Method for operating and / or influencing steering system, steering system and vehicle comprising steering system

Abstract

The invention relates to a steering system, a vehicle comprising the steering system and a method for operating and / or influencing the steering system, the method comprising: providing a first target variable characterizing an exterior of a target adjustment position of a steering actuator; determining a target position for an operating element of the input device as a function of an external first target characteristic, wherein the actual position of the operating element can be influenced by a user; ascertaining an actuation signal for an actuator of the input device as a function of the target position and the actual position of the operating element; ascertaining a second target characteristic variable characterizing the target adjustment position of the steering actuator as a function of the actual position of the operating element; determining a limited target variable, which is limited by at least one predefined limit value, on the basis of the external first target variable and the second target variable; and the target adjustment position of the steering actuator is obtained according to the second target characteristic parameter and the limited target characteristic parameter. The vehicle comprises the steering system.

Description

Technical Field

[0001] The present invention relates to a method for operating and / or influencing a steering system, a steering system, and a vehicle including said steering system. Background Technology

[0002] In driver assistance systems, such as those at SAE L1, SAE L2, or SAE L2+ levels according to SAE J3016, the vehicle utilizes the steering system, particularly steer-by-wire, to detect a target trajectory and determine the corresponding target position of the steering system, such as the steering angle, the road steering angle, and / or the rack position of the rack actuator, to achieve the target trajectory. In the vehicle's assisted operating mode, the steering system identifies changes in the target position, either in cooperation with the vehicle driver or the steering system user, or independently of the driver, in the vehicle's autonomous operating mode or during autonomous driving. Autonomous driving, for example, falls under SAE L3 level or higher according to SAE J3016, while driver assistance, for example, falls under SAE- level below SAE L3. In driver assistance systems at SAE L2 or SAE L1, the driver's input must, for example, have a higher priority than the target trajectory determined by the vehicle.

[0003] Therefore, a steering system is desired that enables precise adjustment of the steering angle and provides reliable feedback to the driver or user, for example, through steering wheel movements that characterize the corresponding steering angle. Furthermore, precise intervention options should be provided for the driver or user. Summary of the Invention

[0004] This is achieved by the method, steering system, and vehicle including the steering system, as claimed in the independent claims.

[0005] A method for operating and / or influencing a steering system, particularly a steer-by-wire system, the method comprising: providing, for example, an external first target characteristic parameter via a controller, the external first target characteristic parameter characterizing a target adjustment position of a steering actuator, particularly a rack actuator; determining a target position for an operating element of an input device based on the external first target characteristic parameter, wherein the operating element is an interface between a user and the steering system, such as a steering handle, wherein the actual position of the operating element can be influenced by the user; determining a control signal for an actuator of the input device based on the target position and the actual position of the operating element, by means of the actuator influencing the actual position of the operating element; determining a second target characteristic parameter based on the actual position of the operating element, the second target characteristic parameter characterizing a target adjustment position of the steering actuator; determining a restricted target characteristic parameter based on the external first and second target characteristic parameters, wherein the restricted target characteristic parameter is restricted by at least one pre-given limit; and determining a target adjustment position for the steering actuator based on the second target characteristic parameter and the restricted target characteristic parameter. By determining the target adjustment position of the steering actuator based on a first external target characteristic parameter, the first external target characteristic parameter has a direct influence on the steering actuator, thereby enabling the steering actuator to be precisely and quickly adjusted to a preset position using the target characteristic parameter. Furthermore, the steering feel perceived by the user can be arbitrarily applied regardless of the influence of the steering actuator and / or chassis. Moreover, only an interface between the steering actuator and the input device is required, thus ensuring a high safety standard for the steering system.

[0006] It can be configured that, when obtaining the restricted target feature parameter, the second target feature parameter is subtracted from the external first target feature parameter, wherein the result of this subtraction operation is restricted by at least one limit value. This improves the efficiency of the method and enables a low-complexity implementation.

[0007] It can be configured that, when determining the target adjustment position, the second target feature parameter and the restricted target feature parameter are added together. This improves the efficiency of the method and enables a low-complexity implementation.

