GB2582901A

GB2582901A - A control system for a vehicle and a method

Info

Publication number: GB2582901A
Application number: GB1903726.6A
Authority: GB
Inventors: Charles Lewin Andrew; Cenciotti Luca; Slater Stephen
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2019-03-19
Filing date: 2019-03-19
Publication date: 2020-10-14
Anticipated expiration: 2039-03-19
Also published as: GB201903726D0; GB2582901B

Abstract

A control system configured to receive first and second sensor signals 801, 802 from two different types of sensing means, determine a malfunction 807 of the first sensing means based on the second sensor signal being indicative of an object being detected and the first sensor signal not being indicative of the object being detected 806, and provide an output signal in dependence on the determined malfunction 807. A third sensing means could be included. Types of sensing means could include radar, cameras, or lidar. The output means may be provided to a human-machine interface, for providing an alert, or provided to a diagnostic interface. Autonomous braking may be initiated based on the first and second sensor signal indicating an object’s presence, or based on the second sensor signal, regardless of the first sensor signal. The range of angles the first sensing means covers could be adjusted. A magnitude of reduction in sensitivity could be output based on the first and second sensor signals. A malfunction could be based on repeated occurrences of an object not being detected.

Description

A CONTROL SYSTEM FOR A VEHICLE AND A METHOD

TECHNICAL FIELD

The present disclosure relates to a control system for a vehicle and a method. In particular, but not exclusively it relates to a control system for a vehicle and a method of monitoring a status of sensing means in a vehicle such as a road vehicle.

Aspects of the invention relate to a control system for a vehicle, vehicle, a method and a non-transitory computer readable medium.

BACKGROUND

Sensing devices, such as radar, are becoming increasingly common in modern vehicles for automated drive and active safety applications. Both corner radars ("short range" or SRR) and front radars (mid-range or long range MRR/LRR) are being integrated behind plastic panels which are nominally transparent to radio frequencies used by the radar. In practice, metallic paint and badges etc. often inhibit the actual performance achieved. Even worse, overpainting, water ingress between layers of badges, or collision damage induced misalignment can further degrade range performance. Corner radars in particular are ideally mounted on a solid structure such as Body-in-White (BiW) or Bumper Support Bracket (BSB) just underneath the outer skin of the bumper. This is usually perfectly practical for the rear of the vehicle where the appropriate structures are normally available and there is space to incorporate the required bracketry or modify the BSB. With new front corner radar based capabilities being required to support the European New Car Assessment Programme (Euro NCAP) features such as Junction Autonomous Emergency Braking (JAEB) from 2020, the challenge extends to the front packaging. Here there are often less options available, mainly due to crumple zone, headlamps and the general lack of solid structures right at the front of the vehicle. In this scenario, the third choice of mounting options has to be considered, namely on the bumper B-surface (inner skin). This is less stable and also prone to deflections or distortions due to aerodynamic forces or thermal effects. Given that the vertical field of view of automotive radars is typically only --v/-6 degrees, any misalignment or instability of the mounting of these devices can have an adverse effect on their ability to perform as required.

A further problem arises with the arrival of a new interpretation of the US legislation known as the pendulum test, or NHTSA regulation 581. This was originally intended to ensure that the protective properties of bumpers would be retained even after a low speed collision, i.e. elasticity or rubber bumpers. In 2016, this legislation was re-interpreted to include sensors supporting safety features such as AEB (Autonomous Emergency Braking). This has brought significant new attention onto the ability of a corner radar which feeds AEB capability to detect damage or misalignment.

Misalignment or signal attenuation through damage, overpainting etc. will typically degrade the range capability of the radar which could render the active safety or autonomous drive capabilities of the vehicle less effective. Analysis of the radar signal qualities alone will not allow suitable diagnostics, as it is difficult to distinguish between damage induced range degradation and changes in traffic characteristics, e.g. empty roads etc. Other sensing devices, that may be used for automated drive and active safety systems, may be similarly susceptible to degradation in performance caused by misalignment and/or reduced sensitivity. For example, the performance of a camera or a lidar (light detection and ranging) device may be degraded due to contamination of a window through which light is received by the sensing device. If the degraded performance goes undiagnosed, then the system could become less effective It is an aim of the present invention to address one or more of the disadvantages associated with the prior art.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a control system for a vehicle, a vehicle, a method and a non-transitory computer readable medium as claimed in the appended claims.

According to an aspect of the invention there is provided a control system for a vehicle, the control system comprising one or more controllers, the control system configured to: receive a first sensor signal from a first sensing means of a vehicle, the first sensing means being of a first type; receive a second sensor signal from a second sensing means of the vehicle, the second sensing means being of a second type; determine a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected; and provide an output signal in dependence on the determined malfunction.

This provides the advantage that a malfunction of a sensing means that could cause a reduction in effectiveness of a control system is diagnosed, so that an appropriate alert may be provided and/or an appropriate action may be performed in view of the reduced performance of the malfunctioning sensing means. For example, an advanced driver-assistance system (ADAS) that makes use of the signals from the malfunctioning sensing means may determine to perform a function in dependence on signals provided by other sensing means, without relying on the malfunctioning sensing means, or alternatively the ADAS may prevent that function being provided to the driver.

Optionally, the control system is configured to determine a distance to the object in dependence on the second sensor signal and determine the malfunction in dependence on said distance and an expected capability of the first sensing means. This provides the advantage that when the first sensing means becomes incapable of positively detecting objects at a distance where positive detection is expected, the control system is able to determine that the first sensing means has malfunctioned based on the signal from a sensing means of a different type.

