The invention discloses a 15-degree-of-freedom whole
vehicle dynamics modeling method for a steer-by-wire
system, and the method comprises the steps: dividing a whole vehicle model into six dynamics modules: a vehicle body model, a nonlinear tire model, a suspension model, a wheel motion model, a
motor model, and a steer-by-wire model; in addition, a tire
slip angle and
slip rate state quantity calculation module and a steer-by-wire control module are adopted, a whole vehicle dynamic model is established and comprises
six degrees of freedom of longitudinal, lateral, yawing, pitching, tilting and vertical movement of a vehicle body,
two degrees of freedom of rotation and vertical movement of four distributed wheels and one degree of freedom of vehicle steering, and the total number of the
degrees of freedom is 15. The method designed by the invention is suitable for common
vehicle driving conditions so as to research the control performance, the stability, the safety, the dynamic response and the characteristics of a steer-by-wire
system of the vehicle and vehicle performance under different working conditions, and theoretical support is provided for optimization of future vehicle design and control strategies.