[0008] In one embodiment, the method includes: determining a control signal for an actuator of the steering actuator based on a target adjustment position and an actual adjustment position of the steering actuator, wherein the control signal particularly characterizes the driving torque for the actuator.

[0009] A steering system, particularly a steer-by-wire system, includes a steering actuator and an input device, the input device including an operating element. The steering system is configured to: determine a target position for the operating element of the input device based on a first external target characteristic parameter, provided, for example, by a controller, the first external target characteristic parameter characterizing a target adjustment position of the steering actuator, particularly a rack and pinion actuator, wherein the operating element is an interface between the user and the steering system, such as a steering handle, and wherein the actual position of the operating element can be influenced by the user; determine a control signal for an actuator of the input device based on the target position and the actual position of the operating element, the actuator influencing the actual position of the operating element; determine a second target characteristic parameter based on the actual position of the operating element, the second target characteristic parameter characterizing a target adjustment position of the steering actuator; determine a limited target characteristic parameter based on the first and second external target characteristic parameters, wherein the limited target characteristic parameter is limited by at least one pre-given limit; and determine a target adjustment position for the steering actuator based on the second target characteristic parameter and the limited target characteristic parameter.

[0010] It can be configured such that, when determining the target characteristic parameter to be limited, the steering system is configured to subtract the second target characteristic parameter from the first external target characteristic parameter, and the result of this subtraction operation is limited by at least one limit value.

[0011] What can be configured is that the steering system is designed to add the second target feature parameter and the limited target feature parameter when determining the target adjustment position.

[0012] It can be configured such that the steering system is designed to obtain a control signal for the actuator of the steering actuator based on the target adjustment position and the actual adjustment position of the steering actuator, wherein the control signal particularly characterizes the driving torque for the actuator.

[0013] The vehicle includes a steering system according to the aforementioned embodiment, wherein the steering system is particularly configured to perform the method according to the aforementioned embodiment and particularly to influence the driving trajectory by adjusting at least one wheel of the vehicle, wherein at least one wheel is in effective connection with a steering actuator, for example via a rack. Attached Figure Description

[0014] Further embodiments are derived from the accompanying drawings and the following description. In the drawings: Figure 1 A block diagram of the steering system is shown; Figure 2 Methods for operating and / or influencing the steering system are shown; Figure 3 A vehicle including a steering system is illustrated in the diagram; Figure 4 The time-varying curves of the characteristic parameters of the steering system are shown; Figure 5 The time-varying curves of the characteristic parameters of the steering system are shown. Detailed Implementation

[0015] Figure 1 A steering system 100 is illustrated schematically. The steering system 100 is configured, for example, as a steer-by-wire system, and is used to control a vehicle. The steering system 100 includes a steering actuator 106 and an input device 112, which includes an operating element 110. The operating element 110 can be configured as a handle for operation by a user of the steering system 100. The operating element 110 can be, for example, a steering lever, a steering wheel, or a joystick. The operating element 110 forms an interface between the user and the steering system 100, whereby the user can input information to the steering system 100, such as inputting steering presets for controlling the vehicle.

[0016] The steering system 100 is configured to determine the target position 108 of the operating element 110 for the input device 112 based on an externally provided first target characteristic parameter 102 characterizing the target adjustment position 104 of the steering actuator 106. The externally provided first target characteristic parameter 102 can, for example, be determined by a controller 304 of the vehicle including the steering system 100. Figure 3 The controller 304 can be distributed relative to the steering system 100. An external first target characteristic parameter 102 is read or invoked by the steering system 100 and subsequently processed further. The external first target characteristic parameter 102, for example, characterizes the vehicle target trajectory obtained by the controller within the framework of assisted or autonomous driving of the vehicle. This target trajectory is achieved, for example, through a corresponding target adjustment position 104 of the steering actuator 106.

[0017] The target position 108 is, for example, the rotation angle of the operating element 110 and reflects the current position of the steering actuator 106 in a manner recognizable to the user. The steering actuator 106 is, for example, configured as a rack and pinion actuator.

