6.270 Snakes on a Plane (R2) README
===================================

Team 20
Amy J Wooten
Linda Ye
IAP 2006


Technical Things
================

Using OSv.0.1.04, because we failed to see the new v05 before 
impounding. However, we added the kill() function to ensure
that the robot stops before the minute is up.

The source file is umain.c, located in this directory. We have
also included our entire project source (project located in
src/gyrotest).


Brief Code Overview
===================

Most of the utility functions (calibration, turning, driving) are
taken directly from Gyrotest. In fact, we just modified the Gyrotest
project for our robot. 

Color calibration happens during the setup period. All sensors are 
placed over black, then over white, and a cutoff is determined. Once
started, the robot orients itself by determining which square is the
odd one out (or if all 3 sensors see the same color). The robot will
turn towards the ball set closest to it, never more than 90 degrees 
in either direction. Actually, we found that "70" degrees is more 
desirable (for some reason the gyroscope readings don't update as
much while spinning). 

If the robot is faced towards the 4 balls, it will simply push them
into the corner goal and back up. Ideally, it should return to where
it started, turn, and go for the 2 balls. However, we found that
going backwards was impossible due to an inefficiency in our motor
gears or something. Therefore, we simply set it to travel back 
without regard to the gyroscope (using the gyro actually decreases
our chances of going straight).

If it is faced towards the 2 balls, it will try to sense the middle
line, turn 90 degrees, and deposit the 2 balls into the middle goal.
Once it does so, it backs up, turns towards the 4 balls, and tries 
to score in that goal as well. Most of the time, however, the black
middle line does not trip both back sensors at once, so we simply
just push the 2 balls into the corner goal.