Flexible Assembly Through Integrated Assembly Sequence Planning and Grasp Planning

Abstract

This paper describes an assembly sequence planner able to generate feasible sequences for building a desired assembly. The assembly planner takes geometrical, physical and mechanical constraints into account. Moreover, the planner considers the feasibility of grasps during the planning process and takes into account work-cell specific constraints. The approach uses AND/OR-graphs for planning. The generation of such graphs is implemented by using a specialized graph cut algorithm that employs a dynamically changing priority queue. These graphs are further evaluated by considering the feasibility of grasping sub-assemblies and individual parts during the process. The grasp and the sequence planner are generic, hence the proposed solution can be applied to arbitrary assemblies of rigid parts. The system has been evaluated with different configurations obtained by the combination of standard item-profiles.