Steer-by-wire steering system and method
AssigneeZF Automotive Germany GmbH
InventorsPeter Hambloch, Martin Gebing
Life of this patent
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Abstract
A steer-by-wire steering system for a vehicle is described, with a driver-operable control element for steering angle input, an actuating mechanism for setting a wheel setting angle, and with a control unit which is configured, on the basis of a steering angle of the control element and a vehicle speed, to output a map for the setpoint of a position of the actuating mechanism. A defined maximum steering angle is assigned to a maximum wheel setting angle. A method is also described for producing a map for the setpoint of a position of the actuating mechanism in a steer-by-wire steering system.
Claims14
A steer-by-wire steering system for a vehicle, comprising:
- a driver-operable control element for steering angle input,
- an actuating mechanism configured to physically set a wheel setting angle of at least one wheel of the vehicle,
- a control unit operatively coupled to the control element and the actuating mechanism, the control unit being configured to:
- determine, based on a steering angle of the control element and a detected vehicle speed, a speed-dependent map defining a setpoint position of the actuating mechanism,
- wherein the map defines a non-linear relationship between the steering angle and the wheel setting angle such that a defined maximum wheel setting angle of the actuating mechanism independent of vehicle speed,
- wherein, for steering angles exceeding a speed-dependent threshold steering angle, the non-linear relationship is determined by a third-degree polynomial function that includes the defined maximum steering angle and the defined maximum wheel setting angle as influencing parameters, and
- wherein the control unit outputs the set point position to the actuating mechanism to physically move the actuating mechanism and set the wheel setting angle during vehicle operation.
A method for producing a map for a setpoint of a position of an actuating mechanism in a steer-by-wire steering system for a vehicle, comprising:
- detecting a steering angle of a driver-operable control element and a vehicle speed;
- generating, by a control unit, a speed-dependent map defining a relationship between the steering angle and a wheel setting angle of the vehicle,
- wherein the map defines a non-linear relationship such that a defined maximum steering angle is assigned to a defined maximum wheel setting angle independent of vehicle speed, and wherein the non-linear relationship is defined at least in part by a third-degree polynomial function including the defined maximum steering angle and the defined maximum wheel setting angle as influencing parameters;
- and
- outputting by the control unit, a setpoint position of the actuating mechanism based on the map to physically actuate the actuating mechanism and set the wheel setting angle of the vehicle during driving.
Dependencies are inferred from the claim text.