Rotating Slowly?

Hi,

I am trying to make a lamp shade that rotates slowing around its base (5-10rpm) and my question is what kind of motor should I use?

I was thinking about either:

A continuous rotation servo, but i think i read on those you can control the direction, but not the speed

A small stepper motor, you can control the speed of those by slowing down the steps-sent

A dc-motor, but i read some conflicting things about how to control speed, PWM vs Just reducing voltage, and i’d rather not deal with figuring out gear ratios.

Im looking for something easy to set up without requiring a lot of components, and ideally since i have some esp8266 and teensy’s laying around, 3.3v compatable.

Thanks!

I'd say one of these if you don't want to deal with gearing:

A continuous rotation servo, but i think i read on those you can control the direction, but not the speed - control speed by controlling how fast you command it to the next position, and make the next position not far from the last one so it appears to move slow & smooth.

A small stepper motor, you can control the speed of those by slowing down the steps-sent

If you want constant rotation speed just get a synchronous mains gear motor, they are standard
parts and commonly used for such purposes and last decades (if you keep the bearings from drying
up every so often).

If you want speed control any small DC gear motor with enough reduction gearing. But don't expect
a long life from a small brushed DC motor.

I am assuming the load is constant.

Stepper motor will move in very obvious steps, although microstepping will help. If you don't need
repeatable position control you don't need a stepper (and they are more power hungry).

If this is for a lamp shade I'd guess that noise might also be a concern.

If it is I'd suggest that stepper motors might be the best approach as they will be the quietest, are likely the most adjustable ( via programming ) and will last the longest. A stepper with something like 180 or 200 steps with a 1/16 step program.

I've had continuous servos wear out over time when using plastic gears and the metal gears tend to be noisier.

Geared motors can also get noisy and it will be more difficult to adjust ( without PWM which can also create a frequency noise on some drivers ).

Maybe worth trying something like this. Only 64 steps per revolution for the stepper motor but each step is geared down by 1:64 so will be smooth enough for a lamp shade.

[u]Disco balls[/u] use a gearmotor.

A million years ago I had a lamp similar to [u]this[/u], "powered" by the heat from the incandescent bulb.

DVDdoug:
A million years ago I had a lamp similar to [u]this[/u], "powered" by the heat from the incandescent bulb.

I remember them, maybe a thing of the past now with LED becoming the norm. :frowning: