针对预测控制在高超声速飞行器控制中面临的在线计算时间问题,提出了离线双模预测控制方法。首先采用LQR方法设计无约束反馈控制增益,然后根据计算得到的控制增益和高超声速飞行器的约束条件计算多面体不变集,根据多参数二次规划解的性质将多面体不变集进行区域划分并计算相应区域的自由控制变量。在线时只需要搜索当前时刻状态所处的分区,极大地减小了在线计算时间,为高超声速飞行器的实时控制提供了保证。仿真试验表明,提出的方法在保持在线算法的控制性能的同时,极大减少了仿真运行时间,实现了高超声速飞行器的实时控制。
Considering the problem of the online computation time in the model predictive control for hypersonic vehicle,the off-line dual-mode predictive control was proposed. Firstly,the unconstrained control gain was designed by using the LQR( Liner quadratic regulor) method. Then the polyhedral invariant set was calculated according to the control gain and the constraints of the hypersonic vehicle. The polyhedral invariant set was divided based on the solution of the multi-parameter quadratic program,and the relevant free control variables were calculated simultaneously. On-line,the control law was obtained by searching the region of the current state,which reduces the online computation time noticeably. Simulation results show that the proposed method can not only maintain the control performance but also reduce the simulation time,and the real-time control for hypersonic vehicle can be attained.