Frequently Asked Questions - DIY EDTracker

FAQs - DIY EDTracker

Questions related to the home-build DIY version of EDTracker

All the hardware requirements are in the hardware article.

The basic three components (the Arduino Micro, MPU6050 development board and tactile switch) can be sourced for between £5 and £10 (GBP) at time of writing. Coupled with some breadboard and jumper wires, the whole device can be constructed for less than £10 with careful selection.

Hobby Components within the UK provide a simple bundle that provides the bare basics; you just need a soldering iron, some solder and spare wire to complete.

Fabricating your own PCB (or purchasing ours) will increase the cost slightly. We sell the daughterboards for £5 (GBP) for those wanting to do away with the breadboard approach, but if you have the time to etch your own you can download the board plans off the website underneath the downloads link.

Yes, you can, there are development breakout boards that are directly pin compatible and the MPU-9150 is essentially a 6050 with a magnetometer integrated onto the chip die. We have a version of the software that makes use of the magnetometer to eliminate gyroscope drift over long periods of time.

No, not at all. The EDTracker can be constructed entirely on breadboard or stripboard if you wish. Obviously the resulting device will be larger and less elegant strapped onto your head, but it will work nontheless!

Yes! We've had a batch of EDTracker boards made to ease the process - you can take one of these boards and solder the three basic components into them, and you've got yourself an EDTracker device - all you need to then do is program it.

Yes, it is distributed via GitHub together with the source code.

From a functional perspective, not quite but almost. Commercial head tracking products that use infra-red point models and a camera upon your monitor can ascertain the absolute position of your head in space - so not just how you rotate your head but also if you move it forwards, backwards or sidewards. This is called six degrees of freedom (6DOF).

The EDTracker provides 3DOF, but at a vastly reduced cost. 3DOF models only the yaw, pitch and roll of your head, but not the position of it in space (ie. moving is left, right, up, down, forwards or backwards in a sliding motion). Since most games don't really benefit from this, we consider it a good compromise. The main feature of use to a pilot in a simulator-style game is the ability to look around him.

To use it as a virtual joystick, you don't technically need any drivers, however if you want to shut windows up from reminding you (or if you want to program the Arduino microcontroller) you can install the Arduino drivers.

  • Download the latest IDE from http://arduino.cc/en/Main/Software - download the ZIP version rather than the installer.
  • Unpack the zip; you will notice a 'drivers' subfolder.
  • Point your Windows driver search to this folder, and presto - the device will now be recognised.

If your Arduino development board is not a genuine Arduino Micro (or compatible) then you will need to seek advice for your manufacturer/supplier on where to get drivers from.

The board design and code has been tested using an Arduino clone commonly referred to as the "Pro Micro". It is not an official Arduino design, but was developed by SparkFun - it is basically a compact Arduino Leonardo with a few pins (11, 12, 13, A4, A5) missing. It is based on the Atmel ATMega32u4 USB-enabled microcontroller. Since it is a Leonardo clone, it uses the same (Caterina) bootloader.

To all intents and purposes, you should be able to treat it like an Arduino Leonardo (with the exception of any use of the missing pins - but obviously EDTracker doesn't make use of them)

"Mini" and "Nano" versions are NOT suitable as they use the ATmega328P microcontroller and a separate FTDI USB chipset. Check the data sheet for the device you are considering. If it says ATmega328P or FTDI USB, then it will not work.

If you want to use our PCB, then you specifically need the 24-pin SparkFun Pro Micro. If you're building it into your own PCB solution, then you can choose anything that meets the criteria above.

All our firmwares are for 16MHz but you can use an 8MHz (3.3v) Pro Micro if you really wish - but you will need to compile the firmware yourself from source code, modifying a few variables to make it 8MHz-compatible. Given the proliferation of the 16MHz version we'd suggest you stick with it instead; it's easier and obviously better performing.

I'm sorry, but we're not providing these. We had to invest our own money in getting a batch fabricated and so we do not want to put ourselves at financial risk by releasing the design for others to duplicate with little effort. The design isn't complex so anyone capable of fabricating their own PCB should be able to work it out for themselves and make their own, if they really wish.

Ideally the MPU board should be flat on top of the device, with the MPU chip facing upwards. There is currently no setting in the software to mount it upside-down so if you need to do this, you will need to modify and build the firmware from source. Easiest thing is to avoid mounting the MPU upside down if you can.

Yes, with some caveats/notes :

  • You will need to load the specific MPU-9250 firmware
  • Some of the 3rd party 9250 breakout boards are larger than previous, and may require modification of the PCBs and/or enclosures in order to fit (see this article for details)