Controlling a position of a vehicle
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- JAGUAR LAND ROVER LTD
- Filing Date
- 2024-08-08
- Publication Date
- 2026-06-24
AI Technical Summary
Existing vehicle control systems are unable to effectively maintain a safe distance from boundaries such as kerbs, barriers, and hedges, especially when lane markings are not present, leading to potential collisions.
A control system that uses sensors to detect the height characteristics of boundaries and dynamically adjusts the vehicle's position to maintain a minimum offset, preventing collisions with physical features while allowing cross-over near zero-height boundaries like lane markings.
The system effectively prevents collisions with physical boundaries by maintaining a safe distance based on boundary height, while allowing controlled cross-over near zero-height features, enhancing vehicle safety and control.
Smart Images
Figure EP2024072530_27022025_PF_FP_ABST
Abstract
Description
[0001] CONTROLLING A POSITION OF A VEHICLE
[0002] TECHNICAL FIELD
[0003] The present disclosure relates to controlling a position of a vehicle. Aspects of the invention relate a control system, a system, a vehicle, a method and computer readable instructions.
[0004] BACKGROUND
[0005] It is known for vehicles to have systems for detecting lane markings along a road, wherein the vehicle is controlled so as to stay within the limits of the detected lane markings to thereby assist the driver with maintaining their position along the road. However, not all driving surfaces are demarcated by lane markings and may include other features, such as barriers, kerbs and hedges, and such systems do not provide any assistance in controlling the vehicle so as to keep the vehicle an acceptable distance from other features that may be located along a surface on which the vehicle is travelling.
[0006] It is an aim of the present invention to address one or more of the disadvantages associated with the prior art.
[0007] SUMMARY OF THE INVENTION
[0008] Aspects and embodiments of the invention provide a control system, a system, a vehicle, a method and computer readable instructions as claimed in the appended claims.
[0009] This disclosure provides a technique for controlling the position of the vehicle as it travels along a driving surface. The technique detects features that represents boundaries of the driving surface and then controls the vehicle so as to maintain a distance from said boundaries depending on whether those boundaries have a zero or non-zero height.
[0010] According to an aspect of the present invention there is provided a control system for controlling a vehicle, the control system comprising one or more processors collectively configured to receive sensor data from one or more sensors of the vehicle, the sensor data comprising data indicative of one or more features in a vicinity of the vehicle. The one or more processors are collectively configured to identify, in dependence on the sensor data, one or more boundaries of a driving surface along which the vehicle is moving, and determine, in dependence on the sensor data, a height characteristic of the one or more boundaries. The one or more processors are collectively configured to determine, in dependence on the height characteristic of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle and the one or more boundaries, and output a control signal to cause the vehicle to maintain a position relative to the one or more boundaries such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset.
[0011] In this way, the position of the vehicle as it drives along a surface is controlled using a dynamically varying offset that determines how closely the vehicle can approach the boundaries of the surface depending on the height of the boundaries, to thereby prevent collisions with boundaries that represent physical features such as kerbs, barriers or ditches. In cases where the boundaries have a zero height characteristic, such as painted lane markings, an offset that allows certain amount of cross-over is permitted, whilst boundaries having a nonzero height characteristic require that the vehicle is maintained at a distance away from the boundary with no cross-over.
[0012] The control system comprises one or more controllers collectively comprising at least one electronic processor having an electrical input for receiving an input signal; and at least one memory device electrically coupled to the at least one electronic processor and having instructions stored therein; and wherein the at least one electronic processor is configured to access the at least one memory device and execute the instructions thereon so as to receive sensor data from one or more sensors of the vehicle, the sensor data comprising data indicative of one or more features in a vicinity of the vehicle; identify, in dependence on the sensor data, one or more boundaries of a driving surface along which the vehicle is moving; determine, in dependence on the sensor data, a height characteristic of the one or more boundaries; determine, in dependence on the height characteristic of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle and the one or more boundaries; and output a control signal to cause the vehicle to maintain a position relative to the one or more boundaries such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset.
[0013] Optionally, the one or more processors may be collectively configured to identify at least one of the boundaries as a physical edge if said boundary has a height characteristics less than or more than zero. Optionally, the one or more processors may be collectively configured to identify at least one of the boundaries as a lane marking if said boundary has a height characteristic approximately equal to zero.
