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DE-102024210870-A1 - Method for providing a control variable of a control device that characterizes a control signal of a steering actuator of a steering system of a vehicle, a steering system and a vehicle comprising the steering system

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Abstract

The present invention relates to a steering system, a vehicle comprising the steering system and a method for providing an actuating variable (102) to a control device (100) which characterizes a control signal of a steering actuator of the steering system of a vehicle, wherein the vehicle is operated in a semi-autonomous mode, in particular comprising: Determining a difference (104) between a setpoint (106) and an actual value (108) of a characteristic parameter that characterizes a direction of travel of the vehicle, in particular a position of a rack of the steering system; determining a first adaptation component (110) depending on an actual hand torque (112) and the difference (104) by means of a first controller (116) included by the control device (100); determining a setpoint hand torque (114) depending on the first adaptation component (110) and the difference (104); providing the manipulated variable (102), wherein the manipulated variable (102) is determined depending on the setpoint hand torque (114) and the actual hand torque (112) by a second controller (118) included by the control device (100).

Inventors

  • Marcel Niess
  • Edgar Rot
  • Claus-Dieter Mueller
  • Marianna Salaris
  • Alexander Cziriak
  • Hemanth Kumar Govindarajulu
  • Dominik Erdmann
  • Frank Wuechner
  • Kamrul Huda
  • Hannes Jochim
  • Rohan Narkhede
  • Deepak Devendran
  • Marian Eirich

Assignees

  • Robert Bosch Gesellschaft mit beschränkter Haftung

Dates

Publication Date
20260513
Application Date
20241113

Claims (10)

  1. A method (200) for providing a manipulated variable (102) to a control device (100) that characterizes a control signal of a steering actuator (302) of a steering system (300) of a vehicle (400), wherein the vehicle (400) is operated, in particular, in a semi-autonomous mode, comprising: - Determining (202) a difference (104) between a setpoint (106) and an actual value (108) of a characteristic variable that characterizes a direction of travel of the vehicle (400), in particular a position of a rack (304) of the steering system (300); - Determining (204) a first adaptation component (110) depending on an actual hand torque (112) and the difference (104) by means of a first controller (116) included by the control device (100); - Determining (206) a target manual torque (114) depending on the first adaptation component (110) and the difference quantity (104); Providing (208) the manipulated variable (102), wherein the manipulated variable (102) is determined by a second controller (118) encompassed by the control device (100) depending on the target manual torque (114) and the actual manual torque (112).
  2. The procedure (200) according to Claim 1 , wherein the first controller (116) comprises a plurality (120) of sub-controllers, wherein the plurality (120) of sub-controllers are in particular provided sequentially, wherein the first adaptation component (110) is determined by means of the plurality (120) of sub-controllers (204).
  3. The procedure (200) according to Claim 2 , wherein the first controller (116) comprises a first sub-controller (122) by means of which a first manipulated variable (130) in the form of a dynamic variable of the characteristic parameter, in particular a setpoint speed of the characteristic parameter, for example a setpoint speed of the rack (304), is determined depending on the difference variable (104) and by means of a second sub-controller (124) the adaptation component (110) is determined depending on the first manipulated variable (130).
  4. The procedure (200) according to Claim 3 , wherein the first adaptation component (110) is determined by means of the second sub-controller (124) depending on the actual manual torque (112) and/or an actual speed (128) of the rack.
  5. The procedure (200) according to one of the Claims 3 or 4 , where the first sub-reg The first manipulated variable (130) determined by ler (122) is limited by a predefined limit value (126).
  6. The method (200) according to one of the preceding claims, wherein the target value (106) of the characteristic parameter is limited by a predetermined limit value (132).
  7. The method (200) according to one of the preceding claims, comprising: - Determining (210) a second adaptation component (134) that characterizes a nominal target hand torque, depending on the difference quantity (104) using an evaluation routine (136); wherein the target hand torque (114) is determined (206) depending on the second adaptation component (134).
  8. The method (200) according to any of the preceding claims, comprising at least one of the following steps: - Providing (212) a third adaptation component (138) that characterizes a damping behavior of the steering system (300), in particular a damping torque, for example, dependent on a motion state and/or operating state of the vehicle (400); - Providing (214) a fourth adaptation component (140) that characterizes an inertia of the steering system (300), in particular a moment of inertia, for example, dependent on a motion state and/or operating state of the vehicle (400); - Providing (216) a fifth adaptation component (142) that characterizes a determined steering feel, for example, a steering feel torque; wherein the target hand torque (114) is determined depending on the third adaptation component (138) and/or fourth adaptation component (140) and/or fifth adaptation component (142) (206).
  9. Steering system (300), for example an electrically assisted steering system, in particular an electric power steering system, comprising a steering actuator (302), for example a servo drive, and a control device (100) configured to perform a method (200) according to the Claims 1 until 8 to execute.
  10. Vehicle (400) comprising a steering system (300) according to the Claim 9 , wherein the steering actuator (302) is designed to influence the position of at least one wheel (402) of the vehicle (400) by means of an operative connection, for example a rack and pinion drive (303) with a rack (304), depending on the actuating variable (102).

