Cool Robot you have. Always nice to have enough parts to build two robots. I,m not that far (yet) ;-) I discovered that you used an Arduino UNO in combination with the Arduino motor shield. Perhaps you can help me out, because I have the same combination attached, but with only 6V going into to the motor shield, the robot barely goes anywhere. I think the problem might be a lack of power. Now according to the Arduino website, you need to cut out the “Vin Connect” jumper if you want to use separate power sources a 9V battery case for the UNO and a 6V battery case for the motor shield is what I had in mind in case it turns out that 9V to the UNO alone isn’t enough improvement. So before cutting off any pins, that I might want to use in the future, I like to know if that’s necessary.