2103 results about "Central symmetry" patented technology

An adaptive optical lens device, system and method of using the same is composed of at least two planar substrates and at least one homogeneous nematic liquid crystal (LC) layer. One planar substrate has a spherical or annular ring-shaped Fresnel grooved transparent electrode within it, the other has a transparent electrode coated on its inner surface. The thickness of the LC layer is uniform. When a voltage is applied across the LC layer, a centro-symmetrical gradient distribution of refractive index within LC layer will occur. Therefore, the LC layer causes light to focus. By controlling the applied voltage, the focal length of the lens is continuously tunable.

The present invention is a method for exploring the viewpoint and focal length of a fisheye lens camera (FELC). It employs the characteristic of the central symmetry of the distortion of the fisheye lens (FEL) to set its optic axis by means of a calibration target with a plurality of symmetrically homocentric figures. Once the optic axis is fixed, further disclose the viewpoint (VP) of the FELC along the optic axis through a trail-and-error procedure and calculate its effective focal length and classify it to the primitive projection mode. Because the invention is capable of finding out both the internal and external parameters of the FELC and the calibration method is easy, low-cost, suitable to any projection model, and has greater sensitivity corresponding to an increasing in image distortion, the distortive images can be transformed easily to normal ones which fit in with a central perspective mechanism. Furthermore, the invention is also practicable and excellent in its applications in the fields of quality identification of the FEL and wide-view 3-D metering.

Disclosed are apparatus and methods for measuring a characteristic, such as overlay, of a semiconductor target. In general, order-selected imaging and / or illumination is performed while collecting an image from a target using a metrology system. In one implementation, tunable spatial modulation is provided only in the imaging path of the system. In other implementations, tunable spatial modulation is provided in both the illumination and imaging paths of the system. In a specific implementation, tunable spatial modulation is used to image side-by-side gratings with diffraction orders ±n. The side-by-side gratings may be in different layers or the same layer of a semiconductor wafer. The overlay between the structures is typically found by measuring the distance between centers symmetry of the gratings. In this embodiment, only orders ±n for a given choice of n (where n is an integer and not equal to zero) are selected, and the gratings are only imaged with these diffraction orders.

The invention relates to a multistation material transmission manipulator which is characterized in that the manipulator is used for a rotary sealing ring framework punching forming technique and mainly comprises a big template, a swing mechanism, a lifting mechanism, six finger mechanisms and two electromagnetic chucks, wherein the big template is round; the swing mechanism and the lifting mechanism are arranged at the center of the big template; 10 positioning slots are distributed on the periphery of the big template; the six finger mechanisms and the two electromagnetic chucks are divided into two groups, uniformly arranged on the swing mechanism in a radial shape and central symmetrical mode and are corresponding to the position of the positioning slot; and the finger mechanisms and the electromagnetic chucks are all arranged on the top of a rotary disc of the swing mechanism. The manipulator can automatically and continously finish the material transmission and carrying operation (among three working stations of stretching, reverse-drawing and punching) in the punching forming process of the rotary sealing ring framework.

A plate board type MIMO (multiple-input multiple-output) array antenna including a board, a plurality of antenna elements manufactured on the board, and an isolation unit offsetting effects of electromagnetic waves radiated from the plurality of antenna elements on the other antenna elements of the plurality of antenna elements. In a case where two antenna elements are used, the isolation unit may include at least one isolation element positioned within a space between the two antenna elements on the board and symmetric with respect to a center of a distance between the two antenna elements.

A sun tracking system includes a first, and a second photo sensors, separately mounted on a solar panel on two positions apart from one another and symmetrical with respect to a center of the panel. A first sleeve surrounds the first photosensor; a second sleeve surrounds the second photosensor. Each of the sleeves has an inclined opening with reference to the surface of the panel.

The vertical dual-shaft four-cylinder electrohydraulic servo testing machine comprises: a hydraulic pressure drive for dual-direction stress filed, a four-cylinder drive fit to any loading path, a differential close-loop servo system, a function generator fit to different waves, a position transfer device fit to assemble the test piece, a guide plate and linear rail to ensure co-shaft and avoid bending. This invention is very convenient.

