I finally built asuro:
It already can move around on its own and if a key gets pressed of the front sensors, it moves backwards and changes its direction. Now my girl and me want to put a floor cloth under it and let it move around the house .
With asuros creation, I also got the data sheets to build a very easy H-bridge driver to control little DC engines. Now I can use that for several purposes, most important purpose to sell it and make some $$. For that I thought about to build some box of plastic for it. So I learned a new method that enables you to thermoform plastic in your basement:
You take an isolated wodden box. Then you drill small holes in the top. Then you drill a big hole in the side that does exactly fit a vacuum cleaner tube. Then you need to carve a so called photo negative shape from wood, you'll use to shape your plastic with. Then you need to aqcuire a plate of easy bendable plastic, lay it on top of your carved form and that you lay on top of the box where the small holes are.
And now you're set: you put the whole thing in an oven, heat it up and when its starting to melt you switch on the vaccum cleaner, inserted in the big hole on the side and the thing creates a vaccuum that pulls the melting plastic thru the small holes in the top piece of the box .
Here's a picture of a box build by a profi ( on the left with the metal plating on the top ):
Here's another one doing it even without an oven: