The present invention discloses a quasi-zero-stiffness (QZS) based six-degree-of-freedom (6-DOF) absolute displacement and attitude measurement device. A lower end coil and an upper end coil are respectively charged with currents in the opposite directions; The electromagnetic field and the magnetic fields of an upper magnet and a lower magnet per se are mutually acted to produce an electromagnetic stiffness opposite to the stiffness of a spring. The stiffness of the whole leg is close to zero stiffness. When the to-be-measured platform generates space motion, the reference platform is in the stationary state. At this point, the deformation amounts of the six legs can be measured by laser displacement sensors. The six deformation amounts are respectively inputted into the displacement and attitude resolver, and by forward kinematic solution of the 6-DOF device, the displacement and the attitude of the to-be-measured platform can be obtained.

A first shock isolator is provided that includes an axial compression element, a first disc spring, a disc spring system, and an annular stand-off. The first disc spring has a non-linear load-deflection response. The disc spring system is configured to be deflected by the first disc spring and has a linear load-deflection response. A second shock isolator is provided that includes an axial compression element, first and second disc springs and corresponding first and second annular stand-offs. The first and second disc springs have non-linear load-deflection responses. The first and second annular stand-offs hold the first disc and second disc springs in a spaced apart parallel configuration. The second disc spring is configured to be deflected by the first disc spring. The first and second shock isolators exhibit first and second combined load-deflection curves that include a constant load region.

A zero-stiffness impact isolation device includes a shell, a half-hourglass-shaped boss, a sliding block, a spring, a motion guide assembly, and an inner core. Where the motion guide assembly includes a linear bearing fixed to the shell and the inner core and a corresponding sliding rod, and is divided into a transverse guide assembly and a longitudinal guide assembly. The spring is sleeved outside the sliding rod of the transverse motion guide assembly, and two ends of the spring are in contact with the sliding block and the inner core, respectively. When the device suffers from external impact load, the inner core and the separated object carry out a reciprocating motion, the sliding block is extruded by the half-hourglass-shaped boss to move side to side with respect to the inner core, and the spring provides elastic force to the sliding block in the process.

A horizontally arranged six-degree-of-freedom constant-stiffness mechanism is provided, and includes an upper platform, a bottom plate, three composite spherical hinges, spherical hinges, support rods, guide rail slider assemblies, and six electromagnetic adjustable stiffness units. Two ends of a shaft on which a permanent magnet is fixed in each electromagnetic adjustable stiffness unit are fixed to the bottom plate via shaft supports. Axially moving housings of electromagnetic adjustable stiffness units are fixed on sliders of the guide rail slider assemblies via slider backing plates respectively. Guide rail slider assembles are fixed on the bottom plate. Tops of the housings are mounted with the spherical hinges respectively. A bottom of the upper platform is uniformly mounted with the composite spherical hinges. One end of each support rod is threadedly connected to a corresponding one of the spherical hinges, and another end is connected with a corresponding one of composite spherical hinges.

Various implementations include a device for controlling vibration with piecewise-linear nonlinearity. The device includes a stiffness element, a mass, a stopper, and an actuator. The stiffness element is expandable and compressible along an axis. The mass is coupled to the stiffness element. The mass has a resting mass position along the axis. The actuator is coupled to the stopper. The actuator is configured to move the stopper along the axis to vary a gap size. The gap size is measured as a distance between the resting mass position and a resting stopper position.

The bushing includes an outer cylinder, an inner cylinder, and an elastic body therebetween. The outer cylinder has a central recess portion recessed from the inner peripheral surface in the radial direction at the central portion in the axial direction, and the thickness of both end portions is thicker than the thickness of the central portion. The central recess portion is formed in a curved shape or having a curved and a straight shape. The inner cylinder has a central convex portion swelling from the outer peripheral surface in the radial direction at a position corresponding to the central recess portion. The maximum outer diameter of the central convex portion is larger than the minimum inner diameter of the inner peripheral surface of the outer cylinder.

A bearing assembly configured to be disposed on casing of electronic device and including plate body, first damping component, second damping component, first fastener and second fastener. The plate body includes first mounting hole and second mounting hole. The first damping component is disposed in the first mounting hole. The first damping component includes first hole. The second damping component is disposed in the second mounting hole. The second damping component includes second hole. The first fastener is disposed in the first hole of the first damping component and configured to be fixed to the casing of the electronic device. The second fastener is disposed in the second hole of the second damping component and configured to be fixed to the casing of the electronic device. A hardness of the first damping component is greater than a hardness of the second damping component.

An isolator assembly includes a bracket, a first isolator connected to the bracket, a second isolator connected to the bracket, and/or a mass connected to the bracket via the first isolator and the second isolator. The first isolator and the second isolator may include a plurality of legs. The first isolator may include a first radial flange and a second radial flange. The first radial flange and the second radial flange may be axially spaced from each other. An outer diameter of the first radial flange may be larger than an outer diameter of the second radial flange. A distance between the first radial flange and the second radial flange may correspond to a thickness of the bracket.

A horizontally arranged six-degree-of-freedom constant-stiffness mechanism is provided, and includes an upper platform, a bottom plate, three composite spherical hinges, spherical hinges, support rods, guide rail slider assemblies, and six electromagnetic adjustable stiffness units. Two ends of a shaft on which a permanent magnet is fixed in each electromagnetic adjustable stiffness unit are fixed to the bottom plate via shaft supports. Axially moving housings of electromagnetic adjustable stiffness units are fixed on sliders of the guide rail slider assemblies via slider backing plates respectively. Guide rail slider assembles are fixed on the bottom plate. Tops of the housings are mounted with the spherical hinges respectively. A bottom of the upper platform is uniformly mounted with the composite spherical hinges. One end of each support rod is threadedly connected to a corresponding one of the spherical hinges, and another end is connected with a corresponding one of composite spherical hinges.

A roll mount device for a vehicle includes: a front mount configured to be connected to a power train; a rear mount configured to be connected to a vehicle body; and a rod disposed between the front mount and the rear mount. The front mount comprises: a core configured to be connected to the power train to receive vibration transmitted from the power train; an outer pipe disposed outside the core and spaced from the core by a predetermined distance with respect to a radial direction of the core; an elastic body disposed between the core and the outer pipe to absorb vibration transmitted thereto from the core; and a stopper disposed on an outer surface of the core to be spaced from an inner surface of the outer pipe by a predetermined distance.