A New Methodology for Type Synthesis of Planar Linkages for Exoskeletons up to Five Angular Outputs

Mechanical linkage systems are a very important issue for exoskeleton design to meet the required number of angular outputs. In this paper, a new methodology is developed for type synthesis of planar linkages to establish a complete set of one degree of freedom (DOF) planar linkages with up to five angular outputs. Modified graphical representation is introduced for a four-bar mechanism as the initial angular output linkage. Then, a computerized procedure is presented to generate multiple angular outputs graphically by adding RRR dyads with parallel and series connections using Visual C++. A complete database of planar linkages with up to five angular outputs is successfully constructed. That helps designers to select the proper linkage for a given number of angular outputs. Some case studies have been discussed to validate the importance and efficiency of the proposed methodology that can be extended to generate linkage systems with any number of angular outputs for general robotic applications