[0014] Optionally, determining the minimum offset may comprises determining a first value of the minimum offset if the one or more boundaries have a height characteristic approximately equal to zero, and determining a second value of the minimum offset if the one or more boundaries have a height characteristic less than or more than zero, wherein the second value is greater than the first value.
[0015] In this way, boundaries such as lane markings will apply a first minimum offset, for example, the first minimum offset may be a negative offset such that a degree of cross-over is permitted. Boundaries that represent physical features such as kerbs, barriers, ditches or the like will apply a larger minimum offset, for example, a positive offset such that a distance between the vehicle and the boundary is maintained to prevent collision with these boundaries.
[0016] Optionally, the one or more processors may be collectively configured to identify a first boundary having a height characteristic approximately equal to zero, identify a second boundary having a height characteristics less than or more than zero, determine, in dependence on the sensor data, a distance between the first and second boundaries, and determine, in dependence at least in part on the determined distance, the value of the minimum offset, wherein the control signal causes the vehicle to maintain a position relative to the first boundary such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset therefrom. In this way, if there are multiple boundaries along the surface on which the vehicle is travelling, such as a set of lane markings and a kerb, the amount of offset is further determined based on the distance between these boundaries.
[0017] For example, the value of the minimum offset may be greater than the first value if the distance between the first and second boundaries is below a predetermined threshold. As such, if the two boundaries are close together, the amount of offset will be smaller than the offset applied for cases where there are only boundaries with non-zero height characteristics to thereby prevent any cross-over that could risk collision with the physical boundary.
[0018] As another example, the value of the minimum offset may be equal to or less than the first value if the distance between the first and second boundaries is above the predetermined threshold. As such, if the two boundaries are far apart, the amount of offset will be larger than the offset applied for cases where there are only boundaries with non-zero height characteristics since a larger deviation over the lane marking may be permitted.
[0019] Optionally, the one or more processors may be collectively configured to identify a first boundary having a height characteristic approximately equal to zero, identify a second boundary having a height characteristics less than or more than zero, determine a predicted time-to-cross in dependence on one or more of a tyre width of the vehicle, a steering wheel angle of the vehicle, a rate of change of steering wheel angle, the height characteristic of the second boundary, a width characteristic of the first boundary, a distance between the first and second boundary, a speed of the vehicle and a predicted time to collision between the vehicle and the second boundary, compare the predicted time-to-cross to a time-to-cross threshold, and determine a minimum offset in dependence on the comparison.
[0020] For example, if the predicted time-to-cross is below the time-to-cross threshold, the value of the minimum offset may be greater than the first value of minimum offset determined for boundaries having a height characteristic approximately equal to zero. If the predicted time-to-cross is above the time-to-cross threshold, the value of the minimum offset may be equal to or less than the first value of minimum offset determined for boundaries having a height characteristic approximately equal to zero.
[0021] In this way, if there are multiple boundaries along the surface on which the vehicle is travelling, such as a set of lane markings and a kerb, the amount of offset is adapted to the changing conditions as the vehicle travels along the surface.
[0022] It will be appreciated that the predicted time-to-cross may be determined using any suitable method. For example, the predicted time to cross may be determined using a linear model, wherein one or more of a tyre width of the vehicle, a steering wheel angle of the vehicle, a rate of change of steering wheel angle, the height characteristic of the second boundary, a width characteristic of the first boundary, a distance between the first and second boundary, a speed of the vehicle and a predicted time to collision between the vehicle and the second boundary are variables of said linear model. Optionally, the one or more processors may be collectively configured to receive data indicative of one or more operating conditions of the vehicle, and determine the minimum offset further in dependence on the one or more operating conditions of the vehicle.
[0023] In this way, the amount of offset is further adapted to the conditions in which the vehicle is operating, such as the terrain and weather conditions. For example, in wet or icy conditions, the amount of offset may be increased to account for any loss of traction that could be caused by these conditions.
[0024] Optionally, the minimum offset may be a distance from the one or more boundaries to a widest point of the vehicle.
[0025] In this way, the amount of offset is takes into account any peripheral attachments of the vehicle, such as trailers, that increase the effective width of the vehicle, such that the distance maintained between the boundaries and the vehicle does not result in collision between a boundary and any part of the vehicle and its attachments.
