Implementing an Open-Architecture Controller for a Tension-Compression Fatigue Test Machine

In this research, an enhanced force control unit is proposed and implemented on a hydraulic tension-compression fatigue test machine. In this regard, different sensory data, such as force, hydraulic pressure, displacement and oil temperature is acquired and conditioned for controlling different subsystems of the machine. First, the transfer function of the system is identified. Then, a control strategy for applying cyclic force on the specimen with prescribed amplitude and frequency is proposed. The performance of the whole system is examined for the working range of the excitation frequency. In addition, the developed open-architecture controller can be used for testing the real parts found in various branches of industry. It can also be upgraded to be used on a universal fatigue test machine. It is shown that the designed controller can improve the performance of the machine significantly.