Abstract
This paper proposes an overview of a study that conceptually unify the fields of virtual reality and tele-operation, by analyzing the notion of “assistance” to the operator of a virtual reality or tele-operation system. This analysis demonstrates that cases of assistance that are usually considered to belong to virtual reality are not conceptually different from what has been done in tele-operation since long before virtual reality appeared. With this common framework for virtual reality and tele-operation, we hope to provide a theoretical formalization of many ideas acquired empirically, and hence a basis onto which further discussion could be undertaken in a constructive manner.