Arduino Uno + WiFly + ID-20 RFID Reader / Facebook RFID Like Thingy

Hello there,

First of all, I am definitely a beginner here. I have minimal hardware and software knowledge and trying to build something with a developer friend. I bought my first Arduino a year ago and since then I am trying to build the same thing from time to time..

My goal here is to confirm my workflow, parts I use and get advice.

My project goal is to reproduce the well-known Facebook RFID Like Thingy. We have developed the software, built up the hardware and everything is working almost fine. I like to be sure if this is the best way in my situation or if this workflow is stable enough.

to sum it up

We have Arduino Uno + WiFly Shield from Sparkfun + Innovations ID-20 RFID Reader + a Led running. Then written two softwares named as Terminal and Nodes. Terminal software runs on a pc with a rfid reader and a Processing application which reads the tag then pushes it to a browser to load Facebook login to pair a users account with that specific rfid tag. The other software compiled into Arduino Uno, which connects to wifi and the reader stays ready to read a tag. When a tag gets in to the range of reader, Arduino reads the tag and pushes it to server to handle the server-side processes.

So we like this protoype to be wireless and mobile as possible. And we need it to run as perfect as possible in a 1.000 square meter hall room with enough strength/signal. (I say wireless because we really don't want to lay out cables allover 1.000 sq/mt)

  • There is this fact of battery which is drained by WiFly, what is the best way to let Arduino stay alive long enough like 20 hours a day? Datasheet says WiFly features "Ultra-low power - 4uA sleep, 40mA Rx, 210mA Tx (max)" (I will leave it on whole day tomorrow with a 9V battery and see how long it will stay alive. While developing it drained some batteries but I didn't pay attention to power, it wasn't our priority at that time..)

  • I have concerns about the range of the WiFly Shield because of the area factor. I am thinking of creating a laptop / hotspot in the field then connect all the Nodes to this hot spot. Then expand the router range with a couple of access points. There is also "2.4GHz Antenna" for WiFly which I received couple of days ago, I will try to test this on the field too (tomorrow probably.)

I guess this would be all, my biggest question is if this WiFly will have issues to connect to WiFi in the field in strength and signal wise - Of course it depends on the field but there won't be any concrete walls or something instead a lot of cell phones. / or even may be external antenna will be unnecessary?

And battery issue.. I don't know how to calculate how much energy it needs to run 20 hours a days for 10 days or what kind of battery and connection I need. If this gets too expensive and complicated I always have the option use a wall adapter.

Also I was thinking of having a 1" oled screen to each node so we can use it as a serial monitor? is it feasible?

Thank you very much for spending your time and getting interested with me.

No body wanna help me out?

Since you have a working prototype, why not just experiment with it? The WiFly module should do well in your empty (no walls) hangar of 35m x 35m (aprox 1,000 square meters). The battery consumption depends on the software as well. To save the battery, you will need to do http requests (those take 210mA) as rarely as possible.