I ordered this motor:
uxcell DC 12V 7RPM 50Kg.cm Self-Locking Worm Gear Motor with Encoder and Cable, High Torque Speed Reduction Motor
I have an Arduino Uno and a 12 Volt battery supply from 8 AA batteries from my previous project.
I found a few tutorials:
Tutorial for DC Gear Motor With Encoder
Tutorial for Monster Motor Shield VNH2SP30
This new motor is slower but has more torque than the motors I used in my last attempt at an autonomous robot.
The older motors had
Torque: 30 N*cm
According to Wolfram Alpha that’s:
3.059 kgf cm kilogram-force centimeters.
This new motor has 50Kg.cm.
I ordered a few items on Ebay: