Acrobat Cable Cam
As I've been making instructables, I've had a good time making videos for my projects. This creation gives me a chance to flex my creative license. It's an all angles cable trolley for your camera. It gives a way to film rolling or panning shots from both a bird's eye or worm's eye view. You can use it on a zip line, pull it along, or hold in your hands. It's powered by me or gravity. No servos, gyros, or motors.
I made it to fit all my cameras which are 5" wide and smaller. This includes cameras like the GoPro and iPhone as long as you have a tripod mount.
You can find the CAD file in Step 1. You can also support a project for it on Kickstarter.
https://www.kickstarter.com/projects/699604098/acrobat-cable-cam-an-all-angles-camera-trolley
Prototyping and AutoCAD
The very first prototype was made from aluminum flat bar and screen door wheels. After playing around with it a model in real life I turned to AutoCAD. A few hundred mouse clicks later. I had this design. I like to make paper models before getting it cut. Since it looked good I went to the the laser cutter.
Downloads
Forming the Parts
I added holes to help me form the parts. With two holes at each bend I was able to line them up in my vise by sticking hobby files through them. From there I used a rubber hammer to fold the part over. This kind of aluminum is not very good for 90 degree angles so I would use more of a radius next time around.
Smoothing the Edges
Right off the laser cutter, the parts have a sharp edge. I used my trusty little tumbler to knock the edges down. If you're not familiar with a tumbler it's basically a vibrating container filled with an abrasive. In this case I tumbled the parts over night.
Putting It All Together
After all the angles were formed in I picked up a whole bunch of hardware. It's all labeled in the first image. My original wheels weren't precision made by any means. That was a problem because it caused a lot of vibration in the filming. I upgraded to a larger better made wheel and that helped a lot.
String It Up
I found that if you put too much tension in the line it acts like a violin string. With a little wind it vibrates and actually puts out a pitch. I had a good time with it. People who saw it in passing also thought it was fun. Thanks for reading.