The invention discloses a polarized reconfigurable magneto-electric dipole antenna, comprising a square upper PCB board, a square lower PCB board, a feed port and four antenna units. The four antenna units are arranged on the diagonals of the upper PCB board in a central symmetry mode. The lower PCB board comprises a square substrate integrated waveguide resonant cavity and a coupling slot. An inner conductor of the feed port is connected with patches on the upper surface of the lower PCB board. An outer conductor is connected with the patches on the lower surface of the lower PCB board. The polarized reconfigurable magneto-electric dipole antenna provided by the invention has the advantages of simple structure, low loss, wide bandwidth, high gain, high radiation efficiency and convenient switch among three polarized states. The polarized reconfigurable magneto-electric dipole antenna is very applicable to a modern wireless communication system, especially a 5G-band WiFi system.

The invention discloses a safe self-destroying medical injector, which comprises the following parts: hollow cylinder, snap coil, needle seat and core bar, wherein the plug is assembled in the core bar head; a coil of flute is set in the head of cylinder; the boss is set on the top of core bar with upper round boss and lower round boss under the boss; the easy-breakpoint is set under the lower round boss; the needle seat is composed of separable conical seat and support seat with an 'O' rubber ring between the excircle of conical seat bulk and cylinder; two through-grooves of central symmetry are set under the conical seat, which sets two bosses of central symmetry between two through-grooves; the boss snaps the flute on the cylinder; the flute is set on the inner hole bottom of conical seat.

The invention provides an electric power steering system with an individually adjustable-parameter and curve-type power characteristic. The system is characterized in that: the power characteristic curve is a segmentation curve which is symmetric about the centre of a zero input moment point; an integral curve can be determined by setting 5 key parameter values on the curve, and, when one or more key parameters are regulated, the integrity of the curve and the continuity of the first-order derivative can still be guaranteed without modifying other parameters. The power characteristic of the electric power steering system provided by the invention can change the shape of the curve by adjusting 5 of the key parameter values to achieve different assisting effects, so the electric power steering system has the optimum steering performance which is expected by drivers.

The invention discloses a rivet for friction-self piercing riveting (F-SPR) and an F-SPR connecting system thereof. The rivet comprises a semi-hollow rivet body and a rivet cap, wherein the lower surface of the rivet cap is connected with the semi-hollow rivet body; a wedge-shaped taper corner is arranged at the bottom end of the semi-hollow rivet body; chamfers for assembly and disassembly and a rotating driving structure are arranged on the edge of the upper end of the rivet cap; a locating structure is arranged in the center of the rivet cap; the rotating driving structure is a directed concave surface or a directed convex surface in central symmetry; and the locating structure is a convex surface or a concave surface in central symmetry and mirror symmetry. When the rivet is matched with a driving system for utilization, the driving rigidity and locating accuracy of the rivet during the F-SPR process can be improved, the problems that during the high-speed rotation process of the semi-hollow rivet, the stability is poor and the rivet axis and the rotation axis do not overlap are solved, the probability that a connector loses efficacy is reduced, the problem that a clearance is formed between the rivet and a panel is avoided, and the technological reliability of an F-SPR technology when connecting steel, aluminum, magnesium materials, composites and heterogeneous materials is guaranteed.

An optical filter is disclosed which adjusts the contours of blurred images and maintains the size of blurred images. The optical filter includes a substrate being substantially transparent and a first layer whose optical density changes continuously, formed on the substrate. A transmission rate of the first layer decreases substantially linearly from a center toward a periphery of the optical filter, and the transmission rate distribution is symmetric with respect to the center.

The invention provides a seamless assembly large screen displayed with multi-unit image and an assembly method thereof, belonging to the field of large-screen assembly technique. The large screen is formed by the assembly of a group of display units and is characterized in that the mainbody surface of the surface glass substrate of the display unit is a planar structure; the edge surface of the surface glass substrate is an arc structure of the same specification; arc surfaces of adjacent sides of all display units are symmetric correspondingly to the joint center; each display unit is matched with an image rectifier which is connected with image input data; the seamless assembly large screen displayed with multi-unit image and assembly method thereof utilize non-uniform image density display, optical principle and image distortion rectification technique to eliminate the assembly seam on the large screen; furthermore, as the display units have the same specification and can be mass-produced, the production cost is reduced, the installation is convenient and the quality is stable.

