Force fields in the manipulation of flexible materials

Assembly operations that involve flexible parts differ greatly from rigid-part assembly due to the capacity of the parts to comply with motions of the manipulators by yielding to the contact forces. This natural compliance can be exploited in the design of tasks involving the manipulation of flexible loads. Namely, using knowledge about the force vector field generated by conservative restoring forces of the load, a trajectory for the manipulator end-effector can be specified. The idea is illustrated through two case studies: an analysis of the problem of bending a flexible sheet, and experiments on an insertion task where a flexible beam has to be inserted in a hole with friction in the direction of insertion