Method for influencing the movement of a steering handle of a steer-by-wire system in a vehicle

Abstract

A method is proposed for influencing the movement of a steering handle (10) of a vehicle (14), particularly a steer-by-wire system (12) in a motor vehicle, wherein the steer-by-wire system (12) includes at least one feedback actuator (16) for generating steering resistance and / or return torque acting on the steering handle (10), and wherein, in at least one operating state in which the vehicle (14) is stationary and in a passive operating mode different from the normal driving operating mode, the steering resistance and / or return torque of the feedback actuator (16) are set and / or changed by means of a simulation function (18) in response to external forces acting on the steering handle (10), thereby simulating the characteristics of the steering handle (10) related to bore-and / or tire return torque.

Description

Technical Field

[0001] This invention relates to a method for influencing the movement of the steering handle in a steer-by-wire system in a vehicle. Furthermore, this invention relates to a controller having a computing unit for performing such a method, and a vehicle having a computing unit for performing such a method. Background Technology

[0002] Vehicles known from the prior art include conventional steering systems, which have a steering wheel, wheel steering angle adjusters in the form of steering gears, and a steering column for mechanically connecting the steering wheel and the wheel steering angle adjusters. In passive operating mode, that is, operating mode before operation and without steering assistance, such as when ignition is engaged or without mechanical locking of the steering, relatively high torque and / or force are applied to the steering system when the steering wheel is turned and the wheels are turned accordingly. This high torque and / or force occurs particularly due to the bore-and / or tire return torque in the vehicle's stationary state. If the steering wheel is released after deflection, the load on the wheels is reduced, resulting in a predetermined movement of the steering wheel. Here, the steering wheel initially performs a large movement so that it stops with a slight oscillation. This characteristic can be advantageous, for example, when getting into and / or getting out of the vehicle, because the driver can maintain and / or support himself at the steering wheel in this situation.

[0003] Furthermore, vehicles with steer-by-wire systems are known to function without a direct mechanical connection between the steering lever and the wheel being steered, and in this case, steering presets are only electrically transmitted at the steering lever. Such steering systems include a steering input unit with a feedback actuator for generating steering resistance and / or return torque acting on the steering lever, and at least one wheel steering angle adjuster mechanically separated from the steering input unit. In the aforementioned passive operating mode, the feedback actuator is typically deactivated and / or inactive, exhibiting only low, inherent resistance torque. However, the force and / or torque acting in this mode is insufficient to provide support at the steering lever. Even when the feedback actuator is activated, the resulting steering resistance and / or return torque are generally insufficient to achieve this functionality. Summary of the Invention

[0004] The objective of this invention is, in particular, to provide a method for influencing the movement of the steering lever in a steer-by-wire system in a vehicle, the steer-by-wire system having improved performance in terms of the characteristics of the steering lever in a passive operating mode. This objective is achieved through the features of this invention.

[0005] A method is proposed for influencing the movement of the steering handle in a vehicle, particularly a steer-by-wire system, wherein the steer-by-wire system includes at least one feedback actuator for generating steering resistance and / or return torque acting on the steering handle. In at least one operating state, where the vehicle is stationary and in a passive operating mode different from the normal driving mode, the steering resistance and / or return torque of the feedback actuator are set and / or changed by means of a simulation function in response to external forces acting on the steering handle, thereby simulating the characteristics of the steering handle related to bore-and / or tire return torque and advantageously corresponding to those of conventional steering systems. This design can particularly improve the characteristics of the steering handle in passive operating modes by advantageously simulating the characteristics accustomed to by the driver. Specifically, by adapting the steering resistance and / or return torque of the feedback actuator, a corresponding support function can also be provided, thereby allowing the driver to remain and / or be supported at the steering handle, for example, when getting into and / or getting out of the vehicle. Furthermore, it is particularly beneficial to improve the steering feel, especially at the steering handle.

