Let's Make Robots!

gnd problem

windscreen wiper motor problem


I am building a tank style robot which uses two windsreen wipers (one to run each track).

My problem is that when i try to put both motors running in the same direction( i.e one positively biased and the other negatively biased as they are faced in the opposite directions) the battery is shorted as the housings of these motors are grounded.

Those anyone know of a solution to this problem? or is there another kind of  windscreen wiper motor that does not have the housing gounded?