Force-unconstrained poses for a redundantly-actuated planar parallel manipulator

Redundant Actuation of Parallel Manipulators

“…A brief overview of redundancy in PKM can be found in (Merlet, 1996). Redundantly actuated PKM were analyzed with regard to their kinematic and dynamic properties, and in view of singularities in (Alba et al, 2007;Dasgupta & Mruthyunjaya, 1998;Firmani & Podhorodeski, 2004;Gardner et al, 1989;Kim et al, 2001;Kock & Schumacher, 1998;Kurtz & Hayward, 1992;Liao et al, 2004;Mohamed & Gosselin, 1999;Müller, 2005;O'Brien & Wen, 1999;Zhang et al, 2007). It was shown by a number of authors that redundant actuation is a means to eliminate singularities and so enlarges the usable workspace.…”

Wrench Capabilities of Planar Parallel Manipulators and their Effects Under Redundancy

“…However, there is an increase of mass and/or inertia due to the addition of actuators. Firmani & Podhorodeski (2004) eliminated families of singular configurations by adding a redundant actuator to the 3-RRR PPM, yielding a RRR-2RRR layout. Branch Redundancy.…”

Methods for Force Analysis of Overconstrained Parallel Mechanisms: A Review

“…It is well known that redundantly actuated PMs [19][20][21] have been investigated and utilized extensively, since redundant actuations can avoid kinematic singularities [22][23][24][25][26][27], enlarge load capability [28][29][30], improve dynamic characteristics [31,32], and eliminate backlash [33,34] of the mechanisms. The distribution of driving forces/torques of a redundantly actuated PM belongs to the statically indeterminate problem.…”