Steering angle control

Abstract

A control system receives a position signal at least partly based on data from a first sensor such as a camera 104 indicating a vehicle’s position relative to an obstacle (300, Figure 5) such as a ker

Description

TECHNICAL FIELD The present disclosure relates to steering control. Aspects of the invention relate to a control system, a vehicle system comprising such a control system, a vehicle comprising such a control and / or vehicle system, and a method. BACKGROUND It is known to provide steering feedback and / or control signals regarding a car’s position relative to an obstacle. For example, a sensor-based system can provide audible and / or haptic feedback to a driver as a vehicle approaches an obstacle. 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, a vehicle system, a vehicle, a method, and computer readable instructions. According to an aspect of the present invention, there is provided a control system for a vehicle, the control system comprising one or more processors collectively configured to: receive a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle; determine, in dependence on the position signal: a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; and a second path that will cause at least the first road wheel(s) of the vehicle to encounter the obstacle at or above a minimum predefined approach angle; and output: a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the first road wheel(s) do not encounter the obstacle at an angle between parallel with the obstacle and the minimum predefined approach angle; and / or an instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the first road wheel(s) do not encounter the obstacle at an angle between parallel with the obstacle and the minimum predefined approach angle. According to a further aspect of the present invention there is provided a control system for a vehicle, the control system comprising one or more processors collectively configured to: receive a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle; determine, in dependence on the position signal: 1 a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; and a second path that will cause at least the first road wheel(s) of the vehicle to encounter the obstacle at or above a minimum predefined approach angle; and output: a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle; and / or an instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as to cause the first road wheel(s) of the vehicle to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) of the vehicle encounters the obstacle at or above the minimum predefined approach angle. 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 implement the preceding aspect. Outputting such a steering control signal and / or instruction signal may assist in reducing the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. The obstacle can be, for example, a kerb, or a kerb-like obstacle such as a step, a ridge, or a wall of a trench or ditch. For example, wheel damage is more likely if the wheel approaches the kerb at a shallow angle. Optionally, the steering control signal and / or the instruction signal is indicative of a predicted path of the first road wheel(s) of the vehicle based on a steering signal indicative of a steering angle of the at least one steerable road wheel of the vehicle. The predicted path being based on the steering signal may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the steering control signal and / or the instruction signal is indicative of a relationship between the predicted path, and the first and second paths. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the steering control signal and / or the instruction signal is indicative of a steering adjustment to be made to the steering angle, such that the vehicle follows a trajectory in dependence on the first path or the second path. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the first path will cause a portion of the vehicle’s bodywork to avoid the obstacle. This may assist in the control of the vehicle so as to further reduce the chance of bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the first road wheel(s) comprises at least one of the steerable road wheel(s). Optionally, the one or more processors are collectively configured to update the first path and / or the second path based at least partly on changes to the position signal as the vehicle moves relative to the obstacle. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the one or more processors are collectively configured to determine whether the vehicle is capable of steering along either or both of the first and second paths based on the vehicle’s position, wherein the steering control signal and / or the instruction signal is indicative of that determination. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the steering control signal and / or the instruction signal is indicative of one of more of: the steering angle; the first path and / or a first region at least partly bounded by the first path; the second path and / or a second region at least partly bounded by the second path; a third region at least partly bounded by the first and second paths; whether the steering angle will result in the first road wheel(s) avoiding the obstacle; whether the steering angle will result in the first road wheel(s) encountering the obstacle at or above the minimum approach angle; and one or more correction inputs to apply to the steering angle to ensure that at least one road wheel of the vehicle avoids the obstacle and / or encounters the obstacle at or above the minimum approach angle. Each of these may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the one or more processors are collectively configured to: receive a speed signal indicative of a speed of the vehicle; and determine the steering control signal and / or the instruction signal at least partly in dependence on the speed signal. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the one or more processors are collectively configured to, based on the speed signal, only output the steering control signal and / or the instruction signal when the speed of the vehicle is below a threshold. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the one or more processors are collectively configured to receive user input from a user interface, the user input being indicative of whether the user wishes the road wheel to avoid the obstacle or to encounter the obstacle at or above a minimum approach angle, wherein the steering control signal and / or the instruction signal is indicative of an angle of the steerable road wheel(s) that will cause the road wheel(s) to avoid the obstacle or to encounter the obstacle at or above the minimum approach angle, based on the user input. This may assist the user in controlling the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the instruction signal comprises feedback information for providing a user with feedback regarding the relationship between at least the steering angle and the at least one of the first and second paths. This may assist the user in controlling the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the one or more processors are collectively configured to: determine that the at least one road wheel of the vehicle will encounter the obstacle at less than the minimum approach angle; and in dependence on that determination, output: a warning signal to instruct a user to use the brakes of the vehicle to slow and / or stop the vehicle before the at least one road wheel encounters the obstacle; and / or a braking signal to cause brakes of the vehicle to slow and / or stop the vehicle before the at least one road wheel encounters the obstacle. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the data is indicative of at least one dimension and / or shape-based characteristic of the obstacle. This may assist in identifying the obstacle and / or in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. Optionally, the position comprises one or more of: an angle of the vehicle, or of a component of the vehicle, relative to the obstacle; and a distance of the vehicle, or of a component of the vehicle, from the obstacle. This may assist in the control of the vehicle so as to further reduce the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. According to a further aspect of the present invention, there is provided a vehicle system comprising the control system. Optionally, the vehicle system comprises at least a first sensor for sensing an obstacle and outputting the position signal indicative of the vehicle’s position relative to the obstacle. According to a further aspect of the present invention, there is provided a vehicle comprising the vehicle system or the control system. According to a further aspect of the present invention, there is provided a method comprising: receiving a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle; determining, in dependence on the position signal: a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; and a second path that will cause at least the first road wheel(s) to encounter the obstacle at or above a minimum predefined approach angle; and outputting: a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle; and / or an instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as to cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle. The method may assist in reducing the chance of one or more wheels, tyres, and / or bodywork of the vehicle being damaged by interacting with the obstacle. The obstacle can be, for example, a kerb, or a kerb-like obstacle such as a step, a ridge, or a wall of a trench or ditch. According to a further aspect of the present invention, there are provided computer readable instructions that, when executed by a computer, are arranged to perform the method. According to a further aspect of the present invention, there is provided a control system for a vehicle, the control system comprising one or more processors collectively configured to: receive a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle; determine, in dependence on the position signal: a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; and a second path that will cause at least the first road wheel(s) of the vehicle to encounter the obstacle at or above a minimum predefined approach angle; and output: a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the first road wheel(s) do not encounter the obstacle at an angle between parallel with the obstacle and the minimum predefined approach angle; and / or an instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the first road wheel(s) do not encounter the obstacle at an angle between parallel with the obstacle and the minimum predefined approach angle. 