. As can be seen in Figure 5, the device 100 comprises a switch 130. The switch 130 is arranged to control power supply to parts of the device 100. In this embodiment, the switch 130 comprises first electrical contacts 132 disposed on the front portion 124 and corresponding second electrical contacts 134 disposed on the rear portion 126 of the device 100. With this arrangement, when the device 100 is in the closed configuration, the first and second contacts 132, 134 abut one another and are electrically connected so as to complete an electrical circuit for supplying power to parts of the device 100. When the device 100 is in the open configuration, the first and second electrical contacts 132, 134 are moved apart from one another (as shown in Figure 5) and are electrically disconnected so as to switch off power to parts of the device 100. In some embodiments, the device may be configured to prevent or discourage a driver from tilting the display screen away from their field of view. For example, the switch may be actuated when the device is opened or tilted away from a default position, and actuation of the switch may be arranged to trigger an alarm. Actuation of the switch may be recorded in a log as evidence that the device was not used properly, or was powered off, during a particular time period. The device may comprise means for detecting if the device has been removed from the vehicle, such as a switch arranged to be operated when the device is mounted to the windscreen.

The warning device 100 comprises a mounting portion for securing the device to the vehicle 102. In this embodiment, the mounting portion comprises a peripheral adhesive region 138 in the form of a flange which extends outwardly from the body 116 and along an outer edge of the body 116. In this embodiment, the adhesive region 138 extends fully around the periphery of the body 116 adjacent the front side 112 of the body 116. The adhesive region extends in a plane generally parallel to the front side 112 of the body 116. In use, the adhesive region 138 is used to mount the device 100 to the windscreen 110. In some embodiments, the device may be moveably mounted to the windscreen. For example, the device may comprise a hinge, ball and socket connector, or other suitable means (which may be disposed between or connect the mounting portion and the body) for allowing adjustment of the orientation of the device with respect to the windscreen. In further embodiments, the device may be arranged to be mounted to a rear-view mirror of the vehicle, or the device may be integral with a rear-view mirror of the vehicle.

The display screen 118 is arranged to display information to the driver. In this embodiment, the display screen 118 comprises a LED display screen disposed on the rear portion 126 of the body 116. As can be seen in Figure 4, the display screen 118 is generally triangular and is sized and shaped to fit the triangular shape of the rear portion 126. The display screen 118 is arranged to provide a visual alert to the driver. The display screen 118 may display, for example a warning image or graphic representation of a VRU. For example, in Figure 4, the display screen 118 is shown displaying a representation of a bicycle. In some embodiments, the display screen 118 is integral with the rear portion 126 of the body 116 and/or the rear portion 126 is provided by the display screen 118. The warning device may comprise alerting means, which in this embodiment is provided by the display screen 118. In some embodiments, the alerting means may (additionally or alternatively) comprise a speaker or buzzer for producing an audible alert. Vehicle windscreens are typically angled or raked such that the inner surface of the windscreen faces downwardly. Accordingly, the rear side 114 of a warning device 100 mounted to a windscreen 110 may not face directly towards the driver. Where the windscreen rake angle is relatively small (i.e. relatively close to vertical, as can be seen in Figures 2 and 6) the driver may still have an adequate view of the display screen 118. In other vehicles, having a larger windscreen rake, it may be necessary to adjust the angle of the display screen 118 with respect to the windscreen 110 such that the display screen 118 is clearly visible to the driver. In some embodiments therefore, the display screen 118 may be pivotally mounted to the device 100. For example, a hinge (not shown)) may be provided adjacent the top of the device, such that the screen 118 can be pivoted upwardly to face more directly towards the driver, rather than the screen 118 being generally parallel to a raked windscreen and therefore facing downwardly. In some embodiments, a ball and socket arrangement or other suitable pivoting mechanism may be used. With these arrangements, the orientation of the display screen may be adjusted such that the display screen faces towards the driver. The orientation of the display screen may be adjusted with respect to the (front portion of the) body of the device, such that orientation of the display screen may be adjusted to face the driver and the camera system may be positioned or oriented to provide an optimal view of the environment (e.g. through the windscreen).

In further embodiments, the warning device 100 may have a generally triangular cross-sectional side profile, such that a plane of the front side 112 and a plane of the rear side 114 of the device 100 are at angle to one another (i.e. such that a distance (thickness) between the front and rear sides 112, 114 is greater adjacent the lower edge of the device 100 than adjacent an upper end of the device 100). In this way, the rear side 114 (and the display screen 118) may extend in a generally vertical plane whilst the front side 112 may extend substantially parallel to the inner surface 108 of a raked windscreen 110. Variant shapes of the warning device may be provided to fit the rake angle of different windscreens, so as to orient the display screen so that it is clearly visible to the driver. The warning device 100 comprises information storage means arranged to store information relating to a status of the vehicle 102 and/or the driver, such as insurance or tax information, vehicle service history or test information, or permits or vignettes. The warning device 100 is arranged to store such information in a way that allows the information to be read or inspected, for example by a relevant authority. The device 100 may be arranged to allow the information storage means to be read or inspected from outside the vehicle (e.g. through the windscreen). In some embodiments, such information may be stored electronically (e.g. using a chip, disk, memory, or other electronic data storage device) or using an RFID device or similar. In this embodiment, the device 100 comprises a holder 140 for an insurance card 142. The holder 140 is formed by a generally rectangular middle region of the front body portion 124, as can be seen most clearly in Figures 3 and 5. The holder 140 comprises a generally rectangular chamber provided in the hollow interior of the housing 128. At least part of the front portion 124 adjacent the holder 140 is substantially transparent, such that the insurance card 142 can be seen (and therefore inspected) through the front portion 124. With this arrangement, when the device 100 is mounted to the windscreen, the insurance card 142 is held adjacent the windscreen 110 such that the insurance card 142 may be viewed through the windscreen 110. In this embodiment, the insurance card 142 is held in position by part of the rear portion 126 of the body 116, when the device 100 is in a closed configuration. In this way, access to the insurance card is prevented or restricted when the device 100 is in a closed position. In some embodiments, the holder 140 may comprise a slot or sleeve into which the insurance card 142 (or other document or item) may be inserted. It will be appreciated that the information storage means may comprise an insurance card, tax card or similar and that such a card may comprise a printed paper card and/or an electronic or magnetic card or other suitable device. The warning device may comprise an indicator (such as an LED) for indicating a status of the device and/or vehicle (e.g. an insurance status) to facilitate inspection of the device.

In some territories or jurisdictions, it may be required that certain information relating to a status of a vehicle is presented in a particular manner. For example, in France (where vehicles are typically left-hand drive), an insurance card must be displayed adjacent a lower right hand corner of the windscreen. This may have the advantage that the insurance card is at a position furthest from the driver and low enough so as not to obscure the driver’s view through the windscreen. Also, a standardised position allows for easier inspection of such information by authorities. It will be appreciated that where the warning device stores information which is required to be kept with the vehicle, the warning device is not intended to be removed from the vehicle. As will be appreciated from the description further below, the system and method of the present invention may be more effective when warning devices are installed (e.g. retrofitted) in a plurality of vehicles. It is intended that the installation of the warning device in a vehicle may be mandatory or desirable in some jurisdictions. For example, having a warning device mounted in a vehicle may be required for insurance purposes. The information storage means may therefore store information relating to a (insurance) status of the vehicle and/or driver, and may also store information relating to a status of the warning device itself. The status of the device may be required for insurance purposes. For instance, the device may store readable information relating to use of the device (e.g. a log of times during which the device was active or inactive, and/or a log of device location), or diagnostic information to determine whether the device is operating correctly. In this way, both a status of the device and a status of the vehicle (e.g. insurance status) may be read simultaneously (e.g. by a relevant authority). The information storage means may be read and/or updated remotely, for example, by SMS message, where the storage means comprises electronic storage means.

