Methods for monitoring the steering system

Abstract

The invention takes as its starting point a method for monitoring a steering system (10), in particular a steering system (10) during operation in a vehicle (12), the steering system (10) comprising at least one steering actuator (14), at least one operating signal (16) of the steering actuator (14) being determined and evaluated in order to identify frictional and / or torque break-ins in the steering system (10). It is proposed here that a jerk signal (18) is determined from the operating signal (16) and monitored for changes in order to identify frictional and / or torque break-ins in the steering system (10).

Description

Technical Field

[0001] The present invention starts with a method for monitoring a steering system according to the generic concept of claim 1. Furthermore, the present invention relates to a control device having a computing unit for implementing such a method, a steering system having a computing unit for implementing such a method, and a vehicle having such a steering system.

Background Art

[0002] From the prior art such as German Patent Application Publication No. 102008021849, a method for monitoring a steering system is known, where a belt skip identification device is used for the identification of belt skips and as a result, the identification of frictional coupling disengagement and / or torque disengagement in the steering system. This belt skip identification device identifies belt skips by evaluating the manual moment applied to the steering wheel, the manual angle applied to the steering wheel, and the steering angle of the vehicle wheel or the operating signal of the steering actuator. However, the identification of belt skips based on the captured manual moment leads to problems, for example, in the case of an autonomously driving vehicle or a steer-by-wire steering system. Furthermore, the identification in this case is affected by the system rigidity and may be tampered with in some cases.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The object of the present invention is to provide a method for monitoring a steering system having improved characteristics with respect to efficiency. This object is addressed by the feature portions of claims 1, 10, 11, and 12, while preferred embodiments and variations of the present invention can be read from the dependent claims. [Means for solving the problem]

[0005] Disclosure of the invention The present invention relates in particular to a method for monitoring a steering system in a vehicle during operation, wherein the steering system comprises at least one steering actuator, and the method begins with obtaining and evaluating an operating signal from at least one steering actuator to identify frictional coupling disengagement and / or torque disengagement in the steering system.

[0006] Here, it is proposed that a jerk signal is obtained from the operating signal and monitored for changes in order to identify frictional coupling disengagement and / or torque disengagement in the steering system. Preferably, the jerk signal is obtained and evaluated over time, particularly over the entire monitoring time interval. This evaluation is preferably performed in the time domain. However, the jerk signal can also be evaluated in the frequency domain. This embodiment can improve efficiency, particularly detection efficiency, computational efficiency, and / or cost efficiency. Furthermore, it is possible to achieve robust identification and / or evaluation of frictional coupling disengagement and / or torque disengagement in the steering system, thereby increasing operational reliability. Moreover, it is possible to achieve particularly high flexibility and / or variability.

[0007] Preferably, the vehicle is configured as an automobile and, in particular, includes a steering system and a capture sensor system provided for capturing the operating signal of at least one steering actuator. Furthermore, the steering system may be configured as a conventional steering system, in particular as an electric power steering system, according to the present invention, and may include a mechanical through grip. However, alternatively, the steering system may be configured as a steer-by-wire steering system in which steering settings are transmitted purely electrically to the vehicle wheels. Furthermore, “steering actuator” should be understood to mean an actuator unit configured at least partially electrically and / or electronically, which is provided to provide steering torque and thereby preferably influence the direction of travel of the vehicle. Preferably, the steering actuator is provided to provide steering torque to assist a manual moment applied to the steering wheel, and / or to provide steering torque to automatically and / or autonomously control the direction of travel of the vehicle. For this purpose, the steering actuator may include at least one electric motor.

