Enhanced hand manipulation for efficient and precise positioning and release

Abstract

Direct manipulation by hand is important in that it allows users to manipulate 3D virtual objects easily in an immersive virtual reality environment. Although direct hand manipulation is easy to understand and easy to use for approximate positioning, it has been considered unsuitable for making precise adjustments to virtual objects in an immersive environment because it is difficult to hold an unsupported hand in midair and then release an object at a fixed point. This paper therefore proposes automatic methods of adjustment to position and release virtual objects precisely. These methods are position adjustment, virtual hand size adjustment, viewpoint adjustment, and release adjustment. Combinations of these adjustments enable users to accurately manipulate virtual objects. Experimental evaluation revealed that release adjustment significantly increased the completion ratio for tasks and subjective preference for small targets.