37 results about "Geometric stability" patented technology

A three-dimensional composite reinforcement, a three-dimensionally reinforced multifunctional nanocomposite, and methods of manufacture of each are disclosed. The three dimensional reinforcement comprises a two dimensional fiber cloth upon which carbon nanotubes have been grown, approximately perpendicular to the plane of the fiber cloth. The nanocomposite comprises the three-dimensional reinforcement and a surrounding matrix material. Examples illustrate improvements in the through-thickness mechanical, thermal, and electrical properties of the nanocomposite, in addition to substantial improvements in geometrical stability upon temperature changes and vibrational damping, compared to baseline composites reinforced with the two-dimensional fiber cloth alone. Embodiments of the nanocomposite may also be configured to perform multiple functions simultaneously, such as bearing a thermal or mechanical load simultaneously or bearing a mechanical load while also monitoring the state of damage within the nanocomposite.

The diffusion beads according to the present invention have a core-shell structure of multi-layered beads consisting of organic and inorganic materials. The diffusion beads are used for improving functions of conventional organic and inorganic polymer diffusion beads. The structure according to the present invention no only enhances light scattering characteristics of the diffusion beads, but also strengthens the thermal stability and geometric stability thereof.

A thermoplastic filament comprising multiple polymers of differing flow temperatures in a geometric arrangement and an interior channel containing a structural or functional thread therein is described. A method for producing such a filament is also described. Because of the difference in flow temperatures, there exists a temperature range at which one polymer is mechanically stable while the other is flowable. This property is extremely useful for creating thermoplastic monofilament feedstock for three-dimensionally printed parts, wherein the mechanically stable polymer enables geometric stability while the flowable polymer can fill gaps and provide strong bonding and homogenization between deposited material lines and layers. These multimaterial filaments can be produced via thermal drawing from a thermoplastic preform, which itself can be three-dimensionally printed. Furthermore, the preform can be printed with precisely controlled and complex geometries, enabling the creation of a filament or fiber with an interior thread contained within the outer, printed filament or fiber. This thread adds structural reinforcement or functional properties, such as electrical conductivity or optical waveguiding, to the filament.

The invention discloses a powder metallurgy bearing material. The powder metallurgy bearing material is characterized by being composed of, by weight, 5.2-5.5 parts of tungsten, 2.1-2.3 parts of cobalt, 5.7-5.9 parts of nickel, 1.2-1.5 parts of titanium, 0.2-0.5 part of boron, 72-75 parts of ferrum, 3.2-3.5 parts of silicon, 1.2-1.4 parts of graphite, 1.7-1.9 parts of manganese, 5.2-5.6 parts of chromium, 2.3-2.5 parts of zinc stearate, 1.2-1.4 parts of microcrystalline wax, 0.4-0.5 part of tungsten carbide, 0.2-0.4 part of titanium carbide and 1-2 parts of auxiliary agents. The graphite is added to raw materials of the powder metallurgy bearing material, so that abrasion resistance and lubricity of a bearing are enhanced, and the bearing made of the powder metallurgy bearing material is compact in structure and good in microstructure, has very few holes, and has excellent structural rigidity, hardness, fatigue resistance and tensile strength; addition of the nickel enhances toughness and the elasticity modulus of alloy, thereby playing a prominent role in guaranteeing geometric stability of the bearing.

The invention discloses a compression bar contact type tensegrity structure and an integration and tension exertion method, and relates to the technical field of engineering structure. The compressionbar contact type tensegrity structure comprises stiffening ring triangular trusses, core shaft triangular trusses and longitudinal pulling rods. The stiffening ring triangular trusses are pressed inan isolation mode; the core shaft triangular trusses bear pressure in a contact mode; and the longitudinal pulling rods are constantly pulled, and a plurality of paralleled outer rings of the stiffening ring triangular trusses in the heat-to-tail sequence and are closed to tails. The compression bar contact type tensegrity structure is a self-balance and self-bearing structure, segmented assemblage is adopted, the compression bar contact type tensegrity structure symmetrically extends, modules are integrated in an assembly mode, the longitudinal pulling rods are enabled to exert uniform tension through the graded and symmetric synchronized push of ends of the core shaft triangular trusses. The compression bar contact type tensegrity structure and the integration and tension exertion methodhave the characteristics of light weight, high stiffness, high geometric stability, and high practicability; the installation integration method is simple, convenient and safe, and has a high expandability; and the tension exertion method is effective, the tension exertion equipment is less, control is easy, the tension is uniform and precise, and the structural joint is simple and neat.

The invention discloses a multi-face cascadable steering engine with a position feedback center output shaft. The multi-face cascadable steering engine comprises a steering engine body and a motor. The steering engine body comprises a top shell, a gear shell and a lower shell. The lower shell is provided with a bottom outer shell connector. The motor is fixedly arranged in the gear shell. The output shaft is arranged at the central position of the gear shell, and is further provided with a reduction gear set. A rotation sensor which is in engaged linkage with the reduction gear set is further arranged in the gear shell. The top of the output shaft is connected with an output shaft connector, and connecting grooves of the same size are formed in the central position of the output shaft connector and the central position of the bottom outer shell connector. The output shaft connector can be in cascade connection with a bottom outer shell connector of the next steering engine through a quick-dismounting connecting piece, and meanwhile can be in cascade connection with the side face of the next steering engine through an angle connector. The structure is simple and geometric stability is good.

