Vibration suppressive control of flexible-joint space manipulators based on Legendre pseudospectral method

The vibration suppressive control problem is a challenge of flexible-joint space manipulators, which is settled by solving the energy optimal nonlinear control problem in this paper. Based on Legendre pseudo-spectrum method, the nonlinear model of optimal control problem is converted into the corresponding nonlinear programming problem. The complex and difficult two-point boundary value problem is solved by SNOPT. Compared with the traditional controller, the simulation results show that the joint trajectory can obey the joint flexible factors to move from the initial state to the end smoothly with a better result of vibration suppression in the process of movement by using the LPM. It can also ensure the terminal control precision.