Mechanical Design and Prototype of a Reconfigurable Actuated Universal Joint

This paper presents the mechanical design and prototyping of a reconfigurable universal joint. An electronically actuated mechanical switch allows to change joint’s configuration so that two different universal pairs can be obtained. One of the two revolute axes rotates freely whereas the other is driven by a servomotor: its direction can be chosen by the user, providing two different mechanical arrangements. It can be demonstrated that the use of this reconfigurable joint in a specific parallel kinematic manipulator equipped with three identical legs allows to change the mobility of its moving platform. The design proposed in the current work has been driven by analytical analyses and multibody simulations. A finite element analysis demonstrates the effectiveness of the mechanical design.