Driving Module 02

This is a kind of practice work.

Rear Driving module recently created.
Date of creation : August 31, 2009
PF XL motor is used and total gear ratio is 1 : 3.9 overdrive.
Module dimension is as follows :
width = 9
length = 9
height = 8.5(including differential gear underneath)

Gear combinations A->B and C->D both have gear teeth 20->12 resulting in a very fast car.
They can be replaced as 16->16 or 12->20 according to the desired speed of the car.
Differential gear was adopted as seen in the photos.

The last photo shows a test car.
Front(steering) module is also a practice work with clutch gear, but not satisfactory in that
it is so hard to control this car to go straight because it is so fast and it does not have return-to-center mechanism.
These days, I am trying to combine clutch gear with return-to-center mechanism.