Description

State of the art The present invention relates to a method for providing a control variable of a control device, which characterizes a control signal of a steering actuator of a steering system of a vehicle, a steering system and a vehicle comprising the steering system. Assisted driving functions are typically based on the rotor position of a steering system actuator. This means that a controller considers any difference in this rotor position to determine a target drive torque, which is then applied to the steering system actuator to reduce the difference between a requested and the actual rotor position, thereby maintaining the requested vehicle trajectory. The performance in achieving the requested rotor position is thus high, ensuring that the position is reached within the required time. However, this approach results in a steering feel that is unpleasant for the driver, which can be described or perceived as dull or artificial, and is not comparable to, for example, the natural steering feel in a non-assisted manual driving mode. Therefore, a steering system is desirable that has a powerful, high-performance position control and also provides an assisted operating mode that offers a natural steering feel for a driver or user of the steering system. Disclosure of the invention This is achieved by a method, a steering system and a vehicle comprising the steering system according to the independent claims. The method for providing a manipulated variable to a control device, which characterizes a control signal of a steering actuator of a vehicle's steering system, wherein the vehicle is operated, in particular, in a semi-autonomous mode, comprises: determining a difference between a setpoint and an actual value of a parameter that characterizes a direction of travel of the vehicle, in particular a position of a rack of the steering system; determining a first adaptation component depending on an actual hand torque and the difference by means of a first controller included in the control device; determining a setpoint hand torque depending on the first adaptation component and the difference; providing the manipulated variable, wherein the manipulated variable is determined by a second controller included in the control device depending on the setpoint hand torque and the actual hand torque. The manipulated variable can, for example, be a drive torque for the steering actuator, by means of which, for example, a rotor position of the steering actuator and thus a direction of travel of the vehicle is influenced. In the following context, the semi-autonomous operating mode includes assisted driving of the vehicle, in which input from a driver is taken into account. Assisted driving includes, for example, a lane keeping assist system for the vehicle. The semi-autonomous operating mode is classified, for example, as SAE L1, SAE L2, or SAE L2+ according to SAE J3016. In this context, the parameter describes a characteristic of the steering system that has a direct influence on the vehicle's direction of travel. This could be, for example, the position of the rack, which is influenced by a variation in the rotor position of the steering actuator. The rack has a mechanical connection to the vehicle's steering elements, such as the wheels. The vehicle's trajectory is influenced by movement of these steering elements. The actual steering torque describes, for example, the torque present at a steering column of the steering system. The target steering torque, accordingly, describes the target torque at the steering column. The actual steering torque is adjusted to the target steering torque using the manipulated variable. The actual steering torque is, for example, detected, determined, or provided. The first adaptation component improves the performance and control behavior of the manipulated variable or control signal, thereby making the steering system more dynamic. Furthermore, the actual hand torque is taken into account when determining the adaptation component, reflecting, for example, the driver's influence or interaction with the steering system, thus improving the steering feel and making it more natural. In this context, a steering actuator is understood to mean, in particular, an actuator unit, especially an electrically designed one, which has a direct operative connection with the rack and is specifically designed to transmit a steering torque to the rack and thereby influence the direction of travel of the vehicle. For example, the steering actuator is designed to provide a steering torque to assist a hand torque applied by the driver of the vehicle at an input device and/or a steering torque for the direct adjustment of the vehicle's wheels, and thereby, in particular, to provide for the automatic and/or autonomous control of the vehicle's direction of travel. For this purpose, the steering actuator may include at least one electric motor. Furthermore, a control device shall be understood to mean, i