Management of parallel-manipulator singularities using joint-coupling

Joint-coupling (JC) is introduced in the design and control of parallel manipulators for managing manipulator singularities. The underlying idea consists of coupling the motions of several manipulator joints by driving the joints with a single actuator. This can be done by mechanical or electronic means, while preserving the mobility of the manipulator. Such JC is intended to alter the direct singularity condition of parallel manipulators upon changing the coupling coefficients. Both 2and 3-d.o.f. planar parallel manipulator examples are provided to illustrate the concept of JC and singularity management. The prototype of a JC device and its associated 2-d.o.f. parallel manipulator intended for a feasibility study is introduced.