Fully hydraulic synchronous steering control of vehicle based on gain fuzzy sliding mode variable structure

Aiming at the problem that the expected steering curve determined by the existing methods has poor traceability and cannot achieve synchronous steering, a method for determining the expected steering curve and its feasible area is proposed. Aiming at the uncertainty of system disturbance and the nonlinearity of oil leakage, based on the combined reaching law, sliding mode control is adopted, and the saturation function is introduced instead of the sign function, which imposes certain constraints on the control system. Aiming at the problem that the combined approximation law lacks gain adaptation, a fuzzy rule table based on wheel angle and angular velocity is formulated, and the gain fuzzy sliding mode control is realised. Simulation and experimental results show that the expected steering curve based on steering efficiency has good tracking performance; the gain fuzzy sliding mode variable structure control has excellent dynamic response characteristics and control precision. It can effectively eliminate steering deviation and realise full hydraulic synchronous steering of steering system.