The warning device 100 further comprises a camera system 144, a processor system 146, a power system 148, and a communication system 150, which in this embodiment are disposed in the housing 128.

The camera system 144 is configured to capture images of the vehicle’s environment 106. The processor system 146 is configured to receive image data from the camera system 144 and to process the image data. Together, the camera system 144 and processor system 146 are configured to detect the presence of a VRU in the environment 106 surrounding the vehicle 102. Referring to Figure 3, the camera system 144 comprises at least one camera 152. In this embodiment, the camera 152 faces outwardly from the front side 112 of the device 100, such that the camera 152 faces forwards in use. In this way, the camera 152 is arranged to capture images of the environment 106 through the windscreen 110. The camera 152 is disposed adjacent an upper corner of the triangular body 116.

In some embodiments, the camera system may comprise more than one camera. It will be appreciated that different types of camera may be used. For example, the camera or cameras may comprise a visible light camera and/or an infrared (IR) camera.

The processor system 146 comprises a central processing unit (CPU) (not shown), for example one or more microprocessors. The processor system 146 may further comprise one or more data storage devices. The processor system 146 is configured to receive image data from the camera system 144, and to process the image data to obtain information from the image data. In particular, the processor system 146 is configured to process the image data in order to determine whether an image of a VRU has been captured by the camera system 144. In this way, the processor system 146 may determine the presence of, or a probability of the presence of, a VRU (or multiple VRUs) in the environment 106 around the device 100 (and therefore around the vehicle 102). In some embodiments, the processor system 146 may be configured to identify and differentiate between different types of VRUs. Image processing methods will not be described in detail here, but it will be appreciated that suitable image processing and analysis may be implemented using known computer vision methods. Image processing could also be implemented at least in part by artificial neural network and/or machine learning methods. For example, machine learning methods may be implemented in order to identify VRUs and/or to differentiate different types of VRU. In this way, the device may be configured to be trained (i.e. to ‘learn’) to identify different types of VRUs.

The processor system 146 is also configured to operate the display screen 118. In particular, the processor system 146 is configured to operate the display screen 118 to display a warning image or graphic in the event that a VRU has been detected. The processor system 146 may be configured to cause the display screen 118 to display different information depending on the type of VRU detected. The display screen 118 may show a graphic representation of the type of VRU detected.

In some embodiments (additionally or alternatively), a display screen may be detachable or remote from the device (e.g. connected by a cable, or wirelessly) to provide a satellite or auxiliary display screen (which may be instead of, or additional to the display screen 118). In this way, the display screen may be positioned optimally for visibility by the driver, whilst a main body of the device (e.g. including the camera system) may be positioned to provide a suitable field of view for the camera system.

The communication system 150 is configured to transmit and receive data. In particular, the communication system 150 is configured to transmit data from the device 100 concerning the presence of a VRU in the vicinity of the vehicle 102, and to receive information from other devices (as described further below) concerning the presence of VRUs in the environment 106. Accordingly, the communication system 150 is configured to exchange information with the processor system 146. For example, the processor system 146 may transmit VRU presence data (e.g. derived from processing image data) to the other devices in the system (e.g. a warning device 100 in another vehicle 102). The communication system 150 may be configured to transmit and receive information using short-range radio signals, or over a cellular network, or via Wi-Fi, Bluetooth, or any system suitable for wireless communication. In general, the terms ‘communication system’, ‘communication means’ and related terms used in this specification (in relation to all devices described herein) refer to any system suitable for transmitting and/or receiving information, which may comprise a transponder, radio module, Bluetooth module, GSM module, WiFi module or the like. In some embodiments in which communication occurs via a network, the network may be a distributed network provided by the devices themselves, and/or the network may utilise existing infrastructure such as cellular network infrastructure. It will be appreciated that any of the detection devices and warning devices described herein may be configured to communicate with one another.

The power system 148 comprises a power supply for suppling power to the warning device 100. In the present embodiment, the power system 148 comprises photovoltaic panels 154 and a rechargeable battery (not shown). As can be seen in Figure 3, a pair of photovoltaic panels 154 are disposed adjacent the front side 112 of the device 100, on either side of the holder 140. The photovoltaic panels 154 face forwards, such that in use, they are held against the windscreen 110 so as to be exposed to light (e.g. sunlight) through the windscreen 110. The photovoltaic panels 154 may form part of a front surface of the device 100. The device 100 may be a self- powered, self-contained (standalone) unit. In some embodiments, the power system 148 may be arranged to connect to an external power supply, such as may be provided in a vehicle (e.g. a 12-volt power supply, or USB connection). In some embodiments, the warning device may comprise (additionally or alternatively) a kinetic energy harvesting device. With this arrangement, movement of the device (e.g. as a result of moving/driving of the vehicle, and/or vibrations of the vehicle) may be used to provide power to the device.

In some embodiments, the device may comprise two or more cameras for capturing different views of the environment surrounding the vehicle. For example, the device may comprise a forward-facing camera, and one or more side-facing or rear-facing cameras, where the side-facing camera is arranged to capture an image from a side of the vehicle. These additional cameras may be housed in the device body, or may comprise auxiliary cameras which are in communication with the device, and which are disposed in different locations in or on the vehicle (for instance on a rear-view or side-view mirror). In this way, the device may receive images from a wider field of view, including views which may not be visible to the driver at all times (e.g. blind spots).

In some embodiments the warning device may include a GPS (Global Positioning System) module or system. In this way, the warning device may obtain location data, which may be used and/or communicated with data relating to the detection or identity of a VRU. The warning device may include a thermal detector (e.g. infrared sensor) or detecting the presence of the driver in the vehicle.

In some embodiments, the warning device may not include a camera system. In one such embodiment, the warning device is substantially identical to the warning device of the first embodiment described above, except that the warning device does not comprise a camera system or a processor system configured to receive image data from the camera system and analyse the image data to identify a vulnerable road user.

In this case, the warning device comprises a communication system configured to receive a vulnerable road user identification signal conveying the presence of the vulnerable road user and the warning device is configured to communicate an alert to the driver of the vehicle upon receipt of the vulnerable road user identification signal. Such an embodiment of the warning device may comprise information storage means which stores information relating to a legal and/or administrative status of the vehicle and/or driver.

Referring to Figures 7 A to 8F, the present invention also provides a warning system and methods for alerting a driver to the presence of a VRU 104 in an environment 106 surrounding the vehicle 102. In particular, the system is arranged to provide advance warning to the driver, of the presence, or possible presence, of a VRU 104 which may not (yet) be visible to the driver. Once alerted, the driver may expect the presence of a VRU 104 and may be considerably more likely to notice the VRU 104 than if the driver had not been alerted. Also, once alerted, the driver (or autonomous vehicle) may adapt aspects of their driving (for example, by reducing speed, or changing road position) in preparation for approaching and/or passing the VRU, thereby reducing the risk of collision.

Figures 7A to 8F show examples of a VRU 104 travelling on a road in the environment 106. The road comprises a first roadway 156 and a second roadway 158, which joins the first roadway at a junction 160. The first roadway 156 is curved. In particular, in this example the first roadway comprises an S-bend, or generally sinusoidal portion. The curvature of the first roadway 156 is such that a line of sight along the roadway 156 may be interrupted or obscured by banks, trees, hedges, buildings or the like adjacent the road. A first vehicle 102a is travelling along the first roadway 156 in a first direction (as indicated by a dashed arrow). A second vehicle 102b is travelling along the first roadway 156 in a generally opposite second direction (indicated by a solid arrow).

