Technical field

The present disclosure relates generally to a method and a warning system operable in a first vehicle, for notifying a driver about potential hazards on a road travelled by the first vehicle.

Background

It is well-known that traffic accidents involving vehicles are frequently caused by limitations in visibility for the vehicle drivers when a vehicle or pedestrian to be encountered on a road cannot be seen properly. A collision or other incident may happen, sometimes with quite serious or even fatal outcome. For example, the risk for collision or other incident increases when an approaching vehicle is more or less out of sight, e.g. due to blocked view, darkness, bad weather, distracting lights, and so forth, before it is encountered. There may also be a potential risk for collision or other incident when the driver does not notice the other vehicle in time and he/she has not enough time to react properly to avoid an accident.

In order to reduce hazards and incidents on a road travelled by a vehicle, solutions have been proposed to increase the vehicle driver's awareness of potentially dangerous situations on the road involving other vehicles and pedestrians. For example, sensors in the vehicle may be used to monitor the surrounding environment and an alert may be emitted whenever an object, vehicle or pedestrian is detected on the road. Alternatively, external sources may be utilized to obtain information about any obstacles on the road. For example, vehicles and pedestrians may be equipped with radio transmitters which broadcast their presence and parameters of movements in close vicinity. In another example, radars or sensors may be implemented as an infrastructure for a road system such that the radars or sensors broadcast presence of objects detected in close vicinity.

Early warning systems can significantly improve drivers' awareness about potentially dangerous situations. However, the above-mentioned techniques typically generate a large amount of information and notifications which may overwhelm the driver such that these warning systems may have negative impact on the driver's awareness and attention to driving. Ultimately, there is a risk that the driver may either stop paying attention to such warnings and notifications or get distracted by them. It is thus a problem that the above-mentioned warning systems tend to be more or less inefficient in reducing the amount of traffic accidents.

Summary

It is an object of embodiments described herein to address at least some of the problems and issues outlined above. It is possible to achieve this object and others by using a method and a warning system as defined in the attached independent claims.

According to one aspect, a method is performed by a warning system operable in a first vehicle, for notifying a driver of the first vehicle about hazards on a road travelled by the first vehicle. In this method, the warning system receives traffic information related to position and movement of a second vehicle when

broadcasted from the second vehicle or from a road monitor. The warning system then detects a potential hazard on the road caused by or involving the second vehicle based on the traffic information, and detects also that the second vehicle is non-visible to the driver of the first vehicle. Responsive to the above detections, the warning system alerts the driver about said potential hazard. This alerting may be made by emitting an indication in the first vehicle, such as a visual indication, an audio indication and/or a haptic indication, that can be observed by the driver.

According to another aspect, a warning system is arranged to operate in a first vehicle for notifying a driver of the first vehicle about hazards on a road travelled by the first vehicle. The warning system comprises a communication unit configured to receive traffic information related to position and movement of a second vehicle when broadcasted from the second vehicle or from a road monitor. The warning system further comprises a logic unit configured to detect a potential hazard on the road caused by or involving the second vehicle based on the traffic information, and a vehicle detector configured to detect that the second vehicle is non-visible to the driver of the first vehicle. The warning system also comprises an alerting unit configured to alert the driver about said potential hazard.

When employing this method and warning system, it can be avoided that alerts are issued too frequently without any potential hazard such that the driver's attention to them is reduced or even lost altogether. In contrast, the amount of alerts issued due to potential hazards caused by non-visible vehicles, as of the solution described herein, will be limited and more apt and useful to the driver as compared to also issuing numerous pointless alerts for approaching visible vehicles.

The above method and warning system may be configured and implemented according to different optional embodiments to accomplish further features and benefits, to be described below.

A computer program storage product is also provided comprising instructions which, when executed on at least one processor in the vehicle control node, cause the at least one processor to carry out the method described above. Brief description of drawings

The solution will now be described in more detail by means of exemplary embodiments and with reference to the accompanying drawings, in which:

Figs 1 A and 1 B illustrate two exemplary traffic scenarios where two vehicles are blocked from view of each other. Fig. 2 is a scenario illustrating a first vehicle detecting infrared signals emitted from a second vehicle, according to some possible embodiments.

