Robot Project :: Robot Completed

My first robot project is now completed. It only took a weekend afternoon to complete, but I let it lapse while focusing on my dissertation and research this fall.

The function of the robot is simple: detect light to the left and right and continually drive itself while remaining within an area having light.

I've been able to keep a low budget by finding materials for free or creating parts from what would otherwise by trash. Here's a short list of the components:
- Body: 1/4" thk. PP sheet cut to the size of a compact disc.
- Sensor body: electrical tape.
- Wheels: peanut butter jar caps and rubber bands.
- Attachment: screws (wheels) and velcro (nearly everywhere else).
- Rear stabilizer: Tenergy 2000 mAh 6V battery.

Some of the key tricks/modifications necessary:
- The Hitech HS-311 servos are made stock to only rotate 90 or 180 degrees. The servos must be disassembled and modified to permit 360 rotation; they also must be calibrated to prevent rotation when not desired.
- There were no complete instructions for creating the programmer circuit on the board for the Pololu AVR programmer. Another hobbyist provided some direction with this.
- The C-code needs to be tuned to improve the response to sensed ambient light.

Final verdict: the robot rotates the wheels to move in the correct direction when one sensor is exposed to light and the other is blinded. However, the response to areas of light and shadow in the floor of my apartment are less than the accuracy it needs to work well. This may be due to the shine off my floor or poor lighting. I'll post a video once I find a surface and lighting conditions where it works well.