How to Make Desktop Vacuum Cleaner Robot

Not long a ago, I started to search Instructables to find how to build a obstacle avoiding robot, then I had this idea to build a mini version Irobot vacuum cleaner. The development process takes about 3-4 months since i had to figure out how hardware/software and mechanical works, I build the model in pro-e and printed out with a 3D printer. The device is powered by 5v from any PC's USB port with a USB cable, I use Atmel328IC  and coded it with aduino development software. .
Follows the pics' order.
1) Design sketches.
2) Schematic (hardware)
3) Pro-E modelling
4) 3D printer printout
5) Prototype on hardware
6) Software coding and finished product
Here is the result of vacumming demonstration 
http://www.youtube.com/watch?v=SSIhU_ySWnc&feature=youtu.be
Vacumm at work
http://www.youtube.com/watch?v=E72U4YS4Qv8&feature=youtu.be
More introduction to the vacuum cleaner. 
http://m.youtube.com/watch?v=i4OU7kBHwws