Simplified dynamic modelling and improvement of a four-degree-of-freedom pick-and-place manipulator with articulated moving platform

This paper deals with high-speed robots for pick-and-place applications with a high rate of output. After mentioning the families of robot architectures that meet the specifications of pick-and-place, parallel kinematics architectures with articulated moving platform are introduced and described. Indeed, this concept seems very promising for this kind of application. After presenting the reasons to select the PAR4 architecture, it is fully described and modelled: position relationships, velocity relationships, and simplified dynamic model. Experimental results from extensive testing show a high performance potentiality. By analysing the experimental results, an improvement is proposed to have a better dynamic balance among the actuators. The improved version of the robot is the one chosen for the industrial development of the QUATTRO parallel robot.