Figures 7A shows a first example scenario at a first time point. The first vehicle 102a is travelling along the first roadway 156 in the first direction towards the second vehicle 102b. Each vehicle 102a, 102b is provided with a warning device (not shown in Figures 7A to 8F) substantially as described above, capable of identifying a VRU 104 by processing image data obtained from captured images of the environment 106. At this first time point, a VRU 104 is on the first roadway 156 between the first vehicle 102a and the second vehicle 102b. The VRU 104 is travelling in the second direction. The VRU 104 is travelling at a slower speed than the vehicles 102a, 102b (as may be the case where the VRU is a cyclist, pedestrian or horse and rider). In some examples, the VRU 104 may not be visible to drivers of either vehicle 102a, 102b at this time point, since the roadway 156 is curved, and a direct line of sight may be obscured by vegetation, banks, or buildings adjacent the roadway. In the present examples, a first line of sight (dotted line 161 ) between the first vehicle 102a and the VRU 104 is interrupted by a building 157. A second line of sight (dotted line 163) between the second vehicle 102b and the VRU 104 is interrupted by trees 159, as shown in Figure 7A. Note that these obstructions (building 157 and trees 161) are omitted from Figures 7B to 8F for clarity.

At a second time point, shown in Figure 7B, the VRU 104 and the first vehicle 102a have moved towards one another, such that the VRU 104 is within a zone of detection (which in this case is a field of view 162 of a camera system) of the warning device in the first vehicle 102a. The warning device identifies the presence of the VRU 104 from image data obtained by the camera system. The warning device then communicates an alert (a warning message) to the driver. For example, a visual warning may be displayed on the display screen and/or the warning device may produce a sound (e.g. a beep or bell sound). Upon detection of the VRU 104, the warning device also communicates the presence of the VRU 104 to other devices by communicating a vulnerable road user identification signal. In this embodiment, the warning device transmits a relatively short range signal (indicated by the dashed circle around the first vehicle), such as a short-range radio signal or optical signal. In other embodiments, the device may transmit a longer range signal, and/or may communicate with other devices via a communications network, such as a cellular network. The warning device may communicate the VRU identification signal immediately upon detection of a VRU and/or may store information relating to detection of the VRU and/or may communicate the signal at a later point in time. The warning device may release or communicate a VRU identification signal when another warning device is within a predetermined range. The warning device may release or communicate a VRU identification signal in response to an external signal (e.g. an inquiry signal), for example transmitted by another warning device.

Referring additionally to Figure 7C (showing a third time point), as the first vehicle 102a and the second vehicle 102b travel toward one another along the first roadway 156, the second vehicle 102b moves within range of the signal transmitted by the warning device in the first vehicle 102a. In this way, the warning device in the second vehicle 102b may receive the signal sent by the warning device in the first vehicle 102a. Subsequently, the warning device in the second vehicle 102b then communicates a warning signal (alert) to the driver of the second vehicle 102b. With this arrangement, the driver of the second vehicle 102b is alerted to the presence of the VRU 104 on the road ahead. The driver of the second vehicle 102b may therefore be alerted to the presence of the VRU 104 ahead before the VRU 104 enters a field of view or line of sight of the driver. For example, (as shown in Figure 7C) the VRU 104 may be hidden by the road curvature between the second vehicle 102b and the VRU 104. Accordingly, the driver of the second vehicle 102b may anticipate the presence of the VRU 104 as they approach the VRU 104, which helps to reduce the risk of collision. Following receipt of the vulnerable road user identification signal from the warning device in the first vehicle 102a, the warning device in the second vehicle 102b may also communicate a road user identification signal (e.g. a relayed, or secondary signal) for receipt by other devices nearby (e.g. a warning device in another vehicle behind the second vehicle). Once the VRU 104 is no longer detectable by the warning device in the first vehicle 102a (e.g. since the first vehicle 102a has moved past, or away from, the VRU 104), the warning device in the first vehicle 102a may stop sending a road user identification signal after a predetermined period of time. It will be appreciated that signals communicated or relayed in this way may be used to communicate the presence of a VRU to several drivers in an area. In particular, the presence of a VRU may be communicated to drivers in a queue of traffic (e.g. a queue resulting from a slow moving VRU). In this way, drivers in a queue may be notified of the cause of the queue or slowdown, even if they cannot see the VRU. This may help to prevent dangerous overtaking manoeuvres by drivers.

In some examples, information is communicated between warning devices via a network (e.g. a cellular network). The warning device in the first vehicle 102a may also communicate location data (such as GPS data) relating to the location of the first vehicle and/or the location at which the VRU 104 was detected. Accordingly, information relating to the presence of the VRU 104 (e.g. a road user identification signal) may only be communicated to warning devices in vehicles nearby (e.g. within a predetermined radius). In some examples, the presence and/or location of a VRU 104 may be communicated to all devices connected to the network, but may be communicated to trigger a warning device to communicate a warning to a driver only if the warning device (and therefore vehicle) is within a predetermined distance, or time, of the VRU 104. In this way, a road user identification signal may have an effective range. Communication systems described herein may operate using a pre existing central network and/or may use a distributed network provided by components of the system such as the detection devices and warning devices.

The warning device 100 may record the time of detection of a VRU and/or the time of communicating an alert to the driver. The device 100 may store a log of such information. Such information may be of use as evidence (e.g. evidence that a driver was warned of the presence of a VRU) in the event of an incident or collision. This logged information could, for example be considered in conjunction with other vehicle data (e.g. GPS, accelerometer, speed etc.) to determine the action taken by a driver in response to an alert (warning signal) from a warning device. The device may record image data such as images and/or video of the environment. The device may be configured to store images or video of a predetermined length of time. The device may overwrite (e.g. continuously) previously stored image data so that image data from a predetermined prior period is stored. For example, at any given time point, the device may store image data captured during a particular period of time (e.g. 1 hour) preceding that time point.

It will be appreciated that warning devices such as the warning device 100 fitted to vehicles may continue to operate when the vehicle is stationary and/or unoccupied (e.g. parked on a road). In this way, a device in, for example, a parked vehicle may detect the presence of a VRU and communicate a VRU identification signal to warning devices in vehicles currently being driven. A warning device in a stationary vehicle may also receive a signal from warning devices in passing vehicles. This may help to warn an occupant of a stationary vehicle against opening of a vehicle door if a VRU may be approaching. This may help to reduce the risk of collisions caused by opening a vehicle door into the path of VRU. In some embodiments, a warning device in a vehicle may switch off automatically following a predetermined period of time after the vehicle has stopped moving. Thus the warning device may remain switched on for a time after a vehicle has stopped. This may have the advantage of continuing to provide warnings to a driver who has stopped temporarily, or to provide warnings as the driver prepares to leave the vehicle (e.g. if a VRU is approaching). To determine whether or not to switch off the device, the warning device may detect the presence of a driver in the vehicle (e.g. using a thermal detector or infrared sensor).