[0008] Furthermore, the vehicle includes a computing unit provided for implementing a method for monitoring the steering system. “Computing unit” should be understood to mean, in particular, an electrical and / or electronic unit having an information input terminal, an information processing terminal, and an information output terminal. Preferably, the computing unit further includes at least one processor, at least one operating memory, at least one input and / or output means, at least one operating program, at least one control routine, at least one calculation routine, at least one calculation routine, at least one evaluation routine, and / or at least one monitoring routine. In particular, the computing unit is provided for obtaining operating signals, in particular for calling and / or receiving them from the capture sensor system and for evaluation. Furthermore, the computing unit is provided for obtaining jerk signals from the operating signals and monitoring changes in order to identify friction coupling disengagement and / or torque disengagement in the steering system. Preferably, the computing unit is here integrated into the vehicle’s control system, e.g., a central vehicle control system, or a control system for the steering system, in particular in the form of a steering control system. "Frictional coupling disengagement and / or torque disengagement" should be understood, particularly in this context, as meaning sudden relative motion and / or abrupt relative motion between two parts of the steering system that are frictionally and / or geometrically coupled to each other, and / or at least a short-term interruption and / or dissociation of the frictional coupling between those parts. Frictional coupling disengagement and / or torque disengagement, in particular here, leads to at least a short-term loss of steering assistance. Furthermore, frictional coupling disengagement and / or torque disengagement can also essentially lead to an offset in the steering system, particularly in the sensor train and / or servo train of the steering system, and thus can cause, for example, an offset between the measured steering angle and the actual steering angle. Moreover, "jerk signal" should be understood, in particular, as meaning a jerk that appears within the steering system, i.e., a signal that correlates with changes in acceleration over time. "Provided" should be understood, in particular, as meaning specifically programmed, designed, and / or equipped.The fact that an object is provided for a particular function should be understood to mean, in particular, that the object fulfills and / or performs this particular function in at least one use and / or operating state.

[0009] Furthermore, it is proposed that frictional coupling disengagement and / or torque disengagement in the steering system be identified based on at least one signal peak value in the jerk signal, in particular one peak value, thereby enabling particularly simple identification of short-term frictional coupling disengagement and / or torque disengagement in the steering system, such as slippage and / or skipping.

[0010] Alternatively or additionally, it is proposed that frictional coupling disengagement and / or torque disengagement in the steering system be identified when the jerk signal exceeds a particularly defined threshold and / or definable threshold. Additionally, in this case, the duration for which the jerk signal exceeds the threshold can also be monitored and / or determined, thereby preferably enabling estimation of the type of frictional coupling disengagement and / or torque disengagement. In this case, if the jerk signal exceeds the threshold for only a short time, for example, a few milliseconds, it can be estimated that there is a temporary frictional coupling disengagement and / or torque disengagement in the steering system, such as slippage and / or skipping. Conversely, if the jerk signal exceeds the threshold for a long period or permanently, it can be estimated that there is damage to the steering system, such as deformation or breakage.

[0011] Furthermore, it is proposed that a position signal, velocity signal, or acceleration signal of the steering actuator be used as an operating signal, thereby preferably easily obtaining the jerk signal. The position signal may preferably be the rotor position signal of the steering actuator, particularly the electric motor of the steering actuator. The velocity signal may preferably be the rotor velocity signal of the steering actuator, particularly the electric motor of the steering actuator. Furthermore, the acceleration signal may preferably be the rotor acceleration signal of the steering actuator, particularly the electric motor of the steering actuator.

[0012] Preferably, the jerk signal is determined based on the rate of change of the action signal over time and / or using the time derivative of the action signal. Preferably, the position signal from the steering actuator can be used as the action signal, and the jerk signal can be determined, for example, based on the third time derivative of the position signal. However, alternatively, the velocity signal of the steering actuator can be used as the action signal, and the jerk signal can be determined, for example, based on the second time derivative of the velocity signal. Furthermore, the acceleration signal of the steering actuator can be used as the action signal, and the jerk signal can be determined, for example, based on the first time derivative of the acceleration signal. In any case, by using existing signals or callable signals, a particularly advantageous and low-cost solution can be provided.

[0013] Furthermore, frictional coupling disengagement and / or torque disengagement in the steering system correspond to frictional coupling disengagement and / or torque disengagement in the sensor train and / or frictional coupling disengagement and / or torque disengagement in the servo train, thereby enabling variable monitoring and / or comprehensive monitoring of the steering system in particular. The sensor train may correspond, for example, to the steering shaft and / or steering column of the steering system, while the servo train may correspond, in particular, to the steering gear of the steering system.

[0014] Furthermore, frictional coupling disengagement and / or torque disengagement can also be caused by freewheeling, slipping, and / or skipping of any mechanical interface in the steering system. However, according to one embodiment, the steering system is proposed to include at least one traction means acting particularly frictionally and / or shape-coupled, and / or at least one allow ring acting particularly frictionally and / or shape-coupled, wherein frictional coupling disengagement and / or torque disengagement are caused by freewheeling, slipping, and / or skipping of the traction means and / or allow ring. The traction means here in particular may be, for example, part of a connecting gear for connecting a steering actuator to a steering gear, and may be configured particularly as a belt, preferably a toothed belt. The allow ring may be, for example, part of a slip clutch and / or screw gear. This can, in particular, increase the efficiency of the method and allow monitoring of the main causes of frictional coupling disengagement and / or torque disengagement in the steering system.

[0015] Furthermore, it is proposed to use an event counter to identify friction coupling disengagement and / or torque disengagement in the steering system. In particular, in this case, the counter value of the event counter is incremented first by evaluation of the jerk signal, in particular based on the signal peak value and / or anomaly in the jerk signal, and if the counter value of the event counter exceeds a limit value, e.g., 3 or 4, friction coupling disengagement and / or torque disengagement in the steering system is estimated. Subsequently, a system response may be introduced and / or executed, preferably in the form of a security measure. This system response may include, for example, the generation of an instruction message and / or aging of the steering system or vehicle. Particularly preferably, the counter value of the event counter is further reset, in particular to zero, if no signal peak value and / or anomaly appear in the jerk signal within a defined and / or definable time. This can further enhance robustness and / or operational reliability.

[0016] Preferably, when identifying frictional coupling disengagement and / or torque disengagement in the steering system, it is proposed to take into account at least one validation variable, particularly to enhance robustness and / or for validation purposes. Preferably, this validation variable is an operating signal and / or capture signal from the sensor train side, e.g., manual moment and / or steering wheel displacement, and an operating signal and / or capture signal from the servo train side, e.g., torque, rotation angle, rotational speed of the steering actuator, preferably the average value of the rotor rotational speed and / or the acceleration of the steering actuator and / or an operating signal and / or capture signal correlated with the vehicle's running state, e.g., vehicle speed and / or yaw moment. Particularly preferably, when identifying frictional coupling disengagement and / or torque disengagement in the steering system, multiple validation variables, e.g., at least two or at least three validation variables, can be taken into account and / or coupled to each other. This can, in particular, achieve further improvements in robustness.

[0017] A particularly efficient method can be achieved in which the steering system includes at least one traction means in the form of a toothed belt having multiple teeth, and frictional coupling disengagement and / or torque disengagement in the steering system is identified based on signal peak values ​​in a jerk signal, where the number of skipped teeth is estimated and / or determined based on the number of signal peak values ​​in the jerk signal.

[0018] Methods for monitoring the steering system should not be limited to the uses and embodiments described herein. In particular, methods for monitoring the steering system may have a different number of individual elements, parts, and units than those listed herein in order to satisfy the functions described herein.

[0019] Further advantages will become apparent from the description of the drawings below. These drawings illustrate embodiments of the present invention. [Brief explanation of the drawing]

[0020] [Figure 1a] FIG. is a schematic view showing an exemplary vehicle equipped with a steering system. [Figure 1b] FIG. is a schematic view showing an exemplary vehicle equipped with a steering system. [Figure 2] FIG. is a diagram showing various signals for monitoring a steering system. [Figure 3] FIG. is an exemplary flowchart with the main method steps of a method for monitoring a steering system.

