Parametric study of Lunar Landers

Details

Supervisors

Fisette, Paul

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil mécanicien

Abstract

This thesis aims at presenting a first model to quantitatively assess how two configurations of propulsion (thruster cluster and gimbaled thruster) influence the maneuverability of planetary landers, understand limitations and assess the boundary conditions to provide the optimal design solution(s). As a key exploration destination, the Moon was chosen as a practical test case in conjunction with the geometry and mass properties from the Apollo Lunar Module program. This is only a specific example to study but with the model presented can be easily changed to adapt it to other landers or planetary bodies. To find useful decision-making information, the dynamics of both configurations performing a soft landing were modelled and tested via numerical simulations. with the multibody software ROBOTRAN [1] and a control implementation in MATLAB. Thanks to the symbolic generation of the equations of motion, ROBOTRAN simulates the model and analyses the problem at hand . Indeed, its modularity gives the user the freedom to model complex articulated systems very easily, while retaining a deep understanding of the problem. The parameters under study are the mass of the payload and the maximum thrust of the thrusters. The optimization objectives refer to the maximum acceleration (truly important for manned missions), the amount of fuel used to control the spacecraft and the mechanical stresses on the structure and on the actuators.\\ The numerical results will show the optimal configuration (i.e. thruster cluster or gimbaled) for specified parameter ranges (e.g. for the payload mass). The thesis also discusses how the criteria for a good design may change depending on the application. Thanks to this project, designers will make the most of a faster approach, to quantify how each system dynamically performs and to evaluate its limitations. The project originates from an initiative of SABCA’s actuation system business unit in collaboration with the Mechatronics Division (MEED) of the Université catholique de Louvain.