Mechanics for Robot Hands and Arms
use even on the tightest robot
construction project where a robot’s arm
needs a bit of help overcoming gravity.
Final Thoughts
FIGURE 10. A
$20 desk lamp
that can defy
gravity.
FIGURE 9. x-Ar
by Equipois.
other apparatus beside the worker. The x-Ar is not powered
like a complex exoskeleton, but uses simple springs to
compensate for expected loads. The use of this simple
device makes even more sense to use if only a single arm is
required. The x-Ar is positioned on the dominate arm of the
user — the one he/she would normally use in the repetitive
assembly operation.
In our homes, we may have a desk lamp over a
workbench or drawing table like the one shown in Figure
10 that has a series of parallel steel rods at several hinge
points and some compensating springs. At less than $20,
this gravity-compensation technology is not too expensive to
Arms add a special human touch to
robots; even more so with hands. Using
a mechanical technique to improve your
robot’s ability to lift a payload, is not
only cheaper than the use of a motor,
I encourage all of you who may want to explore the
addition of arms and hands to your creations to look at
simple mechanical means to assist these appendages. If a
wild mercenary of 500 years ago could do it, imagine what
you can do with today’s mechanical technologies. SV
shaft encoder, or necessary
microcontroller control software, but
draws no extra power from a limited
power source. Go through your junk boxes and pull out
those coil springs and gas springs, rods, hinges, or
whatever, and just sit down and piece together a
masterpiece for mechanical buddy.
Tom Carroll can be reached at TWCarroll@aol.com.
80 SERVO 09.2011
