Abstract: In this talk, Dr. Provancher will describe two novel approaches to
providing haptic guidance for navigation and fine motor tasks. These
two approaches are: (1) applying tangential skin displacement to the
fingertip for providing direction cues; and (2) augmenting a
traditional stylus-based haptic interface with an Active Handrest. An
overview of each of these areas is provided below.
Direction Cues via Tangential
Fingertip Skin Displacement
Dr.
Provancher’s lab has conducted initial perceptual studies to better understand
how best to communicate direction via tangential skin displacements applied to
the fingertip. This type of tactile feedback is accomplished by coupling the
user’s finger to the tactile feedback device and then applying skin stretch to
their fingertip using a 7 mm diameter rubber contact block (tactor). A number
of variables in applying this type of feedback including the magnitude and
speed of the tactile stimulus, its motion profile, and the tactor’s geometry
and texture have been explored. The results of these experiments along with work
towards miniaturization of these tactile feedback devices will be presented and
discussed.
An Active Handrest for
Precision Manipulation and Ergonomic Support
The
goal of the Active Handrest is to take the relatively limited precision
workspace of the human hand and to extend this over larger workspaces. The
Active Handrest would benefit surgeons and other medical personnel, artists,
machinists, workers performing pick-and-place tasks, or anyone requiring
dexterous control of tools.
Our current prototype Active Handrest is a
planar, computer controlled support for the user’s wrist that allows the user
complete control over a grasped tool. The device uses force input from the
user’s hand, position input from a grasped manipulandum, or a blended combination
of both force and position inputs. The control algorithm of the device then
interprets and converts the input(s) into handrest motions. Our initial studies
have looked at the effects of control input type and velocity limits on task
precision and completion time. These results were also compared to performance
under fixed hand/arm support conditions. The results and insights from these
experiments will be presented and discussed.