RC altinator... posible?

[Beattie]

I was thinking that it may be possible to make a altinator out of a small electric engine... does it work that way? if you spin the crank on a electric engine, does it make power? if it does i wa thinking you could hook it upto you flywheel(like on the rc superchargers) and it could carge batteries for extra things like lights or even the receiver batteries....

I donno if it would work, just putting it out there :hammer:

 

[mhasson]

Possible alternator

It is definitely possible to add an alternator to a Nitro RC car BUT it will be added weight for the magnets, coil, and electronic voltage regulator. Generating electricity also consumes power. Charging the batteries while you drive could use .02 HP. For racers that may matter.
I've thought about it. I'd buy one in a second.

Here's what else I'd do. (while we are dreaming)...

Connect a temperature probe to the glow plug. When I turn on the car the glow plug gets hot until the engine is started, then shuts off. If the engine stalls, the plug gets hot again. The battery would charge when the motor was running. On electric start vehicles, you could start them via remote if your receiver battery pack has enough juice.

 

[ToRqUe]

Beatti,
If u ever do it put some pics. up it sounds like a good idea.

 

[vbgagnon]

I think the altenator would b one hell of an invention. I'm not sure how the electric engines work tho. good luck with it.

 

[Rolex]

Just to keep the explanations clear, there is no such thing as an electric "engine". If it's electric, it's a motor. Why Nascar drivers still call their engines "motors", seems to be a southern thing. Engines run on fuel, either piston or jet, and motors are electric.
A motor turns because electric current flows through its' windings and creates a magnetic field, attracting it to the fixed magnets. Spinning the motor has the reverse effect.......the coils, passing through the fixed magnetic field creates current, so yes, it's possible to do. What the speed needed would be, and what type of motor you need, plus a voltage regulator, would make for an interesting experiment.
Keep in mind though, that the engine turning the motor, would be a trade off in power.

 

[fisherman]

Yeah, i called my 2.5 engine a motor and my dad told me that motors are electric and engines have pistons. Ever since then i have goten it right. Any way i thought about it too, and thought well there are some radios that have things you wind to give it power just like an alternator for a 1:1 engine so you could try to find one of those to hook up, but they only put out like 2.5 volts so it wouldnt charge it that much. IDK you could try it. let me know if you do invent it.

 

[olds97_lss]

There's already an alternator that exists. It's for large rc aircraft. I emailed the company and they said it's relativly fragile and requires more space than rc's allow. I can't remember the name of the company. I may have a link saved at home...

 

[HUEY]

try this site http://www.sullivanproducts.com/GenesysMainFrame.htm

 

[Beattie]

I doubt I'm going to make it. to much $$$ and I'm not exparienced with electrics and stuff. You guys can try it tho :shrug:

 

[olds97_lss]

try this site http://www.sullivanproducts.com/GenesysMainFrame.htm

That's the site I was thinking of.

 

[canadian-mgt]

interesting idea,but it would be alot more trouble than just bolting up a motor to run off the flywheel.the electricity coming out would be AC so you would need a rectifier and a voltage regulator to make it work.at the speed the engines in rcs run it would probably produce too much current also.don't let that stop you from trying it though,if you're good with electronics you maybe able to pull it off without too much trouble.

 

[Diver6127]

For those of us that race our r/c's, it would be impractical. We need to save weight and to add that much just to keep our receiverpacks charged through a 5 minute heat and 15-30 minute main would prove to be counter productive. Peak chargers and portable power (ie prestone jumpstarter) would prove to be more practical.

 

[olds97_lss]

I thought about it awhile back, but it's been so long since college that I don't remember how to build a rectifier or a regulator... I've built both out of components, but I can't remember now... Isn't it sad that I've forgotten what I've learned but yet I'm still paying the loan...

Anyway, the thought of it came to me during the winter. We all know how long NiMH bats last when it's 15F degrees out. I was tired of replacing my batteries every hour vs the 3 hours they lasted in the summer.

My idea was to mount a couple very small magnets, not unlike the one in the venom speed meter, to the back of the flywheel. Then make a couple small inductors to mount on the engine mount bolts that allowed you to slide the inductor out to the magnets, or at least damn close to them. Due to the high rpms (as canadian-mgt said), it wouldn't take much of a magnet or a coil to create voltage. Then it would just be a matter of creating a regulator and rectifier. You could build that on a circuit board the size of your big toenail. Very minimal weight added to the vehicle.

When I buy a house and have a garage that I can mount one of these little engines on, I'm going to give it a shot just to see. Maybe I blow up a battery, maybe it does nothing.

However, I remember back in jr high school, at a lame science fair, a kid made a very crude generator out of copper wire (hand wrapped inductor on a pop-cycle stick) and a few magnets. It was big and bulky, but it was enough to light a 1.5v light bulb with a 800 rpm electric motor running the generator.

Granted, it defeated the purpose by using more energy than it put out, but the theory is definatly sound. My thought is, if you can rig something that weighs under a couple oz and doesn't have any mechanical contact with the drive train, why wouldn't it be durable? No rubbing wheel, no belts, no gears, just magnets epoxied to the back of a flywheel and a 1-2mm air gap to the inductor. Nothing to wear out or break down.

