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Title:
TUNNEL MONITORING SYSTEM AND METHOD OF OPERATION
Document Type and Number:
WIPO Patent Application WO/2017/217865
Kind Code:
A1
Abstract:
The present application discloses a method for controlling at least one apparatus (1) moving on a guiding means positioned along a tunnel (3), comprising: receiving a sensor data from the at least one apparatus (1); recognizing a pattern on the received sensor data and inserting an entry on a queue, relating to said recognized pattern; processing at least one target state for an apparatus (1), based on the received sensor data; retrieving the entry from the queue, selecting at least one apparatus (1), with a minimum estimated time to directly achieve the at least one target state, and controlling said selected at least one apparatus (1) to directly achieve the at least one target state.

Inventors:
LERANG GEIR INGE (NO)
Application Number:
PCT/NO2017/050160
Publication Date:
December 21, 2017
Filing Date:
June 15, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
ROXEL AANESTAD AS (NO)
International Classes:
G06K9/00; B25J5/02; E21F17/18
Foreign References:
US20040175040A12004-09-09
JPH09115088A1997-05-02
JP2003013700A2003-01-15
GB2370765A2002-07-10
JP2002157664A2002-05-31
JP2003000746A2003-01-07
JPH09654A1997-01-07
CN103729908A2014-04-16
Other References:
CELENTANO L ET AL: "A robotic system for fire fighting in tunnels", SAFETY, SECURITY AND RESCUE ROTOTICS, WORKSHOP, 2005 IEEE INTERNATIONA L KOBE, JAPAN JUNE 6-9, 2005, PISCATAWAY, NJ, USA,IEEE, 6 June 2005 (2005-06-06), pages 166 - 171, XP010830528, ISBN: 978-0-7803-8945-8
Attorney, Agent or Firm:
HÅMSØ PATENTBYRÅ ANS (NO)
Download PDF:
Claims:
CLAIMS

1. A method for controlling at least one apparatus (1 ) moving on a guiding means (2) positioned along a tunnel (3), comprising:

- receiving a sensor data from the at least one apparatus (1 );

- recognizing a pattern on the received sensor data and inserting an entry on a queue, relating to said recognized pattern;

- processing at least one target state for an apparatus (1 ), based on the received sensor data;

- retrieving the entry from the queue, selecting at least one apparatus (1 ), with a minimum estimated time to directly achieve the at least one target state, and controlling said selected at least one apparatus (1 ) to directly achieve the at least one target state.

2. Method according to the previous claim, wherein processing at least one target state for an apparatus (1 ), based on the received sensor data, comprises:

- processing a velocity of a subject, based on the received sensor data;

- estimating a future state of the subject, based on the processed velocity of the subject; and

- processing at least one target state for an apparatus (1 ), based on the estimated future state of the subject.

3. Method according to any of the previous claims, wherein selecting at least one apparatus (1 ), with a minimum estimated time to directly achieve the at least one target state, comprises:

- processing a minimum estimated time for at least one apparatus (1 ) to directly achieve the at least one target state, based on at least one lookup of a previous target state to which the at least one apparatus (1 ) was controlled to directly achieve.

4. Method according to any of the previous claims, wherein the queue is a priority queue, and each entry in said priority queue has a priority value equal to a pre-defined priority value of a pattern to which said entry relates to.

5. Method according to any of the previous claims, wherein a state comprises a position, a speed, and an orientation.

6. Method according to any of the previous claims, wherein recognizing a pattern on the received sensor data, comprises any of:

- recognizing a vehicle and analysing if said vehicle should be monitored;

- recognizing a fire;

- recognizing a smoke cloud; - recognizing a person walking in the tunnel (3);

- recognizing a person asking for help;

- recognizing a mechanical defect on a vehicle or on the tunnel (3);

- recognizing a static object in the tunnel (3).

7. Method according to any of the previous claims, comprising receiving a sensor data from at least one of:

- a fixed video monitoring system (5);

- an Intelligent Transportation System;

- an Electronic Toll Collection system; or

- a tunnel security system.