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: Figure 1 shows a front perspective view of a vehicle in accordance with an embodiment of the invention; Figure 2 shows a schematic plan view of the vehicle of Figure 1, comprising a control system in accordance with an embodiment of the invention; Figures 3 and 4 show a schematic plan view of the vehicle of Figures 1 and 2 approaching a kerb; Figure 5 shows a simplified front view of a wheel of the vehicle of Figures 1 to 4 engaging a kerb, with the rest of the vehicle omitted for clarity; Figures 6 to 8 show plan views of the wheel and kerb of Figure 5; Figure 9 shows a schematic plan view of the vehicle of Figures 1 to 4 approaching a kerb; Figures 10 and 11 showed schematic plan views of the vehicle of Figures 1 to 4; Figures 12 and 13 show a schematic view of an image presented on a display of the vehicle of Figures 1 to 4 approaching a kerb; Figure 14 shows a detail from Figure 13; Figure 15 shows a schematic view of an image shown on the display of the vehicle of Figures 1 to 4, the vehicle having followed a path to avoid the kerb; Figure 16 shows a schematic view of an image shown on the display of the vehicle of Figures 1 to 4, the vehicle having followed a path to mount the kerb; Figure 17 shows a schematic plan view of the vehicle of Figures 1 to 4 approaching a kerb; Figures 18 to 28 show various schematic views of images shown on the display of the vehicle of Figures 1 to 4, according to different implementations; Figure 29 shows a schematic plan view of the vehicle of Figures 1 to 4 approaching a kerb; Figure 30 shows a schematic view of the vehicle of Figures 1 to 4 comprising a vehicle system in accordance with an embodiment of the invention; and Figure 31 shows a method according to an embodiment of the invention. DETAILED DESCRIPTION Wherever the word “kerb” is used throughout this specification, it includes any object that has similar characteristics to a kerb. For example, a low ridge, a railway sleeper, a step, or a line of stones, rising from an adjacent surface (such as an adjacent road surface) and having a similar scale to a kerb, may be treated as a kerb or kerb-like object. Similarly, a rising wall of a trench or a ditch can be considered to have similar characteristics to a kerb. One exemplary but non-limiting definition of a kerb or kerb-like obstacle for a particular vehicle is a step or wall rising from a road or other surface, which is low enough that the vehicle is capable of slowly driving up onto it, without damage to the vehicle. The term “user / driver” is used herein to describe a user who can interact with, and receive instructions under the control of, the control system 100. The user / driver will often be the driver of the vehicle, but this is not necessarily the case, especially in autonomous and semi-autonomous vehicles where there may be some blurring between the role of driver and non-driver passenger. For this reason, “user” or “user / driver” as used herein means a passenger of the vehicle who is in the position of responding to information and instructions output via the control system 100. With reference to the drawings, there is described a control system 100 in accordance with an embodiment of the invention, and a vehicle 200 within which control system 100 is installed. The control system 100 can form part of a vehicle system 600 (see Figure 30, described below) comprising any necessary sensor(s), data communication system(s), and power supply system(s). The vehicle 200 is a road-going car. In other implementations, vehicle 200 can take the form of a van, sports utility vehicle, truck, or any other vehicle. The vehicle 200 includes steerable front wheels 202 and 204 and non-steerable rear wheels 206 and 208. In other implementations, the front wheels are fixed and the rear wheels are steerable. In other yet other implementations, and the front and rear wheels are steerable, optionally by different amounts. Although vehicle 200 has four road wheels, it will be appreciated that a greater or lesser number of road wheels may be employed in other implementations. Control system 100 comprises a controller 102, as described below in more detail below with reference to Figure 30. Control system 100 is operatively connected to a first sensor 104 by way of a suitable data connection. The data connection can take the form of, for example, a CAN bus connection to transmit data from the first sensor 104 to the control system 100, although any other suitable hardware and / or data transmission protocol or format can be used. The data sent to the control system 100 by way of the data connection can include a position signal 106, the position signal 106 being indicative of the vehicle’s position relative to an obstacle, as described in more detail below. The position can include an angle of the vehicle, or of a component of the vehicle (such as one or more wheels of the vehicle), relative to the obstacle. Alternatively, or in addition, the position can include a distance of the vehicle, or of a component of the vehicle (such as one more wheels of the vehicle), from the obstacle. The first sensor 104 can generate the position signal 106 using any suitable sensor technology or combination of sensor technologies. For example, first sensor 104 can comprise a lidar sensor installed in the vehicle 200 at a position that enables first sensor 104 to identify a location of vehicle 200 relative to an obstacle, such as a kerb. Other sensor types can include cameras (including those operating inside and / or outside the visible spectrum), radar sensors, ultrasonic sensors (e.g., PDC sensors), and microwave sensors. One or more of each sensor type can be used, and sensors can be used in any combination. The skilled person will appreciate that certain sensor types operate in conjunction with a corresponding transmitter. For example, radar, ultrasonic, and microwave based sensors require the corresponding transmission of radar, ultrasonic, and microwave signals that are reflected by the environment and captured / processed by the corresponding sensor to generate the position signal 106. Additionally, it will be appreciated that the position signal 106 can be at least partly processed by the sensor 104 before transmission to the control system 100. For example, the position signal 106 can represent any suitable transformation of the raw data sensed by first sensor 104. For example, the raw data sensed by a lidar sensor can be processed into a two- or three-dimensional model, and the position signal 106 can be provided in the form of data representing the two- or three-dimensional model. The model can be a complete model of what is sensed or can be filtered or adjusted to simplify what is presented to the user / driver. Alternatively, the position signal 106 can take the form of raw or processed data generated by the sensor, which is subsequently processed by the control system 100 or by one or more other processor(s) operatively connected to the first sensor 104 and the control system 100. In the implementation of Figure 2, the first sensor 104 takes the form of a video camera. As best shown in Figure 3, the first sensor 104 is positioned within a passenger-side mirror housing 210 to look downward and to the side of the vehicle 200. As indicated by the field of view 212 (see, e.g., Figures 1,3, and 4) of the sensor 104, the sensor 104 has a relatively wide field of view, which assists in maximising its operative range. The sensor 104 is disposed on the passenger side of the vehicle 200, such that it captures images along that side. This is because any obstacle, such as a kerb, that the user / driver is likely to want to park near, or drive over, is more likely to be on the passenger side of the vehicle 200. It will be appreciated, however, that one or more of the sensors 104, such as one or more cameras, can be provided on the user / driver’s side of the vehicle, and / or at any other position around the vehicle. Non-limiting examples of positions for such sensors include within wheel arch overhangs, within door and tailgate handles, around the bodywork of the vehicle (including within bumpers), on the vehicle’s roof, and within grills or other suitably located decorative and / or functional features. Returning to Figure 2, the vehicle 200 also includes an infotainment system 108, which includes a display 110 and an audio system 112. The control system 100 is operatively connected to the infotainment system 108 by way of a suitable data connection. The control system 100 is configured to output one or control signals to the infotainment system 108, as described in more detail below. The infotainment system 108 can include, for example, its own controller (not shown) comprising one or more processors and memory, and can optionally process data received from the control system 100 before outputting it to the user / driver. The position signal 106 output by the sensor 104 is indicative of the position of vehicle 200 relative to an obstacle. For example, Figure 3 illustrates an example of the vehicle 200 approaching an obstacle in the form of a kerb 300. The sensor 104 captures a series of images as the vehicle 200 moves forwards towards the kerb 300. Based on the captured images, the position signal 106 is sent to the control system 100 for processing. As described above, the position signal 106 can comprise image data, and / or further information based on processing of such image data. For example, the position signal 106 can include a two- or three-dimensional model or map based on the images, and / or can include raw or processed image data that can be processed by the control system 100. In Figure 3, the kerb 300 is outside the field of view 212, and so the images captured by the sensor 104 do not include the kerb 300, As such, the position signal 106 is indicative of there not being a kerb near the driver’s side of the vehicle 200. Alternatively, no position signal is sent while there is no kerb near the driver’s side of the vehicle. As the vehicle 200 approaches the kerb 300, as shown in Figure 