

Advanced RFID with Arduino and Python - dawsdesign
http://appdelegateinc.com/blog/2010/10/06/rfid-auth-using-arduino-and-python/

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beambot
There are some really great open-source Python libraries for UHF RFID tags
(battery-free tags that can be read from 6+ meters away):
<http://www.ros.org/wiki/hrl_rfid>

These form the basis of my PhD work. Turns out you can do some cool stuff when
you couple it to an autonomous, mobile, manipulating robot:
[http://www.hsi.gatech.edu/hrl/pdf/pervasive_computing_2010.p...](http://www.hsi.gatech.edu/hrl/pdf/pervasive_computing_2010.pdf)
(PDF)

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tassl
A couple of questions... How do you get rid of the signal rebound due metallic
presence in the robot?

 _provides an object a unique ID with extremely small uncertainty, whose
location is inferred by lowerlevel sensory processing_

How precise is your method to locate the object? Are you using an array of
antennas to calculate the position of every RFID?

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beambot
Multipath due to the robot's body is certainly a design issue. Generally, you
try to use highly directional antennas facing away from the robot so that the
influence is minimized.

The particle filter implementations for localization use the motion of the
robot or panning antennas to integrate the otherwise sparse signals into
something more meaningful. This is analogous to using an antenna array. Still,
with these implementations (under the best conditions), you're talking about
an error of ~20-50cm on average with a pretty high variance -- meaning other
sensors are generally required, though our near-field antennas allow you to
hone in on the position even better using the same tag.

Meanwhile, local methods (eg. servoing from the difference between two
antennas) works quite well. Publication(s) forthcoming. ;)

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arohann
The Arduinos are great. I have two of them. One is a DIY clone called
"DorkBoard". Check it out. Also have a look at the MSP430 based LaunchPad kit,
its very cheap and available from Mouser.com.

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dawsdesign
Yeah, I have 4 MSP430's, but they're a little tougher to program

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dawsdesign
Advanced features, but easy to use.

