Method for detecting a fault in at least one vehicle component of a motor vehicle that is at least partially autonomously controlled, control device for carrying out such a method, and motor vehicle with such a device

Abstract

The invention relates to a method for detecting a fault in at least one vehicle component (60, 62) of a motor vehicle (10) while the latter is controlled at least semi-autonomously according to a predetermined trajectory tracking control, comprising the steps of: acquiring an actual value (34, 44) of at least one actuator of the motor vehicle (10) which is controlled according to the trajectory tracking control; determining a deviation between the acquired actual value (34, 44) of the actuator and a target value (36, 46) of the actuator predetermined according to the trajectory tracking control; determining the fault of the vehicle component (60, 62) as a function of the determined deviation, wherein the actual value (34, 44) comprises at least a portion of a mechanical vibration detectable by a deflection, wherein the deviation is caused by a mechanical vibration which is caused by the fault of the vehicle component (60, 62).The invention further relates to a control device (20) designed to carry out the method according to the invention, and to a motor vehicle (10) with such a control device (20).

Description

[0001] The present invention relates to a method for detecting a fault in at least one vehicle component of a motor vehicle while the vehicle is being controlled at least semi-autonomously according to a predetermined trajectory tracking control, and to a control device for carrying out such a method. The invention further relates to a motor vehicle with such a control device.

[0002] In conventional vehicles, the driver is usually able to detect faults in the driving system haptically or audibly. In autonomous vehicles, where there is no driver present, or the driver is so decoupled from the driving system that they cannot detect anomalies, new methods for detecting such faults are required.

[0003] Methods and devices for correcting errors in driver assistance systems for motor vehicles are known from the prior art.

[0004] US 2022 / 0250679 A1 concerns a method for controlling a steer-by-wire steering system for improved error detection and correction of steering angle deviations, particularly for slight steering angle deviations between the steering wheel and the steered wheels. For this purpose, the method involves calculating a cumulative deviation as a time integral of the control deviation of the position controller in combination with a reference controller designed redundantly to the position controller.

[0005] CN 117 784 756 A relates to a method and device for diagnosing performance degradation of actuators in ADAS (Advanced Driver Assistance Systems). Actual and predicted driving data, such as dynamics, kinematics, and driving trajectories, are compared to calculate deviations and indices that indicate potential degradation. By analyzing typical driving situations and implementing compensatory measures, the stability and functionality of ADAS systems can be improved, and their operational risks reduced. WO 2018 / 224290 A1 relates to a method for increasing safety in a piloted driving system, which, in the event of deviations between the actual and desired actuator output, deactivates a first controller and replaces it with a second controller.A monitoring unit quickly detects deviations and initiates the change of controllers, thereby compensating for potential software errors in the first controller and increasing the reliability of the system.

[0006] The purpose of the invention is to enable reliable and simple detection of errors and defects in vehicle components of at least partially autonomously controlled motor vehicles.

[0007] This problem is solved by the subject matter of the independent claims. Further possible embodiments of the invention are disclosed in the dependent claims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0008] According to the invention, a method is provided for detecting a fault in at least one vehicle component of a motor vehicle while the vehicle is being controlled at least semi-autonomously according to a predetermined trajectory tracking control system. In a first step, an actual value of at least one actuator of the motor vehicle, which is controlled according to the trajectory tracking control system, is acquired. In a next step, a deviation between the acquired actual value of the actuator and a target value of the actuator specified according to the trajectory tracking control system is determined. In a further step, the fault of the vehicle component is determined as a function of the determined deviation, wherein the actual value includes at least a portion of a mechanical vibration detectable by a deflection, and the deviation is caused by a mechanical vibration resulting from the fault of the vehicle component.

[0009] The invention has the advantage that faults or defects in essential vehicle components that control the trajectory tracking system can be detected relatively easily and reliably. Furthermore, such faults and defects can be identified at an early stage, enabling timely inspection of the components and thus increasing the operational and road safety of the vehicle. For example, repairs can be carried out before safety is compromised, a component fails, or consequential damage occurs.

[0010] Overall, this increases reliability and dependability. Furthermore, the procedure allows for a certain assessment of the severity of a fault or defect, enabling better planning of any inspections or workshop visits.

