Tianwen-1 Mars entry vehicle trajectory and atmosphere reconstruction preliminary analysis

Abstract

The Tianwen-1 Mars entry vehicle successfully landed on the surface of Mars in southern Utopia Planitia on May 15, 2021, at 7:18 (UTC+8). To acquire valuable Martian flight data, a scientific instrumentation package consisting of a flush air data system and a multilayer temperature-sensing system was installed aboard the entry vehicle. A combined approach was applied in the entry, descent, and landing trajectory reconstruction using all available data obtained by the inertial measurement unit and the flush air data system. An aerodynamic database covering the entire flight regime was generated using computational fluid dynamics methods to assist in the reconstruction process. A preliminary analysis of the trajectory reconstruction result, along with the atmosphere reconstruction and aerodynamic performance, was conducted. The results show that the trajectory agrees closely with the nominal trajectory and the wind-relative attitude. Suspected wind occurred at the end of the trajectory.

Nonlinear Covariance Analysis-Based Robust Rendezvous Trajectory Design by Improved Differential Evolution Method

“…[24] by the quantification of both the dynamics of parametric uncertainty and initial state uncertainty. The Mars entry trajectory of Tianwen-1 was designed based on the estimation of uncertain aerodynamic states [25]. The uncertainties of the RPO process have been analyzed and quantized in the open-loop system, and the effect of the uncertainties was evaluated.…”