Solution for asymptotic tracking control of nonlinear MIMO systems with input derivatives and actuation saturation

This paper presents a novel tracking controller for nonlinear multi-input multi-output systems, addressing actuation and system input constraints, and control input derivatives. It employs sliding mode control with power reaching law and variable sliding surfaces, mitigating null solutions in conventional designs. Moreover, incorporating control rate limitation as a complex hard constraint, actuator dynamics are embedded into the open-loop structure using Adams-Moulton time-discretization technique. Quadratic programming is applied to optimize control inputs, unifying velocity and position commands for enhanced tracking precision, while guaranteeing asymptotic stability and ensuring robustness. The proposed controller's efficacy was compared with several baseline methods. Real-time implementation on an Intel® i7-7700HQ via Linux real-time kernel (Xenomai 4, 7.594-milliseconds execution, 0 % miss rate) validates its practicality for high-impact MIMO system applications.