Pointing with fingers, hands and arms for wearable computing

Pointing is a fundamental enabling operation for human-computer interaction across a broad spectrum of scenarios. The paper presents a study exploring how to develop a pointing system for truly wearable, rather than hand-held, computing. It describes a Fitts' law study of pointing based on motions in free-space captured using an inertial sensor pack. It compares performance when the pack is held in the hand, mounted on the back of the hand and finally on the wrist. The results show a significant, but numerically small, advantage in using the hands over using the upper arm only. This suggests that for wearable tasks where pointing is relatively infrequent a wrist based sensor pack may well be sufficient to enable effective and usable interaction.