The invention discloses a multifunctional shearing test fixture used for composite material parameter identification. The multifunctional shearing test fixture comprises an upper fixture body and a lower fixture body, wherein the upper fixture body is connected with a loading part of a testing machine; the lower fixture body is connected with a supporting platform of the testing machine; the upper fixture body is the same as the lower fixture body in structure and in central symmetry with the lower fixture body; each of the upper fixture body and the lower fixture body comprises a connecting piece (1), a clamping piece (5) and a clamping mechanism; the connecting pieces (1) are connected with the testing machine and the clamping pieces (5); each clamping piece (5) is divided into an upper part and a lower part; the upper parts are connected with the connecting pieces (1) and an angle limiting mechanism is arranged at the upper part; the lower parts and the clamping mechanisms are jointly used for clamping a test piece; the clamping mechanisms comprise regulating parts and compressing pieces (6); the compressing pieces (6) are connected with the clamping pieces (5) through an adjusting mechanism; a limiting mechanism is arranged on the clamping piece (5) and used for limiting positions of the compressing pieces to enable the compressing pieces to perform movement along set tracks. The multifunctional shearing test fixture has the advantages of being light in weight, simple in operation and easy to dissemble and capable of realizing pure shear, tension-shear and tension-shear combined loading.

The invention discloses a central symmetry type circular pipe positioning device. The central symmetry type circular pipe positioning device comprises a bottom positioning die, an upper pressing die, a left V-shaped block, a right V-shaped block, a levorotation nut slide block, a dextrorotation nut slide block and a two-way lead screw. The upper pressing die is arranged over the bottom positioning die. The left V-shaped block and the right V-shaped block are arranged on the left side and the right side of the bottom positioning die in a symmetrical manner. The levorotation nut slide block is arranged below the left V-shaped block. The dextrorotation nut slide block is arranged below the right V-shaped block. The two-way lead screw penetrates in one end of the levorotation nut slide block and then penetrates out of the other end of the dextrorotation nut slide block. By means of the manner, a circular pipe is positioned and clamped in four directions through the central symmetry type circular pipe positioning device, and the central symmetry type circular pipe positioning device has the beneficial effects of being accurate and reliable in positioning, uniform in clamping force, simple in structure and convenient to manufacture and is suitable for positioning and clamping circular pipes of various diameters.

The invention discloses a double piezoelectric actuators type micro flapping wing aircraft based on soft hinges. The double piezoelectric actuators type micro flapping wing aircraft comprises two bent beam type twin-lamella piezoelectric actuators, two transmission mechanisms in central symmetry distribution, an outer frame surrounding the periphery of the aircraft, and two wing structures containing driven torsion hinges. The bent beam type twin-lamella piezoelectric actuators are bent under the excitation of voltage, the wings are driven to move by the transmission mechanisms, so that a force needed by the motion of the aircraft is generated. By adopting the structure and using the laser micro-cutting technology and soft hinge connection style, the processing and manufacturing of the micro flapping wing aircraft with wingspan of 3 centimeters are achieved. The mechanism is simple and compact in structure; two actuators are respectively used for controlling the two wings so that the aircraft can achieve other motions besides hovering and straight-line flight.

The invention discloses numerical control equipment for plate drilling. The numerical control equipment comprises a worktable and a gantry arranged on the worktable, the lower end of a beam of the gantry is fixedly provided with a hydraulic rod, the lower end of a piston rod of the hydraulic rod is fixedly provided with a drilling machine, the side wall of the drilling machine is fixedly providedwith a protective cover, the inner wall of the upper end of the protective cover is fixedly provided with two dust collecting covers, and the two dust collecting covers are in central symmetry about the drilling machine; the upper end of the worktable is symmetrically and fixedly provided with two L-shaped fixing bases, and a clamping mechanism is arranged at a vertical part of each L-shaped fixing base; the worktable is internally provided with a cavity, a first screw is transversely arranged in the cavity, and one end of the first screw is rotatably connected with the left side wall of the cavity. The numerical control equipment is convenient to operate, the damage to the human body in the drilling process can be avoided, and the plate drilling efficiency is improved.

