Haptic Interface Technique in Large-Scale Virtual Environment

Abstract

Haptic interface uses an electro-mechanical feedback device which enables a user to touch, feel, and manipulate virtual objects. Incorporating haptic interface into the CAD modeling system provides the user with more realistic experience. The authors have developed a freeform modeling system, which integrates haptic interface with large-scale PowerWall Virtual Environment (VE). The haptic device has very limited physical workspace. For example, the PHANToM Omni used as haptic device in the system has the workspace of 6.4 W x 4.8 H x 2.8 D in. The PowerWall is a single, flat, large-scale stereoscopic screen with the size of 10 ft by 7.5 ft. There is a mismatch between the workspace of the haptic device and the large size of PowerWall virtual environment. Some solutions have been developed to address this issue, such as the scaling technique developed by Fischer and Vance, the clutching technique proposed by Johnsen and Corliss, and the Bubble technique proposed by Dominjon et al. The haptic workspace moving algorithm was developed to solve the workspace mismatch problem. The technical contribution of our work lies in the following. Compared to the methods abovementioned, our method is easy to operate and has high efficiency. In our method, the user can move the haptic workspace by two convenient ways. The user can drag the haptic workspace to the desired location by holding the stylus button on haptic device.