Balloon Selection: A Multi-Finger Technique for Accurate Low-Fatigue 3D Selection

Balloon selection is a 3D interaction technique that is modeled after the real world metaphor of manipulating a helium balloon attached to a string. Balloon selection allows for precise 3D selection in the volume above a tabletop surface by using multiple fingers on a multi-touch-sensitive surface. The 3DOF selection tasks is decomposed in part into a 2DOF positioning task performed by one finger on the tabletop in an absolute 2D Cartesian coordinate system and a 1DOF positioning task performed by another finger on the tabletop in a relative 2D polar coordinate system. We have evaluated balloon selection in a formal user study that compared it to two well-known interaction techniques for selecting a static 3D target: a 3DOF tracked wand and keyboard cursor keys. We found that balloon selection was significantly faster than using cursor keys and had a significantly lower error rate than the wand. The lower error rate appeared to result from the user´s hands being supported by the tabletop surface, resulting in significantly reduced hand tremor and arm fatigue.