Algorithm for steering angle command to torque command conversion

摘要

A system and method for converting a vehicle steering angle command to a vehicle steering torque command for a vehicle steering system in a vehicle. The method estimates a self-aligning torque that defines the torque that maintains a vehicle steering wheel at a neutral steering position or to a position that makes no slip angle at the road wheel, applies known total steering torque commands to the steering system at a plurality of sample time steps where the known steering torque commands include the self-aligning torque, and measures a vehicle steering angle at each time step. The method then models the steering system of the vehicle using the torque commands, the measured steering angles, a system delay and a plurality of unknown parameters.

主权项

1. A method for converting a vehicle steering angle command to a vehicle steering torque command for a vehicle steering system in a vehicle, said method comprising:
estimating a self-aligning torque that defines the torque that maintains a vehicle steering wheel at an initial steering angle; applying known total steering torque commands to the steering system at a plurality of sample time steps where the known steering torque commands include the self-aligning torque; measuring, using a steering angle sensor, a vehicle steering angle at each time step; and modeling the steering system of the vehicle using the torque commands, the measured steering angles, a system delay and a plurality of steering system parameters for a plurality of different vehicle speeds, wherein modeling the steering system includes performing an off-line process to determine an off-line steering model and an on-line process to correct the off-line steering model in real time during vehicle operation.