RoboTank #1 / The base

This is the first post about this new project using the TAMIYA Tracked Vehicle Kit as a base for building a robotic tank vehicle.  This will be an ongoing project and you should expect many posts about this subject.  Here's a video where I'm building one of the two kits I got:

Since the kit comes with  a single motor assembly allowing the tank to only go straight forward or backward,  I also bought the Double Gearbox from TAMIYA.  It can be assemble with 4 different ratios: 12.7:1, 38.2:1, 114.7:1 and 344.2:1.  I went for the 114.7:1 ratio since speed is not a necessity.

The tank kit is not build to fit with this particular gearbox so I had to modify the base plate to accommodate the support bar that came with the gearbox but that was meant for another kit.

I want to have an standard Arduino board running as the brain for this project.  Since there will probably be a lot components to control, I needed to drive the motors using only 2 pins from the Arduino board.  So, the next step was to build a motor driver PCB that would accept the inputs from the Arduino and take care of the rest.  This was a perfect excuse to make my first homemade PCB.  I'll get to that in the next post.