4, the field of view 212 begins to capture images of the kerb 300. The kerb (or kerb-like object) is identified as such, and the position signal 106 changes to become indicative of there being a kerb (or kerb-like object). Any combination of characteristics of the feature(s) identified within the images captured by the sensor 104 can be used to determine whether the vehicle 200 is near a kerb (or kerb-like object) such as the kerb 300. Optionally, one or more characteristics of an identified step can be further analysed to determine whether it is a kerb. For example, the step may not be considered a kerb if it is higher than a first height threshold, since it may not be desirable to allow the vehicle 202 to approach such a step too closely and / or to drive onto it. The first height threshold can at least partly be based on a diameter of one or all of the wheels of the vehicle, and / or a height of one or more features of the vehicle, such as a region of the vehicle’s body. As another example, the step may not be considered a kerb if it is lower than a second height threshold, since it may be desirable to allow the vehicle to approach such a low step at any angle, rather than at only the limited range of angles as described below. As another example, the step may only be considered a kerb if it makes a maximum angle with the horizontal (or with the adjacent surface, such as the road surface) that is above an angle threshold. For example, the angle threshold may be 35° to the horizontal (or the adjacent surface). If the step rises at a higher angle than that, it can be considered a kerb. If the step is at a lower angle than that, it may be considered a ramp that the vehicle can drive up at any angle, or at a different angle than if a steeper kerb is identified. As another example, the step may be considered a kerb based at least in part on its location relative to the vehicle’s location. For example, the control system 100 can use information about the vehicle’s location to determine whether it is expected that a kerb will be located within the current field of view. For example, a kerb can be expected at the edge of a road adjacent to where the vehicle is currently located, but may not be expected in the middle of a road or in an offroad location. The vehicle’s location can be determined using, e.g., GPS, radio signals from one or more wireless telecommunications systems, or any other suitable source. Alternatively, or in addition, vehicle 200 can display information to a user / driver of vehicle 200 via a user interface, responsive to which the user / driver can input information confirming or rejecting identification of an object. For example, the user interface can include the display 110, which can display the object and provide an indication that it has been identified as a potential kerb, along with a request for the user / driver to confirm or reject the indication. The display 110 can form part of the infotainment system 108 as shown in Figure 2, or can be a separate display. The display 110 can provide, for example, a top-down and / or a perspective view of the object, optionally also showing surrounding elements such as other cars, roadside markings, signs, other obstacles, etc. The view(s) can be schematic or based on imagery or other data captured by sensors, optionally including sensor 104. The view(s) can also combine imagery and other data with overlaid information. For example, an object identified as a potential kerb can be displayed as, for example, a two- or three-dimensional model or other representation overlaying a representation of the area surrounding the vehicle 200. The indication that the object has been identified as a kerb can be displayed on display 110, for example using a text description. Optionally, other forms of visual indicia can be used to indicate that the object has been identified as a kerb. For example, the object can be outlined in a contrasting colour, coloured, patterned, and / or animated, so as to distinguish it from other objects and / or make it stand out on the display. Alternatively, or in addition, the user interface can include an audio system, such as the audio system 112 of the infotainment system 108. In that case, the indication that the object has been identified as a kerb can take the form of an audible indicator that is output through the audio system 112. For example, a sound can be played to the user / driver. Alternatively, or in addition, the indication can involve speech output via the audio system 112. Optionally, the user / driver’s confirmation or rejection of the identification of the object as a kerb can be input via the user interface. For example, if the display 110 is a touchscreen, the user / driver’s confirmation or rejection can be input by manual interaction with the display 110. As an example, the object can be identified as potentially being kerb, and the options “Yes" and “No” can be provided as buttons on the touchscreen. Alternatively, or in addition, the user interface can include a microphone (not shown), and the user / driver’s confirmation or rejection of the identification of the object as a kerb can be provided verbally by the user / driver. Alternatively, or in addition, the user / driver’s confirmation or rejection of the identification of the object as a kerb can be input via a steering wheel (not shown). For example, the user / driver can move the steering wheel in a manner that indicates confirmation or rejection. As well as identifying whether the obstacle is of a certain type (such as a kerb, for example), the position signal 106 is indicative of the vehicle’s position relative to the obstacle. Again, the position signal 106 can include information in the form of a two- or three-dimensional model or map of the obstacle relative to the vehicle 200, or can include information indicative of the image data captured by the sensor 104, for processing by the control system 100. Once the obstacle has been identified as a kerb (or kerb-like object), the control system 100 determines, in dependence on the position signal 106: a first path that will cause the road wheels of the vehicle to avoid the obstacle; and a second path that will cause at least a first road wheel of the vehicle to encounter the obstacle at or above a minimum predefined approach angle. The potential interactions of the front wheel 202 with the kerb 300 will now be described with reference to Figures 5 to 7, to provide context for the description of the first and second paths. Figures 5 to 7 show the passenger-side front wheel 202 in contact with the kerb 300. Figure 5 is a view looking from the front of the car along the kerb 300, showing the front wheel 202 turned into the kerb 300. Only the wheel 202 is shown - the rest of the vehicle is omitted for clarity. Figure 6 and 7 are plan views, showing a minimum predefined approach angle in the form of a first angle 302. First angle 302 represents the minimum acceptable angle that the wheel 202 can make with the kerb 300 and still safely drive up onto the kerb 300. If the wheel 202 makes contact with the kerb 300 at an angle that is less than angle 302 and the vehicle continues forward in an attempt to cause the wheel 202 to mount the kerb, there is a risk of damage, including tyre scrub against the kerb and / or damage to the wheel itself from rubbing on the kerb 300. At least part of the risk is that an attempt to cause the front wheel 202 to mount the kerb 300 at less than angle 302 may not be successful, causing the front wheel 202 to slip off the kerb, potentially causing damage such as that described above. In Figure 6, the approach angle 304 of the front wheel 202 is greater than the first angle 302, and so vehicle 200 can drive forward such that the front wheel 202 mounts the kerb 300 with minimal risk of damage to the tyre or the wheel itself. In Figure 7, the approach angle 306 of the front wheel 202 is less than the first angle 302. This means that, if the vehicle 200 drives forward, there is a risk of damage to the tyre or the wheel itself, especially if the angle causes the front wheel 202 to slip off the kerb. As shown in Figure 8, at a low enough approach angle 308, the front wheel 202 will either not contact the kerb 300, or will do so at a sufficiently oblique angle that the wheel 202 is not unduly at risk of serious damage. The first and second paths mentioned above will now be described with reference to Figure 9, which shows the vehicle 200 approaching the kerb 300. Once the kerb 300 has been identified as such and the position signal 106 determined, the control system 100 calculates a first path 310 and a second path 312 in dependence on the position signal 106. If the vehicle 200 moves forward such that the front wheel 202 follows the first path 310, the front wheel 202 will avoid the kerb 300. In this context, “avoid” means that the front wheel 202 will not touch the kerb 300, or will encounter the kerb 300 at an angle sufficiently low that the risk of damage is avoided or minimised. If the vehicle 200 moves forward such that the front wheel 202 follows the second path 312, the front wheel will encounter the kerb 300 at the minimum predefined approach angle (i.e., first angle 302). Where the front wheel 202 is a distance from the kerb 300, calculation of the first path 310 and the second path 312 may take into account the effect of steering on the vehicle 200. For example, as the vehicle 200 moves forward with the wheel 202 at a non-zero angle, the angle that the vehicle 200 itself makes with the kerb 300 will change. For example, Figure 10 shows the vehicle 200 at a first position 314 and a second position 316 along a path 318. The front wheels 202 and 204 are orientated straight forward, meaning that the path does not change as the vehicle 200 moves forwards from the first position 314 to the second position 316. In contrast, Figure 11 shows the vehicle 200 at the first position 314 and the second position 316 along the path 318. In Figure 11, the front wheels 202 and 204 are steered to the left. As the vehicle 200 moves forward from the first position 314, the angle of the front wheels 202 and 204 causes the front of the vehicle 200 to move leftwards. The net result of this movement is that vehicle 200 rotates, in plan, counter-clockwise as it moves forward. The approach angle of the front wheel 202 relative to the kerb 300 therefore varies as the vehicle moves along the path. The mapping of