25 results about "Specific energy absorption" patented technology

The invention belongs to the technical field of aircrafts, and discloses a trigger-containing aircraft composite material energy absorption structure analysis method, which comprises the following steps: establishing an external trigger composite material structure model according to actual working conditions; constructing an intra-layer and inter-layer damage coupled progressive damage model; configuring finite element model parameters adaptive to the composite material; integrating simulation results; the crashworthiness of the coupling trigger structure is adjusted and optimized in combination with basic parameters; repeating the steps to verify the optimization effect; and predicting the strength of the composite material by coupling stress strain and damage transfer, revealing a damage failure mechanism and determining an optimal design. The method has the beneficial effects that the failure mode and the load response of the aircraft structure under different impact loads can be accurately captured, and low initial peak load and high specific energy absorption requirements are considered through multi-type triggering collaborative design; reliable technical support is provided for crashworthiness design of composite aircraft structures of aircraft fuselage frames, wing supports and other key structures in the aerospace field.

The invention discloses a vertical-horizontal mixed enhanced selective laser melting lattice structure based on a face-centered cube (FCC) and a preparation method of the vertical-horizontal mixed enhanced selective laser melting lattice structure. According to the method, starting from a basic FCC lattice unit, firstly, an in-plane enhanced transition lattice structure FCC-H (FCC-Horizon) is formed through a crossed structure of an inclined main rod and an auxiliary rod perpendicular to the main rod; the secondary auxiliary rods are distributed in a radial mode to construct a continuous bridging grid by further optimizing the rod piece connecting mode and the diameter proportion, and finally the vertical-horizontal mixed enhanced FCC-VH (FCC-Vertical Horizon) lattice structure is obtained. According to the structure, through the synergistic effect of the inclined main rods and the auxiliary rods perpendicular to the main rods, the compressive strength, the specific stiffness, the specific strength and the specific energy absorption of the structure are remarkably improved while the light weight is kept. According to an experiment, 316L stainless steel powder is adopted, an FCC-VH lattice structure is prepared through a selective laser melting (SLM) technology, the compression deformation mode of the FCC-VH lattice structure is converted into multi-node cooperative bearing from local buckling of a basic FCC, and the overall compression performance is more remarkably improved.

The invention discloses a preparation method of an automobile energy absorption box filled with a bionic double-chiral structure, and relates to the technical field of automobile collision safety. The scheme that a traditional honeycomb structure is matched with a chiral structure is further optimized, bionic optimization design of the double-chiral structure is achieved and applied to the field of automobile energy absorption boxes, and three bionic optimization structures combining the double-chiral characteristics are established. And experiments prove that through the synergistic effect of the honeycombs and the double chiral units, the peak force of the energy absorption box in the initial collision stage can be effectively reduced, and meanwhile, the specific energy absorption is remarkably improved. Under the impact load effect, the structure shows a more stable and controllable deformation mode, the instability phenomenon of a traditional energy absorption structure is avoided, and an optimized solution is provided for automobile collision safety protection.

The invention relates to a twin thin-walled beam optimization method and device for a vehicle and electronic equipment, and the method comprises the steps: building a twin thin-walled beam multi-angle crashworthiness data set based on a pre-built twin thin-walled beam finite element model; based on geometric parameters and material parameters of the twin thin-walled beam, constructing a reduction design domain meeting multiple targets; a specific energy absorption polynomial agent model and a peak force polynomial agent model are constructed on the basis of a twin thin-walled beam multi-angle crashworthiness data set, and the specific energy absorption polynomial agent model and the peak force polynomial agent model are constructed on the basis of a reduced design domain. And a preset multi-target genetic algorithm-second generation non-dominant sorting genetic algorithm NSGA-II is utilized to perform optimization to obtain optimal parameters of the twin thin-walled beam, so that the twin thin-walled beam is optimized. Therefore, the problem that a plurality of optimization targets conflict in the design process of the thin-walled beam structure in related technologies is solved, the multi-angle crashworthiness design of the twin thin-walled beam for the vehicle is realized, and the efficiency of multi-target optimization design is effectively improved.

