GB2582753A

GB2582753A - System and method for controlling a vehicle

Info

Publication number: GB2582753A
Application number: GB1904399.1A
Authority: GB
Inventors: Tomar Ashutosh
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2019-03-29
Filing date: 2019-03-29
Publication date: 2020-10-07
Also published as: GB201904399D0

Abstract

A system and a method of using an ultrasonic sensor to monitor a vehicle surroundings. The system comprises a sensor, having a substrate 202, wherein the substrate is a vehicle body or arranged for attachment to a vehicle body. The sensor including an array of ultrasonic elements comprising one or more electrically conductive pathways 104 deposited on the surface of the substrate. The system also comprises a controller, to generate and receive a signal from the array and determine a property of an object relative to the array of ultrasonic elements in dependence on the received signal. The ultrasonic array may include a piezoelectric film and the conductive pathways preferably form a digitated or interdigitated structure. The property determined is preferably either the location of a vehicle relative to the array or the topology of the ground in the sensors field of view.

Description

System and Method for Controlling a Vehicle

TECHNICAL FIELD

Aspects of the invention relate to a system for controlling a vehicle, to a vehicle, to a method for controlling a vehicle.

BACKGROUND

Autonomous vehicles typically comprise a number of sensors the output of which is used to determine direction and or speed of a vehicle. LIDAR is an example of one such sensor type. It is used to identify objects, and provide an output for determining a safe path for the vehicle. Such sensors are operable to detect objects over a large range of distances. Consequently, some systems may have limited resolution at close distances which may hinder accurate determination of a safe path for a vehicle, or may be unsuitable for guiding a vehicle over complex terrain, such as demanding off-road terrain.

It is an object of embodiments of the invention to at least mitigate one or more of the

problems of the prior art.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention may be understood with reference to the appended claims.

In an aspect, there is a system for a vehicle, the system comprising a sensor and a control system. The sensor comprises a substrate, which is a vehicle body member or the substrate is arranged for attachment to a vehicle body member; and an array of ultrasonic elements, wherein the array of ultrasonic elements comprises one or more electrically conductive pathways deposited on the surface of the substrate. The control system comprises one or more controllers, the control system configured to generate a signal to one or more ultrasonic elements of the array of ultrasonic elements; to receive a signal from one or more ultrasonic elements of the array of ultrasonic elements; and to determine a property of an object relative to the array of ultrasonic elements in dependence on the received signal.

The system can comprise arrays with large number of closely spaced ultrasonic elements. The system may provide very high resolution sensing of objects, and may also be operable to perform additional functions. This means other systems may be dispensed with, reducing the cost and complexity of a vehicle. The system also may have a high degree of redundancy compared to conventional systems. This means the system may continue to function if some of the ultrasonic elements become damaged.

In embodiments, the one or more controllers collectively comprise: at least one electronic processor having an electrical input for receiving a signal from the one or more ultrasonic elements of the array of ultrasonic elements and an electrical output for outputting a signal to the one or more ultrasonic elements of the array of ultrasonic elements; 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 generate a signal to be output to the one or more ultrasonic elements of the array of ultrasonic elements determine the property of an object relative to the array of ultrasonic elements in dependence on the received signal.

In embodiments, the array of ultrasonic elements may comprise at least one piezo electric film.

In embodiments, the one or more conductive pathways may comprise one or more contact elements in electrical contact with at least one piezoelectric film.

In embodiments, the contact elements may be in electrical contact with at least one piezoelectric film to form one or more ultrasonic elements of the array of ultrasonic elements.

In embodiments, the vehicle body member may be a vehicle bumper.

In embodiments, at least a portion of the conductive pathway may be arranged as a digitated structure on the substrate. This may provide an arrangement that further improves the spacing between elements. Reducing the spacing may further improve the number of elements that can be achieved per area of substrate.

In embodiments, at least two portions of the conductive pathway may be arranged as an interdigitated structure. This may provide an arrangement that further improves the spacing between elements.

In embodiments, the conductive pathway may comprise at least two portions separated by the piezo electric film. This may provide an arrangement that further improves the spacing between portions of conductive pathways and therefore, may improve the number of elements that can be achieved per area of substrate.

In embodiments, the array of ultrasonic elements may comprise at least 10, 50, 100, 200, 500 or 1000 elements.

In embodiments, the controller may be configured to generate different signals for two or more ultrasonic elements of the array of ultrasonic elements, wherein the signals differ by one or more of phase, amplitude, frequency, pulse length or pulse shape.

In embodiments, the controller may be configured to generate different signals for two or more ultrasonic elements of the array of ultrasonic elements, to change the direction of waves produced by the ultrasonic array.

In embodiments, the object may comprise a second vehicle. The second vehicle may be any vehicle ahead of the sensor. In embodiments, the determined property may comprise the location of the second vehicle relative to the sensor.

