Method for detecting an obstacle, detection system, vehicle, computer program product and computer-readable storage medium

Abstract

The invention relates to a method (100) for detecting an obstacle (400) lying on a trajectory of a wheel (310) of a vehicle (300), comprising: - detecting an input torque (110) from a steering input which at least partially determines the trajectory of the wheel (310), - calculating an expected value (120) of a rack (320) designed to position the wheel (310) in accordance with the steering input, for the input torque (110), - Recording a current rack value (130) for the expected value (120) of the rack (320), - determining a result (140) as to whether an obstacle is located on the trajectory of the wheel (310) based on a comparison of the expected value (120) with the current rack value (130), - Providing the result (140), wherein at least the determination of the result (140) occurs only if a plausibility condition (150) is met. Furthermore, the invention relates to a detection system, a vehicle, a computer program product, and a computer-readable storage medium.

Description

The invention relates to a method for detecting an obstacle which lies on a trajectory of a wheel of a vehicle, to a detection system, to a vehicle, to a computer program product and to a computer-readable storage medium.If a wheel is close to an obstacle, in particular to a curbstone, adverse effects can occur in the steering system. Damage to the wheel, in particular at least to the tire or the rim, is also possible. As long as a driver is steering the vehicle and the steering is mechanically in contact with the wheel, the driver can notice an obstacle during steering maneuvers and react accordingly, if necessary. If, however, the steering movement is transmitted by assistance systems (e.g. PLA) or steer-by-wire systems, the driver and possibly also the assistance system does not see or engage the obstacle. A steering system of the generic type is known from U.S. Pat. No. 11,702,128 B2 and DE 102 61 001 A1.It is therefore an object of the present invention to at least partially overcome at least one of the above-described disadvantages in the detection system for a vehicle. In particular, it is an object of the invention to provide a method for detecting an obstacle which lies on a trajectory of a wheel of a vehicle, a detection system, a vehicle, a computer program product and a computer-readable storage medium which allow particularly reliable and simple detection of an obstacle and a transmission of the detection result.The above object is achieved by a method according to the invention, by a detection system according to the invention, by a vehicle according to the invention, by a computer program product according to the invention and by a computer-readable storage medium according to the invention as claimed in the independent claims. Further features and details of the invention are evident from the dependent claims, the description and the drawings. Features and details which are described in connection with the method according to the invention naturally also apply in connection with the detection system according to the invention and / or in connection with the vehicle according to the invention and / or in connection with the computer program product according to the invention and / or in connection with the computer-readable storage medium according to the invention and vice versa, so that with regard to the disclosure reference is or can always be made reciprocally to the individual aspects of the invention.According to the invention, a method for detecting an obstacle which lies on a trajectory of a wheel of a vehicle is provided, comprising:detecting an input torque from a steering input which at least partially determines the trajectory of the wheel, in particular by a computing unit and / or a steering input sensor,calculating an expected value of a toothed rack for the input torque, in particular by the arithmetic unit, wherein the toothed rack is designed to position the wheel according to the steering input,detecting a current rack value for the expected value of the rack, in particular by the arithmetic unit and / or a rack sensor,determining a result whether an obstacle is located on the trajectory of the wheel based on a comparison of the expected value with the current rack value, in particular by the computing unit,providing the result, in particular by the computing unit and / or an output interface,wherein at least the determination of the result takes place only when a plausibility condition is fulfilled.In other words, a method for detecting an object which is located in the path of a wheel of a vehicle can be provided. According to the method, a steering input may be determined that determines in which position the wheel should be located. From this steering input, it is possible to calculate how a toothed rack would have to behave in order to adjust the wheel according to the steering input. The behavior of the rack may be measured and compared to the calculated behavior to determine whether an obstacle is present. This may occur when at least one condition is met that makes the determination plausible. The result can be made available.The method can be implemented as a computer-implemented method.The method steps can run at least partially simultaneously and / or successively in time, wherein the sequence of the method steps is not limited by the sequence indicated, so that individual