8. A tunnel monitoring system, comprising:

- a server comprising a communication means;

- a guiding means (2) positioned along a tunnel (3);

- at least one apparatus (1 ) comprising a driving means (4) for moving on the guiding means (2), at least one sensor, and a communication means for sending sensor data to the server,

where the server is configured to implement the method described in any of the previous claims for controlling the at least one apparatus (1 ) moving on the guiding means (2) positioned along the tunnel (3).

9. Tunnel monitoring system according to the previous claim, wherein the communication means of the at least one apparatus (1 ) is a wireless communication means.

10. Tunnel monitoring system according to any of the claims 8 to 9, wherein the at least one apparatus (1 ) comprises at least one of:

- an image sensor;

- a sound sensor;

- a gas sensor; or

- a temperature sensor.

11. Tunnel monitoring system according to any of the claims 8 to 10, wherein the at least one apparatus (1 ) comprises at least one of:

- a light emitter;

- a sound emitter.

12. Tunnel monitoring system according to any of the claims 8 to 1 1 , wherein the guiding means (2) is positioned at a higher elevation than the floor of the tunnel (3).

13. Tunnel monitoring system according to any of the claims 8 to 12, wherein the guiding means (2) is a rail,

14. Tunnel monitoring system according to any of the claims 8 to 13, wherein the communica- tion means of the server is configured with at least one connection to any of:

- a fixed video monitoring system (5);

- an Intelligent Transportation System;

- an Electronic Toll Collection system; or

- a tunnel security system,

for receiving sensor data.

Description:
TUNNEL MONITORING SYSTEM AND METHOD OF OPERATION

Technical field

The present solution relates to a method for controlling a tunnel monitoring system and to said tunnel monitoring system.

Background

During the last decades, increasingly longer tunnels have been built in order to provide more efficient transport routes, for example road tunnels or railroad tunnels. Such constructions may pass through a mountain or across a fjord, as a subsea tunnel, and may be very deep or very long, for example more than 20 kilometres. Although representing great advantages with respect to providing more efficient transport routes, being more reliable during wintertime with snow storms or replacing ferries for crossing a fjord, it is known that accidents occur regularly and often with serious dangers involved. Particularly serious, are accidents where there are fires breaking out. The dangers from fire incidents in tunnels are observed on any kind of tunnel, such as an industrial tunnel, namely a mining tunnel.

Nowadays, known solutions for monitoring a tunnel provide stationary video cameras, and other sensors, placed 100 meters apart, depending on the road curvature. Signals are relayed to monitoring systems operated from a control room.

These solutions require a high number of cameras and the execution of monitoring activities requires switching between camera feeds regularly. Furthermore, since camera technology develops rapidly, replacing a high number of outdated cameras is costly.

A person skilled in the art will appreciate that the monitoring equipment within a tunnel will require regular maintenance due to the harsh operating environment with pollution such as dust and gases, and also high humidity that may be a problem particularly in subsea tunnels. Such maintenance presents many undesirable hurdles, such as being costly and sometimes requiring the tunnel to be closed for passage, or the traffic to be regulated or stopped while the maintenance is in progress.

Stationary cameras or other sensors being arranged at certain intervals along the tunnel may provide a limited overview of the tunnel. Each camera monitors a designated area of the tunnel. This may not be a problem if an incidence occurs in the designated area. However, if an incident occurs outside or in the outskirts of the designated area, it may be difficult or impossible to detect the incident. An even larger problem occurs if there is smoke or low visibility due to dust, within the tunnel.

General description

The present solution discloses a method for controlling at least one apparatus moving on a guiding means positioned along a tunnel, comprising: - receiving a sensor data from the at least one apparatus;

- recognizing a pattern on the received sensor data and inserting an entry on a queue, relating to said recognized pattern;

- processing at least one target state for an apparatus, based on the received sensor data;

- retrieving the entry from the queue, selecting at least one apparatus, with a minimum estimated time to directly achieve the at least one target state, and controlling said selected at least one apparatus to directly achieve the at least one target state.

The disclosed method effectively controls the at least one apparatus moving on the guiding means based on sensor data of the physical phenomena in the tunnel. Hence, the steps of the method are dependent on the physical occurrences, since they are conveyed by the sensor data.

