Picture of Proximity sensing mouse wheel scroller
List of tools:

1. Exacto
2. Arduino Nano / USB chord (Mini-B)
3. Dremel / Drill
4. Paper & Pencil
5. Sharp IR Sensor (2Y0A21 F)
6. Hot glue gun
7. Solder gun / Solder
8. A small mirror

Ok so you might ask, why the heck are you doing this to a trackball?! aren't those for people from the 80s?? the one with keytars?? My response is two fold. No. 1 I have a keytar and they are MAGICAL. 2. I hated trackballs until I was forced to use one in a recording studio a few years ago, and I will never ever ever ever use a regular mouse again. These suck to get used to, but are amazingly efficient especially from a designer perspective. Not to mention they are very ergonomic. You can hate all you want, I love magical things. But if you do not like magical things, I guess you could just put it somewhere else, maybe the side of a chair? inside a normal mouse (might need a arduino mini for this or attiny)?

Here is a prototype of the sensor, I was trying to figure out where I could put it. You need to pick a good spot where the nano will fit as well as a place that you wont constantly be bumping it, this was the best place I could find. Feel free to move it wherever though. This area happen to have the least amount of electronics too, so it was a no duh spot.

Ignore that its a Arduino Uno in the prototype, I was doing just that-- making sure I could get it to work first. we will be using the Nano or Mini, depending on preference. this tutorial uses the Nano.


Arduino nano is really easy to use if you have never used it. This was my first project using one and I had no problem making the switch from an Uno to the Nano, just a little more soldering.
nerd74731 year ago
great job man
Ugifer2 years ago
This is a great idea!

If you wanted to make it smaller (and cheaper), you should be able to do this with an ATTiny85 - only 8 pins and no crystal required but can be programmed in the Arduino IDE. You would need to run the software serial sketch on the '85 'cos it doesn't have a hardware serial port but I have read that that works and it still leaves you with 2 spare IO pins!

hilukasz (author)  Ugifer2 years ago
I was just thinking about doing this because I want to use my nano for other projects. Maybe I will do this for a version 2.0 :) any links to how to use usb with attiny85? I have never tried this.
Ugifer hilukasz2 years ago
You use a CP2102 based USB to TTL adapter - like this: http://www.ebay.co.uk/itm/251159428933

That sets up your USB as a virtual COM port and you connect the adapter to the software RX & TX of the '85. An '85 is about 50p from mouser and a CP2102 is less than £2 on e-bay. See my "throwduino" instructable for ideas on programing the '85 - you can't program it by serial but you can use the software serial to send & receive data once it's running.

really cool idea! the video seems to be not working though
hilukasz (author)  amandaghassaei2 years ago
hmm I fixed it earlier. it should be working now.