steps can be carried out in different sequences. Further, individual or all steps may be repeatedly performed.Detection of an obstacle can be understood to mean that the presence of an object in the travel path of the wheel is detected. An obstacle may be, for example, a sidewalk, another vehicle, a boundary finding, a bollard, or another potential hazard. The method is directed to vehicles. The vehicle can be a motor vehicle in particular. A motor vehicle can in principle be any type of motor-driven vehicle. The motor vehicle can be designed as a land vehicle, water vehicle or aircraft. In particular, the motor vehicle can be a passenger car or truck. The motor vehicle may further have an internal combustion engine and / or an electric motor. It can likewise be provided that the motor vehicle is exclusively electrically driven.It can be provided that the method is applied to only one wheel. Furthermore, it can be provided that the method is applied at least to the wheels of a steering axle or to all wheels of a vehicle. It is likewise conceivable for the method to be applied to wheels which are located on a side of the vehicle on which an obstacle is expected, for example to the side of a motor vehicle which is aligned with a curb during a parking process.The vehicle may have at least one steering assistance system which is designed to at least partially take over the steering of the vehicle. For this purpose, the steering assistance system can move the wheel, in particular by adjusting a toothed rack which is connected to the wheel. The steering can take place alternatively or in addition at least partially manually. In this case, the moment required to position the wheel is applied at least partially by a person. It can be provided that a motor assists the movement in this case. The strength of the support (also referred to below as support level) can vary. Furthermore, it is possible that the steering is implemented as steer-by-wire steering. Steer-by-wire steering can be understood to mean steering in which a steering command is forwarded from a sensor (in particular the steering wheel) via one or more control units exclusively electrically to an electromechanical actuator which executes the steering command.The trajectory can be understood to mean the path along which a body moves and / or along which a body will move. Within the scope of the invention, the path along which the wheel would move if no obstacle were to be on the path can be understood in particular. In this case, any contact, in particular also in the future, of the obstacle with the wheel or a part of the wheel can already represent an intervention in the trajectory. It can be provided that the trajectory of the wheel determines the trajectory of the vehicle overall at least partially, in particular overall.Detection of an input torque can be understood to mean the determination of the presence of an input torque and / or the quantitative detection of the input torque. The detection can be effected in particular by a computing unit and / or a steering input sensor. In this case, it can be provided that the arithmetic unit actuates the steering input sensor, carries out a measurement and reads in the recorded measured values. The steering input may at least partially determine the trajectory of the wheel. In other words, by means of the steering, it is possible to define at least partially, in particular completely, how the wheel is to be arranged in order for the wheel to follow a specific path.The calculation of an expected value of a rack can be understood as the determination of a value which, on the basis of the input torque, corresponds to a corresponding state of the rack. For example, a steering torque to the right could correspond to a shift of the rack to the left, which in turn aligns the wheel to the right. In this example, the expectation value could include the rack being moved 10 mm to the left at a speed of 5 mm / s. The expected value can comprise at least a rack speed or a rack position and their time curves.A rack which is designed to position the wheel in accordance with the steering input can be understood to mean a wheel actuating device which is suitable for positioning a wheel with respect to at least one axle, in particular the longitudinal axis, of the vehicle. In principle, other and / or further devices for adjusting the wheel, for example wire cables, levers and rods, are also conceivable, to which the expected value can be related without departing from the scope of the present invention.When acquiring a current rack value for the expected value of the rack, at least that value which corresponds to the expected value is determined. In other words, at least one actual value for the toothed rack is determined. It can be provided that a plurality of expected values have been calculated. Then, the current rack value can be acquired at least for a part of the expected values, in particular all of them. The current rack value can comprise at least one rack speed or a rack position and the time curves thereof.The determination of a result of whether an obstacle is located on the trajectory of the wheel can be understood as Boolean determination, in the sense that either an obstacle is present or not. Alternatively or in addition, it can be provided that a metric is provided for the obstacle which is specific for the influence of the obstacle, for example. For example, a distinction could be made between a large and a small