Much Ado About Ants
We all know that ants are exceedingly strong for their
size, with the average one being able to lift as much as 50
times its own body weight. This isn't all that amazing, given
that — as a matter of physics — smaller organisms will
always have a higher strength-to-weight ratio than larger
ones. However, a group of engineers at Ohio State's Ohio
Supercomputer Center ( www.osc.edu) recently
determined that a major factor in any ant’s ability to drag
home a dead bird is their neck — a single, flexible joint that
bridges the head and thorax exoskeletal units.
To figure out how and why the little necks are so
strong, they attached some ants heads to a centrifuge and
spun them around until their necks snapped and their
bodies went flying against a Plexiglas barrier. They also
created 3D models of the ant’s anatomy by importing
cross-section images of the specimens into a modeling
program running on the OSC Oakley Cluster (based on
8,300 Intel Xeon processor cores), and came up with a mesh frame model containing more than 6. 5 million
elements. The experiments revealed that the neck joints can withstand loads of up to 5,000 times the insect’s body
weight. It doesn't appear that this revelation has any immediate practical application, but according to Vienny
Nguyen, a co-author of the paper on the subject, "As we look to the future of human-assistive devices and ultra-light robotics, the development of 3D models for visual analysis and loading and kinematic simulation will also serve
as tools for evaluating and comparing the functional morphology of multiple species and types of joints."
Computer-generated mesh frame model of an ant's neck.
by Jeff and Jenn Eckert
Hands Off the Merchandise
Let's say you're a medical student learning to palpate human breasts to check for lumps. Let's also say that for some
reason you are squeamish about touching the real thing or even a silicone model of the real thing. Ignoring the fact that
you're obviously weird and emotionally unequipped for a medical career, you're in luck, as researchers at Japan's Gifu
University ( www.gifu-u.ac.jp) have created the "multi-fingered haptic interface robot" which will allow you to avoid icky
contact with other human beings. The device — when attached to your hand — "can simulate the softness of different
materials by producing realistic tactile sensations on individual fingertips."
The secret of the device's effectiveness is a thin flexible sheet of "hyper-gel," said to feel similar to human flesh.
The gel is stretched by two small rollers with a gap
between them, thereby suspending the gel strip.
Using motors and a set of gears to move the
rollers, the gel strip's tension is increased or
decreased, thus making it feel harder or softer to
Reportedly, the researchers "plan to conduct
more experiments, and hope that their hardware
will prove accurate enough that it can one day be
used to replace humans and animals for significant
portions of medical training, mitigating issues of
availability and ethics, and becoming a valuable tool
for training future physicians in the use of touch."
Silicone breast model and fingertip haptic
device used in an experiment.
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