Method for controlling yaw and transversal dynamics in a road vehicle
First Claim
1. Method for controlling the yaw dynamics and lateral dynamics in a road vehicle having one steering device each for the front axle and for the rear axle, and having electrically drivable 8v and δ
-
h steer angle actuators (17 and 18), which are assigned to said axles individually, can be driven via a controller each and which generate from desired/actual value comparisons of variables which are characteristic of the yaw-dynamic and the lateral-dynamic behaviour of the vehicle, for example of the yaw velocity {dot over (Ψ
)} and of a sideslip angle β
, drive signals, required for correcting the controlled variables, for the steer angle actuators, the control loops provided for setting the steer angles δ
v and δ
h being decoupled from one another, and the desired value prescription signals, required for the two control loops, for the control parameters being generated by means of a reference model (28), implemented by an electronic computer, from a processing of at least one output signal, representing the driver'"'"'s wish, from a steering element position sensor (31), and of a sensor output signal characteristic of the operating state of the vehicle, for example a speed sensor, characterized by the following features;
(a) a desired value Svsoll for the lateral force Sv to be built up at the front axle is determined in a control process in the control loop assigned to the front axle;
(b) for this desired value Svsoll, the value of the slip angle, linked to the desired value Svsoll, is determined as desired value α
vsoll from an Sv(α
v) characteristic representing the dependence of the lateral force Sv, to be built up at the front axle, on the slip angle α
v at the front axle, and the absolute value δ
vsoll of the front axle steer angle, which is set by means of the front axle steer angle actuator, is determined in accordance with the relationship (c) a desired value Shsoll for the lateral force Sh to be built up at the rear axle is determined in a control process in accordance with a controller law of the form
in the control loop assigned to the rear axle; and
(d) for this desired value Shsoll of the rear axle lateral force, the value of the slip angle, linked to the desired value Shsoll, is determined as desired value α
hsoll from an Sh(α
h) characteristic, and the absolute value δ
hsoll of the rear axle steer angle which is set by means of the rear axle steer angle actuator is determined in accordance with the relationship
9 Assignments
0 Petitions
Accused Products
Abstract
For the purpose of controlling the yaw dynamics and lateral dynamics in a road vehicle with electrically controlled four-wheel steering, in the case of which the setting of the front axle steer angle δv and of the rear axle steer angle δh is performed by means of mutually decoupled control loops, a desired value Svsoll for the lateral force Sv to be built up at the front axle is determined in the control loop assigned to the front axle and, for this desired value Svsoll, the value of the slip angle, linked to the desired value Svsoll, is determined as desired value αvsoll from an Sv(αv) characteristic representing the dependence of the lateral force Sv, to be built up at the front axle, on the slip angle αv. In the control loop assigned to the rear axle, a desired value Shsoll for the lateral force Sh to be built up at the rear axle is determined in a control process in accordance with a controller law of the form
and, for this desired value Shsoll, the value of the slip angle, linked to the desired value Shsoll, is determined as desired value αhsoll from an Sh(Ch) characteristic. These desired values αvsoll and αhsoll are used to determine the desired values δvsoll and δhsoll of the steer angle, taking account of an estimated value of the sideslip angle β at the centre of gravity of the vehicle, the position of the centre of gravity and measured or estimated values of the yaw velocity {dot over (Ψ)} and of the longitudinal speed vx of the vehicle.
-
Citations
11 Claims
-
1. Method for controlling the yaw dynamics and lateral dynamics in a road vehicle having one steering device each for the front axle and for the rear axle, and having electrically drivable 8v and δ
-
h steer angle actuators (17 and 18), which are assigned to said axles individually, can be driven via a controller each and which generate from desired/actual value comparisons of variables which are characteristic of the yaw-dynamic and the lateral-dynamic behaviour of the vehicle, for example of the yaw velocity {dot over (Ψ
)} and of a sideslip angle β
, drive signals, required for correcting the controlled variables, for the steer angle actuators, the control loops provided for setting the steer angles δ
v and δ
h being decoupled from one another, and the desired value prescription signals, required for the two control loops, for the control parameters being generated by means of a reference model (28), implemented by an electronic computer, from a processing of at least one output signal, representing the driver'"'"'s wish, from a steering element position sensor (31), and of a sensor output signal characteristic of the operating state of the vehicle, for example a speed sensor, characterized by the following features;
(a) a desired value Svsoll for the lateral force Sv to be built up at the front axle is determined in a control process in the control loop assigned to the front axle;
(b) for this desired value Svsoll, the value of the slip angle, linked to the desired value Svsoll, is determined as desired value α
vsoll from an Sv(α
v) characteristic representing the dependence of the lateral force Sv, to be built up at the front axle, on the slip angle α
v at the front axle, and the absolute value δ
vsoll of the front axle steer angle, which is set by means of the front axle steer angle actuator, is determined in accordance with the relationship(c) a desired value Shsoll for the lateral force Sh to be built up at the rear axle is determined in a control process in accordance with a controller law of the form
in the control loop assigned to the rear axle; and
(d) for this desired value Shsoll of the rear axle lateral force, the value of the slip angle, linked to the desired value Shsoll, is determined as desired value α
hsoll from an Sh(α
h) characteristic, and the absolute value δ
hsoll of the rear axle steer angle which is set by means of the rear axle steer angle actuator is determined in accordance with the relationship - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
h steer angle actuators (17 and 18), which are assigned to said axles individually, can be driven via a controller each and which generate from desired/actual value comparisons of variables which are characteristic of the yaw-dynamic and the lateral-dynamic behaviour of the vehicle, for example of the yaw velocity {dot over (Ψ
Specification