160 results about "Mechanical metamaterial" patented technology

The invention relates to a negative Poisson's ratio metamaterial cell element structure based on a three-rod tension structure, which belongs to the field of mechanical metamaterials and comprises a three-rod tension integral structure component and a degree-of-freedom constraint component. Under the action of a three-rod nine-cable tension integral structure, when the structure is not subjected to external load, the structure is subjected to interaction of internal stress, and the balance is achieved in a self-stabilization state; and under the state of external load, the upper surface and the lower surface can generate a torsion effect, and the structure can recover to the initial state after the external load is removed again. The negative Poisson's ratio metamaterial cell element structure based on the three-rod tension structure has the advantages of self-adaptability, self-recovery, compression-torsion characteristic and the like. The tensegrity structure and the mechanical metamaterial structure are combined, the types of existing mechanical metamaterial cell element structures are enriched, and a brand new direction is opened up for design, analysis and application of the tensegrity mechanical metamaterial structure.

The invention belongs to the technical field of electromagnetic protection, and relates to an electromagnetic protection device based on mechanical wave nonlinear attenuation, which comprises a piezoelectric substrate, and a signal input component, a nonlinear attenuation component and a signal output component which are sequentially arranged on the piezoelectric substrate at intervals, the nonlinear attenuation component comprises an energy absorption structure, a deformation structure and a rigid connection structure. The energy absorption structures are made of energy absorption materials and are arranged above the piezoelectric substrate at intervals; the deformation structure is made of a mechanical metamaterial, and two ends of the deformation structure are respectively connected with the energy absorption structure and the piezoelectric substrate; one end of the rigid connection structure is connected with the energy absorption structure, and the other end is spaced from or abutted against the piezoelectric substrate; the signal input component converts electromagnetic wave signals into mechanical waves, the nonlinear attenuation component deforms under propagation of the mechanical waves, the deformation quantity is in direct proportion to the strength of the mechanical waves, and the signal output component converts the mechanical waves into the electromagnetic wave signals and outputs the electromagnetic wave signals. According to the invention, electromagnetic protection can be realized based on mechanical wave nonlinear attenuation.

The invention relates to a negative Poisson's ratio metamaterial cell element structure based on a four-rod tension structure, which belongs to the field of mechanical metamaterials and comprises a four-rod tension integral structure component and a degree-of-freedom constraint component. Under the action of a four-rod twelve-cable tensioning integral structure, when the structure is not subjected to external load, the structure is balanced in a self-stabilizing state under the interaction of internal stress; and under the state of external load, the upper surface and the lower surface can generate a torsion effect, and the structure can recover to the initial state after the external load is removed again. The negative Poisson's ratio metamaterial cell element structure based on the four-rod tension structure has the advantages of self-adaptability, self-recovery, compression-torsion characteristic and the like. The tensegrity structure and the mechanical metamaterial structure are combined, the types of existing mechanical metamaterial cell element structures are enriched, and a brand new direction is opened up for design, analysis and application of the tensegrity mechanical metamaterial structure.

The invention relates to the technical field of mechanical metamaterials, in particular to a negative Poisson's ratio cell element with an embedded symmetrical broken subcell structure, which comprises a concave hexagonal main body, the concave hexagonal main body comprises two horizontal cell walls and inclined cell walls arranged at two ends of the two horizontal cell walls, and the central points of the two inclined cell walls are bent towards one side close to the central points of the horizontal cell walls; the number of the bent wall rods is two, and the two bent wall rods are symmetrically arranged in the inwards-concave hexagonal body. The inherent contradiction that the stretching performance must be sacrificed when the rigidity of a traditional concave honeycomb structure is improved is successfully solved, and the negative Poisson's ratio effect and the energy absorption capacity of the structure can be further improved while the structural rigidity is enhanced.

