Created and maintained by Bill Beaty. Mail me at:
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AN ANTIGRAVITY CHAMBER
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TV camera on a board . |
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Cardboard Box
CONSTRUCTIONCut the cardboard box so that one side is missing, which gives a good
view
into the long narrow box. Attach the board to the side of the box, and
attach the camera to the board. The camera lens should face into the box.
(For convienence, build this with duct tape at first, use screws and bolts
later on.) Affix a small flood light adjacent to the camera, and aim it
into the box so that the camera has enough light to "see."
Connect power to the camera and flood light, and connect the camera to the
TV or video monitor so that your audience can see into the box. Adjust
the camera's zoom and focus to give the proper view of the interior (you
may have to use the camera's "macro" mode.) For best depth of focus, make
sure the interior of the box is brightly lit, then adjust the camera's
f-stop for a high number.
OPERATIONPlace some objects inside the box. I just grabbed a spool of tape, some magic marker caps, and a bottle of white-out, and dropped them in there. Watch the image on the TV screen, and carefully rotate the entire box assembly until it is upside-down. Your audience will probably break out in laughter, because the image of the box on the TV monitor will remain still, but the objects in the box will crawl up the wall and roll around on the ceiling! Violently shake the box, and the objects will seem to be flung about invisible forces.
To generate free-fall, suddenly lift/jerk the box so that the objects are
launched off the "floor" of the box, then try to move the box to follow
the objects so they momentarily stay centered in the middle of the box.
Don't let the box go, or you might damage your camera! Your audience will
see genuine ( and very brief ) free fall effects. The objects will leap
into the air, then will drift around spinning, then will suddenly fall
hard onto the floor.
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FANCY VERSIONIf you have some ambition, you might wish to decorate the inside of your box. Paint it and add extra shapes to convert it into the inside of a space station. Add some small human figures (Barbie, etc.) dressed appropriately. Or, maybe decorate the interior so it looks like the padded cylindrical interior of NASA's "vomit comet" free-fall airplane. Dress your action figures in orange jumpsuits, and provide some air-sickness bags for the Senator!
If you have a sick sense of humor, build the inside of a commercial
airliner into your box. Add passengers and steward/stewardesses, luggage
racks, etc., then simulate what would happen if the 747 pilots decided to
do loop-the-loops! Fear of flying? Or, you can fill your box with
doll-house furniture, then show what a moving van looks like as it bounces
and rolls down a steep hill. An "adventure in moving!"
This box/camera device duplicates the workings of NASA's free-fall
simulator plane. Rather than climbing into a full sized aircraft, we use
the video camera to shrink ourselves down and take a Virtual Reality ride
inside the box. To generate free fall, the NASA plane flys in a
parabola-shaped trajectory. Why? Well, imagine what would happen if the
crew was inside of a box which was shot out of a huge cannon. Both the
people and the box would fly along similar paths. The box would take a
long, curved, up and down path, and so would the people inside. The people
inside could not see the box move, so they couldn't know they were
falling, instead would think that they were weightless (at least until the
box struck the ground.) So, if an airplane flys in exactly the same path
as a fired cannonball, everyone in the plane will seem to be floating.
NASA free-fall aircraft: http://www.nasa.gov/missions/research/kc135.html
SIMPLE NON-VIDEO VERSIONIf you obtain a small box, a shoe box or large cereal box, open up one end, and stick your face in, you will have the "poor man's version" of the video camera box. Stick some small toys or coins into the box. To generate momentary free fall, simply jump up and down. The objects inside the box will float for a moment. ( Be aware that jumping up and down with a box on your face looks really stupid. This demo is a great excuse to convince OTHER people to jump around with boxes on their faces, while you stand back and watch the fun!)
WARNINGOf course, always try to protect your camera. If you never let the box out of your control, then you'll only have yourself to blame for any mishap. Perhaps it would be wise to attach a hook to the ceiling, and attach the camera box to a rope to prevent accidental contact with the floor. A suggestion: use the tiny $80 video cameras sold by Herbach and Rademan, or by Marlin P. Jones. These things are a couple inches square, and can take lots more punishment than a camcorder. And if you drop it and break it, it was an $80 camera, not a $1200 camcorder. |
NASA student competition: "Drop Tower: http://microgravity.grc.nasa.gov/DIME.html NASA Free-fall Activities http://microgravity.grc.nasa.gov/new/frame4.html NASA Free-fall Education Page http://microgravity.grc.nasa.gov/new/frame1.html NASA Drop-tower Demonstrator http://microgravity.grc.nasa.gov/mini/minit.htm NASA ask a Scientist http://microgravity.grc.nasa.gov/new/frame12.html NASA Microgravity Science Division http://microgravity.grc.nasa.gov/ Gravity Misconception: Gravity in space is NOT zero
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