第三章能控性与能观性,Pontryagin极大值原理,Hamilton Jacobi方程最佳控制问题就是寻找某个反馈控制规律使闭环系统的某个性能指标达到极小,因此又称极值控制。在最佳控制理论中Pontryagin极大值原理占有特殊地位,事实上它给出了最佳控制应满足的必要条件,而Hamilton-Jacobi方程给出了充分条件,它们构成了最佳控制的理论基 Chapter III Controllability and observability, Pontryagin maximum principle, Hamilton Jacobi equation optimal control problem is to find a law of feedback control to a closed-loop system to achieve a performance index is extremely small, so called extreme value control. The Pontryagin maximum principle occupies a special place in the optimal control theory. In fact, it gives the necessary conditions for the optimal control to be satisfied. The Hamilton-Jacobi equations give sufficient conditions, which form the theoretical basis for optimal control