Fig. 3 is a flow chart illustrating a procedure in a warning system, according to further possible embodiments.

Fig. 4 is another flow chart illustrating a more detailed example of how a warning system may operate, according to further possible embodiments.

Fig. 5 is a block diagram illustrating how a warning system may be configured with functional components, according to further possible embodiments. Fig. 6 is a signaling diagram illustrating an example of a procedure when the solution is used, according to further possible embodiments.

Fig. 7 illustrates an example of a traffic scenario where the solution may be employed. Detailed description

Briefly described, a solution is provided in a warning system which can be installed in a first vehicle to be operable for notifying a driver of the vehicle about hazards on a road travelled by the first vehicle. The warning system operates such that traffic information related to position and movement of various other vehicles on the road is constantly received and analyzed by the warning system. Such traffic information may be received when broadcasted from the vehicles themselves or from road monitors which may be installed at certain locations where they can sense presence and movements of any nearby vehicles. The traffic information may also be received over a wireless or mobile network and the solution is not limited to any particular technology or systems for communicating the traffic information.

Thereby, the warning system is able to detect a potential hazard on the road caused by or involving a second vehicle, based on the traffic information. One example is that a potential hazard is detected when detecting that the second vehicle is moving with a certain speed and direction such that it will be

encountered by the first vehicle on the road. In other words, it can be detected that the first and second vehicle will meet at some point. In another example, it may be detected that the second vehicle is parked such that its movement is zero at a location on the road. When detecting such a potential hazard, an alert is issued in the first vehicle in this solution only if it is further detected that the second vehicle is non-visible to the driver of the first vehicle. In that case, a potentially dangerous situation may arise if the driver is unaware of the approaching vehicle and there will not be ample time to discover the vehicle and react once it becomes visible. Otherwise if it is detected that the second vehicle is visible to the driver, no alert will be issued in the first vehicle. This can be accomplished by employing a vehicle detector which is configured to automatically detect whether the second vehicle is visible or not from the first vehicle. For example, a signal or image emitted from the second vehicle may be detectable only by line-of-sight at the first vehicle. The signal may be emitted in the infrared spectrum, i.e. as an infrared signal, which has basically the same propagation properties as a visible signal, i.e. it cannot propagate around corners or the like.

If it is concluded that the approaching second vehicle is visible from the first vehicle by detecting its emitted signal or image, it is thus not necessary to issue an alert and the driver will not be distracted in this case. In this solution an alert will be issued only when needed, i.e. when the approaching second vehicle is non-visible to the driver of the first vehicle. Thereby, the amount of alerts due to potential hazards will be significantly reduced and the alerts will therefore be more apt and useful to the driver as compared to issuing alerts also for approaching visible vehicles.

Figs 1 A and 1 B illustrate two examples where two vehicles are shut out from view of each other. In Fig. 1A, a driver of a first vehicle 100 is unable to see an approaching second vehicle 102 since the line-of-sight view is blocked by a hill, as illustrated by a dashed arrow representing the view from the first vehicle 100. In Fig. 1 B, the driver in the first vehicle 100 cannot see the second vehicle 102 since the line-of-sight view is obstructed by a road curve, again illustrated by a dashed arrow. In this description, the term "non-visible" implies that the second vehicle is blocked or obscured from view relative the first vehicle such that the driver can be assumed to find it difficult or impossible to discover the second vehicle. For example, the second vehicle may be totally blocked from view e.g. by a solid structure or by topography, or may be only partly obscured e.g. by vegetation.

It can be understood that the solution outlined above may be helpful in any traffic situations where a potential hazard caused by or involving a non-visible second vehicle can be detected. For example, the second vehicle may be moving in any direction or may even be standing still at a position blocked or obscured from view.

In this description, the term "vehicle" should further be understood in a broad sense to represent any road-user or traffic participant including cars, lorries, buses, bicycles, trains, or even pedestrians. Throughout this description, the term vehicle could thus be replaced by road-user or traffic participant.