The application provides a recycled aluminum ash hollow sphere / aluminum matrix composite foam material and a preparation method thereof, and belongs to the technical field of aluminum industrial solid waste resource recycling and metal material processing. The aluminum matrix is used instead of the resin matrix to prepare the composite foam material, and the aluminum ash is used as the hollow sphere raw material, so that the strength and specific energy absorption of the composite foam material can be significantly improved; after the metal aluminum is extracted, the hollow aluminum oxide particle content in the aluminum ash is relatively high, compared with the aluminum matrix, the hollow particle has a relatively low density, and after the aluminum ash hollow sphere is combined with the aluminum matrix, a light product can be manufactured; the obtained recycled aluminum ash hollow sphere / aluminum matrix composite foam material has the performance advantages of low density, high specific stiffness, high energy absorption capacity, excellent mechanical and acoustic damping performance and the like, and has a wide application prospect in the fields of aerospace, transportation, national defense and building.

The application discloses a preparation method of a filling bionic double-chiral structure automobile energy absorption box, and relates to the technical field of automobile collision safety. The application further optimizes the scheme of combining the traditional honeycomb structure with the chiral structure, realizes the bionic optimization design of the double-chiral structure and applies the bionic optimization design to the field of the automobile energy absorption box, and three bionic optimization structures combining the double-chiral features are established. It is proved through experiments that the synergistic effect of the honeycomb and the double-chiral unit can effectively reduce the peak force of the energy absorption box in the initial stage of the collision, and the specific energy absorption is significantly improved. Under the action of the impact load, the structure exhibits a more stable and controllable deformation mode, and the instability phenomenon of the traditional energy absorption structure is avoided, so that an optimized solution is provided for the automobile collision safety protection.

This invention relates to a three-dimensional multi-cell structure with adjustable Poisson's ratio and specific energy absorption, and its fabrication method. The three-dimensional multi-cell structure is composed of multiple three-dimensional unit cells arranged periodically in a three-dimensional spatial coordinate system. The three-dimensional unit cells are formed by expanding two-dimensional unit cells through a first spatial transformation or a second spatial transformation. Each two-dimensional unit cell includes two quarter-concave hexagonal structures and a diagonal connecting rod. The two ends of the diagonal connecting rod are connected to a quarter-concave hexagonal structure, and the two quarter-concave hexagonal structures are symmetrical about the centroid of the diagonal connecting rod. This invention, by synergistically adjusting the geometric parameters constituting the unit cell, can flexibly control the negative Poisson's ratio and specific energy absorption of the structure on a macroscopic scale within a wide range, thereby achieving proactive design and optimization of the material's mechanical properties to meet the differentiated requirements for deformation behavior and energy absorption characteristics in different engineering scenarios.

The invention relates to a double-layer multi-cell energy absorption thin-walled tube with a pre-folded outer wall. The double-layer multi-cell energy absorption thin-wall pipe comprises a thin-wall inner pipe, a thin-wall outer pipe and an inner rib plate which are arranged in a nested mode. The thin-wall inner pipe and the thin-wall outer pipe are repeatedly connected in the axial direction of the pipe through N layers of unit cell structures. Each layer of unit cell structure comprises a double-layer thin-wall outer tube and an inner square tube which is connected up and down, and an inner rib plate structure which forms an included angle is connected between the vertical center line of each side wall of the inner square tube and the double-layer thin-wall outer tube; the double-layer thin-wall outer pipe comprises a first unit wall plate and a second unit wall plate which are symmetrical in the circumferential direction of the thin-wall pipe. The first unit wall plate is defined by a double-layer first trapezoidal wall plate and double-layer parallelogram wall plates arranged on the two sides of the first trapezoidal wall plate, the second unit wall plate is a double-layer second trapezoidal wall plate arranged between the first unit wall plates, and the double-layer thin-wall outer pipe is formed by pre-folding a plurality of peak creases and valley creases. Compared with an existing thin-walled tube, the double-layer multi-cell energy absorption thin-walled tube has the advantages that the specific energy absorption is more obviously improved, the compression resistance advantage is obvious, and the application range is wider.

