Structural synthesis of the reconfigurable legged mobile lander for strong geometry-physical interaction with extraterrestrial environment

Abstract

To design the engineering prototype of reconfigurable legged mobile lander (ReLML) for strong geometry-physical interaction with extraterrestrial environment, this paper proposes a tailored structural synthesis methodology unifying kinematic geometry and statics. Compared with our preceding works, three inbuilt operation modes are first integrated: adjusting mode is a totally new mode defined as three rotations (3R) with a strong geometrical adaptation to hostile terrain; landing mode is redefined as two rotations one translation (2R1T), inherits Chang'E lander to survive from strong impact interaction; roving mode turns into the other 2R1T motion for good motion/force interactivity. The interaction characteristics (motion, force, energy) between ReLML and environment are extracted to derive output finite motions and instantaneous wrenches of leg end-effector, following the principles of optimal force system equilibrium and work efficiency. The motion and force synergistic syntheses of metamorphic limb and joint are implemented to design and assemble mechanical generators. The ReLML can serve the alien base construction and adjustable launch bracket. The unified structural synthesis methodology of kinematic geometry and statics is universal and effective for designing parallel mechanisms and reconfigurable mechanisms, especially for strong physical interaction scenarios.