Fig. 2 illustrates an example of how the detection of whether a second vehicle 102 is visible from a first vehicle 100, may be attained. The second vehicle 102 is equipped with plural emitters of infrared signals, denoted 102A. The infrared emitters 102A are placed at the corners of the vehicle 102 to emit infrared signals in virtually all directions from the vehicle 102, as indicated by short arrows. The infrared signals may be emitted continuously or at regular intervals. An identity of the second vehicle 102 may also be encoded in the emitted signals to enable identification of the vehicle 102 once the signals are detected. If the second vehicle 102 is within line-of-sight from the first vehicle 100, as illustrated by a dashed arrow, a vehicle detector 100A on the first vehicle 100 is able to detect the infrared signals emitted therefrom and also to identify the second vehicle 102 based on the signals.

An example of how the solution may be employed in terms of actions performed by a warning system for notifying a driver of a first vehicle about hazards on a road travelled by the first vehicle, will now be described with reference to the flow chart in Fig. 3. This procedure can thus be used to accomplish the functionality described above, and some non-limiting example embodiments will also be described herein. The warning system is thus operably installed in the first vehicle when this procedure is executed and the following actions may be performed by the warning system as follows.

A first action 300 illustrates that the warning system receives traffic information related to position and movement of a second vehicle when broadcasted from the second vehicle or from a road monitor. The warning system may use a suitable communication device for receiving the traffic information over a radio interface. As mentioned above, such traffic information may be received directly from the second vehicle or road monitor, e.g. over a suitable radio link between the first vehicle and the second vehicle or road monitor, or from a serving network node of a radio network which can be used as a means for broadcasting the information. In another action 302, the warning system detects a potential hazard on the road caused by or involving the second vehicle based on the traffic information. For example, the traffic information may indicate that the first and second vehicles will meet at some point, e.g. when travelling in opposite directions on the road, or when the second vehicle travels on another road that will cross the road travelled by the first vehicle, or when the second vehicle is parked on the road. In this context, "potential hazard" means basically that the second vehicle is detected to be present on the road and will be encountered by the first vehicle.

An action 304 illustrates that the warning system further detects that the second vehicle is non-visible to the driver of the first vehicle. In some example

embodiments, the second vehicle may be detected to be non-visible to the driver when a signal or image emitted from the second vehicle cannot be detected by line-of-sight at the first vehicle. It was mentioned above that this detection may be based on infrared light or an image being emitted from the second vehicle which can only be detected through line-of-sight. In another example embodiment, the non-detected signal may thus be an infrared signal emitted from the second vehicle, e.g. in the manner shown in Fig. 2.

Furthermore, an image in this context may be some recognizable pattern or code on the vehicle, such as a number plate or the like, which is emitted by reflection of ambient light or headlight from the first vehicle. An image may also be comprised of a specific detectable color on the vehicle. A specific image, e.g. pattern, can identify the second vehicle as well. It that case, it may be appropriate to brighten the image in some manner to increase its detectability. In another example embodiment, the non-detected signal or image may thus identify the second vehicle.

In a final action 306, the warning system alerts the driver about said potential hazard. Action 306 is thus executed provided that the second vehicle is non-visible to the driver of the first vehicle, as detected in action 304.

Various further embodiments that may be employed in the above procedure will now be described. In one further example embodiment, the potential hazard may be detected when detecting that the second vehicle will be encountered on the road, which may be detected based on position and movement of the two vehicles. In further example embodiments, alerting the driver may comprise emitting an indication in the first vehicle, which indication may comprise at least one of a visual indication, an audio indication and a haptic indication. For example, a visual indication such as a light, symbol or message may be displayed on a dashboard or on a windscreen of the vehicle. An audio indication may comprise a sound signal or a spoken message. A haptic indication may comprise a vibration or impact in some part of the vehicle being sensed by the driver such as the seat or the steering wheel.

