Hierarchical adaptive control for 3 DOF manipulator using sliding mode technique

In this paper, two nonlinear controllers for a hyper redundant articulated nimble adaptable trunk (ANAT) robot are presented. These controllers are based on sliding mode technique. The control strategy consists of controlling the last joint by assuming that the remaining joints follow their desired values. Then we apply backward the same strategy to the (n-1)-th joint, and so on until the first joint. First, we assume that the model parameters are perfectly known. A nonlinear controller based on sliding mode technique is then developed. Second, an adaptive version of the nonlinear controller is proposed. The asymptotical stability is proved using the well-known Lyapunov theory. Simulations are presented that show effective results and good tracking.