The invention belongs to the technical field of devices combining antenna components with antennas, and discloses a novel double-layer scissor parabolic cylindrical expandable truss antenna device, which is composed of a plurality of double-layer scissor hinge mechanisms, wherein adjacent double-layer scissor hinge mechanisms are connected to each other by a double-headed hinge, a sliding hinge, athree-headed hinge and a four-headed hinge to form a closed parabolic cylinder; each double-layer scissor hinge mechanism consists of two vertical rods, two long inclined rods, two short inclined rods, four double-headed hinges, four sliding hinges, and two springs; and adjacent two double-layer scissor hinges share a vertical rod, a double-headed hinge or a three-headed hinge or a four-headed hinge, a sliding hinge, and a spring. The invention has high geometric stability, strong rigidity, simple movement mechanism and control system, small volume after closing, high storage rate, strong module expansion, as well as simple assembly, and may be respectively deployed in the axial or length direction, thereby satisfying the requirements for the use of aperture antennas.

The invention relates to a gob-side entry retaining roadside support system and a construction method thereof. A rhombic steel bar net is arranged on one side of a gob, an air drum cloth is laid on the inner side of the rhombic steel bar net, light aggregate concrete is adopted to perform guniting treatment on the air drum cloth and the rhombic steel bar net, a windtight light aggregate concrete spray layer is formed on the side of the gob, the thickness of the light aggregate concrete spray layer is 200-500 mm, and the other side of the light aggregate concrete spray layer is close to a steel tube concrete pier stud supporting device. A steel tube concrete pier stud is formed by filling an empty steel tube with concrete; through a restraint effect of a steel tube casing, internal concrete is in a three-dimensional stressed state, the geometrical stability of the steel tube wall is enhanced, and the bearing capacity of the steel tube concrete pier stud is improved. According to the gob-side entry retaining roadside support system, a top plate can be supported in high strength, coal mining efficiency is effectively improved, and an operation environment in a roadway is improved; the steel tube concrete pier stud can be recycled through a special thrust device, and the roadway retained cost is reduced.

The invention relates to a three-dimensional reconstruction method in the field of computer vision, and particularly relates to an on-line tracking and dense reconstruction method, an on-line trackingand dense reconstruction system and on-line tracking and dense reconstruction equipment on mobile equipment. The invention aims to realize the on-line dense three-dimensional reconstruction on the mobile equipment. The three-dimensional reconstruction method comprises the following steps: acquiring a current depth image of a frame, calculating a three-dimensional point and a normal vector of eachpixel point under a camera coordinate system, and calculating a depth noise standard deviation and a gradient graph; selecting a point pair capable of providing enough constraint for an ICP algorithmbased on a geometric stability sampling method, and adopting a visual tracking and IMU information fusion method based on an ICP covariance matrix condition number; after calculating the posture of acamera, fusing a depth map into a TSDF model; carrying out light projection on fused volume data at the calculated posture of the camera so as to obtain a surface point cloud. The method is high in robustness and fast in calculation speed. Meanwhile, based on the method, a finally obtained three-dimensional model is reasonable and reliable.

The invention discloses a spring-driven space deployable annular antenna device. The spring-driven space deployable annular antenna device comprises n sets of triangular deployable assemblies and an equilateral right triangle deployable unit A; the equilateral right triangle deployable unit A is composed of n sets of triangular deployable cooperative assemblies connected below the n sets of adjacent triangular deployable assemblies; n is greater than or equal to 2; the n sets of triangular deployable assemblies are connected end to end through four-head hinges; the n sets of triangular deployable cooperative assemblies and the n sets of triangular deployable assemblies share the same set of transverse rods connected through the four-head hinges; the n sets of triangular deployable assemblies and the n sets of triangular deployable cooperative assemblies are connected end to end; and, under the action of the elasticity of a spring, folding or unfolding is carried out, so that the deployable annular antenna device is formed. The device has relatively high geometric stability; a motion mechanism and a control system are simple; after being folded, the device is small in volume and high in accepting rate; an active driving device is unnecessary; the module extensibility is high; accessories are simple; and use requirements of large-aperture space antennas, such as communication satellites and space exploration, can be satisfied.

