Adaptive Robust Control for Nonlinear Mechanical Systems With Inequality Constraints and Uncertainties
针对机械系统中不可避免的不等式约束、非线性、参数不确定性和外部干扰，提出一种自适应鲁棒控制算法，通过微分同胚变换将有界状态变量转换为无界变量，并利用泄漏型算法保证系统实际稳定，以永磁直线电机系统验证了方法的有效性。
The inequality constraints, system nonlinearities, parameter uncertainties, and external disturbances are always unavoidable in practical mechanical systems. This article proposes an adaptive robust control (ARC) algorithm from the view of servo constraint following to tackle the control problem of mechanical systems subject to the above factors. For the inequality constraints, a creative diffeomorphism which could convert the two-sided bounded state variables to the unbounded ones is explored, which could render the transformed nonlinear system free from inequality constraints. For the system uncertainties, a leakage-type ARC algorithm is developed, which could render the system the practical stability. The permanent magnet linear motor (PMLM) system is utilized as a typical application to verify the proposed state transformation and ARC approach. Numerical simulations show that the displacement of the PMLM system could well track the desired trajectory without violating the given bound line.