Abstract:Development of new transmission need for a certain load of cycles loading fatigue test, to verify the reliability of the internal gears, shafts, bearings, housing and other components and the overall system, hydraulic loading transmission fatigue life test system is an important test equipment. In the fatigue life test, torque loads were commonly controlled by using the hydraulic loader to adjust pressure, but the temperature, the mechanical structure state and other factors could cause fluctuations in torque, so the hydraulic loader pressure was needed in real-time adjustment to ensure the test stability of torque. By studying the test torque proportion intergral differential (PID) control and automated process control method in the test system, one united was developed and implemented with functions of speed and torque adaptive control, test process automation, test data required storage automatic, and having high degree of automation control system. Fatigue life test results indicate that the measurement and control system allows the hydraulic loading type transmission fatigue life test-bench to have a higher level of automation and precision measurement and control, and has broad application prospects.