Optionally, the first type comprises one of: a radar device; a camera; and a lidar device.

Optionally, the first type and the second type each comprise a different one of: a radar device; a camera; and a lidar device.

Optionally, the control system is configured to: provide the output signal to a human-machine interface for providing an alert to a user of the vehicle; and/or provide the output signal to a diagnostic interface of the vehicle for providing information of the vehicle. This provides the advantage that the user and/or a person performing a service of the vehicle are able to take appropriate action.

Optionally, before the determination of the malfunction, the control system is configured to cause autonomous emergency braking in dependence on the first sensor signal indicating the presence of an object and the second sensor signal indicating the presence of the same object.

Optionally, in dependence on the determined malfunction of the first sensing means, the control system is configured to cause autonomous emergency braking in dependence on a received sensor signal from the second sensing means, regardless of the first sensing means. This provides the advantage that autonomous emergency braking may still be performed in instances where it would not be performed if the control system awaited appropriate signals from the first sensing means.

Optionally, before the determination of the malfunction, the control system is configured to cause autonomous emergency braking in dependence on the presence of an object being indicated by the first sensor signal, the second sensor signal and a third sensor signal received from a third sensing means; and in dependence on the determined malfunction of the first sensing means, the control system is configured to cause autonomous emergency braking in dependence on received sensor signals from the second sensing means and the third sensing means, regardless of the first sensing means. This provides the advantage that autonomous emergency braking may still be performed in instances where it would not be performed if the control system awaited appropriate signals from the first sensing means.

Optionally, the third sensing means comprises one of: a radar device; a camera; and a lidar device.

Optionally, the control system is configured to provide the output signal to the first sensing means to cause said first sensing means to adjust a range of angles over which it is capable of positively detecting objects. This provides the advantage that, in instances where the malfunction is caused by misalignment, the performance of the first sensing means may be improved.

Optionally, the control system is configured to determine a magnitude of reduction in sensitivity of the first sensing means in dependence on sensor signals received from the first sensing means and from the second sensing means; and the output signal is indicative of the magnitude of reduction in sensitivity. This provides the advantage that a system relying on the first sensor signal is able to decide whether to, or how to, use the first sensing means based on the degree by which the sensitivity has reduced. For example, if the sensitivity is greatly reduced it may be most appropriate to discontinue an ADAS function and alert the driver. Alternatively, if the sensitivity is reduced by a lesser amount, it may be appropriate to continue to provide the ADAS function, but provide an indication of the malfunction via a diagnostic interface.

Optionally the malfunction of the first sensing means is determined in dependence on repeated occurrences of the second sensor signal being indicative of an object being positively detected when the first sensor signal is not indicative of the object being positively detected.

According to another aspect of the invention there is provided a vehicle comprising the first sensing means, the second sensing means and the control system of any one of the previous paragraphs.

According to a further aspect of the invention there is provided a method of monitoring status of a vehicle, the method comprising: receiving a first sensor signal from a first sensing means of a vehicle, the first sensing means being of a first type; receiving a second sensor signal from a second sensing means of the vehicle, the second sensing means being of a second type; determining a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected; and providing an output signal in dependence on said determining a malfunction.

This provides the advantage that a malfunction of a sensing means that could cause a reduction in effectiveness of advanced driver-assistance system (ADAS) is diagnosed, so that an appropriate alert may be provided and/or an appropriate action may be performed in view of the reduced performance of the malfunctioning sensing means. For example, the advanced driver-assistance system (ADAS) that makes use of the signals from the malfunctioning sensing means may determine to perform a function in dependence on signals provided by other sensing means, without relying on the malfunctioning sensing means, or alternatively the ADAS may prevent that function being provided to the driver.

Optionally, the method comprises determining a distance to the object in dependence on the second sensor signal and determining the malfunction in dependence on said distance and an expected capability of the first sensing means. This provides the advantage that when the first sensing means becomes incapable of positively detecting objects at a distance where positive detection is expected, a malfunction of the first sensing means may be determined based on the signal from a sensing means of a different type.

Optionally, the method comprises: providing the output signal to a human-machine interface for providing an alert to a user of the vehicle; and/or providing the output signal to a diagnostic interface of the vehicle for providing information during servicing of the vehicle. This provides the advantage that the user and/or a person performing a service of the vehicle are able to take appropriate action.

Optionally, before the determination of a malfunction, the method comprises providing an autonomous emergency braking in dependence on the first sensor signal indicating the presence of an object and the second sensor signal indicating the presence of the same object.

Optionally, after the determined malfunction of the first sensing means, the method comprises providing autonomous emergency braking in dependence on a received sensor signal from the second sensing means, regardless of the first sensing means. This provides the advantage that autonomous emergency braking may still be performed in instances where it would not be performed if appropriate signals from the first sensing means were awaited.

Optionally, before the determination of a malfunction, the method comprises causing autonomous emergency braking in dependence on the presence of an object being indicated by the first sensor signal, the second sensor signal and a third sensor signal received from a third sensing means; and after the determined malfunction of the first sensing means, the method comprises causing autonomous emergency braking in dependence on received sensor signals from the second sensing means and the third sensing means, regardless of the first sensing means. This provides the advantage that autonomous emergency braking may still be performed in instances where it would not be performed if appropriate signals from the first sensing means were awaited.

