Servo vs. Brushless Gimbal

The intention is to try both. I have started with an assumption that servos will provide the best general-purpose support among other advantages, but the DJI FPV drone uses a brushless gimbal for camera pitch so my concerns may be invalid, regardless of that here are my initial thoughts on it.

General Application

A concern I have for a brushless setup is that brushless gimbals need to be ‘balanced’ to perform properly, this means that it would need some kind of balancing system to accept different action cameras or to be used without an action camera. I have concerns that producing the same system with a brushless gimbal would be difficult, especially for a ‘general solution’ that’s simple to implement.

Reliability and Durability

This is an obvious win for the servos, at least for a big servo, the current setup I am using consists of a very strong gimbal printed from TPU and a 20kg/cm servo, connected by a 1mm steel linkage, which basically means I’ll never damage the servo, as the linkage will bend long before the servo was strained, the linkage can be bent back in a few seconds and in my experience that’s usually the only thing that takes damage.

In the case of a brushless gimbal, it is far less durable, but it does have some notable advantages.

Natural Movement/Video Quality

A shaky camera is almost never what’s desired out of drone, we like smooth movement in video and this will be the ultimate deciding factor for some applications, unless both could produce natural movement…

Servos are twitchy, I didn’t realize how twitchy they were until I started using them for this application, I was told by my engineering consultant (friend) that it was due servos using potentiometers, which have margins or error, and that servos are basically innately twitchy due to that. This is true, however I hoped there were ways around this. Early Testing and designs didn’t show promising results, no one likes a shaky camera.

A brushless gimbal is a proven method for stabilizing a camera and producing smooth movement, in the case of a FPV drone it could even serve a secondary purpose of stabilization. If it is possible to make a brushless gimbal that could provide a “connected” feel, be durable, reliable, able to be generally and simply applied and to existing systems, and be cost effective, then I started down the wrong path.

Conclusions

Before starting to build and test brushless gimbals I intend to thoroughly explore solutions that utilize servos, as even the most complex setup will be far more simple than a brushless solution. If only there were servos that weren’t twitchy… I did a lot of testing with a lot of expensive servos (consider Supporting Medlin Drone) and made an important discovery.. check out Finding the Right Servo in the Wrong Places.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: