Study And Improvement Of Control Technology Of Brake Hose Burst Property Test Bench

This subject improves control system of test bench that is used to test burst property brake hose of automobile.Before the test bench hasn't been improved, operator add pressure to brake hose by handing regulate pressure-biased valve according to the display of instrument. The accuracy of test is very low. Because the pressure difference of pressure-biased valve is very high in the test and the unsteadiness of hand operation, the pressing speed of brake hose is unequable, and the pressure will tend to appear steep ascent, which make test failure. This subject improve pressure-biased valve to digital valve which is associated by throttle and step motor. The digital valve is controlled by PLC. The pressure speed is controlled by auto-regulate valve opening size. In order to solve the problem that torque of step motor is too small and the stepping angle of step motor is too big, gearbox is used to associate step motor and valve. The stepping angle is further subdivided by use the function of step motor driver's subdivision, which make the angle of every pulse very small in theory, which improve the accuracy of control system.Fuzzy control strategy is used to simulate man operate process. Control rules are determined by operational experience. Firstly, the query table of test bench fuzzy control quantity is calculated by off-line. Then, fuzzy control strategy is realized in PLC program by use lookup table of indirect address.Control function of test bench is realized by slave computer-PLC. The host computer is PC, which save and view test result and data. The monitoring and control interface in host computer is established by WinCC. The interface written by VB is used to manage compressed archived data in database.Finally, according to the test result, the improvement of test bench control system is successful basically.