Accelerometer-Based Motion Tracking for Orchestra Conductor Following
In this paper, we discuss the applicability of accelerometers to measuring movement for conductor following. In our application a baton is used to conduct computer animated musicians. The user acts as an orchestra conductor. The baton motion is analyzed for gestures that imply how music and animation should be controlled. The baton motion is tracked with accelerometers. The accelerometers feature inevitable problems for position tracking. Position cannot be measured directly — it needs to be integrated twice from the acceleration. The measurement inaccuracy causes drift over time when velocity and position are calculated via integration. We used two sensors to track motion with six degrees-of-freedom. The problems can be largely overcome by using application-specific signal processing The drift caused by inaccurate integration is countered by combining leaky integrators and high-pass filters. Rotation is detected by monitoring the direction of gravity.
KeywordsMotion Tracking Infinite Impulse Response Leaky Integrator Motion Tracking System Filter Design Method
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