Anchor placement in indoor object tracking systems for virtual reality simulations Marco Gribaudo Pietro Piazzolla Dipartimento di Elettronica, Informatica e Bioingegneria Politecnico di Milano via Ponzio 51 20133, Milano, Italy Mauro Iacono Dipartimento di Matematica e Fisica Universit` a degli Studi della Campania ”L. Vanvitelli” viale Lincoln 5 81100 Caserta, Italy KEYWORDS Indoor Object Tracking Systems; Performance eval- uation; Virtual reality; Augmented reality; Emergency response; Simulation; Fire fighting; Training; Human simulation. ABSTRACT Indoor Object Tracking Systems (IOTS) allow sens- ing moving objects inside a closed space, where GPS is not available. Besides the most popular use, indoor navigation, IOTS may also contribute to extend the operational range and the possible applications of Vir- tual Reality (VR) and Augmented Reality (AR) based technologies, such as complex training scenarios or en- tertainment oriented simulations: in fact, providing de- vices with a reliable IOTS support adds realism and allows a higher degree of safety and interactivity, that allow a high number of people to take part and col- laborate in a simulated scene with a very high degree of physical interaction. In this paper we introduce a novel approach for the optimization and the evaluation of movement tracking in a IOTS based system, oriented to VR/AR applications, with special focus on the train- ing of teams. Our proposal is applied to a case study, an AR application designed to assist business buildings workers in fire extinguisher use training. Performances of our proposal are evaluated by means of a simulation, and results are validated in a test scenario based on Ultra Wide Frequency positioning by means of a simu- lation scenario fed with real data from anchors. I. INTRODUCTION Sensing position and movement of people and things is an important problem in different application fields. While applications in open range are common and well known also in the daily experience of a wide public (GPS based navigation or logistic tracking are consid- ered commodities), there is not yet an obvious solution for closed spaces. Although it may be considered as the small scale correspondent problem, there are some specific aspects that make unapplicable the same solu- tions: typical applications are designed to work inside buildings, that are generally full of obstacles (besides the roof, that shields GPS signals, walls and objects also shield local radio emitters and there is electromag- netic noise because of the activities), involve human be- ings moving in constricted spaces (again walls, but also furnitures and objects on the floor) and require more precision (as the relevant distances are smaller). Inter- action with the environment is thus crucial to provide quality services, specially when IOTS are used to track relative movements of physical objects in the space (e.g. rotation of a stick handled by a subject moving into the environment). The precision of fine movement tracking is specially important for VR/AR applications, as they involve a physical interaction of human subjects with virtual or mixed (virtual and real) objects in a real physical space, that may be not evidently perceptible, with possible harmful consequences if the environment has to be a real context. An optimal coverage of the environment by anchors, the elements that allow posi- tion and movement sensing in IOTS, is crucial for the delivery of quality services and to enhance both the re- alism and the safety of VR/AR applications designed to be executed in real world environments. In this paper we study an optimization and performance evaluation method for anchor positioning in a IOTS. The method is demonstrated by using real anchors that feed a spe- cific simulation tool, in order to avoid experimentation with human subjects in the loop. The test scenario uses an Ultra Wide Band (UWB) radio based IOTS solution, but results can be generalized. The chosen application is devoted to the training of teams of non specialist personnel in their workplace, by means of an AR application, for a safe reaction in case of fire emer- gencies. The paper is organized as follows: in next Section we present a short literature survey focusing on indoor positioning and tracking literature. The studied sys- tem is presented in subsequent Section III, along with the description of simulation dataset. In Section IV we present the proposed methodology, the simulation approach and the results, with a discussion of the out- comes. Conclusions follow. II. RELATED WORKS Indoor positioning [7] and indoor tracking [3] are two related and interconnected (actually, partially super- Proceedings 32nd European Conference on Modelling and Simulation ©ECMS Lars Nolle, Alexandra Burger, Christoph Tholen, Jens Werner, Jens Wellhausen (Editors) ISBN: 978-0-9932440-6-3/ ISBN: 978-0-9932440-7-0 (CD)