Abstract: In terms of the features of Cobots and characteristics of over-running clutch a kind of power-aided joint mechanism is put forward based on two unilateral over-running clutches. The mathematic models of over-running clutch and dynamics model of joint mechanism are built up by applying Lagrange method of work energy equilibrium. The simulation analysis is carried out for the dynamic characteristic of insufficient power joint mechanism. Trajectory control strategy based on operation force is put forward, and virtual trajectory control model of Cobot is built up by using differential geometry principle. The experimental study of trajectory control of insufficient power Cobot is completed based on dSPACE hardware in loop simulation platform. The research results illustrate that the Cobot prototype can track a desired path, the joint mechanism of which can get over friction resistance, and it makes operation convenient and labor saving. It can meet the design requirements of insufficient power Cobot.

Key words: Actuation control, dSPACE, Insufficient power, Virtual trajectory