Transporting objects and manipulating tools requires that properties such as size, shape, and orientation be perceived so that activity can be guided effectively. If vision is absent or simply directed elsewhere, are environmental properties revealed in the tissue deformations that accompany wielding with the hand or exploring with a hand-held object such as a cane?
Here is the problem: Muscular forces and object motions vary over time but the properties do not. Our work focuses on time-invariant quantities–moments of the mass distribution–that have been shown to underlie haptic perception of a variety of functional properties of objects, properties that reflect how an object can be moved and controlled. Experiments involving manipulations of the mass distribution examine spatial capabilties of dynamic touch and allow comparisons to the informational support for vision and hearing.