steering angles to vehicle and wheel paths is well understood, and so will not be described in detail. Depending upon the angle of the vehicle 200 relative to the kerb 300, the first path 310 and / or the second path 312 may need to take into account restrictions placed on the steering due to the vehicle’s steering lock. Having determined the first path 310 and the second path 312, the control system 100 outputs a steering control signal and / or an instruction signal. A steering control signal, such as the steering control signal 116 in Figure 2, can be output in the event the vehicle 200 is capable of controlling steering of the front wheels 202 and 204. In that case, the vehicle 200 will include a steering system, such as steering system 118 shown in dashed lines in Figure 2. The steering system 118 includes the components necessary for controlling the steering angle of the front wheels 202 and 204. The steering system 118 receives the steering control signal 116 and uses it as a basis for controlling the steering angle of the front wheels 202 and 204, such that the vehicle 200 follows a trajectory either in dependence on the first path 310 so as cause the front wheel 202 to avoid the kerb 300, or in dependence on the second path 312 so that the front wheel 202 encounters the kerb 300 at or above the minimum predefined approach angle 302. The steering system 118 can form part of a more general autonomous or semi-autonomous vehicle controller (not shown) that is able to control other car systems, such as brakes, accelerator, indicators, etc. Optionally, rather than completely controlling the vehicle’s steering, the steering system 118 can apply a torque through the steering system in order to encourage the user / driver to steer in a particular direction and / or manner. In this way, the user / driver can still elect to steer in a direction other than that suggested by the control system 100, but will understand from torque fed back through the wheel that certain steering directions are discouraged. Alternatively, or in addition, an instruction signal, such as instruction signal 120 in Figure 2, can be output to cause the user / driverto be instructed to control the steering angle of the front wheels 202 and 204, such that the vehicle 200 follows a trajectory either in dependence on the first path 310 so as to cause the front wheel 202 to avoid the kerb 300, or in dependence on the second path 312 so that the front wheel encounters the kerb 300 at or above the minimum predefined approach angle 302. The instruction signal 120 is shown in Figure 2 as being directed to the infotainment system 108. The instruction signal 120 can cause the infotainment system 108 to display an instruction to the user / driver of vehicle 200. The instruction signal 120 can include details of the information to be displayed for the instruction. For example, the instruction signal 120 can include information such as text, audio, and / or graphical information for display by the display 110 and / or reproduction via the audio system 112. Alternatively, or in addition, the instruction signal 120 can include information that the infotainment system 108 can use as the basis for the generation of such text, audio, and / or graphical information for display by the display 110 and / or reproduction via the audio system 112. Figures 12 to 16 show a sequence of images 214 showing what is displayed on the display 110 in one implementation. Prior to the sequence commencing at Figure 12, display 110 can show any suitable information, including information about the vehicle, a map, images from one or more cameras mounted to the car (including camera 104), entertainment information, etc. As the vehicle 200 approaches the kerb 300, the control system 100 receives the position signal 106 from the camera 104. As explained above, the position signal 106 can include information identifying the kerb 300 and its position relative to the vehicle 200, or can include data based on one or more images captured by the camera 104, for processing by the control system 100. Based on the position signal 106, the control system 100 identifies the kerb 300 and displays it on the display 110 as shown in Figure 12. A vehicle icon 320 representing the vehicle 200 is also shown. The kerb 300 is highlighted such that the user / driver can tell it is an object that the vehicle 200 should either avoid (e.g., the park next to) or mount at a suitable angle. Although not shown, the display 110 can also show additional information and / or instructions. For example, the word “kerb” or similar can be displayed on or adjace nt to the kerb 300. An instruction such as “move forward slowly” can also be shown to the user / driver. Some or all of such additional information and / or instructions can also be reproduced as speech by audio system 112. As the vehicle 200 moves forward, the display 110 is updated to take into account relative movement between the vehicle 200 and the kerb 300. For example, in Figure 13 (and Figure 14, which shows a detail from Figure 13), the vehicle 200 has moved closer to the kerb 300 relative to what is shown in Figure 12. At this stage, the control system 100 calculates the first path 310 and second path 312, for example as described above, and forwards information to the display 110 allowing for the first path 310 and the second path 312 to be displayed as shown in Figures 13 and 14. The first path 310 and the second path 312 can be shown as lines extending from the respective front wheels 202 and 204 of the vehicle 200. The lines represent an instruction to the user / driver to control the steering angle of the front wheels 202 and 204, such that the vehicle 200 follows a trajectory either in dependence on the first path 310 so as to cause the front wheel 202 to avoid the kerb 300, or in dependence on the second path so that at least one road wheel of the vehicle encounters the obstacle at or above the minimum predefined approach angle. In the implementation shown in Figures 13 and 14, a region 322 between the first path 310, the second path 312, and the kerb 300 is hashed and marked with warning indicia in the form of an exclamation mark 350, letting the user / driver know that the vehicle 200 should not be steered into the region 322. The warning indicia can include, for example, bright hashing, a warning colour such as red, yellow, or orange, a flashing texture, colour or pattern, or the like, filling and / or surrounding the region 322. The indicia can also include explanatory text and / or symbols (e.g., exclamation mark 350) indicating the importance of the region 222. The provision of the warning indicia can also represent an instruction to the user / driver to control the steering angle of the front wheels 202 and 204, so as to steer out of or away from the region 322. The user / driver can choose whether the intention is avoid the kerb 300 or to mount the kerb 300. If the intention is to avoid the kerb 300, then the user / driver steers the front wheels 202 and 204 such that the front wheel 202 remains on or to the road-side side of the first path 310. That is, the vehicle 200 follows a trajectory in dependence on the first path 310 so as to cause the front wheel 202 to avoid the kerb 300. Figure 15 shows an example in which the user / driver decided to avoid the kerb 300. The front wheels 202 and 204 were steered to the right, and the front wheel 202 followed the first dotted line 324 shown in Figures 13 and 14 (line 324 is shown in Figure 15 for illustration purposes, and may not necessarily be shown to the user / driver in practice). It will be noted that the first dotted line 324 is offset from the first path 310 along at least some of its length in Figure 14, showing that the first path 310 need not necessarily be followed exactly. If the intention is to mount the kerb 300, then the user / driver steers the front wheels 202 and 204 such that the front wheel 202 remains on or to the kerb-side side of the second path 312. That is, the vehicle 200 follows a trajectory in dependence on the second path 312 so that the front wheel encounters the kerb 300 at or above the minimum predefined approach angle 302, allowing the kerb 300 to safely be mounted. Figure 16 shows an example in which the user / driver decided to mount the kerb 300. The front wheels 202 and 204 were steered to the left, and the front wheel 202 followed the second dotted line 326 shown in Figures 13 and 14 (line 326 is shown in Figure 16 for illustration purposes, and may not necessarily be shown to the user / driver in practice). It will be noted that the second dotted line 326 is offset from the second path 312 along at least some of its length in Figure 14, showing that the first path 312 need not necessarily be followed exactly. The instruction signal 120 can be indicative of the predicted path of at least one of the front wheels 202, 204 or the rear wheels 206, 208 of the vehicle 200. The predicted path can be, for example, determined based on a steering signal indicative of a steering angle of the at least one steerable road wheel of the vehicle 200. For example, to assist the user / driver, the display 110 can show a predicted path representing the path that the front wheel 202 will take if the current steering angle is maintained. In Figures 13 and 14, for example, the steering signal is indicative of a predicted path 332 based on the front wheel 202 being turned slightly to the left of straight ahead. The predicted path 332 of the front wheel 202 based on the current angle of the front wheels 202 and 202 is displayed, allowing the user / driver to determine whether the current steering angle will result in them avoiding or mounting the kerb 300, depending upon their intentions and choice of steering path. In Figures 15 and 16, the path taken by the front wheel 202 (shown by first dotted line 324 and second dotted line 326) avoided the region 322. It will be appreciated, however, that where the vehicle 200 is far enough from the kerb 300, it is possible for the front wheel 202 to temporarily enter the region 322 and then steer out again in order to avoid the kerb 300 or mount it at the minimum approach angle 302. For example, Figure 17 shows an example where the vehicle 200 is a relatively long distance from the kerb 300. At this distance, the vehicle 200 could begin at virtually any angle facing the kerb 300, move forward by at least some distance with the front wheels steered