DC motor for paper model airplace

[roadkill367]

Hello all, I'm trying to help my neighbor's son, who has autism, which his paper model airplane. He would like to have the propeller be powered so he doesn't have to rely on the wind to turn it. My thought was to use a 12v DC motor and a 9 volt battery. The part which confuses me is what to use to control the speed of the propeller. He only wants it to turn slowly and he usually cares the plane with him around Disneyland. Any help with this project would be greatly appreciated.

Thanks it advance

Andrew

[Benta]

12 V motor and 9 V battery for a paper plane? Sounds to me like it would drop like a stone. Or am I misunderstanding "paper plane" here?

[robjodicarter]

I found these for you on amazing, I know that make a bunch of small light lithium batteries that last forever. You can put a pot inline to adjust the speed and a switch to turn it on and off.
Rob

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[roadkill367]

I guess you could say it's make more out of cardstock than paper. It's very sturdy but it's not meant to fly or anything. He just carries it around. The motor and other parts will sit on a balsa wood bottom.

[roadkill367]

What would I use to control the speed of the motor. Could I use PWM like this one from amazon (uniquegoods 1803BKW 1.8v 3v 5v 6v 7.2v 12v 2A 30W DC Motor Speed Controller (PWM) Adjustable Driver Switch)

https://www.amazon.com/gp/product/B00RYKR83Q?pf_rd_p=faa1d3e1-fadf-4279-ac2d-3096206e4690&pf_rd_r=FW60M3S4ZGCV3HXHH5G4

[robjodicarter]

Oh ok so how slow would you like it to turn? Would it be easier to just install regular AA batteries? No matter what you would need a potentiometer in order to slow it down, but that can be stored inside.

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[robjodicarter]

Yes perfect!!


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[flynwill]

Motor and battery light enough for a paper plane is a pretty tall challenge.

I got given one of these:

https://www.amazon.com/Original-Smartphone-Controlled-Airplanes-Conversion/dp/B00N8GWZ4M

For Christmas last year...  And my review would be it "kind of works".  But I'll admit I didn't invest a lot of time into trying to make it work.

[robjodicarter]

I think he has the plane just looking for the motor and battery. He is on the right track just needs to find out power source.
Rob

Motor and battery light enough for a paper plane is a pretty tall challenge.

I got given one of these:

https://www.amazon.com/Original-Smartphone-Controlled-Airplanes-Conversion/dp/B00N8GWZ4M

For Christmas last year...  And my review would be it "kind of works".  But I'll admit I didn't invest a lot of time into trying to make it work.

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[jpanhalt]

As a very long-time modeler, have you considered a rubber band motor?  Very light weight, and with the proper propeller blade, they can power for a long time (>45 minutes indoors).  Those are, of course, indoor models.  However, outdoor versions are available with less duration.  A paper outdoor model will probably not benefit from an electric motor; however, paper-balsa models will.  Very small motors from pager vibrators are available.  Wind speeds will have to be very low, and some skill is needed for construction.

If you really want a paper model, I suggest a balsa motor stick, paper model, and rubber band motor.

[roadkill367]

Here is what I have so far.

[AlcidePiR2]

https://www.kickstarter.com/projects/393053146/powerup-dart-app-controlled-paper-airplane-with-tr?ref=user_menu

[james_s]

It seems most of the people answering here are assuming a flying model while it sounds like what you want is just a display model with a spinning prop. You can get small gearhead motors that spin at a much lower speed than a direct drive DC motor. Cheap ones are available from China, I would suggest using a pair of AA batteries for power. Much cheaper than 9V.

[Ian.M]

Its going to have to survive abuse like the kid trying to turn the propeller by hand, so a gearmotor isn't a great idea unless you can arrange it so there is a friction clutch between the motor outut shaft and the propeller.

An alternative that wouldn't mind the propeller being held or manually turned while its running  would be a low voltage miniature stepper motor, + driver board and a MCU to generate the stepping signals, with PWMed current control to limit the torque.   It could all be powered from a single 18650 cell based USB powerbank, providing 5V for the MCU and motor, or 4x AA and a LDO regulator just for the MCU to limit its supply to 5V.   If you've done anything with Arduino, it shouldn't be too tough to get a suitable pulse sequence out of an ATtiny MCU, or use whatever low pin count, 8 bit MCU + toolchain you prefer. 

[james_s]

That's making it waaaay more complicated than is necessary. Lots of gear motors don't mind being turned by hand, gear motors have been used in kids toys for many decades.

[roadkill367]

Thanks for all the replies so far. The kid is pretty high functioning so I'm not worried about him doing anything with the plane he shouldn't. James S is correct that it is not for flying he just carries it around with him and would like the propeller to turn by itself as he does so. I have a small SODIAL 6-12V 3000 RPM Cylindrical DC Shaft Motor for Smart Cars already and so looking for the correct way to control the speed of the motor.
Thanks again guys.

[james_s]

If you want to control the speed of the motor the correct way is to use a PWM driver, this could be built around a small microcontroller or it could be built using a dual op-amp, or a 555, or any number of other ways. You'll probably have a hard time getting a 3000 RPM motor turn really slowly though, typically small DC motors will slow down to a point and then stall due to friction.