Abstract:  To solve the movement interference happening during the motions of modular robots, an optimized structure design is proposed and applied to the MLattice modular robots. By introducing a translational joint, the mechanical arms of modular robots are able to shrink and stretch to avoid the movement interference. Through the kinematic analysis,  the movement interference can be avoided and also the stroke of translational joint can be minimized, then the modular robots can successfully realize the selfreconfiguration process and ensure the structural strength as well as the stability of the robots. The feasibility and motor ability of optimized structure are verified through the simulations of motion spaces under different situations and the experiment of prototype robots. The results show that the introduced translational joint can well avoid the movement interference happening among the adjacent modules, that the design of each mechanical joint is operable, and that it establishes the foundation for the further researches about large scale modular robotics system.

Key words:  lattice type, modular robot, movement interference, kinematic analysis, structure optimization