The present invention relates to a capacitance type micro-acceleration sensor with a symmetrical and straight-girder structure and a manufacturing method thereof. The characteristics reside in that said acceleration sensor consists of a centrosymmetric quality block, an external supporting frame, eight direct elastic girders which are up-down symmetrical for connecting the quality block and the external supporting frame, an upper cover board and a lower cover board. On end of each direct elastic girder is connected to the top or the lateral of the bottom of the quality block that is parallel with the elastic girder, while the other end is connected to inner surface of the external supporting frame vertical to the elastic girder. The capacitance type micro-acceleration sensor with a symmetrical and straight-girder structure can improve the sensitivity at the same time of reducing the transversal effect remarkably. The capacitance type micro-acceleration sensor with a symmetrical and straight-girder structure is made by using the technology of a micro-electronics mechanism system and is a micro-mechanism acceleration sensor with a high performance.

The invention relates to the cutting of rotating surfaces, especially centric symmetric surfaces (1a) of a metal workpiece (1), especially one made of steel or gray cast iron, also when said workpiece is in hardened state, by means of a geometrically determined cutter (2a) or cutters, wherein the axial extension and the material of the surface to be machined are hardly limited or not limited at all and / or the operating time during machining is reduced according to said method and / or the service life of the tool is enhanced and / or the effect of the twist-free condition is achieved, wherein at least one cutter (2a) that is skewed relative to the rotational axis (10) of the workpiece is guided during a feeding motion (3,3′) in a contacting manner on the rotating workpiece and wherein the machining parameters of the rotational axis, especially the forward feed motion in the direction of feeding and the skewed position (x) of the cutter (2a) relative to the longitudinal direction (z), are chosen in such a way that twisting in terms of the degree of twisting (s) and / or the depth of twisting (t), more particularly the depth of twisting, on the surface being machined is minimized, wherein the forward feed motion includes an axial movement.

The invention discloses a metal-oxide gas sensor based on MEMS (Micro-Electro-Mechanic System) and a preparation technology thereof. The gas sensor is characterized by comprising an Si substrate, an insulating layer, two thin-film resistor heating elements, a rectangular micro array, a pair of sensitive electrodes and a metallic oxide three-dimensional multi-level nano-structure produced on the rectangular micro array, wherein partial Si at the lower part of the Si base is removed in an anisotropic manner through wet etching; at the front of the gas sensor, the heating elements and the sensitive electrodes are arranged in a central symmetry and spiral manner, the rectangular micro array is arranged in the center, and the heating elements, the sensitive electrodes and the rectangular micro array are positioned on the same layer; the heating elements can also serve as temperature detecting elements. According to the invention, the nano-structure synthetized by adopting a hydrothermal method can realize the bridge type electrical connection through the mutually crossed dendritic structures, and is finally connected with the sensitive electrodes; the arrangement manner of the rectangular micro array is changed, and nano-materials of different types are replaced, so that the metal-oxide nano gas sensor based on different measuring circuits and sensitive materials of different types can be processed.

The invention discloses a variable-rigidity elastic joint of a cam structure. The variable-rigidity elastic joint is composed of a shell, a shaft and an outer ring. The shaft is arranged at the rotation center of the shell and fixed to the shell. The shell and the outer ring are connected through a rotation pair. A plurality of symmetrical leaf springs are arranged on the outer ring in the radial direction. One end of each leaf spring is fixedly connected with the outer ring, and the other end of each leaf spring penetrates through a spring to be fixedly connected with the shaft. One end of each spring is connected to the shaft, and the other end of each spring is connected to a sliding block. The sliding blocks are arranged in the middles of the leaf springs and connected with the leaf springs in a sliding mode. A cam disk is arranged on the shaft, of a central symmetry structure and connected with the shaft through a rotation pair. A cam roller is arranged at the upper end of each sliding block. Cam transmission is achieved through the cam disk and the cam rollers. The variable-rigidity elastic joint solves the problems that an existing structure is relatively complex and the variable-rigidity characteristic is poor, and the variable-rigidity elastic joint which is simple in structure and allows the rigidity to be regulated in real time in the movement process can be obtained.

