Item 0812
OTHER:
Helicopter - Inside - Coaxial - Electric Motor Located in Rotors
SloMoCo
(Slow Motor ~ Coaxial Configuration)
This page maybe changed to that of simply mounting a couple of
ELECTROTOR-SloMo Principal assemblies (motor & rotor) together on an small internal frame. ~ January 18, 2010
Objective:
To locate a ELECTROTOR-SloMo Principal assembly in a frame that creates a coaxial arrangement.
Targets:
An extremely high level of reliability. [No breakdowns. No loss of energy (fuel)]
A very fast rate of control.
A principal assembly that has very low-weight.
Drawing:
Overview:
Electrotor ~ SloMo; Axial Flux Permanent Magnet [AFPM] motor. Axial air gap. No. probably going with Transverse Flux ~ September 18, 2009
With parallel (but isolated) wiring double or triple redundancy can be incorporated in the; batteries, power circuit and motor.
Hopefully, [Blade Pitch Control] can also be incorporated.
Direct Control, supplemented by Weight Shift for greater pilot authority. OTHER: Flight Dynamics - Rotor Hub - Offset Bi-teetering
Collective control by hand grip throttle.
Autorotation by automatic entry, with capacitor assisted flare at landing.
Powered by a single electric motor, which has 1:1 rpm relationship and direct coupling to the two counterrotating rotors. ElectrotorSloMo.
- May go with absolutely mechanically separated motors. This will allow the rotor-motor assembly to be used in any small recreational twin-rotor helicopter.
~ September 18, 2009
Drawing:
The current objective is to go with 'absolutely' rigid rotors backpack as above. Not the below.
See 1751.html for the similar idea in Intermeshing configuration.
Reconsider the layout below.
Consider using one spread 45º-delta3 in the center, two 30º-delta2s at there current locations and the CVJw/HS attached to the mast and the motor's stator.
- The decone reduces some cross-couplings. Note the precone should probably not be negative since this might result in the coning angle being negative when operating under loading less than 1G. Have the hub-bar level, which will result in a positive coning angle in autorotation without an undersling but this should be OK for this infrequent event.
- The delta3 aerodynamically forces the tip-path-plane to align with the control-plane.
- The delta2 provide the torque-pitch coupling.
- The single CVJw/HS provides the additional (weight-shift) control power.
Review the cross-couplings of everything.
See Alternatives A & B below re using the preferable two rotors and one stator.
Motor:
See;
DESIGN: Electrotor-SloMo - Motor - Overview - 4-phase for SloMoCo (and Bilateral?)
Power Sources:
One heck of a lot of high performance (yet to be developed) batteries. With today's technology the flight time would be logged in minutes.
Generator driven by small (yet to be developed) turbine.
Ground tether containing electrical cable.
Large lightweight Ultracapacitor(s) for flare at the end of autorotation. Could be charged by rotors during autorotation.
Capacitors are very light weight. In fact, there is consideration for using the honeycomb core in a composite construction fuselage as a capacitor/battery.
Principle Assembly for this craft; Electrotor-SloMo ~ Power Storage Devices
Stability:
Have a large coning angle of 4 to 5 degrees.
- To give static stability in forward flight. I.E. to cause the disk to want to tilt back.
Control:
Consider using patent US 5,043,641. Have hard copy.
See: Electrotor-SloMo ~ Control (flight & power)
Related Pages:
A Related Patent:
- 4,311,080 US ~ Drive mechanism ~ January 19, 1982 ~~ circular linear induction
A Somewhat Similar Method:
An associated Concept - Perhaps:
Control and UAV:
This small (25 employee) Canadian company interesting. http://www.micropilot.com/. There is an article on it in the business section May 30, 2006 Globe and Mail.
Principle Assembly for this craft; Electrotor-SloMo ~ Control (flight & power)
Idea Related to 2-phase:
See patent; US 4,968,913. When looking at drawing number 1; Consider a Rotor-Stator-Rotor arraignment. Leave the stator as is and make the second rotor a mirror image of the first; to get opposite rotation between the two rotors. Got to check the validity of preceeding statement.
