TIME-DELAY CONTROL OF STRUCTURES

Time-delay causes unsynchronized application of the control forces whi ch may not only degrade the performance of the control system but also even induce instability to the dynamic system. Time-delay control alg orithm is developed in this paper to solve this practical problem. The control system is first formulated in discrete-time form. In the pres ence of time-delay, the motion equation of the discrete-time control s ystem remains a difference equation which can be transformed into firs t-order difference equation by augmenting the state variables. Optimal time-delay control algorithm is derived based on the augmented system . The time-delay control forces are simply generated from the time-del ay states multiplied by the constant feedback gain, Numerical simulati on is illustrated to verify the feasibility of the proposed control al gorithm. Since time-delay effect is incorporated in the mathematical m odel for the structural control system throughout the derivation of th e proposed algorithm, system performance and dynamic stability are gua ranteed.