Full state constrained command filtered output feedback control for the electro‐hydraulic ammunition ramming system

Abstract

A barrier Lyapunov functions-based command filtered output feedback control scheme is presented for the electro-hydraulic ammunition ramming system (EHARS) with position and velocity constraints in this paper. Due to the limitation of compact installation space in ramming mechanism, there remain some immeasurable signals such as the velocity of projectile and pressures in hydro-cylinder; thus, a state observer is designed to estimate the unmeasured states of EHARS. The barrier Lyapunov functions theory is adopted to guarantee position and velocity constraints of projectile are not violated. In order to suppress the complexity of differential explosion in backstepping iteration, command filtered technology and corresponding compensating technique of filtering errors are applied. By the stability theory of Lyapunov, the stability of the closed-loop system and the boundedness of the whole state in EHARS are theoretically proved. Simulation results show prescribed position-tracking accuracy and desired velocity of projectile under different firing angles, which indicates the effectiveness of the proposed method.

Tracking control based on proportional resonant controller for electro‐hydraulic systems with input delay

“…Electro-hydraulic systems have been widely applied in various occasions, such as heavy vehicles [4], wave energy converters [5], large offshore wind turbine [6] and multi-DOF platform [7]. However, electro-hydraulic systems exhibit strong coupling with complex non-linear flow dynamics and parameter uncertainties [8,9]. To address the challenges posed by system non-linearities and parameter uncertainties, multi-ple control methods are proposed, including extended state observer [10], backstepping adaptive control [11] and model identification method [12].…”