Updates:

Started the build by getting the base and making the axe mechanism:
IMG_3460.JPGIMG_3459.JPGIMG_3462.JPGIMG_3468.JPG

Right now it weights 8,5kg including the axe, the gear ratio for it is 5:1, having on the handle 55 teeth and on the motor 11.
The base is 2,5mm steel and the dimentions are 315mm X 370mm not counting the slots for the wheels.

This is what (hopefully) it's going to look:
Cattura.PNG

I decided to make a lower body (kind of looks like K2 now), to save weight, and the scooter motor is closer to the center:
Cattura2.PNG

I will think of a cover for it later.