In embodiments, the object may comprise the ground. For example, where the sensor is mounted to the front of a vehicle, the sensor may determine a property of the ground ahead of the vehicle. In embodiments, the determined property may comprise the topography of the ground ahead of the sensor. For example, the sensor may sense the ground ahead of the sensor to determine the, elevation, angle, surface texture or any other features relating to spatial properties of the ground. In embodiments, the controller may analyse the topography of the ground to identify hazards, optimal conditions or an optimal driving route.

In embodiments, the controller may be configured to change at least one of vehicle speed or vehicle direction in dependence on the determined property.

In an aspect, there is vehicle comprising a system of any aspect or embodiment described herein.

In embodiments, the array of ultrasonic elements may be mounted to the front of the vehicle and orientated forwards and downwards.

In embodiments, the array of ultrasonic elements may be mounted to the front bumper of the vehicle.

In an aspect, there is a method of operating a system for controlling a vehicle. The method comprises: providing a signal to an array of ultrasonic elements. Wherein the array of ultrasonic elements comprises one or more conductive pathways arranged on a surface of a substrate; and wherein the substrate is a vehicle body member or the substrate is arranged for attachment to a vehicle body member. The method also comprises receiving a signal from one or more ultrasonic elements of the array of ultrasonic elements; and identifying an object relative to the sensor in dependence on the received signal.

In embodiments, the method may comprise generating different signals for two or more ultrasonic elements of the array of ultrasonic elements, wherein the signals differ by one or more of phase, amplitude, frequency, pulse length or pulse shape.

In embodiments, the method may comprise generating different signals for two or more ultrasonic elements of the array of ultrasonic elements to change the direction of waves produced by the ultrasonic array.

In embodiments, the object may be a vehicle.

In embodiments, the method may comprise analysing the received signal to determine the location of the vehicle relative to the sensor.

In embodiments, the identified object may be the ground ahead of the sensor. In embodiments, the determined property of the ground may relate to the topography of the ground.

In embodiments, the method may comprise determining at least one of vehicle speed or vehicle direction in dependence on the identified object.

In an aspect, the computer software is executable to perform the method of any aspect or embodiment described herein.

In an aspect, a non-transitory, computer-readable storage medium storing instructions thereon that, when executed by one or more electronic processors, causes the one or more electronic processors to carry out the method described above.

In an aspect, a vehicle is adapted to perform the method of any aspect or embodiment described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described by way of example only, with reference to the accompanying figures.

Figure 1 A and 1B shows a cross section of a sensor of the system.

Figure 2 shows an alternative sensor arrangement.

Figure 3A and 3B shows an alternative sensor arrangements.

Figure 4 shows an alternative sensor arrangement.

Figure 5 shows a vehicle comprising a system.

Figure 6 shows a schematic of steps of a method.

Figure 7 shows an embodiment system in operation.

Figure 8 shows a schematic of a control system arrangement.

DETAILED DESCRIPTION

Before describing several embodiments of the invention, it is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. It will be apparent to those skilled in the art having the benefit of the present disclosure that the invention is capable of other embodiments and of being practiced or being carried out in various ways.

The term "vehicle" used herein may refer to but is not limited to automobiles. The term vehicles may comprise automobiles with SUV, saloon or estate body types, amongst others. The term vehicle may comprise combustion or electrically propelled vehicles. The term vehicle may comprise user driven or self-driven vehicles. A vehicle may have a forward direction and a rear direction opposite thereto. The forward direction is aligned with the normal direction of travel of the vehicle. A vehicle may have a front, rear and side ends. The front end is the end facing in the forward direction.

The term "vehicle body member" used herein, may refer to a body panel of a vehicle, this may comprise an external surface of a vehicle. A non-limiting example of a vehicle body member comprise a bumper of an automobile.

The term "ultrasonic element" used herein may refer to an element capable of converting an electrical signal into an ultrasonic wave and/or capable of converting a mechanical input into an electrical signal. The term "ultrasonic element" used herein may comprise ultrasonic receivers, transmitters or transceivers. A non-limiting example of an "ultrasonic element" comprises a piezo electric element.

The term "ultrasonic" used herein may pertain to a sonic wave of a frequency higher than the human upper audible limit. For example, an ultrasonic wave may comprise a propagating mechanical vibration of the order of 20 kHz or higher.

The term "array" used herein in reference to ultrasonic elements may refer to but is not limited to an arrangement of multiple ultrasonic elements. For example, the array may comprise elements in a one-dimensional linear arrangement or two-dimensional grid arrangement. The spacing of the elements, may be regular, irregular or regularly offset.

The term "substrate" used herein may refer to but is not limited to any substance or material to which or in which a conductive pathway may be applied.

The term "conductive pathway" used herein may refer to but is not limited to any electrically conductive pathway. Non-limiting examples comprise wiring, electrically conductive tracks and solder amongst others. A particular but non-limiting example of a conductive pathway comprises tracks formed from screen printing electrically conductive ink.

The term "film" used herein, may refer to but is not limited to a sheet material of 500 micrometres thickness or less.

The term "electrical contact" used herein may refer to but is not limited to a contact between two objects sufficient to conduct electricity to an extent suitable for use with electronic circuitry.