In another example embodiment, the indication may be dependent of an

evaluation and quantification of the potential hazard such that a critical situation generates a more intense indication, e.g. brighter light and/or louder sound, than a less critical situation. In this context, the term "critical situation" implies a relatively great hazard while a less critical situation implies a relatively small hazard. A more intense indication may also be that a repeated sound signal or blinking light increases its repetition frequency or changes repetition pattern in a way that catches the driver's attention.

Quantifying the hazard means basically that a "hazard index value" or the like is determined to reflect how serious the situation is. For example, a high hazard index value may indicate a critical situation, such as potential collision and/or accident, whereas a lower hazard index value may indicate a less critical situation. Alternatively, it is also possible to let a low hazard value indicate a great hazard, and vice versa. In another example embodiment, the indication may be emitted only if the quantified hazard, such as the above-mentioned hazard index value, fulfils a predefined threshold condition, otherwise no indication will be emitted. If a low hazard index value is used to indicate a great hazard, and vice versa, an equivalent embodiment would be that the indication is emitted only if the quantified hazard index value is below a predefined threshold. The expression "the quantified hazard fulfils a predefined threshold condition" implies that the situation as such is serious or critical enough to motivate an alert.

In further example embodiments, the evaluation and quantification of the hazard may be performed based on the received traffic information and on any of the 5 current position, condition and movement of at least one of the first and second vehicles. For example, if one or both of the vehicles travel with high speed, a correspondingly high quantification of the hazard may be determined. In another example embodiment, the evaluation and quantification of the hazard may be performed further based on road conditions. Examples of such road conditions o may include presence of frost, ice or snow, the width of the road, and presence of defects such as potholes or the like. In yet another example embodiment, the road conditions may be obtained from one or more road sensors arranged on the first vehicle and/or from the above-mentioned road monitor.

The first vehicle may also be equipped with some suitable means for emitting a 5 signal or image, similar to the second vehicle, to enable other vehicles to detect whether the first vehicle is visible or not from the other vehicle. Thus in another example embodiment, the warning system in the first vehicle may emit a signal which is detectable only by line-of-sight from another vehicle. In yet another example embodiment, an identity of the first vehicle is encoded in the emitted o signal, e.g. in any manner that was exemplified above.

A non-limiting example of how a warning system may operate in a first vehicle will now be described with reference to the flow chart in Fig. 4 which illustrates how the above-described actions 300-306 may be carried out in more detail. A first action 400 illustrates that the warning system receives traffic information related 5 to position and movement of a second vehicle, which information may be

broadcasted from the second vehicle or from a road monitor. This action corresponds to action 300 above. In a next action 402, it is determined whether or not it is possible that the second vehicle can potentially collide with the first vehicle. If not, the second vehicle is not considered to be a potential hazard in this 0 procedure and action 400 can be repeated for another, i.e. next, vehicle. If it is determined in action 402 that it is possible that the second vehicle can potentially collide with the first vehicle, it is further determined in another action 404 whether the second vehicle is visible or not, e.g. by using an infrared detector or an image detector. It should be noted that the second vehicle to be encountered is also identified in the traffic information and it can also be identified by its emitted signal or image, as described above.

If the second vehicle is visible, i.e. its emitted signal or image, in which the vehicle identity is encoded, can be detected, the second vehicle can be considered as no potential hazard at this point and the process may return to action 400 for evaluating the next vehicle. However, if it is determined in action 404 that the second vehicle is non-visible, the warning system further analyses and quantifies the potential hazard, in an action 406. Some examples of how such a potential hazard can be quantified have been described above.

A further action 408 illustrates that the warning system checks whether or not the quantified hazard, e.g. hazard index value, fulfils a threshold condition which in this example means being above a predefined threshold. If the quantified hazard is not large enough to exceed the predefined threshold, the second vehicle can be disregarded at this point and the process may return to action 400 for evaluating the next vehicle. On the other hand, if the quantified hazard is above the predefined threshold, an alert is issued in a following action 410, possibly depending on the hazard index value. The quantified hazard index value thus indicates that the hazard as such is large enough to motivate an alert. Various examples of how the alert may be issued, e.g. as a visual, audio and/or haptic indication, have been described above. The block diagram in Fig. 5 illustrates a detailed but non-limiting example of how a warning system 500 may be structured to bring about the above-described solution and embodiments thereof. The warning system 500 may be configured to operate according to any of the examples and embodiments of employing the solution as described above, where appropriate, and as follows. The warning system 500 is shown to comprise a processor P and a memory M, said memory comprising instructions executable by said processor whereby the warning system 500 is operative as described herein. The warning system 500 also comprises a communication unit 500A with suitable equipment for transmitting and receiving radio signals in the manner described herein.