[0006] The steer-by-wire system particularly includes a steering handle. Furthermore, the steer-by-wire system can include additional components and / or structural elements, such as: at least one steering input unit, particularly including a steering handle and / or a feedback actuator; at least one wheel steering angle adjuster, for example configured as a central adjuster or a single-wheel adjuster and advantageously mechanically separated from the steering input unit; at least one controller, particularly configured as a steering controller, specifically configured to electrically couple the steering input unit and the wheel steering angle adjuster; and / or at least one detection unit for detecting and / or monitoring the vehicle's operating state, for detecting and / or monitoring the movement of the steering handle caused by external forces, and / or for detecting and / or monitoring at least one state characteristic parameter related to the vehicle's foundation, from which the state of the foundation can be inferred and thereby the borehole-and / or tire return torque currently acting on the wheels can be calculated. "Feedback actuator" should be understood in particular as an actuator unit that is distinct from the wheel steering angle adjuster and is in direct mechanical connection with the steering handlebar, configured to detect, in particular directly, signals, forces, and / or torques from the steering handlebar and / or transmit them, in particular directly, to the steering handlebar. Specifically, the feedback actuator is at least configured to generate steering resistance and / or reset torque acting on the steering handlebar. Furthermore, the feedback actuator is particularly configured to adapt to the hand torque to be applied to the steering handlebar by the driver and / or the steering feel perceptible through the steering handlebar. For this purpose, the feedback actuator can include at least one electric motor. Furthermore, "passive operating mode" should be understood in particular as an operating mode in which the vehicle is not in the normal driving operating mode, and / or at least one operating function activated in the normal driving operating mode is deactivated and / or disconnected, such as, for example, when the vehicle is stopped and / or parked. Here, passive operating mode specifically corresponds to an operating mode before operation starts and / or before ignition. Preferably, the passive operating mode is a particularly energy-efficient stationary operating mode and / or a particularly energy-efficient ready operating mode. Furthermore, it is advantageous to disconnect at least one traction motor of the vehicle in the passive operating mode. Advantageously, the passive operating mode also differs from a simple start-stop operating mode.

[0007] Furthermore, the vehicle and / or steer-by-wire system particularly includes at least one computing unit configured to execute methods for influencing the movement of the steering lever. Here, "computing unit" should be understood in particular as an electrical and / or electronic unit having an information input terminal, an information processing device, and an information output terminal. Advantageously, the computing unit further includes at least one processor, at least one operating memory, at least one input device and / or output device, at least one operating program, at least one control routine, at least one adjustment routine, at least one calculation routine, and / or at least one evaluation routine. Furthermore, the computing unit particularly includes simulation functionality. Specifically, the computing unit is configured to determine and / or monitor the operating state of the vehicle and / or the movement of the steering lever caused by external forces. Furthermore, the calculation unit is specifically configured to, in an operating state where the vehicle is stationary and in a passive operating mode different from the normal driving operating mode, simulate steering characteristics related to bore-and / or tire return torque, in response to external forces acting on the steering handle, particularly by means of a simulation function and by manipulating the feedback actuator to set and / or change the steering resistance and / or return torque of the feedback actuator. Preferably, the calculation unit is configured to generate an output torque based on the movement of the steering handle caused by external forces acting on it, by means of a simulation function. This output torque can be directly used as a target-preset for the feedback actuator, particularly in the form of a target-motor torque or a target-hand torque, or can be used to obtain a target-preset for the feedback actuator, particularly in the form of a target-motor torque or a target-hand torque. Particularly preferably, in passive operating mode, a simulation function is used to simulate the steering resistance and / or return torque acting on the steering handle, which corresponds to the motion of the wheels in a stationary state of the vehicle and is related to the bore-and / or tire return torque. Preferably, the computing unit is further integrated into the vehicle's controller or preferably integrated into a controller particularly configured as a steering controller. "Setting" should be understood in particular as specifically programmed, designed, and / or equipped. "Object set for a specific function" should be understood in particular as the object satisfying and / or performing that specific function in at least one use state and / or operating state.

[0008] Furthermore, it is proposed that multiple activation conditions be monitored to activate the simulation function, such as, for example, ignition status and / or ignition signal in internal combustion engine vehicles, starting status and / or starting signal in electric vehicles, the closing state of the vehicle doors, the signal of the vehicle key, the vehicle's motion status, the operation status of the vehicle's traction motor, and / or the operation status of the steer-by-wire system, and in this operating state, activation signals are obtained and / or generated, particularly by means of the activation function, based on the activation conditions. Here, the activation signal can be composed, in particular, of a single activation condition or a combination of multiple activation conditions. In particular, the simulation function can be activated at least by the activation signal. Furthermore, the vehicle's onboard electrical network can be advantageously activated and / or enhanced by the activation signal. In particular, the activation signal at least sets the energy supply for activating the feedback actuator. Furthermore, the activation signal can also be advantageously used to obtain the output torque of the simulation function and / or the target preset for the feedback actuator, and / or the activation signal is taken into account when obtaining the output torque of the simulation function and / or the target preset for the feedback actuator. Furthermore, it is particularly preferred that the activation signal be a binary signal. This enables particularly simple and / or precise activation of simulation functions. Furthermore, it advantageously improves operational security.