This invention discloses a bridge collision buffer energy-absorbing structure, its processing method, and bridge collision protection facilities. The bridge collision buffer energy-absorbing structure includes a main buffer unit, secondary bridge-shaped load-bearing units, and a vertical connecting strip arranged in a two-dimensional periodic array. The main buffer unit and the secondary bridge-shaped load-bearing units are alternately connected vertically to form the main buffer strip. The vertical connecting strip is alternately connected to the main buffer strip horizontally. The main buffer unit includes a square main buffer platform at the top, with a first inclined sidewall extending downwards connected to the edge of the main buffer platform. The secondary bridge-shaped load-bearing unit includes a square bridging platform at the top, with a second inclined sidewall extending downwards connected to the two horizontal edges of the bridging platform. The lower edges of the first and second inclined sidewalls are collinear with the two sides of the vertical connecting strip. This invention has the advantages of high specific energy absorption, adjustable stiffness, and predictable deformation mode, and can effectively meet the collision protection requirements of bridges of different sizes.

The invention relates to a double-layer pyramid interlayer energy absorption structure for an automobile, and relates to the field of automobile passive safety protection. Comprising an interlayer panel and a sandwich, the sandwich panel and the sandwich core adopt epoxy resin as an adhesive; the interlayer panel is made of a carbon fiber reinforced composite material and comprises four layers of carbon fiber plates, each layer of carbon fiber plate is formed by laying three layers of carbon fiber layers, the thickness of each layer of carbon fiber plate is the same, and the laying angle of each layer of carbon fiber plate can be freely designed. The sandwich structure is low in initial peak force, excellent in energy absorption performance and stable in deformation mode, the defects of a traditional sandwich structure in the aspects of specific energy absorption, light weight level, total energy absorption capacity and deformation stability are overcome, and therefore impact damage to passengers is reduced to the maximum extent when a vehicle collides.

The application provides a kind of composite armor of bionic structure and its preparation method, including sequentially superimposed bulletproof layer, transition layer and energy absorption layer, bulletproof layer includes titanium alloy panel and a plurality of ceramic hemispheres, adhesive and low surface density high performance fiber woven fabric or prepreg are used between the two to bond.The application simulates the macro-micro organization framework of the nacre layer of shell, so that the composite armor has the characteristics of high specific energy absorption, can resist multiple high-speed impacts, the hemispherical convex structure of titanium alloy panel can effectively protect multiple bullet types, each independent ceramic hemisphere does not affect each other, high-hardness ceramic hemisphere can blunt and grind the projectile, the cambered surface design of bulletproof layer can change the penetration direction of the projectile, the ceramic hemisphere can make the failure mode deflect between layers, greatly improving the multi-hit bullet performance of the armor plate.

The application discloses a new energy automobile snowflake-imitating hierarchical multi-cell thin-walled energy-absorbing pipe structure, which comprises a first multi-cell thin-walled energy-absorbing pipe structure, wherein the first multi-cell thin-walled energy-absorbing pipe structure comprises an outer thin-walled pipe and an inner multi-cell thin-walled energy-absorbing structure arranged in the outer thin-walled pipe; the inner multi-cell thin-walled energy-absorbing structure comprises a plurality of arranged single-cell thin-walled energy-absorbing structures; each single-cell thin-walled energy-absorbing structure comprises a hollow small regular hexagonal prism, a large regular hexagonal prism and a connecting rib plate; the central axis of the large regular hexagonal prism and the small regular hexagonal prism is coincident, the side surfaces of the large regular hexagonal prism and the small regular hexagonal prism correspond to each other and are parallel; the connecting rib plate is connected between the corresponding side edges of the large regular hexagonal prism and the small regular hexagonal prism; and each side surface of the large regular hexagonal prism is provided with an inwardly recessed groove. The snowflake-imitating hierarchical multi-cell thin-walled energy-absorbing pipe structure has the advantages of high specific energy absorption, high pressure crushing force efficiency and good deformation mode and can meet the anti-collision requirements of new energy automobiles.