The communication unit 500A is configured for communication with nodes of a mobile or wireless communication network over suitable radio interfaces using a suitable protocol for radio communication depending on the implementation. This communication may be performed over a radio link to a serving network node, not shown, in a conventional manner which is not necessary to describe here as such in any detail. The solution and embodiments herein are thus not limited to using any specific types of networks, technology or protocols for radio communication.

The warning system 500 comprises means configured or arranged to perform the actions 300-306 and at least some of the actions 400-410 of the flow charts in Figs 3 and 4, respectively. The warning system 500 is arranged to operate in a first vehicle for notifying a driver of the first vehicle about hazards on a road travelled by the first vehicle.

The communication unit 500A in the warning system 500 is configured to receive traffic information related to position and movement of a second vehicle 502 when broadcasted from the second vehicle 502 or from a road monitor 504. This operation may be performed in the manner described above for actions 300 and 400.

The warning system 500 further comprises a logic unit 500B which is configured to detect a potential hazard on the road caused by or involving the second vehicle 502 based on the traffic information. This operation may be performed in the manner described above for action 302 or actions 402, 406 and 408. The logic unit 500B is shown as implemented in or with the processor P.

The warning system 500 also comprises a vehicle detector 500C which is configured to detect that the second vehicle 502 is non-visible to the driver of the first vehicle. This operation may be performed in the manner described above for actions 304 and 404. The warning system 500 further comprises an alerting unit 500D which is configured to alert the driver about said potential hazard. This operation may be performed in the manner described above for actions 306 and 410. The warning system 500 may further comprise an emitter 500E, e.g. an infrared emitter, which is configured to emit a signal which is detectable only by line-of-sight. An identity of the first vehicle is also encoded in the emitted signal.

It should be noted that Fig. 5 illustrates various functional units in the warning system 500, and the skilled person is able to implement these functional units in practice using suitable software and hardware. Thus, the solution is generally not limited to the shown structures of the warning system 500, and the functional units 500A-E therein may be configured to operate according to any of the features and embodiments described in this disclosure, where appropriate.

The functional units 500A-E described above can be implemented in the warning system 500 by means of suitable hardware and program modules of a computer program comprising code means which, when run by the processor P causes the warning system 500 to perform at least some of the above-described actions and procedures. The processor P may comprise a single Central Processing Unit (CPU), or could comprise two or more processing units. For example, the processor P may include a general purpose microprocessor, an instruction set processor and/or related chips sets and/or a special purpose microprocessor such as an Application Specific Integrated Circuit (ASIC). The processor P may also comprise a storage for caching purposes.

Each computer program may be carried by a computer program product in the warning system 500 in the form of a memory having a computer readable medium and being connected to the processor P. The computer program product or memory in the warning system 500 may thus comprise a computer readable medium on which the computer program is stored e.g. in the form of computer program modules or the like. For example, the memory may be a flash memory, a Random-Access Memory (RAM), a Read-Only Memory (ROM), an Electrically Erasable Programmable ROM (EEPROM) or hard drive storage (HDD), and the program modules could in alternative embodiments be distributed on different computer program products in the form of memories within the warning system 500.

The solution described herein may be implemented in the warning system 500 by means of a computer program storage product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions according to any of the above embodiments, where appropriate.