I do not think that this will assure synchronized rotation for maintaining fixed blade-crossing azimuths. Perhaps additional electric items might be added.
What would be the best winding configuration for the stator? - Torus ?
What would be used to start both rotors in the correct direction? A 3rd small starting phase? Or, a few nylon pinion gears between the two rotors so that both can be pre-spun in a counterrotating direction by the hand of the pilot turning the lower one only?
Idea Related to 4-phase:
See A131.html
See; Perhaps Relevant Patents
Concerns:
The resistance of the electric motor to turn (cogging) if no power. Overrunning clutches will overcome this potential problem.
The efficiency (power to weight) of the axial-flux motor.
The diamond shape of the hub-bar, combined with centrifugal force, will strongly resist pitch change. Use delta-2?
2P vibration on the absolutely rigid rotor.
Rotor:
Rotorhub:
An idea that is intended to assure that the rotors disks have a small gap while not clashing with each other. OTHER: Miscellaneous - Thoughtless Ideas - Coaxial - Rigid-Teetering Rotors
Blade:
- The blades should be very lightweight and asymmetrical (VR-7).
Control:
Drawing:
Alternative A - Hub-Spring
?:
Alternative B - Bi-teetering:
Alternative C -
Aerodynamically Active Blade Twist:
Workup:
Start with the Schöffman coaxial. Thread on Rotary Wing Forum about Frans Schoeffman's coaxial helicopter.
Add a simple light seat, skids and frame.
Replace the two rotor hub bars with composite one that has a Torque/Pitch Collective Rotor Hub at the root for Collective and Autorotation. See; OTHER: Miscellaneous - Thoughtless Ideas - Torque/Pitch Collective Rotor Hub and Torque-Pitch-RRPM: To give electric auto-collective and cyclic control
Replace the 4 propeller blades with +/- 8 ft very light composite blades.
The control to be by gimbaled head. Except that the lack of a teetering hinge will cause it to be weight-shifting. Except that the below will allow it to be a compromise.
Add a somewhat simplified Independent Root & Tip - Torque Tube Method for Cyclic. The control to be Swishring.
Axial Motor 2 rotors, with Halbach magnet, turning on a central stator. 2-phase. See 1530.html.
Alternative Motor: See OTHER: Miscellaneous - Thoughtless Idea - Engine for Coaxial Rotor
[Source ~ MDD p.20] Discuses Drag and Flapping Pivots
[Source ~ MDD p.122] Figure 12 shows coincidental drag and flapping Pivots.
Related Subjects:
Damper on Rotor Hinges:
Should dampers and/or very strong springs be incorporated into the connecting rods on the bi-teetering rotor heads?
Overhead Control Arm:
Consider making the bar from fiberglass tubing, or other material with elasticity, At a specific frequency, the overhead arm may negate much of the 2P vibration from the rotor during large cyclic positions.
Cyclic Range:
Would a larger range of freely-teetering cyclical movement be better than a shorter range with the control (and associated force and vibration)?
Related Pages:
OTHER: Helicopter - Inside - Bilateral - Electric Motors Located In Rotors ~ SloMoSynchro This represents the opportunity to have a lower disk loading.
OTHER ~ Flight Dynamics - Rotor Hub - Aerodynamically Active Blade Twist
OTHER ~ Flight Dynamics - Rotor Hub - Hub Spring (Hinge Spring)
Schoeffman's Ultralight Helicopter
Alternative Drive:
OTHER: Miscellaneous - Thoughtless Idea - Engine for Coaxial Rotor
Introduction Page | SynchroLite Home Page | Electrotor Home Page | UniCopter Home Page | Nemesis Home Page | AeroVantage Home Page:
Initially displayed: April 21 2003 ~ Posted on PPRuNe: May 15, 2004 ~ Last Revised: January 18, 2010
The above utility invention is openly and publicly disclosed on the Internet to negate an entity from patenting it, to the exclusion of all others whom may wish to use it. ~ Reference patent law 35 U.S.C. 102 A person shall be entitled to a patent unless - (a) the invention was known ... by others in this country, ..., before the invention thereof by the applicant for patent.