Technic Technique

[Athos]

Since everyone was so helpful with my last movement question, I have another.

I am trying to work up another movement feature in a MOC, where it will have a werewolf on one side of a wall and a regular person on the other. What I'd like to do is have the figures turn around at an interval, so for one period there is the regular guy and then for the other the werewolf, so it looks like he has transformed. I have no idea how to make this work with just a regular motor though (maybe some kind of a timing chain?).

If that is too confusing: basically, what I'd like to have is a gear make a 180 degree turn and then stop for a few minutes and then do it again.

Steve

[matthewclso]

Perhaps you should consider going it with the Lego Mindstorms EV3 programmable brick and EV3 servo motors.

[Blakbird]

Sounds like you are looking for intermittent output motion from a continuous input.  Have a look at Geneva mechanisms (search on this forum).  They achieve such a result.

[J_C]

or mechanism from "cuckoo clock" is basically what you need. it makes a move (whatever you define it - this case rotation) at repeated periods of time (length of which can also be altered by your design)

It can be done, ain't no simple task thou... 

Edited November 14, 2016 by J_C

[Athos]

Thanks for the tips. I have been (kind of) enjoying learning about the mechanics of this stuff.

Steve

[Captainowie]

Some of the larger gears have off-centre axle holes. You might be able to get away with just having a gear loaded on an offset axle that only engages with another gear for a short time each rotation. You'll probably need to have some kind of limiter to keep the final output to 180 degree increments.

I'm sorry that I've described that poorly - if it's not clear let me know and I'll have another go.

Owen.