Another example of how the above-described solution may be employed will now be described with reference to the signaling diagram in Fig. 6 which involves a first vehicle 600, a second vehicle 602 and a road monitor 604. It is assumed that the above-described warning system 500 is operably installed in the first vehicle 600, although it is not shown as such. A first action 6:1 illustrates that the road monitor 604 detects vehicles on the road and also registers road conditions, which may be performed on a more or less continuous basis. Another action 6:2 illustrates that the road monitor 604 broadcasts corresponding traffic information, which may likewise be performed on a more or less continuous basis. It is assumed that the road monitor 604 detects the second vehicle 602 and broadcasts corresponding traffic information. Thereby, the first vehicle 600 is able to receive the traffic information about the second vehicle 602, as broadcasted by the road monitor 604.

A further action 6:3 illustrates that the second vehicle 602 emits an infrared signal which may or may not be detected by the first vehicle 600 in the manner described above, schematically illustrated by a question mark. The second vehicle 602 emits the infrared signal more or less continuously such that any nearby vehicle can detect the signal if visible. Another possible action 6:4 illustrates that the second vehicle 602 may also broadcast traffic information related to position and movement of the second vehicle 602, as well as an identification of vehicle 602. This may be performed on a more or less continuous basis as well such that any nearby vehicle can pick up the broadcasted traffic information and detect a potential hazard in the manner described herein. The first vehicle 600 may thus receive the traffic information about the second vehicle 602, either from the road monitor 604 or from the second vehicle 602, and detect a potential hazard on the road caused by or involving the second vehicle 602 based on the received traffic information. Another action 6:5 illustrates that the first vehicle 600 evaluates the potential hazard, e.g. by quantification as described above, and issues an alert if the second vehicle 602 is found to be non- visible by not receiving the infrared signal of action 6:3.

The above procedure may also be executed in a corresponding manner to enable the second vehicle 602 to issue an alert responsive to a potential hazard caused by or involving the first vehicle 600, as follows. An action 6:6 thus illustrates that the traffic information broadcasted by the road monitor 604 is received by the second vehicle 602 to obtain traffic information about the first vehicle 600. In a further action 6:7, the first vehicle 600 more or less continuously emits an infrared signal which may or may not be detected by the second vehicle 602, schematically illustrated by another question mark. The first vehicle 600 may also more or less continuously broadcast traffic information related to position and movement of the first vehicle 600, as well as an identification of vehicle 600, as of action 6:8.

Another action 6:9 illustrates that the second vehicle 602 evaluates the potential hazard involving the first vehicle 600 and issues an alert if the first vehicle 600 is found to be non-visible by not receiving the infrared signal of action 6:7.

Fig. 7 finally illustrates an example of a traffic situation involving a first vehicle 700 and a second vehicle 702 which are about to encounter one another in an area where two roads are crossed. The first vehicle 700 receives traffic information about the second vehicle 702, either broadcasted from the second vehicle 702 or from a road monitor 704 located nearby. A warning system in the first vehicle 700 further detects a potential hazard on the road caused by or involving the second vehicle 702 based on the received traffic information which indicates that the two vehicles are likely to meet in the crossing area.

Just as the first vehicle 700 is about to enter the crossing area, the line-of-sight view of the second vehicle 702 is blocked by a bus 706 being parked adjacent to the crossing area, such that the warning system in the first vehicle 700 does not detect any signal or image emitted therefrom. As a result, a well-motivated alert is issued in the first vehicle 700 since no signal or image emitted by the second vehicle 702 can be detected by the first vehicle 700. Thereby, the driver of the first vehicle 700 is able to notice the alert and drive more cautiously through the crossing area to avoid a collision or other incident. In addition, the driver of the second vehicle 702 may correspondingly receive an alert and drive more cautiously through the crossing area as well.

While the solution has been described with reference to specific exemplifying embodiments, the description is generally only intended to illustrate the inventive concept and should not be taken as limiting the scope of the solution. For example, the terms "warning system", "traffic information", "road monitor", "infrared signals", "visual indication" "audio indication", "haptic indication", "road conditions" and "road sensor" have been used throughout this disclosure, although any other corresponding entities, functions, and/or parameters could also be used having the features and characteristics described here. The solution is defined by the appended claims.