[0026] Optionally, the one or more processors may be collectively configured to output the control signal to a steering system of the vehicle, to thereby control the vehicle in accordance with the determined minimum offset.
[0027] According to another aspect of the invention, there is provided a system comprising the control system as mentioned above and a steering system of the vehicle.
[0028] According to yet another aspect of the invention, there is provided a vehicle comprising the system as mentioned above or the control system as mentioned above.
[0029] According to a further aspect of the invention, there is provided a method for controlling a vehicle. The method comprises receiving sensor data from one or more sensors of the vehicle, the sensor data comprising data indicative of one or more features in a vicinity of the vehicle, and identifying, in dependence on the sensor data, one or more boundaries of a driving surface along which the vehicle is moving. The method further comprises determining, in dependence on the sensor data, a height characteristic of the one or more boundaries, determining, in dependence on the height characteristic of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle and the one or more boundaries, and outputting a control signal to cause the vehicle to maintain a position relative to the one or more boundaries such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset.
[0030] According to a still further aspect of the invention, there is provided a computer readable instructions which, when executed by a computer, are arranged to perform the method as mentioned above.
[0031] 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.
[0032] BRIEF DESCRIPTION OF THE DRAWINGS
[0033] One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
[0034] Figure 1 shows a block diagram illustrating a control system according to an embodiment of the present invention;
[0035] Figure 2A shows a schematic illustration of a vehicle according to an embodiment of the present invention;
[0036] Figure 2B shows a schematic illustration of a rear-view of the vehicle of Figure 2a;
[0037] Figure 3 shows a first flow chart showing operations performed by the control system of Figure 1 according to an embodiment of the present invention;
[0038] Figure 4A shows a schematic illustration of a minimum offset determined during the operations performed by the control system of Figure 1 ;
[0039] Figure 4B shows a schematic illustration of a minimum offset determined during the operations performed by the control system of Figure 1 ;
[0040] Figure 5 shows a schematic illustration of the vehicle of Figure 2a during the operations performed by the control system of Figure 1 .
[0041] DETAILED DESCRIPTION
[0042] A control system 100 for controlling a vehicle in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figure 1 . As shown in Figure 2, the control system 100 is installed in a vehicle 200. The control system 100 comprises one or more controller 110.
[0043] With reference to Figure 1 , there is illustrated a control system 100 for a vehicle 200. The control system 100 comprises one or more controller 110.
[0044] The control system 100 is configured to receive sensor data 160 from one or more sensors 220A-G of the vehicle 200 to thereby identify one or more boundaries of a driving surface, and determine a minimum offset to be maintained between a part of the vehicle 200 and the boundaries of the driving surface based on characteristics of said boundaries. The control system 100 may then output a control signal 170 to control the vehicle 200 so as to maintain a position relative to the one or boundaries such that a part of the vehicle 200 is maintained at a distance greater than or equal to the minimum offset. In known advance driver assist systems, an offset which defines how close a vehicle is allowed to be to a boundary is defined. In some scenarios, a crossover, which defines how much over the boundary a vehicle is allowed to travel, is defined and is typically of the order of 10cm. In some scenarios, for example temporary roadside barriers, this can result in the vehicle interacting with features on, or near, the boundary. In the present system, the control system 100 of the vehicle 200 uses a dynamically varying offset which determines how closely the vehicle 200 can approach the boundaries of the driving surface, to thereby prevent interactions with the boundaries or features.
[0045] The control system 100 as illustrated in Figure 1 comprises one controller 110, although it will be appreciated that this is merely illustrative. The controller 110 comprises processing means 120 and memory means 130. The processing means 120 may be one or more electronic processing device 120 which operably executes computer-readable instructions. The memory means 130 may be one or more memory device 130. The memory means 130 is electrically coupled to the processing means 120. The memory means 130 is configured to store instructions, and the processing means 120 is configured to access the memory means 130 and execute the instructions stored thereon.