Some of the physical occurrences that happen in the tunnel are interesting for being monitored and recorded. This motivation can occur, for example, because there is danger involved in the occurrence and there is a need for it to be carefully monitored, or simply because there is some other need to record it. Any motivation to monitor an occurrence in the tunnel is solved by a pattern which is recognized on the sensor data received from the at least one apparatus moving on the guiding means positioned along the tunnel. The person skilled in the art will easily implement the recognition of a pattern, depending on the type of sensor data received, for example by implementing it herself, or by making use of third-party solutions, such as commercial products available for said purpose. For example, if the intention is to recognize the occurrence of any fire breaking out, then the recognition of that pattern can be achieved with any solution, or a combination thereof, for detecting fire. In said case, if the sensor data received is a video signal, then a solution which recognizes fire on a video frame can be used.

After a pattern is recognized from the received sensor data, an entry is inserted on a queue. This queue keeps track of the recognized physical occurrences in the tunnel, and that are still not yet handled. Each entry relates to the recognized pattern, which was the cause for inserting the entry in the queue. For example, this relation is implemented by a field on the entry that identifies the recognized pattern.

A state is understood as at least one parameter for characterizing something in relation to the guiding means. A parameter is, for example, a position, a velocity, an acceleration, or an orientation. The person skilled in the art will easily find other parameters to be comprised by a state. For example, a state of an apparatus, is understood as at least one parameter for characterizing the apparatus in relation to the guiding means.

Processing at least one target state allows establishing preliminary objectives for the at least one apparatus. The configuration of these objectives depends on how the method is intended to be applied. For example, if a pattern is recognized regarding a static object left unattended in the mid- die of the road at a certain position in relation to the guiding means, then, in one embodiment, processing at least one target position would result in setting a target state with a position on the guiding means equal to the sensed position of the static object. Another embodiment, would be to process at least two target states with positions on the guiding means near the sensed position of the static object. This embodiment would allow to retrieve several sensor data feeds, from different perspectives, of the same subject.

An apparatus is selected to achieve a target state based on an estimation of the time it takes for the apparatus to achieve said target state. The method attempts to achieve those target states quickly. Furthermore, the method only focuses in achieving the target states directly, in order to avoid intersections between apparatus routes on the guiding means. Intersecting routes would result on the respective apparatuses colliding with each other.

The person skilled in the art in the art will easily implement the estimation of the time it will take for an apparatus to achieve a target state. This data is processed based on the current state of each apparatus, which can be obtained, for example, by querying each one. A solution to estimate the time it will take for an apparatus to achieve a target state is, for example, to assume mean times between locations on the guiding means. Another example is making use of assumed acceleration and deceleration coefficients of the apparatuses, for further refining the estimated time. A further example is an embodiment based on the physics' equations of motion, or any other similar model. Another example, makes use a pre-configured physical model of the tunnel, taking into account considerations such as curvature or inclination.

With the present method, the state of each apparatus is dynamically handled, in synchronicity with the physical occurrences in the tunnel. The method allows avoiding collisions between apparatuses moving on the guiding means, by focusing on capturing sensor data of a subject, irrespectively of which apparatus captures said sensor data.

In one embodiment, the processing of at least one target state for an apparatus, based on the received sensor data, comprises:

- processing a velocity of a subject, based on the received sensor data;

- estimating a future state of the subject, based on the processed velocity of the subject; and

- processing at least one target state for an apparatus, based on the estimated future state of the subject.

A subject is understood as something that is conveyed by the sensor data. In a road tunnel, a subject might be, for example, a tanker carrying explosive cargos, a vehicle transporting someone under legal surveillance, or an unwanted static object on the road. In an industrial tunnel, a subject might be, for example, a maintenance worker performing tasks on the tunnel, or a cart carrying valuable raw gemstones. A state of a subject is understood as at least one parameter for characterizing the subject in relation to the guiding means. Also, a state which characterizes a subject in relation to the tunnel is understood to also characterize said something in relation to the guiding means, since the guiding means is itself positioned along the tunnel. For example, a subject state which comprises a velocity of a subject in relation to a tarmac road inside the tunnel can easily be converted to a velocity of the subject in relation to the guiding means. The person skilled in the art will see that same conversion can be processed for other parameters, such as, for example, a position, an acceleration, or an orientation.

