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Rotating one motor using another manually?

#1
01-01-19, 03:11 PM
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Join Date: Aug 2018
Location: Israel
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Rotating one motor using another manually?

Hello, I've came across the following videos recently:
https://www.youtube.com/watch?v=1zwboVgzugw (can watch from around 1:30), and this: https://www.youtube.com/watch?v=2qVNxvnkGug (its pretty long, around 7 minutes should somewhat describe it).

From what it looks like in the second video, he connects 2 motors plus to minus in opposite directions, and then when he manually moves one motor, the other moves as well.
I'd like to make something like that, but I just want to make sure before I do, am I missing something here? Is it really that simple? Just taking 2 motors, then connecting them plus to minus and it will work?

On another note, can someone explain about it? What is the name or principle behind this mechanism?

Thanks a lot!

#2
01-01-19, 03:43 PM
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Location: welland ontario
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It looks like two DC motors.
A DC motor and DC generator are basically the same thing. Apply power and it runs like a motor. Spin the shaft and the unit generates power.
Basically what he is doing is spinning one motor and it is acting like a generator generating power. That power makes the other unit act as motor and spin. Spin the opposite direction and the +/_ generator reverses and the motor runs opposite direction.

#3
01-01-19, 03:52 PM
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I'd like to make something like that,
Why ? What would you do with that ?

#4
01-01-19, 04:01 PM
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Join Date: Aug 2018
Location: Israel
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Originally Posted by joed
It looks like two DC motors.
A DC motor and DC generator are basically the same thing. Apply power and it runs like a motor. Spin the shaft and the unit generates power.
Basically what he is doing is spinning one motor and it is acting like a generator generating power. That power makes the other unit act as motor and spin. Spin the opposite direction and the +/_ generator reverses and the motor runs opposite direction.
So if I understand it correctly, its really as simple as I described it right?

Originally Posted by PJmax
Why ? What would you do with that ?
It would've been nice to get an answer as well, but I want to use it to control a telescope focuser without touching the telescope, and it looks like an awesome way to achieve that

#5
01-01-19, 04:07 PM
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No.... you'd want to use servomotors. They are small motor and gearbox combos. Designed just for what you want to do. In the link is just one example.
DC servo motors

You can search "small dc servo motors ebay".

They run on low DC voltage. You could use a spring loaded center off switch to reverse voltage to it for in and out motion.

#6
01-01-19, 04:12 PM
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Join Date: Aug 2018
Location: Israel
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Originally Posted by PJmax
No.... you'd want to use servomotors. They are small motor and gearbox combos. Designed just for what you want to do. In the link is just one example.
DC servo motors

You can search "small dc servo motors ebay".

They run on low DC voltage. You could use a spring loaded center off switch to reverse voltage to it for in and out motion.
Well yeah thats what I meant, what you sent is actually exactly what I already ordered(well except for the actual seller).
Can you elaborate on the "spring loaded center off switch to reverse voltage to it for in and out motion.", and is that different than what showed in the videos?

#7
01-01-19, 04:42 PM
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This would be reversing circuit using DC power.

#8
01-01-19, 04:50 PM
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Join Date: Aug 2018
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Originally Posted by PJmax
This would be reversing circuit using DC power.

Attachment 100029
Thanks! I actually managed to find some information about it meanwhile, thats actually a great idea! But due to the fact that sometimes the motor movement needs to be so small, I think that option might not be the best, but I took that idea and thought of something very similar, and came across tactile switches, which looks just awesome, I've also seen this: https://www.aliexpress.com/item/High...e-1d244538c3f4
Which seems exactly like what I need, what do you think?

#9
01-01-19, 05:29 PM
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Shouldn't need a switch. Turning the motor the opposite direction should reverse the voltage generated.

#10
01-01-19, 05:48 PM
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Join Date: Aug 2018
Location: Israel
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Originally Posted by joed
Shouldn't need a switch. Turning the motor the opposite direction should reverse the voltage generated.
​​​​​​​Yeah, but I think it will be easier to use that way, so why not I guess ^^

#11
01-01-19, 09:43 PM
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deleted .............................

#12
01-01-19, 11:39 PM
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Location: Israel
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Came across this thing: https://www.youtube.com/watch?v=QmLQMQ-eAZY what do you guys think? o.0