Scheduling and compression for a multiple robot assembly workcell

Abstract

A scheduling and compression strategy is presented for a multiple robot assembly workcell. Based on dynamic programming, the algorithm gives an initial assembly sequence for a two- or three-robot cell with a common resource or dedicated ones. The initial assembly sequence is computed efficiently, with computational complexity of being O (log n/k) where n is the number of elements in k resources. Then the initial sequence is further compressed towards the time-optimal assemblysequence. Precedence constraints in assembly are considered. The scheme is tested using computer simulations and some test results are presented. For the problems solved (typically involving 20 elements), the computational times were less than 5 seconds in an Apollo 300 workstation.