Design and kinematic analysis of a 6DOFs omnidirectional mobile robot for the gesture expression

A new 6DOFs omnidirectional mobile robot with three leg-wheel hybrid structures is suggested to perform the human body gestures. The omnidirectional property of the human body is determined by investigating the motion capture data of the human body gestures. The offset between the steering and the wheel axis is inserted to remove the singularity of the leg-wheel hybrid structures and the spherical shape wheel is introduced to simplify the contact problem. The kinematic constraints caused by the contact and no slip conditions are derived in position, velocity and acceleration level and the equations for the desired joint trajectories according to the given body gestures are obtained in two versions, hip-knee coupled and decoupled structure. The results are shown with the human body gestures in the kinematic simulation.