GRUNT - General Robotic Navigating Utility Trailer
February 8, 2009
This was an interesting robot posed to me by my mother of all the luddites I know....
I'll spare the forums of the entire details of how this came to be, but let's suffice to say that we have a few equines on ourproperty and barn cleaning is not a pleasurable task.
Appearance - GRUNT will appear to be a tracked assembly on a metal frame (much like a lawn tractor without the body) with a metal, open top box above. One end of the box will be hinged at the front, the door will be able to be open to simulate a dumping cart. In the back will be an upside-down U shaped bar and a manual control panel.
GRUNT's task is rather simple, and possibly a few modes.
Neutral mode = Grunt works just like a lawn cart, no brain and no power.
Manual mode = A joystick or a key pad mounted behind the box that allows the user to guide GRUNT to where it needs to be. A switch or buttons for setting the mode will be needed as well as an easy to reach plunger to stop GRUNT in case of malfunction. Also another button to set waypoints for Automatic mode.
Automatic mode = Follow the preset program and Waypoints (which will be nothing more than plastic or metal discs that can be placed on the ground at various points that contain some small, switchable electronics that allow GRUNT to detect them, move over them and then align to the direction they 'point' and do what they program says.) Program would be a text file on it's system or a preset uploaded program. Directions would be along the lines of:
WAYPOINT LOADPOINT # A directional waypoint (find the point, move over it, turn to be pointed in the same direction)
DO # Basic direction to loop
WAIT FILL # Monitor the box's weight to be within 5 pounds
WAYPOINT 1 # Navigate to Waypoint 1
WAYPOINT n... # Navigate through ALL Waypoints...
WAYPOINT DUMP # Another directional Waypoint (find, move over it, align and dump)
WAYPOINT n... # Navigate back
WAYPOINT LOADPOINT # directional waypoint (you get the picture)
LOOP # go back to the DO and repeat
Again, I'm planning to use Linux and an old motherboard, though power won't be as big of a problem this time with the engine. (low battery = fire up the engine.) Might need to monitor fuel, though. Possibly put a float on an older cap, but take off the gauge and replace with a Potentiometer and read the resistance. Going to need a way to navigate and find the waypoints and maybe do some mapping as well. US sensors look viable to detect collisions.
Now, I'm figuring a different power source for this robot, a gasoline lawn tractor motor, electric start connected to a relay to allow the circuits to start the engine and shut it off to conserve fuel.
The trick will be making a transmission to power tracks instead of wheels, and the PTO to pull the chain to dump the box. OR the harder part will be making a standard drive wheels and steering.
Still working at this one, very early design...