75results about How to "Guaranteed geometric accuracy" patented technology

The invention provides a three-dimensional building fine geometric reconstruction method integrating airborne and vehicle-mounted three-dimensional laser point clouds and streetscape images. The method comprises the following steps: (1) a quick modeling method based on airborne laser data; (2) combining the semantic segmentation framework of the vehicle-mounted point cloud and the image; and (3) amodel automatic enhancement algorithm fusing multi-source data. According to the method, airborne laser point cloud, vehicle-mounted laser point cloud and streetscape images are taken as research objects, model reconstruction, model enhancement and updating are taken as targets, joint processing of point cloud and image data of different platforms is realized, and the fusion potential of variousdata is fully mined. The final research result will perfect the fusion and fine modeling framework of vehicle-mounted-airborne data, promote the development of the point cloud data semantic segmentation technology, and serve the emerging application fields of unmanned driving and the like.

Provided is a large-area complex-terrain-region unmanned plane sequence image rapid seamless splicing method which comprises the following steps: to begin with, with air strip arrangement features of unmanned plane image sequence being prior knowledge, carrying out inter-image multiple-overlap SIFT feature point extraction and matching; then, carrying out matching point gross error removing and purifying based on random sample consensus algorithm, and solving transformation parameters of each image in spliced regions in an adjustment manner through an Levenberg-Marquardt algorithm; next, carrying out overlapped region image optimized selection according to the relative position relationship between central projection image point displacement rules and the images, and determining splicing lines; and finally, carrying out image uniform-coloring and fusion at the edge-connection places, and outputting spliced images, thereby realizing mass unmanned plane image seamless splicing. The seamless splicing method helps to improve the extraction efficiency of the SIFT feature points, guarantee the geometric accuracy of the spliced images, and eliminate the tiny color difference at the two sides of the image splicing line, and thus the spliced images with natural color transition and good natural object and landform continuity are obtained.

The invention discloses a limited bracket construction method of a large-span S-shaped steel box girder. The steel box girder comprises 14 small sections of prefabricated steel box girders; and the 14small sections of prefabricated steel box girders are assembled into seven large sections at a construction site, and then the seven large sections are hoisted and fixed. The construction method comprises the following specific steps of: prefabricating and assembling the steel box girders, constructing temporary brackets in water, hoisting and positioning steel box girder section blocks, connecting steel box girder interfaces, constructing closure sections and welding the collar extension of the steel box girders. According to the limited bracket construction method, a prefabricated assemblymode is used during construction; a floating crane is used for assembly, so that the occupation and pollution of a water area under a bridge are reduced; the parallel operation of multiple processes speeds up the construction progress and shortens the construction period; the temporary brackets are arranged only at circular seams of large-section girder joints; and the brackets occupy small space,thereby facilitating the navigation under the bridge in the construction state and reducing the influence on the navigation under the lake-across construction bridge and surrounding social environments.

The invention discloses a decarburization cleaner. Perchloroethylene and methylen chloride or dichloropropane without flammable risk are used as decarburization solvents of the invention; on the basis of the permeability and dissolution of the solvents, the surfactant sodium alkyl sulfonate is compounded, thus promoting and improving the dirt-removing power, and trolamine is taken as antirusting agent without affecting the activity of the surfactant. The invention also discloses a formula and a preparation method of the decarburization cleaner. No heating or stirring is needed in using the invention, excellent using effect can be achieved by soaking at room temperature, energy consumption can be reduced remarkably. The pH value is neutral, thus having no corrosion on the surface of the material. The product has the characteristics of low toxicity, non-combustion and the like, thus the safety is improved greatly. The invention can be recycled only by simple filtering, thus saving using cost.