The application discloses a steel-carbon fiber hybrid anti-climbing energy absorption optimization method for a track vehicle filling dot array, and comprises the following steps: establishing a finite element model of an anti-climbing energy absorption device of a track vehicle and setting design variables of a dot array energy absorption structure, generating HQLS dot array energy absorption structure samples in the range of the design variables by adopting a full factor method combined with a Latin hypercube sampling method, and generating response indexes of each sample by finite element simulation calculation; adopting a moving least square method to construct a mechanical property surrogate model, adopting a global adaptive response surface method to perform global optimization on the surrogate model, and obtaining an optimal balance solution of specific energy absorption and average crushing force based on a Pareto front, generating optimal design variables, and substituting the optimal design variables into the finite element model to verify errors; if the errors meet a preset accuracy, optimal parameters are output, otherwise, iteration is updated. The anti-climbing energy absorption optimization method can perform global optimization on the geometry and material configuration of the anti-climbing energy absorption structure of the track vehicle under the conditions of multiple parameters and multiple targets.

The application discloses a chiral concave octagonal superstructure with high specific energy absorption and indentation resistance, which is a grid structure formed by repeatedly arraying and stacking a plurality of cell structures; the cell structure is obtained by twice rotating array and three times mirror imaging of a two-dimensional negative Poisson's ratio structure unit; the two-dimensional chiral concave octagonal negative Poisson's ratio structure unit is a concave octagon, and different scale chiral concave negative Poisson's ratio grid structures can be obtained by arraying the cell structure; the structure simultaneously has chiral characteristics and a concave octagonal structure in the configuration of the cell; after the mirror imaging operation, new concave polygonal structures are formed between the cells, the overall negative Poisson's ratio effect of the grid structure is enhanced, and the rotation of the chiral structure around the node during the stress process of the grid structure further promotes the enhancement of the negative Poisson's ratio effect.

The invention relates to the technical field of structural plates, and discloses an anti-explosion and anti-impact sandwich structural plate with 3D printing honeycombs and round tubes as cores, the anti-explosion and anti-impact sandwich structural plate comprises a base, a panel is fixedly connected to the right side of base equipment, and an anti-explosion and anti-impact assembly is arranged in the panel and used for improving the anti-explosion and anti-impact performance of the sandwich structural plate; the anti-explosion and anti-impact assembly comprises an adhesive film body, the adhesive film body is fixedly connected to the interior of the panel, a honeycomb core material is arranged in the adhesive film body, and round steel pipes are evenly and fixedly connected to the interior of the honeycomb core material. The inner core adopts the 3D printed honeycomb and circular tube, and the honeycomb and circular tube can increase the crushing force efficiency and enable the energy absorption curve transition section to be smoother at the same time; the bearing capacity and energy absorption capacity of the circular pipes can be improved through lateral restraint of the honeycombs on the circular pipes, and the circular pipes and the honeycombs work cooperatively to form a combination of bearing capacity addition of the circular pipes, so that the specific energy absorption of the sandwich structural plate is improved, and the bearing capacity of the sandwich structural plate is far beyond that of a conventional sandwich structural plate.

The invention discloses a paper-cut-origami synergistic metamaterial capable of resisting impact in multiple directions. The metamaterial is formed by combining a regular octahedron paper-cut structure and a Kresling origami structure. In the compression process, the buckling of the paper folding panel is promoted by utilizing the boundary constraint of the octahedral paper-cut structure, so that the energy absorption efficiency is improved. Compared with a traditional anti-chiral Kresling origami metamaterial, the structure has a higher specific energy absorption characteristic. In addition, the geometric composition of the structure has rotation periodicity, and the structure shows good multi-directional mechanical property consistency and rigidity adjustability under quasi-static compression load. The invention can solve the problem that the existing metamaterial is difficult to realize stable and controllable mechanical properties in a plurality of main bearing directions, and obviously improves the energy absorption efficiency of the structure under the condition of large deformation.

The invention discloses a corrugated sandwich bidirectional energy absorption structure and a design method. The corrugated sandwich bidirectional energy absorption structure comprises a unit composed of periodic corrugated curved walls and a sandwich body composed of an upper panel and a lower panel. Controllable buckling and multi-stage collapsing of the corrugated wall plate in the loading process are achieved through preset curvature, a node transition structure and wall thickness distribution. Independent but mutually coupled energy dissipation paths are formed in the units in the two main directions, so that the structure can keep a stable energy absorption mode under the working conditions of compression, shearing and composite impact; according to the structure, a partition triggering mechanism, local plastic hinge control and a shape constraint effect are introduced in design, specific energy absorption, platform stress stability and structure failure resistance are remarkably improved, the structure can be widely applied to traffic equipment collision prevention, aerospace protection, electromechanical equipment buffering, building disaster reduction and other scenes, and light weight and efficient energy absorption are both achieved.