[0018] The steering system 100 is configured to determine a control signal 116 for an actuator 118 of an input device 112, based on a target position 108 and an actual position 114 of the operating element 110, wherein the actuator affects the actual position 114 of the operating element 110. Therefore, the actual position 114 can be influenced by both the actuator and the user. For example, the control signal 116 can be determined by means of a position adjuster 136.

[0019] The steering system 100 is configured to determine a second target characteristic parameter 120 characterizing the target adjustment position 104 of the steering actuator 106 based on the actual position 114 of the operating element 110. In the current steering system 100, the target adjustment parameter 104 of the steering actuator 106 is influenced by external first target characteristic parameters 102 and / or second target characteristic parameters 120. Here, the external first target characteristic parameter reflects, for example, the influence of assisted driving or autonomous driving usage, and the second characteristic parameter reflects, for example, the influence of the user, such as steering input.

[0020] The steering system 100 is configured to determine a limited target characteristic parameter 122 based on an external first target characteristic parameter 102 and a second target characteristic parameter 120, wherein the limited target characteristic parameter 122 is limited by at least one pre-given limit value 124. The pre-given limit value 124 can be applied to achieve, for example, desired steering characteristics.

[0021] The steering system 100 is configured to determine a target adjustment position 104 for the steering actuator 106 based on a second target characteristic parameter 120 and a limited target characteristic parameter 122. Thus, in determining the target adjustment position 104 of the steering actuator 106, the influence of the user is considered through the second target characteristic parameter 120, and the influence of external first target characteristic parameter 102 is considered, for example, for use in assisted driving or autonomous driving scenarios, and the desired steering characteristics of the steering system 100 are considered through at least one pre-given limit 124. This determination allows for a substantially direct influence on the external first target characteristic parameter 102 via a bypass 138.

[0022] It can be configured that, when determining the restricted target characteristic parameter 122, the steering system 100 subtracts the second target characteristic parameter 120 from the external first target characteristic parameter 102, and limits the result of this subtraction operation by means of at least one limit value 124. The at least one limit value 124, for example, causes the restricted target characteristic parameter 122 to vary within the range defined by the at least one limit value 124. The restricted target characteristic parameter 122 can therefore, for example, be at most, the value of the at least one pre-given limit value 124. The at least one pre-given limit value 124 can, for example, be + / - 1 mm.

[0023] It can be configured that the steering system 100 is configured to add the second target feature parameter 120 and the limited target feature parameter 122 when determining the target adjustment position 104.

[0024] It is possible to configure the steering system 100 to determine a control signal 128 for the actuator 130 of the steering actuator 106 based on the target adjustment position 104 and the actual adjustment position 126 of the steering actuator 106, wherein the control signal 128 particularly characterizes the driving torque for the actuator 130. The actuator 130 can be, for example, an electric drive device. It is also possible to configure the steering actuator 106 as a rack actuator and include a rack 132. In this case, the target adjustment position 104 and the actual position 126 characterize, for example, the position of the rack, particularly in mm.

[0025] At least one limit 124 can influence, for example, the dynamic characteristics, particularly the following characteristics, between the external first target feature parameter 102 and the actual adjustment position 126 or the target adjustment position 104. Furthermore, at least one limit 124 can influence, for example, the delay between the user's steering preset (which affects the actual position 114 of the operating element 110) and the corresponding action of the target adjustment position 104 or the actual adjustment position 126. For example, at least one limit 124 can be variably pre-given according to the motion state of the vehicle and / or the selected vehicle operating mode, or it can be applied as a constant parameter.

[0026] Figure 2 A flowchart of a method 200 for operating and / or influencing, in particular, a steering system 100, such as a steer-by-wire system, is shown. The method includes: providing a first target characteristic parameter 102 external to 202, which characterizes a target adjustment position 104 of a steering actuator 106; and determining, based on the first target characteristic parameter 102 external to 204, a target position 108 of an operating element 110 for an input device 112, wherein the operating element 110 is an interface between the user of the steering system 100 and the steering system 100, and wherein the actual position 114 of the operating element 110 can be influenced by the user. The method 200 can be used, for example, in assisted driving or autonomous driving to operate and / or influence the steering system 100. The method 200 can be used, for example, as a universal interface for operating the steering system 100, regardless of the operating state of the vehicle including the steering system 100.

