Rosenberg's 1993 article Virtual Appliances: Perceptual Tools for Manipulating Tele-Robots Explain What It Is and the Protocol that he used as an application.
If you cannot access this article, I will briefly outline this idea, and I think there is no harm in showing photos here from Rosenberg.
The idea is that the user puts on an exoskeleton to complete the task from operator space to the remote environment. In addition, either the exoskeleton or physical objects (on the instrument board) restrain possible movements of the operator’s hand, just as the physical ruler limits the movement of your pencil (so you can draw a straight line faster and with greater accuracy). The difference between a virtual device and a ruler is that the virtual device does not physically exist in the remote environment , that is, where the task is actually completed (it can exist in the operator’s space), but you still get its tactile (sensory) feedback. For example, as if the surgeon could have a ruler during the operation, but for the obvious reason, you cannot physically put this ruler through the patient’s body.
In addition (this is an innovative part of augmented reality), virtual lights can be displayed on top of the real world using a composition of real images and visualized virtual lights. Therefore, you not only feel them through the exoskeleton or the actual ruler, but also see them through the vision system, so this increases your feeling that the device is indeed present in a remote environment, even if they do not physically exist there. An example of the fixtures (planes) used is given below:
In general, these fixtures help the user to perform a different task, giving him greater accuracy, in the case when the physical ruler cannot physically share the space where the task is actually performed.
The conclusion of the article:
The results confirm that the imposition of abstract sensory information in the form of virtual luminaires on top of sensory feedback from a remote environment can significantly increase the operator’s productivity. virtual luminaires, consisting of simple combinations of impedance surfaces and abstract audio information, increased operator productivity by up to 70%. An analysis of some basic elements of perception suggests that virtual lights enhance perfectionism, simplifying the perception of the workspace, changing the conceptualization of the task, providing localization of links to the remote desktop and requirements for taxable sensory modalities by providing information through alternative sensory paths. Surveys showed that the use of virtual lights led subjects to change their conceptualization of the task so that a successful trial would no longer just look a certain way, but also feel a certain way and a certain way.