[0046] The controller 110 comprises an input means 140 and an output means 150. The input means 140 may comprise an electrical input 140 of the controller 110. The output means 150 may comprise an electrical output 340 of the controller 305. The input 140 is arranged to receive sensor data 160 from one or more sensors of the vehicle 200. The sensor data 160 is an electrical signal which is indicative of one or more features in the vicinity of the vehicle 200 and the characteristics thereof. For example, the sensor data 160 may comprise one or more of a height characteristic of a feature, a width characteristic of a feature, and a position characteristic of a feature. The one or more sensors may be any sensor configured to detect features within the vicinity of the vehicle 200, from which the characteristics the features can be derived. For example, the one or more sensors may comprise one or more of a radar system, such as a pulsed radar system or frequency modulated continuous wave (FMCW) radar system, a lidar system, one or more image sensors, and an ultrasonic sensor system.
[0047] Optionally, the input 140 may be configured to receive an operating conditions signal 165 from one or more further sensors of the vehicle 200. The operating conditions signal 165 is an electrical signal which is indicative of one or more operational conditions of the vehicle 200. For example, the operating conditions signal 165 may comprise one or more of a terrain mode signal indicative of a terrain mode of the vehicle, a temperature signal from a temperature sensor indicative of the surrounding temperature, and a signal indicative of the activation of the windscreen wipers by a user. The operating conditions signal 165 may also comprise a speed signal from a speed sensor indicative of the speed of the vehicle 200, and a steering wheel angle signal from an angle sensor indicative of a rotation of the steering wheel.
[0048] The output 150 is arranged to output a control signal 170 to cause the vehicle 200 so as to maintain a position relative to one or boundaries of a driving surface such that a part of the vehicle 200 is maintained at a distance greater than or equal to a minimum offset. For example, the control signal 170 may control a steering system of the vehicle 200 in accordance with the minimum offset.
[0049] Figure 2A illustrates a vehicle 200 according to an embodiment of the present invention. Figure 2B illustrates a rear-view of the vehicle 200 of Figure 2A. The vehicle 200 comprises controller 110 as illustrated in Figure 1. The controller 1 10 is shown as mounted within the vehicle 200 and is in communication with one or more sensors 220A-G distributed about the vehicle 200, such that the sensor data 160 can be received from the one or more sensors 220A-G. It will of course be appreciated that the sensors 220A-G shown in Figures 2A-B are merely illustrative and there may be any number of sensors provided at any suitable location about the vehicle 200. The control system 110 is in further communication with a steering system 240 located within the vehicle 200 such that the control signal 170 can be transmitted to the steering system 240.
[0050] Vehicle 200 may be a known human controlled vehicle or an EGO vehicle, i.e., a vehicle that is equipped with autonomous or semi-autonomous driving technology and is capable of sensing and navigating its environment without direct input from a human driver.
[0051] Figure 3 illustrates a method 300 according to an embodiment of the invention. The method 300 is a method of controlling of a vehicle 200, such as the vehicle 200 illustrated in Figures 2A and 2B and with further reference to Figure 5. In particular, the method 300 is a method of controlling a vehicle 200 so as to maintain a position relative to one or more boundaries of a driving surface such that a part of the vehicle 200 is maintained at a distance greater than or equal to a minimum offset. A boundary may be any feature that defines an edge or limit of the surface along which the vehicle 200 is travelling, including but not limited to, painted lane markings, a region of grass or ground level vegetation, the edge of a paved surface, a kerb, a barrier, a traffic cone, a wall, ditches, hedges, or any other feature that demarcate a driving surface. The boundary may be a permanent, or temporary, feature.
[0052] The method 300 may be performed by the system 100 illustrated in Figure 1. In particular, the memory 130 may comprise computer-readable instructions which, when executed by the processor 120, perform the method 300 according to an embodiment of the invention.
[0053] In the example shown in Figure 5, the vehicle 200 is travelling along a driving surface 500 having a plurality of features in the vicinity of the vehicle 200, in particular, a set of painted line markings 520 and a plurality of barriers 540. Whilst two types of features are shown, both of which may be categorised as boundaries of the driving surface 500, it will be appreciated that this is merely illustrative and there may be any number of features of various types in the vicinity of the vehicle 200, which may or may not be boundaries of the driving surface 500 (e.g., other vehicles).