The invention discloses a sandwich structure based on chiral pressure torsion and negative poisson ratio honeycomb compounding, and relates to the technical field of mechanical metamaterials. The sandwich structure comprises an upper skin layer, a core layer and a lower skin layer, the core layer is formed by alternately compounding three-dimensional chiral compression-torsion cell elements and negative poisson ratio honeycomb cell elements which are periodically arranged, and the chiral compression-torsion cell elements form a bidirectional torsion stress network through spiral connecting rods; the negative Poisson's ratio honeycomb cell element is of a concave polyhedron structure and is nested with a butterfly-like substructure, and energy is absorbed through transverse contraction and folding deformation in a cooperative mode. The sandwich structure has a multi-stage energy dissipation mechanism: the chiral compression-torsion unit disperses impact energy through spiral deformation, the butterfly-like substructure elastically shrinks at low strain and slides and folds at high strain, and the energy absorption efficiency is enhanced through friction and plastic deformation; the structural parameters can be subjected to gradient regulation and control according to the impact strength, the lightweight rate and the deformation mode, and high design flexibility and working condition adaptability are achieved.

The invention relates to a multistable mechanical metamaterial structure with a tension characteristic, which belongs to the field of mechanical metamaterials and mainly comprises a multistable mechanical metamaterial cell structure, and the multistable mechanical metamaterial cell structure comprises a tension integral structure component, a degree-of-freedom constraint component and a connecting component. Under the action of a tensioning integral structure, when the structure is not subjected to external load, the structure is subjected to interaction of internal stress, and the balance is achieved in a self-stabilization state; according to the multistable mechanical metamaterial cell element structure with the tension characteristic, the structure of the position where each side of the square outline is located has two steady-state configurations, and the cell element structures are connected through a rectangular array to form the multistable mechanical metamaterial structure with the tension characteristic. The tensegrity structure and the mechanical metamaterial structure are combined, the types of existing mechanical metamaterial cell element structures are enriched, and a brand new direction is opened up for design, analysis and application of the tensegrity mechanical metamaterial structure.

The invention relates to a mechanical metamaterial structure based on a six-rod and six-cable tensegrity structure, and belongs to the field of mechanical metamaterials, the mechanical metamaterial structure comprises a six-rod and six-cable tensegrity cell structure, and the tensegrity cell structure comprises corner assemblies, first connecting shafts, fixing rings and middle tensegrity assemblies; under the action of the middle tensioning assembly, when the structure is not subjected to an external load, the structure is subjected to interaction of internal stress, and the balance is achieved in a self-stabilization state; under the state of being subjected to an external load, the structure can generate self-adaptive deformation; and the external load is removed again, and the structure can recover to the initial state. The mechanical metamaterial structure based on the six-rod six-cable tensegrity structure has the advantages of adaptivity, isotropy, negative Poisson's ratio and the like, the tensegrity structure and the mechanical metamaterial structure are combined, and the types of existing mechanical metamaterial cell element structures are enriched; and a brand new direction is opened up for the design, analysis and application of the tensioning mechanical metamaterial structure.

A star-shaped negative Poisson's ratio honeycomb structure with double stress platforms comprises a plurality of star-shaped cell elements which are periodically arranged in the same plane in the transverse direction and the longitudinal direction, and each star-shaped cell element comprises a quadrangular star-shaped structure, a circular structure and two double-arrow-shaped structures; the quadrangular star-shaped structure is formed by connecting eight inclined cell walls end to end, so that a closed hollow structure which is symmetrical in the up-and-down and left-and-right directions is formed; the circular structure is embedded in the quadrangular star-shaped structure and intersects with four concave points of the quadrangular star-shaped structure; the two double-arrow-shaped structures are located on the left side and the right side of the quadrangular star-shaped structure respectively, each double-arrow-shaped structure comprises two long cell walls and two short cell walls, and the intersection point of the two long cell walls coincides with the inward concave point of the quadrangular star-shaped structure. Under the action of longitudinal compression, the double-stress-platform characteristic is shown, the good negative Poisson's ratio effect is achieved, the structural bearing capacity and the energy absorption efficiency can be improved, and the double-stress-platform metamaterial belongs to the technical field of mechanical metamaterials.

