Exponential fast terminal sliding mode based finite-time control of manipulator systems

Abstract

A finite-time controller is designed based on an exponential fast terminal
sliding mode for multi-joint manipulators, which solves the problem of slow convergence
in trajectory tracking. By adding an exponential function on the basis of fast terminal
sliding mode, the convergence speed is greatly improved. In addition, a new fast
variable power reaching law is designed to reduce the chattering problem. The
approaching speed is adjusted by changing the size of the power term adaptively
in different stages of the approximation, so that the states of the system enter the
sliding mode surface faster and more stablely. The controller realizes the finite-time
trajectory tracking of the manipulator, shorens the convergence time and weakens
the chattering frequency. Finally, the above views are verified by simulation and
comparison experiments.