Why the ones on the website you found were so large, I do not know. Maybe it was to help make them stronger and more stable. Maybe it's due to the lower RPM's that 4-cycle airplane engines run. I don't know.

When I try, I'll let you all know, burned up batteries or not.

Now why can I remember something that was 14 years ago and free vs. something that cost me 40K and was 8 years ago still boggles the mind.

 

[oldcars]

I made an alternator for my kyosho optima mid, i asked my dad about turning a normal motor if it would make power and he said the wire wasn't wound right bla bla bla so i got one of those dyno charge flashlight/stereos i took the little motor charge thing out and i made a little cog(whatever its called) and i fitted it to the belt drive i got a battery tester out and i tested the output of the charger and it was kinda small charge i didnt know where to connect the wires leading from the charger too so i took it off i still have the assembly but mabe i should of connected those wires right to the motor so it would give(the motor) some of the lost energy from the belt. I'm gonna put the thing back on and try it tonight.

 

[kwong2001]

Connect a temperature probe to the glow plug. When I turn on the car the glow plug gets hot until the engine is started, then shuts off. If the engine stalls, the plug gets hot again. The battery would charge when the motor was running. On electric start vehicles, you could start them via remote if your receiver battery pack has enough juice.

That's actually a really good idea, and you could design one pretty easy as well as market it. The only problem is figuring out how to tell the unit the engine is started.

You could easily design a remote glow igniter that runs off of the 3rd channel in the receiver, it could have a simple switch to turn it on, then when the engine started, just turn it off.

I'll bet you could probably make one pretty easily.

 

[phootbag]

I made a generator for my Tmaxx. I used a normal 7.2v RC racing motor. I attached the motor with a mount to the Tmaxx transmission and drove it with the main spur gear. At about 15,000 rpm I got something like 14V. I regulated the charging with a small light bulb. This doesn't regulate the voltage it regulates the current. You can pretty much charge any battery with as high of a voltage that you want, it's the current that really overheats a battery. The electric motor puts out DC but you have to use a rectifier to keep the batteries from pushing back and trying to turn the motor as the motor is pushing to charge the batteries. I used a small rectifier diode from radio shack. A capacitor at the motor helped with noise. I ended up finding an 8 volt regulator and used that. The light bulb worked, this was just a little neater.

And I found a small lead acid battery about half the size of a pack of ciggs.

 

[micro07]

id deff. buy one

 

[wdavidhicks]

An alternator is an alternator because it's more than a generator. A generator supplies power by means described by posters above. An alternator will disconnect itself from the charging circuit when its RPMS's fall below what is required to charge through its connected circuit. At idle speed you don't want to drain the battery as it tries to run the alternator as a motor. Alternators have a built-in voltage regulator to prevent this.

Think of this while you develop your ideas. Power generation for low voltage DC operated devices is rather fruitless.

A rectifier bridge is nothing more than four diodes converting AC current to DC current. Without a filter (capacitors and resistors) this current is still alternating with all sine waves above zero volts DC.

A battery provides a flat-line DC voltage.

An AC adapter provides DC voltage calculated at a root mean squared. This is peak AC voltage divided by 1.7333333. The AC voltage for a rectified 9VDC adapter fluctuates between 16 VAC and 0 VAC.

480v 3-phase power can provide 277 single phase power by bringing one leg to neutral. (As long as the electrican brings a neutral leg to the box)

I know this poop is boring... I'm tired too...

 

[MonsterCowpower]

An alternator to recharge cells,yes could be done.The battery pack only powers the receiver/servos.The recharge rate would not be very high.

Also I think a 380 type modified for the task motor used as a the alternator would be plenty.From there a voltage/current regulator would recharge the cells.

But even a small 380 size motor adds weight and DRAG on the engine.Drag and weight no racer needs.

Better off using cells and changing(recharging) them when needed .

 

[Clintd]

An Alternator and a generator are to entirely different things As far as design. An Alternator has no permanent magnets, has permanent contact brushes (no slots on the commentator) and produces AC current. The AC current is then fed through a rectifier bridge which is basically 3 diodes to make it DC. Then the DC current is fed through a regulator to bring it down to about 13.8V DC. The advantage of an alternator is its ability to produce power at low RPM’s. The disadvantage is it need’s an external power source to energize the field (no permanent magnet’s). Once the field is energized it no longer need’s external power. A generator is exactly the same as an electric motor. (Slotted commentator permanent magnets ECT) as a matter of fact some early farm machinery used the generator to also start the engine. The only advantage of a generator is that you didn’t need power to make power. (As long as it’s turning fast enough it will produce power). The disadvantage is it needed a lot of RPM’s to produce power. The DC current was fed through a regulator so that it wouldn’t act as a motor when it wasn’t rotating fast enough. So at idle it was basically turned off.

I used to have a 1968 Plymouth fury III . (At that time they had alternators and mechanical relay type regulators) and one time the regulator got stuck closed. It boiled over the battery and blew out every bulb in the car except the high beams and the high beam indicator. Boy did that suck.