Interacting and cooperating beyond space: Tele-maintenance within a virtual visual space

This paper describes an innovative concept and implementation of a maintenance system enabling tele-cooperation of distributed technical personnel. It provides a synchronous shared visual workspace in remote locations with limited bandwidth. A mechanic at the remote location uses an Augmented Reality (AR) system which is connected to the Virtual Reality (VR) system of an expert at the homeland. The expert interactively creates 3D instructions on his VR system that are displayed on a ruggedized hand-held tablet computer of the mechanic. The mechanic considers and follows these instructions during his maintenance work. In addition he can interact in real time with the live AR view creating spatial references for the expert. The system has been evaluated by 18 experienced automobile mechanics, 6 of them technical soldiers of the German army. The maintenance task consisted of the disassembly of the camshaft housing of an internal combustion engine. The results show clearly that participants completed significantly more tasks and used less verbal instructions when using the VR system compared to a video system. Thus, performance was increased by the system. In the paper we will detail the concept, give an overview of the implemented system and present the results of the practical evaluation.