Real-time motion scheduling for a SMALL workcell

Abstract

A high-level controller for a SMALL workcell (Sawyer-motor assembly workcell) is presented. It allows multiple independent process to share the robot modules and workspace of a single workcell, by planning and scheduling collision-free paths for module motions in real time. Planning may involve moving around other modules, stationary or in motion, waiting for motions to complete, or displacing obstructing idle modules. The controller handles any number of robots in simultaneous motion along paths consisting of multiple rectilinear segments. Collision avoidance and path-planning are addressed in two dimensions, with extensions to three dimensions briefly discussed. Design considerations for the algorithms involve throughput, protection, fairness, and starvation considerations. Capabilities to allow independent processes to cooperate without interference are provided.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>