An improved footprint generation method for entry vehicles

作者:Wang, Tao; Zhang, Hongbo*; Li, Yongyuan; Tang, Guojian
来源:Proceedings of the Institution of Mechanical Engineers - Part G: Journal of Aerospace Engineering , 2017, 231(10): 1951-1956.
DOI:10.1177/0954410016662060

摘要

Entry landing footprint is an important index of the flight capability of an entry vehicle. Footprint generation methods can be classified into three categories, namely, methods based on the interpolation of the drag profile, methods based on the maximum cross-range, and methods based on virtual targets. This paper proposes a procedure for improving the methods based on virtual targets method by avoiding the problem of setting virtual targets. Taking the cross-range of the vehicle as the performance index, the optimal control law is used to develop the bank angle control law. Through coordinate transformation, the optimal control problem is transformed into a univariate root-finding problem that is similar to the result of the methods based on virtual targets method. But the method in the paper is more convenient for engineering application. At last, the footprint of the EG13 mission of X-33 is generated.