The invention discloses a numerical control processing method and device for a complex molded surface of a rotor blade of an air compressor. The processing method comprises the steps of clamping the blade, selecting a milling cutter, and determining the milling mode of the blade and the milling sequence of the blade, wherein the back end of the blade is clamped through tightening; the milling cutter adopts a cylindrical cutter; the milling mode of the blade is spiral surrounding milling; and the milling sequence of the blade is that firstly, the edge is cut, then, a blade body is milled, then, a margin plate is milled, and finally, a root is milled. According to the processing method, the deformation in processing is reduced, the geometric accuracy and positional accuracy of the blade are guaranteed, the service life of the cutter is prolonged, the integrity of the blade surface is improved, the processing efficiency is improved, and the problems of overcutting and disorder of a cutter path are solved.

The invention belongs to the field of a numerical control precise measuring device, and relates to a middle driving type dense bead shaft system mechanism. The middle driving type dense bead shaft system mechanism comprises four axial thrust dense bead shaft systems and two radial dense bead shaft systems, a transmission shaft and a locking member. The four axial thrust dense bead shaft systems are arranged on both sides of a middle step shaft. The radial dense bead shaft systems are respectively arranged between the two axial thrust dense bead shaft systems. The end faces of the bearing retainer rings of the axial thrust dense bead shaft systems close to the radial dense bead shaft systems and the end faces of the radial dense bead shaft systems and a retaining frame which are coplanar are coplanar. The transmission shaft is in threaded connection with a revolving member through a screw and maintains a relatively unchanged position relation with the revolving member through a cylindrical pin. The shaft sleeve is in threaded connection to a fixed piece through a screw. The maximum rigidity/inertia ratio is guaranteed, the resistance to overturn is strong, the revolving precision is high, the stress is uniform, and the positioning precision can reach 1'. The processing difficulty is reduced, and the size and geometric accuracy of a ball working rollaway nest are easy to guarantee.

The invention provides a trough type solar heat collector bracket and a mounting method thereof. The trough type solar heat collector bracket comprises a torque frame body, a transmission shaft, a connecting end plate (2), a first reflector support arm (3), a second reflector support arm (4) and a heat collecting pipe bracket (5). The trough type solar heat collector bracket has the advantages that a complicated clamping rack does not need to be built, so that site assembly difficulty and transporting cost are reduced; and at the same time, the geometric precision of a heat collector is ensured, and the purposes of reducing the structural weight of the heat collector and facilitating maintenance are also achieved. A feasible scheme is provided for the design optimization of the trough type heat collector, and the reduction of the whole building cost of a solar power plant is also facilitated.

The invention discloses a close shot large span digital photogrammetry system and method. The system comprises a rectangular collecting platform, guide rails, cameras, a three-dimensional calibrating board and a two-dimensional control filed. The three-dimensional calibrating board comprises a plurality of calibrating marks distributed evenly, each calibrating mark comprises a cylindrical type wooden stick and a round wooden board on the top surface of each cylindrical type wooden stick, the cylindrical type wooden sticks of all the calibrating marks are different in height, and the cylindrical type wooden sticks of the calibrating marks located in the middle of the three-dimensional board are higher than those located on the peripheral of the calibrating marks. The two-dimensional control field comprises a plurality of control point marks distributed on the end face of the edge of the rectangular collecting platform, the control point marks form the control points of the two-dimensional control field, and each control point mark comprises a round wooden board. The close shot large span digital photogrammetry system and method can enable images to achieve the fidelity of high-precision geometrical information.

The invention provides a modularization type material addition and reduction composite repairing method for a defective region of a component surface and relates to the technical field of machining. The main process of the method comprises the following steps of: implementing three-dimensional scanning on the defective region of the component surface and acquiring point cloud data of a to-be-repaired region; calculating the characteristic parameters of the defective region according to the point cloud data; selecting a corresponding geometric module according to the characteristic parameters;implementing modular milling and removal on the defective region to obtain a regular to-be-repaired region; implementing modular laser melt-coating repairing on the to-be-repaired region; and precisely milling the laser-repaired surface to end the repairing. By adopting a material addition and reduction composite way, the method provided by the invention repairs a complicated irregular defective appearance into a regular geometry; on the basis, the modular to-be-repaired geometry is subjected to laser melt-coating repairing; and the operation route is conveniently and quickly planned, so the overall repairing efficiency is improved. Beside, the precise milling for the laser melt-coating region can maintain the repairing precision of the contour of the repaired surface, and the use performance of the repaired surface is also improved.