at any sequence of angles over time, and still successfully be steered so as to follow a trajectory in dependence on the first path 310 or the second path 312. For example, following the path 328 still results in the kerb 300 being avoided, and following path 330 still results in the kerb being mounted at the minimum approach angle 302. To reduce driver confusion, control system 100 can be configured to only initially present the first path 310 and the second path 312 when the vehicle 200 is within a predetermined range of the kerb 300. A shorter range reduces the complexity of the possible paths that the user / driver may steer as the vehicle 200 approaches the kerb 300. Accordingly, the control system 100 can be configured to determine a distance to the identified object (e.g., the kerb) and to modify the instruction signal at least partly based on the distance. For example, modifying the instruction signal can comprise suppressing the instruction signal until the distance falls below a threshold. The steering control signal and / or the instruction signal can be indicative of a relationship between the predicted path, and the first and second paths. For example, where the car is autonomous or semi-autonomous, the steering control signal can represent an error term, representing a difference between the current angle of the front wheels 202, 204 and an angle that will result in the vehicle 200 following a trajectory either in dependence on the first path 310 so as cause the front wheel 202 to avoid the kerb 300, or in dependence on the second path 312 so that the front wheel 202 encounters the kerb 300 at or above the minimum predefined approach angle 302. The user / driver may be requested to provide an instruction indicating whether the user / driver prefers the vehicle to follow a trajectory in dependence on the first path 310 or the second path 312. For example, as shown in Figure 18, the display 110 can present a user / driver with first button 334 located adjacent to the first path 310, and a second button 336 located adjacent to the second path 312, The user / driver can select the first button 334 to avoid the kerb 300 (in effect, to parallel park) and the second button 336 to cause at least the front wheel 202 to mount the kerb 300. In other implementations, instead of buttons, a static image, and / or an animation or graphic of the vehicle mounting the kerb and / or parked parallel to the kerb 300 can be displayed, the user / driver being able to choose by manually interacting with the desired option via the display 110. The request to the user / driver to choose whether to avoid or mount the kerb 300 can be presented in any other suitable manner, including audible (e.g., speech or other sounds replayed via the audio system 112 or another audio reproduction system), visible (e.g., icons, animations, buttons, or other interface elements on the display 110 or another visual output device), or haptic (e.g., vibrations or other tactile feedback via the steering wheel, seat, floor, control interface component such as an accelerator or brake pedal, and / or any other component of the vehicle 200), for example. The user / driver’s instruction in response to the request to choose whether to avoid or mount the kerb 300 can take any suitable form. For example, the user / driver can press one of the buttons 334, 336 described above. The instruction can be made via any other input interface. For example, the user / driver can effectively instruct whether to avoid or mount the kerb by steering with the steering wheel in the desired direction. Speech recognition can be used to interpret verbal instructions from the user / driver. The user / driver’s interaction with the display 110 can be interpreted as an instruction. For example, if the user / driver selects the high part of the kerb 300 displayed on display 110, the control system 100 can interpret the user / driver’s instruction as being to cause the front wheel 202 to mount the kerb 300. If the user / driver selects the road surface beside the kerb 300 in front of the image of the vehicle 200, the control system 100 can interpret the user / driver’s instruction as being to cause the front wheel 202 to avoid the kerb 300. Optionally, the control system can be configured detect inputs via the steering wheel and to infer from them the user / driver’s intention as regards whether to avoid or mount the kerb 300. If the vehicle is equipped to allow assisted, autonomous, or semi-autonomous control of the steering angle, the control system 100 can be configured to output a steering control signal to assist in changing the angle to ensure that the appropriate trajectory is met. For example, where it is inferred from a change in steering angle that the user / driver’s intention is the mount the kerb, the steering control signal can cause assisted turning of the front wheel 202 in the direction to ensure that the minimum approach angle is met before the front wheel 202 reaches the kerb 300. However the user / driver’s intention is inferred, the control system 100 can update the displayed image to remove the first or second path associated with the option that was not selected. The user / driver is therefore presented with clearer instructions, directed only to the option they have chosen. The steering control signal and / or the instruction signal can be indicative of a steering adjustment to be made to the steering angle, such that the vehicle 200 follows a trajectory in dependence on the first path 310 or the second path 312 (e.g., the trajectory selected by the user / driver). For example, if the car is autonomous or semi-autonomous, the steering control signal can include the error term described above. If the user / driver is driving, the instruction signal can communicate to the user / driver how they should steer the vehicle. For example, as shown in Figures 19 and 20, the display 110 can display the first path 310, the second path 312, and the predicted path 332 (as were shown in Figures 13 and 14). In Figure 19, the user / driver has indicated (explicitly via an interface, or implicitly by their steering inputs, for example) that they intend to avoid the kerb 300. The second path 312 has therefore been removed, and only the first path 310 and the predicted path 332 remain. The region 322 is (optionally) also still displayed, as a warning to the user / driver not to drive into it. Figure 19 shows an instruction signal in the form of an arrow 338 on the display 110, instructing the user / driver to steer more to the right. The arrow 338 can flash, be animated, and / or be a bright colour, texture, or pattern, for example, so that it stands out. In Figure 20, the user / driver has indicated (explicitly via an interface, or implicitly by their steering inputs, for example) that they intend to mount the kerb 300. The first path has therefore been removed, and only the second path 312 and the predicted path 332 remain. The region 322 is (optionally) also still displayed, as a warning to the user / driver not to drive into it. Figure 20 shows an instruction signal in the form of an arrow 340 on the display 110, instructing the user / driver to steer more to the left. The arrow 340 can flash, be animated, and / or be a bright colour, texture, or pattern so that it stands out. Any other suitable form of instruction signal can be used to communicate to the user / driver how they should steer the vehicle. For example, the instruction signal can be audible (e.g., speech or other sounds replayed via the audio system 112 or another audio reproduction system), visible (e.g., icons, animations, buttons, or other interface elements on the display 110 or another visual output device), or haptic (e.g., vibrations or other tactile feedback via the steering wheel, seat, floor, control interface component such as an accelerator or brake pedal, and / or any other component of the vehicle 200), for example. The instruction signal can optionally communicate an amount of steering input in any suitable way. For example, where an arrow is displayed, the arrow’s length, size, movement, colour, animation, or any other visible information can be used to communicate the amount of steering input required. Other forms of communication, including visible, audible and haptic, can also be used to communication the amount of steering input required. For example, a graphic or an animation of the steering wheel can be displayed, demonstrating to the user / driver what steering inputs are required. The control system 100 can be configured to update the first path 310 and / or the second path 312 based at least partly on changes to the position signal 106 as the vehicle moves relative to the obstacle. For example, sensor 104 can capture a sequence of images or video and use that to update the position of the kerb 300 as the vehicle 200 moves relative to it. This can in turn be used to update the information presented on the display 110. The control system 100 can be configured to determine whether the vehicle 200 is capable of steering along either or both of the first and second paths based on the vehicle’s position. For example, the control system 100 can use the current position and orientation of the vehicle 200, and information regarding the available trajectories based on the possible steering angles, in order to determine whether it is possible for the front wheel 202 to avoid the kerb 300, and / or whether it is possible for the front wheel 202 to come into contact with the kerb 300 at an approach angle at or above the minimum approach angle. The steering control signal and / or the instruction signal can be indicative of that determination. For example, in the Figure 21, the vehicle 200 is close to the kerb 300, and facing it almost directly. The dotted line 342 shows the path that would be taken by the front wheel 202 on full right lock. It can be seen that even on full right lock, the front wheel 202 will not avoid the kerb 300 as the vehicle moves forward. This can be communicated to the user / driver in any suitable way. For example, a path such as line 342 can be shown terminating at an ‘X’ or a line, or can be indicated with an indicator such as the ‘X’ icon 360 shown in Figure 21, to indicate that the path is not acceptable (due to a risk of wheel and / or other damage). Alternatively, the line 342 can be shown in a different size, colour, pattern, or animation, etc, in order to show that the