[0027] The method 200 includes: obtaining 206 an operation signal 116 for the actuator 118 of the input device 112, and influencing the actual position 114 of the operating element 110 by means of the actuator, based on the target position 116 and the actual position 114 of the operating element 110.

[0028] The method 200 includes: determining 208 a second target feature parameter 120 based on the actual position 114 of the operating element 110, the second target feature parameter representing the target adjustment position 104 of the steering actuator 106; and determining 210 a restricted target feature parameter 122 based on an external first target feature parameter 102 and the second target feature parameter 120, wherein the restricted target feature parameter 122 is restricted by at least one pre-given limit value 124.

[0029] The method 200 includes: determining the target adjustment position 104 for the steering actuator 106 based on the second target feature parameter 120 and the restricted target feature parameter 122.

[0030] It can be configured such that, when obtaining the target feature parameter 122 constrained by 210, the second target feature parameter 120 is subtracted from the external first target feature parameter 102, wherein the result of this subtraction operation is constrained by at least one limit value 124.

[0031] What can be set is that when determining the adjustment position 104 of target 212, the second target feature parameter 120 and the restricted target feature parameter 122 are added together.

[0032] It can be configured that the method 200 includes: determining 214 a control signal 128 for the actuator 130 of the steering actuator 106 based on the target adjustment position 104 and the actual adjustment position 126 of the steering actuator 106, wherein the control signal 128 particularly characterizes the driving torque for the actuator 130.

[0033] It is possible to configure the simultaneous execution of multiple steps in the aforementioned steps of method 200.

[0034] Figure 3 A vehicle 300 is shown, which includes a steering system 100 according to the above embodiment, wherein the steering system 100 is particularly configured to perform the method 200 according to the above embodiment, and particularly to influence the driving trajectory of the vehicle 300 by adjusting at least one wheel 302 of the vehicle 300, wherein the at least one wheel 302 is in effective connection with a steering actuator 106, for example, via a rack 132.

[0035] Figure 4 The curves showing the variation of the characteristic parameters of the steering system 100 in the form of position 4 with respect to time 2 are shown. Figure 4The response characteristics of a steering system 100 in one embodiment are shown, in which there is no user intervention or input. A curve showing the change of an external first target characteristic parameter 102 indicates a desired change in the actual adjustment position 126. The target adjustment position 104 immediately follows the external first target characteristic parameter 102, and thus, taking into account the internal inertia of the steering system 100, the actual adjustment position 126 also immediately follows the external first target characteristic parameter. Due to internal inertia, the operating element 110 also follows the external first target characteristic parameter 102 in its position, as reflected by the second target characteristic parameter 120 shown in the curve. The target adjustment position 104 immediately follows the external first target characteristic parameter 102 until the target adjustment position is limited by the limited target characteristic parameter 122 when determined at 212 by means of at least one pre-given limit 124. In the illustrated embodiment, the target adjustment position 104, from the point of limitation, no longer has the same dynamics as the external first target characteristic parameter 102, but instead follows the dynamics of the second target characteristic parameter 120.

[0036] Figure 5 The curves showing the variation of characteristic parameters of the steering system 100 in the form of position 4 with respect to time 2 are displayed. Figure 5 In the illustrated embodiment, user intervention is present, which can be identified based on the change curve of the second target feature parameter 120. Due to at least one limit 124, this input has no effect on the target adjustment signal 104, and consequently, the actual adjustment signal 126 remains unchanged. This results in a delay, adaptable by at least one limit 124, between the user input in the form of the second target feature parameter 120 and the corresponding change in the target adjustment position 104. This delay persists until the limited target feature parameter 122 has exceeded at least one pre-given limit 124.