The term "digitated" used herein may refer to an arrangement comprising substantially parallel fingers, for example a in a comb-like arrangement. The term "interdigitated" used herein, may refer to two opposed digitated structures. In particular, the term may refer to an arrangement where the parallel fingers of one digitated arrangement are positioned in the spacing between parallel fingers of a second digitated structure.

The term "ground topography" used herein, may refer to any aspect of the, elevation, angle, surface texture or any other feature of the spatial properties of the ground.

Referring to Figure 1A a sensor 100 is shown in cross section. The sensor 100 for use with a system 800. The sensor 100 comprises a substrate 102. An electrically conductive pathway 104 is attached to a top surface of the substrate 102. The conductive pathway in the illustrated embodiment comprises a conductive track 104.

A portion of the conductive track 104 functions as a contact element 106. A piezo electric film 108 is placed over at least a portion of the track 104 and substrate panel 102, and is in electrical contact with the contact element 106. The sensor 100 is operated by a control system 801 shown in figure 8.

The substrate 102 of the sensor 100 in figure 1A is shown as a vehicle body member to which the track 104 and piezoelectric film 108 are applied. Thus, in this embodiment, the substrate 102 is also the vehicle body member. However, it is envisioned that the present invention may also encompass embodiments where the substrate is a separate component that is adapted to be attached to a vehicle body member, as shown in figure 1B. In figure 1 B, the conductive track 104 is attached to a separate substrate layer 102'. The substrate layer 102' is shown in figure 1B attached to a surface of vehicle body member 102.

In accordance with the embodiment shown in figure 1A, the substrate 102 may be a vehicle body member. A non-limiting example of a substrate that is a vehicle body member may comprise a polymer front bumper panel for an automobile. A conductive pathway 104 and piezo electric film 108 then may be applied to the surface of the bumper panel. Alternatively, and in accordance with the embodiment shown in figure 1 B, the substrate 102' may comprise a sheet or layer of material to which the conductive pathway 104 and piezo electric film 108 are applied. The substrate 102' itself may then be attached to a vehicle body member. In a further non-limiting example, the substrate 102' may be a polymer film with an adhesive backing that is adhered to a vehicle body member (e.g. a front bumper panel) before or after the conductive pathway 104 and optionally the piezo electric film 108 has been applied. In both variants embodied by figures 1A and 1B, the substrate 102, 102' functions as a medium to which the conductive pathway 104 and piezo electric film 108 are applied.

The conductive pathway 104 may be provided by any electrically conductive medium that can be applied to a substrate 102, 102'. For example, the conductive pathway 104 may comprise a metallic strip, wiring, or any other element capable of conducting an electrical signal. The conductive pathway 104 may be printed, embedded, adhered, etched into the surface or applied to the substrate by any other known method. Any number of conductive pathways may be applied to the substrate. The term "electrically conductive" may be considered as having a sufficient electrical conductivity to be suitable for use as part of electronic circuitry.

The conductive pathway comprises a plurality of contact elements 106. A contact element 106 may be at least a portion of the conductive pathway 104 that electrically contacts the piezo electric film 108. Thus, the conductive pathway 104 functions to transmit electrical signals to and/or from the piezo electric film 108 via the contact elements 106. The contact elements 106 may therefore be considered as electrodes contacting the piezo electric film 108.

In embodiments, the conductive pathway 104 may be shaped, insulated or otherwise arranged to prevent unwanted portions of the conductive pathway 104 from electrically connecting to the piezo electric film 108. For example, an electrically insulating barrier may be placed over portions of the conductive pathway to electrically insulate it from the piezo electric film 108. Alternatively, the piezo electric film 108 may only be deposited on the contact elements 106, so that no electrical connection is formed with the remainder of the conductive pathway 104. Alternatively, the conductive pathway 104 may be arranged away from the piezo electric film 108, by e.g. by embedding within the substrate 102, 102' or arranging on an opposite surface of the substrate.

The contact elements 106 may be portions of the conductive pathway 104 that are shaped, uninsulated or otherwise arranged to electrically connect to the piezo electric film 108.

In embodiments, the conductive pathway 104 may comprise a pathway comprising one or more of nickel, silver, copper, gold, ink, indium tin oxide, carbon, doped semiconductors, conductive polymers (e.g. PEDOT), or inks comprising any of the former.

The piezo electric film 108, may comprise a single film applied to the substrate 102 in electrical contact with a plurality of contact elements 106. Alternatively, the piezo electric film may comprise any number of discrete films that are applied to the substrate to make electrical contact with one or more contact elements 106. A piezo electric film may be a thin piece (e.g. between 10 and 300 micrometres) of piezo electric material, which may become strained when an electric field is applied. The piezo electrical film 108 may also generate an electrical charge or potential in response to an applied mechanical stress.

