A Bioinspired Structure-based Adaptive Constraint-Following Control for Nonlinear Suspension Systems with Measurement Errors

This study presents a bioinspired structure (BIS) based adaptive constraint-following control (CFC) framework for active suspension systems to enhance ride comfort and safety under stochastic, transient, and periodic road excitations. First, an ideal BIS reference manifold is constructed in the form of servo constraints and used exclusively as a control reference, providing a unified mathematical description of the nonlinear dynamic characteristics generated by the bioinspired structure. Based on this formulation, a manifold-based constraint-following control strategy is developed to drive the suspension dynamics toward the BIS-defined reference manifold, ensuring bounded constraint-following errors, control inputs that remain within physical actuator limits, and robustness to state measurement errors. Second, stability and constraint-satisfaction properties under random, bump, and sinusoidal excitations are analytically verified and numerically validated. Finally, hardware-in-the-loop experiments confirm real-time feasibility, showing significant reductions in body acceleration and suspension deflection compared with passive and sliding-mode controllers while requiring comparable control effort. The results demonstrate that the adaptive CFC achieves smooth reference-manifold tracking, explicit handling of constraints in the control design, and resilient performance, offering a physically consistent solution for intelligent vehicle suspension control.