Gravedigger by Matt Meerian

Gravedigger was design to compete in a timed competition during 
Open House festivities at Kansas State University in April of 1996.
The competition was laid out onto eight sequential sheets of 
4' x 8' plywood.  There was a gate between each section of the 
competition so the robot would know to run the next program.  
Gravedigger had the best time of any entry into the competition.  
There were about 16 robots entered

Line Following:  We had two photo-transisters looking down near the 
front of the robot.  Their job was to determine if the area beneath
them was light or dark.   

Maze:  Since the maze was made out of 90 degree angles, gravedigger
simply went into the maze, detected a wall, aligned against the wall,
turned right, went forward, detected another wall, turned left, 
went forward, detected another wall, turned left, went forward, 
detected a wall, aligned against the wall, turned right, and was 
out of the maze.  Gravedigger entered the maze going forward and
exited the maze going backwards.  The reason for exiting the 
maze backwards was so Gravedigger could pick up the golf ball 
on the next sheet of plywood. 

Half-Pipe:  Gravedigger went into the half-pipe competition a 
certain distance to pick up the golf ball.  Next, Gravedigger 
would turn to go up the half pipe.  It would usually make up 
to the fourth mark.  The higher the golfball went, the more time
bonus the robot received. 

Beacon Chase:  The modulated infrared beacons were over paddles
that turned the beacon off.  Gravedigger would go to the center
of the plywood, circle around looking for IR beacon, find it, 
and precede towards it until it was off.  It would then go back 
to the center of the plywood and repeat the sequence three more 
times. 

Bridge and Tunnel:  The hardest part of this section of the 
competition was navigating across the bridge.  Since there was 
nothing to keep the robot from falling off of the bridge we 
designed a clever strategy to accomplish our goal.  When we made 
it to the start of the bridge, Gravedigger went strait ahead for 
90 ticks, turned left, went strait for 120 ticks, turned right, 
went strait, met a wall, turned right, and then Gravedigger was 
set to go down off the bridge and through the tunnel.  Interesting 
note:  when Gravedigger topped the incline going backwards, his 
front end would lift up and release the golf ball from the Half-Pipe 
section.  The golf ball would then roll down the incline. 

Blind-folded football: Gravedigger would go into the last section, get a 
fix on IR beacon over the exit, and head towards it for 3 seconds.
After these three seconds, it had plowed through the two guard 
robots and was set to get another fix on the exit.  Fortunately, 
Gravedigger was much larger than the guard robots.  The only problem
we ran into was Gravedigger couldn't see IR beacon when it was 
right underneath the exit.  Something that helped was to back up
a little and look for the IR beacon again. 

Many thanks to Mike Novak for the great programing job. 


Email: mmeerian@ik.pathnet.net