The piezo electric film 108 may comprise a piezo-crystal, piezo-ceramic, piezo-polymer or a hybrid piezo-material. Non-exhaustive examples may comprise quartz, lead zirconate, PVT, semiconductor crystals such as Group III-VI and II-V materials, polyvinylidene fluoride or any other known piezoelectric material. In particular embodiments, the piezoelectric film may comprise polyvinylidene fluoride or a copolymer of vinylidene fluoride and trifluoroethylene. The piezo electric film may comprise a piezoelectric polymer cast as a film less than 500 micrometres thick, or between 10 and 300 micrometres thick, or between 20 to 200 micrometres thick or between 40 and 100 micrometres thick, and or any range comprising any combination of the aforesaid values.

In Figure 1, the piezo electric film 108 is shown over the conductive pathway 104, however, the piezo electric film 108 may alternatively be arranged against the substrate and one or more conductive pathways 104 arranged over the piezo electric film 108.

The piezo electric film 108 may be caused to generate a sonic wave by applying one or more electrical signals to the conductive pathway 104. The contact elements 106 of the conductive pathway 104 may transfer the electrical signal(s) to the piezo electric film 108, causing the piezo electric film 108 to mechanically deform. This mechanical deformation may be induced at frequencies and amplitudes sufficient to generate an ultrasonic wave. Thus, an electric signal may be applied to actuate the piezo electric film, to create an ultrasonic wave. As such the conductive pathways 104, contact elements 106 and piezo electric film 108 collectively form ultrasonic element. The ultrasonic element may emit an ultrasonic wave in a direction that is generally perpendicular to the surface that they are applied to. The piezo electric film 108 may also be mechanically deformed by an incident vibrational wave. Mechanical deformation of the piezo electric film 108 may generate a voltage potential in the piezo electric material, which may result in the generation of an electric signal transmitted in the conductive pathway 104 via contact element 106. Thus, an electric signal may also be created by an incident vibrational wave.

Where the contact element 106 contacts the piezo electric film 108, the resulting arrangement may function to create and or detect vibrational waves. The piezo electric film 108 may function as an ultrasonic transmitter by converting an electrical signal to an ultrasonic wave. Similarly, the piezo electric film 108 may function as an ultrasonic receiver by converting an incident vibrational wave to an electrical signal. Optionally, the piezo electric film 108 may function as an ultrasonic transceiver by being operable to perform both transmitting and receiving functions. An array of ultrasonic elements, each comprising a conductive pathway 104, contact elements 106 and piezo electric film 108 as hereinbefore described, may function as an array of emitters, receivers or sensors. An individual ultrasonic element may be considered as an individual emitter, receiver or sensor.

The sensor 100 of the invention may contain any number of such ultrasonic elements.

Vehicle body members may be produced comprising many ultrasonic elements. For example, a vehicle body member, such as an automobile bumper, may comprise at least 10, 50, 100, 200, 500 or 1000 ultrasonic elements. Fitting conventional ultrasonic elements, such as conventional parking distance sensors, to a vehicle body member requires a substantial amount of wiring. which prohibits the fitting of ultrasonic elements in large numbers. However, the ultrasonic elements hereinbefore described of the sensor 100 may be applied with a smaller spacing between the elements than would otherwise be possible with conventional ultrasonic elements. The ultrasonic elements of the sensor 100 may be arranged in one-dimensional or two-dimensional arrays, these may extend along the width of a vehicle body member and/or optionally along the height of a vehicle body member. The different sensors of an array can also be mounted in different orientations, meaning the array can provide greater sensor coverage, and may be used for different functions.

The sensor 100 has many advantages over existing prior art ultrasonic sensors such as conventional ultrasonic parking sensors. These comprise improved functionality such as substantially increased resolution, improved directional discrimination, redundancy, etc. and improved visual appearance.

The sensor 100 can be applied to vehicle body members to form an array of sensor elements comprising a large number of individual ultrasonic elements. The sensor of the present invention provides an array having a large amount of redundancy.

Therefore, the sensor may still function if some of the ultrasonic elements become damaged. Sensor elements of the invention can be closely spaced meaning they can also operate as a phased array. Because large numbers of sensor elements can be fitted to a vehicle body member, the resolution and therefore functionality is also

improved over prior art water detection sensors.

The ultrasonic elements may be connected without the need for conventional wiring which would otherwise be prohibit the use of a large number of conventional sensors in a single panel.

Referring to figure 2, an alternative embodiment sensor 200 comprising an array of ultrasonic elements is shown. Similar to figure 1A, the sensor comprises a conductive pathway 104, applied to a surface of the substrate 202. A piezo electric film 108 is applied to the conductive pathway 104 to form an electrical connection with a contact element 106 of the conductive pathway 104. In the embodiment shown in figure 2, the substrate 202 is the vehicle body member. The substrate 202 further comprises one or more cavities 204. As shown in figure 2, the cavity 204 is aligned to be coincident to the contact element 106. For example, the centre of the ultrasonic element may be positioned over the centre of the cavity 204. Thus, where an ultrasonic element is formed by a contact element 106 in electrical contact with the piezo electric film 108, the cavity 204 may be arranged behind the ultrasonic element. In embodiments, the substrate may be a layer applied to a vehicle body member, in which case, the cavities 204 may be in the substrate or the vehicle body member. The cavity does not need to be limited to an indentation into the substrate or vehicle body member as shown in figure 2. The cavities may, for example, be formed from material extending above the surface of the substrate or body member, e.g. by applying material in a ring shape to the surface, or by forming the substrate/body member to comprise raised walls.