The invention relates to a circuit-type fishpond breeding system integrating a circulating water treatment process. The circuit-type fishpond breeding system integrating the circulating water treatment process comprises a fishpond shaped like an annular runway, and sewage treatment systems arranged in an inner ring of the fishpond. Each sewage treatment system comprises a vertical flow type solid-liquid separator (1), wherein a sewage discharging groove (5) perpendicular to the water flow direction is formed in the bottom of the fishpond and communicated with an inlet of the vertical flow type solid-liquid separator (1), an outlet of the vertical flow type solid-liquid separator (1) is communicated with a micro-filtration machine (2), outlet water of the micro-filtration machine (2) adopts a water pump (3) and a water lifting pipe (4) for water lifting and is injected into a biological filter (6), the biological filter (6) is separated from an aeration oxygenation pond (8) through a separation plate and is communicated with the aeration oxygenation pond (8) through a through hole in the lower portion of the separation plate, a water falling pipe (7) is arranged on the lateral wall of the aeration oxygenation pond (8) and communicated with the fishpond, and the water outlet direction at the bottom of the water falling pipe (7) is the same as the water flow direction of the fishpond. The number of the sewage treatment systems is two, and the sewage treatment systems are evenly distributed in the inner ring of the annular fishpond in a central symmetry mode.

The invention discloses a polarization maintaining optical fiber with a small bending radius and a manufacture method of the polarization maintaining optical fiber and relates to the field of optical fiber manufacture. The polarization maintaining optical fiber comprises a silica cladding, a core layer, a second silica cladding ring, a third fluorine-doped silica cladding ring and two stress cat eyes are sequentially arranged in the silica cladding from inside to outside, and the two stress cat eyes are in central symmetry with the core layer. By means of the manufacture method, the bending radius of the manufactured polarization maintaining optical fiber is smaller than 5mm, operating wavelength of the polarization maintaining optical fiber is 1550nm, and supplementary deterioration of the polarization maintaining optical fiber is under 0.4dB / km. According to the polarization maintaining optical fiber, under the condition that the bending radius is small, low-loss information transmission of the polarization maintaining optical fiber is achieved, low supplementary deterioration and good crosstalk characteristics of the polarization maintaining optical fiber are guaranteed, fiber optic sensors with small sizes can be manufactured by means of the polarization maintaining optical fiber, and requirements of users are satisfied.

The invention provides a high-lift-to-drag ratio balance applied to a low-speed wind tunnel. The high-lift-to-drag ratio balance comprises a test model connecting cone, combined force measuring elements, a balance base body, resistance measuring elements, support sheets and a support rod connecting cone, wherein two ends of the balance base body are connected with the model connecting base and the support rod connecting cone through the combined force measuring elements; the balance base body is divided into an upper part and a lower part by an inclined groove which penetrates through the design center of the balance and runs through back and forth; the upper part and the lower part of the balance base body are connected into a whole through front, rear, left and right four groups of support sheets which are symmetrical about the design center of the balance; grooves are formed in the front part and the rear part of the balance base body symmetrically about the design center of the balance; the resistance measuring elements are arranged in the two grooves; and the resistance measuring elements are n-shaped beams (described in the specification); two ends of each n-shaped beam are connected with the balance base body through flexible hinges; and every two adjacent n-shaped beams are arranged anti-symmetrically about a longitudinal symmetric shaft in an up-front and down-back manner. The high-lift-to-drag ratio balance is high in high-lift-to-drag ratio balance, strong in antijamming capability and good in torsion resisting stiffness.

The invention provides a prestressed shear wall and vertical joint combining-connecting structure. The prestressed shear wall and vertical joint combining-connecting structure comprises at least two prestressed shear walls, two pieces of embedded profile steel and one fixing assembly. The embedded profile steel is embedded into the side walls of the prestressed shear walls, and the two pieces of embedded profile steel are arranged between the two prestressed shear walls and are fixed by the fixing assembly. The fixing assembly comprises two clamping plates, multiple hoop bars, multiple bolts and at least four longitudinal bars. The web plates of the two pieces of embedded profile steel are connected through the front clamping plate, the back clamping plate and the bolts. The four longitudinal bars are arranged along the connecting cross sections of the two pieces of embedded profile steel in a central symmetry mode, and the hoop bars are welded on the front clamping plate and the back clamping plate and are in bound connection with the longitudinal bars. The invention further provides a construction method of the prestressed shear wall and vertical joint combining-connecting structure. The prestressed shear wall and vertical joint combining-connecting structure is large in bearing capacity, good in anti-seismic property, superior in integrality, convenient to construct, good in construction quality and good in fireproof performance.

