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Re: drones

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On 12/08/2015 06:48 PM, jimp@specsol.spam.sux.com wrote:
> benj <none@gmail.com> wrote:
>> On 12/08/2015 05:02 PM, jimp@specsol.spam.sux.com wrote:
>>> RichD <r_delaney2001@yahoo.com> wrote:
>>>> I notice, with these new toy drones, they all use quad rotor
>>>> design.  Why?
>>>>
>>>> I never studied aerodynamics, but I'm willing to learn -
>>>>
>>>> -- Rich
>>>
>>> Getting stability is simpler, i.e. it doesn't require
>>> trigometric calculations that 3 rotors would.
>>>
>>
>> It's simple math called a "series". One rotor doesn't work. two is
>> better, three is better still, four is even better and eight is
>> best of all!
>
> One rotor works; you just need power and tilt control for the rotor
> and something like  a tail rotor to counter main rotor torque.

Um, have you been taking lessons from Glazier again?  In my math book a 
lifting rotor and a tail rotor adds up to... er... wait for it... two 
rotors! :-)

> Two rotors in tandem solve the torque problem but get mechanically
> complex.

Yeah, a friend of mine has a toy copter with counter rotating (two) 
rotors. Works. But as far as I can tell you have to be 6 years old or 
younger to actually fly it without crashing.

> Two rotors in line also solve the torque problem but this also gets
> mechanically complex needing full tilt control for both rotors.

Yes.

> Three rotors require trigonometric calculations for rotor control.

Um, have you noticed that 32 bit computers the size of postage stamps 
are available for a couple of bucks these days. Even scarier is they all 
seem to come from China. For about $20 you can get a control for any 
number of rotors. All math done for you. You've been working with the 
military pricing schedule for too long.

> Four rotors is simplest of all, only reqiring rotor power control.

Yeah, my friend has one of those too! Doesn't have the GPS or barometric 
stabilizer, but while easier than the two rotor job to fly it still 
takes a bit of skill!

> Anything above four starts complicating calculations for rotor
> control.

I think the $20 controller does up to 8 rotors.

>> "Professor" Sam Wormley will now explain the physics of why this is
>> true.
>
> A paper airplane designed by the above would likely explode...
>
>> Math "explains" everything in the universe!
>
>
>


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drones RichD <r_delaney2001@yahoo.com> - 2015-12-08 13:29 -0800
  Re: drones Poutnik <poutnik4nntp@gmail.com> - 2015-12-08 22:56 +0100
    Re: drones jimp@specsol.spam.sux.com - 2015-12-08 22:16 +0000
  Re: drones Mahipal <mahipal7638@gmail.com> - 2015-12-08 14:02 -0800
  Re: drones jimp@specsol.spam.sux.com - 2015-12-08 22:02 +0000
    Re: drones benj <none@gmail.com> - 2015-12-08 17:49 -0500
      Re: drones jimp@specsol.spam.sux.com - 2015-12-08 23:48 +0000
        Re: drones benj <none@gmail.com> - 2015-12-08 23:08 -0500
          Re: drones jimp@specsol.spam.sux.com - 2015-12-09 06:16 +0000
  Re: drones Sam Wormley <swormley1@gmail.com> - 2015-12-08 21:44 -0600
    Re: drones benj <none@gmail.com> - 2015-12-08 23:22 -0500

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