Floating Gimbal Movement

[Enrico Grillo]

I am a very new operator, and I am flying a knockoff rig from a brand I do not care to write down here because I am not yet in a place to drop $5,000+ on a rig.

 

I am aware that running a cheap rig is not helping me, however given the parameter that it is what I have to work with right now, I'm trying to track down the likely cause of an issue I am seeing: I have my rig built with a fairly light camera (though I have tried adding weight to the stage with no real change). I balance the sled static and dynamic, drop is a healthy 2 seconds, etc. Everything feels balanced in general, but when I actually fly the sled it has a tendency to lazily drift a degree or so back and forth when at rest. I can get the arm fairly steady in a stationary position but the gimbal just kinda keeps drifting around. The drift is more or less circular, not listing towards a specific direction, and everything else seems to match what I have seen in demos and guides. I would intuitively think that this was caused by a top-heavy sled, but the sled drops correctly and this happens even when I fly almost no weight on the stage or with a lot of weight at the bottom of the sled.

 

Is this likely just the result of a cheap gimbal, or are there common causes of this behavior in how the rig is built and balanced? I don't trust this rig to perform like a real steadicam, but I also don't want to bake operator error into my practice and just blame it on cheap equipment.

[David Parrella]

Hey Enrico!

Don't worry about what type of rig you have, we're all just trying to do the best we can with what we have access to :) It may be more helpful for us to see some pictures or a video of what you're experiencing. A few things that I'm curious about off the bat that could cause some effects you're seeing:

How much distance is between the top stage (camera) and the gimbal? Typically, you want to have the gimbal / center of gravity as close as possible to the top stage, if there's a large amount of post between the top stage and gimbal, what you described can happen quite easily.

Second, does this happen when the sled is balancing on a stand or the dock?

[Enrico Grillo]

On 9/6/2022 at 3:16 PM, David Parrella said:

Hey Enrico!

Don't worry about what type of rig you have, we're all just trying to do the best we can with what we have access to :) It may be more helpful for us to see some pictures or a video of what you're experiencing. A few things that I'm curious about off the bat that could cause some effects you're seeing:

How much distance is between the top stage (camera) and the gimbal? Typically, you want to have the gimbal / center of gravity as close as possible to the top stage, if there's a large amount of post between the top stage and gimbal, what you described can happen quite easily.

Second, does this happen when the sled is balancing on a stand or the dock?

Thanks for the input! I will try to capture some video when I get a chance. I am having to lower the gimbal a lot because my sled is bottom-heavy enough to give me sub 1-second drop times. I'm flying a fairly light camera, so I've added weight to the top stage, but even with that I am easily having to put four inches between the docking collar and the gimbal. I can try to add more weight to the top stage and reduce whatever I can on the bottom of the sled to see if a higher gimbal eliminates some of the sway/drifting I am seeing.

 

On the balancing pin, the sled does come to a stop, however it isn't always perfectly level. It leans just a tiny bit off center, and when pushed, doesn't seem to reliably stop at the same place each time. I don't feel resistance as-per-se in the gimbal, but this contributes to my suspicion that the gimbal could be a problem. I just bought some new bubble levels to check leveling of the sled as I don't trust the ones built into the sled – they seem imprecise, so I need better measurement before I can say for sure how accurate the balance is on the pin.