[chbot] Robotic Sweepers

[Marshland Engineering]

> Your little 150cc (assuming 100% volumetric efficiency) is consuming
> 0.18g of air, and having about 8.5g of fuel added to it.
> At 1000rpm its 60mS/cycle but only half that is the intake, so 30mS to
> suck it in.

It's running at 13000 RPM, so that is around 2.5 ms for a charge. If my 
reading is accurate, then the air speed can be up around Mach .7 in the 
manifold.

Vacuum cleaners work around pressure difference, not suction. For a bit to 
be picked up, the pressure difference around the  bit has to be higher than 
gravity's suck. So the higher the air flow into the cleaner the better the 
'suck' which comes back to quite high input power required.