Abstract: Aiming at the entry, descent and landing (EDL) operations of Tianwen 1 lander, a high fidelity simulation model of the EDL sequence including the separation of the heatshield and the backshell is established, taking into account the dynamic characteristics of the parachute. For the flight process of the lander from hypersonic to subsonic, especially the interaction between parachute, lander, heatshield and backshell during the parachute descent phase, the dynamics are modeled which include 6 DOF dynamic model of the lander, the parachute/lander (backshell) system model, and the heatshield (backshell)/lander system model. Combining the mechanical environment model of the lander and the parachute as well as the guidance strategy for entry and landing sequence, a simulation model of the EDL sequence is constructed. A detailed analysis of the dynamic characteristics of the lander during Mars entry and landing is presented with the trajectory simulation of the EDL sequence of Tianwen 1 lander. Compared with the flight trajectory of Tianwen 1 lander, the trajectory is highly consistent, verifying the accuracy of the model.

Key words: Tianwen 1 lander, Entry, descent and Landing, Dynamic modeling