A robust fault-tolerant control for active suspensions subject to Markov type actuator faults

A Robust Control for a Controllable Suspension System with an Input Time Delay

“…In order to make the system insensitive to such perturbation uncertainties and faults, a robust fault-tolerant control is needed. Considering this, extensive research has been carried out on topics such as state feedback passive robust fault-tolerant control [6,7], adaptive robust fault-tolerant control [8], sky-hook fault-tolerant control [9], linear variable parameter control (LPV) [10,11], linear variable parameter model predictive control (LPV-MPC) [12], adaptive fault-tolerant control via the T-S fuzzy method [13], H2/H∞ passive robust fault-tolerant control [14], hybrid control of state feedback compensation and nominal state feedback [15], constrained adaptive backstep tracking controllers [16], H∞ passive robust fault-tolerant control based on output feedback [17], adaptive state feedback robust fault-tolerant control [18], and fault-tolerant prescribed performance control [19]. The above-mentioned research has achieved excellent results.…”

“…A time delay can cause the actuator output control force to be out of sync with the control force required by the system, possibly resulting in system instability or performance deterioration [21]. However, the above studies on robust fault-tolerant control of suspension systems do not consider the influence of input time delay [6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Moreover, there is a wealth of existing research on the time delay control of suspension systems, including adaptive backward-step time delay control [21], H∞ state feedback time delay control [22,23], H∞ output feedback time delay control [24], and fuzzy static output feedback (SOF) time delay control based on parallel distributed compensation (PDC) [25].…”

“…In summary, the industry has conducted in-depth studies on fault-tolerant control in V-CSSs [6][7][8][9][10][11][12][13][14][15][16][17][18][19] considering system faults. Time delay control [21][22][23][24][25] explores the effect of a system time delay.…”

“…In addition, among the above studies on fault-tolerant control, both passive faulttolerant control [6,7,14,17], following the idea of "responding to all changes with no changes" and active fault-tolerant control [8,13,16,18], based on the principle of "changing to change", are included, both of which have their advantages and disadvantages. Although the design of passive fault-tolerant control is conservative, when the delay factor is introduced into fault-tolerant control, the improvement it brings to the system's overall dynamic performance and stability can compensate for the performance loss caused by conservatism.…”

“…(2) Unlike previous studies on control methods for V-CSSs with partial consideration of the uncertainty, faults, and input time delay [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25], this study deals with all of the above essential factors, focusing mostly on an adjustable damping suspension system. By introducing the idea of robust control, a time-delay-dependent H∞ state feedback robust control law based on Lyapunov stability theory is designed and transformed into a convex optimization problem of linear matrix inequalities.…”