Closed-Loop Transmission Routings for Cartesian SCARA-Type Manipulators Available to Purchase

SCARA-type manipulators are widely used in industry. SCARA motions can be produced by serial SCARA arms or by Cartesian rail-mounted mechanisms, such as in overhead cranes. This paper focusses on the latter mechanisms which are referred to here as Cartesian SCARA-type manipulators. When such mechanisms are actuated, the motors are generally moving, which increases the inertia of the system. In this paper, several closed-loop cable/belt routings are proposed in order to allow the actuation of Cartesian SCARA-type manipulators from four actuators fixed to the ground. Then, the kinematic analysis of these routings is performed, which reveals that decoupled actuation is possible and leads to great advantages regarding the power needed. Finally, preferred routings are selected and an example of application is given.