Spherical robot, rolling by altering its barycenter with the inside actuating device, has a spherical or spheroid housing, the motivity of which is supplied by the friction force between the housing and the ground while it rolling. Particular attention is paid to the research of spherical robot in recent years.
This paper presents a new omnidirectional bi-driver spherical robot droved by two motors that directly drive the balancer to rotate about two orthogonal axes. The spherical robot is a nonholonomic system with 3 DOF while it rolls on the ground, so the spherical presented in this paper is a nonholonomic under-actuated system, featuring omnidirectional movement, simple configuration, and so on.
Based on the structure of virtual assembly system, a comprehensive survey and analysis of the recent research in the field are given, which include assembly modeling, constraint recognizing and solving, collision detection, assembly plans and evaluation and so on. The future research trends are presented.