DESIGN: ~ Single-Bladed All Electric Rotor - Flight & Power Control

• Collective: Throttle & Pitch-torque coupling. The throttle increases or decreased in both motors in unison.
• Roll: Throttle & Pitch-torque coupling. The throttle is increased or decreased disproportional between the two motors.
• Pitch: Longitudinal cyclic. Both rotors are pitched forward or backward in unison.
• Yaw: Opposed Longitudinal cyclic. One rotor has its longitudinal pitch increased while the other rotor has its longitudinal pitch decreased.
• Autorotation: Automatic entry due to the pitch-torque coupling.

• The collective and the roll are electrically controlled. Why not make the pitch and yaw electrically controlled also since they only requires one actuator per rotor. In addition, by having the actuator rotate with the rotor and using a commutator to transmit the electricity there is no need for a swash plate.
• If the pitch for cyclic and yaw is controlled electrically at each rotor it then makes sense to determine the torque at each rotor at the controller and actuate the Pitch - Torque coupling electrically.
• This ten means that all flight controls and more can be handled by a side-arm controller (joystick) in the cockpit. Look for the information on the cyclic grip that can be bought.

1. Initially the joystick can be used for control via wired connection
2. Then for wireless control from the ground when craft is an Unmanned Air Vehicle
3. Then the joystick is inserted in the cockpit.

• Refer to the sketch of the blade, which is located a few paragraphs above.
• Consider that; the blade, the arms that go back to the motor, and the motor are all one rigid assembly.
• Consider that this complete assembly can rotate (+ & - 15º) about the pitch axis of the blade.
• This means that the pitch bearings are subjected to very little axial loading, because there are centrifugal forces pulling in both directions.
• Consider that that the motor's torque about the stationary crown gear on the mast, with its downward facing teeth, will want to give the blade a positive pitch.
• This creates the opportunity that this feature might be the foundation of the desired torque-pitch coupling device. In other words, if the motor stops then the blade will automatically pitch down to the autorotation setting. The remaining development is then to have the incremental blade pitch set by the incremental torque of the motor.
• This also creates the opportunity for the motor controller to control ALL of the flight-control actions by the azimuth phase timing the amount of power that is transmitted to the motors in each rotor. In other words, the motor controller sets the collective and the roll by the amount of power that is transmitted to each motor. The motor also controls the craft's pitch and yaw by the cyclical azimuth increases and decreases in the power that it transmitted to each motor.
• Holy shit ~ All electric joystick control.
• This assumes that the additional inertia about the pitch axis, beyond that of the blade, will not be too much to allow 1P cyclic control.
• Alternatively, if the inertia is not a problem, then perhaps 2P cyclic control might be possible.
• This can be tested now with a couple of the existing CNC motors, controllers, encoders and azimuth detector. Start by using the Mach3 CNC program in lieu of the joystick.
• Pitch Torque: See; DESIGN: ~ Single-Bladed All Electric Rotor - Rotor Hub - Pitch-Torque Coupling

• The craft will automatically go into autorotation if the batteries were to loose their charge during flight. This is due to the torque-pitch coupling. Control of the craft during descent should be no problem. The pitch and yaw are handled by the longitudinal cyclic control. Roll is handled electrically by utilizing the two motors as motor-generators and then the pilot determines the direction and amount of electrical flow between the two motors. Collective for flare can be provided for by having a small lightweight capacitor, which provides a short duration of power to both motors.
• Concern: A high gear ratio between the rotor and the motor may not allow the rotor to turn the motor a make it operate as a generator.

• See; DESIGN: ~ Single-Bladed All Electric Rotor - Rotor Hub - Delta3

• See; DESIGN: ~ Single-Bladed All Electric Rotor - Rotor Hub - Pitch-Torque Coupling
• The requirement may exist for having a sensor to input the actual blades pitch in addition to a sensor that is measuring the torque of the powertrain.

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• Tachometer:
• Digital Tachometer:
• Absolute Encoder - Yes
• Resolver:
• Encoder:

• Pilot:
• Cyclic. Need Azimuth and Radial distance
• Collective. Need Distance
• Yaw. Need Direction and Distance
• Ref. See; UniCopter~ Control - Flight - Sidearm Controller
• Longitudinal trim
• Sensors:
• Azimuth of each blade:
• Flap angle of each blade:
• Power consumption rate of each blade.
• Pitch of each blade: There is a clear area between the mast and the rotor&arm assembly to place electronic sensors [input] of the pitch and flap.
• Angle of Attack of each blade: Sensor at blade tip and at root, then interpolate for 0.75 R.
• Forward velocity of craft: Pitot tube.
• Aircraft Angle of Attack: Vane with damper.

• To minimize the drag induced vibration resulting from forward velocity it will probably be necessary to sense:
• The angle of Attack of the blade at 0.75 R.; or
• The pitch of the blade, the aircraft's angle of attack and the azimuth of the blade; or
• The pitch of the blade, the airspeed and the azimuth of the blade.

• Motors:
• Power to each motor.
• Perhaps an electrical actuator will be required to work with the motor torque to set the required angle of attack at specific azimuths to achieve forward flight. Adjustment of the Pitch: An electrical adjustment device [output] can be located here. It might something simple like a couple of opposing solenoids with the amount of adjustment by the duration of electronic pulses.
• Instruments:
• RRPM of each motor (rotor).

• Constantly looping through inputs and outputs ???

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