One embodiment is an electric drive system including a plurality of redundant motors, wherein power generated by the plurality of motors is used to drive a rotor system comprising a rotor shaft having a plurality of rotor blades connected thereto via a swashplate; a gear box associated with the plurality of redundant motors; a cyclic actuation system for controlling an individual pitch of the rotor blades connected to the swashplate; and at least one structural element for retaining the redundant motors, the gear box, and the cyclic actuation system together as a single integrated unit.

An adjustable control link for transferring rotor shaft rotation to a rotating swashplate, the adjustable control link includes an elongate element rotatable with the rotor shaft, the elongate element having a first end. A structure has an opening and a second end. At least one cam component is disposed within the opening and is rotatable relative to the structure about a central axis of the opening. A pin is configured to couple the elongate element to the at least one cam component. The pin is eccentrically rotatable about the central axis to move the first end of the elongate element relative to the second end of the structure.

An adjustable control link for transferring rotor shaft rotation to a rotating swashplate, the adjustable control link includes an elongate element rotatable with the rotor shaft, the elongate element having a first end. A structure has an opening and a second end. At least one cam component is disposed within the opening and is rotatable relative to the structure about a central axis of the opening. A pin is configured to couple the elongate element to the at least one cam component. The pin is eccentrically rotatable about the central axis to move the first end of the elongate element relative to the second end of the structure.

In one aspect, the present disclosure provides a system for reducing vibrations or stresses in a rotor blade system. The system may include at least three rotor blades configured to be rotated about a main rotor axis, where each of the three rotor blades may be adjusted by at least one electrically-adjustable control rod of a plurality of control rods. The plurality of control rods may include a first number of control rods forming a first group, and the plurality of control rods may include a second number of control rods forming a second group. A first circuit for may activate or deactivate the first group of control rods, and a second circuit may activate or deactivate the second group of control rods.

In one aspect, the present disclosure provides a system for reducing vibrations or stresses in a rotor blade system. The system may include at least three rotor blades configured to be rotated about a main rotor axis, where each of the three rotor blades may be adjusted by at least one electrically-adjustable control rod of a plurality of control rods. The plurality of control rods may include a first number of control rods forming a first group, and the plurality of control rods may include a second number of control rods forming a second group. A first circuit for may activate or deactivate the first group of control rods, and a second circuit may activate or deactivate the second group of control rods.

A compound aircraft includes a convertible thruster that pivots between an anti-torque position, a forward thrust position, and intermediate positions. A pilot has two inceptors to control thruster rotor pitch in the anti-torque and forward thrust positions. A mixer mechanically blends the signals from the two inceptors during transition between the anti-torque and forward thrust positions. A transfer rod coaxial with the pivot axis of the convertible thruster conveys convertible thruster pitch commands from the pilot to a pitch control actuator. The pitch control actuator may be located partially within the rotor of an electric motor that rotates the convertible thruster rotor. The electric motor and pitch control actuator are unitary. Both the electric motor and pitch control actuator pivot with the convertible thruster. The pitch actuator output shaft is coaxial to and disposed within a hollow electric motor output shaft.

Embodiments are directed to systems and methods for estimating wear in aircraft rotor systems. Data associated with loads and motions of a swashplate actuator is collected. The swashplate actuator drives a swashplate and at least one control link is coupled to the swashplate. The loads and motions of the at least one control link is estimated based upon the loads and motions of the swashplate actuator. Using a wear model, the current wear of control link components is estimated due to the loads and motions of the at least one control link. Wear estimates for the components are aggregated across multiple flights and used to determine when maintenance actions should occur.

Embodiments are directed to systems and methods for estimating wear in aircraft rotor systems. Data associated with loads and motions of a swashplate actuator is collected. The swashplate actuator drives a swashplate and at least one control link is coupled to the swashplate. The loads and motions of the at least one control link is estimated based upon the loads and motions of the swashplate actuator. Using a wear model, the current wear of control link components is estimated due to the loads and motions of the at least one control link. Wear estimates for the components are aggregated across multiple flights and used to determine when maintenance actions should occur.

A control system for a multi-rotor aircraft is described that results in lower operating noise. Allowing blades to flap during flight reduces aerodynamic interference as blades pass by other aircraft components, such as wings or the fuselage. Pitch links coupled to a rotational swashplate can be used to allow flapping during flight. The swashplates can allow the canting of the rotors to change a rotational or out-of-plane angle of the blades to decrease noise.

A control system for a multi-rotor aircraft is described that results in lower operating noise. Allowing blades to flap during flight reduces aerodynamic interference as blades pass by other aircraft components, such as wings or the fuselage. Pitch links coupled to a rotational swashplate can be used to allow flapping during flight. The swashplates can allow the canting of the rotors to change a rotational or out-of-plane angle of the blades to decrease noise.