The invention discloses an active vibration or sound absorption method with virtual resonators exclusively using sensing electromagnetic coil's current and voltage. The invention includes an absorption actuator, a sensing module of coil's current and voltage, an absorption controller, and a driving module. The method controls the coil current's phase to be orthogonal to the actuator velocity's phase, to adjust the resonant frequency of the actuator, such that the signal to be absorbed causes a resonance in the actuator. In this way, a virtual resonator is formed. Moreover, one actuator can generate multiple virtual resonators simultaneously to absorb energy of multiple signals with different frequencies, and the resonant frequency and its damping ratio for each virtual resonator can be adjusted independently.

A suspension system (22) configured to minimize transmission of acoustic and vibrational energy in a device, comprising: (i) a rigid support (24); (ii) an operative element (16) positioned within the rigid support and comprising a drive frequency when the device is in operation; and (iii) a resilient element (26) engaging the rigid support and configured to create a resilient force against one or more degrees of freedom of vibrations generated by the operative element; wherein the natural frequency in one or more of the degrees of freedom of the suspension system, in the degrees of freedom of interest, are tuned into a narrow resonant frequency range by the suspension, and wherein the resonant frequency is less than the drive frequency.

The present disclosure relates to a matrix electromagnetic-suspension system attachable to transportation vehicles. The system comprises a plurality of electromagnetic-suspension modules, each module comprises: an armature; a coil wound on the armature; an adjustable power source connected to the coil, configured to control the intensity of a first magnetic field; and two permanent magnets disposed in contact with the armature, by means of opposite poles, which generate a second magnetic field. The plurality of modules are disposed in a matrix which ensures that the adjacent poles of the permanent magnets of adjacent modules have the same polarity.

There is provided a vibration suppression device of a rope-like body that can use a negative restoring force that amplifies a displacement of a rope-like body of an elevator to prevent the displacement from becoming unstable. A vibration suppression device (21) includes a first displacement measurement unit, a first displacement amplifier, and a control unit (24). The first displacement measurement unit measures a displacement in a lateral direction of the rope-like body due to vibration about an equilibrium position (20) at a first position (P1) in a longitudinal direction of the rope-like body. The first displacement amplifier applies, to the rope-like body, a negative restoring force that amplifies the displacement of the rope-like body. The control unit (24) causes the first displacement amplifier to apply a negative restoring force smaller than a positive restoring force, based on the displacement measured by the first displacement measurement unit.

A body weight adjustment mechanism for automatic adjustment to a balanced point is provided to improve vibration absorption characteristics and impact absorption characteristics. A torsion angle of a lower frame-side torsion bar when an upper frame is at a balanced point is found in advance, a torsion angle of the lower frame-side torsion bar in a state in which a person is seated is detected, the detected torsion angle is compared with the aforesaid balanced point torsion angle, a control signal is sent to an elastic force adjusting unit, and torsion angles of upper frame-side torsion bars are adjusted so that the torsion angle of the lower frame-side torsion bar becomes equal to the balanced point torsion angle. The upper frame can be set to an appropriate position in an initial state and a static state in which a person is seated and vibration and impact absorption characteristics are improved.

A body weight adjustment mechanism for automatic adjustment to a balanced point is provided to improve vibration absorption characteristics and impact absorption characteristics. A torsion angle of a lower frame-side torsion bar when an upper frame is at a balanced point is found in advance, a torsion angle of the lower frame-side torsion bar in a state in which a person is seated is detected, the detected torsion angle is compared with the aforesaid balanced point torsion angle, a control signal is sent to an elastic force adjusting unit, and torsion angles of upper frame-side torsion bars are adjusted so that the torsion angle of the lower frame-side torsion bar becomes equal to the balanced point torsion angle. The upper frame can be set to an appropriate position in an initial state and a static state in which a person is seated and vibration and impact absorption characteristics are improved.

A system (1) for vibration management comprises a stator (24, 45); a rotor (26) being mounted rotatably with respect to the stator (24, 45) about a rotational axis (9); one or more active devices (41A-41C) adapted to apply forces and/or moments on the rotor (26) and/or on the stator (24, 45); at least two sensors (42) for measuring vibrational parameter values with respect to two or more different positions, particularly along the rotational axis (9); and a controller (44) adapted to provide control signals to the one or more active devices (41A-41C) based on the vibrational parameter values of the at least two sensors (42) and on the respective position.

A spring system that includes an adjustable spring system that is operated by a motor.

A spring system that includes an adjustable spring system that is operated by a motor.

A workpiece conveyance device includes a base body disposed adjacent to a press machine, a pair of first arms, a pair of second arms, and a first holding portion and a second holding portion independent of each other. Each of the first holding portion and the second holding portion includes a plurality of holding members configured to hold a workpiece W. The first holding portion includes a first support member, a second support member, and an absorption member. The second support member movably supports the first support member along an intersection direction. The absorption member allows movement of the second support member caused in the intersection direction relative to the first support member, and makes it possible for the second support member to return to an initial position in the intersection direction relative to the first support member.