[0054] At step 310, the controller 110 is configured to receive sensor data from one or more sensors 220A-G of the vehicle 200. The sensor data is received as an input signal 160 at the input means 140 of the controller 110 and comprises data indicative of one or more features in the vicinity of the vehicle 200 and the characteristics thereof. For example, the one or more sensors 220A-G may comprise an image sensor system, from which one or more features within the vicinity of the vehicle 200 can be identified and characteristics such as height, width and relative position can be derived. As a further example, in Figure 5, the sensor 220C may be an image sensor having a field of view generally denoted by 560, such that it detects the painted line markings 520 and the barriers 540 in front of the vehicle 200. It will however be appreciated that the one or more sensors 220A-G may comprise a single type of sensor or a combination of sensor types suitable for identifying features within the vicinity of the vehicle 200 and determining the characteristics described herein.
[0055] At step 320, the controller 1 10 is configured to identify one or more boundaries of a driving surface along which the vehicle 200 is moving based on received sensor data 160. In this respect, the processing means 120 receives the input signal 160 from the input means 140, and upon executing the instructions stored in the memory means 130, identifies the one or more boundaries. For example, in Figure 5, the painted line markings 520 and the barriers 540 may be identified as boundaries of the driving surface 500.
[0056] At step 330, the controller 1 10 is configured to determine one or more characteristics of the one or more boundaries from the sensor data 160, the one or more characteristics at least comprising a height characteristic. In this respect, the sensor data 160 is processed by the processing means 120 to determine a height characteristic of the one or more boundaries identified at step 320. For example, in the case of sensor data 160 received from one or more image sensors, a height characteristic may be determined based on a pixel relationship between the height and depth of the image sensor. Optionally, the processing means 120 may be configured to identify at least one of the boundaries as a physical edge if said boundary has a height characteristic less than or more than zero (i.e., relative to the horizontal plane of the driving surface). For example, a boundary having a height characteristic more than zero, such as a kerb, barrier, wall, hedge or traffic cone, may be identified as a physical edge of the driving surface. Similarly, a boundary having a height characteristic less than zero, such as ditch or hole, may also be identified as a physical edge of the driving surface. The controller 1 10 may also be configured to identify at least one of the boundaries as a lane marking (also referred to as a “virtual edge”) if said boundary has a height characteristic approximately zero. For example, a boundary having a height characteristic approximately equal to zero, such as painted lane markings, the edge of a paved surface or a region of grass, may be identified as a lane marking or “virtual edge”. As one example, a height characteristic approximately equal to zero may be any height between -1 cm to 1 cm relative to the horizontal plane of the driving surface. It will of course be appreciated that the threshold for identifying a boundary as a “virtual edge” may depend on the size of the tyres of the vehicle 200, and in particular, the size of the tyre wall. As such, a height characteristic approximately equal to zero may be calibrated to be any height within a given range, depending on the size of the tyres and their ability to cross over features having that height profile without reducing the composure of the vehicle.
[0057] As such, in the example shown in Figure 5, the processing means 120 will identify a first boundary having a height characteristic approximately equal to zero (e.g., the painted line markings 520), and a second boundary having a height characteristic less than or greater than zero (e.g., barriers 540).
[0058] Optionally, the processing means 120 may be configured to determine one or more further characteristics comprising one or more of a width characteristic of the one or more boundaries, and a position characteristic of the one or more boundaries relative to the vehicle 200. For example, in the Figure 5 example, the processing means 120 may be configured to determine a width of the first boundary 520, and a position of the first boundary 520 and the second boundary 540, such that it is determined that the first boundary 520 is closer to the vehicle 200.
[0059] At step 340, the processing means 120 is configured to determine, based at least on the height characteristics of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle 200 and the one or more boundaries. In this respect, the minimum offset is the minimum distance that should be maintained between a part of the vehicle 200 and the one or more boundaries. It will however be appreciated that the minimum offset may be a positive value, such that the vehicle 200 is maintained at least that distance from the one or more boundaries, or a negative value, such that an acceptable amount of cross over is permitted.
