A motor control device of a vehicle including an engine and a motor generator, a transmission transmitting an engine torque and/or a motor torque to a wheel, and a damper reducing vibration of a crankshaft of the engine includes: a damper torque calculation unit calculating a damper torque generated by the damper according to fluctuation in engine torque based on a difference between a crank angle and a motor angle; a reverse-phase torque calculation unit calculating a reverse-phase torque with a reverse phase to the damper torque; a correction amount calculation unit calculating a first value calculated at least based on the crank angle and the motor angle; and a motor torque command output unit outputting a motor torque command given to the motor generator based on the reverse-phase torque corrected by the correction amount.

Systems, devices, and methods for a hub-based active vibration control (AVC) design includes at least one pair of co-rotating motorized imbalanced rotors that create a controllable rotating force vector that can be controlled to cancel hub loads on a rotating hub. This control is achievable using a configuration in which each rotor has an axis of rotation that is offset from the hub axis of rotation. In this way, in a loss of operation failure mode, the system is designed such that centrifugal forces will cause the masses to spin to an orientation of low static imbalance.

A vibration attenuation system for attenuating vibrations in a mast of an aircraft includes a weight attached to the mast but free to orbit about the mast. The weight can be comprised of one or more weight assemblies. Embodiments can include a single weight, or plural weight assemblies wherein each weight assembly can include a mechanical interconnecting mechanism so that each weight assembly receives feedback regarding the position and movement of one or more other weight assemblies. Each weight can be associated with a spring that urges the weight towards a neutral position. Rotation of the mast can cause the weight to orbit about the mast and self-excite such that the weight acts against the urging of the spring towards an attenuating position.

A vibration control assembly includes a housing having an interior region and an inner mass including a cage disposed within the interior region of the housing and being rotatable within the housing about a first axis and a gyroscope wheel disposed within the cage and rotatable about a second axis other than the first axis. At least one driving source includes a stator and is operable to interact with a magnetic field of the inner mass to drive rotation of the inner mass about at least one of the first axis and the second axis, wherein the at least one driving source is mounted within the interior region of the housing.

A vibration reduction device (5) including: a counterweight (6) provided to a crankshaft (14) of a Stirling engine (1); and an electric balancer (7) being attached to a crankcase (15) and including a balance weight (73) rotated by an electric motor (74). An inertial force of the counterweight (6) is set to approximately a half of a combined inertial force of pistons (12, 13). Inertial force of balance weightL2=combined inertial force of pistonsL1 is satisfied when a mass of the balance weight is set, where L1 denotes a distance between a vibration reduction target position and a rotation center (O1) of the crankshaft (14), and L2 denotes a distance between the vibration reduction target position and a rotation center (O2) of the balance weight (73).

A vibratory compactor includes a drum, a frame supporting the drum, an eccentric shaft configured to be rotated by a vibration motor, and a primary eccentric weight attached to the eccentric shaft inside the drum. At least one active isolation eccentric weight is located outside the drum so that when the eccentric shaft is rotated, a phase of a vibration generated by the at least one active isolation eccentric weight is substantially opposite to that of a vibration generated by the primary eccentric weight.

A balance assembly for an engine is provided. The balance assembly includes a first electric motor coupled to the engine and configured to rotate a first eccentric mass relative to the engine, the first eccentric mass being coupled to a first shaft of the first electric motor, and a second electric motor coupled to the engine and configured to rotate a second eccentric mass relative to the engine, the second eccentric mass being coupled to a second shaft of the second electric motor. The first and second electric motors are configured to rotate the first and second eccentric masses in order to balance a vibration characteristic of the engine.

Provided is a dynamic force generator having a supporting shaft, a first rotor including an internal bore housing the supporting shaft and bearings arranged between the supporting shaft and the internal bore so that the first rotor is mounted rotatably in relation to the supporting shaft, an external bore having an inner face provided with a first set of permanent magnets. A first unbalanced mass is within the internal bore of the first rotor and mounted opposite an outer face of the external bore of the first rotor. A second rotor is mounted rotatably in relation to the first rotor, via an antifriction component provided between the first rotor and the second rotor, and includes an internal bore housing the internal bore of the first rotor so that the internal bores of the first and second rotors are concentric, and an external bore with a second set of permanent magnets.

The disclosure is directed at a method and apparatus for controlling unwanted vibrations in a mechanical system. The apparatus includes a set of different eccentric and/or concentric masses mounted to the mechanical system for generating forces to counteract the sensed unwanted vibrations. The apparatus further includes a set of motors that control movement of the set of masses.

A vibratory compactor is described that includes a drum, a frame supporting the drum, an eccentric shaft configured to be rotated by a vibration motor, and a primary eccentric weight attached to the eccentric shaft inside the drum. At least one active isolation eccentric weight is located outside the drum so that when the eccentric shaft is rotated, a phase of a vibration generated by the at least one active isolation eccentric weight is substantially opposite to that of a vibration generated by the primary eccentric weight.