Have you ever thought of a RFID reader product? The antenna coil may be a bit of a manufacturing challenge but not an impossibility. It wouldn’t have to be anything to advanced. A single tag read only unit would be great for carying on a mobile robot with tags scattered arround in known locations for positioning assistance.
Just a thought.
–adam
This is a interesting project, somone turned a disposable camera into a RFID zapper, interesting artical:
kinema:
The antenna coil may be a bit of a manufacturing challenge but not an impossibility.
Grand Idea Studios designed a 125Khz reader which is sold by Parallax. The antenna is part of the circuit traces.
with tags scattered arround in known locations for positioning assistance.
Using IR beacons could present a more cost-effective solution. The cost of the transmitter would be close to the cost of a passive RFID tag (at today’s prices), and the cost of the receiver would be substantially cheaper. A passive RFID device wouldn’t require power, but a beacon could be designed to be interrogated by the robot thus preserving battery life. An IR beacon would also have a larger range than a passive RFID tag (feet versus inches).
Have you ever thought of a RFID reader product?
An inexpensive reader that uses the “SpeedPass” type tags would be a welcome addition. I have an access control system using the Parallax reader. The Parallax tags are on the large size, but managable. What I would like to do is drop readers all over the home, so I can use one tag to unlock doors, access my PC, etc. At $40 a reader, the cost isn’t out of the question, but is sure would be easier to get approval from upper management (my wife), if it could be done less expensively. 
Legal Concepts:
This is a interesting project, somone turned a disposable camera into a RFID zapper, interesting artical:
This could be developed into a family of products: a reader, the RFID tags, and a tag Zapper. Chances are I wouldn’t get everything correct the first time around, and I would have to order more tags for testing (and maybe a new reader if I was extremely careless). I think you’re on to something here! :lol:
the 125khz readers are fairly cheap on ebay. if you buy them new from a disti, they are upwards of a hundred dollars but I picked up several around 20 each. The tricky part isn’t reading the tags but networking the readers and setting up a database. I have 3 readers that i use for access control at my house but the system is clunky. I’ve designed a 4 reader controller that will eventually replace the existing piece of junk.
herfing tags would require emissions above the fcc unlicensed limits so be careful what you do. I suspect the feds would be very anxious to prosecute for more than just an FCC violation and businesses would be very ready to sue. I bet the manufacturers of tags would beef them up to be herf resistant.
I would like to see a reader detector/jammer. It would be a powered “tag” that is more sensitive than the passive ones and would over whelm a passive tag’s response. I’m sure that would eventually get outlawed