How to choose a motor to rotate a large mirrorless camera 360°?

Using Arduino Motors, Mechanics, Power and CNC
1

I want to mount a motor on my tripod head and my camera on it.

Ideally it should run on a 12 volt (5Ah) battery or less, be able to spin constantly on both sides and at variable but low speed. If possible, it should be silent.

I have no experience with motors, I tried searching Google, forums, etc. but I still don't know how to choose the best option for these needs.

The camera wouldn't need to be tilted, so the weight distribution shouldn't change drastically.

If you have any recommendations or sources I could read, it would be really appreciated!

Thanks!

2

We need more information and numbers not adjectives. How slow is slow? How much weight?

How much torque is required? How fast? Is precise positioning required? How will it be controlled, potentiometer, wireless? What Arduino board?

Once you find a motor you will need motor driver. Choose a driver based on the motor rated current and motor stall current.

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3

That is called a pan platform. Check Servocity.com for some examples. At absolute minimum, you need to specify the total weight of the load. Up to 100 pounds for this one:

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4

What does this mean in the real world?

5

For how long time?

6

Thanks!

Speed: 1 turn in 80~90 seconds up to 1 turn in 5~6 seconds or close to those ranges.

Weight: 4 kg max.

I will need to be able to turn it x° (0~5° precision) repeatedly to take a photo at each stop to create a large panorama, but I would also love to vary the speed to start and end slower to get smooth panning videos.

I will control everything with Arduino first than I'll control it from my phone.

I really don't know about torque... If the position of the camera+lens is important, for panoramas the camera would be attached vertically (portrait orientation, the lens would be a bit higher) but horizontally for videos.

:v:

7

YOU ALSO need to wait for the vibrations to stop before taking a picture. Every time you start a load and stop a load, the load oscillates.

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8

Thank you! At first I thought I could just buy a Nema 17 and attach my camera on a plate over it...

9

Yes! I already tested sensors for that, I will also use it for long exposures to cancel the shot before the end if I detect vibrations (from the wind sometimes...) over a specific level.

10

Sorry :sweat_smile: I mean I want to be able to stop the rotation and start immediately after in the other direction.

11

If you want to control the position you will need a stepper (like you said) or DC gear motor with an encoder. if it were me building a battery powered project, I would go with the DC motor. Steppers are not very efficient so not as good as a DC gear motor for battery power.

Whichever you choose you will need a way to "home" or zero the motor at program startup to establish the initial position.

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12

Very good question... For some time-lapse, it could last many hours but could only turn a little bit each hours. So the motor could be "sleeping" most of the time.

Else, less than 1 hour.

13

Thanks! I will read about both tonight :ok_hand:

14

With steppers, most drivers have an enable input so that you can turn off the driver output stage to save current. The problem is that that removes power from the motor so it may not hold position. A DC gear motor, because of friction in the gear train, will better hold position with power off. That is why the DC motor is better for battery power.

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15

Check out Pololu's line of gear motors.

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16

Do you think something like this one would be too much?

"64 counts per revolution of the motor shaft, which corresponds to 9600 counts per revolution of the gearbox’s output shaft."

I understand why they say 9600 (150:1) but I guess I can only read the "steps" of the motor shaft?

17

Okey, not strictly specified.
Using power down thinking, especially for the motor, will pay off.
As other helpers already told, use DC motors. A few sensors like home switch and a position sensor, are low, or no, power consuming devices.

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18

Thank you, now I know in which direction to look :blush:

19

Only if your DC motor is driving a worm gear. All others will require constant power to hold position.

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20

Will its highest speed be enough for your use (1 turn in 5~6 seconds)?

I do not understand the question.

A 150:1 gearbox is not going to be easy to backdrive. Admittedly easier than a worm drive, though.

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