Three Axis Gimals - A New Design

P

Paul F

Veteran
It occurred to me that 3 axis gimbals for camera operators are damping the wrong axis. They dampen movement in the pitch, yaw, and roll axis, but don't do anything for the Z-axis(up/down). Well, some have spring arms now, but I'm skeptical about those.

A stabilizer dampens z-axis movement with the arms and controls roll with the bottom heavy pole. The stabilizer does not dampen yaw (pan). The stabilizer controls the axis that really need control. The pan is not dampened and is controlled by the operator for precise framing.

So the gimbal does two things wrong - it dampens pan, which doesn't need dampening or at least severely impedes proper panning; and it does not dampen the z-axis, which does need dampening. I'd like to see a gimbal that has no pan axis and replaces the pan dampening with active (not springs) z-axis damper. This way, the operator would have precise control over the pan part of framing and would remove more of the z-axis issues. Of course, there would now be lag in the z-axis control, but I'd prefer that as it would stabilize the image much better.

The reason gimbals are this way is only because they started out on helicopters, which needed pitch,yaw, roll dampening. But the adaptation of that gimbal to a camera operator is not as good as it could be.
 
Think about how much you need to move to dampen any sizable Z axis disturbance and how big the entire rig will be and how fast it will need to move. The best way to dampen this is through a harness and arm system which has been in use for almost 40 years (I might be wrong and it might be longer than 40 years). The only active Z axis stuff I know of is on vehicles that have been made into camera supports and cost unknown thousands of dollars.
 
Jump to the 5:14 mark (or use this link: https://youtu.be/DRPko1Pts3c?t=314)


Seems like he can take a little of the Z axis bounce out holding it the way he does (tilting the rig 45 degrees), especially when running, where the up down path is much more of a pronounced parabolic arc than a straight up/down.

arc.JPG

(Here's the article that image is from: http://www.real-world-physics-problems.com/physics-of-running.html)

You're definitely on to something regarding the wrong 3rd axis in terms of priority, although I'd probably like to keeping yaw motor and just add an active Z axis.
 
Greg_E said:
Think about how much you need to move to dampen any sizable Z axis disturbance and how big the entire rig will be and how fast it will need to move. The best way to dampen this is through a harness and arm system which has been in use for almost 40 years (I might be wrong and it might be longer than 40 years). The only active Z axis stuff I know of is on vehicles that have been made into camera supports and cost unknown thousands of dollars.
Click to expand...

Yes, active z-axis damping is a bugger because it requires a lot of power, which of course, would defeat the advantages of the small gimbals. The motor and battery required to do it would make it too big. A counter-balance that would allow for smaller motors would also defeat a small/light design.

Yep, the stabilizer is a wonderful thing. The appeal of the gimbal is it size. Oh well, everything is a compromise.
 
I think to be able to do this, you would want a compressed air piston or hydraulic piston to handle the Z axis shift. But I think you still need to limit the Z axis to a small amount of motion or it will get huge fast. Maybe the answer is to use a vest and arm, but make the arm active, still not a single handled device, but it allows room for the mechanism to control Z axis height. If you give it force feedback, you would no longer need a counter balancing spring, the piston could handle all functions of lifting the arm.
 
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