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Old Mar 12, 2013, 01:09 PM
Mosquito 6
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Originally Posted by rimshotcopter View Post
I precisely drilled a toy gyro and attacked it to the shaft of the motors as shown in the picture below. As for the Variable pitch system, I would used two 450 Helicopter rotors rigged for Pitch only (KIS).

Ahhh .. I see now .. a picture's worth a thousand words. And the pellets are for balancing? LOL .. The only ammo still available .. almost. Your dish experiment .. was to increase rotational inertia? Or pehaps like the crank damper on an IC engine? Never seen that before .. just curious.

Yeah, the stock heli parts are reasonable and available, but I'm just a spectator on this thread .. I got my hands full with the sedecopter (wasp whacker) and an octo coming up with the MT4008's .. sweet

Cheers ..
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Old Mar 12, 2013, 01:17 PM
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Gyroscopic Force Experiment

Here is a simple experiment that can be easily constructed from an old LP record, burshless motor and prop adapter. Spin up the LP using a string and move the motor forward and aft. Note the direction of the force.

Gyroscopic Force Experiment (0 min 53 sec)
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Old Mar 12, 2013, 01:23 PM
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Originally Posted by TayNinh68 View Post
Ahhh .. I see now .. a picture's worth a thousand words. And the pellets are for balancing? LOL .. The only ammo still available .. almost. Your dish experiment .. was to increase rotational inertia? Or pehaps like the crank damper on an IC engine? Never seen that before .. just curious.

Yeah, the stock heli parts are reasonable and available, but I'm just a spectator on this thread .. I got my hands full with the sedecopter (wasp whacker) and an octo coming up with the MT4008's .. sweet

Cheers ..
Let me see if I can put this in its proper context, on an OAT bicopter, PART of the Pitch control is derived from the gyroscopic forces of the spinning props HOWEVER, the ROLL is controlled by thrust differential when using conventional airplane props. This I STRONGLY believe have an advert effect on the Pitch control. This is why I believe, in order for total control of the Pitch axis, will require the employment of a constant rotor rotational speed and a variable the Pitch of the of the Props to control the Roll axis.
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Last edited by rimshotcopter; Mar 12, 2013 at 01:34 PM.
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Old Mar 12, 2013, 01:39 PM
CSU Chico, Flight Club
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Originally Posted by rimshotcopter View Post
... on an OAT bicopter, PART of the Pitch control is derived from the gyroscopic forces of the spinning props HOWEVER, the ROLL is controlled by thrust differential when using conventional airplane props. This I STRONGLY believe have an advert effect on the Pitch control....

so the PID values for roll must also influence the pitch behavior !?
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Old Mar 12, 2013, 01:40 PM
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Originally Posted by Test Pilot Mafia View Post
so the PID values for roll must also influence the pitch behavior !?
I believe you are mixing Apples and Oranges. The electronics have nothing to do with this aspect of the build. If the Airframe is not right, no amount of electronics will make it fly.
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Old Mar 12, 2013, 01:50 PM
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Originally Posted by rimshotcopter View Post
I believe you are mixing Apples and Oranges. ...If the Airframe is not right, no amount of electronics will make it fly.
yes, i realize this point. But apparently i dont know how to build a useful airframe.

Even this one wont fly right:
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Old Mar 12, 2013, 01:52 PM
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Originally Posted by Test Pilot Mafia View Post
yes, i realize this point. But apparently i dont know how to build a useful airframe.

Even this one wont fly right:
Well, don't take this harshly but I told you from the onset, your tilting direction was wrong. Honestly, I don't understand how you did this complete rebuild and made the same mistake.
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Old Mar 12, 2013, 01:57 PM
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Originally Posted by rimshotcopter View Post
Well, don't take this harshly but I told you from the onset, your tilting direction was wrong. Honestly, I don't understand how you did this complete rebuild and made the same mistake.
but how is it wrong? i specifically made sure i made the CG/CL and tilting like your proven machines...
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Old Mar 12, 2013, 01:58 PM
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but how is it wrong? i specifically made sure i made the CG/CL and tilting like your proven machines...
Ok Sir.
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Old Mar 12, 2013, 02:17 PM
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RimShot, did you use D value in the pitch axis of your flymentor machine?
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Old Mar 17, 2013, 01:00 PM
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I was very nervous during this test flight for many reasons however, I think this test went well. She is still a little tail heavy but that is easily adjustable by moving the battery forward. I can also modify the weight sifting logic in the firmware to allow adjustment from the transmitter however, I want to keep it centered to allow maximum travel forward and aft during development. Thank you Bob for finding such a wonderful testing location.

Mollie-VTOL at Dominguez Hills (3 min 5 sec)
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Old Mar 18, 2013, 07:10 AM
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It's looking good and stable Richard!
Cheers,
JIm
Quadrocopter and Tricopter Info Mega Link Index
Quote:
Originally Posted by rimshotcopter View Post
I was very nervous during this test flight for many reasons however, I think this test went well. She is still a little tail heavy but that is easily adjustable by moving the battery forward. I can also modify the weight sifting logic in the firmware to allow adjustment from the transmitter however, I want to keep it centered to allow maximum travel forward and aft during development. Thank you Bob for finding such a wonderful testing location.

http://youtu.be/ss1_VRE3pnY
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Old Mar 18, 2013, 07:24 AM
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It's looking good and stable Richard!
Cheers,
JIm
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Thank you Jim, you of all people know of the Journey it took to get here and I really appreciate your support.
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Old Mar 18, 2013, 02:05 PM
which way is up?
Joined Jan 2012
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Another fun idea to needlessly complicate things:
http://www.faqs.org/patents/app/20110147533

Morphing duct geometry to help with forward/windy flight.
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Old Mar 18, 2013, 03:45 PM
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I wonder if Nitinol memory wire could be used for the morphing duct, as seen here...
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