The invention discloses a broadband dual-polarization antenna and a radiating unit thereof. The radiating unit comprises two pairs of symmetrical dipoles with mutually orthogonal polarization, and each pair of symmetrical dipoles comprises a pair of radiation arms and a pair of balens used for being fixed on a metal reflection plate and implementing same side supporting to each radiation arm at the end where the radiation arms are close. Each radiation arm is arranged on a same reference plane, the whole radiating unit and the geometric center of the reference plane are of a symmetrical structure, the reference plane extends towards the bottom directions of the baleens to form a space which is defined as a containing space, each radiation arm is in a shape of closed single line, a main body located on the reference plane exists, the radiation arm is provided with an expanding portion extending to the containing space in a bending mode from the main body of the radiation arm at one end of the radiation arm far away from the corresponding balen. The broadband dual-polarization antenna and the radiating unit lengthen path length of current in the radiation arm by fully using space, thereby being capable of reducing size of the radiation arm based on appointed electrical specifications.

The invention discloses a human lower limb exoskeleton assisting in load bearing. The human lower limb exoskeleton is characterized in that the exoskeleton is of a central symmetry structure; each side is composed of a front branch chain and a rear branch chain; each rear branch chain comprises a backpack module, a rear connection rod and an energy storage module; each energy storage module comprises an energy storage module upper connection shaft, a guide cylinder upper connection rod, a guide cylinder lower connection rod, a guide cylinder upper end cover, a controllable linear damper, a long spring baffle, a long spring, a short spring baffle, a short spring, a short spring guide rod, a short spring check block, an energy storage module lower connection shaft and an energy storage module shaft sleeve; the guide cylinder upper connection rods and the guide cylinder lower connection rods form a prismatic pair through cooperation of the guide cylinder upper end covers and the guide cylinder upper connection rods; the guide cylinder upper end covers are connected with the guide cylinder lower connection rods; the long spring baffles are installed at the tail ends of the guide cylinder upper connection rods; the long springs are installed in the guide cylinder lower connection rods; the upper ends of the short spring guide rods are connected with the short spring baffles, and the short spring check blocks are installed at the lower ends of the short spring guide rods; and the short spring guide rods penetrate the short springs from the centers till the short springs make contact with the short spring baffles so that pre-tightening force can be applied.

This disclosure pertains to the field of small-unmanned aerial vehicles (UAVs). The delta wing vehicle consists of an isosceles triangular shaped lifting body milled from Styrofoam. The longitudinal axis is approximately 65% of the lateral axis. The horizontal wing projections, or tiplets, are attached to the main lifting body at an approximately 10 degree upward angle from horizontal, have a 30 degree sweep back leading edge, and each one comprises 5% of the total wing area. The airfoil is a rhomboid or diamond shape. The chord is swept back at a 45-degree angle from the longitudinal centerline. The airfoil is symmetrical about the longitudinal center. The aircraft is controlled by a set of combined elevator / aileron surfaces (elevons) at the rear as well as a vertical stabilizer / rudder combination. This resulting lightweight UAV can make flat (unbanked) unbanked turns, fly in high winds, and has superior flexibility in payload capability.

The invention discloses a testing device and testing method for simulating the hydraulic fracture characteristic of a concrete bedrock contact surface. The testing device mainly comprises a mold, a steel sheet, pressure measuring guide pipes, a water seal fixture, a water pressure loading system, strain gauges, a clip gauge, a computer and the like. A pair of discs are cut in the mold in a central symmetry mode, can rotate and are used for allowing the steel sheet to be inserted into preformed initial cracks with different thicknesses, widths, roughness and angles; the water seal fixture clamps a test piece in a screwing mode through a screw to seal the water pressure, a high-pressure-resistant water guide pipe is connected with a fixture thread center hole formed in the center of a water seal device through a thread connector, the strain gauges are arranged in the development direction of the cracks, and a coloring agent is added into a water tank connected with the high-pressure-resistant water guide pipe to track the propagation trajectory of the hydraulic fracture cracks. The testing device can be used for studying the hydraulic fracture characteristic of the concrete bedrock contact surface, is simple and convenient to operate and can truly reflect the crack propagation characteristic among contact surfaces of different materials.