In some embodiments, the warning device may be configured to display (different) alerts to the driver based on a probability of the presence of a VRU or a probability of collision. For example, the display screen may be blank where little or no probability of collision with a VRU exists. In some environments, (e.g. a busy urban environment) in which a (background) probability of colliding with a VRU may be higher, the device may display a general warning (e.g. a still or slowly flashing graphic of a VRU). This may be the case where multiple VRUs have been detected, or even if the device has not detected a VRU or received a VRU identification signal. This may help to increase driver alertness in higher-risk areas. A general warning/alert may provide a more effective alert to a driver where a plurality of VRUs are present, rather than a plurality of alerts corresponding to the plurality of VRUs. Where a VRU has been detected, the device may display different warnings depending on the proximity of the VRU. For example, as a distance between the vehicle and the VRU decreases, a graphic of a VRU may flash more frequently, and/or be displayed more brightly, and/or an audible warning may increase in intensity. The warning device may be configured to display an estimated distance and/or time between the vehicle and the VRU.

Figures 8A to 8F show a second example scenario of vehicles and VRU(s) on a road in an environment, for a series of time points. In this example, the system comprises a plurality of VRU detection devices which are provided in the environment, in this case along the road. The plurality of detection devices comprises a road sign device 164, an ancillary detection device 166, and first and second road stud devices 168a, 168b. It will be appreciated that the arrangements shown in Figures 8A to 8F are examples useful for illustrating the invention, and that in other examples, the number, type, and arrangement of detection devices, and the road layout, may vary. The detection devices may be positioned along the roadway(s) in specific locations so as to detect a VRU in circumstances in which the risk of an accident is relatively greater. For example, detection devices may be located adjacent, or prior to, curves or bends in the road, junctions, visual obstructions (buildings, greenery etc.) and the like. In detection devices comprising a camera system, the number and/or orientation of cameras in the camera system may be modified according to the road layout. For example, two opposing cameras (e.g. facing at approximately 180°) may be used on a straight section of road, or the angle between the directions in which the cameras face may be adjusted to match the road curvature. 3 or 4 cameras may be used at a T-junction or cross-roads respectively, with one camera facing along each roadway. Each of the detection devices is arranged to detect the presence of a VRU and may be arranged to display a warning signal and/or to communicate with another device. For example, each detection device may be configured to communicate the presence of a VRU (e.g. by communicating a vulnerable road user identification signal) to another device (such as another detection device, and/or a warning device in a vehicle). Accordingly, each of the detection devices comprises detection means and communication means.

In this embodiment, the road sign device 164 comprises an electronic display sign and detection means capable of detecting a VRU. The road sign device 164 is configured to display a warning on the display sign upon detection of a VRU. The road sign device 164 may continue to display a warning (e.g. a flashing graphic depicting a VRU and/or a warning message) for a predetermined period of time following detection of a VRU. The detection means may comprise a camera system and processor system for analysing images obtained by the camera to detect the presence of a VRU. Additionally or alternatively, the detection means may comprise a radar detection system, an electromagnetic detection system (e.g. an induction loop), and/or motion and/or proximity sensors (e.g. infrared, sonic and/or optical sensors). The road sign device may further comprise communication means for communicating a VRU identification signal or other information to another device (e.g. a warning device in a vehicle). The road sign device may comprise means for detecting the presence of a vehicle. Accordingly, the road sign device may only display a warning when there is a vehicle present or approaching. This may help to make the warning more conspicuous and/or reduce power usage.

The ancillary detection device 166 comprises a post-mounted detection device which is arranged to be mounted to a standalone pole or to a pre-existing item of road furniture such as a road sign, street light, speed camera, or the like. The ancillary device 168 is arranged to detect the presence of a VRU and to transmit a signal to a warning device (such as that described herein) in a vehicle nearby. Accordingly, the ancillary detection device comprises detection means for detecting the presence of a VRU. The detection means comprises a camera system and a processor system for analysing image data obtained by the camera system in order to detect the presence of a VRU. In particular, the processor system is configured to analyse image data so as to differentiate between images of different types of VRU. For example, the processor system may differentiate between a cyclist, a pedestrian and a horse rider. The ancillary detection device 166 comprises a communication system and may communicate information (e.g. a VRU identification signal) identifying the presence and type of VRU to another device, such as a warning device. The ancillary detection device 166 may communicate with the road sign device 164 to cause the road sign device 164 to display a warning. In some embodiments, the ancillary detection device may be arranged to be mounted in an opening, such as a circular opening as may be found at the top of a pole supporting a road sign. The ancillary detection device may comprise a body shaped such that at least part of the body fits into such an opening (e.g. a generally cylindrical body). The device may comprise a generally dome shaped cap portion (e.g. a glass dome) which houses (at least part of) the camera system. The position of the ancillary detection device mounted to a pole or post adjacent the road may help to provide a better field of view to the camera system.

The road stud device 168 comprises a road stud which is arranged to be mounted on or in a road surface. A first embodiment of the road stud device 168 (not shown in detail) comprises detection means in the form of a camera system and a processor system for analysing image data obtained by the camera system, in order to detect the presence of a VRU. The processor system of the road stud device 168 may also be configured to differentiate between different types of VRUs. The camera system of the road stud device 168 may have a relatively wide field of view and/or more than one camera, so as to be able to detect a VRU travelling in either direction along a road. The road stud device 168 further comprises communication means for communication with other devices. In particular, the road stud device may be arranged to communicate with a road sign device such as the road sign device 164. The road stud device 168 may transmit a signal to a road sign device upon detection of a VRU, which may cause the road sign to display a warning signal to approaching drivers. The road stud device 168 may communicate with other road stud devices 168 at different positions along the road. In this way, a VRU identification signal may be propagated along a road by communication between adjacent road stud devices 168. The road stud device 168 is also configured to communicate with the warning device (e.g. directly by a suitable wireless communication method, or via a network). In some embodiments, the road stud device 168 may be arranged to provide a visual signal upon detection of a VRU. For example, the road stud device 168 may light up and/or flash/and or change a colour of emitted light to indicate the presence of a nearby VRU.

In use, a plurality of road stud devices 168 may be spaced apart along a roadway. For example, road stud devices 168 may be spaced at regular intervals along a roadway (e.g. spaced by a regular distance, or at distances which correspond to regular time periods according to a typical speed of a vehicle on the roadway). Road stud devices 168 may be placed in locations at which the risk of collisions may be greater, such as adjacent junctions, areas with higher traffic flow, and/or areas where visibility may be restricted. Road stud devices 168 may be provided on both sides of a road or lane(s) to increase the field of view or area monitored by the road studs 168. Road stud devices spaced apart along a road, in communication with one another and/or another device, may be used to provide a speed check to determine vehicle speed. Road stud devices 168 may be arranged to replace conventional (e.g. reflective and/or illuminating) road studs. For example, a proportion of the conventional road studs on a roadway may be replaced with road stud devices 168. Accordingly, the road stud devices 168 may comprise reflective and/or illuminating elements. In the scenario shown in Figures 8A to 8F, the system comprises two road stud devices 168a, 168b.

Referring to Figure 8A, at a first time point, the first vehicle 102a is travelling along the first roadway 156 in the first direction. The second vehicle 102b is travelling along the first roadway 156 in the second direction. The vehicles 102a, 102b are spaced apart along the first roadway 156 and are travelling toward one another.