Optionally, the method comprises providing the output signal to the first sensing means to cause said first sensing means to adjust a range of angles over which it is capable of detecting objects. This provides the advantage that, in instances where the malfunction is caused by misalignment, the performance of the first sensing means may be improved.

Optionally, the method comprises determining a magnitude of reduction in sensitivity of the first sensing means in dependence on sensor signals received from the first sensing means and from the second sensing means; and the output signal is indicative of the magnitude of reduction in sensitivity. This provides the advantage that a system relying on the first sensor signal is able to decide whether to, or how to, use the first sensing means based on the degree by which the sensitivity has reduced. For example, if the sensitivity is greatly reduced it may be most appropriate to discontinue an ADAS function and to alert the driver. Alternatively, if the sensitivity is reduced by a lesser amount, it may be appropriate to continue to provide the ADAS function, but provide an indication of the malfunction via a diagnostic interface.

According to yet another aspect of the invention there is provided a non-transitory computer readable medium comprising computer readable instructions that, when executed by a processor, cause performance of a method according to any one of the previous paragraphs.

According to yet a further aspect of the invention there is provided at least one controller comprising at least one electronic processor having an electrical input for receiving the first signal and the second signal and at least one electronic memory device electrically coupled to the electronic processor and having instructions stored therein, wherein the processor is configured to access the memory device and execute the instructions stored therein such that it is operable to perform the method of any one the previous paragraphs.

According to yet another aspect of the invention there is provided a control system for a vehicle, the control system comprising one or more controllers, the control system being configured to: receive at least one first sensor signal from a first sensing means of a vehicle; receive at least one second sensor signal from a second sensing means of a vehicle; determine a magnitude of reduction in sensitivity of the first sensing means in dependence on the at least one second sensor signal being indicative of an object being positively detected and the at least one first sensor signal not being indicative of the object being positively detected; and provide an output signal indicative of the magnitude of reduction in sensitivity. This provides the advantage that a system relying on the first sensor signal is able to decide whether to, or how to, use the first sensing means based on the degree by which the sensitivity has reduced. For example, if the sensitivity is greatly reduced it may be most appropriate to discontinue an ADAS function and alert the driver. Alternatively, if the sensitivity is reduced by a lesser amount, it may be appropriate to continue to provide the ADAS function, but provide an indication of the malfunction via a diagnostic interface.

According to a yet further aspect of the invention there is provided a control system for a vehicle, the control system comprising one or more controllers, the control system being configured to: provide a driver-assistance function by providing output signals to control speed of a vehicle, in dependence on signals received from a first sensing means of the vehicle and a second sensing means of the vehicle; receive a first sensor signal from the first sensing means; receive a second sensor signal from the second sensing means; determine a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected; and provide the driver assistance function in dependence on signals received from the second sensing means, regardless of signals received from the first sensing means, in dependence on the malfunction being determined.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 shows a first vehicle comprising a control system embodying the present invention; Fig. 2 shows the first vehicle on a road behind a second vehicle, with the sensing means of the first vehicle all operating with their expected capabilities; Fig. 3 shows the first vehicle on a road behind the second vehicle, with its radar device redirected to an orientation a few degrees upwards from its correct orientation; Fig. 4 shows the scenario of Fig. 3 but at a subsequent time when the distance between the first vehicle and the second vehicle has reduced; Fig. 5 shows the first vehicle on a road behind the second vehicle, with its radar device correctly orientated but the radar's sensitivity reduced; Fig. 6 shows schematically the control system of Fig. 1; Fig. 7 shows a flowchart illustrating a method of monitoring the status of sensing means of a vehicle; Fig. 8 shows a flowchart illustrating a method, which provides a more specific example of the method of Fig. 7; Fig. 9 shows a flowchart illustrating a method, which provides a more specific example of the method of Fig. 8; and Fig. 10 shows a flowchart providing an example of the processes that may be performed within the method of Fig. 8 or Fig. 9 in respect of each driver assistance function of an ADAS system.

DETAILED DESCRIPTION

A control system 101 for a vehicle 100, a vehicle 100, a method 700 and a non-transitory computer readable medium 601 in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figures 1 to 10.

With reference to Figure 1, the vehicle 100 is a road vehicle, which in the present embodiment is a car having four road wheels 102, that are driven by a powertrain (not shown) in accordance with signals provided by a powertrain control module 103 of the vehicle 100. The vehicle 100 also comprises a braking system 104 for controlling braking of the vehicle 100.

The vehicle 100 further comprises a control system 101, which in the present embodiment, is an advanced driver assistance system (ADAS) arranged to provide control signals to the powertrain control module 103 and/or to the braking system 104 to control (when required) the speed of the vehicle 100 in dependence on signals received from several different types of sensing means 105 configured to sense objects in the vicinity of the vehicle 100.

In the present embodiment, the sensing means 105 comprises three different types of sensing device, namely a radar device 106, a lidar (light detection and ranging) device 107 and a stereo camera 108.

The space within which a sensing means 105 is capable of positively detecting an object is referred to herein as a "field of detection". The phrase "positively detecting", "positively detected", "positive detection", or similar phrases, refer herein to sensing that indicates a sufficiently high confidence level that an object has been detected. For example, in the case of a radar device 106, a positive detection may be dependent on the magnitude of a signal caused by a sensed object being sufficiently large compared to the current signal to noise ratio.

The sensing means 105 are arranged so that when they are operating correctly they have overlapping fields of detection. Consequently, the position and velocity of an object may be detected by more than one of the sensing means 105, and the data generated by those sensing means may be combined in a sensor fusion process by the control system 101 to improve the accuracy and certainty with which objects are detected.

