Motion planning for multi-robot assembly systems

This paper addresses a multi-robot optimal assembly planning problem which in essence is an augmented Travelling Salesperson Problem (TSP+). In our TSP+, both the “salesperson” (a robot with a tool) as well as the “cities” (another robot with a workpiece) move. Namely, in addition to the sequencing of tasks, further planning is required to choose where the “salesperson” should rendezvous with each “city”. The use of a genetic algorithm (GA) is chosen as the search engine for the solution of the multi-robot TSP+ optimization. As an example industrial application the optimization of the electronic-component placement process is addressed. In the most generalized component-placement system configuration, the placement robots meet the component delivery systems (CDSs) at optimal rendezvous locations for the pick-up of components and subsequently meet the printed circuit board (on the mobile XY-table) at optimal rendezvous locations for their placement. In addition to the solution of the componentplacement sequencing problem and the rendezvous-point planning problem, the collision-avoidance issue is also addressed.