First and second road stud devices 168a, 168b are spaced apart on the first roadway 156. The road sign device 164 is located adjacent the first roadway 156, opposite the junction 160. The ancillary device 166 is mounted to a road sign 170 adjacent the second roadway 158. At this first time point, a first VRU 104a is travelling along the first roadway 156 in the second direction. The VRU 104a is located between the first and second vehicles 102a, 102b. At this point, the first VRU 104a may not be visible to the driver of either vehicle 102a, 102b. The VRU 104a has recently passed the first road stud detection device 168a, which has detected the presence of the VRU 104a. Accordingly, at this time point, the first road stud device 168a is transmitting a VRU identification signal (indicated by the dashed circle around the first road stud device 168a). The road stud device 168a continues to transmit the signal for a predetermined period of time (even after the first VRU 104a is no longer detectable by the road stud device 168a). The second vehicle 102b is within range of this signal and so the warning device in the second vehicle 102b receives the signal and communicates an alert to the driver. In this way, the driver of the second vehicle 102b is alerted to the presence of the first VRU 104a on the road ahead, even though the driver may not be able to see the VRU 104a at this point and/or the VRU 104a may not be within a field of view of the vehicle’s warning device. The warning device may transmit a secondary signal (e.g. by relaying the VRU identification signal) upon receipt of the signal from the road stud device 168a. It will be appreciated that, with this arrangement, a driver may be alerted to the presence of a VRU at a time when the driver cannot see the VRU directly and/or the VRU has not yet (or recently) passed any other vehicles. For example, a cyclist travelling on a rural road with little traffic may be detected, and a signal passed from the detection device to a driver approaching the VRU along the road at a later point in time, thus warning the driver of the presence of the VRU ahead. The detection device first detecting the VRU in this scenario need not be a road stud device, but may be any suitable detection device (e.g. of the kinds described herein).

At a second time point, shown in Figure 8B, the second vehicle 102b has moved closer to the first VRU 104a. The VRU 104a is now within a field of view 172 of the warning device in the second vehicle 102b. Accordingly, the warning device in the second vehicle 102b detects the presence of the first VRU 104a and transmits a VRU identification signal. At this second time point, in this example, the first vehicle 102a is not yet within range (as indicated by the dashed circle around the second vehicle) of the signal transmitted from the second vehicle 102b. In other examples however, the signal transmitted by the warning device in the second vehicle 102b may have a longer range, and/or may be transmitted over a network, such that the VRU identification signal conveying the presence of the VRU 104a is received sooner by the warning device in the first vehicle 102a.

It will be appreciated from Figure 8B that a VRU identification signal may be transmitted over an area which includes or encompasses the location of the VRU 104a, and a signal therefore may be transmitted ahead of the VRU 104a. In this way, advance warning may be provided to drivers of approaching vehicles. Each warning device is configured to transmit a VRU identification signal for a predetermined length of time. In some embodiments, the or each warning device may be configured to transmit a VRU identification signal for a length of time based on another condition, such as a distance travelled by the vehicle in which the device is mounted, and/or a distance between the device and the detected VRU.

At a third time point, as shown in Figure 8C, the second vehicle 102b (travelling faster than the first VRU 104a) has passed the first VRU 104a. The second vehicle 102b has moved closer to the first vehicle 102a and so the first vehicle 102a is now within range of the signal being transmitted by the warning device in the second vehicle 102b. A third vehicle 102c is on the second roadway 158, approaching the junction 160. Note that the first VRU 104a is at least partly obscured from view (from the points of view of the first and third vehicles 102a, 102c) by the second vehicle 102b. The third vehicle 102c is also within range of the signal being transmitted by the warning device in the second vehicle 102b. Accordingly, warning devices in the first and third vehicles 102a, 102c receive the VRU identification signal from the warning device in the second vehicle 102b, and communicate a warning to a respective driver. In this way, the drivers of the first and third vehicles 102a, 102c may be alerted to the presence of the VRU 104a, even though the VRU 104a may not be directly visible to these drivers. The warning device in the second vehicle 102b may also communicate the presence of the VRU 104a to other nearby devices (such as, in this example, the road sign device 164 or the ancillary device 166). The warning device in the second vehicle 102b continues to transmit a VRU identification signal for a predetermined period of time as it travels ahead of the VRU 104a along the roadway 156 in the second direction, therefore providing advance warning of the presence of the VRU 104a to the drivers of any vehicles approaching the area in the first direction. The warning devices of the first and third vehicles 102a, 102c (having received a signal from the second vehicle’s device) may also transmit a (relayed) VRU identification signal for a predetermined time as the vehicles move along the roadways 156, 158, therefore providing a moving zone of protection around the VRU 104a.

In some examples, a VRU may be provided with a personal identification device (VRU identification device) or beacon configured to communicate with nearby detection devices and/or warning devices. The personal identification device may communicate a personal identification signal to a detection device and/or warning device, the personal identification signal conveying the presence of the VRU. The signal may also include location information of the VRU. The personal device may transmit a relatively short range signal, continuously, at intervals, and/or when triggered by the VRU. The personal device may transmit a signal in response to a signal (e.g. an inquiry signal) transmitted by a detection device (such as the warning device 100). In this way a detection device may scan the environment to detect a personal warning device. The personal warning device may comprise a smartphone or similar device and may be implemented by an application running on such a device.

For example, a cyclist may have a device mounted to handlebars of the bicycle. A VRU may choose to trigger their personal identification device, for instance in circumstances in which they believe they may be at risk. For example, in the scenario shown in Figure 8C, the first VRU 104a is obscured behind the second vehicle 102b, and so the VRU 104a may choose to trigger a personal identification device in order to transmit a personal identification signal to warning devices in the first and third vehicles 102a, 102c. Regular or continuous transmission of a signal from a personal identification device of a VRU may be useful in other scenarios also, for example in a busy urban environment with many vehicles. Conversely, for a VRU travelling on a quiet rural road, a regular signal may ensure that advance warning is transmitted to any approaching vehicles, as such vehicles may not have received any VRU identification signals from other vehicles or devices, which may be sparse in such environments.

Referring to Figure 8D, at a fourth time point, the first VRU 104a and the second vehicle 102b have moved further along the first roadway 156 in the second direction. The first VRU 104a has now entered a zone of detection (dashed sector) of the road sign device 164 and accordingly the VRU 104a is detected by the road sign device 164. (The zone or region of detection may be a field of view of a camera, or a detection range of a radar system, sensor or induction loop). The road sign device 164 therefore transmits a VRU identification signal conveying the presence of the VRU 104a, which is received by the first, second and third vehicles 102a, 102b, 102c, which are within range of the signal. The road sign device 164 also displays a visual warning, such as an illuminated warning symbol or graphic depiction of a VRU. In some embodiments, the road sign device 164 may identify the type of VRU and display an appropriate graphic indicating the type of VRU. In this example, at this fourth time point, a fourth vehicle 102d enters the environment 106 travelling on the first roadway 156 in the second direction. The first road stud device 168a is no longer transmitting a signal and so the driver of the fourth vehicle 102d is not at this stage alerted to the presence of the VRU 104a ahead.

At a fifth time point, shown in Figure 8E, the VRU 104a has moved further in the second direction and is no longer detectable by the road sign device 164. The fourth vehicle 102d has moved along the first roadway 156 in the second direction and a warning device in the fourth vehicle 102d is now within a range of the signal being transmitted by the road sign device 164. The driver of the fourth vehicle 102d may also be alerted to the presence of the first VRU 104a ahead by the visual signal provided by the road sign device 164. The warning device in the fourth vehicle 102d will also have received a signal from the warning device in the first vehicle 102a, which, travelling in the first direction, has recently passed the fourth vehicle 102d. It will be appreciated that in this example, a VRU identification signal is conveyed to the warning device and/or driver of the fourth vehicle 102d by several different devices. Accordingly, there is some redundancy in the system, which helps to ensure that drivers are reliably alerted to the presence of the VRU 104a. For example, such redundancy may help to reduce the effect of failure of a detection device and/or a warning device.

