This little robot is based off David Hrbaty's great little Ardubot (http://www.thingiverse.com/thing:603907 and https://github.com/davidhrbaty/ArduBot). This is in turn based off the MiniSkybot Robot V1.0 (http://www.thingiverse.com/thing:7989), so the bulk off the assembly instructions can be found there.

I found the little battery pack wasn't providing the power I needed, so I modified the design by getting rid of the speaker at the top and replacing it with a box that contained the electronics, lipo battery and a power switch.

Here is a quick video of it in autonomous mode: https://www.youtube.com/watch?v=0UoXiueChEg

Materials

• 1x Arduino Nano rev. 3
• 1x Ultrasonic sensor HC-SR04
• 2x Servo motor Futaba S3003 modified for continuous rotation (see https://www.youtube.com/watch?v=SK8mhnEzcvY). I would suggest either super gluing the potentiometer in place after you have zero'd it or using the resistor approach.
• 1x Micro servo motor Towerpro SG90 (available on ebay)
• 1x IR receiver TSOP382 or another (available on ebay)
• 1x 7.4v small lipo pack or you can use the 4xAAA battery pack in the original design and place that under the bot.
• 8x 3x2mm (3mm diameter) rare earth magnets (find them on ebay in packs of 50 or 100 - they're quite cheap)
• M3 Nuts - I can't recall how many but 40 should be plenty.
• M3 Screws - A few shortish screws are required. I think I used mostly 10mm and 16mm long screws but various lengths will do as there is space for longer screws.
• 2x 50mm ID x 3.5mm O-Rings for the large wheels. The thickness of the O-ring can be different or you could try and substitute this with something like a rubber band if that will work. (sourced from ebay).
• 1x 13mm ID x 4mm O-Rings. Again like the large wheels, the small back wheel could use a smaller thickness or some substitute. (sourced from ebay)
• On/Off Rocker Switch (5mm wide) - This is optional and you can choose to print the top electronics box with or without a hole for this. I sourced these from ebay.
• Heat shrink to cover the exposed soldered wires

See the instructions for some more details.