[0011] Non-limiting examples of motor vehicles within the scope of the invention are: passenger cars, trucks, or agricultural machinery. Non-limiting examples of such passenger cars include: small cars, compact cars, mid-size cars, luxury cars, sport utility vehicles (SUVs), station wagons, sedans, pickup trucks, light commercial vehicles, minibuses, minivans, and the like. A motor vehicle within the scope of the invention may, in particular, be a semi-autonomous motor vehicle according to a Level 3 or Level 4 automation level or a fully autonomous motor vehicle according to a Level 5 automation level. Such a semi-autonomous or fully autonomous motor vehicle within the scope of the invention may, in particular, be a passenger car.

[0012] In this context, the levels of automation for driving motor vehicles can be divided into six levels according to the SAE standard J3016: Level 0 (No Automation): The driver performs all driving functions manually; Level 1 (Driver Assistance): The vehicle assists the driver with either longitudinal or lateral control, but not simultaneously. The driver remains responsible and must be able to intervene at any time; Level 2 (Partial Automation): The system takes over both longitudinal and lateral control in certain situations. The driver must monitor the system and be ready to intervene at any time; Level 3 (Conditional Automation): The vehicle can completely take over the driving task under defined conditions. However, the driver must be able to take control upon request; Level 4 (High Automation): The system completely performs the driving task in certain scenarios without requiring any intervention from the driver.Outside of these scenarios, the driver must take over; Level 5 (Full Automation): The vehicle handles all driving tasks independently under all conditions; a driver is no longer necessary.

[0013] A semi-autonomous motor vehicle within the scope of the invention can therefore be understood as a motor vehicle that has a level of automation corresponding to Level 3 or Level 4. A fully autonomous motor vehicle within the scope of the invention can be understood as a motor vehicle that has a level of automation corresponding to Level 5.

[0014] A trajectory tracking control system within the scope of the invention can be understood as a control method in which the motor vehicle is controlled to follow a predetermined trajectory, i.e., a planned roadway or curve of movement, as precisely as possible, with the vehicle's position, speed, and orientation being continuously adjusted to the target trajectory by minimizing deviations through targeted control of the steering, drive, and brakes. This trajectory tracking control system is typically supported by a Self-Driving System (SDS), which generates and adapts the planned trajectory taking into account environmental perception, vehicle dynamics, and navigation data. Such an SDS typically monitors the Operational Design Domain (ODD), which describes the defined operating conditions of the motor vehicle, such as geographical restrictions, road types, weather conditions, or traffic situations.Within this ODD, the trajectory tracking control typically ensures that the vehicle adheres to the planned route safely and efficiently, while the SDS dynamically reacts to changes in environmental conditions and adjusts the trajectory as needed to avoid exceeding the ODD limits. The invention comprises a control unit designed to perform the method according to the invention. The control unit according to the invention can be part of a Self Driving System (SDS).

[0015] An actuator of a motor vehicle within the scope of the invention can be understood as a technical component or device that converts electrical, hydraulic, or pneumatic signals into mechanical motion or physical actions. Actuators execute targeted control or regulation commands and move or influence vehicle components to enable desired functions such as steering, drive, braking, or comfort systems. Non-limiting examples of such actuators include electric motors or internal combustion engines as part of the drive system, electrically or hydraulically driven motors as servomotors of the steering system, and hydraulic cylinders or actuators as part of the braking and suspension system.

[0016] In this context, an actual value of an actuator can be understood as a quantity that represents the current state or the current physical quantity that the actuator influences or generates. Non-limiting examples of such an actual value include actual position, speed, force, or temperature. With regard to a specific system, non-limiting examples of such actual values ​​of an actuator are: actual value of a steering system (servo motor): current steering angle or steering torque, detectable, for example, by an angle or torque sensor; actual value of a braking system (hydraulic cylinder): current brake pressure, detectable, for example, by a pressure sensor in the brake line; actual value of a drive motor: current speed or torque, detectable, for example, by a speed sensor or torque sensor. The actual value is typically measured or acquired in real time and forms the basis for the regulation or control of the actuator by comparing it with the setpoint.The actual value of an actuator can therefore be understood as a measured quantity that describes the actuator's current state and can be determined in real time by sensors or other acquisition methods. This measurement enables the control and regulation of the actuator by comparison with a setpoint value to compensate for deviations.

