4results about How to "Improve low frequency vibration isolation performance" patented technology

The application relates to the technical field of new materials, and discloses a quasi-zero stiffness unit suitable for different tensile loads, a metamaterial vibration isolation structure and a design method, which comprise a first rigid side wall and a second rigid side wall, a positive stiffness unit is arranged in the center of the first rigid side wall, a negative stiffness unit is arranged at the opening of the top of the first rigid side wall, and one end of the second rigid side wall is connected with the vertex of the positive stiffness unit and extends upwards through the negative stiffness unit. The application realizes the regulation and control of the stiffness response of the structure under the action of different loads by parameterizing the design and multi-level combination of the tensile unit configuration and combining the interaction of the positive stiffness and the negative stiffness, the quasi-zero stiffness platform of the structure can be adjusted with the change of the tensile load, so that the stable low dynamic stiffness characteristics of the structure can be maintained within a wide load range, and then the adaptive regulation and control and flexible control of the low-frequency vibration isolation performance are realized.

The three-dimensional vibration isolation device comprises a bottom plate, a top plate, a magnetic isolation sleeve, permanent magnets, springs, excitation coils, a control system and sensors, the top plate and the magnetic isolation sleeve are sequentially connected from the center of the bottom plate to the outer edge of the bottom plate, the magnetic isolation sleeve comprises a first magnetic isolation sleeve and a second magnetic isolation sleeve, the permanent magnets are arranged between the first magnetic isolation sleeve and the top plate, the springs are connected between the first magnetic isolation sleeve and the second magnetic isolation sleeve, the permanent magnets comprise first permanent magnets, second permanent magnets, third permanent magnets and fourth permanent magnets, and a plurality of groups are symmetrically arranged along the circumference of the bottom plate, and the excitation coils are wound on the third permanent magnets. The vibration isolation device can have low dynamic stiffness in three-dimensional directions, can realize quasi-zero stiffness in the horizontal direction, realizes quasi-zero stiffness in the horizontal direction through the parallel connection of magnetic negative stiffness and positive stiffness spring elements, and effectively isolates vibration in multiple directions.

The present application belongs to the field of structural optimization design and vibration control technology, and relates to a bistable quasi-zero stiffness structure reverse topology optimization method based on a double-layer hybrid intelligent algorithm. The method defines material distribution variables within a preset design domain, approximates the optimization target in the form of a target potential energy function, and constructs a multi-objective topology optimization model containing a potential energy deviation term, a volume fraction constraint term and a density gradient penalty term. The outer particle swarm algorithm is used for global search, and the inner gradient descent algorithm is used for local fine convergence, thereby realizing the cooperation of global and local optimization. The method can automatically generate a topology configuration with bistable and quasi-zero stiffness characteristics without explicit geometric assumptions, realize the customized design of structural mechanical properties, and has wide application value for low-frequency vibration isolation, energy absorption and multi-stable mechanism design.

This invention discloses an additive manufacturing-based inertial amplification nonlinear low-frequency vibration isolation metamaterial structure, vibration isolation device, and its performance control method. The vibration isolation metamaterial structure includes a rhombic frame structure, an inertial amplification unit, and a square spring structure. The square spring structure is arranged within the rhombic frame structure, with its two ends connected to a pair of opposite corners of the rhombic frame structure. The elastic extension direction of the square spring structure is parallel to the diagonal of this pair of opposite corners of the rhombic frame structure. The inertial amplification unit has a centrally symmetrical structure, including a rigid rod, two counterweights, and two diagonal rods. The center of symmetry of the inertial amplification unit, the center of the rhombic frame structure, and the center of the square spring structure all coincide in projection. Therefore, the vibration isolation metamaterial structure of this invention significantly widens the bandgap range and enhances low-frequency vibration isolation performance, exhibiting excellent performance in suppressing longitudinal waves in the 0-1000Hz low-frequency range, increasing vibration damping, and energy absorption.