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Published on: November 24, 2021
Safety control for nonlinear systems with unknown relative degree
Yupeng Shi1, Lijun Long2, Lingbo Geng3
1College of Information Science and Engineering, Northeastern University, Shenyang, 110819, China.
Abstract:
This paper is concerned with the problem of safety control for nonlinear systems subject to multiple constraints with different unknown relative degrees. A novel control design approach is developed to guarantee the safety of nonlinear systems by using a control input filter and a high-order switching differentiator (HOSD). In particular, the time-derivatives of the safety function are estimated to facilitate the control design. Also, the control design approach offers significant advantages in terms of the absence of the assumption that the relative degree of the system is known in any part of the state space. Finally, we illustrate the effectiveness of the proposed approach through both a numerical example and a practical problem based on a 2-mass lumped-parameter structure.
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