Performance Analysis Of Mars Powered Descent Based

Abstract

It is imperative to find new places other than Earth for the survival of human beings, which can be in our solar system or outside the solar system. Mars could be the alternative to Earth in future for us to live. In this context many missions have been performed by different space agencies to examine the planet Mars. For such missions, planetary precision landing is a major challenge for the precise landing of unmanned and manned missions on Mars. Mars landing consist of different phases (Hypersonic Entry, Parachute Descent, Terminal Descent comprising of Gravity turn and Powered descent), however in this work the focus is the powered descent phase of landing. Firstly, the main objective of this work is to minimize the landing error during powered descend landing phase. The second objective involves the constrained optimization in a predictive control framework for landing at non-cooperative sites. Different control algorithms like PID, LQR have been developed for the stated problem, however predictive control algorithm with constraint handling ability hasn’t been explored much. This research discusses the Model Predictive Control algorithm for the powered descent phase of landing. Model Predictive Control (MPC) considers input/output constraints in the calculation of the control law and thus it came out to be very useful for the stated problem as shown in the results. The main novelty of this work is the implementation of different variants of predictive algorithm. Along with MPC, Multiple MPC, Explicit MPC and Multiple Explicit MPC are the variants that have been explored and implemented for powered descent phase. The comparison is done among the variants of MPC in terms of feasibility, hard constraints and computational time. Moreover, other conventional control algorithms like PID and LQR are used as a comparative study with the proposed predictive algorithms. These control algorithms are implemented on quadrotor UAV (which emulates the dynamics of a planetary lander) to verify the feasibility through simulations in MATLAB. It was concluded that MPC and its variant can handle input/output constraints without causing feasibility issue