Plate that rotates every 30 seconds

[Petronius]

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.

 

[srizbf]

... 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.

you want the plate to rotate 1/7 of its circumference or
move(linearly on a surface ) a distance of 1/7 of circumference ?

you have to clarify before the suggestions are given.

 

[Warpspeed]

A divided down crystal oscillator driving a stepper motor should do it.
Exactly 210 seconds per revolution should be pretty easy.

How about a 32.768 Khz watch crystal fitted to an MC145151 frequency synthesiser chip ?
That contains the oscillator circuit and a fully programmable 14 bit divide by N counter with the directly divided down crystal output available.

That divides down to 2.000 Hz minimum, but that could be increased in very small increments to drive a stepper to exactly 210 seconds per revolution.