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Livestock RFID reader

This is a project that I have been working on for a while. 

A friend of mine has a small farm on a hobby basis and raises sheep. By law every sheep in Norway is required to have an RFID tag in its ear. Though there are several RFID readers out there for reading this type of tags, they are quite expensive and not all that hackable. A reader like the HHR 3000 Pro would cost you about $900,- and to hook it up to an electronic weight would probably set you back another $3000. So for many hobbyist farmers this is not an option.

The base of the system is a FEZ Panda II running NETMF under C#. I could probably be made with something like an Arduino but as I needed to have several UART’s and a SD card to store data, it was much easier to go for the Panda. Also as the Panda has lots of IO pins, hooking up the HD44780 display is done directly with no serial interface and no use of the pins that would go to the Arduino style header. In fact all the pins for the Arduino shield interface are available with the exception of A0 that is used by the weight cell amplifier.

As this might be produced in small quantities I decided to go for a proper PCB. That means that reproducing the device is easy and it looks more professional.

The main box (IP65) holds the FEZ Panda II. On that the main board sits with its headers for the 2x16 LCD display and the weigh cell amplifier. It also have a small coin battery to keep the RTC running.

The RFID reader is mounted on a rod made of 16mm plastic pipe (used for electrical installations in Norway). There are several 3D printed parts on this rod and the handle has a small vibration motor mounted so the user will know when the tag is read. There is also a function on the rod for lamb fetal count, this is based on a PICAXE 18-M2.

The main board also has a Bluetooth interface so the data can be picked up by a PC, PDA or any other Bluetooth device.

One of the main uses for this device is when weighing the sheep. For this we got a 500kg weight cell of eBay and it’s hooked up to an onboard weight cell amplifier that feeds the A0 with data. The weight is constantly calculated and written to the SD card (and Bluetooth) once the RFID tag is read.

All in all a fun project and according to my friend “Weighing the heard is not work anymore. If one only could get the sheep on the weight platform faster”

With the load cell amplifier taken out. You can see the battery for the RTC

With the display taken out


The main board also have a Xbee footprint that can be used instead of the Bluetooth if so desired. The Bluetooth is soldered straight on to the pads SMD style.
There is also an option for a INA125 amplifier instead of the mounted one. A potential next version will probably have an integrated load cell amplifier.


The custom boards that I have had made for this project.

The rod also doubles as a handle for transportation.

Update 02.11.2012

As there has been some interest for this device I put a question out to GHI electronics about the availability of the Panda II. http://www.tinyclr.com/forum/topic?id=7826 and as the response was not a definitive yes I thought I might make my own custom board :-)

The FEZ Panda II sells for $39.95 but the only thing I really need is the microcontroller which cost $16.95. I still had to add my custom board on top of the Panda, so why not try to build a custom board around the USBizi100 Chipset that the Panda II is based on.

The USBizi100 is a 100pin QFP with a pitch of 0.5mm and by far the smallest thing that I have ever soldered. But with lot of flux it turned out very well. I haven't tested the complete system yet but everything seems to be working so fare.

This version has a single board holding the ARM3 microcontroller, Bluetooth, weight cell amplifier and jumpers to put the USB in host mode (for a USB memory stick).

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Hey SauID,

Seeing your build has made me think about doing something similar for my dad.  He is a farmer, and not young any more, and this might be able to be combined with other things to make labour saving devices (automatic gates, etc).  However to do that it would need more range than most of the available RFID cards I've seen (I'm thinking a range of a metre or more).  How much range does the reader have?  The RFID cards I've seen only have a range of a few centimetres, but to be useful to me it would need to be 1 metre.  Can you increase this by adding power and / or an antenna?

Thanks a lot,




This may be in the ballpark of what you are looking for. The specs say 1 to 6 meter range( dependent on a number of things I'm sure). And yes, definately not cheap for a premade board.


My step-father is also a farmer and anything that can be added to his business to make life easier is a great idea. Good work here.

I don’t think this RFID reader will work as most animal RFID tags operates in the LF range (120-150kHz) and not UHF. The tags we are reading is designed for a 134kHz reader that supports the FDX-B protocol.


Yeah.  The ear tags are all in the lower range here as well.  An interesting shop though Jerz - thanks!

The range of our RFID reader is only a couple of centimeters so if you need to read this from further away you probably need a bigger antenna setup. They are quit expensive but if you look around the net you probably find what you are looking for. Best of luck.

Your builds are always just clean and perfect in a manner of speaking. Nice idea to save money by building that ear-ID reader by yourself. 

This is some fantastic work Geir! I`m curious as to how the wand will hold up over time. We repair a commercial version of these available in australia and the wands get treated so badly. Farmers often use them to whack the livestock or chuck them on the ground to chase after the animals.

The goal for this project was to build a cheap and functional RFID reader. So the handle probably won’t take much abuse before it cracks or breaks. But that’s more of a problem for the farmer. If he uses his iPhone to hammer in nails, it probably won’t last as long :-)
As this is a prototype there is still the issue of waterproofing the wand. As you see the lamb counter has the PICAXE in a socket and all the electronics is exposed. The plan is to solder the PICAXE directly onto the final version and coat everything in PlastiDip.
Thanks for your comment ezekiel181

I have to echo the sentiments of my peers here, Geir. This is a marvelous use of your talents. I live in Iowa, which is America's maize and pork nexus, but we have livestock of all kinds (from buffalo to ostrich) on a boutique farming basis for which a product like this would prove, as you've demonstrated, most useful. Have you considered marketing it or open sourcing it? Thanks for sharing. Your virtual comradeship always makes me proud to call myself an LMRian.

I probably won’t start making it. But some neighboring sheep farmers have shown interest for it,  and as the PCB’s comes in batches of 10 I could probably make that many.

There are still things that I would like to explore before this goes beyond my friend. 

  • Building a Windows application to communicate with the unit over Bluetooth / Xbee to give the user full access to files and folders on the SD card. This way the unit could be permanently mounted at the barn where they will be using it.
  • All the data here in Norway is usually uploaded to http://www.animalia.no/English/About-Animalia/ and they are just releasing a webservice that we could hook up to.

But yes, at some point this will probably be released as an open source hardware and software project.
And thank you for your comment Maxhirez