DETAILED DESCRIPTION OF THE INVENTION

[0021] Description of Embodiments FIGS. 1a and 1b schematically show an exemplary vehicle 12 configured as a passenger vehicle equipped with a plurality of vehicle wheels 40 and a steering system 10. This steering system 10, in the case of the present invention, particularly has an operative connection with the vehicle wheels 40 configured as front wheels and is provided to influence the driving direction of the vehicle 12. Further, the steering system 10 is configured as an electric power assist steering system and thus has an electric power assist in the form of power steering. However, basically, it is also conceivable to configure the steering system as a hydraulic assist steering system, particularly having a hydraulic power assist. Further, the steering system can basically also be configured as a steer-by-wire steering system.

[0022] In the case of the present invention, the steering system 10 is exemplarily configured as a steering wheel and includes a steering handle 42 for applying a manual moment, and is exemplarily configured as a rack and pinion type steering gear and includes a steering adjustment element 46 and is provided for converting the steering input at the steering handle 42 into the steering movement of the vehicle wheel 40. The steering gear 44 includes a steering shaft 48 for mechanically connecting the steering handle 42 to the steering gear 44 in particular. The steering shaft 48 defines the sensor train 28 of the steering system 10. The steering gear 44 defines the servo train 30 of the steering system 10. Alternatively, the steering handle can also be configured as a steering lever or a steering ball, etc. Furthermore, it is also conceivable to omit the steering handle. Even further, the steering shaft can also connect and / or mechanically separate the steering handle from the steering gear only temporarily, such as in a steer-by-wire steering system.

[0023] Even further, the steering system 10 includes a steering actuator 14. This steering actuator 14 is at least partially electrically and / or electronically configured. The steering actuator 14 has an operative connection with the steering gear 44. The steering actuator 14 is provided for providing a steering torque for assisting the manual moment applied to the steering handle 42 and transmitting it to the steering adjustment element 46. For this purpose, the steering actuator 14 includes an electric motor (not explicitly shown). In the case of the present invention, this electric motor is particularly configured as a permanent magnet synchronous motor and is provided for generating the steering torque. Basically, the steering actuator may also include a plurality of electric motors.

[0024] To connect the steering actuator 14 to the steering gear 44, the steering system 10 further includes a coupling gear 50. In the present invention, this coupling gear 50 is configured as a traction means drive unit and includes at least one traction means 32. The coupling gear 50 is configured here as a belt drive unit and therefore includes a traction means 32 configured as a belt, and in the present invention particularly as a toothed belt. The coupling gear 50 is provided to transmit the steering torque of the steering actuator 14 to the steering gear 44 using the traction means 32. However, alternatively, the coupling gear configured as a traction means drive unit may be configured as a chain drive unit, and / or may include a traction means configured as a flat belt, round belt, V-belt, and / or poly-V-belt. Furthermore, the coupling gear may be configured as a screw gear and / or worm gear. Furthermore, the coupling gear and / or steering system may include a tolerance ring.

[0025] Furthermore, the steering system 10 includes a steering sensor system 52, which is known in itself, located on the steering shaft 48. According to the present invention, this steering sensor system 52 is configured as a torque sensor. The steering sensor system 52 is provided to capture a sensor signal 54 correlated with the operation of the steering wheel 42, in particular the manual moment and / or torque applied to the steering wheel 42. In the present invention, this sensor signal 54 corresponds here to a torsion bar signal. Alternatively, the steering sensor system may be configured as a sensor different from the torque sensor, for example, a rotation angle sensor, and / or a combined torque and rotation angle sensor.

