The Optimization Design For Multi-axle Electro-hydraulic Steering System

At present, in the multi-axle electro-hydraulic steering system, there are some problems that abnormal wear of tires and steering tie rod deformation led by mechanical and hydraulic mismatch as well as response speed and stability of the steering hydraulic system are low. In order to solve these problems and raise steering performance, this article will launch the research from following several aspects:(1) The optimal design of single-axle steering system was performed. The balance model for tires steering resistance, steering trapezoidal mechanism stress and steering cylinder force of single-axle steering system was build. The simulation verification of the virtual model built in ADMAS/View has been carried out. Based on the model, the minimality output power of the steering cylinder is the target. By using the fmincon function of the Matlab optimization toolbox, the optimization design was performed. The optimal installation location formulas of steering cylinder were obtained.(2) Through multidisciplinary system simulation software AMEsim, the hydraulic system simulation model was established. By AMEsim batch tool, the optimized parameters scope of the hydraulic system pressure, flow, pipe, and the PID were obtained. In this scope, the orthogonal simulation experiment of six factors and five levels was carried out. The optimization results of the pressure, flow, pipe parameters and the PID parameters of steering hydraulic system were got.(3) The system transfer function from the current signal of controler to the steering angle was deduced. The control algorithm of CMAC-PID and PID were simulated in Matlab softwar. The results of system tracking show that the control system of CMAC-PID has better response rate, precision and stability.(4) The test of multi-axle steering cylinder control system was constructed. On the TTC200 controller, the tracking experiment of PID control algorithm was performed. Based on the industrial control system of PCI-1712 data acquisition card, the tracking experiments of the CMAC-PID and PID control algorithm were conducted. The result shows that the CMAC-PID algorithm is superior to the conventional PID algorithm, the industrial control system is better than the TTC200 control system.