Public Lab Research note

"Judo Rig" for aerial photography

by tonyc | December 17, 2015 00:15 17 Dec 00:15 | #12524 | #12524

What I want to do

Not break my camera when it crashes to earth, especially on a rough landing from a kite mission.

My attempt and results

I've been playing with a couple variations on rigs, as part of designing a pendulum rig kit for the store.

After toying with the soda bottle rig, I wanted to try to make a simple rig that created a postive mechanical lock to the camera, using the tripod mount, but still had the give of rubber bands to protect on impact.

I came up with this basic idea:


Then I had the brainstorm of using stick legs, but asymetrically to allow the camera to "roll" and transfer energy to horizontal motion. So I stuck the dowel legs in, and played around with rigging until it also was tied in to the main suspension to give more rubber resistance and give. (that makes no sense, I know, but you'll see in a second...)



And that's it. The legs spring a bit, the camera slides down a bit, but not enough to cause impact, and the sticks transfer force back to the rubber bands at the top of the sticks. Then the whole thing rolls back and onto its little "butt" piece before rolling over.


This was a free-fall test from ~5':

Questions and next steps

Feedback please! @cfastie @pcoyle @mathew

Why I'm interested

Want to have a good model to demo before shipping the pendulum kits.

I did this Help out by offering feedback!

People who did this (0)

None yet. Be the first to post one!


That's an awesome crash test. I think taking advantage of the tripod socket is a really good idea. The little tripod head you use is more than you need, but it should work well (all you need is a plate with a hole or a coat hanger wire with a loop). The leg system looks pretty effective. I would immediately add two more legs. Kites can drop and let the camera hit the ground, but more often a much safer landing can involve the camera being dragged over the ground. You can't predict which way the camera will be dragged, or even whether it will land hard at an odd angle. I have never flown a camera with so little protection, but many people do. It's probably a good idea to give beginners an easy way to surround the camera with protection.


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Tony, I looked at the note in email before I saw the comments from Chris. I like the innovative thinking. The drop test is cool

I'd second the point on using 4 legs, or camera enclosure, for the reasons Chris noted. I recall some years back Brooks Leffler of, commented on our protective measures for cameras, something like "... just learn to fly so don't crash..." Some of the KAP crowd fly cameras with little or no protection.

As alternative to the wooden legs, if wanted to surround camera with protection, looks like a juice bottle enclosure (opened up at the top) could be added to the basic idea with a hole or slot to accommodate the tripod socket screw.

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I like Pat's idea of bolting through a juice bottle.


Removing the neck of the bottle could allow good access to the camera, but the bottle shoulders would provide strength. The plate might have to be bent to keep the camera level. The plate should be pretty easy to make out of cheap aluminum. Tough plastic would also work but the shaft attachments would have to be different, and bending it would be an obstacle.

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McMaster Carr sells aluminum strips 1/16" thick in widths between 1 1/2" and 2" (in various lengths). So a one foot long piece would cost less than $2.00:


I'm not sure that material would be strong enough for this design, but something similar should work well. This rig could also be suspended from a Picavet.

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Awesome ideas, y'all! Mainly I was trying to get the protection centered on the lens, and to get the thing to roll, not resist with rigid protection. That was the thought experiment. And the other assumption was that if it was oriented (hung off a pendulum so the "butt" piece faced the operator, then when the rig was coming in for a landing, the operator could prevent a "header" by yanking on the string, so the rig would slide on the legs like a travois, or worst case, land as shown, with the legs protecting the lens.

Anyway, lots of cool ideas here. Thanks!

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