Tianwen-1 Entry, Descent, and Landing Guidance, Navigation, and Control System Design and Validation

On 15 May 2021, the Tianwen-1 mission delivered a lander and the Zhurong rover to the Mars surface, which made China the second nation to successfully land and place a rover on that planet. The guidance, navigation, and control (GNC) system for the entry, descent, and landing (EDL) of the Tianwen-1 mission play keys role in guaranteeing a successful landing. In this paper, the Tianwen-1 EDL GNC system design is presented, including the GNC architecture, scheme, and algorithm; additionally, the system is validated through experimental tests, numerical simulations, and actual flight results from telemetry data.