The invention belongs to the technical field of mechanical metamaterials, and particularly discloses an energy-absorbing three-dimensional metamaterial with interactive combination of positive and negative Poisson's ratio structures, which comprises a plurality of microcosmic unit structures, each microcosmic unit structure comprises a reverse four-chiral auxetic structure and a bionic diagonal bracing structure, and the reverse four-chiral auxetic structures and the bionic diagonal bracing structures are arranged in an interactive combination manner. According to the technical scheme, the microscopic unit structures are three-dimensional structures and are simple in structure, the lattice metamaterial obtained by combining the microscopic unit structures has good isotropic characteristics and has three-stage strain hardening characteristics under the compression effect, the plastic deformation capacity is enhanced, the energy absorption capacity of the structures is effectively improved, and the energy absorption efficiency of the structures is improved. And the bearing capacity is relatively high. The structure size of the metamaterial can be flexibly adjusted according to an actual scene, and the metamaterial can be used as a part or a structural member to be flexibly applied to different fields.

A mechanical metamaterial adaptive to an applied stress comprises a plurality of meta-capsules arranged in a lattice structure. Each meta-capsule comprises a plurality of rigid parts and a plurality of elastically deformable soft parts coupled to the plurality of rigid parts, such that at least a subset of the plurality of meta-capsules undergo a reconfiguration under the applied stress. The reconfiguration includes a deformation of the soft parts of the meta-capsules in the subset, and a reduction of a gap between adjacent rigid parts of the meta-capsules in the subset, thereby increasing a stiffness of the mechanical metamaterial from a first stiffness to a second stiffness when the adjacent rigid parts come into contact.

The invention relates to a negative Poisson's ratio two-dimensional unit cell structure and a negative Poisson's ratio material, and belongs to the technical field of mechanical metamaterials. A quadrangular star-shaped main body of each quadrangular star-shaped unit is formed by sequentially connecting and encircling four first V-shaped rod bodies through opening ends, a first concave part is formed at the joint, and a first connecting rod is connected to the outer side of the first concave part; a double-arrow main body of the double-arrow unit is formed by a second V-shaped rod body through primary mirroring by taking a connecting line of two end points of an opening end as a symmetry axis, one end of the double-arrow main body is an arrow tip, the other end of the double-arrow main body is a second inner concave part, and a second connecting rod is connected to the outer side of the second inner concave part; according to the set number of the double-arrow units, the negative Poisson's ratio two-dimensional unit cell structure comprises a single-side arrow configuration and a double-side arrow configuration. The negative Poisson's ratio two-dimensional unit cell structure obtains a negative Poisson's ratio material through periodic arrangement in a plane. The negative Poisson's ratio characteristic is achieved through a simple structure.

A self-aware composite mechanical metamaterial, comprising first and second electrically conductive components disposed relative to each other to act as opposite electrodes to induce contact electrification; wherein the first and second electrically conductive components, along with a dielectric component serving as a skeleton of the self-aware composite mechanical metamaterial, form a lattice of snapping curved semicircular-shaped segments, wherein each of the snapping curved semicircular-shaped segments has an elastic snap-through instability mechanism; and wherein the lattice comprises periodic repeatable parallel rows of the snapping curved semicircular-shaped segments.

The invention discloses a mixed star-shaped mechanical metamaterial unit and a metamaterial structure, and relates to the technical field of metamaterial structures, the mixed star-shaped mechanical metamaterial unit comprises a concave polygonal honeycomb structure which is of a central symmetry structure and is provided with a long edge and short edges which are bent inwards, and two ends of the long edge are respectively connected with one ends of the two short edges to form a closed structure; the two concave polygonal honeycomb structures are respectively arranged along an X axis and a Y axis and have the same symmetric center, and the long sides of the two concave polygonal honeycomb structures define a star-shaped structure by taking the symmetric center as a base point; the short edge is bent inwards to form a mounting part matched with the vibration reduction assembly in shape, and the vibration reduction assembly is arranged on the mounting part; the straight line where the two ends of the short edge are located is a base line. The outer edge of the damping assembly is located outside the base line. Each mixed star-shaped mechanical metamaterial unit is composed of two inwards-concave polygonal honeycomb structures and a vibration reduction assembly, and has the large-load bearing capacity and the vibration isolation function.