The cavities may function to provide a volume behind the piezo electric film. In embodiments, this may improve the freedom of vibration of the ultrasonic elements. The cavities 202 may also function to dampen undesirable waves reflected from the vehicle body member or substrate. The cavities may be sized so that a wave from an ultrasonic element and incident to a cavity 202, is reflected out of the cavity 202 such that when the wave returns to the ultrasonic element, it is in-phase with a wave emitted outwards from the ultrasonic element. In an embodiment, the depth of the cavity 202 may be half of the resonant wavelength of the ultrasonic element. Alternatively, the indentation may be sized to dampen or cancel the incident wave. In an embodiment, the cavity 202 may be sized to cancel the wave, or may have a volume determined with a cavity resonance selected in dependence on the resonant frequency of the ultrasonic element.

Referring to figure 3A, a sensor 300 is shown in plan form. The sensor 300 comprises a substrate 102, onto which conductive pathways 104a, 104b are arranged. The embodiment shown in figure 3 comprises two sets of conductive pathways 104a, 104b, each set of pathways 104a, 104b arranged as a digitated structure, comprising parallel branches. In figure 3A, the two digitated arrangements of conductive pathways are arranged so that their parallel branches are interlocking, i.e. interdigitated. The contact elements 106 are located at the end of each of the parallel branches, with the piezo electric film 108 laid over the top of the contact elements 106. In this manner, an ultrasonic element is formed between adjacent pairs of contact elements 106 from each conductive pathway 104a, 104b. Figure 3B shows an alternative arrangement of the two conductive pathways 104a, 104b. Both pathways are arranged as an interdigitated structure, but rather than interlocking, the parallel branches are spaced apart and offset. By arranging the conductive pathways in a digitated arrangement, the contact elements can be spaced closer together allowing for a sensor with a greater density of ultrasonic elements. This in turn allows a further improvement of resolution to be achieved. The term "digitated structure" may refer to but is not limited to any arrangement comprising parallel terminal conductive pathways, i.e. shaped like a comb.

Referring to figure 4, an alternative embodiment of a sensor 400 is shown comprising a first conductive pathway 104a arranged against a surface of substrate 102. A piezo electric film 108 is arranged over the first conductive pathway 104a. A second conductive pathway 104b is arranged over the piezo electric film 108. Thus, two or more conductive pathways 104a, 104b may be separated by the piezo electric film 108. This arrangement may allow the contact elements 106 to be spaced closer together, allowing for a greater number of ultrasonic elements to be placed on the vehicle body member. In embodiments, where the conductive pathways 104a, 104b are arranged in digitated structures, the conductive pathways 104a, 104b may also be separated by the piezo electric film 108.

In embodiments, the sensor may comprise an outermost elastomeric coating (not shown). For example, at least one layer of an elastomeric paint, varnish, or a protective layer. The outermost layer may comprise a layer of a lower stiffness than the underlying ultrasonic element, to prevent the layer from significantly restraining oscillation of the ultrasonic element.

Referring to figure 5, an embodiment vehicle 500 is shown. The embodiment vehicle comprises a vehicle body member 501, comprising a sensor 100 attached thereto.

Vehicle body member 501 shown in figure 5 are the front and rear bumper/fender. However, the invention may be applied to any vehicle body member of any suitable vehicle type.

In some embodiments, the body members may be arranged on any one of the front, rear, left and right sides, automobile underfloor or automobile roof. The automobile may comprise an automobile body panel comprising ultrasonic arrays directed to emit or receive ultrasonic waves over an arc around the perimeter of the automobile of substantially 360 degrees, 270 degrees, 180 degrees, 90 degrees or 45 degrees, or an arc in any range formed from any of these preceding values. In embodiments, the automobile may comprise a plurality of automobile body panels each comprising sensor arrays.

In embodiments, the sensor may be mounted to a vehicle in an aspect that is directed generally forwards and/or downwards. In embodiments, the sensor may be arranged so that the ultrasonic elements of the sensor extend in a lateral direction, across at least a portion of the front end of the vehicle.

In embodiments, the sensor may be formed so that the ultrasonic elements extend across substantially the width of the front and/or rear end of the vehicle.

In embodiments, the array may comprise a plurality of rows of ultrasonic elements. In embodiments, the rows may be aligned horizontally and/or vertically.

In embodiments, the lateral sides of the vehicle may comprise the sensors as shown in figure 5 by vehicle body members 502. In embodiments, the sensors may be applied to a vehicle to provide coverage of substantially the entire perimeter of the vehicle.