[0060] For example, the processing means 120 may be configured to determine a first value of the minimum offset if the one or more boundaries if the one or more boundaries having a height characteristic approximately equal to zero, and a second value of the minimum offset if the one or more boundaries have a height characteristic less than or more than zero, wherein the second value is greater than the first value. An example is provided in Figures 4A and 4B by way of illustration. As shown in Figure 4A, a boundary 440 in the form of a painted lane marking is providing along a driving surface 420. As the height characteristic of the lane marking 440 is approximately equal to zero, a first value A of minimum offset is determined such that the tyre 400 of the vehicle is permitted to cross over the lane marking 440 by that given amount. That is to say, the first value A of minimum offset is a negative value, for example, the first value A of minimum offset may be -10cm. As shown in Figure 4B, a boundary 460 in the form of a physical barrier is provided along the driving surface 420. As the height characteristic of the barrier 460 is more than zero, a second value B of minimum offset is determined such that the tyre 400 of the vehicle is maintained at that distance from the barrier 460. That is to say, the second value B of minimum offset is a positive value, for example, the second value B of minimum offset may be 10cm.
[0061] Optionally, the processing means 120 may be configured to further determine the value of the minimum offset based on one or more operating conditions of the vehicle 200. In this respect, one or more operating conditions of the vehicle 200 may be received as an input signal 165 at the input means 140 of the controller 110 and comprises data indicative of one or more operating conditions of the vehicle 200. For example, the operating conditions signal 165 may comprise data indicative of one or more of a terrain mode of the vehicle (e.g., input by the user via a human-machine interface), a temperature of the surrounding area, and an activation of the windscreen wipers. The processing means 120 may then be configured to process the one or more operating conditions 165 and adjust the minimum offset determined at step 340 in dependence on said operating conditions. For example, if the operating conditions signal 165 comprises data indicative of wet or icy conditions (e.g., via a snow terrain mode, a temperature below 0°C, orthe activation of the windscreen wipers), the minimum offset may be increased to account for any potential reduction in traction between the tyres of the vehicle 200 and the driving surface. The amount of offset increase in an example is by a predetermined amount, dependent on the type of condition detected. Optionally, where two or more boundaries having different height characteristics are identified in the vicinity of the vehicle 200, wherein a first boundary having a zero height characteristic (e.g., painted lane markings 520) is positioned between the vehicle 200 and a second boundary having a non-zero height characteristic (e.g., barriers 540), as illustrated in the example of Figure 5, the processing means 120 may be configured to further determine the value of the minimum offset based further characteristics of the boundaries, one or more operating conditions of the vehicle 200, and / or one or more properties of the vehicle 200.
[0062] As one example, the processing means 120 may be configured to determine a distance between the two boundaries based on a position characteristic of the boundaries relative to the vehicle 200. For example, in Figure 5, the distance X between the painted lane markings 520 and the barriers 540 may be determined based on the positions of those features relative to the vehicle 200. The processing means 120 may then be configured to further determine the value of the minimum offset to be maintained between a part of the vehicle 200 and the closest boundary (e.g., the painted lane markings 520) based on the distance between the two boundaries. For example, if the distance between the two boundaries is below a predetermined threshold, the value of the minimum offset may be greater than the first value A of minimum offset determined for boundaries having a height characteristic approximately equal to zero. That is to say, if the boundaries are close together, the amount of offset may be greater than the offset applied for boundaries having a zero height characteristic to prevent any cross-over that could risk an interaction with the second boundary. For example, ifthe first value A of minimum offset is -10cm, as described above, the processing means 120 may be configured to determine a minimum offset of -5cm. Conversely, ifthe distance between the two boundaries is above the predetermined threshold, the value of the minimum offset may be equal to or smaller than the first value A of minimum offset determined for boundaries having a height characteristic approximately equal to zero. That is to say, if the boundaries are far apart, the amount of offset may be the same as or less than the offset applied for boundaries having a zero height characteristic, since some amount of travel over the first boundary is unlikely to risk a collision with the second boundary. For example, if the first value A of minimum offset is -10cm, as described above, the processing means 120 may be configured to determine a minimum offset of -10cm or -15cm. In some cases, the processing means 120 may be configured to determine a minimum offset that does not permit the vehicle to cross over the boundary having a zero characteristic by a distance greater than the width of the tyre. For example, if the tyre is 20.5cm wide, the minimum offset may be -20cm. It will be appreciated that the predetermined threshold of distance may be any suitable threshold, for example, the predetermined threshold may be a value between 10cm and 30cm. It will also be appreciated that the predetermined threshold distance may depend on different factors such as the width of the vehicle 200, width of the tyres and distance between the body of the vehicle 200 and features such as the door mirrors.