obstacle, or one which has a large or a small influence on the rack position.The result is determined based on a comparison of the expected value with the current rack value. This means that both values are used for determining the result and are related to one another. In the determination, it can be provided that a difference is formed between the expected value and the current rack value and, in particular, this difference is compared with a threshold value. If the difference is outside a range defined by the threshold, the determination may comprise the result that an obstacle is present. If the difference is within a range defined by the threshold, the determination may include the result that there is no obstacle.Providing the result can be understood to mean providing the result. This can be effected, for example, via an output interface. This output interface can be controlled by a computing unit. It can furthermore be provided that the result is provided on a bus, so that the result is also available for other vehicle systems, in particular an assistance system.It can furthermore be provided that a steering input is at least carried out or an existing steering input is adapted on the basis of the provided result. For example, the turning of the wheel can be reduced or stopped if an obstacle is detected.According to the invention, at least the determination of the result takes place only when a plausibility condition is fulfilled. In other words, it can be provided that at least parts of the method are executed only when a plausibility condition is fulfilled. The plausibility condition can comprise at least one threshold value or a predefined value, which is specific to the fact that the determination of the result can be carried out reliably and in a robust manner. For example, the plausibility condition can comprise that the result is determined only when the expected value is successfully determined. Furthermore, the plausibility condition can be linked to the presence of a driving mode of the vehicle, in particular to driving assistance active or not driving assistance inactive. Further plausibility conditions are discussed within the scope of the dependent claims.Overall, the method according to the invention offers the advantage that a detection of an obstacle is provided, which allows a particularly reliable and simple detection of an obstacle and a forwarding of the detection result. The detection of the input torque serves as a starting point, on the basis of which an associated expected value is determined. This represents both a simple and robust way of determining which state the steering system should have without obstacle. By acquiring the current rack value, one or more easily determinable values are determined which are specific to the actual state of the steering system. The robustness of the method is increased in that at least one plausibility condition must be fulfilled in order for the determination to be carried out. This is based on a comparison of the expected state of the steering system with the actual state of the steering system on the basis of the status of the rack, which represents a particularly simple and at the same time reliable way of determining. This result is subsequently provided, as a result of which other driving systems and / or persons can also take the result into account, such that damage to the vehicle or the environment can be avoided.Within the scope of the invention, it can be advantageous that an output of the result is provided, in particular via a bus interface. In other words, it is conceivable that the method also comprises transmitting the result. The output can be effected at least to a person located in the vehicle, in particular a driving person, or to a vehicle system, in particular an assistance system. The output can be at least optically, in particular as a warning symbol, acoustically, in particular as a warning tone, or haptically, in particular as a vibration or impulse at the steering system. The bus interface can be understood as part of a bus system which connects field devices such as measurement sensors and control elements in the vehicle for communication with a control unit.Within the scope of the invention, it is conceivable that the plausibility condition is determined at least by a comparison of a setpoint value at least for a vehicle speed, a rack speed, a rack position or an assistance level. The set point may include at least one of an upper and a lower set point. Accordingly, at least one set value range can be provided. It can be provided that the (upper) setpoint value for the rack position excludes a range around the end stops of the rack. The (lower) setpoint value for the rack speed can prescribe a specific minimum rack speed. It can likewise be provided that a setpoint value specifies a specific support level. It can be provided that all the stated variables determine the plausibility condition. This offers the advantage that the method is thereby particularly robust with respect to errors and, in addition, fewer or no false positive results are determined.It can be provided within the scope of the invention that a debouncing is provided at least for the detection of an input torque or the detection of a current rack value. The debouncing can be implemented at least in hardware, in particular as an RC element in combination with a Schmitt trigger, or in software-implemented fashion. The detection accuracy is increased by the debouncing, so that the determination of the result overall becomes more robust and less susceptible to interference.It is furthermore conceivable that the input torque comprises at least one hand torque or one motor torque and the detection of the input torque is dependent on a driving operating mode, the at least one assistance mode, in which an assistance system of the vehicle at least partially takes over the steering, or a manual mode, in which the steering of the vehicle is carried out at least partially by a person. In other words, the input torque can be detected both for steering inputs by a person and by a vehicle system, in particular an assistance system. This can be effected depending on a driving operating mode. This also leads to the result being determined overall more robust and less susceptible to faults.The above object is furthermore achieved by a detection system according to the invention for detecting an obstacle which lies on a trajectory of a wheel of a vehicle, in particular is designed to carry out a method according to the invention, having a computing unit which is designed to perform a processing operation,detecting an input torque from a steering input which at least partially determines the trajectory of the wheel,calculating an expected value of a rack configured to set the wheel according to the steering input for the input torque,detecting a current rack value for the expected value of the rack,determining a result whether an obstacle is on the trajectory of the wheel based on a comparison of the expected value with the current rack value,providing the result,wherein at least the determination of the result takes place only when a plausibility condition is fulfilled.Thus, with respect to a detection system according to the invention, the same advantages result as have already been described with respect to a method according to the invention.It is also conceivable for at least one sensor to be provided, which is designed in particular as a torque sensor, as a rack position sensor, as a rack speed sensor, or as a vehicle speed sensor. In other words, it can be provided that the current rack values to be detected are detected with a specific sensor, which increases the accuracy of the detection.The above object is furthermore achieved by a vehicle according to the invention comprising a detection system according to the invention.This results in the same advantages with respect to a vehicle according to the invention as have already been described with respect to a method according to the invention and / or a detection system according to the invention.The above object is furthermore achieved by a computer program product according to the invention, comprising instructions which, when the program is executed by a computer, in particular by a computing unit of a detection system according to the invention, cause the latter to execute a method according to the invention.Thus, with respect to a computer program product according to the invention, the same advantages result as have already been described with respect to a method according to the invention and / or a detection system according to the invention and / or a vehicle according to the invention.The above object is furthermore achieved by a computer-readable storage medium according to the invention, comprising instructions which, when the program is executed by a computer, in particular by a computing unit of a detection system according to the invention, cause the latter to execute a method according to the invention.This results in the same advantages with respect to a computer-readable storage medium according to the invention as have already been described with respect to a method according to the invention and / or a detection system according to the invention and / or a vehicle according to the invention and / or a computer program product according to the invention.Further advantages, features and details of the invention will become apparent from the following description, in which a plurality of exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination. The schematic figures show: FIG. 1 shows an overview of the method according to the invention, and FIG. 2 shows a detection system according to the invention in connection with a vehicle according to the invention.In the following figures, the identical reference numerals are used for the same technical features, also of different exemplary embodiments.FIG. 1 shows a method 100 according to the invention. Method 100 according to the present invention for detecting an obstacle that lies on a trajectory of a wheel 310 of a vehicle 300 includes:a detection of an input torque 110 from a steering input which at least partially determines the trajectory of the wheel 310, in particular by a computing unit 210 and / or a steering input sensor,a calculation of an expected value 120 of a toothed rack 320, which is designed to set the wheel 310 in accordance with the steering input, for the input torque 110, in particular by the arithmetic unit 210,a detection of a current rack value 130 for the expected value 120 of the rack 320, in particular by the computing unit 210 and / or a rack sensor,a determination of a result of whether an obstacle 400 is located on the trajectory of the wheel 310, based on a comparison of the expected value 120 with the current rack value 130, in particular by the arithmetic unit 210, andproviding the result, in particular by the computing unit 210 and / or an output