cheers!
this is very cute 
welcome to LMR!
Nice recreation
The integration of the IR sensor into the Wall-E head is very nice, good fabrication. I knew who it was right away!
About the 2 different power source
I used 2 different power source to eliminate the noise and power fluctuations generated by the DC motors. One power source for the DC motors, and one for all the electronics and sensors.
And yes I put a lot of effort to make the original articles on the www.hobbielektronika.hu website, because there are no basic level robotic tutorials on the internet in Hungarian.