中文摘要：

拉索作动器己被引入结构振动控制中，但作动器具有单边饱和的非线性特点，因此，拉索控制难以直接采用要求控制无约束的LQG对结构振动进行控制律设计。针对拉索的单边饱和特点，提出了一种用分段性能指标代替原有的二次型性能指标的最优控制方法。将拉索的单边饱和特性考虑在内并以合适的抑制速度对结构振动进行控制。并证明了直接用LQG方法对结构振动进行控制律设计，通过拉索控制器取单边和饱和之后作用于结构也是一种最优控制。同时证明了加观测器的最优控制系统对结构振动控制是稳定的。对一悬臂梁振动进行数值仿真控制，结果验证了该最优控制率的可行性。

英文摘要：

Cable actuator has been used for structure vibration control. But unloaded cable actuator exhibits unilateral and saturated nonlinearity. As a result, LQG, which needs unconstraint control output, can not be adopted to design control law directly. According to the nonlinear characteristics of the cable, an optimal control law with a piecewise performance function is derived to substitute the quadratic performance function. Although the unilateral and saturated nonlinearity exists on the cable actuator, the proposed optimal method can obtain a suitably attenuating ratio for the structure vibration control. An important conclusion is obtained that the control signal designed by LQG and with cutting cable actuator nonlinearity is optimal. The stability of the optimal control system with Kalman Filter is also proved. The proposed optimal control law is simulated on a cantilever beam, and the result shows that the optimal method is effective.