Virtual reality based time and motion study with support for real walking

Abstract

Manual operations in mass production are important cost drivers. Thus, tools like the MTM (Methods-time Measurement) – a time and motion study method – were introduced, which are nowadays established in industry for evaluation and improvement of production facilities. In this method, cardboard engineering is used to build simplified physical mock-ups of machines or production lines, in which the manual working process can be simulated. However, new strategies like e.g. decentralized production require the worker to walk, which is not well incorporated in the MTM and times are only estimated from the walking distance. Since many workplaces, machines or production lines already exist as digital models, it is obvious to perform the MTM completely virtually. However, this comes at the cost of a complex handling and strongly reduced realism because a desktop-based MTM application does not allow natural navigation – like walking – within the full-sized models like the cardboard setups do. This paper introduces a virtual reality-based MTM that also allows for real walking in virtual factories without using a treadmill or other walking devices. With a subtle redirection of the user during walking, these virtual factories can even be larger than the available physical space. Hence, a realistic measuring of walking times and distances can be done instead of an estimation. Since the MTM can be completely performed within a virtual environment, it gives a new realism to the method compared to the cardboard procedure. The paper closes with an outlook on future work and extensions of this novel virtual MTM.