Similar to a reel mower, except have the blades driven with a real small
torque, say by a loose belt. The blades would turn slowly, unlike a
powered reel mower, and the cutting bed at the bottom could vibrate. The
vibrating motion would cut the grass against the inertia of the reel.
Since the reel scissors the grass across the bed at a small angle, baby
fingers wouldn't be able to reach the nip point before backdriving the
weakly propelled top blade. With the the right vibration profile, you
might even be able to make the motion drive large stuff like fingers OUT
of the nip area, only cutting stuff small enough to get down into the
cutting part of the angle.
Problem: Cannot handle pinecones and sticks. Perhaps a sensor could tell
when the blade was being backdriven or was slipping, and then have the
blade spin backwards to eject the object. Or little arms out front which
pick up pine cones and sticks and throw them out to the side. :-)
-mike
* Michael L. Ross/C33 | Lockheed Engineering & Sciences Co.****
* Robotics Department | 2400 Nasa Rd. 1, Houston, TX 77058*****
*(713)333-7094 voice,(713)333-6071 fax*#include <disclaimer.h>*
* Finger me for my public key. mross nospam at outland.jsc.nasa.gov ****
* If you weren't a socialist in your twenties, you had no heart.
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