The invention provides a rotomolding-grade polyethylene filled modified composite material and a preparation method thereof. The rotomolding-grade polyethylene filled modified composite material comprises, by weight, 25 to 90 parts of LLDPE1, 0 to 40 parts of LLDPE2, 10 to 50 parts of an inorganic filling material, 1 to 6 parts of a compatibilizing agent, 0.5 to 10 parts of a toughening agent, 0.1to 1 part of an antioxidant and 0.2 to 0.6 part of a lubricant, wherein the LLDPE1 and the LLDPE2 are two LLDPE materials with different performances; the inorganic filling material contains glass beads; and the compatibilizing agent is PE grafted maleic anhydride. The preparation method comprises the following steps: with linear low-density polyethylene resin as a matrix, filling the linear low-density polyethylene resin with the inorganic filling material, adding POE-g-GMA, POE-g-MAH and the like, and carrying out blending, granulation and grinding so as to prepare a rotomolding material. According to the invention, a rotomolded product prepared from the rotomolding material is improved in strength and has good wear resistance, acid and alkali resistance, geometric stability and antibacterial properties; in addition, the cost of production can be reduced.

A reinforcement means for moulded and extruded articles such as tires has a metal structure with a layer of silica gel bonded thereto. The silica gel bonds the reinforcement means to the rubber compound during the moulding/vulcanisation of the rubber compound without the need for a slow curing stage. The silica gel may be applied to the metal structure by a sol-gel process with the gel formed by drying the sol at a temperature up to 150° C. The reinforcement means is preferably a cable formed from steel wires coated with the silica gel. To further improve bonding of the silica gel to the rubber compound, an organosilane bonding agent may be included in the rubber compound or the reinforcing means provided with a second layer comprising an organosilane as a bonding agent. The reinforcement means are particularly useful for strengthening and providing geometric stability to tires.

The invention discloses industrial warp-knitted base fabric of high intensity, large size and good stability. The geometric base fabric with good stability and high strength is knitted from false-twisted yarn and fully-drawn yarn which is made of polyolefin or/and polyphenylene sulfide. The Japanese industrial standard (JIS) L1018 8.14.2 constant load elongation rate test proves that the industrial warp-knitted base fabric has the elongation rate of less than 5 percent; the JIS L10188.13 tensile strength and elongation rate test proves that the industrial warp-knitted base fabric has the tensile strength of 400-1200 N; and the industrial warp-knitted base fabric has the gram weight of 40-500 g/m<2>. To achieve the better geometric stability performance of the base fabric, at least two combs are used for knitting the base fabric, wherein the front comb is used for circularly-knitting, and at least one of the rear combs is used for weft-knitting.

The invention provides an H-shaped steel and concrete composite pile and a construction method thereof. The H-shaped steel and concrete composite pile is characterized by comprising an H-shaped steel and two channel steels fixed in openings on two sides of the H-shaped steel and with opposite notches; closed steel plates are arranged in the notches of the two channel steels; and concrete is poured in cavities formed by the notches of the two channel steels and the closed steel plates. The H-shaped steel and concrete composite pile is simple and practical in structural design, fully combines respective advantages of the steels and the concrete materials, reduces self weight through use of the steels, and improves horizontal bearing capacity; meanwhile, as the concrete is filled in the steel pile, on the one hand, the geometric stability of the inner wall of the H-shaped steel can be enhanced to delay or prevent local buckling so as to improve the bearing capacity; and on the other hand, because of restraint of the steels to the concrete, the concrete is located in a three-way stress strain state, the generation and the development of longitudinal micro cracks are delayed, and the compressive strength and the compressive deformation capacity are improved.

An underground cavern excavation support system includes a top arch excavation area, an end wall excavation area and an inverted arch excavation area which are sequentially connected from top to bottom. The top arch excavation area is provided with a finalized operation platform, and anchor rods are arranged outside the top arch excavation area and the end wall excavation area. The top arch excavation area is also provided with a drainage body. Two symmetrically arranged water and electricity prefabricated boxes are arranged in the inverted arch excavation area. Each water and electricity prefabricated box is provided with a hydroelectric isolation panel dividing the water and electricity prefabricated box into an upper part and a lower part, wherein the upper part of the water and electricity prefabricated box is provided with an electric line pipe gallery, and the lower part of the water and electricity prefabricated box is provided with an underground drainage pipe gallery. Comparedwith the prior art, excavation area blocks on two sides form an obtuse angle, which is beneficial to the geometric stability during the whole excavation process. Support conducted after complete excavation of the whole block is not required, the periphery is excavated and supported first, and then the middle area is excavated. The excavation and support construction efficiency is improved.

The invention is intended to provide a modified polyformaldehyde material to improve contractibility of polyformaldehyde material and a preparation method thereof. Polyformaldehyde is a high-density high-crystallinity linear polymer with no side chains which has good integrated performance, as well as excellent wear resistance and self-lubricating property, good oil resistance and good peroxide resistance. Polyformaldehyde is a tough elastic material which has good creep resistance, good geometric stability and good impact resistance even at low temperature. However, polyformaldehyde is a crystallizable material and rarely absorbs moisture. High crystallization degree of polyformaldehyde leads to a high shrinkage, up to 2-3.5%, which is different to different reinforcing materials. Therefore, shrinkage of polyformaldehyde is improved through glass fiber reinforcement. Shrinkage stability of the polyformaldehyde material can be evidently improved.