Re: Trash-Bot

[Phil Hobbs <pcdh@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>]

Bill Kearney wrote:

> You could hack the brains out of one of those robotic lawn mowers.  I don't
> recall them needing buried wire.  Likewise a radar sensor could deal with
> unexpected obstructions.  Even machine vision would work. Since it's
> following a regular track it'd be simple comparison against a known-clear
> path, not actual pattern recognition.
>
> Dealing with someone stealing it isn't technological, but some sort of "I'm
> too far from my base station, scream like a banshee" feature might be
> entertaining.  Heh, have it scream "help, help, I've been stolen from..."
> and start frantically running it's drive wheels.
>
> Hmmm, if they're cheap enough one of those robo-mowers might indeed be a
> cool starting point.  Teach it to traverse a fake lawn path and then hack it
> onto something with enough drive motor horsepower to move the weight.
>
> You could start the experiment by building the cart and using a radio
> controlled car circuit to operate it manually.  Prove that the drive
> hardware works and then cobble up the brain for doing it automagically.
> Hmm, an R/C car design using a gas motor and some sort of battery operated
> starter would probably get around the rather hefty battery requirements that
> moving several cans of trash might require.
>
> -Bill Kearney
>

  C'mon, guys, all this stuff is _way_ too complicated.  It's not the
_robot_ you need to place accurately, it's the _trash_.  I recommend
using Kevlar-reinforced bags, an extra-heavy-duty trash can, a bit of
silicon carbide and water, and a spark plug--ta-daa! the Trash Cannon.
Measure the weight of the trash bag, and adjust the amount of carbide
with a PIC controlling a small motorized hopper.  The metering curve
would have to be calibrated experimentally.

Alternatively, if local laws or jumpy neighbours render pyrotechnics
inappropriate, you could use a Trash Trebuchet.  This would have the
advantage of a much more predictable trajectory, since the initial
velocity of the payload is more nearly constant than with a gun.

Either of these would solve the navigation problem, since the relative
positions of trash can and curb can be calibrated in advance, and both
would be a bit big and nasty to steal.  (Control algorithm suggestions
welcomed.)  A small CO2 laser (eye-safe!) could be used to shoo
pedestrians out of the line of fire.

Cheers,

Phil Hobbs