Driven Principal Assemblies, where a hub-motor is an integral part
of the rotorhead.
Primarily for bilateral, quad and
.. Electrotor - SloMo;
- A very rigid rotor assembly that incorporates a slow
speed electric motor in its hub. The 1:1 ratio eliminates the need for a
reducer and other moving components.
- Plus; (Electrotor - Gyro;)
- Incorporates a 2-blade teetering rotor where there
is enhanced flight control due to aerodynamic precession from a rotor,
which has hub springs, plus, gyroscopic precession from a high-speed
Less Viable Projects
.. Electrotor - Simplex;
- A simple arrangement, for development purposes, with
.. Electrotor - MicroLite;
- A simple arrangement, for development purposes, with
'Absolutely' Rigid Rotors.
...,..Electrotor - BladeMotor;
- Each blade has its own motor that sets pitch and
contributes to rotor rotation.
- A rotor with just one blade.
- A very,
very light personal VTOL.
easy to pilot.
of Progressively Attempting to Achieve the Above Objectives:
rotorhead and weight-shift cyclic control.
- Greater precone angle than the conventional. To give greater speed stability in light of the
parasitic drag of the pilot.
- Slow speed
electric motor; thereby eliminating the requirement for a mechanical speed reduction device.
- Low inertial rotor blades; for ease of controllability
and quick rotor rpm change.
- Two-position collective pitch control by, torque/pitch
coupling, lag/pitch coupling, or by piezoelectric pitch control.
- Increasing the diameter of the two rotors w/o
significantly increasing the pilot's physical effort.
- Experimentation with Coaxial, Intermeshing,
Interleaving and Side-by-side configurations.
- Auto-collective, by torque/pitch
coupling, or by piezoelectric pitch
- Multiple independent power and control circuits, for
power transmission reliability; by multi-phase.
- Assured power at landing and takeoff; by having
short-term power storage, such as ultra-capacitors.
- Elimination of autorotation. See; Rotary Wing
thread; The Demise of Autorotation
- Further increasing the rotor diameters, perhaps with Aerodynamically Active Blade Twist, or by electric flight control.
- Electrical braking of rotors after landing; (perhaps).
- Electrical regeneration during descent from high
- Enhanced tip clearance for Intermeshing
(perhaps). To give greater speed stability in light of the parasitic drag
of the pilot.
to be Answered:
- Which is the best
configuration for; flying, plus transportation and storage.
- How best to implement the roll assist mechanism (for
Side-by-side and perhaps interleaving configurations.)
- Design and construction of optimal blade, (Optimal may
differ for different configurations).
- Torque-Pitch coupling (2-position and actively
- Active tip control.
- How large can the blade span become before it is too
difficult to pilot.
- Consider 3-blade rotors with slow speed and wide chord.
To reduce required power, reduce pulsation, and distribute the moments
more equitably around the rotor's bearing and motor's circumference.
- The SloMo.
- The basic MicroLite
- To develop and test larger rotor blades; with
torque-pitch coupling (for collective) and then active tip control (for
cyclic control assist).
- To migrate the electrics up to larger advanced VTOL
craft. (perhaps the AeroVantage and/or
Increasing Safety through Deconstruction
Starting small, then grow
helicopters are cute, they are funny and they are dangerous.
following is a serious look at the Backpack helicopter from an unusual
backpack helicopter that incorporates; a coaxial configuration, short span
blades, collective by rotor rpm, and cyclic by weight shifting, is probably the
most economical helicopter that can be built and the easiest helicopter to fly.
critics are rightly concerned that it will be a very unsafe craft due to; the
lack of speed stability in forward flight,
the inability to autorotate, and the risk of stumbling during a stand-up
conventional solution to overcome these shortcomings would be to upgrade the
wish-list by adding; landing gear, then longer blades, then a collective, then
a teetering hinge, and finally a bigger engine and transmission to lift this
heavier craft. By this point the craft is much more expensive to build and
somewhat more difficult to fly. In addition, all these upgrades add their own
an alternative, consider the possibility of taking a VERY DIFFERENT APPROACH. An approach that might be called 'deconstruction'.
the possibility of producing a safer backpack helicopter by reducing its
complexities and thereby increasing its reliability:
- Replacing the dozens of wearing engine and
transmission parts with a brushless electric motor whose
only wearing parts are it's two bearings.
- Divide the controller's power circuit, the motor's coils,
and the battery packs into two or more totally independent circuits.
- Incorporate redundancy and polling into the control
- The rotor blades are extremely rigid and there are no
- Give the blades (propellers) a 2-position pitch
- Locate the batteries below the torso of the pilot.
- Discharging the weighty primary batteries in a worst
- Provide the pilot with undeniable knowledge of low
battery power, plus a controlled reduction in the available power to the
Elaboration on the above numbered points.
Should a power circuit fail, the motor will still operate, but at reduced power.[/SIZE]
In addition, this simple craft requires very few pilot actuated controls.
To give speed stability during forward flight.[/SIZE]
A torque-pitch capability so that the rotor can provide thrust and accommodate
autorotation. Disk loading would only be 3-1/5 lb/ft.
on a 10 ft dia. [/SIZE]
The lower location of the batteries will assist with weight shifting and reduce
the weight of the motor-rotor assembly[/SIZE]
A lowering or dropping of the batteries will significantly lighten the
remaining weight and significantly assist with a controlled landing. Dropped
batteries could have their own small parachute incorporated into the battery
An ultra-capacitor might be incorporated to provide power during the landing if
the battery pack unit has been released. [/SIZE]
The 'objective' being; absolute
reliability, assured power for touchdown, and easy piloting.
Related Pages - This Site:
Sikorsky Attempting to Inhibit Others from Developing Electric Rotorcraft?
Patent Application US
20090140095 ~ ELECTRIC POWERED ROTARY-WING AIRCRAFT
- This Patent Application makes claims on features such
- The rotor system and the electric motor mounted on
the same axis of rotation.
- The electric motor mounted at least partially within
the rotor hub.
- The use of a slow speed (such as axial-flux -
pancake) motor to eliminate the need for a gearbox.
- All of the above features were previously incorporated
in one or more of the above Electrotors.
- Also, the primary Electrotor inventions above were;
published on the Internet and posted to four different forums, even the
Domain name [Electrotor.com] was acquired, before all of the US
20090140095 dates. ~ The
Provisional Patent Application was filed on Nov. 30,2007.
The Patent Application was filed on January 23, 2008. The Patent
Application was published on on June 4, 2009.
- In addition, all of the claims in the patent
application are commonly known attributes that any rotorcraft and/or
electrical savvy person would know.
- The above Electrotor motor driven rotorcraft concepts
(un-patented inventions) are in the public domain for the use of any and
all who wish to participate in the research and development of
electrically driven rotorcraft?
- For additional information see;
To do a
search on this web side;
- Go to Google.
- Go to 'Advanced Search'.
- Enter the search criteria in the upper boxes.
- Enter 'unicopter.com' in the bottom box.
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Last Revised: 14 March 2013