As will be described in further detail below, the control system 101 is configured to analyse signals generated by the sensing means 105 to determine when one of the sensing means is not operating with its expected capability.

The vehicle 100 further comprises a human-machine interface 109, such as a display screen, that is configured to provide information to a user of the vehicle 100. In the present embodiment, in dependence on one of the sensing means 105 not operating within specified criteria, the control system 101 is arranged to provide output signals to the human-machine interface 109 to cause it to provide an alert to the user.

The vehicle 100 may also comprise a diagnostic interface 110 to enable the control system 101 to provide a signal indicative of the capabilities of the sensing means 105 for use when servicing the vehicle 100. Consequently, the control system 101 is able to provide information indicative of reductions in sensitivity of a sensing means 105 and/or provide information indicative of a malfunction of one of the sensing means 105 in dependence on that sensing means 105 not operating within specified criteria. The diagnostic interface 110 may be configured to provide wired or wireless communication.

In alternative embodiments, the control system 101 may be arranged to receive signals from just two different types of sensing means 105, such as a radar device 106 and a camera 108, or a radar device 106 and a lidar device 107, or a lidar device 107 and a camera 108, and determine a malfunction of a sensing means of one type in dependence on signals received from the sensing means of the other type. In other alternative embodiments, the control system 101 may be arranged to receive signals from more than three different types of sensing means 105.

The word "type' as used herein in respect of sensors or sensing means refers to a category of sensor that is sensitive to a specified range of radiation and operates in accordance with a specified method. For example, in the present embodiment, the radar device 106 transmits electromagnetic radiation in the form of radio waves and senses reflected radio waves, whereas the lidar device 107 and camera 108 are both sensitive to light or near infrared.

Also the lidar device 107 operates in a different manner to the camera 108 in that it transmits laser light and senses reflected transmitted light, whereas the camera 108 senses ambient light over a relatively wide range of wavelengths.

In the present example, the radar device 106 is positioned centrally at the front of the vehicle 100, behind a part of its bodywork 111 that defines its front bumper. In alternative embodiments, the single radar device 106 may be replaced by a radar system comprising two radar devices 106A that are also located at the front of the vehicle 100 but at opposite sides of the vehicle 100. i.e. they are positioned at the front corners of the vehicle 100. The fields of detection of the radar devices 106A have sufficiently wide angles to enable the radar devices 106A to detect objects ahead of the vehicle 100 as well as to the sides of the vehicle 100. Typically the fields of detection of the radar devices 106A overlap in front of the vehicle 100 by about 10 degrees. In this embodiment, each of the radar devices 106A are required to detect objects directly ahead of the vehicle 100 and also objects, such as vehicles or people, that approach the path of the vehicle 100 from their respective sides.

In further alternative embodiments, the vehicle 100 has both the centrally positioned radar device 106 and two additional radar devices 106A at the front corners of the vehicle 100, which are configured to only detect objects that approach the path of the vehicle 100 from their respective sides.

An example of the operation of the control system 101 is illustrated by Figs. 2, 3, 4 and 5. As will be described below, the control system 101 is configured to compare signals received from each of the sensing means 105 to determine whether each of the different types of sensing means 105 is operating with its expected capability.

For the avoidance of confusion, the vehicle 100 is referred to below as the first vehicle 100. In each of these figures, the first vehicle 100 is shown on a road 201 behind a second vehicle 200.

The angles within which a sensing means 105 is able to detect an object depends on its design. Also, for each of the different sensing means 105, the ranges within which they are able to positively detect an object depends on properties of the object, such as its size. However, a space within which each sensing means 105 is capable of positively detecting a typical sized vehicle, such as vehicle 200, is illustrated for each of the sensing means 105.

The field of detection of the lidar device 107 is shown in small dashed outline 202, the field of detection of the radar device 106 is shown in large dashed outline 203 and the field of detection of the camera 108 is shown in dotted outline 204. Although the field of detection of each sensing means 105 is different to that of the other sensing means 105, it overlaps the

field of detection of the other sensing means 105.

In Fig. 2 the sensing means 105 are all operating with their expected capabilities. They are correctly oriented and operating with sensitivities within defined specifications. Although there is some variation in the range capabilities of the various types of sensing means 105, the second vehicle 200 is within the field of detection 202, 203 and 204 of each sensing means 105. Consequently, the control system 101 is able to perform a process of sensor fusion based on the signals received from the sensing means 105 and determine an accurate position and velocity of the second vehicle 200 relative to the first vehicle 100. It is also able to compare signals received from each of the sensing means 105 to confirm that each of the different types of sensing means 105 is operating with its expected capability.

In the example of Fig. 3, the first vehicle 100 has recently been in a minor accident in which the radar device 106 has been moved a few degrees about a horizontal axis from its correct orientation. Consequently, the field of detection 203 of the radar device 106 has been redirected to an orientation a few degrees upwards from its correct orientation, so that the radar device 106 is unable to detect the presence of the second vehicle 200 at its current distance from the first vehicle 100. The second vehicle 200 is within the field of detection of both the lidar 107 and the camera 108, which are able to provide signals to the control system 101 indicative of the presence and position of the vehicle 200. The control system 101 is therefore able to determine from these signals the position of the second vehicle 200, and, by comparing this information to the expected capabilities of the radar device 106, it is able to determine that the radar device 106 is not operating correctly.