[0026] Furthermore, the steering system 10 includes a capture sensor system 56 assigned to the steering actuator 14. This capture sensor system 56 is configured as a rotor position sensor and is provided to capture at least one operating signal 16 of the steering actuator 14, in particular, in the present invention, the rotor position signal of an electric motor. However, alternatively or additionally, the capture sensor system may be configured as a sensor other than the rotor position sensor, for example, a speed sensor and / or an acceleration sensor.

[0027] Furthermore, the vehicle 12 has a control device 36. This control device 36 is exemplary configured as a steering control device and is therefore part of the steering system 10. The control device 36 has an electrical connection to the steering actuator 14. Furthermore, the control device 36 has an electrical connection to the steering sensor system 52 and the capture sensor system 56. The control device 36 is provided to receive sensor signals 54 from the steering sensor system 52 and operation signals 16 from the capture sensor system 56. Furthermore, the control device 36 is provided for drive control of the steering actuator 14.

[0028] For this purpose, the control device 36 includes a computing unit 38. This computing unit 38 includes, for example, at least one processor in the form of a microprocessor and at least one operating memory. Furthermore, the computing unit 38 includes at least one operating program stored in the operating memory, which has at least one control routine, at least one calculation routine, at least one computation routine, at least one evaluation routine, and at least one monitoring routine. However, it is also conceivable that the control device be configured separately from the steering system. In this case, the vehicle may have a single central control device having, for example, a central computing unit.

[0029] In order to maintain the proper function of the steering system 10, a permanent frictional coupling in the steering system 10 is fundamentally necessary. However, certain driving and / or operating conditions may lead to frictional coupling disengagement and / or torque loss in the steering system 10. However, this type of frictional coupling disengagement and / or torque loss, without sufficiently accurate detection, can lead to driving conditions that pose a critical safety risk.

[0030] For this reason, a method for monitoring the steering system 10 during operation within the vehicle 12 will be described below. In particular, a computing unit 38 is provided to carry out this method and further comprises a computer program having corresponding program code means for this purpose.

[0031] According to the present invention, in order to identify friction coupling disengagement and / or torque disengagement in the steering system 10, at least one operating signal of the steering actuator 14, in particular in this invention, an operating signal 16 captured using the capture sensor system 56, is obtained and evaluated. For this purpose, a jerk signal 18 is generated from the operating signal 16 and its changes are monitored. Friction coupling disengagement and / or torque disengagement in the steering system 10 can be determined here based on at least one signal peak value 20, 22, 24 in the jerk signal 18, or based on the exceedance of a threshold 26 (see Figure 2 in particular). According to the present invention, it is taken advantage of the fact that a very large rotor acceleration is generated during friction coupling disengagement and / or torque disengagement in the steering system 10, and this rotor velocity can be determined by evaluating the corresponding jerk signal 18. However, the jerk signal can also be evaluated in the frequency domain. Furthermore, it is conceivable to monitor and evaluate the gradient of the jerk signal.

[0032] Furthermore, exemplary frictional coupling disengagement and / or torque disengagement corresponds to frictional coupling disengagement and / or torque disengagement in the servo train 30, which may be caused by slippage, slip, and / or skipping of the traction means 32. However, fundamentally, frictional coupling disengagement and / or torque disengagement may also be caused by any other mechanical interface in the steering system 10, such as a perforating ring, which may occur, for example, in the sensor train 28, or in the sensor train 28 and the servo train 30.

[0033] Furthermore, the position signal of the steering actuator 14, particularly the rotor position signal, is used as the operating signal 16, in which case the jerk signal 18 can be determined using the time derivative of the operating signal 16, and in particular, according to the present invention, based on the third time derivative of the operating signal 16. However, alternatively, the velocity signal or acceleration signal of the steering actuator can also be used as the operating signal.