The invention discloses a compression-torsion buckle unit and a variable-rigidity buckle type compression-torsion coupling mechanical metamaterial, relates to the technical field of mechanical metamaterials, and solves the problems that an existing compression-torsion coupling mechanical metamaterial is limited in energy absorption capacity and fixed in rigidity. A plurality of pressing and twisting buckle units are arranged between the upper pressing plate and the lower pressing plate. The pressure torsion buckle unit comprises an upper support, a plurality of pressure torsion bars, a curved bar and a plurality of buckles, the curved bar comprises a plurality of curved arms and a lower support, and the upper support and the lower support are of a radial structure, are the same in structure and are connected through the pressure torsion bars; the lower bracket is rotationally arranged in the groove of the lower pressing plate, and each end part of the lower bracket is provided with a bent arm; a buckle is arranged on the bent arm and matched with the sawtooth-shaped groove wall of the groove. According to the invention, the compression-torsion coupling mechanical metamaterial is combined with the buckle type metamaterial, and effective absorption of energy is realized through the mechanical multistable effect of the buckle and the compression-torsion deformation effect of the compression-torsion coupling mechanical metamaterial; the rigidity is effectively adjusted by changing the positions of the buckles.

The invention relates to the technical field of computer aided design, and provides a mechanical metamaterial generative reverse design method and device, and the method comprises the steps: generating a basic microstructure data set based on a k-uniform tiling algorithm and a Voronoi diagram generation algorithm, obtaining a microstructure data set through seed translation, local weight variance increase and global weight variance modification and expansion; performing full-field finite element simulation on microstructure samples in the microstructure data set to obtain a physical field video data set; constructing a video diffusion model, training the video diffusion model by taking the physical field video data set as training data, and taking the trained video diffusion model as a microstructure generator; and the microstructure generator carries out structural design and evaluation according to the input target performance index, and outputs an optimal microstructure. According to the method, under the constraint of physical field video data, the corresponding relation between the nonlinear mechanical response and the complex geometric configuration can be accurately learned, and unification of physical consistency and structural innovation is achieved.

The invention discloses a mechanical metamaterial cell element with a zero Poisson's ratio property, and belongs to the technical field of mechanical metamaterials. The upper top plate and the lower bottom plate are symmetrically arranged, the upper cleat nail set and the lower cleat nail set are arranged at the four corners of the inner side faces of the upper top plate and the lower bottom plate, the elastic body set is connected through the upper cleat nail set and the lower cleat nail set, and the flexible hinge component set is arranged at the midpoint position of four side lines of the upper top plate and the lower bottom plate. The flexible hinge component set keeps inward pre-bending through the pre-tension of the elastomer set, and when the cell element bears an axial load, the flexible hinge component set generates coordinated inward bending deformation, so that the cell element shrinks in the axial direction, the transverse size is kept stable, the axial zero Poisson's ratio characteristic is achieved, and meanwhile the energy absorption capacity is achieved. The cell element is based on elastic deformation, has self-recovery capability and long cycle life, adopts modular design, is convenient to assemble, disassemble and maintain, and is suitable for application scenes of aerospace buffer devices, biomedical implants, precise instrument supporting structures and the like.

Mechanical metamaterial passive wireless sensors and methods of use thereof are disclosed. An example sensor includes a flexible substrate having multiple extending arms; at least one temperature responsive actuator coupled to the substrate; and an antenna embedded within the substrate and extending along at least a portion of the multiple extending arms, the antenna configured to deform with the substrate. The substrate may be configured to be activated upon exposure of the at least one temperature responsive actuator to an environmental temperature that exceeds a threshold, and further configured to transform into at least one three-dimensional configuration in response to a duration of immersion in a liquid following the activation, the three-dimensional configuration causing a detectable change in electromagnetic signal characteristics of the antenna.

