INTRODUCTION: This paper describes an advanced skiing Simulator, which is currently in the design phase. The purpose of the Simulator is to simulate, as close as possible, the visual and kinesthetic sensing during alpine skiing. METHOD: The system overview is presented in Figure 1. The movement of the skier is captured using the motion tracking system. Based on skier's motion and virtual environment, an accurate full body dynamic model is calculated on line, The visual sensing is calculated in virtual reality model and reproduced through a 3D virtual reality helmet. The kinesthetic sensing is archived through the motion of four degrees of freedom platform, capable of motion in Z direction and in all three orientations. Unfortunately, the platform is not capable of handling high forces due the radial acceleration during the ski turn. For this purpose, two methods were evaluated - using EMG muscles Stimulation - using exoskeleton, which applies resulting forces to the lower extremities of the human body. RESULTS: Virtual environment was realized in BLENDER, which was originally developed as a game development environment, but has all the capabilities required for an advanced virtual reality Simulation tool and is currently being used in robotics, as well. Video Images of the virtual environment from the skier's view point were sent to the Video glasses with 30Hz rate. Ski slope was captured using the GPS measurement system. For the motion tracking system, we evaluated MOVEN tracking System, which was able to accurately track the human motion on line. The captured posture was fed to the human body dynamics model, which calculated external forces acting to the body segments. Dynamic model was realized using SDFast tool, which generated C source program code. External forces were used to drive the 4 d.o.f platform. Since the platform is not capable of reproducing high forces, two methods were evaluated - using exoskeleton, which compressed both knee joint, and EMG Stimulation of the flexor muscles. DISCUSSION: A!l components of the system, except the 3D platform, were developed and tested, the results are satisfactory. The platform is currently in the design phase. The EMG Stimulation gives appropriate compression force, but the feeling is unpleasant, sometimes even painful. Therefore, an appropriate exoskeleton device is still under investigation. CONCLUSION: The paper describes an advanced skiing Simulator. Although the Simulator is still in the design phase, most of the components were evaluated. It is expected that it will outperform all existing skiing Simulators.
© Copyright 2007 4th International Congress on Science and Skiing. Veröffentlicht von University of Salzburg. Alle Rechte vorbehalten.