Virtual object sizes for efficient and convenient mid-air manipulation

It has been taken for granted that the sizes of virtual objects affect the efficiency and convenience of mid-air manipulation in immersive virtual environments. If a virtual object is too small or too large, for example, manipulating it becomes a difficult task. Nevertheless, the virtual object sizes that are optimal and convenient have rarely been studied. In this paper, we select a virtual object with many distinct geometric features and conduct user studies via docking tasks. Through the user studies, the optimal and convenient sizes for mid-air manipulation are estimated. In order to verify the results, a proxy-based manipulation method is designed and implemented, where the proxy is created with the estimated optimal size. The test based on the method shows that the optimal-size proxy enables users to manipulate efficiently virtual objects and the estimated range of convenient sizes is also preferred by the users.