The present disclosure is an electromagnetic force control method of a magnetic disk type negative stiffness electromagnetic actuator. The present disclosure relates to the technical field of vibration control. According to the actually required static bearing capacity, the present disclosure determines the positive stiffness k of a mechanical spring required for a magnetic disk type quasi-zero stiffness vibration isolator; and establishes an electromagnetic force mathematical model of a single electromagnet under a condition of magnetic unsaturation. The present disclosure aims at the magnetic disk type quasi-zero stiffness vibration isolator and takes the coil current as an input control variable, so that the electromagnetic force and displacement of the negative stiffness electromagnetic actuator have a linear relationship, thereby changing the non-linear nature of a vibration isolation system, avoiding the multi-stable phenomenon caused by the non-linear electromagnetic force during working, and eliminating complex dynamic behaviors such as jumping when the whole vibration isolator works. Complex sensors and control systems are not needed, and implementation manners are simple and convenient.

An energy-absorbing structure for a vibration isolator includes a conical disc spring member having a first end including a central opening and a second end opposite the first end. The structure also includes at least one spacer having a base portion with a first side. The base portion first side defines a cavity structured to receive therein a second end of the spring member. The cavity has a floor, and a second end of the spring member is positioned in contact with the floor. The floor includes an opening formed therein and positioned so as to reside opposite the first end of the spring member when the second end of the spring member is positioned in contact with the cavity floor. The opening is structured to receive at least a portion of the first end of the spring member therein during an inversion of the spring member.

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.

Systems, apparatus, and methods provide a material, comprising a first section including a first plurality of geometric elements associated with a first characteristic, the first section having a first set of mechanical properties; a second section including a second plurality of geometric elements associated with a second characteristic, the second section having a second set of mechanical properties different from the first set of mechanical properties; and a third section including a third plurality of geometric elements having a change in configuration that provides a transition from the first characteristic to the second characteristic.

A vibration damping device for reducing vibration of an elevator rope includes a displacement amplifier arranged around a region from a first portion of the elevator rope drawn and a second portion of the elevator rope drawn from an opposite side of one or more sheaves in parallel with the first portion. The displacement amplifier is configured to amplify a displacement of each of the first portion and the second portion of the elevator rope. The device also includes a limiting member that controls displacement amplification performed by the displacement amplifier such that the displacement of the first portion or the second portion amplified by the displacement amplifier does not become greater than a first displacement, which is a displacement of the elevator rope by which the elevator rope is not allowed to return to an equilibrium position of the vibration.

The disclosure provides a magnetic suspension type quasi-zero stiffness electromagnetic vibration isolator with active negative stiffness. The disclosure relates to the technical field of vibration control. The disclosure can selectively realize passive negative stiffness and active negative stiffness by adjusting the control mode of a controller. By adopting an amplifying mechanism and DIESOLE type electromagnets, the bearing capacity of the vibration isolator is further increased, and the disclosure is suitable for the field of ultra-low frequency heavy load vibration reduction and isolation. The displacement state of a negative stiffness mechanism can be measured in real time according to a sensor, and by means of cooperation of the controller and a driver, active negative stiffness is realized, real-time linear negative stiffness is realized, the multi-stable phenomenon is avoided, and complex dynamic phenomena such as jumping during working of the vibration isolator are prevented. The active negative stiffness is realized, the current passing through the system can be adjusted according to different working conditions, and the system has strong self-adaptive ability, can be applied to vibration-isolated objects of different quality, and can adapt to different working environments.

An isolation system and method are disclosed. The isolation system includes a beam that includes a first end and a second end. The isolation system may include at least one clamping block comprising first elastomeric material, and the first end may be coupled with the first elastomeric material by the at least one clamping block. An end condition of the buckling beam may be varied based on compression stiffening of the first elastomeric material.

A negative stiffness shell has a convex first position, but can transition or snap to a concave second position under a force applied to the exterior surface of the shell in the convex first position. During the transition, the shell exhibits negative stiffness that permits a large amount of energy to be absorbed. The negative stiffness shell can withstand a high initial force threshold prior to transitioning. In the second, concave position the shell can still resist force. Moreover, it is possible for the shell to revert back to the first, convex position with minimal plastic deformation for subsequent use. The negative stiffness shells can be used collectively and/or in layers to increase the efficiency of the overall negative stiffness shell unit.

An object of the invention is to provide a vibration damping system that can avoid the occurrence of resonance of an elevator rope regardless of the vibration frequency of a vibration source. A vibration damping system (200) includes a displacement amplifier (7), a calculation unit (66), and a displacement amplification control unit (67). The displacement amplifier (7) is arranged along a given position in the longitudinal direction of the elevator rope. The displacement amplifier (7) amplifies a displacement due to vibration of the elevator rope based on a variable amplification factor. The calculation unit (66) calculates the natural frequency of the elevator rope. The displacement amplification control unit (67) controls the displacement amplification of the displacement amplifier (7) based on the natural frequency calculated by the calculation unit (66) and a preset vibration frequency.

An object of the present invention is to provide a vibration damping device including an instability preventing means, for efficiently suppressing amplification of vibration of a long structure, which is mechanically flexible, due to a resonance phenomenon. A vibration damping device (100) for reducing vibration of a long structure (1) includes a displacement amplifier (7) and limiting members (8). The displacement amplifier (7) is arranged along a given position in the longitudinal direction of the structure (1). The displacement amplifier (7) amplifies a displacement of the structure (1). The limiting members (8) control displacement amplification performed by the displacement amplifier (7) such that the displacement of the structure (1) amplified by the displacement amplifier (7) does not become greater than a first displacement, the first displacement being a displacement of the structure (1) by which the structure (1) is not allowed to return to the equilibrium position of the vibration.