Study On Position-control And Speed-control System Of Sliding Table In Automobile Low-speed Tire Testing Machine

In recent years, our country has got a great progress in the design and research of tire testing machine. The home already developed low-speed tire testing machine. Along with people's high requirement to the tire performance, the examination precision and experimental efficiency of existing low-speed tire testing machine could not meet the requirements by far. So we need to carry on the transformation to the existing low-speed tire testing machine, and comprehensively enhance the test precision and experimental efficiency.The tire's rotation is driven by the longitudinal reciprocal motion of low-speed tire experiment force sliding table, thus the tire's real motion condition is simulated. During the tire's rotation, verticality, side lean and side slant load is carried on the tire, then the tire's quality are judged by tire mechanics characteristic .So the sliding table's position and speed must be controlled accurately.Transmission function of valve-controlled symmetrical cylinder is derived out, according to the actual conditions of system, hydraulic pressure and the electric appliance part is chosen and the correlation parameters are calculated. Linear and nonlinear mathematical models of position-control and speed-control system of the sliding table are set up. Meanwhile system's state equations are listed by modern control theory, and nonlinear mathematical models of position-control and speed-control system of the sliding table are set up.Linear and nonlinear mathematical models of position-control and speed-control system of the sliding table are converted to the simulated models in MATLAB. The technical specification of the sliding table's position and speed under the step signal input are obtained by the separately simulation. Then many kinds of adjustments are carried on to the position and the speed control system, and the damping characteristic to the system stability and the control precision influence are studied. Finally the linear and nonlinear models are compared.Synthesizing above findings, the further study are carried on to the sliding table position and speed compound control system, and the difference of the conversion of position-control and speed-control system are analyzed in the different position .The corresponding control strategy are Studied to realize the sliding table's position and the speed compound control. Finally these adjustment methods and control strategies are given to how to realize in the actual project.