The invention provides a cutter shaft optimization method for curved surface numerical control machining ball-end milling cutter abrasion control. The method comprises the following steps: firstly, constructing a cutter-workpiece meshing area at each cutter location point according to an input cutter path and geometrical information, and calculating an interference-free cutter shaft space at eachcutter location point; dividing the cutting edge of the cutter into a plurality of cutting intervals along the axial direction of the cutter; calculating the cutting length of each cutting interval ofthe cutter at each cutter location point under an initial cutter shaft according to the obtained cutter-workpiece meshing area to obtain the cutting length of the whole part machined by each cuttinginterval of the cutter edge, and calculating cutter abrasion loss of each cutting interval according to the abrasion rate; and finally, by adopting a fixed cutter shaft strategy, calculating cutter shaft direction in which the cutter abrasion is uniformly distributed in each cutting interval of the cutting edge from the non-interference cutter shaft space of each cutter location point. The methodis high in practicability and operability; and cutter abrasion is evenly distributed by adjusting the cutter shaft, and the problem that the cutter loses efficacy too fast due to the fact that the cutter abrasion is concentrated in a local area can be effectively solved.

A measuring machine having a base (10), a touch signal probe (P), a moving mechanism (20) for retaining the touch signal probe (P) movably in three-dimensional directions, and a controller (60) for controlling a movement of the moving mechanism (20) and for acquiring coordinates value of respective axes based on a contact signal from the touch signal probe (P) to measure a dimension etc. of a workpiece based on the coordinates value is provided. Main structural members structuring the moving mechanism (20), more specifically, a column (21), a supporter (22), a X-beam (23), a Z-axis structure (25) and a Z-axis spindle (26) are made of aluminum or aluminum alloy including aluminum as main component, which has large thermal conductivity, thereby making temperature distribution uniform to improve geometrical accuracy.

A wax material used for electroforming is prepared from Sichuan wax, earth wax, rosin, beeswax and titanium white powder.

An x-ray recording system is for differential phase contrast imaging of an examination object (6) via phase stepping. In an embodiment, the x-ray recording system includes at least one x-ray emitter (3) for generating quasi coherent x-ray radiation; an x-ray image detector (4) with pixels arranged in a matrix; a defraction or phase grating (17) arranged between the examination object (6) and the x-ray image detector (4); and an analyzer grating (18) assigned to the phase grating (17), wherein the x-ray emitter (3) the x-ray image detector (4), the phase grating (17) and the analyzer grating (18) for the phase contrast imaging form components (32, K1 to Kn) in an arrangement. According to an embodiment, at least one measuring apparatus (34) for determining deviations in the geometric ratios of the components relative to one another from the geometry target, an analysis unit (35, 40) for evaluating the measured deviations, a computing unit (36, 41) for determining correction values and at least one correction device (37, 37, 42, 46) for setting the geometric ratios of the components (32, K1 to Kn) are included.

The invention belongs to the technical field of steel structural components, and in particular, discloses a double-curve bent component machining process. The double-curve bent component machining process comprises the following steps: (1) bent part blanking: steel plates and profiles are manufactured as single part plates for manufacturing double-curve bent components; (2) grooves are machined; (3) no-mold formation: wing webs are warped before box assembly through the following steps: (A) the part plates are bent by adopting a three-center circle bending machine according to drawing requirements; (B) the qualified bent part plates are warped by using a hydropress according to drawing warping requirements; and (C) self-inspection is performed on machined parts; and the inspection mode isto use foetal membranes or sample plates for warping amplitude detection; (4) sample mold frames of components are warped; and the mold frames are manufactured; (5) assembly of warped components: webs, baseplates and side plates are assembled by using the mold frames; and (6) the warped components are welded. The process can effectively solve the problems of high machining difficulty and low machining size precision of the double-curve bent components.