Cs. Tzafestas et al., A differential motion planning algorithm for controlling multi-robot systems handling a common object, CONTROL CYB, 29(2), 2000, pp. 567-584
Multi-robot systems have substantially increased capabilities over single-r
obot systems and can handle very large or peculiar objects. This paper pres
ents a differential (incremental) motion planning algorithm for an m-robot
system (m greater than or equal to 2) to cooperatively transfer an object f
rom an initial to a desired final position / orientation by rigidly holding
it at given respective points Q(1), Q(2), ..., Qm. One of the robots plays
the role of a "master" while other robots operate in the "slave" mode main
taining invariant their relative positions and orieatations during the syst
em motion. The method employs the differential displacements of the end-eff
ector of each. robot arm. Then, the differential displacements of the joint
s of the m robots are computed for the application of incremental motion co
ntrol. The algorithm was tested on many examples. A representative of them
is shown here, concerning the case of three STAUBLI RX-SOL robots similar t
o 6-dof PUMA robots. The results obtained show the practicality and effecti
veness of the method, which, however, needs particular care for completely
eliminating the cumulative errors that may occur.