[0017] In this context, a setpoint of an actuator can be understood as a target state or quantity that the actuator should achieve, such as a desired position, speed, force, or temperature. The setpoint is typically specified by the control system, for example, a Self-Driving System (SDS), and serves as a reference value against which the current actual value is compared in order to minimize deviations through targeted control measures. In the context of an SDS, the setpoint of an actuator is derived from trajectory planning and the system's decisions. To this end, an SDS typically analyzes the environment, calculates the optimal vehicle movement, and translates this into concrete setpoints for the actuators using trajectory tracking control.Non-restrictive examples of such setpoint values ​​are: Setpoint of a steering system: calculated steering angle for trajectory tracking control, for example defined by a rack position or a rotor position; Setpoint of a drive system: required speed or torque for a desired acceleration; Setpoint of a brake: brake pressure to achieve the planned deceleration.

[0018] The phrase "whereby the actual value includes at least a component of a mechanical oscillation detectable by a displacement" means in this context that, for example, a displacement from a neutral position should also be included, which is not a complete oscillation. This occurs, for instance, when the vehicle is steered from a straight-ahead position into a left turn by the trajectory tracking control via the steering system. This steering movement results in a one-sided displacement, which can be represented in a locus diagram as a hill-like curve and lies exclusively above (or below) the abscissa, but does not yet describe a complete oscillation. This component caused by a pure displacement in one direction should also be recorded.

[0019] A vehicle component within the scope of the invention can be understood as a physical unit within a motor vehicle that performs a specific function or contributes to a vehicle function. Vehicle components typically include mechanical, electrical, electronic, hydraulic, and software-based elements that either operate independently or are integrated into a system to ensure the overall functionality of the vehicle. Non-limiting examples of vehicle components are transmissions, differentials, clutches, driveshafts, cardan shafts, racks, steering columns, steering gears, tie rods, shock absorbers, wheels, wheel bearings, springs, axles, and brakes.

[0020] A deviation within the scope of the invention can be understood as a vibration that is superimposed on the actual value expected based on the target value and is therefore detected as a deviation. In other words, under laboratory conditions, i.e., when all components influencing the actual and target values ​​are fault-free and disturbances, defects, or errors of any kind are excluded, the target and actual values ​​are expected to essentially coincide. A deviation within the scope of the invention refers in particular to a deviation in the form of a mechanical vibration caused by a fault in a vehicle component. Such faults frequently cause mechanical vibrations during driving, which can propagate through several vehicle components that are physically or mechanically connected to one another and may potentially...This can also lead to resonance in vehicle components if the natural frequency of the mechanical vibrations is close to the resonance frequency of the vehicle component in question.

[0021] In one embodiment of the invention, the motor vehicle actuator may comprise at least one steering system actuator, which includes a hydraulically or electrically operated servo motor; and / or at least one drive system actuator, which includes an internal combustion engine or at least one electric motor. This offers the advantage that the actual value can be directly acquired via the aforementioned motors, for example, via sensors integrated therein, such as torque sensors or position or speed sensors, or by analyzing the current and voltage signals that are altered by mechanical vibrations. This eliminates the need for costly installation of additional sensors and allows actual and target values ​​to be acquired directly via the respective actuator.

[0022] In one embodiment of the invention, the defective vehicle component may be a component of the steering system, comprising a wheel nut, a wheel housing, a wheel, a tire, a rim, a brake pad, a brake disc, and combinations thereof. This offers the advantage that defects in vehicle components essential for safe lateral control of the motor vehicle can be detected before they impair driving safety or lead to failures or consequential damage.

[0023] In one embodiment of the invention, the defective vehicle component may be a component of the drive system, comprising a brake disc, a transmission, a driveshaft, a wheel, a tire, a rim, a differential, and combinations thereof. This offers the advantage that defects in vehicle components essential for safe longitudinal guidance of the motor vehicle can be detected before they impair driving safety or lead to failures or consequential damage.

