Research On Virtual Prototype Based Steer-by-wire

Steer-by-wire is an important system of drive-by-wire. Designing of steer-by-wire not onlyneed theoretical support, but also need method and test bench support.The paper reviews the domestic and foreign development of steer-by-wire; builds the bondgraph model of steer-by-wire by the bond graph theory. Steer-by-wire is the dual-inputdual-output system. If the steer angle through the steering wheel by driver and the current ofsteering motor as the system dual-input, the wheel angle and the force of feedback motor isthe dual-output.It builds up the variable ratio of the steer-by-wire system through the fuzzy theory andMATLAB fuzzy logic control toolbox, designs the torque for steering wheel as the "roadfeel".Through the co-simulation between ADAMS/car and MATLAB/Simulink, it builds up theSoftware-in-loop-simulation. And the fuzzy variable ratio of steer-by-wire is verified underthe angle input mode. The result show that: the fuzzy variable ratio can reduce the forceinput by driver in low speed, and the spirit in high speed. Also in the environment ofco-simulation, trough the force input mode, the road feel which reference by the input shafttorque, the torque of rack, the torque generated by the steering implement motor has nosignificant difference.Finally, the steer-by-wire system hardware-in-loop-simulation test-bench structure andalgorithm structure is discussed.