Processing a velocity of a subject is achieved, for example, using third-party solutions, depending on the sensor data in which said processing is based. For example, if the sensor data is a video signal, then a software solution can process the velocity of the subject while this is captured by the video. The person skilled in the art will implement the step of processing a velocity of a subject, depending on the type of sensor data received, by making use of, for example, third-party solutions.

Estimating a future state of the subject is performed based on the processed velocity of the subject. For example, with the processed velocity of the subject at a sensed position in relation to the guiding means, it is possible to estimate where the subject will be after a certain period of time, said period of time being predefined. On another example, further information is used to refine the estimation, for example by making use of the known curvature or inclination of the tunnel. On a further example, the typical sensed velocities of subjects in several positions on the tunnel, are tracked and used for the estimation of a future state of the subject. A typical sensed velocity is, for example, the mean velocity of a subject sensed a certain position in relation to the guiding means. On one example, the entries inserted on the queue, after patterns are recognized, are also used for estimating a future state of a subject. If a traffic accident is detected ahead of a subject moving towards it, then this information can be used to estimate that the subject will slow down.

Processing at least one target state for an apparatus, based on the estimated future state of a subject, allows monitoring a moving subject. For example, on a road tunnel it is possible to monitor a tanker carrying dangerous cargos while said tanker travels through the tunnel. Another example is monitoring maintenance operations on a tunnel, allowing to record all moments while the maintenance workers are in the tunnel, such as while they walk along the tunnel.

With the possibility of monitoring moving subjects, it is especially important to efficiently assign target states to the apparatuses and avoiding collisions between them on the guiding means.

In another embodiment, the selecting of at least one apparatus, with a minimum estimated time to directly achieve the at least one target state, comprises: - processing a minimum estimated time for at least one apparatus to directly achieve the at least one target state, based on at least one lookup of a previous target state to which the at least one apparatus was controlled to directly achieve.

This embodiment achieves an efficient use of the communication means by minimizing the number of exchanged messages with the apparatuses. By looking up what was the previous target state to which an apparatus was controlled to move directly to, it is possible to assume that, and make use of, this information as the current state of the apparatus. Hence, this speeds up the steps that occur after a pattern is recognized, since there is less time being expended on communicating with the apparatuses.

In a further embodiment, the queue is a priority queue, and each entry in said priority queue has a priority value equal to a pre-defined priority value of a pattern to which said entry relates to.

This embodiment effectively allocates resources along the guiding means. For example, on a road tunnel if there are only two apparatuses and they are both monitoring a maintenance operation on one end of the tunnel, and suddenly there is fire pattern being recognized on the other end of the tunnel, then at least one of the apparatuses stops monitoring the maintenance operation and moves to the pattern location.

The priority value is specific to each pattern, and, when an entry is retrieved from the priority queue, the entries relating to a pattern which should be prioritized, are the ones which are first retrieved from the priority queue. Examples of patterns and the respective priority value that can be assigned to each one are:

- an high level of traffic in a road, with a low priority value;

- an high level of air pollutants in a road tunnel, with a medium priority value;

- an unknown object detected in the middle of a road tunnel, with a high priority value; and

- a fire on a road tunnel, with a high priority value.

The person skilled in the art will see that the relative values presented for these patterns are easily implemented, for example with integers. It also be seen that different patterns can have equal priorities, and that in case of conflict the method can prioritize tasks in many ways, for example by choosing randomly, or by choosing the first of the entries with the same priority.

In one embodiment, a state comprises a position, a speed, and an orientation.

The parameters described on this embodiment, allow refining and improving the estimation of the time it takes for an apparatus to achieve a target state. With more information and details it is possible to have a more accurate estimation. For example, with this information about the current state of an apparatus, it is possible to understand that in order to achieve a target state, an apparatus might need to revert its orientation on the guiding means. On this scenario, the initial time for slowing down and reverting the orientation can also be accounted for. Another example is providing target states with a velocity different than zero, which is useful while monitoring moving subjects.

