Design and experiment of load simulation system for servo mechanism of rocket engine nozzle

A new electro-hydraulic torque load simulator is proposed for the semi-physical simulation of the servo mechanism in launch vehicle, which could simulate the inertia load, friction and elastic torques, and servo mechanism mounting rigidity. On the basis of load characteristics of servo mechanism, the inertia, friction, and servo mechanism mounting rigidity are simulated for the mechanical structures, and the elastic load is simulated for the servomotor. The complete mathematical models of the motor loading system and the servo mechanism system are constructed. A control system of the servo mechanism is designed based on speed compensation and torque feed-forward. Some field tests of load simulation device were made. The test results show that the various loads meet accuracy requirements. The proposed design is reasonable and practicable, and the control system is effective.