Showing papers by "Leonard S. Mark published in 2004"
TL;DR: The findings indicate that Cesari and Newell's method can identify a complex relationship between geometric and dynamic constraints that determine the affordances for different reach actions.
71 citations
TL;DR: Results indicate that when subjects wore the belt while reaching, they tended to have initial transition points (sitting to nonsitting) closer to their bodies than while not wearing the belt, possibly acting to preserve a greater margin of safety.
3 citations
01 Sep 2004
TL;DR: In this paper, the type of reach action used to pick up the object was categorized in an effort to demarcate reach envelopes for different reach actions and identify the directional location in the workspace at which people change from reaching with their right hand to using their left hand.
Abstract: Geometric models of normal working area have been derived from analyses of theoretically possible, but contrived and restrictive arm and hand movements (Farley, 1955; Squire, 1959; Wang et al., 1999). It is unclear whether the resulting boundaries delimit a safe, comfortable and effective reach area. The goal of the current investigation was to obtain data that can establish reach boundaries that reflect actions that are both comfortable and efficient. Adults reached for objects placed in various directions and distances in front of them. The type of reach action used to pick up the object was categorized in an effort to demarcate reach envelopes for different reach actions and identify the directional location in the workspace at which people change from reaching with their right hand to using their left hand. These data showed that people's reach actions violated important characteristics of the geometric models, including the spatial symmetry in the use of the right and left hands. From these data we a...
1 citations