The invention relates to the technical field of mechanical metamaterial additive manufacturing, and discloses a 3D printing deformation-recoverable shape memory alloy mechanical metamaterial which comprises the following steps: S1, defining the shape, the geometric dimension and the design boundary of a mechanical metamaterial unit according to the use environment requirement and the processing and manufacturing requirement of the mechanical metamaterial; s2, completing the design and drawing of a two-dimensional line diagram of the mechanical metamaterial unit; s3, constructing a three-dimensional unit grid model based on the mechanical metamaterial unit two-dimensional line graph; s4, a corresponding shape memory alloy component system is selected, and the structure and the phase change temperature of the mechanical metamaterial are further regulated and controlled through alloy component proportion optimization, 3D printing process parameter optimization and aftertreatment system formulation; and S5, preparing the deformation-recoverable shape memory alloy mechanical metamaterial through a 3D printing technology according to the optimized 3D printing process parameters. The mechanical properties such as the elastic modulus, the yield strength and the Poisson ratio can be manually regulated and controlled.

The invention discloses a design method of a mechanical metamaterial based on 3-order magic cube digital coding, and the method comprises the following steps: S1, simplifying and calibrating orthotropic unit cells as magic cube blocks, and formulating a sequence rule of the arrangement of the magic cube blocks according to the spatial arrangement characteristics of the orthotropic unit cells; s2, according to the spatial combination and arrangement of the magic cube blocks, constructing a 3-order magic cube regulation and control model with programmable control characteristics; and S3, through performance characterization and judgment, carrying out performance inspection on the 3-order magic cube regulation and control model, carrying out functional structure directional design or optimization design through constraint conditions to obtain a target structure, and constructing the performance-programmable mechanical metamaterial. According to the invention, through digital coding and the magic cube frame, the arrangement of the magic cube blocks is adjusted as required, a target structure with specific performance is designed, and the performance of the mechanical metamaterial is controlled.

The invention discloses a self-resetting damper based on mechanical metamaterial axial pressure driving transverse cooperative instability. The damper is composed of metamaterial units arranged periodically, and each unit comprises inner left / right arc-shaped beams with opposite concave surfaces, outer left / right arc-shaped beams with opposite convex surfaces, inner / outer upper and lower fixing plates, a vertical supporting beam and left / right transverse connecting beams. The end parts of the inner and outer left / right arc-shaped beams are connected with inner / outer upper and lower fixing plates which are arranged in parallel; the middle of the vertical support beam is connected with the inner upper-lower fixing plate; the inner and outer arc-shaped beams are connected through left / right transverse connecting beams. The outer beam is bent inwards under shaft pressure, and the inner beam is driven to move inwards cooperatively to generate jumping instability. The multiple units are connected in series, and energy is consumed through continuous instability. The damper can be made of steel or a carbon fiber composite material, and the strength, rigidity and energy consumption characteristics can be customized by adjusting the geometric parameters of the arc-shaped beam and the topological configuration of the unit. In the deformation process, all components are kept in an elastic state, and the excellent self-resetting capacity is achieved.

The invention discloses a phase change flexible mechanical metamaterial with adjustable and controllable deformation. The phase change flexible mechanical metamaterial comprises a plurality of lattice units which are mainly composed of a series of basic driving units arranged in a set pattern and first configuration connecting pieces or second configuration connecting pieces, the basic driving units are bonded and fixed to the first configuration connecting pieces or the second configuration connecting pieces, and the first configuration connecting pieces are of L-shaped structures. The first configuration connecting piece is of a plate-shaped structure, the second configuration connecting piece is of a plate-shaped structure, each basic driving unit is provided with a fixed side and a deformation side, the fixed side is fixedly bonded with the first configuration connecting piece or the second configuration connecting piece, the deformation side is used for generating deformation, and each basic driving unit can be independently controlled. The deformation-controllable phase change flexible mechanical metamaterial can repeatedly and reversibly realize abundant and diversified controlled deformation, can keep deformation without power consumption, greatly expands the deformation form of limited liquid-gas phase change flexible driving in the prior art, and has a relatively great application prospect.