interface,wherein at least the determination of the result takes place only when a plausibility condition 150 is fulfilled.Overall, the method 100 according to the invention provides the advantage that a detection of an obstacle is provided, which allows a particularly reliable and simple detection of an obstacle and a forwarding of the detection result. The detection of the input torque 110 serves as a starting point, on the basis of which an associated expected value 120 is determined. This provides both a simple and robust way to determine what condition the guidance system should have without obstruction 400. By detecting the current rack value 130, one or more easily determined values are determined that are specific to the actual state of the steering system. The robustness of method 100 is increased in that at least one plausibility condition 150 must be fulfilled in order for the determination to be carried out. This is based on a comparison of the expected state of the steering system with the actual state of the steering system on the basis of the status of the rack 320, which represents a particularly simple and at the same time reliable way of determination. This result 140 is subsequently provided, as a result of which other driving systems and / or persons can also take into account the result 140, such that damage to the vehicle 300 or to the environment can be avoided.Within the scope of the invention, it may be advantageous that an output of the result is provided, in particular via a bus interface 230. In other words, it is also conceivable that the method 100 also comprises transmitting the result 140. The output can be effected at least to a person located in the vehicle 300, in particular a driving person, or to a vehicle system, in particular an assistance system. The output can be at least optically, in particular as a warning symbol, acoustically, in particular as a warning tone, or haptically, in particular as a vibration or impulse at the steering system. The bus interface 230 may be understood as part of a bus system that connects field devices such as sensing elements and actuators in the vehicle 300 for communication with a control unit.Within the scope of the invention, it is conceivable that plausibility condition 150 is determined at least by a comparison of a setpoint value at least for a vehicle speed, a rack speed, a rack position or an assistance level. The set point may include at least one of an upper and a lower set point. Accordingly, at least one set value range can be provided. It can be provided that the (upper) setpoint value for the rack position excludes a range around the end stops of the rack 320. The (lower) setpoint value for the rack speed can prescribe a specific minimum rack speed. It can likewise be provided that a setpoint value specifies a specific support level. It can be provided that all the stated variables determine plausibility condition 150. This offers the advantage that the method 100 is thereby particularly robust with respect to errors and, in addition, fewer or no false positive results 140 are determined.It can be provided within the scope of the invention that a debouncing 160 is provided at least for the detection of an input torque 110 or the detection of a current rack value 130. The debouncing 160 can be implemented at least in hardware, in particular as an RC element in combination with a Schmitt trigger, or in software. The detection accuracy is increased by the debouncing 160, so that the determination of the result becomes more robust and less susceptible to interference overall.It is furthermore conceivable that the input torque 110 comprises at least one hand torque or one motor torque and the detection of the input torque 110 is dependent on a driving operating mode which comprises at least one assistance mode in which an assistance system of the vehicle 300 at least partially takes over the steering, or a manual mode in which the steering of the vehicle 300 is carried out at least partially by a person. In other words, the input torque 110 may be detected for both steering inputs by a person and by a vehicle system, in particular an assist system. This can be effected depending on a driving operating mode. This also leads to the result being determined overall more robust and less susceptible to faults.FIG. 2 finally shows the detection system 200 according to the invention in connection with a vehicle 300 according to the invention. It can be seen that the wheels 310 are connected to a toothed rack 320.The detection system 200 according to the invention for detecting an obstacle which lies on a trajectory of a wheel 310 of a vehicle 300, in particular is designed to carry out a method 100 according to the invention, has a computing unit 210 which is designed to perform a process on the basis of the invention,detecting an input torque 110 from a steering input which at least partially determines the trajectory of the wheel 310,an expected value 120 of a rack 320 configured to set the wheel 310 according to the steering input for the input torque 110,acquiring a current rack value 130 for the expected value 120 of the rack 320,determining a result 140 whether an obstacle 400 is on the trajectory of the wheel 310 based on a comparison of the expected value 120 with the current rack value 130,providing the result,wherein at least the determination of the result takes place only when a plausibility condition 150 is fulfilled.This results in the