According to a short article
on betterhumans.com, the latest thing in android skin is the polymer
tactile sensor. Also known as "smart skin", the sensor is an
inexpensive, flexible polymer material that can conform to the shape of
the robot and provides high spatial resolution and sensitivity. Robots
with smart skin will be able to build maps of tactile contact that can
be used to detect slippage of gripped objects and shape recognition when
touching objects. Research on polymer tactile sensors is being carried
out by Jonathan
Engel at the University of Illnois' Micro Actuators, Sensors,
and Systems Group (MASS).
Looks interesting. I'm going to have a go at giving my own robot a
sense of touch at some point, and I've been wondering what type of
sensors I should use.
The sensors will be built into the fingers, palm and thumb of my robot
humanoid. I could make some kind of small switch, but I'd like to make
something which gives an analogue 0-5V signal so that the robot can
tell how much pressure is being applied to each sensor.
Anybody have any ideas?
Resistive flex sensors might work, Jameco has some. Simple voltage
divider for an analog voltage, here. Another possibility might be
strain gauges though I haven't found a low cost source of those, or
more specifics on their use.
has anyone ever toyed with a sensor similar to a touch lamp? i had an
electronics kit when i was a kid, you know the boards with the
componenets and springs? i had constructed a circuit from it one time
called a touch switch. when i touched the end of a loose wire or the
spring it was connected to, an LED would light up. i can't seem to
find this cicuit online. but i would imagine you could solder this
wire to a piece of sheetmetal and insulate it from the robot. so you
could make the robot have sheetmetal skin but in sections. when a
human touches it it will know what section a human has touched. i
think only humans could trigger the sensor but not sure. anyone know
anything about this touch switch?
I agree with the above poster.. Those resistor "bend" sensors you
sometimes see integrated into gloves sounds like a good, reliable and
inexpensive place to start.
I would run them through the A/D converter and give that a shot.
There's also a fiber optic "laser whisker" sensor outlined in the 'Robot
Builders Bonanza' book that works pretty well. It exploits a flaw in
stepped index fiber optic cables (you lose some throughput as they bend)
He then measures this up with a photo transistor and A/D to effect a
light touch sensor.
Maybe something like that?