A suspension device includes: a hydraulic damper including a rod provided with a valve for generating a hydraulic pressure when the rod is displaced between a first liquid chamber and a second liquid chamber; an electric damper configured to electrically displace the rod by an actuator; and a communication passage that establishes communication between the first liquid chamber and the second liquid chamber while bypassing the valve during operation of the electric damper.

A suspension device includes: a hydraulic damper including a rod provided with a valve for generating a hydraulic pressure when the rod is displaced between a first liquid chamber and a second liquid chamber; an electric damper configured to electrically displace the rod by an actuator; and a communication passage that establishes communication between the first liquid chamber and the second liquid chamber while bypassing the valve during operation of the electric damper.

A magnetic liquid damping shock absorber includes a housing, a thermal insulating material layer, a mass block and a magnetic liquid. The housing defines a sealed cavity, the sealed cavity has a first wall face and a second wall face opposite in a first direction and a circumferential wall face located between the first wall face and the second wall face in the first direction. The thermal insulating material layer is provided on an outer surface of the housing, on a wall face of the sealed cavity or in a housing wall of the housing. The mass block is located in the sealed cavity, and the mass block and the housing define a magnetic liquid cavity therebetween. The magnetic liquid is filled in the magnetic liquid cavity.

A magnetic fluid damper includes a housing defining a cavity; a plurality of mass blocks located in the cavity and spaced from each other in a first direction; at least one energy dissipating assembly, in which the plurality of mass blocks and the at least one energy dissipating assembly are arranged alternately along the first direction in the cavity, in which each energy dissipating assembly includes a first permanent magnet and a first porous medium member, pores of each first porous medium member being filled with first magnetic fluid; and a plurality of reset parts cooperating with the plurality of mass blocks in one-to-one correspondence to apply restoring forces in a second direction to the mass blocks, in which restoring forces received by two mass blocks adjacent in the first direction are not equal.

A magnetic fluid damper includes a housing defining a cavity; a plurality of mass blocks located in the cavity and spaced from each other in a first direction; at least one energy dissipating assembly, in which the plurality of mass blocks and the at least one energy dissipating assembly are arranged alternately along the first direction in the cavity, in which each energy dissipating assembly includes a first permanent magnet and a first porous medium member, pores of each first porous medium member being filled with first magnetic fluid; and a plurality of reset parts cooperating with the plurality of mass blocks in one-to-one correspondence to apply restoring forces in a second direction to the mass blocks, in which restoring forces received by two mass blocks adjacent in the first direction are not equal.

A second electric suspension device includes a second electromagnetic actuator that is provided between the vehicle body and a wheel of a vehicle and generates a driving force for damping vibration of the vehicle. The second electromagnetic actuator includes a columnar rod member and a casing surrounding the rod member and being provided capable of moving forward and backward relative to the rod member in the axial direction. Casing-side armature coils are provided in the casing in the axial direction, whereas magnets are provided in the rod member in the axial direction in such a manner as to face part of the casing-side armature coils in the casing. The magnets are formed by permanent magnets and electromagnets including rod-side armature coils.

An eddy current damper includes a magnet holding member, a first permanent magnet having a thickness (H1), a second permanent magnet having a thickness (H1), a conductive member, a ball nut, a screw shaft, and a copper layer having a thickness (H2). The second permanent magnet is adjacent to the first permanent magnets with a gap therebetween in the circumferential direction of the magnet holding member. The ball nut is fixed to the magnet holding member or the conductive member. The copper layer is fixed to the conductive member and is opposed to the first permanent magnet and the second permanent magnet with a gap therebetween. The thickness (H1) and the thickness (H2) satisfy, with respect to a distance (R1) between a central axis of the screw shaft and the center of gravity of the first permanent magnet:

0.018≤H1/R1≤0.060, and

0.0013≤H2/R1≤0.0065.

A multi-dimensional magnetic negative-stiffness mechanism and a multi-dimensional magnetic negative-stiffness vibration isolation system composed thereof are provided. The multi-dimensional damping system is composed of a positive-stiffness mechanism, a multi-dimensional negative-stiffness mechanism, a floating frame, a vibration isolated body, and a mounting base. The positive-stiffness mechanism is a traditional elastic element connected to the vibration isolated body and the mounting base, and provides supporting forces in an X direction, a Y direction, and a Z direction, and a basic vibration isolation function. The multi-dimensional negative-stiffness mechanism is composed of at least two negative-stiffness magnetic groups. Each negative-stiffness magnetic group may provide one-dimensional or two-dimensional negative stiffness. Through a series connection of the at least two negative-stiffness magnetic groups, a two-dimensional or three-dimensional negative-stiffness effect may be implemented to improve the vibration isolation performance of the system in multiple dimensions.

An outdoor robotic tool (10) comprising a first part (20) and a second part (30), wherein the first part (20) supports the second part (30) through a suspension arrangement. The suspension arrangement comprises a first component (40), which comprises at least one magnetic member; and a second component (50), which comprises at least one magnetic member. The first component (40) is attached to the first part (20), wherein the second component (50) is attached to the second part (30), wherein at least one of the magnetic members of suspension arrangement is a permanent magnet (42, 52); and wherein a magnetic member of the first component (40) is positioned so as to magnetically interact with a magnetic member of the second component (50) when in use. A magnetic field sensing unit (60) may be present that comprises a control unit (61) and a magnetic field sensor. A method for detecting the alignment of the first part (20) relative to the second part (30), wherein the method comprises detecting the magnetic field using the magnetic field sensing unit (60), is also disclosed.

The present disclosure discloses an electromagnetic multistage adjustable variable inertance and variable damping device. Iron cores are magnetized by winding electromagnetic coil windings outside the iron cores and applying an electric current action to the electromagnetic coil windings, and air gap magnetic fields are generated by the magnetized iron cores and permanent magnets in air gaps to cause the variation of shear damping forces between a driving shear plate and magnet yokes and between driven shear plates and magnet yokes, which avoids that the mechanical properties of an inerter cannot be fully utilized due to the friction caused by mutual contact among parts, thereby realizing multistage real-time adjustability of an instance coefficient and a damping coefficient of the device.