The scenario of Fig. 3 is shown again Fig. 4 at a subsequent time when the distance between the first vehicle 100 and the second vehicle 200 has reduced but the second vehicle 200 is still outside of the field of detection of the radar device 106. The lidar 107 and the camera 108 have continued to provide data to the control system 101 indicative of the distance of the second vehicle 200 from the first vehicle 100 as the distance decreased, and consequently the control system 101 has been able to determine an indication of the magnitude of the reduction in the range of the radar device 106.

The control system 101 may be configured to cause the human-machine interface 109 to provide an alert to the user of the first vehicle 100 in dependence on the magnitude of the reduction in range of the radar device 106 being below a specified range. The control system 101 may also indicate to the user that one or more ADAS functions are no longer operational, due to the lack of information from the radar device 106 and the resulting reduction in confidence of the control system 101 to obtain accurate measurements of objects such as the vehicle 200.

In addition, or alternatively, the control system 101 may be configured to provide an output signal to the diagnostic interface 110 of the vehicle 100 to enable the reduction in range to be investigated during a service of the vehicle 100.

In addition, or alternatively, the control system 101 may be configured to enable ADAS functions to be performed regardless of signals, or lack of signals, from one of the sensing means 105 that is malfunctioning. For example, if the control system 101 determines that the reduction in range of the radar device 106 has fallen below a predefined threshold distance, it may continue to provide a cruise control function based on measurements made by the lidar device 107 and camera 108, without regard to the signals received from the radar device 106. Or alternatively, the control system 101 may make use of the signals from the malfunctioning sensing means 105 only when the other sensing means 105 indicate that a detected object is within the reduced range of the malfunctioning sensing means 105.

In some embodiments, one or more of the sensing means 105 may be provided with a means of adjustment of the vertical range of angles over which they are able to detect objects. For example, the lidar device 107 may be designed to enable its laser to scan up to 25 degrees in the vertical direction, but during normal use in the vehicle 100, the lidar device 107 may be configured to scan only over the central 15 degrees of the 25 degrees.

However, if the orientation of the lidar device 107 is inadvertently altered so that its field of detection relative to the vehicle 100 is too high or too low, for example by damage to the vehicle 100, the control system 100 may be arranged to provide an output signal to the lidar device 107 to cause it to adjust the vertical range of angles over which it scans, so that the orientation of it field of detection is corrected.

In Fig. 5, the radar device 106 is correctly orientated but its sensitivity, and therefore its range, has been substantially reduced. This may be the result of material being added to the vehicle 100 in the path of the radar device 106. For example, the body of the vehicle 100 in front of the radar device 106 may have been painted, it may have had a badge applied to it, and/or it may be covered with dirt. Like in the examples of Figs. 3 and 4, by comparing signals received from the radar device 106 and the other sensors 107 and 108, the control system 101 determines that the radar device 106 is not positively detecting a second vehicle 200 that is within its expected range. Consequently the control system 101 determines a magnitude of the reduction in sensitivity in dependence on the signals received from the lidar device 107 and the camera 108 being indicative of the detected object (i.e. second vehicle 200) and the signal from the radar device 106 not being indicative of the object being positively detected.

The examples of Fig. 3, 4 and 5 illustrate scenarios in which the radar device 106 is malfunctioning, and the malfunction is determined based on signals from the lidar device 107 and the camera 108, which indicate the presence of an object that the radar device 106 is failing to detect. However, it will be appreciated that in other similar examples, a malfunction of the lidar device 107 may be determined based on signals from the radar device 106 and/or the camera 108 which indicate the presence of an object that the lidar device 107 is failing to positively detect and which it should detect based on its expected capabilities.

Similarly, a malfunction of the camera 108 may be determined based signals from the radar device 106 and/or the lidar device 107 which indicate the presence of an object that the camera 108 is failing to positively detect and which it should detect based on its expected capabilities.

It should also be appreciated that, in an embodiment comprising the radar devices 106A (shown in Fig. 1) positioned in the front corners of the vehicle 100, malfunctions of one of the radar devices 106A may be determined by the control system 101, for example, in dependence on the camera 108 providing outputs signals indicative of an object which that radar device 106A is failing to positively detect and which it should detect based on its expected capabilities.

The control system 101 is shown schematically in Fig. 6. In the present embodiment, the control system comprises a single controller 600, but in alternative embodiments the control system may comprise sever different controller. The controller 600 comprises at least one memory device 601 for storing instructions 602, and it also comprises at least one processor 603 configured to access the instructions 602 stored in the at least one memory device 601. When executed by the processor 603, the instructions 602 are configured to cause the processor 603 to determine a malfunction of a first sensing means in dependence on a signal from a second sensing means being indicative of an object being positively detected and a sensor signal from the first sensing means not being indicative of the object being positively detected.

The control system 101 also comprises an input/output means 604 configured to enable the control system 101 to receive signals from the sensing means 105 and to provide an output signal to another component such as the human-machine interface 109 and/or the diagnostic interface 110 to provide an indication of a malfunction of one of the sensing means 105, and/or the powertrain control module 103 and/or the brake system 104 for controlling the speed of the vehicle 100. In the present embodiment, the input/output means 604 comprises a transceiver for providing data over a CAN (Controller Area Network) bus but in other embodiments the data may be communicated via a local area network (LAN) such as 100Mbps Ethernet.

