First off, before I get into the details about the robot itself, I would like to explain 
about the boxes I taped together (the stairs).I tried to find boxes that had about the same 
hight which was 8.5cm. I put the robot on the boxes and measured to try and find the right
distance between boxes which was 13.5cm. Then I taped all the boxes together and put a 
support underneath the last box for stability. At the narrowest point it is about 24cm.

Now onto the robot itself.

1. Power
The robot is powered by two battery boxes ; One for each side of the robot. Each battery box
powers one side of the robot which allows for turning at the top.

2. Treads
Four treads help the robot grip the boxes. Each tread has 3 hubs; one to drive, one to secure
the other end of the tread, and one in the middle to help keep the tread from collapsing 
when it is going over a box edge.

3. Balance
On my first version of this robot, I had the notors in the middle. I realized that by 
putting half the motors at the front, I could go up the stairs without the middle of the 
four treads from getting stuck on box corners. In addition to the placement of motors, the
little 4x6 45º bend things help keep the bot from flipping off the stairs or falling off
backwards.

4. Data
Up time    2.91 seconds
turn time  1.20 seconds
down time  1.34 seconds
total time 5.45 seconds