Methods and devices are provided for fabricating and employing patient immobilization devices during radiation treatment procedures. Immobilization devices are provided that include a thin conformal shell configured to conform to an anatomical region of a patient that is to be exposed to radiation during a radiation treatment procedure, with a rigid lattice structure extending outwardly, in an external, beam-facing direction, from the conformal shell. The rigid lattice structure confers structural rigidity to the device, and the thin cellular regions mitigate the impact of the device on a surface dose delivered to the patient or subject. The present mechanical-metamaterial-based immobilization devices incorporate structural features that confer advantageous mechanical properties and radiation transmissive properties when compared with conventional solid or mesh-based immobilization devices used in radiation therapy.

The invention discloses a negative Poisson's ratio tubular energy absorption structure based on bimodal compression-torsion coupling, and belongs to the technical field of mechanical metamaterial and structural engineering vibration reduction and impact resistance. The device comprises an outer shell, an upper inner circular ring, a lower inner circular ring, an upper end frame plate, a lower end frame plate and supporting rods. The upper end frame plate and the lower end frame plate are coaxially arranged up and down, and the outer shell is installed between the opposite end faces of the upper end frame plate and the lower end frame plate. The upper inner circular ring and the lower inner circular ring which are positioned in the outer-layer shell are coaxially arranged up and down, and an axial distance exists between the end surfaces of the upper inner circular ring and the lower inner circular ring; the upper inner circular ring is connected with the coaxially-arranged upper end frame plate through a first set of obliquely-arranged supporting rods, and the lower inner circular ring is connected with the coaxially-arranged lower end frame plate through a second set of obliquely-arranged supporting rods. The impact resistance and the energy absorption characteristic of the structure are remarkably improved by ingeniously fusing a heterogeneous bimodal mechanism of outer layer negative Poisson's ratio compression contraction torsion and inner layer inclined strut independent compression torsion.

The invention provides a manufacturing method for a space station protection structure and the space station protection structure, and relates to the technical field of space station protection. The manufacturing method for the space station protection structure comprises the steps that a shape memory composite material support is manufactured through chiral auxetic mechanical metamaterial cell elements, the chiral auxetic mechanical metamaterial cell elements comprise a plurality of wavy ligaments in an annular array and circular ring nodes, the wavy ligaments can be curled and relaxed through the shaping process, and the shape memory composite material support is manufactured through the shape memory composite material support. The circular ring nodes can be expanded and shrunk through the shaping process; a 3D printing ceramic composite board is manufactured in a space station through a 3D printing technology; a polyimide film is attached to the 3D printing ceramic composite board; and the 3D printing ceramic composite plate is installed on the shape memory composite material support, and the shape memory composite material support is used for being installed on the space station. The shape memory composite material support, the 3D printing ceramic composite plate and the polyimide film can form a protective shell on the space station, and the impact resistance of the space station is improved.

The invention discloses a snakelike arm structure based on a negative Poisson's ratio metamaterial. A snakelike mechanical arm is obtained by assembling a plurality of mechanical metamaterial structural bodies. The mechanical metamaterial structural body is composed of an external frame unit capable of elastically deforming and bionic scales; the elastically-deformable outer frame unit is formed by arranging four connecting rods between a vertical rod A and a vertical rod B which are arranged in parallel. The elastically deformable outer frame unit has an elastic deformation characteristic of the flexible mechanism. The mechanical metamaterial structural body is divided into a first plane and a second plane from the space structure, the second plane tilts upwards by a certain angle alpha relative to the first plane, the alpha forms a micro-convex bionic scale structure with a certain backward angle, the highly asymmetric pawl characteristic with one sharp side and the other gentle side is shown, and the mechanical metamaterial structural body is formed. Therefore, the mechanical metamaterial structural body forms friction anisotropy in the scale blade direction, namely, different friction forces are shown in different movement directions.