At this fifth time point, a second VRU 104b approaching the junction 160 on the second roadway 158 enters a zone of detection (e.g. a camera field of view 174) of the ancillary detection device 166. Accordingly, the ancillary device 166 transmits a VRU identification signal, as can be seen in Figure 8F, which shows a subsequent sixth time point. At this sixth time point, the fourth vehicle 102d has moved further in the second direction and is now within range of the signal from the ancillary detection device 166. Accordingly, the driver of the fourth vehicle 102d is alerted (by a warning device in the fourth vehicle 102d) to the presence of the second VRU 104b. The first VRU 104a, having moved further in the second direction, has been detected by the second road stud device 168b, which transmits a VRU identification signal. In this way, if the fourth vehicle 102d continues along the first roadway 156 in the second direction, the driver may also be alerted to the presence of the first VRU 104a, as the fourth vehicle 102d moves within range of the signal from the second road stud device 168b.

The examples and system described above are useful for understanding a method (illustrated in Figure 9) of the present invention of communicating to a driver the presence of a VRU. In Figure 9, optional steps are indicated by dashed lines. In a first step 201 , a detection device (e.g. of the kind described above) obtains data from the environment using one or more sensors (e.g. a camera). In a second step 202 (which may be performed in the detection device or at least partly remotely from the detection device) the collected sensor data is processed to determine the presence of a VRU. In an optional step 208, the type of VRU is determined. In a third step 203, a signal (a vulnerable road user identification signal) conveying the presence (and in some embodiments, the identity or type) of the VRU is communicated to a first warning device in a first vehicle. The communication may be direct, or indirectly via a network. In a fourth step 204, the warning device communicates an alert or warning signal (e.g. a visual, and/or aural signal) to the driver of the first vehicle. In an optional fifth step 205, which may occur simultaneously with the fourth step, a further signal (relayed vulnerable road user identification signal) conveying the presence and/or identity of the VRU, is communicated (relayed) from the first warning device to a second warning device in a second vehicle in the environment. In an optional sixth step 206, the second warning device may then communicate an alert (warning) to the driver of the second vehicle. A further optional step 210 includes communicating a personal identification signal from a personal identification device (for example a device provided on a bicycle, or a smartphone).

In general, the terms ‘communication system’, ‘communication means’ and related terms used in this specification (in relation to all devices described herein) refers to any system suitable for transmitting and/or receiving information and may comprise a transponder, radio module, Bluetooth module, GSM module, WiFi module or the like. Communication between devices may involve one or more intermediate devices. In some embodiments in which communication occurs via a network and/or intermediate device(s), a VRU identification signal may be communicated to a warning device from a network, and/or an intermediate device, rather than directly from a detection device or other warning device.

The warning device 100 described above may be considered to be a detection device. A warning device such as the warning device 100 may be considered to be a mobile detection device. The other detection devices described herein may be considered as static detection devices. However, it will be appreciated that in some embodiments, the other detection devices (road sign device 164, ancillary detection device 166, road stud device 168 and similar devices) may provide a standalone warning system without (or independent of) vehicle mounted warning devices 100, by detecting VRUs and causing the road sign device 164 to display a warning signal to drivers independently of warning devices 100. It will also be appreciated that warning devices in vehicles may similarly provide a standalone system without (or independent of) other warning devices or detection devices (e.g. as shown in Figure 7 A to 7C). Furthermore, the or each warning device may individually help to protect a VRU, by identifying the VRU and alerting the driver, even in the absence of communication from other warning devices or detection devices. Accordingly, some VRU protection may be provided by a single warning device in a situation in which there are no (other) warning devices or detection devices nearby, or for example in the event of failure of a communication system or network. A warning device may enhance or augment the perception or awareness of a driver.

In the examples described above, the or each warning device or detection device may simply communicate the presence of a VRU (i.e. data indicating the fact that a VRU has been detected). In some examples however, a device may communicate additional information, such as a time of detection of the VRU. In this way, a VRU identification signal may be arranged to expire following a predetermined period of time from detection of the VRU. In this way, excessive propagation of signals (e.g. along a queue of vehicles on a road) may be prevented. In some examples, the warning device or detection device may communicate location data associated with the VRU, such as a location of detection of the VRU (e.g. determined using GPS data). For example, a warning device may stop communicating a VRU identification signal once the warning device (and vehicle) have moved a predetermined distance away from where the VRU was detected. Likewise, a VRU identification signal (including associated location data) received by a subsequent warning device (e.g. the second warning device as described above) may not trigger the subsequent warning device to transmit a further signal, or communicate a warning to the driver, if the subsequent device is more than a predetermined distance away from the VRU.

In some examples, a warning device or detection device may obtain additional VRU data, such as the speed and heading of a VRU (e.g. obtained from processing of image data and/or location data). In this way, a more accurate estimate of VRU location may be communicated to other devices in the system. In some embodiments, the detection devices and/or the warning device described herein may determine the speed of a VRU, for example using radar or determining a time take for the VRU to travel between two devices of known location.

A warning device or detection device may determine factors such as a direction of travel, speed, and/or heading of a vehicle and/or VRU. These factors may be determined using e.g. radar, by processing of image or video data, GPS data, or by other suitable methods. In this way, it may be determined (by a detection device or warning device, or remotely) whether a vehicle is approaching a VRU or moving away from a VRU. Accordingly, a VRU identification signal may be communicated if a vehicle is approaching a VRU and may not be communicated if a vehicle if moving away from a VRU. In some cases, a VRU identification signal may be communicated, and an alert may be communicated to a driver of a vehicle if the vehicle is approaching a VRU and may not be communicated if the vehicle if moving away from a VRU.

In some embodiments, a vehicle warning device or detection device may determine a speed of approach or closing speed of a vehicle relative to a VRU. For example, a vehicle speed and heading (e.g. derived from GPS data, or radar) may be compared with speed and heading of the VRU. Speed and heading may be determined using data communicated from one or more detection devices. A warning relating to the speed of approach may be communicated to the driver, in addition to warning of the presence of the VRU. In some embodiments, a VRU identification signal may be communicated to a vehicle approaching the VRU. In some embodiments, a VRU identification signal may be communicated only to a vehicle approaching the VRU.

As mentioned above, the or each warning device and/or the or each detection device may be configured to communicate a signal for a particular length of time, and/or with a particular range. The vulnerable road user identification signal may therefore have an ‘effective range’, being a temporal and/or physical (geographical) range within which the signal is effective to cause a device receiving the signal to communicate an alert or warning signal to a driver. For example, a device may transmit a signal for a number of seconds or minutes, or alternatively with a range (e.g. radius) of a number of meters or kilometres. In the latter example of a physical radius/range, the signal may include location data of the device sending the signal. In this way, the transmitted location data can be compared with location data indicating the location of a receiving device, and the signal processed accordingly. For example, if the receiving device is within a predetermined distance of the device transmitting the signal, the receiving device may transmit or relay a further/secondary VRU identification signal and/or display a visual warning as appropriate. It will be appreciated that the term ‘communicate’ and related terms used herein refer broadly to any suitable method of conveying or transmitting a signal. For example, a detection device or warning device may actively transmit a signal, and/or may communicate a signal when read, (e.g. probed or pinged) by another device.

