Correcting Drift, Head and Body Misalignments between Virtual and Real Humans

Abstract

Head-mounted displays (HMD) allow a personal and immersive viewing of virtual environments, and can be used with almost any desktop computer. Most HMDs have inertial sensors embedded for tracking the user head rotations. These low-cost sensors have high quality and availability. However, even if they are very sensitive and precise, inertial sensors work with incremental information, easily introducing errors in the system. The most relevant is that head tracking suffers from drifting. In this paper we present important limitations that still prevent the wide use of inertial sensors for tracking. For instance, to compensate for the drifting, users of HMD-based immersive VEs move away from their suitable pose. We also propose a software solution for two problems: prevent the occurrence of drifting in incremental sensors, and avoid the user from move its body in relation to another tracking system that uses absolute sensors (e.g. MS Kinect). We analyze and evaluate our solutions experimentally, including user tests. Results show that our comfortable pose function is effective on eliminating drifting, and that it can be inverted and applied also to prevent the user from moving their body away of the absolute sensor range. The efficiency and accuracy of this method makes it suitable for a number of applications in immersive VR.