[0009] Furthermore, it is proposed to generate an output torque, particularly the previously mentioned output torque, based on the motion of the steering handle caused by external forces (especially in the form of steering handle deflection, steering handle velocity, and / or steering handle acceleration) using a simulation function. This output torque is used to determine a target preset for the feedback actuator, wherein the output torque consists of multiple partial torques related to the bore-and / or tire return torque. Here, the bore-and / or tire return torque is characterized, in particular, by hysteresis and spring-damper performance. Specifically, the output torque consists of at least two, preferably at least three, and particularly preferably at least four partial torques. This allows for the simulation of particularly realistic characteristics of the steering handle, especially in passive operating modes.

[0010] If the simulation function includes at least one spring module—by means of which a portion of the torque configured as a spring moment is determined—then it is advantageous to simulate, in particular, the spring properties related to bore-and / or tire return torque, which are transmitted, especially, through the wheels to the steering handle. Preferably, the portion of the torque configured as a spring moment is determined based on an advantageously modified deflection of the steering handle. Furthermore, it is advantageous to determine the portion of the torque configured as a spring moment using a characteristic curve characterizing the spring's properties.

[0011] Furthermore, it is proposed that the steering dynamics of the steering handle and / or the steering dynamics at the steering handle be taken into account when calculating the partial torque configured as a spring torque. Specifically, this is taken into account at least when steering back to the neutral position of the steering handle and / or when reducing the steering handle deflection relative to the neutral position. Preferably, the partial torque configured as a spring torque is modified according to the steering dynamics in this case and preferably reduced, wherein the partial torque configured as a spring torque decreases more rapidly, especially under high steering dynamics and more slowly under low steering dynamics. Thus, the partial torque configured as a spring torque and therefore the output torque of the simulated function can advantageously vary according to the steering dynamics. In particular, a larger change in the partial torque configured as a spring torque can be achieved when the driver suddenly removes their hands from the steering handle after deflecting it, and a smaller change in the partial torque configured as a spring torque can be achieved when the driver actively and slowly turns back after deflecting the steering handle.

[0012] According to another design, the simulation function includes at least one friction module by means of which a portion of the torque configured as a frictional torque is obtained. Preferably, the portion of the torque configured as a frictional torque is obtained based on the movement speed of the steering handle. This is particularly advantageous in simulating the frictional properties associated with drilling and / or tire return torque, which are transmitted to the steering handle, especially through the wheels.

[0013] Furthermore, it is proposed that the simulation function includes at least one damping module by means of which a portion of the torque configured as a damping moment is obtained. Preferably, the portion of the torque configured as a damping moment is obtained based on the speed of movement of the steering handle. Moreover, the damping moment can advantageously depend on the direction and be applied differently, for example, when the spring torque increases and / or decreases. Thus, it is advantageous to simulate, in particular, the damping performance associated with the bore-and / or tire return torque, which is transmitted, especially, through the wheels to the steering handle.

[0014] Furthermore, according to a preferred design, the simulation function includes at least one inertia module by means of which a portion of the torque configured as an inertial moment is obtained. Preferably, the portion of the torque configured as an inertial moment is obtained based on the acceleration of the steering handle. Particularly advantageously, the acceleration is also obtained, and in particular calculated, from the movement speed of the steering handle. Thus, it is advantageous to simulate, in particular, the inertia associated with the bore-and / or tire return torque, which is transmitted to the steering handle, especially through the wheels.

[0015] Furthermore, it is advantageously proposed that the steer-by-wire system includes at least one wheel steering angle adjuster, particularly the aforementioned wheel steering angle adjuster, which is configured, at least in normal driving operation mode, to change the wheel steering angle of at least one wheel according to a steering preset at the steering handle. In the operating state where the vehicle is stationary and in a passive operating mode, the wheel steering angle adjuster can be particularly inactive and / or not operated, so that the wheel steering angle remains unchanged under the action of external forces in this operating state. However, it is preferably proposed that in the operating state where the vehicle is stationary and in a passive operating mode, the wheel steering angle adjuster is active and / or activated, and the wheel steering angle is changed in this operating state according to the action of external forces on the steering handle, particularly changing such that the wheel moves together with the steering handle. This allows for particularly accurate determination of the bore-and / or tire return torque currently acting on the wheel and simulation of the particularly realistic characteristics of the steering handle in the passive operating mode.

