1 Introduction
Mars entry, descent, and landing are fraught with systems engineering challenges [1, 2]. One of the challenges is a Mars entry accurate dynamics modeling which has larger uncertainties in physical and aerodynamic parameters of entry vehicles after a long-time flight. The dynamics model of Mars’ entry into the atmosphere is the prerequisite and foundation for subsequent work, and the accuracy of modeling will not only affect the correctness of the simulation results, but also the accuracy and safety of landing. The main difficulty of Mars entry accurate dynamics modeling comes from the fact that there is very little observable information about the upper atmosphere of Mars and the large uncertainties in the relevant aerodynamic parameters after a long flight. The proposed of fuzzy control theory provides an effective theoretical support for establishing an accurate dynamics model, but most of the current research focuses on fuzzy systems with linear time-invariant subsystems, which are relatively limited when considering the time-varying characteristics of the system. The limitations [3] emanate from (a) “rule explosion” issue and (b) “approximate” description of time-varying properties. As Mars environment has significant time-varying characteristics, it is necessary to introduce time-varying parameters as condition variables into fuzzy rules, which is bound to increase the number of fuzzy rules. Besides, the introduction of time-varying parameters will bring more conservatism because the T-S fuzzy model is an approximate description of the original nonlinear dynamics.