How to keep a DC motor driven platform steady

[atferrari]

I have kind of a small round board atop my bot, spinning driven by a DC motor. When the encoder shows that it has turned the exact required amount, I want to keep it steady unable to turn anymore until next order. External forces exist that could make it to rotate in one sense or the other.

Can this (breaking ?) be achieved with a common DC motor or should I resort to a modified RC servo? Whatever helps in saving power, much better.

No previous experience. That's why such a basic question. :?:

 

[bloody-orc]

use wormgear. it makes turning very slow, powerful and stiff. or put a brake on the motor (give v+ on poth leads of the motor)

 

[atferrari]

Mechanical solutions to be avoided

I prefer braking by shorting terminals. :idea:

 

[Nigel Goodwin]

Re: Mechanical solutions to be avoided

I prefer braking by shorting terminals. :idea:

That's what 'bloody-orc' said!, but I think the translation made it a little confusing?.

 

[atferrari]

Got it, Nigel!

In fact I was confirming that I understood what he said. :!:

Even I recall there is a chip (sure there are many!) that will do the shorting if the input signals are properly selected. An H bridge, perhaps?

 

[Nigel Goodwin]

Re: Got it, Nigel!

In fact I was confirming that I understood what he said. :!:

Even I recall there is a chip (sure there are many!) that will do the shorting if the input signals are properly selected. An H bridge, perhaps?

Yes, and not just a chip, a discrete H-bridge will do it as well (assuming it's designed to?) - in fact the specific way he worded his response was directly refering to an H-bridge system.

 

[theinfamousbob]

This might be a bit more than you need:

https://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=62033&Row=361165&Site=US

I am going to be using one for a maze robot for competition and am tying it in to an OOPic.

It should do everything you need, and can take a bit of current.

Hope this helps!

 

[atferrari]

Link doesn't work

Hola Bob,
Your link is not working. Could you help?

Gracias.

 

[theinfamousbob]

Sorry!

The part can be found at:

**broken link removed**

Hope that works!

-Infamous

 

[atferrari]

Got it. Thanks

A good one. Gracias.

 

[theinfamousbob]

Glad to help.

 

[addyismad]

use l293dne chip.....
gives kinda regenerative braking for a particular combo of inputs...