Design and Simulation Of a steering engines’ stiffness testing system

Through the way of imposing sinusoidal torques of certain frequencies and amplitudes on the steering engines in servo state, and at the same time, measuring the changes of steering engines’ shaft angle, the system measures the steering engines’ stiffness. In the design of its structure, a frameless direct drive torque motor is used to provide loading torque, while with the aim of improving the torque loading performance and simplifying the control model, a spring beam is used to transfer torque. A control mode of three close-loop including torque, position and current is applied and a kind of explicit torque control based on position inner loop is achieved. The simulation results show that the desired goal can be achieved, which means that the amplitude and phase errors of the loading torque can both meet the requirement.