[0024] In one embodiment of the invention, the component of trajectory tracking control can be filtered out when acquiring the actual value. This has the advantage that deviations can be detected more effectively because the signal quality of the deviation is thereby improved, i.e., for example, the signal-to-noise ratio (SNR) is enhanced. This enables a better overall determination of the deviation according to the invention.

[0025] In one embodiment of the invention, it can be provided that, during the acquisition of the actual value, at least a portion not caused by the motor vehicle is filtered out, wherein this portion includes the road surface condition, road surface contamination, weather influences, or combinations thereof. This has the advantage that deviations can be detected more effectively because the signal quality of the deviation is thereby increased, i.e., for example, the signal-to-noise ratio (SNR) is improved. Furthermore, this filters out influences that can typically occur during normal driving operation, which makes the method according to the invention more robust and reliable overall. This enables a better determination of the deviation according to the invention.

[0026] In this context, it may be possible to filter out the component of the trajectory tracking control and / or the at least one component not caused by the vehicle using a high-pass filter and / or a band-pass filter. This has the advantage that a high-pass filter can typically filter out low-frequency components of the trajectory tracking control. Furthermore, using a band-pass filter offers the advantage that both low-frequency and high-frequency vibrations can be specifically filtered out, which, for example, allows for better detection of deviations when driving on cobblestones or rumble strips. A high-pass filter and / or band-pass filter within the scope of the invention can be an adjustable filter, i.e., the filter frequency(ies) can be dynamically adjusted or changed.A high-pass filter and / or band-pass filter within the scope of the invention can also be a non-adjustable filter or fixed filter, i.e., the filter frequency(ies) are fixed and cannot be changed. In particular, a high-pass filter and / or band-pass filter within the scope of the invention can be a non-adjustable filter or fixed filter.

[0027] In this context, it may be possible to include adjusting a filter frequency to the vehicle's speed during the filtering process. This has the advantage that components not caused by the vehicle itself, such as those resulting from driving on cobblestones or rumble strips, can be filtered out particularly precisely and with high degree of clarity.

[0028] In one embodiment of the invention, the deviation can be integrated over a defined period, with the integration being performed mathematically, analytically, or as a summation of discrete individual values. This has the advantage that recording over a certain period allows for the calculation of an average value, which better accounts for rapid fluctuations, noise, or short-term disturbances or outliers in the signals, thus achieving a smoothing effect. The signal-to-noise ratio (SNR) can be improved in this way because statistical errors are averaged out. Furthermore, the calculation of such a time integral also allows for better detection of slow changes.

[0029] In one embodiment of the invention, it can be provided that an error message is issued after a predefined limit is exceeded, wherein the error message is optionally only issued after n times the integration has been performed, wherein the limit is exceeded in at least m cases during the n times the integration has been performed, and wherein n > m.Alternatively or additionally, it may be provided that an error message is issued after only a slight exceedance of a predefined limit by 0.01% or 0.05%, or 0.10% or 0.50%, or 1.00% or 1.50%, or 2.0%, or 4.0%, or 6.0%, or 8.0% or 10.0%, wherein the error message is optionally only issued after n times the integration has been performed, wherein the limit is exceeded in at least m cases during the n times the integration has been performed, and wherein n > m, for example n = 10 and m = 2; or n = 10 and m = 4; or n = 10 and m = 6; or n = 10 and m = 8.

[0030] In one embodiment of the invention, it can be provided that, upon exceeding a predefined threshold, at least one error is output to an error detection device, which forwards the at least one error to an error processing unit. It can be provided that such an error can be categorized, with these categories being based on the severity of the error. For example, it can be provided that, in the case of minor errors, only an error message is output or stored in the on-board diagnostics (OBD) system, and that, in the case of major errors, the vehicle is dispatched to its base station or that the vehicle is instructed to pull over, for example, with its hazard warning lights activated, and send a distress message to the base station.This has the advantage that minor faults do not directly lead to a stop of the vehicle and it is possible to estimate when only a short check is necessary and when a longer stay in the workshop needs to be planned.

