Guidance and Control Design for Hazard Avoidance and Safe Landing on Mars

摘要

To ensure successful future Mars landing missions, the lander must be capable of detecting hazards in the nominal landing zone and maneuvering to a new and safe site. Trajectory guidance and attitude commanding are formulated for the terminal descent phase when the lander is off the parachute. The autonomous six-degree-of-freedom controls are accomplished using engines and thrusters and guided by onboard hazard-avoidance sensors. The algorithms determine the available landing zone, survey them for hazards, select the best or alternate landing site based on state estimates and available propellant, and then maneuver the lander to land safely at the selected site. Computer simulations have demonstrated the satisfactory performance of the algorithms for safe landing on Mars with assumed atmospheric environments.