[Cyborg] rumble vest

[Tomm]

Agreed, those are infrared sensors. This pic is pretty clear:
http://www.k2.t.u-tokyo.ac.jp/perception/HapticRadar/IMG_1452s.jpg

This is a Sharp infrared sensor:
http://www.societyofrobots.com/sensors_sharpirrange.shtml
http://www.acroname.com/robotics/info/articles/sharp/sharp.html

Given the narrow beamspread of infrared distance sensors, I would think
ultrasound would work better in the same application.  The wider
beamspread of ultrasound should mean fewer transmitters & receivers to
fully cover 360 degrees: probably just four pairs would be fine with
ultrasound.  The ultrasound transmitters I've been working with have a
90 degree,  -6dB beamspread.  Infrared is basically blind outside about
a 25 degree angle.

Ultrasound tx & rx would pick up bounces off the huge targets they use
in the video, no problem.  Driving an ultrasound transmitter also takes
much less power then infrared, but of course both would be dwarfed by
the power of running a pager motor.

    Tom

On 3/31/2010 9:04 PM, Adam Skory wrote:
> On Wed, Mar 31, 2010 at 6:32 PM, Nick Burrows
> <shamrockman at shamrockman.net <mailto:shamrockman at shamrockman.net>> wrote:
>
>
>     If they were ultrasonic, they would be stepping on each other, and
>     echos and other artifacts are more prevalent. Also ultrasonic
>     equipment tends to be bulkier than equivalent IR gear.
>
>
>
> I agree that they look like the IR sensors I've messed with, and
> nothing like the ultrasound ones. Although I will say that there are
> plenty of ultrasound sensors about that size or smaller.
>
> Also, there are ways to overcome the ultrasonic sensors interfering
> with each other by using fancy timing routines. Our brains' sampling
> rate, and not to mention the speed of motors to spin up and down, is
> much slower than the time needed for several pulse-echo sequences, so
> you really only need to run one sensor at a time. This does NOT
> however, help the problems with their super crappy range :( ... and
> you're right that there are probably lots of other artifacts to worry
> about.
>
> -Skory
>
>
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