[0034] Furthermore, an event counter can be used to identify friction coupling disengagement and / or torque disengagement in the steering system 10. This event counter may be integrated, for example, into the calculation unit 38. In this case, the counter value of the event counter is incremented first based on the evaluation of the jerk signal 18, in particular based on the signal peak values ​​20, 22, 24 and / or anomalies within the jerk signal 18, and if the counter value of the event counter exceeds a limit value, for example, 3 or 4, friction coupling disengagement and / or torque disengagement in the steering system 10 is estimated. As a result, a system response may then be introduced and / or executed. This system response may include, for example, the generation of an instruction message and / or aging degradation of the steering system 10 or the vehicle 12. However, this type of event counter can basically be omitted. In this case, the corresponding system response may already occur based on one signal peak value and / or the period during which the jerk signal 18 exceeds the threshold 26.

[0035] To further enhance the robustness of this method, at least one additional validation variable 34 can be considered when identifying friction coupling disengagement and / or torque disengagement in the steering system 10 (see Figure 2 in particular). In the present invention, this validation variable 34 is the operating signal and / or acquisition signal from the servo train, more particularly the torque of the steering actuator 14. However, alternatively or additionally, operating signals and / or acquisition signals from the sensor train, such as the sensor signal 54, and / or operating signals and / or acquisition signals correlated with the driving state of the vehicle 12, such as vehicle speed and / or yaw moment, can also be used as validation variables. Furthermore, operating signals and / or acquisition signals from the servo train that are different from the torque of the steering actuator 14, such as the rotation angle and / or rotational speed of the steering actuator 14, preferably the average value of the rotor rotational speed, can be used as validation variables. Moreover, it is also conceivable to basically omit the validation variables altogether.

[0036] Figure 2 shows an illustrative diagram of various signals for monitoring the steering system 10.

[0037] The first vertical axis 58 is configured as a variable axis, and the jerk is [1 / s 3 The units are shown in [s]. The first horizontal axis 60 shows time in [s] units. The first characteristic curve 62 shows the time course of the jerk signal 18. The second vertical axis 64 is configured as a further variable axis and shows torque in [Nm] units. The second horizontal axis 66 also shows time in [s] units. The second characteristic curve 68 shows the time course of the validation test variable 34, or in the case of the present invention, the torque of the steering actuator 14.

[0038] Based on the characteristic curve 62, after approximately 8.5 seconds, the appearance of multiple signal peak values ​​20, 22, and 24 within the jerk signal 18 can be recognized, which characterize frictional coupling disengagement and / or torque disengagement in the steering system 10. When using a traction means 32 in the form of a toothed belt having multiple teeth, the number of skipped teeth can be further estimated based on the number of signal peak values ​​20, 22, and 24 within the jerk signal 18. In the present invention, this means that three teeth of the traction means 32 were skipped.

[0039] Furthermore, the characteristic curve 68 can be used to improve the robustness of the steering system 10 and / or to validate frictional coupling disengagement and / or torque disengagement in the steering system 10. Based on the progression of the validation variable 34, it can be recognized that a drop in torque of the steering actuator 14 occurs immediately before the first signal peak value 20 within the jerk signal 18. This drop in torque of the steering actuator 14 is used as indirect evidence of frictional coupling disengagement and / or torque disengagement in the steering system 10 in relation to the time-series signal peak values ​​20, 22, and 24 within the jerk signal 18.

[0040] Finally, Figure 3 illustrates a flowchart using key method steps to show a method for monitoring the steering system 10.

[0041] In step 70 of the method, the operation signal 16 of the steering actuator 14 is obtained.

[0042] In step 72 of the method, the jerk signal 18 is obtained from the operating signal 16. In the present invention, this is done using the time derivative of the operating signal 16, and in particular, according to the present invention, it is done using the third time derivative of the operating signal 16.

[0043] In step 74 of the method, the jerk signal 18 is monitored and evaluated. In this invention, in particular, it is monitored whether signal peak values ​​20, 22, 24 are present in the jerk signal 18 and / or whether the jerk signal 18 exceeds the threshold 26. If this is the case, friction coupling disengagement and / or torque disengagement in the steering system 10 is estimated, and the process proceeds to step 76 of the method.

