Memory-Driven Dynamic Output Feedback Control for Networked Active Suspension System With Time-Varying Input Delay

This study addresses the output feedback control synthesis problem for a quarter-vehicle active suspension system subject to input delay, using dynamic integral quadratic constraint. To account for the uncertain relationship between the real-time output of the controller and the delayed signal arriving at the actuator, a memory-driven control strategy is proposed. Furthermore, dynamic integral quadratic constraint multipliers are employed to reformulate the output feedback control synthesis problems into a set of linear matrix inequalities. A simplified memory-free dynamic output feedback controller is also introduced. Corresponding controller design algorithms are developed for both the memory-driven and memory-free schemes. Simulation results demonstrate the effectiveness of the proposed controllers in handling input delays, and comparative studies verify the superiority and feasibility of the proposed control approach. Note to Practitioners—Time-varying input delays in vehicle active suspension systems caused by communication delays or actuator limitations can degrade control performance and even destabilize the system. However, conventional controllers struggle to balance delay compensation with design complexity. To address this matter, this study proposes a memory-driven dynamic feedback control method that addresses delay-induced uncertainties between controller outputs and delayed actuator inputs. Specifically, the controller design is streamlined into a computationally efficient solving algorithm, achieving enhanced engineering practicality by avoiding intricate theoretical frameworks. Simulations demonstrate enhanced driving comfort and stability under severe delays, making it suitable for self-driving vehicles, industrial machinery, and other delay-sensitive applications. Ultimately, experimental results under severe delay conditions demonstrate marked improvements in ride comfort (reduced vibration transmission) and stability (enhanced road-holding capability), making it suitable for self-driving vehicles, industrial machinery, and other delay-sensitive applications.