This section covers the actual hardware construction of the robot. The first prototype robot is described. Everything in this area can be modified to do it your own way. Except the basic differential drive motor scheme has to be maintained to be compatible with the microcontroller software. The motors, drive system and encoders do not have to be the same, but must provide the same basic interface. See more details of the motor interface elsewhere.
Leaf is a pretty standard differential steering circular robot. This is done just to make navigation easy and since I already had software for the microcontroller to drive this setup.
Note that it is possible to build Leaf as a dual track robot; however we have found that it takes very strong motors to turn a heavy robot on tracks. Strong motors = heavy robot and bigger batteries.
The robot will be built as modularly as practical. The idea is to make major parts as independent as possible so that major pieces, like the drive system, can be replaced with minimal impact to the rest of the robot (boy, am I an optimist!).
The main modules will be the:
Base: including the platform, the motors and casters
Frame: the body structure that sits on the base
Shelves: To support electronics and other parts
Laptop mount: To hold laptop to front of frame
Power panel: Power control switches and circuit breakers
Head with pan/tilt capability to support webcam(s) and other sensors