[0031] In this context, it can further be provided that the error processing unit forwards the at least one error to the control unit according to the invention, which can be part of a Self Driving System (SDS), and which can also ignore the error based on map data and / or specifications of an Operational Design Domain (ODD). This has the advantage that error messages can be hidden, for example, when the vehicle is driving on an unpaved road, which can lead to false error messages.

[0032] The control device according to the invention is designed to carry out the method according to the invention or possible embodiments of the method according to the invention. The control device can be part of a Self Driving System (SDS).

[0033] The motor vehicle according to the invention comprises the control device according to the invention or possible embodiments of the control device according to the invention.

[0034] Further features of the invention may become apparent from the following description of the figures and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0035] The drawing shows in: Fig. 1 A schematic representation of a motor vehicle with a control unit, a data carrier with map data and an operational design domain, a steering system comprising a servo motor as the actuator of the steering system and a drive system comprising an electric motor as the actuator of the drive system; furthermore, two tie rods and two drive shafts are shown as part of the steering and drive systems, respectively; furthermore, four wheels of the motor vehicle are shown, the front wheels of which are part of the vehicle components according to the invention; Fig. 2 A schematic representation of the process flow starting with the recording of actual value and target value up to the integration of a deviation, the evaluation of which generates an error status, showing the control unit, the Operational Design Domain (ODD), the data carrier with map data, a high-pass filter, an integrator, an error detection device and an error processing unit;

[0036] Identical or functionally equivalent elements are marked with the same reference symbols in the figures.

[0037] A motor vehicle 10 is shown in a schematic representation in Fig. Figure 1 shows the motor vehicle 10, which includes a control unit 20, which can be part of a Self Driving System (SDS). Also shown are an Operational Design Domain (ODD) 24 and a data carrier with map data 26. Furthermore, a steering system 30, a drive system 40, two tie rods 52, 54, two front drive shafts 56, 58, and two driven and steered front wheels 60, 62 are shown. The steering system 30 includes an electrically operated servo motor 32 as an actuator. The drive system 40 includes an electric motor 42 as an actuator. The double arrow on the left tie rod 52, which is moved by the servo motor 32, is intended to indicate a steering movement possible in both directions for the lateral guidance of the motor vehicle 10.The rotating arrows on the right driveshaft 58, which is driven by the electric motor 42, indicate that the driveshafts 56, 58 rotate and transmit this rotation to the front wheels 60, 62 to guide the vehicle 10 longitudinally. It is assumed that the vehicle 10 is in motion and describing a left turn, as indicated by the leftward position of the front wheels 60, 62.

[0038] A schematic representation of the procedure is shown in Fig.Figure 2 shows the schematic diagram comprising the control unit 20, the Operational Design Domain (ODD) 24, and the data carrier containing map data 26. The procedure is carried out by the control unit 20. The control unit 20 can interact with the ODD 24, checking the defined operating conditions. The control unit 20 also accesses the map data 26. The schematic diagram also shows the acquisition of an actual value 34 from the servo motor 32, an actual value 44 from the electric motor 42, a setpoint value 36 from the servo motor 32, and a setpoint value 46 from the electric motor 42. A high-pass filter 70 and an integrator 80a, 80b with a timer 82 are also shown schematically. Furthermore, an error detection device 90 and an error processing unit 92 are shown.

[0039] In a first process step, an actual value 34 is acquired from the servomotor 32 of the steering system 30 and an actual value 44 from the electric motor 42 of the drive system 40 of the vehicle 10, whereby the servomotor 32 and the electric motor 42 are controlled by the trajectory tracking control. The actual value 34 of the servomotor 32, i.e., the current steering angle or the steering deflection, can be acquired, for example, via an angle sensor, and the actual value 44 of the electric motor 42, i.e., the current rotational speed, can be acquired, for example, via a rotational speed sensor.

