Adaptive Fast Fixed-time Sliding Mode Control For Uncertain Robotic Manipulators

In this paper, a novel adaptive terminal sliding mode (TSM) control method is suggested for the operation and adjustment of uncertain robots under the influence of internal parameter errors and external perturbations. Firstly, a novel TSM surface was designed with the aim of achieving continuous and smooth output torque while ensuring rapid convergence of tracking error. Secondly, the TSM is combined with adaptive control, and an adaptive mechanism is utilized to determine these unknown upper bounds, in order to implement accurate trajectory control in the existence of unknown lumped disturbance. The Lyapunov stability theory is utilized to prove global fixed-time stability, ensuring that the state of the system converges to the origin in fixed time. Importantly, the proposed scheme offers the advantage of continuous and transient-free control torque, eliminating undesired vibrations and ensuring smoother control torques that are well-suited for practical applications. Finally, the simulation experiments unequivocally establish the efficacy and superiority of the controller that was devised.