Referring to figure 6, a method 600 of operating the system 800 is shown. The method 600 comprises the step 601 of providing an electronic emission signal to an array of ultrasonic elements 100, the electronic emission signal configured cause the array of ultrasonic elements to generate an ultrasonic wave. As described above, the array of ultrasonic elements comprises one or more conductive pathways arranged on a surface of a substrate; and the substrate is either a vehicle body member or the substrate is arranged for attachment to a vehicle body member. The method 600 also comprises the step 602 of receiving a signal caused by the wave reflected from an object. The method 600 also comprises the step 603 of determining an object location relative to the sensor in dependence on the received signal.

Referring to figure 7, an ultrasonic wave 701 emitted from the sensor array is shown, the wave may be directed generally forwards and/or rewards of the vehicle 500. A reflected wave 702 may be created by wave 701 contacting an object 705. The reflected wave may be directed back towards the vehicle 500. The reflected wave may mechanically distort the piezoelectric film 108 of the ultrasonic elements causing the ultrasonic elements to create a voltage potential thereacross, and thus generate an electrical signal in the conductive pathways. The electrical signal may be analysed by the control system 801 to determine the location of the object 705 relative to the sensor.

For example, the timing between the signal creating wave 701 being emitted by the sensor array and the signal of wave 702 being received at the sensor array may be used to determine the time of flight of the emitted wave 701 and reflected wave 702. The distance of the object can then be derived using the speed of propagation of an ultrasonic wave in air. In embodiments, frequency shift, amplitude and directionality of the signal relating to reflected wave 702 may also be used. In embodiments, the electrical signals generated by each of the elements may each be analysed to determine an ultrasonographical image of at least a portion of the shape of an object.

The object may be identified in dependence on any of: the time duration between an emitted wave and the detection of a reflected wave, the time duration between two or more reflected waves, changes in frequency between emitted and reflected waves, changes in frequency between reflected waves, intensity of reflected waves, directionality of reflected waves.

The reflected wave may exhibit a frequency shift, or the timing may vary between received waves, or a plurality of reflected waves may be received. In particular embodiments, the time of flight between an emitted wave and a reflected wave may be used to determine distance of an object from the sensor.

In embodiments, the control system 801 may generate different signals for two or more ultrasonic elements of the array of ultrasonic elements. In embodiments, different signals may be generated for different ultrasonic elements, based on their position in the array of ultrasonic elements. In embodiments, the signals may differ by one or more of phase, amplitude, frequency, pulse duration or pulse shape.

The control system 801 may be operable to generate signals having a periodic shape. The signals may produce an ultrasonic wave of frequency 20 kHz to 400 kHz, 30 kHz to 120 kHz, 40 kHz to 60 kHz or any combination of the aforesaid ranges.

In an embodiment, the signals to elements in an array may differ in phase, based on an elements position in the array. The control system 801 may deliver the same signal, but different in phase to different elements in the array, or the control system 801 may generate a single signal, that is delayed by a different extent to each of the elements in the array, depending on their position.

In embodiments, the difference in signals may be used to change the direction of the wave produced by the array of ultrasonic elements. For example, the phase of a signal may be altered to provide beam steering, where the array of ultrasonic elements functions as a phased array.

In embodiments, the wave may be directed using beam steering, to direct the beam laterally of vertically. That is, the beam may be directed towards the left or right sides of the vehicle, or directed downwards e.g. towards the ground, or upwards, e.g. towards the horizon or above the horizon.

In embodiments, beam steering may be used to focus waves from the array of ultrasonic elements, to direct the wave to a target or region ahead of the array. The focussing of the wave may improve the resolution of the sensor at that point. In embodiments, beam steering may be used to scan a region ahead of the sensor. Beam steering may be particularly beneficial when the sensor is used to generate an ultrasonographical image of an object.

In embodiments, waves from the array may be directed to scan ahead of the vehicle by focussing on sequential point. This may allow the array to first coarsely locate an object ahead of the vehicle, then focus on that identified object to improve the resolution of detection. Beam steering may also be used to extend the field of view of the sensor array.

In embodiments, the sensor may operate without beam steering to sense ahead of the vehicle. Beam steering may then be used to focus on any identified regions of interest ahead of the vehicle, to provide higher resolution sensing in that region.

In embodiments, the signals received by each sensor in the array may be analysed in dependence on their position in the array. For example, the timings of a signal corresponding to an incident wave may be compared across the array to determine the direction of origin of the wave.

In further embodiments, the sensor may be operated by determining a first signal to emit a first set of ultrasonic waves without beam steering. The reflected waved may be analysed to determine a location of an object. The location of the object may be used to determine a second signal for generating a second set of ultrasonic waves. The second signal may be determined so that the second set of waves are focussed on the determined location of the object.

In embodiments, the sensor may be operated by determining a series of signals so that the sensor emits a series of waves, each focussed at a different angle from the sensor. Thus, the sensor may be operated to sweep focussed ultrasonic waves over an area.

In embodiments, the array may be used as an input to the vehicle control unit, to control the vehicle when travelling in traffic moving at low speeds or intermittently. The sensor array provides increased resolution over short distances than systems such as LIDAR. Thus, the present invention may be used to provide more accurate control of the vehicle. The sensor array may be used to determine the distance between the vehicle and an object ahead of the vehicle. The object may be another vehicle. The distance between the vehicle and the object may be used to determine the speed and direction of the vehicle. For example, when an object ahead of the vehicle moves forward, the increased distance and the direction of motion may be determined by the control system 801. Data relating to the increased distance and direction may be provided to the vehicle control unit, and the direction speed of the vehicle adjusted to follow the object.