Claims

1. A method (200) for operating and / or influencing a steering system (100), particularly a steer-by-wire system, said method comprising: - Provide (202) an external first target feature parameter (102) that characterizes the target adjustment position (104) of the steering actuator (106); - The target position (108) of the operating element (110) of the input device (112) is determined (204) based on the first target feature parameter (102) of the external system, wherein the operating element (110) is an interface between the user of the steering system (100) and the steering system (100), wherein the actual position (114) of the operating element (110) can be influenced by the user. - Based on the target position (116) and actual position (114) of the operating element (110), obtain (206) the control signal (116) for the actuator (118) of the input device (112), thereby influencing the actual position (114) of the operating element (110). - The second target feature parameter (120) is obtained (208) based on the actual position (114) of the operating element (110), the second target feature parameter representing the target adjustment position (104) of the steering actuator (106); - The target feature parameter (122) of the constraint is obtained (210) based on the first target feature parameter (102) and the second target feature parameter (120) of the external target feature parameter (102), wherein the target feature parameter (122) of the constraint is constrained by at least one pre-given limit value (124); - The target adjustment position (104) for the steering actuator (106) is determined (212) based on the second target feature parameter (120) and the restricted target feature parameter (122).

2. The method (200) according to claim 1, wherein, When obtaining the target feature parameter (122) of the constraint (210), the second target feature parameter (120) is subtracted from the first target feature parameter (102) of the outside, wherein the result of this subtraction operation is constrained by the at least one limit (124).

3. The method (200) according to any one of the preceding claims, wherein, When determining the target adjustment position (104) mentioned in (212), the second target feature parameter (120) and the restricted target feature parameter (122) are added together.

4. The method (200) according to any one of the preceding claims, the method comprising: - Based on the target adjustment position (104) and the actual adjustment position (126) of the steering actuator (106), a control signal (128) for the actuator (130) of the steering actuator (106) is obtained (214), wherein the control signal (128) particularly characterizes the driving torque for the actuator (130).

5. A steering system (100), particularly a steer-by-wire system, the steering system comprising a steering actuator (106) and an input device (112), the input device comprising an operating element (110), wherein, The steering system (110) is configured to: - The target position (108) of the operating element (110) of the input device (112) is determined (204) according to an external first target feature parameter (102) provided, for example by a controller (304), the external first target feature parameter characterizing the target adjustment position (104) of the steering actuator (106), wherein the operating element (110) is an interface between the user of the steering system (100) and the steering system (100), wherein the actual position (114) of the operating element (110) can be influenced by the user. - Based on the target position (108) and actual position (114) of the operating element (110), obtain (206) the control signal (116) for the actuator (118) of the input device (112), the actuator affecting the actual position (114) of the operating element (110). - The second target feature parameter (120) is obtained (208) based on the actual position (114) of the operating element (110), the second target feature parameter representing the target adjustment position (104) of the steering actuator (106); - The target feature parameter (122) of the constraint is obtained (210) based on the first target feature parameter (102) and the second target feature parameter (120) of the external target feature parameter (102), wherein the target feature parameter (122) of the constraint is constrained by at least one pre-given limit value (124); - The target adjustment position (104) for the steering actuator (106) is determined (212) based on the second target feature parameter (120) and the restricted target feature parameter (122).

6. The steering system (100) according to claim 5, wherein, The steering system (100) is configured to subtract the second target feature parameter (120) from the first target feature parameter (102) of the outside when obtaining the target feature parameter (122) of the constraint (210), and to limit the result of this subtraction operation by means of at least one limit value (124).

7. The steering system (100) according to any one of claims 5 or 6, wherein, The steering system (100) is configured to add the second target feature parameter (120) and the restricted target feature parameter (122) when determining (212) the target adjustment position (104).

8. The steering system (100) according to any one of claims 5 to 7, wherein, The steering system (100) is configured to determine (214) a control signal (128) for the actuator (130) of the steering actuator (106) based on the target adjustment position (104) and the actual adjustment position (126) of the steering actuator (106), wherein the control signal (128) particularly characterizes the driving torque for the actuator (130).

9. A vehicle (300), said vehicle comprising a steering system (100) according to any one of claims 5 to 8, wherein, The steering system (100) is specifically configured to perform the method (200) according to claims 1 to 4, and particularly to influence the driving trajectory by adjusting at least one wheel (302) of the vehicle, wherein the at least one wheel (302) is in effective connection with the steering actuator (106) for example via a rack (132).

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