[0016] The methods for influencing the movement of the steering handle should not be limited to the usage and implementation described above. In particular, the methods for influencing the movement of the steering handle may have a number different from the number of individual elements, components and units mentioned herein in order to satisfy the functional mode described herein. Attached Figure Description

[0017] Further advantages are apparent from the following description of the accompanying drawings, which illustrate embodiments of the invention.

[0018] in:

[0019] Figures 1a-1b A simplified diagram illustrates a vehicle with a steer-by-wire system;

[0020] Figures 2a-2b An exemplary signal flow diagram is shown for a method of influencing the movement of the steering handle in a steer-by-wire system by means of simulation functionality; and

[0021] Figures 3a-3b A graph showing the different signals associated with vehicle operation is displayed. Detailed Implementation

[0022] Figure 1a and Figure 1b A simplified illustration shows a vehicle 14, exemplarily constructed as a sedan, having multiple wheels 38 and a steer-by-wire system 12. The steer-by-wire system 12 is effectively connected to the wheels 38 and configured to influence the driving direction of the vehicle 14. In this case, the steering preset is transmitted to the wheels 38 only electrically.

[0023] The steer-by-wire system 12 has a wheel steering angle adjuster 40, which is known per se. The wheel steering angle adjuster 40 is exemplarily configured as a central adjuster. The wheel steering angle adjuster 40 has an effective connection with at least two of the wheels 38, particularly the two front wheels, and is configured to convert a steering preset into steering motion of the wheels 38. For this purpose, the wheel steering angle adjuster 40 includes a steering adjustment element 42 exemplarily configured as a rack and a steering actuator 44 acting in conjunction with the steering adjustment element 42, the steering actuator particularly including at least one electric motor (not shown). In principle, the steering system can also, of course, include multiple wheel steering angle adjusters, particularly configured as single-wheel adjusters, or a combination of wheel steering angle adjusters configured as a central adjuster and wheel steering angle adjusters configured as single-wheel adjusters.

[0024] Furthermore, the steer-by-wire system 12 includes a steering input unit 46. The steering input unit 46 is electrically connected to the wheel steering angle adjuster 40. The steering input unit 46 includes a steering handle 10, for example in the form of a steering wheel, for applying hand torque, and a feedback actuator 16, particularly mechanically coupled to the steering handle 10. The feedback actuator 16 is configured to detect, particularly directly, signals, forces, and / or torques from the steering handle 10 and / or transmit them particularly directly to the steering handle 10. In the present case, the feedback actuator 16 is at least configured to generate steering resistance and / or reset torque on the steering handle 10. For this purpose, the feedback actuator 16 includes at least one electric motor (not shown). Alternatively, the steering handle can also be configured as a steering rod and / or a steering ball or something similar. Furthermore, the feedback actuator can also include multiple electric motors.

[0025] Furthermore, the steer-by-wire system 12 has a controller 34. The controller 34 is therefore configured as a steering controller. The controller 34 has an electrical connection to the wheel steering angle adjuster 40. The controller 34 also has an electrical connection to the steering input unit 46. The controller 34 thus couples the wheel steering angle adjuster 40 to the steering input unit 46. The controller 34 is configured to control the operation of the steer-by-wire system 12. The controller 34 is configured to operate the steering actuator 44 based on signals from the steering input unit 46, such as steering presets and / or hand torque. The controller 34 is also configured to operate the feedback actuator 16 based on signals from the wheel steering angle adjuster 40.

[0026] Furthermore, the controller 34 includes a computing unit 36. The computing unit 36 ​​includes at least one processor (not shown), for example, in the form of a microprocessor, and at least one runtime memory (not shown). Additionally, the computing unit 36 ​​includes at least one runtime program stored in the runtime memory, which has at least one control routine, at least one adjustment routine, at least one calculation routine, and at least one evaluation routine. The computing unit 36 ​​includes per se known manipulation functions (not shown) for manipulating the feedback actuator 16 in normal driving operation modes. Furthermore, the computing unit 36 ​​currently includes an analog function 18 for manipulating the feedback actuator 16 (see especially...). Figures 2a-2b Alternatively, the controller can also be different from the steering controller and, for example, be configured as a vehicle central controller.