path it represents is not available. Alternatively, or in addition, the unavailability of the path can be communicated using any other form of communication, including visible, audible and haptic communication. Alternatively, the unavailability of the path can be indicated by its absence on the display. In another example, in Figure 22, the vehicle is quite close to the kerb 300 and almost parallel to it. The dotted line 344 shows the path that would be taken by the front wheel 202 on full left lock. It can be seen that even on full left lock, the front wheel 202 will approach the kerb 300 at less than the minimum approach angle as the vehicle moves forward. This can be communicated to the user / driver in any suitable way. For example, a path such as line 344 can be shown terminating at an ‘X’ or a line, or can be indicated with an indicator such as the ‘X’ icon 360 shown in Figure 21, to indicate that the path is not acceptable (due to a risk of wheel and / or other damage). Alternatively, the line 344 can be shown in a different size, colour, pattern, or animation, etc, in order to show that the path it represents is not available. Alternatively, or in addition, the unavailability of the path can be communicated using any other form of communication, including audible (e.g., speech or other sounds replayed via the audio system 112 or another audio reproduction system), visible (e.g., text, icons, animations, or other interface elements on the display 110 or another visual output device), or haptic (e.g., vibrations or other tactile feedback via the steering wheel, seat, floor, control interface component such as an accelerator or brake pedal, and / or any other component of the vehicle 200). Alternatively, the unavailability of the path can be indicated by its absence on the display. The steering control signal and / or the instruction signal can optionally be indicative of the steering angle of the steerable wheel(s) of the vehicle. This can include, for example, visible, audible and / or haptic communication of the steering angle. As one example, the display 110 can show an visual indication of the steering angle. This can include a visual representation of the current steering angle of steerable wheel(s) using arrows 352, as shown in Figure 23 for front wheels 202, 204, or any other suitable representation. The steering control signal and / or the instruction signal can optionally be indicative of the first path 310 and / or the second path 312, As shown in Figure 24, the steering control signal and / or the instruction signal can also optionally be indicative of a first region 346 at least partly bounded by the first path, a second region 348 at least partly bounded by the second path 312, and / or a third region (such as region 322) at least partly bounded by the first region 346 and the second region 348. Any or all of the regions can also be partly bounded by the kerb 300. The display of one or more such regions can provide an alternative way of instructing the user / driver. For example, if the user / driver is to mount the kerb 300, they can be instructed to steer away from the first region 346 and the region 332. If the user / driver is to avoid the kerb 300, they can be instructed to steer away from the second region 348 and the region 332. The regions can optionally be combined. For example, the first region 346 and the region 332 can be presented as a single combined region that the user / driver is instructed to avoid when the intention is to mount the kerb 300. Similarly, the second region 348 and the region 332 can be presented as a single combined region that the user / driver is instructed to avoid when the intention is to avoid the kerb 300. The steering control signal and / or the instruction signal can optionally be indicative of one or more correction inputs to apply to the steering angle to ensure that at least one road wheel of the vehicle avoids the obstacle and / or encounters the obstacle at or above the minimum approach angle. Optionally, the control system is configured to: receive a speed signal indicative of a speed of the vehicle; and determine the steering control signal and / or the instruction signal at least partly in dependence on the speed signal. The speed signal can be supplied from any suitable vehicle system, using, for example, GPS and / or one or more sensors for determining a rotation speed of one more drivetrain components. For example, the control system 100 can operate such that the steering control signal and / or the instruction signal are only output if the speed signal is indicative of the vehicle’s speed being below a threshold. This helps avoid the user / driver being interrupted by the steering control signal and / or the instruction signal during ordinary driving conditions where it is not intended to drive the vehicle close to the kerb, or to cause the vehicle to mount the kerb. Alternatively, or in addition, the steering control signal and / or the instruction signal can vary based different speeds applying to the first and second paths. For example, it may be acceptable to avoid the kerb at a higher speed than a speed at which it is acceptable to mount the kerb. Referring to Figure 29, there is shown a plan view of the vehicle 200 approaching the kerb 300. In this case, the second path 312 is calculated as a straight line extending from the front wheel 202 to the kerb, at the minimum approach angle. Also shown are a right lock line 362 corresponding with the maximum possible right turn, and a left lock line 364 corresponding with the maximum possible left turn. If the user / driver (or the vehicle itself, if it is steering autonomously or semi-autonomously) steers so as to keep the angle of the front wheels between the second path 312 and the left lock line 364, the front wheel 202 will be sure the engage the kerb 300 at or above the minimum approach angle. Of course, if the vehicle is steered too far to the left too early, it is possible that the approach angle will overshoot to the left. This can be prevented by displaying another line (or otherwise indicating to the user / driver) showing the maximum amount by which the front wheel 202 can turn to the left and still meet the approach angle requirements. It will be understood that the user / driver (or the vehicle itself, if it is steering autonomously or semi-autonomously) can potentially steer to the right of the second path 312 for some time while still being able to steer back to, or to the left of, the second path 312 in time for the front wheel 202 to engage the kerb at or above the minimum approach angle. The horizontal line 366 represents a point by which, forthe current vehicle approach angle, the front wheel 202 must be steered back towards the second path to ensure the minimum approach angle will be achieved before the front wheel 202 engages the kerb 300. The line 366 can optionally be displayed on the display 110, and updated if necessary as the vehicle 200 moves closer to the kerb 300. An audible, visual, and / or haptic warning can be provided by way of, for example, the infotainment system 108, or any other vehicle system. A further horizontal line 368 represents a point at which the vehicle’s speed will be assessed, and if necessary, a warning or vehicle control signal output. The line 368 can optionally be displayed on the display 110, and updated if necessary as the vehicle 200 moves closer to the kerb 300. The warning can be an audible, visible, and / or haptic warning output to warn the user / driver that the vehicle is approaching the kerb too fast. The user / driver can heed the warning and reduce the vehicle’s speed by braking or reducing the throttle. If the warning is not heeded in time, and the vehicle 200 is suitably equipped, the vehicle 200 can act to automatically slow and / or stop itself to avoid damage that might be caused by hitting the kerb 300 at too high a speed. If the vehicle is being operated autonomously orsemi-autonomously, a vehicle control signal can be output, in response to which the vehicle 200 can autonomously or semi-autonomously reduce its speed, for example by braking. The lines 366 and 368 can be calculated in any suitable way. For example, they can use the same sensor (such as sensor 104) that is used to generate the position signal 106. Alternatively, or in addition, one or more additional sensors can be used. For example, a lidar sensor (not shown) positioned at the front of the vehicle may have a greater range and / or offer better distance estimation precision in the forward direction than the mirror-mounted camera, allowing more notice and / or more accurate prediction of location and speed. Either of the horizontal lines 366 and 368 can be closer to the kerb depending upon the implementation, and they can optionally be the same distance from the kerb. In addition, there can be a different line 366 and / or 368 for each of the first path 310 and the second path 312. That is, the braking point may be different for the first path 310 and the second path 312, and the point at which the wheel must start being turned to ensure the kerb is avoided or mounted at the minimum approach angle can also be different for the first path 310 and the second path 312. The control system can be configured to determine that the at least one road wheel of the vehicle will encounter the obstacle at less than the minimum approach angle. In dependence on that determination, the control system can output a warning signal or a braking signal. The warning signal can be an instruction to the user / driver to slow or stop the vehicle 200 before the at least one road wheel encounters the obstacle. The braking signal can cause the brakes of the vehicle to autonomously or semi-autonomously slow and / or stop the vehicle before the at least one road wheel encounters the obstacle. For example, in the scenario shown in Figure 22, it is apparent that the front wheel 202 cannot be turned to the left sufficiently to meet the kerb 300 at or above the minimum approach angle. Upon determining that the vehicle is moving along the path 344, the control system 100 causes a warning signal to be output. The warning signal can take any suitable form, including audible (e.g., speech or other sounds replayed via the audio system 112 or another audio reproduction system), visible (e.g., text, icons, animations, or other interface elements on the display 110 or another visual output device), or haptic (e.g., vibrations or other tactile feedback via the steering wheel, seat, floor, control interface component such as an accelerator or brake pedal, and / or any other component of the vehicle 200), for example. Optionally, if the user / driver does not brake in response to the warning signal, or does not brake sufficiently, and the vehicle 200 has the required functionality, the control system 100 can output a braking signal to cause the brakes to be applied autonomously. Alternatively, or in addition, if it is determined that the wheel for which the first and second paths has been determined cannot avoid contact with the kerb (due to the wheel location and angle, and / or the speed of the vehicle), the control system 100 can be configured to turn the wheel towards the kerb so that the tyre of the wheel contacts the kerb first, thereby avoiding damage. There can be a speed limit beyond which this is not done, and the control system 100 may take into account other factors such as obstacles on or near the kerb. Although the examples above focus on the path of the steerable front wheel 202, it will be appreciated that the same principles can be applied to any of the other wheels 204, 206 or 208. For example, the principles described above can be applied to the passenger side rear wheel 206. Figure 25 shows the display 110 with the first and second paths 310,312 shown for the passenger side rear wheel 206. Since the rear wheels 206, 208 are not steerable, the predicted path 332 of the rear wheel 206 is dependent on the steering angle of the front wheels 202, 204. Optionally, the principles above can be applied to any combination of the wheels 202, 204, 206, 208. For example, both passenger side wheels 202, 206 can have respective first and second paths determined for them. Figure 26 shows the display 110 with the first and second paths 310, 312 shown for the passenger side front wheel 202, and first and second paths 410, 412 shown for the passenger side rear wheel 206. The predicted path 332 of the front wheel 202 and a predicted path 432 of the rear wheel 206 are also shown. Any combination of two, three, or four (or more, if the vehicle has more wheels) can have first and second paths, and optionally the predicted paths, calculated (and optionally displayed) forthem. While the examples illustrated to date have assumed forward movement of the vehicle 200, the same principles can be applied when the vehicle 200 is reversing. For example, Figure 27 shows vehicle 200 reversing, with the first path 310, second path 312, and the predicted path 332 shown extending in the rearward direction. The direction in which the paths are calculated and used to generate an instruction and / or a steering control signal can be selectable by the user / driver, and / or can automatically be selected based on the currently selected drive direction (i.e., forward or reverse). The first path 310, the second path 312, and optionally the predicted path 332, 432 can also be displayed for any combination of any one or more of the wheels 202, 204, 206, 208. For example, Figure 28 shows the first path 310 and the second path 312 for the passenger side front wheel 202, and the first path 410 and second path 412 for the driver’s side front wheel 204. It should be noted that the paths for the different wheels do not, in this implementation, represent paths that will simultaneously be taken by both of the front wheels 202, 204. Rather, the user / driver can choose between the first path 310 for the front wheel 202, the second path 312 for the front wheel 202, the first path 410 for the front wheel 204, and the second path 412 for the front wheel 204. If, say, the second path 312 for the front wheel is selected, then the first path 310, the first path 410, and the second path 412 are no longer relevant. In other implementations where a path is presented for more than one wheel, the paths for some or all of those wheels can be calculated together for a single trajectory of the vehicle. That is: a first path is determined for each wheel, and a single set of first paths selected such that all of the wheels will avoid the kerb 300, and a second path is determined for each wheel, and a single set of second paths selected such that all of the wheels will mount the kerb at or above the minimum approach angle. A similar approach can be taken for a subset of the wheels. For example, both kerb-side wheels, or both front wheels (typically, but not necessarily, when the vehicle is moving forward), or both rear wheels (typically, but not necessarily, when the vehicle is reversing). In a vehicle that is capable of only being manually steered under the control of a driver, the control system 100 can be configured to only output the instruction signal. In a vehicle that is capable of only autonomous steering without user intervention at least in one or more driving modes, the control system 100 can be configured to only output the steering control signal to an autonomous vehicle controller (not shown) that can control the steering (and optionally movement) of the vehicle. In a vehicle capable of both manual and autonomous or semi-autonomous steering, the control system can be configured to output the instruction signal and / or the steering control signal. Optionally, the user / driver can be offered the choice of whether the instruction signal and / or the steering control signal is output by the control system. In addition to taking into account obstacles such as kerb 300, the control system 100 can also be configured to take into account other elements of the environment. This can include, for example, other vehicles, other obstacles (e.g., obstacles that are not kerb-like due to, for example, their height, size, shape, etc), and indicia such as painted road markings and signs. Optionally, where the vehicle has active suspension that allows height adjustment, the control system can be configured to adjust a ride height of the vehicle to mitigate or avoid the possibility of damage to the vehicle’s underbody or bodywork, or other portions of the vehicle. For example, where it is intended to mount the kerb, the control system can be configured to raise the ride height at one or more of the wheels, to avoid underbody or bodywork scrapes due to contact with the kerb. In another example, where the kerb is particularly high or otherwise likely to interact with the underbody or bodywork of the car even when the wheels avoid the kerb, the height adjustment can be used to avoid underbody or bodywork scrapes due to contact with the kerb. In each case, the height adjustment can optionally be fixed (e.g., maximum height is always selected) or selected based on an assessment of the image or other data captured by the sensor, such as sensor 104. Turning to Figure 30, there is shown a schematic diagram of the vehicle 200, comprising a vehicle system 600. In this implementation, the vehicle system 600 comprises the control system 100, the sensor 104, the infotainment system 108, and the steering system 118. It will be appreciated that the vehicle system 600 can omit one or more of the infotainment system 108 and the steering system 118, depending upon whether the control system is configured to output the steering control signal 116 and / or the instruction signal 120. The control system 100 as illustrated in Figure 1 comprises one controller 102, although it will be appreciated that this is merely illustrative, and that the control system 100 can alternatively be distributed across two or more controllers, each of which has one or more processors and memory means. The controller 102 comprises processing means 610 and memory means 620. The processing means 610 may be one or more electronic processing devices 610 that operably execute computer-readable instructions. The memory means 620 may be one or more memory devices 620. The memory means 620 is electrically coupled to the processing means 610. The memory means 620 is configured to store instructions, and the processing means 610 is configured to access the memory means 620 and execute the instructions stored thereon. The controller 102 comprises an input means 630 and an output means 640. The input means 630 may comprise an electrical input 630 of the controller 102. The output means 640 may comprise an electrical output 640 of the controller 102. The input 630 is arranged to receive the position signal 106 from the camera 104. The position signal 106 is an electrical signal that indicative of the vehicle’s position relative to an obstacle such as a kerb. The output 640 is arranged to output one or more signals, including a steering control signal 116 and / or an instruction signal 120 as described herein. Turning to Figure 31, there is shown a method 500 according to an embodiment, for implementation within a vehicle, such as vehicle 200. The method 500 can be performed within a control system 100 comprising one more controllers 102, such as the control system 100 described in relation to Figure 27. In particular, the memory 620 may comprise computer-readable instructions that, when executed by the processing means 610 performs the method 500 according to an embodiment of the invention. The method 500 comprises receiving 502 a position signal at least partly based on data from a first sensor, such as camera 104. The position signal is indicative of the vehicle’s position relative to an obstacle, such as the kerb 300. The method 500 includes determining 504, in dependence on the position signal: a first path, such as first path 310, that will cause the road wheels of the vehicle to avoid the obstacle; and a second path, such as the second path 312, that will cause at least a first road wheel of the vehicle to encounter the obstacle at or above a minimum predefined approach angle. The method 500 includes outputting 506: a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as cause the road wheels of the vehicle to avoid the obstacle, or in dependence on the second path so that at least one road wheel of the vehicle encounters the obstacle at or above the minimum predefined approach angle; and / or an instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as to cause the road wheels of the vehicle to avoid the obstacle, or in dependence on the second path so that at least one road wheel of the vehicle encounters the obstacle at or above the minimum predefined approach angle. 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

