Virtual Reality supported Visualization and Evaluation of Noise Levels in Manufacturing Environments

Virtual Reality supported Visualization and Evaluation of Noise Levels in Manufacturing Environments∗ Xiang Yang1 , Bernd Hamann2 , and Jan C. Aurich1 1 Institute for Manufacturing Technology and Production Systems (FBK) University of Kaiserslautern, Germany Institute for Data Analysis and Visualization & CS Department University of California, Davis, USA 2 Abstract Virtual Reality (VR) provides users advanced visualization and interaction technology for designing, analyzing and exploring complex data. To address the issue of noise in manufacturing environments, we developed a VR-supported method allowing users to explore noise behavior. This method consists of an implementation of acoustic simulation and visualization for both desktop and Cave Automatic Virtual Environment (CAVE) based VR systems. It enables useroriented, interactive analysis of simulated data, where there capability to immerse oneself in the data is especially valuable. In a real-world factory, the acoustic measurements obtained essential input data for simulation settings and validation data for simulation results. Furthermore, some political and legal aspects are addressed to enhance the evaluation of results and the visualization. By using the implemented software tool, users are able to understand and investigate the noise issue in manufacturing straightforwardly. 1998 ACM Subject Classification J.6 Computer-Aided Engineering Keywords and phrases virtual reality, acoustic simulation, visualization, manufacturing Digital Object Identifier 10.4230/OASIcs.VLUDS.2011.1 1 Introduction 1.1 Virtual Reality The Virtual Reality (VR) is applied in this paper to support the investigation of noise issues in manufacturing industry. With a virtual environment, the acoustic simulation and visualization are implemented. The simulation results and enhanced analysis capabilities in VR provide a new point of view to fulfill this special requirement during factory planning. As a comprehensive and widely developed technology, VR is originally defined as: „a system that can display information to all senses of the user with an equal or bigger resolution than the one that can be achieved in a natural way so that the user cannot say that the artificial world is not real” [24]. In recent years the VR technology is improved significantly by increasing demand of industrial applications and shows following changes, such as increased hardware power, reduced acquisition costs, integrated methods with simulation and visualization. And on ∗ This work was partially supported by Eduard Deines, Simon Schröder and Tim Biedert. © Xiang Yang, Bernd Hamann, and Jan C. Aurich; licensed under Creative Commons License ND Proceedings of IRTG 1131 – Visualization of Large and Unstructured Data Sets Workshop 2011. Editors: Christoph Garth, Ariane Middel, Hans Hagen; pp. 1–12 OpenAccess Series in Informatics Schloss Dagstuhl – Leibniz-Zentrum für Informatik, Dagstuhl Publishing, Germany 2 VR supported Vis. and Eval. of Noise Levels in Manufacturing Environment implementation level, the Virtual Reality Modeling Language (VRML)/Extensible 3D (X3D) standard is widely used and further developed. The VRML standard is originally developed as a modeling language for web applications and later accepted by the International Organization for Standardization (ISO) [2]. It is implemented for different applications, e.g. virtual assembly, machining processes simulation, visualization of facilities, and employee training parallel to the running production [17, 10]. Some web-based applications are also found in literature review. For example, Qiu et al. demonstrate an implementation of automation animation using VRML and identified fundamentally their advantages like assembling CAD-objects and their interaction [19]. And remarkable of Ranga and Gramoll [20] are the introduction and implementation of JavaScript into VRML and the performance in 3D FE-analysis. They realized a web-based virtual environment and included a customized user interface. As successor to VRML, X3D is also standardized by ISO and contains mostly all VRML features. For current applications X3D has no remarkable advantages comparing VRML. On the other hand, VRML has more developed Nodes, APIs and extensions. With Java or JavaScript, different programming solutions like mathematical descriptions can be implemented in VRML. The Nodes offer a customized link to different positioning and allocations between different objects. Therefore, VRML is used as modeling language and scene graph standard in this paper. Due to the internet nature of VRML, in this paper a web-server based concept is developed. According to different user immersion levels, VR systems are classified into non-immersive and immersive systems. A non-immersive VR system, such as a desktop-based display system, is according to some VR definitions not understood as a real VR system. The full-immersive VR systems, such as the CAVE system, provide most costly and complex solution with unique benefits. Compared with non-immersive system an immersive VR system has higher sense of situational awareness, wider field of view, higher scale perception and sense of immersion. However, a non-immersive VR has advantages of lower costs, shorter development time, and better implementation conditions. For example, the desktop-based VRML viewer enables users implementing and viewing the developed virtual environment with simple configuration. At the Institute for Manufacturing Technology and Production Systems (FBK), we use the both VR systems to satisfy different demands of research and industrial projects [8, 9]. The proposed concept in this paper is also first developed and tested in a desktop-based environment and further in CAVE system. The implementation and visualization in both systems are to be discussed in latter sections. 1.2 Noise in Manufacturing The factory workers are exposed to any of occupational hazards every day, such as, chemical solvent, heat, noise, vibration, etc. Noise is becoming one of the most frequent occupational hazards in manufacturing. The noise in a factory could from machinery, powered tools or other activities, which influences employees’ health and can even cause diseases. According to DIN 1320 and VDI 99, the noise is described as unwanted sound causing disorder, harassment and other health problems. As the noise exceeds specific limits, the risks of hearing loss or other sicknesses are increasing. According to the investigation of Federal Institute for Occupational Safety and Health (BAUA), about five million employees are exposed to noise in Germany. And this number in USA 1991 was over six million [12]. To protect health and safety of the employees, there are existing laws and guidelines to follow, e.g. the Federal Ministry of Labour and Social Affairs (BMAS) limits noise and vibration levels within Germany’s Occupational Safety Law “Arbeitssicherheitsgesetz” (ASiG), German ordinanc (...truncated)