Recently I got a chance to play around with a “Makey Makey“. If you have never heard of a Makey Makey it is an invention kit that tricks your computer into thinking that almost anything is a keyboard. This allows you to hook up all kinds of fun things as an input. After a few hours of attaching gator clips to everything on my desk, I started to see the potential of using this type of device with LabVIEW, you would be able to quickly create a physical interface for a VI. I decided to try and recreate the functionality of the Makey Makey using a WF32 and LabVIEW.
The picture below from the Sparkfun website shows the simple top side of the Makey Makey. When you flip the board over, you’ve got access to 12 more keys: W, A, S, D, F, and G on the keyboard side, and up/down/left/right mouse movement and left/right clicks on the mouse side.
I used a breadboard and the analog inputs of the WF32 to recreate the functionality of the Makey Makey. This allows you to turn 12 everyday objects into touchpads.
This circuit works as a voltage divider (simple drawing shown at the bottom of the picture above), with one of the resistors (R1) being the 2 1MΩ resistors in series and the second resistor (R2) is the resistance of your body. The switch shown above is closed when you complete the circuit. Let’s say you hooked the gator clip to a banana when you touch the banana you are closing the switch and lowering the voltage read by the analog in of the WF32 (Vo).
My LabVIEW VI allows you to assign specific keyboard and mouse commands to each analog input.
Below you can see the full list of all possible keyboard and mouse options that you can assign.
Thank you for reading my blog post, and make sure to check out my Instructable where I give detailed step by step instructions for this project. If you are interested in making this yourself but don’t have the right supplies you can purchase the LabVIEW physical computing kit with chipKIT WF32. This kit includes a copy of LabVIEW 2014 home edition, a WF32, and everything you will need to run LINX 3.0 and start making projects. Also make sure to check out the Makey Makey, which is sure to provide hours of entertainment. Please comment with any questions or comments you may have.