Parallel process decomposition of a dynamic manipulation task: robotic sewing

Parallel decomposition of manipulation tasks that involve interaction with a dynamic environment is investigated. A methodology for developing concurrent process controllers for such tasks is outlined. A concurrent process control system was developed for a robotic sewing cell that produced an edge seam on a fabric panel with arbitrary edge curvature. Although a conventional sewing machine sewed up the fabric, a robot arm manipulated the panel to modify its orientation and control fabric tension. The sewing task was decomposed into four concurrent processes within a superposition parallel architecture. Although each process was based on simple linearized models, the complete system demonstrated robustness to the unpredictable dynamic behavior of the fabric panel.>