Predefined–Time Adaptive Control of a Piezoelectric–Driven Motion System With Time–Varying Output Constraint

This brief investigates the output feedback adaptive tracking control of a piezoelectric–driven motion (PDM) system with time–varying output constraint. The key features of the developed predefined–time adaptive neural control (PTANC) method are as follows. i) A broad learning system with recurrent enhancement node (RENBLS) is used to construct an RENBLS–based observer such that state information can be estimated; ii) we incorporate a performance regulator and time–varying barrier Lyapunov function (TVBLF) into the controller design. The proposed method can then achieve the control effect in a predefined time without violating the output constraint. Stability analysis of the PTANC strategy is demonstrated in theory. Furthermore, the effectiveness of the proposed control scheme is experimentally verified via the PDM system.