We have developed a teaching system based on the assumption that the assembly task is a series of operations for achieving a target contact state among objects through changing their contact states. The features of this system are as follows:
1) teaching data for fine motion is extracted from a demonstration by an operator in a virtual world,
2) the operator can edit intermediate expressions (based on contact states) on a display,
3) intermediate expressions can be used by any robot system with a skill library which has the ability to achieve the corresponding contact states.
The teaching process of the system is as follows:
1) while an operator accomplishes the assembly motions of an object in the model world, a sequence of contact states is automatically extracted from the motions,
2) the system generates robot programs (e.g., robot programs for hybrid position/force control) by using the sequence of contact state transitions,
3) the system achieves the assembly motion in the real world.
Fig. 1 Teaching by Demonstration in VR
