In this paper, we consider a suboptimal control problem for nonlinear systems with unmatched disturbance via integral sliding mode control and policy iteration. Firstly, the unmatched disturbance is estimated by a nonlinear disturbance observer. Secondly, the integral sliding mode controller based on the disturbance estimation is designed to guarantee the reachability of the sliding-mode surface. Furthermore, the policy iteration approach based on actor-critic neural networks is used to design the suboptimal controller, which can achieve the desired performance. Finally, the effectiveness of the proposed approach is demonstrated through simulation examples.

中文翻译：

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通过积分滑模控制和策略迭代对有扰动的非线性系统进行次优控制

在本文中，我们通过积分滑模控制和策略迭代来考虑具有不匹配扰动的非线性系统的次优控制问题。首先，不匹配的扰动由非线性扰动观测器估计。其次，设计了基于扰动估计的积分滑模控制器，以保证滑模面的可达性。此外，基于actor-critic 神经网络的策略迭代方法用于设计次优控制器，可以实现所需的性能。最后，通过仿真实例证明了所提出方法的有效性。