[0063] As a further example, the processing means 120 may be configured to determine a predicted time-to-cross in dependence on one or more of the width characteristic of the first boundary, the height characteristic of the second boundary, a distance between the first and second boundary, a speed of the vehicle 200, a tyre width of the vehicle 200, a steering wheel angle of the vehicle 200, a rate of change of steering wheel angle and a predicted time-to-collision between the vehicle 200 and the second boundary. In this respect, it will be understood by the skilled person that the time-to-cross corresponds to the time it would take the vehicle 200 to cross the first boundary and reach the second boundary, and that time-to-cross calculations may be performed using a number of suitable methods.
[0064] For example, the predicted time-to-cross may be determined using a linear model, wherein one or more of the width characteristic of the first boundary, the height characteristic of the second boundary, a distance between the first and second boundary, a speed of the vehicle 200, a tyre width of the vehicle 200, a steering wheel angle of the vehicle 200, a rate of change of steering wheel angle, and a predicted time-to-collision between the vehicle 200 and the second boundary are variables of said linear model. The processing means 120 may then be configured to further determine the value of the minimum offset to be maintained between a part of the vehicle 200 and the closest boundary (e.g., the painted lane markings 520) based on the predicted time- to-cross. For example, the predicted time-to-cross may be compared to a time-to-cross threshold, the value of the minimum offset being determined in dependence on that comparison. If the predicted time-to-cross is below the time-to-cross threshold, the value of the minimum offset may be greater than the first value A of minimum offset determined for boundaries having a height characteristic approximately equal to zero, to thereby prevent any cross-overthat could risk a collision with the second boundary. Conversely, if the predicted time-to-cross is above the time-to-cross threshold, the value of the minimum offset may be equal to or less than the first value A of minimum offset determined for boundaries having a height characteristic approximately equal to zero, since some amount of travel over the first boundary is unlikely to risk a collision with the second boundary. It will be appreciated that the time-to-cross threshold may be any suitable threshold, for example, the time-to-cross threshold may be a value between 0.8s and 2.5s.
[0065] Once the processing means 120 has determined the minimum offset, the controller 110 outputs, at step 350, a control signal 170 to cause the vehicle 200 so as to maintain a position relative to one or boundaries of a driving surface such that a part of the vehicle 200 is maintained at a distance greater than or equal to a minimum offset. For example, the control signal 170 may be output to the steering system 240 of the vehicle 200, to thereby control the vehicle in accordance with the determined minimum offset.
[0066] In doing so, the position of the vehicle 200 as it drives along a surface is controlled using a dynamically varying offset that determines how closely the vehicle 200 can approach the boundaries of the surface depending on the height of the boundaries, to thereby prevent collisions with boundaries that represent physical edges such as kerbs, barriers or ditches. In cases where the boundaries have a zero height characteristic, such as painted lane markings, an offset that allows certain amount of cross-over is permitted, whilst boundaries having a nonzero height characteristic require that the vehicle 200 is maintained at a distance away from the boundary with no cross-over.
[0067] Whilst Figures 4A and 4B show a tyre as being the part of the vehicle 200 that maintains a position greater than or equal to the minimum offset, it will be appreciated that any suitable part of the vehicle may be maintained at a distance greater than or equal to the minimum offset. For example, the part of the vehicle 200 may be any part representing the outermost point across the width of the vehicle 200, including but not limited to, the tyres of the vehicle 200, the body of the vehicle 200, or an attachment to the rear of the vehicle 200 such as a bike rack or trailer. In cases where the part of the vehicle 200 corresponds to an attachment to the rear of the vehicle 200, it will be appreciated that the dimensions of the attachment may be input to the controller 100 by the user (e.g., via a human-machine interface), such that the control signal 170 accounts for this increase in width. For example, if a trailer is attached to the rear of the vehicle 200 that increases the effective width of the vehicle 200 by 10cm beyond the tyres on each side, the control signal 170 output by the controller 1 10 will factor in this additional width such that the distance defined by the minimum offset will be maintained between the boundary and the widest point of the vehicle 200 (i.e., the trailer). For example, if the minimum offset is determined to be +10cm, the control signal 170 may cause the steering system 240 of the vehicle 200 to maintain the tyres of the vehicle 200 at distance of 20cm from the boundary to ensure that the trailer is maintained at a distance greaterthan or equal to the minimum offset. Alternatively, based on the width of attachment (e.g., a trailer), the control system 170 may take the width of the vehicle 200 to be that of trailer, and apply the minimum offset to that width.
