FlyStand - How I built a camera stabilizing system
I've always been fascinated about movie making, all the props and gadgets used, lighting, cameras, special effects and such. One thing in particular is the SteadicamTM. A device which stabilizes the camera and prevents shaking and bouncing, and can - with a good operator - make the camera "fly" through the scene.
Background
When my wife and me bought a miniDV camera (a SONY DCR-TRV18) I begun wondering
if it would be possible to use a Steadicam system with our cam. I begun checking
on the Internet for information. I quickly realized that buying a real Steadicam
system was out of the question. However, I learned from the
Steadicam FAQ
by Eric Swanson how it works and I have based this idea on the same principles,
although this is a quite simplified version.
VARIOUS FORCES
How it works
A camera is exposed to a number of different forces while operated. If the camera
is pointing in the black arrow's direction, then you have the panning (red),
tilting (green), rolling (blue) and gravity (purple) force, besides being moved
around (forward, backward, left and right). The stabilizing systems works by:
1. Isolating the operator from the cam
2. Spreading the cam's mass to create a higher resistance to rotation, and
3. Moving the cam's center of gravitation outside the cam
My design focus on point 2 and 3 only.
CAMERA FRONT
When you hold a usual camcorder with your hand, the camera has its mass and center of gravity focused to a point inside the cam. This means that when you are moving it, you are actually turning it by its perimeter, where it doesn't take much force to rock the cam and get a shaky picture. It's like spinning a record on a turntable by pushing it by its edge. It's fairly easy.
CAMERA ON POST
What the Steadicam system do, is to shift the cam's center of gravity outside the cam (3) by putting it on top of a balanced vertical post. To keep the post in perfect balance, it has a counterweight at the bottom, normally consisting of a monitor, batteries and such. We've now spread the cam's mass over the entire post and by that increased the resistance to rotation (2) since there is now more mass to rotate (mainly tilt & roll).
With a Steadicam system, the post is then connected at its center of gravity, by a gimbal, to an "articulated arm", designed to absorb vertical movements (1). The arm is attached to a vest that the camera operator is wearing. My design doesn't have a gimbal or articulated arm, nor any vest. I'm gonna use my own hand and arm to hold the post. By handling the post at or near its center of gravity, you are now actually trying to spin the record by turning the center spindle of the turntable instead of the record's edge. This takes a lot more energy and by that we've eliminated some shakiness. On the other hand, the cam now weights more, but... you gain some, you loose some. In a Steadicam system the articulated arm compensates for this extra weight.While browsing around the Internet I came across some similar, simplified designs of the Steadicam, such as the GlideCam 2000 Pro. I also found a reseller in Sweden (where I live) but they charge about SEK 3500 for it and I thought it was way too much. I also saw another site where they sold drawings and instructions for how to build your own stabilizing system and that's when I realized that I should be able to build my own. So, I decided to make my own design from scratch.