Turning Nokia hhd into precision motors for micro camera gimbal

[avbs18289]

Hello, I am trying to build a micro gimbal that can stabilize ultralight cameras, yet retain higher precision that standard servo gimbals of these gimbal’s design. The pico analog 5V camera that some company’s offer weigh about 1.4 grams, and if I double the weight as a capable of two cameras with one as backup, the gimbal would have to carry at most 3 grams.

I would want to use the hhd out of the Nokia 91, and use a rotary encoder so I can turn it into a rudimentary brushless motor. I was wondering if anyone knew if any rotary encoders that are size of the components in the spinning axle part of the nokia 91 hhd, pictured here:

https://www.aliexpress.com/item/1005004080808553.html

Secondly, beside building a diy rotary encoder of this scale, or purchasing one, I have one more issue to solve. Does anyone have any links for sliprings of the scale of hhd?

I am trying to find the smallest sliprings available, they only need to have power ground, and one third (wire analog for video). Building one could be an option, however I was wondering what the available, that have miniature form factor, and are very light weight. Any product selection recommendations or advice would be appreciated, thanks.

I have considered using brushless motors, but the lightest motor I could find is 1.4 grams, and I would like to ask if this project is feasible, to get precision control out of the Nokia 91 hhd drive, for controlling a nano sized gimbal.

 

[rjenkinsgb]

Look for an AS5048A module - the IC is a magnetic angle encoder - it needs a tiny magnet with N-S across the width of the rotating part.

You can get them on a small circular PCB for easy mounting and wiring.

That general type of sensor is the smallest you are likely to get.

Slip ring couplings - the smallest is under 6mm diameter x 9mm long:

Miniature Slip Rings - Samll Capsule Slip Rings | Moflon

Miniature slip rings are small electrical device(OD<12.5mm) which can transmit power/signal from static to rotational components, combine small size and high performance, making them ideal for video transmission and other challenging, space-critical applications.

www.moflon.com

Whether the overall thing is feasible is another matter; I doubt the HDD spindle motor will have enough torque, somehow, as it is intended just to run the platter as a constant speed, rather than control any real load. Newer purpose made motors will likely have vastly higher torque.

Mass-wise, a full gimbal setup has three cascaded motors at 90' to each other - so the first stage has to carry the mass of both other motors and the framework, as well as the camera load.

The last stage has just the camera and its mounting frame.

Also, for maximum possibly stability, you likely need an IMU in the camera section to sense movement and orientation at that point?

 

[avbs18289]

I was planning on using a dual imo system for the nano sized gimbal (I assume it would have to be a custom imu given the small size of the gimbal), in combination with open bcg gimbal software.

Thank you for the suggestion about the motor weight, I didn’t take into consideration that the yaw motor needs to have enough power comparatively.

 

[avbs18289]

 

[avbs18289]

That was an idea of mine above, for a GoPro sensor and aio 5.8ghx fpv cam, for a dual operator setup for videography/ general use on rc planes/ quadcopters. I was thinking the Nokia might not have enough torque for the above setup, but might do well with a single pico sized fpv camera.

 

[avbs18289]

Good considerations, thank you.