Abstract:In order to reproduce the complex loads that the object bears in the actual project, based on the phase control an electrohydraulic fatigue test system with two vibrators is presented. Mathematical models of exciter and fatigue test system were established with the theory of fluid dynamics and system dynamics. A nonlinear analysis of the excitation-response characteristics of the exciter was made, and the loading strategy of the fatigue test system was worked out. Finally, a test platform was built to verify the accuracy of the theoretical analysis and the feasibility of the loading strategy. The results show that the wave form of measured output force of the exciter is basically the same with the simulation results, and the proposed three loading modes can achieve the desired goal. That is, the fatigue test system can output tension-compression alternating force, alternating torque and alternating force moment with different frequencies and extremes to meet the needs of the test.