6 research outputs found
Modellization of the spatial localization effect of the mixture dissipation on the sensitivity in a flow microcalorimeter
Response of glacial landscapes to spatial variations in rock uplift rate
The kinematics of the human hand is optimal with respect to force distribution during pinch as well as power grasp, reducing the tissue strain when exerting forces through opposing fingers and optimising contact faces. Quantifying this optimality is of key importance when constructing biomimetic robotic hands, but understanding the exact human
finger motion is also an important asset in, e.g., tracking finger movement during manipulation. The goal of the method presented here is to determine the precise
orientations and positions of the axes of rotation of the finger joints by
using suitable magnetic resonance imaging (MRI) images of a hand in
various postures. The bones are segmented from the images, and their poses
are estimated with respect to a reference posture. The axis orientations
and positions are fitted numerically to match the measured bone motions.
Eight joint types with varying degrees of freedom are investigated
for each joint, and the joint type is selected by setting a limit on the
rotational and translational mean discrepancy.
The method results in hand models with differing accuracy and complexity, of which three examples, ranging from 22 to 33 DoF, are presented. The ranges of motion of the joints show some consensus and some disagreement with data from literature. One of the models is published as an implementation for the free OpenSim simulation environment. The mean discrepancies from a hand model built from MRI data are compared against a hand model built from optical motion capture data