[0027] Furthermore, vehicle 14 and / or steering-by-wire system 12 may include additional components and / or structural elements, such as, for example, a first detection unit (not shown) for detecting and / or monitoring the operating state of vehicle 14, a second detection unit (not shown) for detecting and / or monitoring the movement of steering handle 10 caused by external forces, and / or a third detection unit (not shown) for detecting and / or monitoring at least one state characteristic parameter related to the foundation of vehicle 14, from which the state of the foundation can be inferred and the current bore-and / or tire return torque acting on wheel 38 can be determined. Additionally, vehicle 14 may include at least one traction motor (not shown) and / or at least one onboard electrical network (not shown). However, in principle, the first, second, and / or third detection units may also be omitted.

[0028] In conventional steering systems with mechanical intervention (durchgriff), in passive operating mode—that is, operating mode before operation begins and without steering assistance—a relatively high torque and / or force is applied to the steering system when the steering wheel is turned and the wheels are turned accordingly. This high torque and / or force arises particularly from the bore-and / or tire return torque when the vehicle is stationary and is transmitted from the wheels to the steering wheel. Here, the performance of the bore-and / or tire return torque can be compared, in particular, with hysteresis and spring-damper performance. If the steering wheel is released after deflection, the load on the wheels is reduced, resulting in the prescribed movement of the steering wheel. This characteristic can also be advantageous, for example, when getting in and / or getting out of the vehicle, because the driver can maintain and / or support himself at the steering wheel in such situations.

[0029] In drive-by-wire steering systems, the feedback actuator is typically disconnected and / or inactive in passive operating mode and has only a small inherent drag torque, where the force and / or torque acting therein is insufficient to provide support at the steering handle. For this reason, according to the present invention, a simulation of the aforementioned characteristics corresponding to conventional steering systems is proposed.

[0030] Next reference Figure 2a and Figure 2b An exemplary method for influencing the movement of the steering handle 10 of the steer-by-wire system 12 is explained below. In this case, the computing unit 36 ​​is configured to implement the method and, in particular, has a simulation function 18 and a computer program with corresponding program code segments. The simulation function 18 can be activated, in particular, in place of the control function, to control the feedback actuator 16 in normal driving operation mode, or advantageously, to be activated in parallel with the control function to control the feedback actuator 16 in normal driving operation mode. Here, the parallel operation of the control function and the simulation function 18 provides an advantage, especially when the simulation function 18 is activated or deactivated.

[0031] According to the invention, in at least one operating state, the vehicle 14 is stationary and in a passive operating mode different from the normal driving operating mode. In this at least one operating state, the steering resistance and / or return torque of the feedback actuator 16 are set and / or changed by means of the simulation function 18 in response to external forces acting on the steering handle 10, thereby simulating the characteristics of the steering handle 10 related to bore-and / or tire return torque. The passive operating mode corresponds to the stationary operating mode and / or ready-to-operate mode in which the traction motor of the vehicle 14 is particularly disconnected.

[0032] Because various operating functions activated in normal driving modes are deactivated and / or cut off in this type of passive operating mode, especially to save energy, it is essential to ensure in the first step that the simulation function 18 is activated and / or is activated. For this purpose, the computing unit 36 ​​includes an activation function 48. Multiple activation conditions are monitored by means of the activation function 48, such as, for example, ignition status and / or ignition signal, start status and / or start signal, the closing state of the vehicle 14's doors, the movement status of the vehicle 14, the operating status of the vehicle 14's traction motor, and / or the operating status of the steer-by-wire system 12. If it is known that the vehicle 14 is stationary and in a passive operating mode, an activation signal 20 is generated by means of the activation function 48 and according to the activation conditions. The activation signal 20 can therefore depend on multiple activation conditions to ensure activation only under desired and / or specified conditions. In this case, the activation signal 20 is a binary signal. The activation signal 20 is at least configured to activate the simulation function 18 and is therefore transmitted to the simulation function 18 (see especially...). Figure 2a Furthermore, it must be ensured during operation that the feedback actuator 16 is activated within a relatively short time to provide steering resistance and / or reset torque. For this reason, the activation signal 20 can also advantageously activate and / or increase the energy supply to the vehicle's electrical system and / or the feedback actuator 16. If the wheels 38 move together with the steering handle 10 during operation, the activation signal 20 can also be configured to activate the steering actuator 44. In particular, the activation signal 20 can thus also activate and / or increase the energy supply to the vehicle's electrical system and / or the steering actuator 44. However, in principle, the activation signal can also be constructed as a signal different from the binary signal. Furthermore, it is conceivable that the analog function is kept active in a passive operating mode, thereby allowing the activation of the analog function to be abandoned. Furthermore, it is conceivable that the energy supply to the vehicle's electrical system, the feedback actuator, and / or the steering actuator can be activated by means of a separate activation signal. Furthermore, when the vehicle is stationary and in a passive operating mode, the steering actuator can be inactive and / or not operating, thus, in principle, the steering actuator can be left unactivated.