In urban areas, in which density of roads and traffic may be greater, vehicle speeds may be lower, and the number of routes which a vehicle may take may be greater, the effective range may be reduced in order to prevent alerts from being communicated to drivers unnecessarily and/or too frequently. In such cases the vulnerable road user identification signal may be relatively short-lived or have a reduced radius. For instance, in an urban area, a vehicle may be relatively closer to a VRU (compared to in a rural area), but the vehicle may be travelling more slowly, and/or may be on a different roadway and thus less likely to encounter the VRU. In contrast, on a highway, or in a rural environment, a vehicle may be further from a VRU, but may be travelling at a higher speed, and/or the number of alternative routes which the vehicle may take may be reduced, such that the vehicle has a greater chance of encountering the VRU. In such environments the effective range may therefore be greater. Also, where traffic density is lower, and/or detection devices are sparser, a greater effective range may help to ensure that the presence of a VRU is conveyed to approaching drivers. For instance, on a road with little traffic and/or where detection devices are spaced further apart, a greater effective range may help to ensure that any approaching vehicles (which may be a considerable distance away) are alerted to the presence of a VRU. Traffic density may be determined from data collected by a detection device, which may detect vehicles as well as VRUs. The effective range may also be adjusted as a function of vehicle speed and/or VRU speed.

The effective range and/or other properties of the vulnerable road user identification signal (or of the relayed road user identification signal) may also be adjusted according to a road layout, type of road (e.g. major or minor road), and/or contiguous infrastructure or topography of the road. For example, on a dual-carriageway, it may be unnecessary or undesirable to communicate a road user identification signal to warning devices in vehicles on both carriageways, if a VRU is only on one carriageway. Accordingly, the system may be configured to communicate such a signal only to warning devices in vehicles which are on the same carriageway or roadway as the VRU. In this way, alerts are not unnecessarily communicated to drivers who need not be alerted to the presence of a VRU (for example because the VRU is on an opposite side of a central reservation or crash barrier to the driver, or on a different roadway altogether). Limitation or adjustment of the (effective range of the) road user identification signal in this way may be implemented by use of location (e.g. GPS) data, image analysis (e.g. by the warning device), or location information communicated from static devices, to determine the location and/or heading of a vehicle (warning device) with respect to different roadways, carriageways etc. A road user identification signal may therefore include such information, and thus trigger an alert only where necessary. For example, an alert may not be communicated to a driver in a vehicle travelling in the opposite direction to a VRU and/or on a distinct roadway from the VRU, such that there is no risk of collision between the vehicle and the VRU, even if the VRU may be visible to the driver of the vehicle. This situation may arise on a dual carriageway for example, where the VRU is on one carriageway and the vehicle is on a different carriageway. The vulnerable road user identification signal could also be limited spatially or directionally, for example by sending a directional signal (e.g. a directional radio signal). It will be appreciated from this example that the effective range need not be symmetrical or uniform with respect to a detection device communicating a VRU identification signal. The effective range may extend further in a first direction away from a detection device than in a second direction away from the detection device (e.g. further in a direction parallel with a direction of travel along a roadway than in a direction perpendicular with the direction of travel along the roadway).

Figures 10 and 11 show further embodiments of road stud devices which may be used in substantially the same way as the first embodiment of the road stud device 168 described above. A second embodiment of a road stud device 300, shown in Figures 10A and 10B, comprises an outer casing 302, an inner casing 304, a cap portion 306 and a housing 308. The outer casing 302, inner casing 304 and housing 308 are arranged to be set into a road surface (indicated by the dashed lines in Figure 10) and covered by the cap portion 306. At least part of the cap portion 306 is arranged to extend over the road surface so as to sit proud of the road surface in use. In this embodiment, the cap portion 306 is generally dome shaped and comprises a substantially transparent material (e.g. glass). Part of the road stud device 300 is arranged to move with respect to the road surface in use (e.g. under the weight of a vehicle or other road user) and this movement is arranged to provide power to the device.

The cap portion 306 is provided with a generally annular flange portion 310 which in this embodiment comprises a resiliently deformable material. The flange portion 310 may be formed of a durable and resilient plastics material (e.g. a polyamideimide). Part of the flange portion 310 extends over the road surface. The cap portion 306 and flange portion 310 are connected to the housing 308. In this embodiment, the housing 308 is moveably mounted in the inner casing 304. The housing 308 comprises a resiliently deformable wall. In this way, when a downward force is applied to the cap portion 306 (e.g. by a vehicle driving over the device 300) the flange portion 310 and housing 308 are elastically deformed such that the cap portion 306 is depressed downwards. The flange portion 310 may comprise a hinge region (e.g. a scored or thinned region) to allow the flange portion to flex under load. The housing 308 has a concertinaed cylindrical wall arranged to deform as the cap 306 is pressed downwards. When the downward acting force is released, the resilient flange portion 310 and housing 308 return the cap portion 306 upwards. In some embodiments the device may comprise a spring against which the cap portion may be depressed. This vertical movement (displacement) of part of the device 300 is arranged to provide electrical power to the device 300 by way of power generating means 312, which may comprise an electric generator (e.g. a dynamo), a piezoelectric device or similar. In other embodiments, the cap portion 306 may be formed of a flexible material and downwards force applied to the cap portion 306 may be arranged to flex the cap portion itself so as actuate power generating means. For example, the cap portion may comprise a substantially transparent flexible plastics material which covers a plunger or button to be depressed by the action of a vehicle. The cap portion 306 may also have a ‘self-cleaning’ function wherein the action of depressing the cap portion 306 causes another part of the device (e.g. part of the flange portion 310) to wipe the surface of the cap portion 306. The ability of the cap portion 306 to be displaced vertically also helps to prevent damage to the device 300 by e.g. a snowplough, or other device scraped across the road surface, as the cap portion 306 will be deflected downwards into the road by such a device.

The device 300 further comprises means for detecting the presence of a VRU and communicating with other detection devices and warning devices such as the warning device 100. The road stud device 300 comprises a camera system 314, a power system 316, a processor system 318 and a communication system 320. In this embodiment, the camera system 314 comprises two generally oppositely facing cameras 322. In this way, the camera system 314 can obtain images in both opposite directions along a roadway. The camera system 314 is arranged to capture images of an environment surrounding the road stud device 300 in order to identify the presence of a VRU. The cameras 322 are disposed adjacent the cap portion so as to capture images through the substantially transparent material of the cap portion. Reflective and/or light emitting elements may be provided adjacent the cap portion to improve the visibility of the road stud.

The processor system 318 is configured to receive image data from the camera system 314 and to process the image data. Together, the camera system 314 and processor system 318 are configured to detect the presence of a VRU in the environment. The communication system 320 is configured to communicate data (e.g. relating to the presence of a VRU) and may comprise a transponder. In this embodiment, the power system 316 comprises the power generating means 312. The power system 316 also comprises a power source 324 (e.g. battery) and a photovoltaic panel 326 mounted in the cap portion. The camera system 314, power system 316, processor system 318 and communication system 320 are contained by (and may be substantially sealed within) the housing 308 and cap portion 306.

The road stud device 300 is arranged to allow at least part of the device 300 to be readily and easily replaced. In particular, the outer casing 302 is arranged to be mounted or fixed in place in the road (e.g. by drilling a hole in the road surface) so that the outer casing 302 is not easily removed or dislodged from the road surface. The inner casing 304, cap portion, 306 and housing 308 are arranged to be releasably secured to the outer casing such that these parts may be removed and replaced when required. The inner casing 304, cap portion 306 and housing 308 may comprise a single sealed unit such that the components within the housing 308 are sealed and protected against the environment (e.g. water ingress). This sealed unit can be secured to (e.g. fitted in, threaded into) the outer casing 302. The inner casing 304 may be threaded into the outer casing 302. The outer casing 302 may be permanently fixed in the road surface. The outer casing 302 may be formed of cast iron, steel or other suitable durable material which can be embedded in the road surface. The inner casing may be formed of a plastics material.

