Multi-Parameter Optimization of Angle Transmission Ratio of Steer-by-Wire Vehicle

Aiming at the problem of the insufficient stability of the unified model of steering angle transmission ratio at high speeds, we introduce a novel control strategy that integrates the yaw rate gain, lateral acceleration gain, vehicle speed and steering wheel angle, achieving great improvements in a simulation. The new control strategy uses a genetic algorithm to optimize the yaw rate and lateral acceleration gain values at different speeds, and the two are weighted. The ideal variable-angle transmission ratio control strategy is designed by using the unified model of steering angle transmission ratio at different speed intervals. The simulation results show that the strategy reduces the steering wheel angle peak by 67.12% compared with the fixed-angle transmission at low speeds. Compared with the unified model of steering angle transmission ratio at high speeds, the peak values of the yaw rate, the lateral acceleration and sideslip angle of the vehicle are reduced by 7%, 5.67% and 11.67%, respectively, which effectively improves the steering stability of the vehicle.