# Plate that rotates every 30 seconds

#### Petronius

Joined Dec 3, 2015
1
I have a project I would like to create that involves moving a plate around an axle every 30 seconds. I would like the plate to move 1/7 its total circumference every 30 seconds. While the mechanism may be electronic, it could also be accomplished by a spring. Can anyone give me any suggestions about how to realize my project?

Thank you.

Joined Jul 18, 2013
20,419
A little more detail on the mechanics involved or clearer concept?
Max.

#### KeepItSimpleStupid

Joined Mar 4, 2014
4,004
Not knowing much about what you have to do, I've done something similar for a filter wheel. If you can notch the edge, there's an easy way. Place a microswitch so the motor will stop when it's in the depression along the circumference.

To make the motor move, you have "short out the switch"

What I used, was a controller that was able to tell if the motor was "moving" or stopped. I then used two hall effect sensors to actually determine the position.

The good stuff, like what you need to size the motor would help. Big difference if it's a figurine or a human. The power source matters too.

For what I had to do, an AC synchonous motor worked really well. The RPM is constant and they basically stop instantly.

So, in the case you want, you can use two timers:
a) sets the width of the pulse to start it rotating and get it out of the way of the switch that stops it.
b) And one to set the interval.

There are a lot of unknowns in your post. I took it as stop every 1/7 of a circumference, but you could mean continuous rotation. My post may or may not be any help based on the limited amount of information to work with.

#### mcgyvr

Joined Oct 15, 2009
5,394
Fixed RPM motor + Geneva drive mechanism

#### djsfantasi

Joined Apr 11, 2010
6,336
Connect the axle to a stepper motor, driven by a dedicated circuit or a microprocessor. If the load is appropriate; if the load is not too heavy. Design a feedback device for position to correct errors in the drive. Like a grid on the edge/bottom of the plate and a photosensitive or notch/micros witch as KISS mentioned.

#### mcgyvr

Joined Oct 15, 2009
5,394
obviously more details are required..
weights..speeds.. motion profile,etc...

#### KMoffett

Joined Dec 19, 2007
2,821
Maybe this will work for you. You need 7 "somethings" (mechanical, optical, magnetic...) to trip the NO switch at the 7 stop positions.

Ken