So I built three little bots so far.
One with a raspberry-pi, (6V motors), one with an arduino (12V motors), and another with an arduino but a hacked remote car (7ish, volt motors):
The problem I have with all these is that the motors spin so fast the car just bumps into something in a few seconds. (I have a small house)
I tried to use PWM to control the speed, but at a little less than full throttle (255) they jam up and they can't take the weight I put on them.
Should I buy one of these chassis that slow the motor down and give it torque with a gearbox, or is there anything else I can do?