[0040] When recording the actual values ​​34 and 44, the component of the aforementioned trajectory tracking control is filtered out. In the case of actual value 34, the trajectory tracking control causes a leftward steering movement while negotiating the left-hand curve. This steering movement results in a one-sided deflection, which can be represented as a hill-like curve in a locus diagram and lies exclusively above (or below) the abscissa. A leftward steering movement starting from the neutral position, followed by a rightward steering movement, after which the steering returns to the neutral position, would, however, describe a complete oscillation. The deflection generated by the steering input can be essentially filtered out using the high-pass filter 70.In the case of the actual value 44, the trajectory tracking control causes the rotor of the electric motor 42 to rotate, which in turn sets the front wheels 60, 62 into rotation and moves the vehicle 10. The change in the rotor's angular position over time can be represented as a sinusoidal oscillation and visualized in a position-time diagram. This sinusoidal oscillation is also filtered out by the high-pass filter 70.

[0041] When recording the actual values ​​34, 44, at least a portion of mechanical vibrations is additionally filtered out, which is not caused by the motor vehicle 10, but for example by the condition of the road surface on which the motor vehicle 10 is traveling. Due to the mechanical connection that exists between the front wheels 60, 62 and the servo motor 32 or electric motor 44, this portion can be detected in both the steering system 30 and the drive system 40, and has an effect there.

[0042] For example, if the vehicle 10 travels at a speed of 100 km / h on a highway constructed of 25 m long concrete slabs, a periodic vibration with a frequency of approximately 1 Hz is generated by driving over the joints. Verification that the vehicle 10 is on such a slab highway can be carried out by the control unit 20 accessing the map data 26 and by the interaction of the control unit 20 with the ODD 24. The low-frequency vibration is filtered out by the high-pass filter 70 with a correspondingly set filter frequency. Furthermore, the filter frequency is adapted to the speed of the vehicle (10), which allows the filter frequency to be defined with particular precision in order to enable the precise filtering out of the vibrations caused by driving on the slab highway.

[0043] In the next procedural step, a deviation is determined between the recorded actual value 34 and the target value 36 of the servomotor 32 or between the actual value 44 and the target value 46 of the electricmotor 42.

[0044] A first deviation is caused by a mechanical vibration resulting from a defect in the left front wheel 60, which exhibits an imbalance. This imbalance causes a periodic vibration of a comparatively high frequency, which is schematically indicated by the jagged signals in the integrator 80a. Because the left front wheel 60 is connected to the steering gear via the left tie rod 52, which in turn is connected to the servo motor 32 via the rack, the mechanical vibration can propagate through these components to the servo motor 32 and be detected there, for example, by a steering angle sensor that can measure the steering angle position or movement.Because the high-pass filter 70 has essentially filtered out the component of trajectory tracking control and the component of mechanical vibrations caused by driving over the joints of the slab highway, as described above, the actual value 34 essentially only shows the mechanical vibration caused by the imbalance of the left front wheel 60.

[0045] Another deviation is caused by a mechanical vibration resulting from a damaged tire tread on the right front wheel 62. The damaged tire tread causes a high-frequency mechanical vibration whose frequency is higher than that of the electric motor 42. This vibration can be represented similarly to the schematic representation in the integrator 80a. Because the right front wheel 62 is connected to the transmission via the right driveshaft 58, which in turn is connected to the electric motor 42, the mechanical vibration can propagate through these components to the electric motor 42 and be detected there, for example, by a speed sensor. The actual value 44, before filtering by the high-pass filter 70, contains the component of the trajectory tracking control resulting from driving the left turn and the component of the periodic vibration resulting from driving on the flat highway.Furthermore, the actual value 44 includes the component resulting from the damaged tire tread of the right front wheel 62. The actual value 44 was cleaned using the high-pass filter 70, so that the component of the trajectory tracking control and the component caused by the flat highway were eliminated, leaving only the vibration caused by the damaged tire tread of the right front wheel 62.

