Using configuration and force sensing in assembly task planning and execution

A geometric trajectory ensuring the success of an assembly task cannot be determined when the geometric uncertainty is significant. Several solutions like, for instance, passive compliance devices have been applied in order to decrease the influence of geometric uncertainty. However, the general solution appears to be the use of active compliance which implies reaction force/torque feedback, but this use gives rise to some particular problems in the task planning and execution. Sensorial configuration and force information becomes a key point in this field. This paper describes how this sensor information can be used in an assembly fine-motion planner and also during the task execution. The basic concepts have already been implemented and the peg-into-hole assembly task serves as an example to illustrate the results