In embodiments, the array may be used to determine ground topology ahead of the vehicle. This may be used as an input for an autonomous driving of the vehicle. The steering and speed of the vehicle may be controlled in dependence of the determined ground topology. In embodiments, if the prominence of a part of the measured topography exceeds a threshold, then that part of the topography may be identified as a hazard. The motion of the vehicle may be controlled to avoid the hazard. Topography may include elevation, angle, surface texture or any other features relating to spatial properties of the ground. In embodiments, the control system 801 may analyse the topography of the ground to identify optimal conditions or an optimal driving route. In embodiments beam steering may be used to scan the ground ahead of the sensor, so that an ultrasonographical representation of the ground is obtained.

The system may perform additional functions as well as the purpose referred to herein. For example, the system may be used as any one of: apparatus for emitting sounds from a vehicle, a parking sensor; a sensor for determining the depth of a vehicle; a sensor for near zone imaging of a vehicle; as a microphone for detecting external sounds.

The system may perform different functionalities depending on the current state of the vehicle. Non-limiting example vehicle state include: where the vehicle is in parking mode, the sensor may be operated as a parking sensor; where the vehicle is off-road, or moving in traffic, it may be operated as a near zone imaging device for controlling speed and/or steering, when the vehicle is in motion, it may be used to emit sounds; and where the vehicle is occupied, it may be used as a microphone or for emitting sounds.

Where the vehicle is in two concurrent states, changing between functionalities may be operated by the control system 801 or vehicle control unit. For example, where a vehicle in in motion, the sensor may be used as a near field sensor, however, when the control system 801 identifies a pedestrian or car in a hazardous position, the control system 801 may operate the sensor to emit a warning sound to the pedestrian, before resuming operation as a near field sensor.

Referring to figure 8, there is illustrated a simplified example of the control system 801 such as may be adapted to implement the method of Figure 6 described above. The control system 801 comprises one or more controllers 810 and is configured to generate a signal to one or more ultrasonic elements of the array of ultrasonic elements, receive a signal from one or more ultrasonic elements of the array of ultrasonic elements, and determine a property of an object relative to the array of ultrasonic elements in dependence on the received signal.

It is to be understood that the or each controller 810 can comprise a control unit or computational device having one or more electronic processors (e.g., a microprocessor, a microcontroller, an application specific integrated circuit (ASIC), etc.), and may comprise a single control unit or computational device, or alternatively different functions of the or each controller 810 may be embodied in, or hosted in, different control units or computational devices. As used herein, the term "controller," "control unit," or "computational device" will be understood to include a single controller, control unit, or computational device, and a plurality of controllers, control units, or computational devices collectively operating to provide the required control functionality. A set of instructions could be provided which, when executed, cause the controller 810 to implement the control techniques described herein (including some or all of the functionality required for the method described herein). The set of instructions could be embedded in said one or more electronic processors of the controller 810; or alternatively, the set of instructions could be provided as software to be executed in the controller 810. A first controller or control unit may be implemented in software run on one or more processors. One or more other controllers or control units may be implemented in software run on one or more processors, optionally the same one or more processors as the first controller or control unit. Other arrangements are also useful.

In the example illustrated in Figure 8, the or each controller 810 comprises at least one electronic processor 820 having one or more electrical input(s) 822 for receiving one or more input signal(s) such as from ultrasonic elements within the array, and one or more electrical output(s) 824 for outputting one or more output signal(s) such as control signals to ultrasonic elements within the array. The or each controller 810 further comprises at least one memory device 830 electrically coupled to the at least one electronic processor 820 and having instructions 840 stored therein. The at least one electronic processor 820 is configured to access the at least one memory device 830 and execute the instructions 840 thereon so as to generate a signal to the one or more ultrasonic elements of the array of ultrasonic elements and determine a property of an object relative to the array of ultrasonic elements in dependence on the received signal.

The, or each, electronic processor 820 may comprise any suitable electronic processor (e.g., a microprocessor, a microcontroller, an ASIC, etc.) that is configured to execute electronic instructions. The, or each, electronic memory device 830 may comprise any suitable memory device and may store a variety of data, information, threshold value(s), lookup tables or other data structures, and/or instructions therein or thereon. In an embodiment, the memory device 830 has information and instructions for software, firmware, programs, algorithms, scripts, applications, etc. stored therein or thereon that may govern all or part of the methodology described herein. The processor, or each, electronic processor 820 may access the memory device 830 and execute and/or use that or those instructions and information to carry out or perform some or all of the functionality and methodology describe herein.