[0033] Furthermore, in the operating state where the vehicle 14 is stationary and in a passive operating mode, the force applied to the steering handle 10 is monitored, and motion characteristic parameters 50 related to the force applied to the steering handle 10 and the movement of the steering handle 10 are provided. The motion characteristic parameters 50 may include, for example, the deflection of the steering handle 10, the speed of movement of the steering handle 10, and / or the acceleration of the steering handle 10. The motion characteristic parameters 50 are similarly transmitted to the simulation function 18 and used as input parameters for the simulation function 18.

[0034] If the simulation function 18 is active and the force acting on the steering handle 10 and the resulting movement of the steering handle 10 are known, especially by means of the motion characteristic parameter 50, then the simulation function 18 generates an output torque 22 based on the movement of the steering handle 10 caused by the external force. The output torque 22 is used to determine the target preset 24 for the feedback actuator 16.

[0035] Furthermore, in the current case, the activation signal 20 is used to determine the target preset 24 for the feedback actuator 16. For this purpose, the activation signal 20 is first limited by the limiter 52 of the calculation unit 36, thereby generating a modified activation signal 21. Here, the gradient of the activation signal 20 is preferably limited, thus limiting the activation signal 20 and / or the modified activation signal 21 with respect to dynamics. Next, the output torque 22 and the modified activation signal 21 are calculated together by the calculation routine 54 of the calculation unit 36 ​​to obtain the target preset 24 for the feedback actuator 16. Here, the modified activation signal 21 is used in particular to gradually strengthen and / or gradually weaken the target preset 24 for the feedback actuator 16. Alternatively, however, it is also possible to omit using the activation signal and / or the modified activation signal to determine the target preset for the feedback actuator. In this case, the output torque of the analog function can also be used, for example, directly as the target preset for the feedback actuator. In addition, when determining the target preset for the feedback actuator, filters for filtering the output torque and / or target preset of the analog function, and / or limiters for limiting the output torque and / or target preset to the maximum value can also be used.

[0036] Subsequently, in the second step, the calculation unit 36 ​​is configured to determine the steering resistance and / or the return torque to be set according to the target preset 24 and accordingly manipulate the feedback actuator 16. Here, in the current situation, in the operating state where the vehicle 14 is particularly stationary and in a passive operating mode, the steering resistance and / or return torque of the feedback actuator 16 are thus set and / or changed to simulate the characteristics of the steering handle 10 related to the bore and / or tire return torque.

[0037] In the current situation, the output torque 22 of simulation function 18 is also composed of multiple partial torques related to the drilling and / or tire return torque (see in particular). Figure 2b ).

[0038] The simulation function 18 includes a spring module 26, by which a first portion of the torque, configured as a spring torque, is obtained, thereby advantageously mimicking the spring performance related to drilling and / or tire return torque. Here, the first portion of the torque is obtained based on the deflection of the steering handle 10, which is specifically obtained from the motion characteristic parameter 50. In the current case, the first portion of the torque is obtained based on a modified steering wheel angle, wherein a maximum value of the steering wheel angle is limited for modification. Furthermore, the first portion of the torque is obtained using a characteristic curve characterizing the spring characteristics, thereby enabling the setting of linear, decreasing, and / or exponential spring characteristics. Here, the input parameter for the characteristic curve is the modified steering wheel angle. Furthermore, the steering dynamics of the steering handle 10 and / or the steering dynamics at the steering handle 10 are considered when obtaining the first portion of the torque. In the current case, this steering dynamics are considered at least when the steering returns to the neutral position of the steering handle 10 and / or when the deflection of the steering handle 10 is reduced, wherein the first portion of the torque is modified based on the steering dynamics. Here, the first portion of the torque is modified such that it decreases more quickly under high steering dynamics and decreases more slowly under low steering dynamics. Thus, when the driver suddenly removes their hand from the steering handle 10 after yawing it, a larger modification of the first portion of the torque can be advantageously achieved, and when the driver actively and slowly turns back after yawing it, a smaller modification of the first portion of the torque can be advantageously achieved. Alternatively or additionally, steering dynamics can also be considered when yawing the steering handle, that is, when increasing the steering handle deflection. Furthermore, it is conceivable to abandon the use of characteristic curves and use other mathematical relationships to generate the desired spring characteristics.