In another embodiment, the recognizing of a pattern on the received sensor data, comprises any of:

- recognizing a vehicle and analysing if said vehicle should be monitored;

- recognizing a fire;

- recognizing a smoke cloud;

- recognizing a person walking in the tunnel;

- recognizing a person asking for help;

- recognizing a mechanical defect on a vehicle or on the tunnel;

- recognizing a static object in the tunnel.

As pointed out above, the person skilled in the art will easily implement the recognition of these patterns, depending on the type of sensor data received. This is done by either implementing a solution from known available software that receives the available types of sensor data as input, or by buying a commercial product for the purpose. Each of the recognizable patterns on this embodiment can be recognized based on multiple types of sensor data. For example, a mechanical defect may be recognized both from audio sensor data, as well as from video sensor data.

In a further embodiment, the method comprises receiving a sensor data from at least one of:

- a fixed video monitoring system;

- an Intelligent Transportation System;

- an Electronic Toll Collection system; or

- a tunnel security system.

This embodiment integrates sensor data into the tunnel monitoring system from other systems. A fixed video monitoring system can, for example, be placed at the ends of the tunnel, monitoring any subject entering or leaving the tunnel. Integration to fixed entrance cameras will allow the system to continuously monitor relevant traffic and enable the identification of each vehicle in the tunnel. Electronic Toll Collection systems, such as Q-Free, can be used to monitor and identify which vehicles are inside the tunnel. Any data received from Intelligent Transportation System can be used for detecting incidents or other relevant events. A tunnel security system, for example a fixed fire detection system, can also be used as an alternative to detected incidents.

Herein is also disclosed a tunnel monitoring system, comprising:

- a server comprising a communication means;

- a guiding means positioned along a tunnel;

- at least one apparatus comprising a driving means for moving on the guiding means, at least one sensor, and a communication means for sending sensor data to the server,

where the server is configured to implement the method described above.

A server is understood as at least one computational process, which is executed on at least one physical computer, which can be connected as to form a network of machines. Said server can, for example, be executed on a control room provided for the personnel to monitor the tunnel remotely.

In one embodiment, the communication means of the at least one apparatus is a wireless communication means.

In another embodiment, the at least one apparatus comprises at least one of:

- an image sensor;

- a sound sensor;

- a gas sensor; or

- a temperature sensor.

An image sensor, allows capturing an image or video data from inside the tunnel. For example, a video sensor, such as a video camera, allows capturing a video feed. Other examples of image sensors are infrared sensors and radar sensors that allows capturing images even when there is low visibility inside the tunnel, for example when there is smoke. The person skilled in the art will easily find other image sensors suitable for being installed on an apparatus.

A sound sensor allows to capture sound related data from inside the tunnel. It can be, for example, a microphone.

A gas sensor allows to capture data about gases inside the tunnel. For example, an air pollutant sensor for air pollutants such as ozone, carbon monoxide or nitrogen oxides.

In a further embodiment, the at least one apparatus comprises at least one of:

- a light emitter;

- a sound emitter.

These emitters allow to further actuate on the environment inside the tunnel. For example, the sound emitter allows to send warnings or any other kind of audio signals to the tunnel. Another example is the light emitter, that allows to send visual signals to the inside of the tunnel. These signals can be indicative lights, such as a traffic light, or projections, for example on the ground.

The possibility of emitting light from an apparatus, in connection to the possibility of monitoring moving subjects, allows achieving an embodiment of a moving traffic light. For example, when a dangerous moving subject enters a tunnel, such as a gas truck, and it is desirable in many cases to project a red signal on the floor behind said subject. In this way, while the subject moves along the tunnel, other traffic is signalled to maintain a certain security distance from the dangerous subject. Another embodiment projects signals including text, on the tunnel wall or floor of the tunnel, achieving a moving traffic sign. The person skilled in the art will easily find other embodiments where the light emitter and/or the sound emitter are controlled based on the received sensor data.

In one embodiment, the guiding means is positioned at a higher elevation than the floor of the tunnel.

The person skilled in the art will easily foresee many alternatives implementations of this aspect of the solution. In another embodiment, the guiding means is a rail. For example, a rail suspended from ceiling or walls.