A flowchart illustrating a method 700, performable by the control system 101, of monitoring status of sensing means of a vehicle 100 is shown in Fig. 7. At block 701, the method 700 comprises receiving a first sensor signal from a first sensing means 105 of the vehicle 100, the first sensing means being of a first type. At block 702, the method 700 comprises receiving a second sensor signal from a second sensing means 105 of the vehicle 100, the second sensing means being of a second type. For example, as illustrated in the example of Fig. 3, when performing the method 700 the control system 101 may receive a first sensor signal from the radar device 106, and receive a second sensor signal from the camera 108.

At block 703, the method 700 comprises determining a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected, and, at block 704, the method comprises providing a signal in dependence on the malfunction determined at block 703. Thus, for example, when performing the method 700, the control system 101 may provide an output signal at block 704 to cause the human-machine interface 109 and/or the diagnostic interface 110 to provide an indication that the radar device 106 has malfunctioned based on the signal from the camera 108 being indicative of a detected object that the radar device 106 has failed to detect.

A flowchart illustrating a method 800, which provides a more specific example of the method 3o 700, is shown in Fig. 8. At block 801, the method 800 comprises receiving a first sensor signal from a first sensing means 105 of the vehicle 100, the first sensing means being of a first type. At block 802, the method 800 comprises receiving a second sensor signal from a second sensing means 105 of the vehicle 100. the second sensing means being of a second type. Blocks 801 and 802 are therefore like blocks 701 and 702 of method 700 described above.

Optionally at block 803 the method 800 comprises receiving a third sensor signal from a third sensing means 105 of the vehicle 100. Thus, as described with reference to Fig. 1, the method 800 may comprise receiving sensor signals from three sensors such as a radar device 106, a lidar device 107 and a camera 108.

At block 804, the method 800 comprises determining a position of detected object(s) in dependence on the sensor signals received at blocks 801, 802 and (possibly) 803. None, one, or more than one object may be indicated by the received sensor signals, and a distance to each indicated object is determined at block 804.

At block 805, the method 800 comprises determining whether all positively detected objects are indicated by all sensor signals. i.e. the method 800 checks that none of the sensing means 105 has failed to positively detect an object that the other sensing means 105 have detected. If no objects are indicated by any received sensor signals then this also enables the question at block 805 to be answered in the affirmative.

If it is determined that all positively detected objects are indicated by all sensor signals, one or more ADAS functions are performed at block 808 in dependence on received sensor signals before the processes at blocks 801 to 805 are repeated, so that objects may continue to be detected and tracked.

If it is determined at block 805 that not all sensed objects are indicated by all sensor signals as being positively detected, then the process at block 806 of the method 800 is performed.

At block 806, it is determined whether an object that is not positively detected by one of the sensing means 105 is at a position where it should be positively detected if that sensing means 105 were performing with its expected capability. I.e. it is determined whether an object detected by one of the sensing means 105 is at a position where another one of the sensing means 105 should be able to detect the object with a required level of confidence.

For example, the sensing means 105 in question may be expected to positively detect objects such as the second vehicle 200 within a specified range of distances and angles, and at block 806 it is determined whether the object is within the specified range. If it is determined at block 806 that the object is at a position where it may not be expected to be detected by the sensing means 105 in question, then one or more ADAS functions may be performed at block 808 in dependence on received sensor signals before the processes at blocks 801 to 805 are repeated.

However, if it is determined at block 806 that, given the position of the object, the sensing means in question should have been able to detect the object, then a signal is provided at block 807 to indicate a malfunction of that sensing means 105.

For example, the radar device 106 may be capable of positively detecting a car at a distance of up to 200 metres, but the camera 108 may only be expected to positively detect the car at a distance of up to 150 metres. Therefore it would be expected that a car at a distance of between 150 and 200 metres would be positively detected by the radar device 106 but not by the camera 108, and the lack of indication of the car by the camera would not indicate a malfunction of the camera 108. However, if the radar device 106 indicated that the car were at a distance of say 120 metres and within the field of view of the camera 108, then the camera would not be operating within its expected capabilities and a malfunction of the camera would be indicated.

Following the process at block 807, one or more ADAS functions may be performed at block 808 in dependence on received sensor signals. The method 800 may then be repeated to continue monitoring the sensor signals to determine the presence of objects, to track detected objects and continue to provide driver assistance functions.

In some embodiments, the method 800 comprises an additional process at block 806A following the process at block 806. At block 806A, it is determined whether statistical analysis confirms that a sensing means 105 is malfunctioning. For example, the method 800 may include keeping a log of the results of the determinations performed at blocks 805 and 806, and at block 806A the statistical analysis may be performed to determine whether the most recent determinations confirm that a sensing means is malfunctioning. For example, a malfunction of a first sensing means may be confirmed at block 806A in dependence on repeated occurrences of a sensor signal of second sensing means being indicative of an object being positively detected and the sensor signal of the first sensing means not being indicative of the object being positively detected.

In embodiments comprising the process at block 806A, the process at block 807 may only be performed when the statistical analysis at block 806A confirms that a sensing means 105 is malfunctioning.

In some embodiments the expected capabilities considered at block 806 may be predetermined and fixed. However, in some embodiments, the expected capabilities of a sensing means 105 may be temporarily adjusted in dependence on that sensing means and another sensing means both having a degraded performance caused by environmental conditions. For example, degradation in visibility, caused by rain or fog, may reduce the detection range of the camera 108 and the lidar 107, and therefore the expected capabilities of the camera and the lidar could be temporarily reduced. Thus, for example, the temporary degraded performance would not need to be logged for later reporting via the diagnostic interface 110.

