Research On Indoor Positioning Technology Of Large-scene Immersive Virtual Reality Game

With more and more wide applications of wearable devices, immersive virtual reality(VR) head-mounted display has become one of the focus of concern. Although immersive VR has been used in construction, tourism, gaming and other industries, visual effects of some human behaviors, such as human walking and interacting displacement, is not satisfied because of limitations on the head-mounted display function.Based on monocular-vision-based indoor positioning technology and head-mounted display, the work of this thesis aims to achieve good synchronization displacement effect in the virtual space and real space. As described in the following, the research uses ARToolKit library as positioning basis, and focuses on improving accuracy and decreasing time for positioning, so as to meet the synchronous interaction requirements of displacement in VR.Firstly, to decrease the number of the positioning marker for monocular machine vision indoor locating system, a layout method of marker is proposed. This method firstly designs the layout of marker for monocular machine vision indoor locating system. Then, according to the indoor scene and the camera, it realizes indoor positioning for big scene by using marker as less as possible. Theoretical analysis and experimental results both demonstrate the validity of this method, and prove that can effectively reduce the refresh time.Secondly, since the area of the marker in the image has reduced when ARToolKit library is extended from the desktop to the big scene, and localization algorithm is not precise on the corner detection and positioning, solutions are proposed. For the problem of corner detection, a corner detection algorithm of positioning marker is put forward based on dynamic corner response template. The algorithm improves the accuracy of corner detection, because it further uses the sub-pixel detection on the basis of ARToolKit corner detection. In order to solve the problem that it will produce a large error when the optical axis of the camera is not perpendicular to marker plane, a location algorithm is put forward based on Oculus Rift 2 angle data, which makes positioning result greatly improved. At last, Gaussian filter is applied on positioning data for denoising, so the improved ocalization algorithm in great scene of VR achieves centimeter-level accuracy, and meets the requirements of the synchronous interaction of displacement in VR.Thirdly, a great scene immersive VR system is designed and completed based on the above researches, and this system has the function of the synchronous interaction of displacement in VR. The experimental platform has the indoor positioning module developed on the basis of ARToolKit library, and Virtual rendering module developed on the basis of Oculus SDK. Finally, the system is displayed on the Oculus Rift 2 Head-mounted display.