Model-Free Sliding Mode Control Based on Time-Delay Estimation and Ultra-Local Model for Manipulator Including Motor Dynamics and Input Saturation

In this article, a model-free sliding-mode controller(MFSM C) is proposed for the n-link manipulator including DC motor dynamics and saturation of input voltage. This developed MFSMC has high-precision position tracking with small chattering effect. The considered manipulator is a highly complex coupled system and contain many non-linearities, so it is challenging to obtain the system precise model information. The considered MFSMC combines the TDE-iPD sub-controller and a continuous nonsingular terminal sliding-mode sub-controller (CNTSMC) with integral-type sliding surface. Based on the ultra-local model, the time delay estimation is used to estimate unknown parts of the system. And the CNTSMC is used to guarantee convergence. Finally, to validate the superiority of the controller, a PUMA560 manipulator with motor dynamics and input saturation of voltage is used to carried out corresponding simulation. With Comparisons to time-delay estimation-based intelligent proportional-derivative control (TDE-iPD) and receding-horizon Model-Free control, the proposed MFSMC has the better control performance.