Follow my finger!

24th August, 2013

Mentor – Dr. Sunil Kumar Singla

This project was my first adventure into the field embedded applications development. I approached this project as an electronics engineering student looking to apply my knowledge of micro-controllers, sensors and actuators into building something new and interesting (my prime intention since a long time). This work made me experience the joy of seeing that LED finally glow (when something works as expected after numerous, long sessions of rigorous debugging and the concerned LED glows).  In this sense, this project was special. Further, I thoroughly enjoyed “playing” with this simple finger – follower that I had created (considering that I am obsessed with movement and the intuitiveness related to movement/ gesture based control of things). Lets look at the implementation.

You can view a running video of the system here.

Technically, this project was relatively simple. I used a Parallax TSL1401-DB linear (one dimensional) sensor based camera module to sense the position of the finger. The line scan camera was interfaced to the MPC5604B micro-controller via a custom communication protocol. The software running on the controller initialized the camera module and enabled the finger detection functionality. Ultimately the angular position of a DC servo motor was controlled in accordance with the moving finger thus justifying the “finger – follower” metaphor. An accurate and responsive (minimum lag) proportional-integral-derivative control algorithm ensured that the motor followed the finger well and the whole thing looked (and felt) natural and intuitive.

 

FullSizeRender (5)
The “finger – follower” setup