25 September 2007, 01:54 by mark hoekstra

RFID racket reader

First of all, the context of this project. This has been my contribution to Mediamatic‘s RFID & Physical Computing Hackers Camp for the upcoming Picnic conference / festival.

I was asked to join this camp and a few days before I really should get going Willem Velthoven asked me if I could build/make something like this:

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...but then for RFID-tags instead of metal (that’s a metal detector on the picture, if you hadn’t spotted that already)


Well, the average (Dutch?) person carries around two to three of these tags on his/her body at the moment and you can really ask yourself (and/or the person involved) if anyone really grasps what is going on here. So, to make you/me/the carrier of these tags aware of these tags (before this project I only asked myself once if my public transport discount card was carrying such a tag and yes it does) a RFID body scanner would be a pretty handy device, eh? ^_^

my public transport discount card with an RFID tag inside
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Well, I kept Willem’s idea alive by thinking in the exact same visual way and ended up getting myself some old tennis rackets. ^_^

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...which I painted black at home and took with me to Amsterdam.

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For everyone who has worked in conditions like this (or maybe it’s just me), sitting on a table in a nice, but not your own environment and all you need is result, well… somehow not everything works out as expected. ^_^

I already had the rackets (which could still use some more paint) and we were handed SonMicro RFID readers which connect to USB. So all I needed was a beep or such when seeing a tag. But, this was last sunday, with all the stores closed for hardware I dediced to work on what was available and in my case that was …an alarmclock. I somehow spend a whole lot of time in getting this alarmclock to do what I wanted it to do, but in the end it only became some sort of hilarious setup which I’d rather not have in my bag when going through airport security.

Here it is:

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After this I decided to call it a day and take the rackets with me, to paint them a few more times during the night. Maybe it’s Amsterdam or I don’t know what got in me, but somehow the artist in me was alive and I made this to have a construction to paint the rackets and not having to worry if they would stick on the paper. ^_^

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and a proper pic for some proper art *ahem* *^_^*

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back to the subject

Anyway, I needed these rackets to be finished and on monday I got myself some decent beepers and buzzers. Now these RFID readers don’t read tags when you simply hook them up to 5 volt USB-power. They still need to get a ‘seek tag’ command somehow. There were also a lot of Arduino boards present and it would’ve been possible to shortcut the reader to serial output, feed that to the Arduino and have that issue a ‘seek tag’ command.

But, in the end we decided these rackets would be more valuable to simply use them as proper RFID readers in Willem’s other project, RFID skimmers. In a standalone mode (which was the general idea) the data isn’t collected and with the drawback that these rackets need to be hooked up to a laptop before they work, you also gain a lot of possibilities in data collection and whatever you want to do with that.

So, in the end I connected a transistor to one of the leds on the reader and soldered an extra wire to the 5 volts USB-power and this way I had a switched 5 volt powersupply for the buzzers and the beepers (simple does it eh?).

One of the rackets is outfitted with this siren kit but the siren doesn’t make a lot of noise. The other ones are outfitted with car-alarm like buzzers which make a terrifying loud noise.

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some close-up pics:

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and the racket in action! ^_^

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Well, what can I say? The rackets work, that’s for sure, but somehow I expected them to be(come) much more complicated and I’m not sure what to think about that, to be totally honest. Even though I had to leave Picnic before it even started, I’m curious if this RFID skimmers project will succeed and if so, if these rackets find a way there.

I really cannot judge and/or do not wish to think about if these rackets contribute to some RFID awareness. The only thing I know is that I had a great time and it made me more aware of RFID tags in (almost) every wallet nowadays.

project page over at the Mediamatic site


It seems that the racket is presented as a project on its own on picnic, nice!

picture credit: mark wubben
click to go to the corresponding pic on flickr


  1. Gautam @ 26 September 2007, 07:06 :

    The idea looks good to me, i would say a very well attempt!!

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