[0068] 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.
Claims
CLAIMS1 . A control system for controlling a vehicle, the control system comprising one or more processors collectively configured to: receive sensor data from one or more sensors of the vehicle, the sensor data comprising data indicative of one or more features in a vicinity of the vehicle; identify, in dependence on the sensor data, one or more boundaries of a driving surface along which the vehicle is moving; determine, in dependence on the sensor data, a height characteristic of the one or more boundaries; determine, in dependence on the height characteristic of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle and the one or more boundaries; and output a control signal to cause the vehicle to maintain a position relative to the one or more boundaries such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset.
2. A control system according to claim 1 , wherein the one or more processors are collectively configured to identify at least one of the boundaries as a physical edge if said boundary has a height characteristics less than or more than zero.
3. A control system according to claims 1 or 2, wherein the one or more processors are collectively configured to identify at least one of the boundaries as a lane marking if said boundary has a height characteristic approximately equal to zero.
4. A control system according to any preceding claim, wherein determining the minimum offset comprises: determining a first value of the minimum offset if the one or more boundaries have a height characteristic approximately equal to zero; and determining a second value of the minimum offset if the one or more boundaries have a height characteristic less than or more than zero, wherein the second value is greater than the first value.
5. A control system according to any preceding claim, wherein the one or more processors are collectively configured to: identify a first boundary having a height characteristic approximately equal to zero; identify a second boundary having a height characteristics less than or more than zero; determine, in dependence on the sensor data, a distance between the first and second boundaries; and determine, in dependence at least in part on the determined distance, the value of the minimum offset, wherein the control signal causes the vehicle to maintain a position relative to the first boundary such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset therefrom.
6. A control system according to claim 5 when dependent on claim 4, wherein the value of the minimum offset is greaterthan the first value if the distance between the first and second boundaries is below a predetermined threshold.
7. A control system according to claim 6, wherein the value of the minimum offset is equal to or less than the first value if the distance between the first and second boundaries is above the predetermined threshold.
8. A control system according to claim 4, wherein the one or more processors are collectively configured to: identify a first boundary having a height characteristic approximately equal to zero; identify a second boundary having a height characteristics less than or more than zero; determine a predicted time-to-cross in dependence on one or more of a tyre width of the vehicle, a steering wheel angle of the vehicle, a rate of change of steering wheel angle, the height characteristic of the second boundary, a width characteristic of the first boundary, a distance between the first and second boundary, a speed of the vehicle and a predicted time to collision between the vehicle and the second boundary; compare the predicted time-to-cross to a time-to-cross threshold; and determine a minimum offset in dependence on the comparison.
9. A control system according to any preceding claim, wherein the one or more processors are collectively configured to: receive data indicative of one or more operating conditions of the vehicle; and determine the minimum offset further in dependence on the one or more operating conditions of the vehicle.
10. A control system according to any preceding claim, wherein the minimum offset is a distance from the one or more boundaries to a widest point of the vehicle.11 . A control system according to any preceding claim, wherein the one or more processors are collectively configured to output the control signal to a steering system of the vehicle, to thereby control the vehicle in accordance with the determined minimum offset.
12. A system comprising the control system of any preceding claim and a steering system of the vehicle.
13. A vehicle comprising the system of claim 12 or the control system of claims 1 - 11 .
14. A method for controlling a vehicle, the method comprising: receiving sensor data from one or more sensors of the vehicle, the sensor data comprising data indicative of one or more features in a vicinity of the vehicle; identifying, in dependence on the sensor data, one or more boundaries of a driving surface along which the vehicle is moving;determining, in dependence on the sensor data, a height characteristic of the one or more boundaries; determining, in dependence on the height characteristic of the one or more boundaries, a minimum offset to be maintained between a part of the vehicle and the one or more boundaries; and outputting a control signal to cause the vehicle to maintain a position relative to the one or more boundaries such that the part of the vehicle is maintained at a distance greater than or equal to the minimum offset.
15. Computer readable instructions which, when executed by a computer, are arranged to perform a method according to claim 14.