In a further embodiment, the communication means of the server is configured with at least one connection to any of:

- a fixed video monitoring system;

- an Intelligent Transportation System;

- an Electronic Toll Collection system; or

- a tunnel security system,

for receiving sensor data.

Brief description of the drawings

Examples of preferred embodiments are herein described, which are also illustrated in the accompanying drawings.

Fig. 1 illustrates an embodiment of the tunnel monitoring system comprising a guiding means implemented as a single rail fixed to the ceiling of the tunnel;

Fig. 2 illustrates an embodiment of the tunnel monitoring system comprising a guiding means implemented as a double rail fixed on each side of the tunnel;

Fig. 3 illustrates a section view of an embodiment of an apparatus and its connection to the guiding means;

Fig. 4 illustrates an embodiment of an apparatus comprising driving means for being suspended from the guiding means;

Fig. 5 illustrates an embodiment of an apparatus;

Fig. 6 illustrates a flow of the assignments of the target states on an embodiment of the method with moving subjects;

Fig. 7 illustrates an embodiment of the tunnel monitoring system comprising a fixed video monitoring system on the entrance of the tunnel;

Fig. 8 illustrates an embodiment of the method where a moving traffic light is implemented; Fig. 9 illustrates an application of the tunnel monitoring system on an emergency situation; and

Fig. 10 illustrates an embodiment of the step of processing at least one target state for an apparatus, based on an estimated future state of the subject.

Detailed description

Figures 1 and 2 show a section view of a tunnel 3 comprising two possible embodiments of the guiding means. Figure 1 implements an apparatus 1 suspended from a single rail fixed to the centre of the ceiling of the tunnel 3 and figure 2 implements a double rail fixed on each side of the tunnel 3.

Figure 3 shows an apparatus 1 suspended from a guiding means 2, in this case a rail, attached to an inclined wall of the tunnel 3.

Figures 4 and 5 further show detailed embodiments of an apparatus 1 , applicable on the previous embodiments where the apparatus is suspended on the guiding means 2. On figures 4 and 5, the driving means 4 are observable on the upper part of the apparatus 1.

Figure 6 shows a flow of the assignments of the target states on an embodiment of the method with moving subjects. Considering the vehicles shown are initially being monitored by the two apparatuses 1 , when the vehicles start to cross each other while moving on opposing directions, the subjects which are being monitored are swapped between the apparatuses. This occurs due to an update of the target states the apparatuses receive.

On this embodiment a security distance between apparatuses is configured, in order to avoid collisions between them.

Figure 7 illustrates an embodiment of the tunnel 3 monitoring system comprising a fixed video monitoring system 5 on the entrance of the tunnel. After the vehicle enters the tunnel 3, it gets recognized by the fixed video monitoring system 5. From the sensor data received from this system, a pattern is recognized, and the tunnel monitoring will now monitor the entire path of the vehicle through the tunnel with apparatus 1.

Figure 8 illustrates an embodiment of the method where a moving traffic light is implemented. The apparatus 1 keeps moving at a fixed distance of the gas tanker illustrated, while at the same time projecting a red line on the road. A second vehicle is shown on the figure, using that projected line as means of keeping a safe distance from the dangerous vehicle.

Figure 9 illustrates a further embodiment where an infrared video feed received from an apparatus 1 is forwarded to an emergency assistance vehicle, in this case a fire truck. Although the fire truck conductor cannot see through the smoke inside the tunnel, he can however see on the received infrared video feed what is happening in the tunnel besides the smoke. This allows him to identify a person running towards the fire truck in the middle of the smoke.

Figure 10 illustrates an embodiment of the step of processing at least one target state for an apparatus, based on an estimated future state of the subject. The top part of the figure illustrates an exemplary scenario observable in a tunnel 3. Three vehicles are shown, A, B, and C, moving in one direction, from the right to the left. After receiving sensor data, a computer representation 101 is generated based on said sensor data, which comprises the step of processing a velocity of each vehicle. A simulation 102 then occurs, where the step of estimating a future state of a vehicle is performed. In this embodiment, the final result provides an estimate of where the three vehicles will be after 130 seconds. Vehicle A, not shown in the lower part of the figure, is estimated to be out of the tunnel after 130 seconds.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware.