Polynomial‐Based Adaptive Nonsingular Fixed‐Time Tracking Control for Single‐Link Manipulator With Actuator Faults

ABSTRACT

This work investigates adaptive practical fixed‐time tracking control for a single‐link manipulator system with motor dynamics under unknown actuator faults, aiming to achieve precise tracking of the desired arm link angular position. A novel polynomial‐based smooth switching function method is proposed to address the singularity issues that arise in traditional fixed‐time control during the differentiation of virtual control laws. The proposed method ensures that the generated control laws are ‐continuous, effectively eliminating singularity issues. Additionally, an adaptive compensation mechanism is introduced to handle the challenge posed by unknown actuator fault coefficients without requiring any prior knowledge of fault parameters. By integrating backstepping design with Lyapunov stability theory, a practical fixed‐time fault‐tolerant control scheme is developed that guarantees that all closed‐loop signals converge to a small residual set within a fixed time independent of initial conditions. Finally, simulation experiments demonstrate the effectiveness of the developed control scheme under various actuator fault conditions, highlighting its strong tracking performance and fault tolerance capability.