[0039] Furthermore, the simulation function 18 includes a friction module 28, by means of which a second part of the torque, configured as a frictional torque, is obtained, thereby advantageously mimicking the frictional performance related to drilling and / or tire return torque. Here, the second part of the torque is obtained based on the movement speed of the steering handle 10 (in the present case, particularly in the form of steering angular velocity), which is obtained in particular from the motion characteristic parameter 50. Here, in the present case, a hysteresis torque is generated based on the movement speed of the steering handle 10 through a reinforcement factor, wherein the reinforcement factor is in particular pre-defined by a dynamic. Furthermore, the hysteresis torque used to form the second part of the torque can be modified by means of low-pass filtering and / or saturation. Furthermore, it is suitable that the movement speed of the steering handle 10 is initially filtered and / or noise is eliminated through dead zones. As an alternative or additional solution, the frictional performance of the chassis or chassis characteristics can also be mimicked by means of the friction module.

[0040] Furthermore, the simulation function 18 includes a damping module 30, by means of which a third portion of the torque, configured as a damping torque, is obtained, thereby advantageously mimicking the damping performance related to the bore-and / or tire return torque. Here, the third portion of the torque is obtained based on the movement speed of the steering handle 10 (in the present case, particularly in the form of steering angular velocity), which is obtained specifically from the motion characteristic parameter 50. In the present case, the third portion of the torque is obtained by multiplying the movement speed of the steering handle 10 by another enhancement factor, wherein, as an additional scheme, filtering and / or limiting can be performed. Furthermore, enhancement and / or gradual strengthening can be achieved based on the movement speed of the steering handle 10. Moreover, the third portion of the torque can be applied differently depending on the direction, for example, in rising and / or falling spring torques.

[0041] Furthermore, the simulation function 18 includes an inertia module 32, by means of which a fourth part of the torque, constructed as an inertial torque, is obtained, thereby advantageously mimicking the inertia associated with drilling and / or tire return torque. Here, the fourth part of the torque is obtained based on the acceleration of the steering handle 10 (in the present case, particularly in the form of steering wheel angle acceleration). In the present case, the acceleration of the steering handle 10 is obtained from the movement speed of the steering handle 10, which is obtained particularly from the motion characteristic parameter 50. For this purpose, the movement speed of the steering handle 10 is differentiated with respect to time and filtered using a filter, advantageously a second-order low-pass filter. The fourth part of the torque is then obtained by multiplying the acceleration of the steering handle 10 by an applied and / or applicable inertia factor, wherein filtering and / or limiting can be performed as an additional scheme. Furthermore, the acceleration of the steering handle 10 can be strengthened and / or gradually increased. Alternatively or additionally, the frictional properties of the chassis, or chassis characteristics, can also be mimicked by means of the inertia module.

[0042] In principle, it is also conceivable to abandon the spring module, friction module, damping module, and / or inertia module, and therefore abandon some torques that are constructed as spring torque, friction torque, damping torque, and / or inertia torque. In particular, the output torque of the simulation function can also include each torque in this respect.

[0043] at last, Figure 3a and Figure 3b An exemplary graph is shown showing the different signals used to influence the movement of the steering handle 10.