The at least one memory device 830 may comprise a computer-readable storage medium (e.g. a non-transitory or non-transient storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational devices, including, without limitation: a magnetic storage medium (e.g. floppy diskette); optical storage medium (e.g. CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g. EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

Example controllers 810 have been described comprising at least one electronic processor 820 configured to execute electronic instructions stored within at least one memory device 830, which when executed causes the electronic processor(s) 820 to carry out the method as hereinbefore described. However, it will be appreciated that embodiments of the present invention can be realised in any suitable form of hardware, software or a combination of hardware and software. For example, it is contemplated that the present invention is not limited to being implemented by way of programmable processing devices, and that at least some of, and in some embodiments all of, the functionality and or method steps of the present invention may equally be implemented by way of non-programmable hardware, such as by way of non-programmable ASIC, Boolean logic circuitry, etc. It will be appreciated that embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage such as, for example, a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape. It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs that, when executed, implement embodiments of the present invention. Accordingly, embodiments provide a program comprising code for implementing a system or method as claimed in any preceding claim and a machine-readable storage storing such a program. Still further, embodiments of the present invention may be conveyed electronically via any medium such as a communication signal carried over a wired or wireless connection and embodiments suitably encompass the same.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. The claims should not be construed to cover merely the foregoing embodiments, but also any embodiments which fall within the scope of the claims.

Claims

CLAIMS1. A system for a vehicle, the system comprising: a sensor, the sensor comprising: a substrate, wherein the substrate is a vehicle body member or the substrate is arranged for attachment to a vehicle body member; and an array of ultrasonic elements, wherein the array of ultrasonic elements comprises one or more electrically conductive pathways deposited on the surface of the substrate; a control system, the control system comprising one or more controllers, the control system configured to: generate a signal to one or more ultrasonic elements of the array of ultrasonic elements; receive a signal from one or more ultrasonic elements of the array of ultrasonic elements; and determine a property of an object relative to the array of ultrasonic elements in dependence on the received signal.
2. A system according to claim 1, wherein the one or more controllers collectively comprise: at least one electronic processor having an electrical input for receiving a signal from the one or more ultrasonic elements of the array of ultrasonic elements and an electrical output for outputting a signal to the one or more ultrasonic elements of the array of ultrasonic elements; 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 generate a signal to be output to the one or more ultrasonic elements of the array of ultrasonic elements determine the property of an object relative to the array of ultrasonic elements in dependence on the received signal.
3. A system according to claim 1 or claim 2, wherein the array of ultrasonic elements comprises at least one piezo electric film.
4. A system according to claim 3, wherein the one or more conductive pathways comprise one or more contact elements in electrical contact with at least one piezoelectric film.
5. A system according to claim 4, wherein the contact elements in electrical contact with at least one piezoelectric film form one or more ultrasonic elements of the array of ultrasonic elements.
6. A system according to any preceding claim, wherein the vehicle body member is a vehicle bumper.
7. A system according to any preceding claim, wherein at least a portion of the conductive pathway is arranged as a digitated structure on the substrate.
8. A system according to any preceding claim, wherein at least two portions of the conductive pathway is arranged as an interdigitated structure.
9. A system according to any preceding claim, wherein the conductive pathway comprises at least two portions separated by the piezo electric film.
10. A system according to any preceding claim, wherein the array of ultrasonic elements comprises at least 10, 50, 100, 200, 500 or 1000 elements.
11. A system according to any preceding claim, wherein the controller is configured to generate different signals for two or more ultrasonic elements of the array of ultrasonic elements, wherein the signals differ by one or more of phase, amplitude, frequency, pulse length or pulse shape.
12. A system according to any preceding claim, wherein controller configured to generate different signals for two or more ultrasonic elements of the array of ultrasonic elements to change the direction of waves produced by the ultrasonic array.
13. A system according to any preceding claim, wherein the object comprises a second vehicle.
14. A system according claim 13, wherein the determined property comprises the location of the second vehicle relative to the sensor.
15. A system according to any preceding claim, wherein the object comprises the ground ahead of the sensor.
16. A system to claim 15, wherein the determined property comprises the topography of the ground ahead of the sensor.
17. A system according to any preceding claim, wherein the controller is configured to change at least one of vehicle speed or vehicle direction in dependence on the determined property of the object.
18. A vehicle comprising a system of any proceeding claim.
19. A vehicle according to claim 18, wherein the array of ultrasonic elements is mounted to the front of the vehicle and orientated forwards and downwards.
20. A vehicle according to claim 18 or 19, wherein the array of ultrasonic elements is mounted to the front bumper of the vehicle.
21. A method of operating a system for controlling a vehicle, the method comprising: providing a signal to an array of ultrasonic elements, wherein the array of ultrasonic elements comprises one or more conductive pathways arranged on a surface of a substrate; and wherein the substrate is a vehicle body member or the substrate is arranged for attachment to a vehicle body member; receiving a signal from one or more ultrasonic elements of the array of ultrasonic elements; and determine a property of an object relative to the sensor in dependence on the received signal.
22. Computer software executable to perform the method of claim 21.
23. A non-transitory, computer-readable storage medium storing instructions thereon that, when executed by one or more electronic processors, causes the one or more electronic processors to carry out the method of claim 21.