same advantages with respect to a detection system 200 according to the invention as have already been described with respect to a method 100 according to the invention.It is also conceivable for at least one sensor 220 to be provided, which is designed in particular as a torque sensor 221, as a rack position sensor 222, as a rack speed sensor 223, or as a vehicle speed sensor 224. In other words, it can be provided that the current rack values 130 to be detected are detected with a specific sensor 220, which increases the accuracy of the detection. Furthermore, it can also be provided that the vehicle speed is provided via a bus.The above object is furthermore achieved by a vehicle 300 according to the invention comprising a detection system 200 according to the invention.The foregoing explanation of the embodiments describes the present invention solely by way of examples. Of course, individual features of the embodiments can be freely combined with one another, insofar as technically expedient, without departing from the scope of the present invention.List of reference characters100 Method 110 Input torque 120 Expected value 130 Rack value 140 Result 150 Plausibility condition 160 Debouncing 200 Detection system 210 Computing unit 220 Sensor 221 Torque sensor 222 Rack position sensor 223 Rack speed sensor 224 Vehicle speed sensor 230 Bus interface 300 Vehicle 310 Wheel 320 Rack 400 Obstacle

Claims

Method (100) for detecting an obstacle (400) lying on a trajectory of a wheel (310) of a steering system of a vehicle (300), comprising: - detecting an input torque (110) from a steering input which at least partially determines the trajectory of the wheel (310), - calculating an expected value (120) of a toothed rack (320) on the basis of the input torque (110), wherein the toothed rack (320) is designed to position the wheel (310) in accordance with the steering input, - detecting a current toothed rack value (130) for the expected value (120) of the toothed rack (320), characterized in that the method further comprises: - determining a result (140) whether an obstacle lies on the trajectory of the wheel (310), based on a comparison of the expected value (120) with the current rack value (130), - providing the result (140), wherein at least the determination of the result (140) takes place only if a plausibility condition (150) is fulfilled.Method according to Claim 1, characterized in that an output of the result (140) is provided, in particular via a bus interface (230).Method according to Claim 1 or 2, characterized in that the plausibility condition (150) is determined at least by comparing a setpoint value at least for a vehicle speed, a rack speed, a rack position or an assistance level, wherein the plausibility condition (150) is based on a comparison of the expected state of the steering system with the actual state of the steering system on the basis of the status of the rack (320).Method according to one of the preceding claims, characterized in that a debouncing (160) is provided at least for the detection of an input torque (110) or the detection of a current rack value (130).Method according to one of the preceding claims, characterized in that the input torque (110) comprises at least one manual torque or one engine torque and the detection of the input torque (110) is dependent on a driving operating mode which comprises at least one assistance mode in which an assistance system of the vehicle (300) at least partially takes over the steering, or a manual mode in which the steering of the vehicle (300) is carried out at least partially by a person.Detection system (200) for detecting an obstacle (400) which lies on a trajectory of a wheel (310) of a vehicle (300), in particular is designed to carry out a method according to one of Claims 1 to 5, having a computing unit (210) which is designed to - detect an input torque (110) from a steering input which at least partially determines the trajectory of the wheel (310), - calculate an expected value (120) of a toothed rack (320) which is designed to set the wheel (310) corresponding to the steering input for the input torque, - detect a current toothed rack value (130) for the expected value (120) of the toothed rack (320), - determine a result (140) whether an obstacle lies on the trajectory of the wheel on the basis of a comparison of the expected value (120) with the current toothed rack value (130), providing the result (140), wherein at least the determination of the result (140) is only carried out if a plausibility condition (150) is fulfilled.Detection system (200) according to Claim 6, characterized in that at least one sensor (220) is provided, which is designed in particular as a torque sensor (221), as a rack position sensor (222), as a rack speed sensor (223) or as a vehicle speed sensor (224).A vehicle (300) comprising a sensing system (200) according to any of claims 6 or 7.Computer program product comprising instructions which, when the program is executed by a computer, in particular by a computing unit (210) of a detection system (200) according to Claim 6 or 7, cause the latter to execute a method according to one of Claims 1 to 5.Computer-readable storage medium comprising instructions which, when executed by a computer, in particular by a computing unit (210) of an acquisition system (200) according to claim 6 or 7, cause the latter to execute a method according to one of claims 1 to 5.

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