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Need help with DC motor speed controller

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greener

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Need help with DC motor speed remote controller

Hi guys, i need helps with this stuff.
Before that i must say honestly that i don't have many experience in electronics. Yes i've learn some basics in schools but i'm not interested until now. Ok that's enough, let's move on.

I have a plan to make a DC motor speed controller (actually it is a remote controller). Actually it is a 3V toy car's motor.
I want the motor to run in simply two speed. But i don't know how can i remotely control it. I imagine that the controller only have one(or maybe two) button. So if we push the button, the motor will change it's speed (i.e. fast->slow, and otherwise). I suppose mayb i can use a tv remote or even a car door remote (if i not mistaken, both of it use infrared right?) to send the signal. But i have no idea how to do that, how can the car catch the signal, and how to process the signal.

So anyone can help me please?

Btw this forum is cool. I'm even more interested in electro after read the threads. Its like a silly lil kid who like firecracker come to a big firework festival lol.
 
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If you have no experience in electronics then it seems unlikely that you've sufficient skills to construct what you've described from discrete components unless someone provided a design with a step-by-step tutorial. The good thing here is that you've found a reason to to build your skills set and you can do that a step at a time. What you might do is purchase the remote control for that application then tinker with just the dc motor speed part.
 
The rpm of a dc motor depends on the load. For a given input voltage the rpm will vary as the load varies. That may not bother you but if you actually expect the rpm to be relatively constant then your motor speed controller will be more complicated.
 
Yeah may be you're right, but i'll try it first.

stevez said:
The rpm of a dc motor depends on the load. For a given input voltage the rpm will vary as the load varies. That may not bother you but if you actually expect the rpm to be relatively constant then your motor speed controller will be more complicated.

Yes, that's my guess. Coz when i run the motor with just 1 AA battery it is much slower. So how about making a simple circuit to control the battery use? Push the button to make it run with just one AA, push again to make it run with 2 AA, is it simple enough? But how about the remote controller? All i need is a one button remote controller.

Btw thanks for the advices
 
well i have something like this not exactly what your'e looking for but its good
wait il post a scymatic(sp?)
 

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hmm, i don't really know about electro scheme yet, but it seems it is not actually what i needed.

But thank you maor.

May be as i doing this, it will be better if i learn basics from the very begining too >_<
 
Does it have to be remote control?

If not, it would be easy to connect a SPDT switch to the batteries.

the center terminal would be one motor lead. The other 2 would have the one battery or the 2 battery connection, with the other lead connected to center.

If it has to be remote control, good luck! that would be difficult for a beginner (as I have yet to learn that)
 
I have some questions here. Hopefuly someone will shed some light

1.
stevez said:
The rpm of a dc motor depends on the load. For a given input voltage the rpm will vary as the load varies...
So the voltage will give effect to the motor's RPM. Then what about the current? What will it effect to?

2. As i learn the basic, i found that capacitor can role as additional battery, is that right?

3. So we can increase voltage using capacitor (i learned this from this forum). But with the voltage increased, won't the current be decreased?

4. Is there any way to increase/decrease the current?

I hope someone can help me. And thanks in advance

it seems i still have so much things to learn
 
A DC electric motor has a high RPM and a low current without a load. It has a low RPM and a high current with a load.

You can slow it down and reduce its torque by reducing its supply voltage. Switching two rectifier diodes in series and in series with the motor will reduce the voltage to the motor by about 1.4V.

If you are talking about making your own radio control system then buy a radio-controlled car.

A capacitor stores a very small amount of power. A battery stores a huge amount of power. A very big difference so you can't use a capacitor instead of a battery to power a motor.
 
You're better off using PWM for speed control because it doesn't reduce the torque as much.
 
@audioguru

I think a radio controlled car is very much more complicated than the one i need, sir. All i need is a one button remote. It's like click the button and the car will go fast, click again and the car will go slow.

@hero999

So we can use PWM to control and stabilize the motor speed, right. Coz that's what i got from the reading.

------------------------------------

"Capacitor passes AC current and hold DC current" What is that "passes" and "hold" mean?
Is the "passes" mean that the capacitor will let the AC current trough and save some of it's energy?
Is the "hold" mean that the DC current can't go trough the capacitor, and may be the capacitor get overheat and then blow up?

------------------------------------

I've read some topic that i think it have some similarity with my project here.
https://www.electro-tech-online.com/threads/cheap-on-off-remote.31246/

I think the difference is that project is a cheap on-off remote and mine is like a cheap fast-slow remote.

So, is it same?
 
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