The invention discloses a replaceable medical helmet inner pad of a subarea gradient negative Poisson's ratio structure and an optimization method of the replaceable medical helmet inner pad, and belongs to the technical field of medical instruments and rehabilitation protection. The problems that an existing medical helmet is not targeted in energy management, limited in rotation response inhibition, poor in comfort, high in replacement and adaptation cost, long in optimization design period and slow in convergence are solved. Wherein the helmet inner pad is of a subarea gradually-changed negative Poisson's ratio sandwich structure and comprises an upper spreading layer, a middle negative Poisson's ratio unit layer and a lower sliding layer, and individualized adaptation is achieved through a replaceable splicing piece module; according to the optimization method, a design optimization closed loop is formed by combining parameterized design, a multi-modal agent model and trust region multi-target Bayesian optimization. According to the invention, the head injury index and the peak angular velocity are reduced in a short stroke, the specific energy absorption is improved, and meanwhile, the lightweight, the comfort and the maintainability are considered.

This invention belongs to the field of impact protection technology and relates to a double-layer thin-walled impact-resistant protective structure composed of triangular pyramidal units. This structure consists of multiple bottomless triangular pyramidal units that are alternately assembled to form a strip-like structure, which is then connected end-to-end to form a cylindrical double-layer thin-walled structure. The geometric dimensions are determined by the number of triangular pyramidal units used, which must be even and no less than six. This structure utilizes the low out-of-plane buckling stiffness of the oblique triangular facets to form a stable progressive deformation mode during axial crushing, thereby achieving high specific energy absorption capacity and low initial peak load. This structure, arranged in an array, serves as the core layer and is combined with a polyethylene non-woven fabric panel to form a "sandwich" composite protective structure. It can be used in protective equipment such as individual body armor, providing comprehensive protection against both ballistic and blunt force trauma, effectively reducing blunt force trauma damage caused by projectile impacts.

The application discloses a woodpecker beak inspired energy absorption box, and the unit body of the inner core comprises a torsion-resistant circular tube and an anti-oblique impact tube; a plurality of the torsion-resistant circular tubes are arranged in a square shape, and a semicircular tube is arranged in the gap between each adjacent two of the torsion-resistant circular tubes closest to the anti-oblique impact tube and the anti-oblique impact tube; the anti-oblique impact tube is composed of an inclined connecting structure, a bird feather imitating three-axis plate and a bird feather imitating single-axis plate; the inclined side of the inclined connecting structure is fixed to the outer side of the bird feather imitating three-axis plate or the bird feather imitating single-axis plate; and the inclined connecting structure of the unit body one is embedded into the corresponding inclined connecting structure of the adjacent unit body two. The inclined connecting structure of the anti-oblique impact tube disperses the oblique impact force and reduces the axial impact force, the bird feather imitating three-axis plate and the bird feather imitating single-axis plate have high elastic modulus, compressive strength and specific energy absorption; and the torsion-resistant tube improves the torsion resistance, cooperates with the circular tube and the semicircular tube to trigger a high-order buckling mode, and achieves higher energy absorption effect.

The invention relates to a design method of a different-size mixed TPMS (Tire Pressure Monitor System)-based lattice structure for additive manufacturing, and belongs to the field of computer-aided structural design and additive manufacturing. A preset regular hexahedron three-dimensional space is divided twice, a total weight field function is calculated, a mixed curved surface is obtained, coordinates in the obtained curved surface are subjected to rotation transformation and three-time symmetric operation, and the obtained curved surface is subjected to thickening operation. The method has the advantages that the freedom of TPMS-based structural unit cell design is increased, the convenience and rapidity of the design method are greatly improved through a single weight fusion mode, the mechanical property, Young modulus, yield strength and specific energy absorption of structural unit cells can be continuously adjusted through changes of rotation parameters, and compared with an initial TPMS structure, the Young modulus, yield strength and specific energy absorption are obviously improved; the method is very suitable for subsequent implicit function control generation and expansion of the modular mechanical metamaterial, can realize large-range rapid modeling generation of the modular mechanical metamaterial, and provides a new thought for TPMS-based structure innovation.