1. A control system for a vehicle, the control system comprising one or more processors collectively configured to:receive a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle;determine, in dependence on the position signal:a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; anda second path that will cause at least the first road wheel(s) to encounter the obstacle at or above a minimum predefined approach angle; andoutput:a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle; and / oran instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as to cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle.

2. The control system of claim 1, wherein the one or more processors are collectively configured to: receive a steering signal from a second sensor, the steering signal being indicative of the steering angle of the at least one steerable road wheel of the vehicle; anddetermine the steering control signal and / or the instruction signal in dependence on the steering signal, such that the steering control signal and / or the instruction signal is indicative of a predicted path of the first road wheel(s).

3. The control system of claim 2, wherein the steering control signal and / or the instruction signal is indicative of a relationship between the predicted path, and the first and second paths.

4. The control system of claim 2 or 3, wherein the steering control signal and / or the instruction signal is indicative of a steering adjustment to be made to the steering angle, such that the vehicle follows a trajectory in dependence on the first path or the second path.

5. The control system of any preceding claim, wherein the first path will cause a portion of the vehicle’s bodywork to avoid the obstacle.

6. The control system of any preceding claim, wherein the first road wheel(s) comprises at least one of the steerable road wheel(s)7. The control system of any preceding claim, wherein the one or more processors are collectively configured to update the first path and / or the second path based at least partly on changes to the position signal as the vehicle moves relative to the obstacle.

8. The control system of any preceding claim, wherein the one or more processors are collectively configured to determine whether the vehicle is capable of steering along either or both of the first and second paths based on the vehicle’s position, wherein the steering control signal and / or the instruction signal is indicative of that determination.

9. The control system of any preceding claim, wherein the steering control signal and / or the instruction signal is indicative of one of more of:the steering angle;the first path and / or a first region at least partly bounded by the first path;the second path and / or a second region at least partly bounded by the second path ;a third region at least partly bounded by the first and second paths;whether the steering angle will result in the first road wheel(s) avoiding the obstacle;whether the steering angle will result in the first road wheel(s) encountering the obstacle at or above the minimum approach angle; andone or more correction inputs to apply to the steering angle to ensure that at least one road wheel of the vehicle avoids the obstacle and / or encounters the obstacle at or above the minimum approach angle.

10. The control system of any preceding claim, wherein the one or more processors are collectively configured to:receive a speed signal indicative of a speed of the vehicle; anddetermine the steering control signal and / or the instruction signal at least partly in dependence on the speed signal.

11. The control system of claim 10, wherein the one or more processors are collectively configured to, based on the speed signal, only output the steering control signal and / or the instruction signal when the speed of the vehicle is below a threshold.

12. The control system of any preceding claim, wherein the one or more processors are collectively configured to receive user input from a user interface, the user input being indicative of whether the user wishes the road wheel to avoid the obstacle or to encounter the obstacle at or above a minimum approach angle , wherein the steering control signal and / or the instruction signal is indicative of an angle of the steerable road wheel(s) that will cause the road wheel(s) to avoid the obstacle or to encounter the obstacle at or above the minimum approach angle, based on the user input.13, The control system of any preceding claim, wherein the instruction signal comprises feedback information for providing a user with feedback regarding the relationship between at least the steering angle and the at least one of the first and second paths.

14. The control system of any preceding claim, wherein the one or more processors are collectively configured to:determine that the at least one road wheel of the vehicle will encounter the obstacle at less than the minimum approach angle; andin dependence on that determination, output:a warning signal to instruct a user to use the brakes of the vehicle to slow and / or stop the vehicle before the at least one road wheel encounters the obstacle; and / ora braking signal to cause brakes of the vehicle to slow and / or stop the vehicle before the at least one road wheel encounters the obstacle.

15. The control system of any preceding claim, wherein the data is indicative of at least one dimension and / or shape-based characteristic of the obstacle.

16. The control system of any preceding claim, wherein the position comprises one or more of: an angle of the vehicle, or of a component of the vehicle, relative to the obstacle; and a distance of the vehicle, or of a component of the vehicle, from the obstacle.

17. A vehicle system comprising the control system of any preceding claim.

18. The vehicle system of claim 17, comprising at least a first sensor for sensing an obstacle and outputting the position signal indicative of the vehicle’s position relative to the obstacle.19, A vehicle comprising the vehicle system of claim 17 or 18, or the control system of any one of claims 1 to 16.20, A method comprising:receiving a position signal at least partly based on data from a first sensor, the position signal being indicative of the vehicle’s position relative to an obstacle;determining, in dependence on the position signal:a first path that will cause at least a first road wheel of the vehicle to avoid the obstacle; anda second path that will cause at least the first road wheel(s) to encounter the obstacle at or above a minimum predefined approach angle; andoutputting:a steering control signal for controlling a steering angle of at least one steerable road wheel of the vehicle, such that the vehicle follows a trajectory either in dependence on the first path so as cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle; and / oran instruction signal for causing a user to be instructed to control the steering angle of at least one steerable road wheel of the vehicle , such that the vehicle follows a trajectory either in dependence on the first path so as to cause the first road wheel(s) to avoid the obstacle, or in dependence on the second path so that the first road wheel(s) encounters the obstacle at or above the minimum predefined approach angle.

21. Computer readable instructions that, when executed by a computer, are arranged to perform the method of claim 20.30

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