The application belongs to the technical field of mechanical metamaterials, and particularly relates to a self-similar layered negative Poisson's ratio cell and a honeycomb structure thereof. The self-similar layered negative Poisson's ratio structure replaces the corner points of the traditional structure with similar star-shaped structures on the basis of the traditional star-shaped structure. When the structure is subjected to low-speed impact, the adjacent cells will first form self-similar star-shaped structures due to the unique configuration, and only after all the self-similar star-shaped structures are formed, the cell walls of the cells will begin to contact each other and deform, so that the self-similar layered negative Poisson's ratio structure can have more superior energy absorption capacity and higher platform stress while maintaining the negative Poisson's ratio effect.

A composite mechanical metamaterial, comprising first and second electrically conductive components disposed relative to each other to act as opposite electrodes to induce contact electrification; wherein the first and second electrically conductive components, along with a dielectric component serving as a skeleton of the composite mechanical metamaterial, form a lattice of snapping curved semicircular-shaped segments, wherein each of the snapping curved semicircular-shaped segments has an elastic snap-through instability mechanism; and wherein the lattice comprises periodic repeatable parallel rows of the snapping curved semicircular-shaped segments.

The present disclosure relates to a mechanical metamaterial with a variable bistable state. The mechanical metamaterial comprises a plurality of metamaterial unit cells connected in sequence in a first direction. Each metamaterial unit cell comprises a connecting head, a variable part and a fixed part connected in sequence in the first direction. The variable part comprises a plurality of variable sheet groups, each variable sheet group comprising two variable sheets, each variable sheet having a top end connected to the connecting head and a bottom end connected to the fixed part, and the width of each variable sheet increasing from the top end to the bottom end. The two variable sheets of each variable sheet group are symmetric about the axis center of the connecting head. The fixed part has a cavity facing the connecting head, and when an axial load is applied to the top of the connecting head, the top end of the variable sheet is bent in the direction of the cavity under the action of the connecting head, and part of the variable sheet and part of the connecting head can be accommodated in the cavity at the top of the fixed part. The mechanical metamaterial of the present disclosure can maintain stable and large deformation and has good band gap regulation ability.

The present invention discloses a reverse design method for a non-linear response mechanical metamaterial structure based on a neural network, which relates to the technical fields of metamaterial structures and machine learning, and solves the technical problems of long time consumption and high calculation cost in the design of mechanical metamaterials. The key points of its technical solution are to change the shape parameters of the smallest periodic unit in the mechanical metamaterial, adjust the amount of internal rotation of the unit in the metamaterial structure caused by external forces, and obtain the non-linear mechanical response of the metamaterial; introduce a neural network model to economically and efficiently describe the relationship between the geometric parameters of the mechanical metamaterial and its stress-strain response; combine the neural network with an evolutionary strategy to effectively identify the structure of the mechanical metamaterial and obtain the target non-linear mechanical response, thereby constructing a reverse design model of the mechanical metamaterial structure and designing more effective energy absorption systems, soft robots, wearable structures, etc.

The invention provides a tensegrity inspired buffer mechanical metamaterial structure, which relates to the technical field of buffer materials and comprises an upper-layer buckling structure, an upper-layer connecting structure, a lower-layer connecting structure and a lower-layer buckling structure, the upper-layer buckling structure and the lower-layer buckling structure are correspondingly arranged in the vertical direction and cover the outer side of the upper-layer connecting structure and the outer side of the lower-layer connecting structure correspondingly. The upper-layer buckling structure and the upper-layer connecting structure are both circumferential array structures and respectively comprise buckling units and connecting units which are in one-to-one correspondence in number; each buckling unit comprises a supporting framework, a deformation main body, a supporting seat and a connecting interface; each connecting unit comprises a connecting part and a coupling part used for being matched with the buckling unit; the inner connecting bulge of the buckling unit and the coupling part of the connecting unit form embedded coupling connection; the upper-layer outer connecting protrusions of the upper-layer buckling structure and the corresponding outer connecting protrusions of the lower-layer buckling structure are directly and fixedly connected at the central plane of the metamaterial.