A flowchart illustrating a method 900, which provides a more specific example of the method 800, is shown in Fig. 9. The method 900 comprises the same processes at blocks 801 to 806 as described above with reference to Fig. 8. However, on occasions when it is determined at block 806 that the object which is not positively detected by one of the sensing means 105 is at a position where it should be positively detected if that sensing means 105 were performing with its expected capability, then the process at block 901 is performed. At block 901 it is determined whether the current distance to the object is less than a previously recorded distance to an object that was undetected by the malfunctioning sensing means 105. If it is, then the current distance is recorded at block 902.

At block 807 the signal that is provided is indicative of a magnitude of reduction in sensitivity of the malfunctioning sensing means. For example, if signals received from the camera 108 indicated gradually reducing distance to the second vehicle 200 while the radar device 106 continued to fail to provide an indication of the presence of the second vehicle 200, then at block 902 the distances to the second vehicle 200 as measured by the camera 108 may be recorded in respect of the malfunctioning radar device 106. Therefore at block 807 the signal may indicate a minimum distance at which the radar device 106 has failed to positively detect a vehicle.

As described above, the signal provided at block 807 may be output to a human-machine interface 109 and/or a diagnostic interface 110. In the event of a relatively minor reduction in sensitivity of the sensing means 105, the control system 101 may only provide the output signal to the diagnostic interface 110 so that the malfunction may be investigated at a later date. Alternatively, if the reduction in sensitivity is relatively large, the output signal may be provided to the human-machine interface 109 to cause a warning signal to be provided to the user of the vehicle.

It should be understood that the ADAS system provided by control system 101 may perform many different driver assistance functions such as adaptive cruise control, autonomous emergency braking, lane departure warning, etc., and each of the driver assistance functions may have its own requirements for the capabilities of the sensing means 105. An example of the processes that may be performed at block 808 of method 800 and method 900 in respect of each driver assistance function of the ADAS system are illustrated in the flowchart of Fig. 10. I.e. the processes illustrated in Fig. 10 may be separately performed for each of the driver assistance functions that are provided by the ADAS system.

Initially at block 1001 it is determined whether a signal has been received indicating that a malfunctioning sensing means 105 has been identified at block 807, and if not, the driver assistance function continues to be performed at block 1003.

Alternatively, if it is determined at block 1001 that a malfunctioning sensing means 105 has been identified, then it is determined at block 1002 whether the driver assistance function can be safely performed when depending on the malfunctioning sensing means 105. For example, if the malfunctioning sensing means 105 has reduced sensitivity, but the reduced sensitivity is still sufficient for the correct operation of the driver assistance function, then the question at block 1002 may be answered in the affirmative, in which case the driver assistance function may continue to be performed at block 1003.

If it is determined at block 1002 that the driver assistance function cannot be safely performed when depending on the malfunctioning sensing means 105, it is determined at block 1004 whether the driver assistance function can be safely performed without the use of the malfunctioning sensing means 105. For example, the vehicle 100 may be provided with redundancy built into its sensing means 105, so that a driver assistance function that normally makes use of signals from several different sensing means 105 may be able to operate safely without the malfunctioning sensing means 105. If it is determined that the driver assistance function can be safely performed without the use of the malfunctioning sensing means 105, then the driver assistance function is performed at block 1005 in dependence on sensor signals received from other sensing means 105 and regardless of signals from the malfunctioning sensing means.

For example, when all of the sensing means 105 of Fig. 1 are operating correctly, the control system 101 may be configured to provide autonomous emergency braking in dependence on the presence of an object being indicated by the first sensor signal, the second sensor signal and a third sensor signal received from a third sensing means. For example, while all of the sensing means 105 are operating correctly, the vehicle 100 may be caused to brake automatically in dependence on a second vehicle 200 that is being tracked by the sensing means 105 having a velocity that is likely to cause it to collide with the vehicle 100. After the determined malfunction of a first sensing means 105, such as the radar device 106, the control system 101 may be configured to cause autonomous emergency braking in dependence on received sensor signals from a second sensing means 105, such as the lidar device 107, and a third sensing means 105, such as the camera 108, regardless of the signal from the first sensing means 105.

If it is determined at block 1004 that the driver assistance function cannot be safely performed without the malfunctioning sensing means 105, then an output signal may be provided at block 1006 to cause an indication to be provided to the user via a human-machine interface 110 that the driver assistance function is not available or that the performance of the sensing means 105 is degraded. The indication may also indicate that the maximum speed should be reduced, or that some other similar change should be made.

For purposes of this disclosure, it is to be understood that the controller(s) described herein can each comprise a control unit or computational device having one or more electronic processors. A vehicle and/or a system thereof may comprise a single control unit or electronic controller or alternatively different functions of the controller(s) may be embodied in, or hosted in, different control units or controllers. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) to implement the control techniques described herein (including the described method(s)). The set of instructions may be embedded in one or more electronic processors, or alternatively, the set of instructions could be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on one or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present disclosure is not intended to be limited to any particular arrangement. In any event, the set of instructions described above may be embedded in a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM and EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application.