In a variant (not shown) of the road stud device 300, the device is instead arranged to be mounted to a roadside pole or post, such as a pre-existing support pole for a road sign. In this case the variant may not include the outer casing or power generating means. In particular, the device is arranged to be inserted into a top opening of such a pole. For example, the device may be inserted into the circular opening in the top of a cylindrical pole supporting a road sign. In this case, the inner casing and housing are sized to be inserted into the pole and the domed cap portion protrudes above the pole. With this arrangement, the device may be positioned at a height above a road, which, advantageously, may provide a better vantage point (e.g. larger field of view) to the camera system of the device. This position may also increase the exposure of the photovoltaic panel to sunlight. Alternatively, the device could be connected to an existing power supply of a road sign (as may be provided for lighting, etc.). The device may communicate with a road sign device (e.g. as described above) such that the road sign may display a warning when a VRU is detected by the device mounted in the pole. This variant of the road stud device may be considered to be a variant of the ancillary detection device as described above.

In this second embodiment, the outer casing 302 is generally cylindrical and comprises a threaded inner surface 328 arranged to engage with a complementary threaded outer surface 330 of the inner casing 304. The inner casing 304, cap portion, 306 and housing 308 are connected to form a single core (sealed) unit which can be screwed into or out of the outer casing 302. It will be appreciated that other suitable securing means may be used, such as a bayonet fitting, or interference fit.

A third embodiment of a road stud device 350 is shown in Figures 11 A and 11 B. The road stud device 350 is a ‘surface mount’ type road stud arranged to be mounted on a road surface such that substantially all of the road stud device 350 is on or above the road surface. For example, the road stud 350 may be secured to the road surface with and an adhesive and/or by fasteners such as screws driven into the road surface. The road stud device comprises a body 352 which houses components for detecting the presence of a VRU. The body has a generally truncated pyramid or frustum shape. Sloped opposing faces of the body allow traffic to pass more easily over the road stud 350. In some embodiments though, the road stud may be arranged to be mounted on a kerb, or other roadside object, in which case the road stud need not necessarily be able to withstand heavy traffic and may therefore be smaller and/or less robust and thus less costly to manufacture.

The road stud device 350 comprises a camera system 354, a power system 356, a processor system 358 and a communication system 360. In this embodiment, the camera system 354 comprises two generally opposed cameras 362 disposed on generally opposite sides of the body 352. The cameras 362 face outwardly and upwardly away from the device 350. With this arrangement, the camera system 354 can obtain images in both opposite directions along a roadway. The camera system 354 is arranged to capture images of an environment surrounding the road stud device 350 in order to identify the presence of a VRU. Reflective and/or light emitting elements may be provided to improve the visibility of the road stud 350. In this embodiment, the road stud 350 comprises LEDs 364, which in this example are provided on the sloping sides of the body, adjacent the cameras 362.

The processor system 358 is configured to receive image data from the camera system 354 and to process the image data. The camera system 354 is connected to the processor system. Together, the camera system 354 and processor system 358 are configured to detect the presence of a VRU in the environment. The communication system 360 is configured to communicate data (e.g. relating to the presence of a VRU). In this embodiment, the power system 356 comprises a power source 366 (e.g. battery) and a photovoltaic panel 368. The road stud device 350 further comprises mounting apertures 370 for receiving fasteners to secure the device 350 to a surface (e.g. the road surface).

Overall, the present invention provides a system for VRU detection by an in-vehicle device (e.g. a warning device) fitted inside a vehicle mounted against the windscreen. In some embodiments, the in-vehicle device mounted in the vehicle may have functions as follows: a) to be able to function using its own power source, its own camera(s), its own central processing unit (CPU), its owns radio receiver, its own transmitter and its own visual signalling screen and audio speaker; b) to be able to detect a VRU or many of them by camera recognition technology (CRT) (e.g. image recognition, or computer vision) and store and release that information as appropriate; c) to activate a warning to the driver from portable transmitters carried by a cyclist, a horse rider, or any VRU carrying an “activation device” (e.g. a personal identification device) being a manually operated radio transmitter; d) upon receiving a signal, as described in (c) even though the VRU may be out of sight, to immediately visually &/or audibly signal the vehicle driver of a VRU’s close presence; e) as in (b) (storing and releasing information relating to the presence of a VRU) for example when passing another vehicle (e.g. a second vehicle and/or a plurality of vehicles) travelling in the opposite direction or laterally angled vehicle motion, alongside or behind, the in-vehicle device may activate a radio signal; f) the in-vehicle device within the second and/or plurality of vehicles upon activation by the radio signal, may then display a visual and/or audible signal(s) to the driver, alerting them of a nearby VRU, where the VRU may be as yet unseen.

The in-vehicle devices may also send and/or receive radio signals to or from static detectors (road side devices), (e.g. detection devices) which can detect VRUs when they pass; h) the static detectors by use of CRT and their CPU may be able to intelligently detect whether a motorist is heading towards or away from a VRU; i) the static detectors may within a certain time span then send a signal by radio wave to the in-vehicle device within any vehicle approaching the VRU, which then alerts the driver of the vehicle; j) at busy junctions the static detectors may be connected directly or remotely to one or more illuminated fixed warning signs; k) the static detectors may not be an “essential” component but may be an augmenting component of the method of providing a "moving zone of protection" to all VRUs on the road.

The in-vehicle device may contain all the technological parts shown in Figures 1 to 6 of a triangular design unit and the device/unit may be attached to the inside face of a windscreen. The IVD may not be limited to a triangular design and for instance a housing and swivel ball mounting design or other design may be more practicable for cars with severe angles of windscreen rake. The in-vehicle device may have a clear window so that the vehicle &/or driver’s insurance card or Driver and Vehicle Licensing Agency (DVLA) card or disc can be displayed to be visible from the exterior side of the vehicle windscreen within the arc of the windscreen wipers. The in-vehicle device will be able to work just having a plurality of devices on as many other vehicles as the statutory authority, insurance authority or other issuers have so far at any time issued the device to. In some embodiments, a substantial proportion of vehicles, or substantially every vehicle on the road (e.g. in a jurisdiction), may be fitted with an in- vehicle device. In this way the zone of protection for VRUs may be widespread and/or uninterrupted. The in-vehicle device may be required by, and/or beneficial to holders of, vehicle tax and/or insurance policies.

In some embodiments, a system providing a moving "VRU protection bubble” may be enhanced (e.g. less prone to “missing” a VRU) if there are other static detectors, signalling and/or warning devices provided (e.g. detection devices). The static detectors may be based on but not limited to a domed head unit (or other shape units). The static detectors may comprise one or more cameras, battery, power source, CPU, radio receiver and transmitter. In some embodiments, a static detector device may fit into the road pavement and/or kerb but is adapted in its design to also fit into the top of open cylindrical orifice of any standard road sign pole or poles. The static detectors may work as a system on their own of warning drivers of vehicles of the presence of VRUs, by using roadside illuminated signs attached or unattached and possibly some distance away.

In some embodiments, an aim of the invention is also for the warning device to work in conjunction with other systems for detecting VRUs (for example, existing, or future systems, under development now or in the future (e.g. network and media technologies) in facilitating such VRU awareness signalling to be received by the device and transmitted to the driver. Secondly, by being integrated in the insurance card / information storage means holder, the warning device forms (as appropriate depending on the territory) a combined “legal & technical conduit” by which such technologies become universally fitted in “driver's attention view” within a territory’s fleet of vehicles within a period of time (e.g. within the space of a year). Thereafter as the territory’s entire fleet of vehicles has such technology "on board” it is not unreasonably to be expected that accident rates for VRUs will significantly decline.