[0046] In the next step, the error of the vehicle component is determined as a function of the measured deviation using integrator 80a and timer 82. For this purpose, the deviation in the actual value 34 or the actual value 44 is integrated over a defined period of, for example, 5 seconds [s]. The integration is performed here in the form of a summation of discrete individual values, i.e., the spikes of the curve shown in schematic diagram 80a. This allows statistically induced fluctuations to be averaged out. The integration is repeated five times, with the limit being exceeded three times, as indicated by the dashed line in the schematically drawn integrator 80b. The schematic diagrams 80a and 80b are intended to apply to both of the aforementioned deviations in order to illustrate the operating principle. However, actual deviations may have a different curve shape than that shown in integrator 80a or 80b.80b. After the limit value is exceeded, the error is output to an error detection device 90, which forwards the error to the error processing unit 92. The error processing unit 92 forwards the error to the control unit 20, as indicated by the arrow from the error processing unit 92 to the control unit 20. The control unit 20 can also ignore the error based on the map data 24 and the specifications of the ODD 26, as indicated by the arrow emanating from the control unit 20 and ending at the error processing unit 92.This can occur, for example, if the control unit 20 has detected, based on the map data 26, that the vehicle 10 is driving on cobblestones, and this portion has either not been filtered out or can only be filtered out poorly due to the very rough nature of the cobblestones and the resulting high inaccuracy of the measurement. This helps to avoid false error messages. Reference symbol list 10 motor vehicle 20 Control unit 24 Operational Design Domain (ODD) 26 map data 30 Steering system 32 servo motor 34 Actual value servo motor 36 Setpoint servo motor 40 Drive system 42 Electric motor 44 Actual value electric motor 46 Setpoint electric motor 52 Tie rod (left) 54 Tie rod (right) 56 Drive shaft (left) 58 Drive shaft (right) 60 Front wheel (left) 62 Front wheel (right) 70 high-pass filters 80a Integrator (representation of summation of individual values) 80b Integrator (Representation Evaluation Limit Value) 82 Timer 90 Fault detection device 92 Error processing unit QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 2022 / 0250679 A1

[0004] CN 117 784 756 A

[0005] WO 2018 / 224290 A1

[0005]

Claims

[1] Method for detecting a fault in at least one vehicle component (60, 62) of a motor vehicle (10) while the latter is being controlled at least semi-autonomously according to a predetermined trajectory following control, comprising the steps - Recording an actual value (34, 44) of at least one actuator of the motor vehicle (10) which is controlled according to the trajectory following control; - Determining a deviation between the recorded actual value (34, 44) of the actuator and a target value (36, 46) of the actuator specified according to the trajectory sequence control; - Determining the fault of the vehicle component (60, 62) as a function of the determined deviation, wherein the actual value (34, 44) includes at least a portion of a mechanical vibration detectable by a deflection, wherein the deviation is caused by a mechanical vibration which is caused by the fault of the vehicle component (60, 62). [2] Method according to claim 1, wherein the actuator of the motor vehicle (10) is controlled according to the trajectory following control - comprises at least one actuator of the steering system (30), which includes a hydraulically or electrically operated servo motor (32); and / or - includes at least one actuator of the drive system (40), which includes an internal combustion engine or at least an electric motor (42). [3] Method according to any of the preceding claims, wherein the defective vehicle component (60, 62) is a component of the steering system (30) comprising a wheel nut, a wheel housing, a wheel (60, 62), a tire, a rim, a wheel bearing, a brake pad, a brake disc, and combinations thereof. [4] Method according to any of the preceding claims, wherein the defective vehicle component is a component of the drive system (40) comprising a brake disc, a transmission, a drive shaft (56, 58), a wheel (60, 62), a tire, a rim, a wheel bearing, a differential, and combinations thereof. [5] Method according to one of the preceding claims, wherein the proportion of trajectory following control is filtered out when recording the actual value (34, 44). [6] Method according to one of the preceding claims, wherein, when recording the actual value (34, 44), at least a proportion is filtered out which is not caused by the motor vehicle (10), wherein this proportion includes the road surface condition, road surface soiling, weather influences, or combinations thereof. [7] Method according to claim 5 or 6, wherein the filtering out of the component of the trajectory following control and / or the at least one component not caused by the motor vehicle (10) is carried out by means of a high-pass filter (70) and / or band-pass filter. [8] Method according to any one of claims 5 to 7, wherein the filtering out comprises adapting a filter frequency to the speed of the motor vehicle (10). [9] Method according to any of the preceding claims, wherein the deviation is integrated over a defined period of time and wherein the integration is carried out in mathematical, analytical form or in the form of a summation of discrete individual values. [10] Control device (20) designed to perform a method according to any of the preceding claims.

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