The blocks illustrated in the Figs. 7 to 10 may represent steps in a method and/or sections of code in the computer program 602. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some steps to be omitted.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. For example, in some embodiments, one or more of the sensing means may provide a diagnostic output indicative of its own performance. In such embodiments the determination of a malfunction of a sensing means may be dependent on a combination of the result of the comparison of sensor signals, as has been described above, and the diagnostic output of that sensing means.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

CLAIMS1. A control system for a vehicle, the control system comprising one or more controllers, the control system configured to: receive a first sensor signal from a first sensing means of a vehicle, the first sensing means being of a first type; receive a second sensor signal from a second sensing means of the vehicle, the second sensing means being of a second type; determine a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected; and provide an output signal in dependence on the determined malfunction.
2. A control system according to claim 1, wherein the control system is configured to determine a distance to the object in dependence on the second sensor signal and determine the malfunction in dependence on said distance and an expected capability of the first sensing means.
3. A control system according to claim 1 or claim 2, wherein the first type comprises one of: a radar device; a camera; and a lidar device.
4. A control system according to any one of claims 1 to 3, wherein the first type and the second type each comprise a different one of: a radar device; a camera; and a lidar device.
5. A control system according to any one of claims 1 to 4, wherein the control system is configured to: provide the output signal to a human-machine interface for providing an alert to a user of the vehicle; and/or provide the output signal to a diagnostic interface of the vehicle for providing information of the vehicle.
6. A control system according to any one of claims 1 to 5, wherein, before the determination of the malfunction, the control system is configured to cause autonomous emergency braking in dependence on the first sensor signal indicating the presence of an object and the second sensor signal indicating the presence of the same object.
7. A control system according to claim 6, wherein in dependence on the determined malfunction of the first sensing means, the control system is configured to cause autonomous emergency braking in dependence on a received sensor signal from the second sensing means, regardless of the first sensing means.
8. A control system according to any one of claims 1 to 7, wherein: before the determination of the malfunction, the control system is configured to cause autonomous emergency braking in dependence on the presence of an object being indicated by the first sensor signal, the second sensor signal and a third sensor signal received from a third sensing means; and in dependence on the determined malfunction of the first sensing means, the control system is configured to cause autonomous emergency braking in dependence on received sensor signals from the second sensing means and the third sensing means, regardless of the first sensing means.
9. A control system according to claim 8, wherein the third sensing means comprises one of: a radar device; a camera; and a lidar device.
10. A control system according to any one of claims 1 to 9, wherein the control system is configured to provide the output signal to the first sensing means to cause said first sensing means to adjust a range of angles over which it is capable of positively detecting objects.
11. A control system according to any one of claims 1 to 10, wherein: the control system is configured to determine a magnitude of reduction in sensitivity of the first sensing means in dependence on sensor signals received from the first sensing means and from the second sensing means; and the output signal is indicative of the magnitude of reduction in sensitivity.
12. A control system according to any one of claims 1 to 11, wherein said malfunction of the first sensing means is determined in dependence on repeated occurrences of the second sensor signal being indicative of an object being positively detected when the first sensor signal is not indicative of the object being positively detected.
13. A vehicle comprising the first sensing means, the second sensing means and the control system of any one of the previous claims.
14. A method of monitoring status of a vehicle, the method comprising: receiving a first sensor signal from a first sensing means of a vehicle, the first sensing means being of a first type; receiving a second sensor signal from a second sensing means of the vehicle, the second sensing means being of a second type; determining a malfunction of the first sensing means in dependence on the second sensor signal being indicative of an object being positively detected and the first sensor signal not being indicative of the object being positively detected; and providing an output signal in dependence on said determining a malfunction.
15. A method according to claim 14, wherein the method comprises determining a distance to the object in dependence on the second sensor signal and determining the malfunction in dependence on said distance and an expected capability of the first sensing 15 means.
16. A method according to claim 14 or claim 15, wherein the first type comprises one of: a radar device; a camera; and a lidar device.
17. A method according to any one of claims 14 to 16, wherein the first type and the second type each comprise a different one of: a radar device; a camera; and a lidar device.
18. A method according to any one of claims 14 to 17, wherein the method comprises: providing the output signal to a human-machine interface for providing an alert to a user of the vehicle; and/or providing the output signal to a diagnostic interface of the vehicle for providing information during servicing of the vehicle.
19. A method according to any one of claims 14 to 18, wherein, before the determination of a malfunction, the method comprises providing an autonomous emergency braking in dependence on the first sensor signal indicating the presence of an object and the second sensor signal indicating the presence of the same object.
20. A method according to claim 19, wherein after the determined malfunction of the first sensing means, the method comprises providing autonomous emergency braking in dependence on a received sensor signal from the second sensing means, regardless of the first sensing means.
21. A method according to any one of claims 14 to 20, wherein: before the determination of a malfunction, the method comprises causing autonomous emergency braking in dependence on the presence of an object being indicated by the first sensor signal, the second sensor signal and a third sensor signal received from a third sensing means; and after the determined malfunction of the first sensing means, the method comprises causing autonomous emergency braking in dependence on received sensor signals from the second sensing means and the third sensing means, regardless of the first sensing means.
22. A method according to claim 21, wherein the third sensing means comprises one of: a radar device; a camera; and a lidar device.
23. A method according to any one of claims 14 to 22, wherein the method comprises providing the output signal to the first sensing means to cause said first sensing means to adjust a range of angles over which it is capable of positively detecting objects.
24. A method according to any one of claims 14 to 23, wherein: the method comprises determining a magnitude of reduction in sensitivity of the first sensing means in dependence on sensor signals received from the first sensing means and from the second sensing means; and the output signal is indicative of the magnitude of reduction in sensitivity.
25. A non-transitory computer readable medium comprising computer readable instructions that, when executed by a processor, cause performance of a method according to any one of claims 14 to 24.