The invention discloses a design method of a pressure-resistant and impact-resistant soft and hard double-phase composite structure. The method comprises the following steps: determining geometric design parameters of a soft and hard double-phase composite unit cell structure; selecting a matched hard and soft phase matrix material, and determining material parameters; calculating an equivalent elastic modulus under the action of the impact load according to a cooperative deformation and energy dissipation mechanism; selecting a soft-hard double-phase composite multi-cell structure with multiple groups of geometric parameters to carry out finite element modeling calculation, simulating a load displacement relationship under a quasi-static compression test, and preselecting a group with the optimal bearing capacity; obtaining an equivalent stress strain relation according to the load displacement relation; the relationship between energy absorption and strain is obtained according to the equivalent stress-strain relationship, and the specific energy absorption of the soft and hard dual-phase composite unit cell structure is obtained through calculation; the effective elastic modulus and the specific energy absorption of the soft and hard double-phase composite unit cell structure are used as evaluation indexes, and geometric design parameters are adjusted to meet the design requirements of bearing and impact resistance. The soft and hard double-phase composite structure with the bearing capacity and the anti-impact capacity meeting the design requirements can be designed.

The application provides a design method of a novel foam aluminum filled origami sandwich structure, inspired by ancient architectural structures or biological structures in nature, and based on origami art, a novel foam aluminum filled origami sandwich structure, such as a pyramid-like origami structure, is invented. The novel foam aluminum filled origami sandwich structure is further filled with foam aluminum in the origami structure, while the energy absorption capacity of the novel origami sandwich structure is improved, and the lightweight advantage is maintained. The novel structure has the characteristics of low initial peak force, high platform force, high load efficiency, high specific energy absorption capacity, and the like, and is a composite structure with good impact resistance and high energy consumption.

The application provides an ultra-low-altitude umbrella-free air-drop device, which comprises a platform, a supporting arm and a foot pad, the platform and the supporting arm are connected through a hinge, and the hinge connection parts of the platform and the supporting arm are respectively provided with a supporting arm driving mechanism and a supporting arm unfolding locking mechanism; the supporting arm is composed of three energy-absorbing modules, the energy-absorbing modules are connected through hinge joints, are mutually parallel and are stacked, the connection parts are provided with a joint driving mechanism and a joint unfolding locking mechanism; the supporting arm is connected with a movable rod of the hinge and can move along the rotating direction of the hinge after the electromagnetic lock is unlocked. The ultra-low-altitude umbrella-free air-drop device has a light overall structure, the carbon fiber material used has small density and high strength, and is convenient to carry; the aluminum honeycomb energy-absorbing material used has small density, large specific energy absorption, and better buffering performance compared with most existing energy-absorbing materials, can effectively absorb the impact of heavy equipment air-drop, and meets the high-structural-integrity requirement of umbrella-free air-drop of heavy equipment.

The invention discloses a steel-carbon fiber hybrid anti-creeping energy absorption optimization method for a railway vehicle filling dot matrix, and the method comprises the steps: building a finite element model of a railway vehicle anti-creeping energy absorption device, setting a design variable of a dot matrix energy absorption structure, and employing a full-factor method in combination with a Latin hypercube sampling method, hQLS lattice energy absorption structure samples are generated within the design variable range, and response indexes of the samples are generated through finite element simulation calculation; constructing a mechanical property agent model by adopting a moving least square method, performing global optimization on the agent model by adopting a global adaptive response surface method, obtaining an optimal equilibrium solution of specific energy absorption and average crushing force based on a Pareto front, generating an optimal design variable, and substituting the optimal design variable into a finite element model to verify an error; and if the preset precision is met, outputting the optimal parameter, otherwise, performing iterative updating. According to the anti-creeping energy absorption optimization method, global optimization can be carried out on geometry and material configuration of the anti-creeping energy absorption structure of the railway vehicle under the multi-parameter and multi-target conditions.