[0044] exist Figure 3aIn the diagram, the vertical axis 56 is constructed as a parametric axis. Time is shown on the horizontal axis 58. Curve 60 shows the temporal trajectory of the activation signal 20, where the simulation function 18 is activated at time point T1. Curve 62 shows the temporal trajectory of the deflection of the steering handle 10. In the current case, curve 62 shows an exemplary sinusoidal trajectory of the steering wheel angle. Curve 64 shows the temporal trajectory of the modified steering wheel angle, where a maximum value of the steering wheel angle is defined. Here, the modified steering wheel angle can be defined, for example, to a range of 15°, thus being configured such that the first portion of the spring torque reaches its maximum value at a range of 15°. The modified steering wheel angle begins to form at zero at time point T1 and initially corresponds to the actual steering wheel angle trajectory. The maximum value is reached at time point T2 and then maintained. At time point T3, the direction of the actual steering wheel angle changes, whereby the modified steering wheel angle is also revoked at the same time point. Therefore, when the driver deflects beyond the maximum value, the absolute zero point of the spring's starting point changes.

[0045] exist Figure 3b In the diagram, another vertical axis 66 is constructed as a parametric axis. Time is represented on another horizontal axis 68. Curve 70 shows the time trajectory of the first portion of the torque, constructed as a spring torque, without considering steering dynamics. Curve 72 shows the time trajectory of the first portion of the torque, constructed as a spring torque, with consideration of steering dynamics. When the steering handle 10 is deflected, that is, when the deflection of the steering handle 10 is increased, steering dynamics are not considered, and thus curves 70 and 72 are identical. Conversely, when the steering returns to the neutral position of the steering handle 10 and / or when the deflection of the steering handle 10 is decreased, steering dynamics are considered, wherein the first portion of the torque is reduced according to steering dynamics, and thus curve 72 extends below curve 70.

Claims

1. A method for influencing the movement of a steering handle (10) in a steer-by-wire system (12) in a vehicle (14), wherein, The steer-by-wire system (12) includes at least one feedback actuator (16) for generating steering resistance and / or return torque acting on the steering handle (10), and wherein, in at least one operating state in which the vehicle (14) is stationary and in a passive operating mode different from the normal driving operating mode, the steering resistance and / or return torque of the feedback actuator (16) is set and / or changed by means of a simulation function (18) in response to external forces acting on the steering handle (10), thereby simulating the characteristics of the steering handle (10) related to bore return torque and / or tire return torque.

2. The method according to claim 1, characterized in that, In order to activate the simulation function (18), multiple activation conditions are monitored, and an activation signal (20) is obtained and / or generated based on the activation conditions in the running state.

3. The method according to claim 1 or 2, characterized in that, By means of the simulation function (18), an output torque (22) is generated based on the motion of the steering handle (10) caused by the external force, the output torque being used to determine a target preset (24) for the feedback actuator (16), wherein the output torque (22) consists of multiple partial torques related to the borehole reset torque and / or tire reset torque.

4. The method according to claim 3, characterized in that, The simulation function (18) includes at least one spring module (26) by means of which a portion of the torque is constructed as a spring torque.

5. The method according to claim 4, characterized in that, The partial torque configured as a spring torque is determined based on the deflection of the steering handle (10).

6. The method according to claim 4 or 5, characterized in that, The partial torque constructed as spring torque is obtained by using the characteristic curve that characterizes the spring characteristics.

7. The method according to claim 4, characterized in that, When determining the partial torque configured as a spring torque, the steering dynamics of the steering handle (10) and / or the steering dynamics at the steering handle (10) are taken into account.

8. The method according to claim 3, characterized in that, The simulation function (18) includes at least one friction module (28) and / or a damping module (30) to obtain the partial torques configured as frictional torques and / or the partial torques configured as damping torques.

9. The method according to claim 8, characterized in that, The partial torque configured as a frictional torque and / or the partial torque configured as a damping torque are determined based on the movement speed of the steering handle (10).

10. The method according to claim 3, characterized in that, The simulation function (18) includes at least one inertial module (32) by means of which a portion of the torque is constructed as an inertial torque.

11. The method according to claim 10, characterized in that, The partial torque constructed as an inertial torque is determined based on the acceleration of the steering handle (10).

12. The method according to claim 1, characterized in that, The vehicle in question is a motor vehicle.

13. A controller (34) having a computing unit (36) for performing the method according to any one of claims 1 to 12.

14. The controller according to claim 13, characterized in that, The controller is a steering controller.

15. A vehicle (14) having a steer-by-wire system (12) comprising at least one steering handle (10) and at least one feedback actuator (16) for generating steering resistance and / or reset torque acting on the steering handle (10), and the vehicle having a computing unit (36) for performing the method according to any one of claims 1 to 12.

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