A predefined-time stability control method based on fuzzy compensation for Euler–Lagrange systems and its applications to manipulators

This paper presents an approach to predefined-time terminal sliding mode control (PT-TSMC) for Euler–Lagrange systems (ELSs) with actuator control input saturation, leveraging fuzzy compensation techniques. Initially, the paper focuses on tunable predefined-time stability (PTS), providing adjustable parameters to fine-tune the system's stability time, thereby enhancing the adaptability of the controller design. Based on this approach, a control input system is formulated to ensure predefined-time stability for Euler–Lagrange systems. Additionally, a strategy is proposed to enhance system performance, including robustness improvement, chattering reduction, and singularity elimination, through the design of an adaptive fuzzy logic system (AFLS). The AFLS estimates unstructured model uncertainties and compounded disturbances, seamlessly integrating them into the control system. Notably, this approach effectively addresses the challenge of handling unknown model data. Finally, comprehensive comparative simulations demonstrate the effectiveness of the proposed method, showcasing its commendable control performance.