[0044] In step 76 of the method, a system response is introduced and / or performed. This system response may include, for example, the generation of an instruction message and / or the deterioration of the steering system 10 or the vehicle 12 due to aging.

[0045] The illustrative flowchart in Figure 3 is intended here solely as an illustrative description of a method for monitoring the steering system 10. In particular, individual method steps can be modified, or additional method steps can be added. For example, an event counter can be used to identify friction coupling disengagement and / or torque disengagement in the steering system 10. Furthermore, a validation variable 34 can be taken into consideration when identifying friction coupling disengagement and / or torque disengagement in the steering system 10.

Claims

1. A method for monitoring a steering system (10) in a vehicle (12) including at least one steering actuator (14) during operation, At least one operating signal (16) of the steering actuator (14) is obtained. A jerk signal (18) is obtained from the aforementioned operating signal (16). A temporary interruption in torque transmission caused by freewheeling, slipping, or skipping between two parts of the steering system (10) that are connected to each other frictionally or geometrically is identified based on a change in the jerk signal (18). A method characterized by the following:

2. The method according to claim 1, wherein a temporary interruption of torque transmission between two parts of the steering system (10) that are frictionally or geometrically connected to each other is identified based on at least one signal peak value (20, 22, 24) in the jerk signal (18), or is identified when the jerk signal (18) exceeds a threshold (26).

3. The method according to claim 1, wherein the position signal, speed signal, or acceleration signal of the steering actuator (14) is used as the operation signal (16).

4. The method according to claim 1, wherein the jerk signal (18) is determined based on the rate of change of the operation signal (16) over time, or is determined using the time derivative of the operation signal (16).

5. The method according to claim 1, wherein a temporary interruption of torque transmission between two components of the steering system (10) that are connected to each other frictionally or geometrically corresponds to a temporary interruption of torque transmission between two components of the sensor train (28) or servo train (30) that are connected to each other frictionally or geometrically.

6. The steering system (10) includes at least one traction means (32), and a temporary interruption of torque transmission between two parts of the steering system (10) that are frictionally or geometrically coupled is caused by freewheeling, slipping, or skipping of the traction means (32), as per claim 1.

7. The steering system (10) includes at least one allow ring, and a temporary interruption of torque transmission between two parts of the steering system (10) that are frictionally or geometrically coupled is caused by free-spinning, slipping, or skipping of the allow ring, according to claim 1.

8. The method according to claim 2, wherein the counter value of an event counter is incremented based on the signal peak values ​​(20, 22, 24) in the jerk signal (18), and a temporary interruption of torque transmission is identified when the counter value of the event counter exceeds a limit value.

9. The method according to claim 1, wherein, when identifying a temporary interruption in torque transmission between two parts of the steering system (10) that are frictionally or geometrically connected to each other, at least one validation variable (34) is taken into consideration, the validation variable (34) being an operating signal and / or acquisition signal on the sensor train side, an operating signal and / or acquisition signal on the servo train side, and / or an operating signal and / or acquisition signal that correlates with the running state of the vehicle (12).

10. The method according to claim 1, wherein the steering system (10) includes at least one traction means (32) in the form of a toothed belt having a plurality of teeth, and a temporary interruption of torque transmission between two mutually shape-coupled parts of the steering system (10) is identified based on signal peak values ​​(20, 22, 24) in the jerk signal (18), and the number of skipped teeth is estimated based on the number of signal peak values ​​(20, 22, 24) in the jerk signal (18).

11. A control device (36) comprising a calculation unit (38) for carrying out the method described in claim 1.

12. A steering system (10) comprising at least one steering actuator (14) and a computing unit (38) for carrying out the method according to claim 1.

13. A vehicle (12) equipped with the steering system (10) according to claim 12.

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