Relative threshold event-triggered prescribed performance control for vehicle active suspension systems with uncertainty

This paper proposes a novel control strategy to solve the tracking problem for uncertain vehicle active suspension systems (VASS). Under the proposed control framework, the overall VASS is divided into two subsystems owing to its particular structure: (1) for the first subsystem, to ensure the important state variable within the given restrictive conditions all the time, a novel prescribed performance control(PPC)-based intermediate controller is first designed; furthermore, a new relative threshold event-triggered controller is proposed based on the event-triggered control theory; Moreover, because the internal and external disturbances are inevitable in actual applications, system uncertainties are also considered. (2) for the second subsystem, which is regarded as zero dynamics of overall VASS, the corresponding zero dynamic stability analysis is presented; finally, the resulting closed-loop system is ensured to be stable in the sense of uniform ultimate boundedness. The effectiveness of the proposed approach is illustrated by simulation results.