UWEE Tech Report Series

Polishing and Measuring Distorted Spheres for Psychophysical Experimentation


Blake Hannaford, Jesse Dosher

haptics, spheres, psychophysics, human factors, threshold


How well can people detect shape with their fingers? How accurately can they discriminate between two small shapes? To study this problem, the Biorobotics Lab will test people's ability to detect which of two spherical ball bearings is ``perfect" and which is out-of-round. An earlier report described grinding procedures for making precise distortions of spheres. The spheres then must be polished to remove surface texture cues that might confuse the experiment. This report describes polishing methods used to achieve uniform texture on the spheres, and also a system for precisely measuring the profile of a circular cross section of the distorted and polished spheres.

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