Agile assembly depends critically on flexible tooling including fixtures, feeders and end-effecters. There are many similarities in geometrical constraint and stability analysis between grasping and fixturing, so we treat them as one case concurrently. In this paper we present a class of novel designs of end-effecters and fixtures. Modularity, reconfigurability and reprogrammability will be a unifying trait of these novel designs. Compared with the parallel jaw grippers, our design has a rotary joint attached to each side of the grip jaw where some pegs are embedded. As a result, the grasp stability can be improved and the total grasp force can be reduced due to adding these constraint. The fixture consists of some blocks and a base. Those blocks can slide on each other, and move in order to clamp the workparts. It is enveloped and form closure in its structure. The planning algorithm is based on a generate and test paradigm. Candidate grasp configurations are generated using heuristics. The test phase involves checking each grasp configuration for force closure.
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