236 results about "Cylindrical coordinate system" patented technology

The invention discloses propeller type surface contour error measurement instrument and method. The propeller type surface contour error measurement instrument is characterized in that a gantry structure is adopted, a left upright, a right upright and a top cross beam are arranged on a base, and a revolving spindle is arranged on a cross beam; the lower end of the revolving spindle is horizontally and fixedly connected with a measuring arm; a linear guiderail is arranged on the bottom surface of the measuring arm along the radial direction of the revolving plane of the measuring arm, a working platform capable of doing linear movement along the linear guiderail is arranged on the linear guiderail, and a displacement sensor is arranged on the working platform; and a Y-direction working platform and an X-direction working platform are arranged on the base in an overlapping, and the blade of a detected propeller is arranged in a positioning groove at the top surface of the X-direction working platform. The measuring device and the measuring method are established by adopting a cylindrical coordinate system according to the axial symmetry structure characteristics of the propeller blade. The measuring device and the measuring method are fast in data acquisition, have no objective errors of an operator, and are simple in follow-up error processing and analysis, and can be used for precision measurement on size parameters and geometric error parameters of large revolving parts.

The invention discloses a melt differential three-dimensional printer. The melt differential three-dimensional printer mainly comprises a material melting unit, a micro-droplet jetting unit, a cylindrical-coordinate system molding unit and a rack, wherein a servo motor drives a screw rod to rotate in the material melting unit; a heater, which is fixedly arranged inside a machine cylinder, ensures that granules are entirely plastified through temperature regulation; a molten material is transmitted by the screw rod to the micro-droplet jetting unit; in the micro-droplet jetting unit, the molten material is transmitted into a valve body through a hot runner in a runner plate; a linear servo motor drives a valve needle to do reciprocating motion in the valve body so as to quantitatively and intermittently squeeze the molten material out of a nozzle to form melt micro-droplets; in the cylindrical-coordinate system molding unit, the molten micro-droplets are injected to a bearing table for cooling and deposition molding; the servo motors in the left-right direction and in the vertical direction are respectively engaged with the corresponding screw rod to rotate so as to drive the material melting unit and the micro-droplet jetting unit to move along the left-right direction and the vertical direction; a circumference servo motor drives the bearing table with a worm gear to rotate through a worm rod so as to realize three-dimensional movement under a cylindrical-coordinate system.

The invention provides a multiple projector rotating screen based 3D display system, including: one rotating screen, driven by motor; an image processing device, decomposes the 3D physical model in the cylindrical coordinate system in a series of multiple angular 2D images and sent to the data processing unit of all projectors; at least two projectors arranged around the rotating screen, synchronously project a 2D image with the corresponding angle on one of the rotating screen, thereby restructured the 3D image similar with that of actual objects. The invention may improve the updating rate, resolution and gray step-scale, based on the current available technical level of software and hardware, the lower cost, high display effect of 3D display device may be manufactured.

The invention provides a real three-dimensional display method based on the fact that a three-dimensional image of a rotational screen of a multi-projector is touchable. The method comprises the following steps that: firstly, three-dimensional space of the three-dimensional image displayed is described by utilization of a circular cylindrical coordinate, and a series of section images in different angles along the diameter direction are analyzed; secondly, a plurality of projectors which are arranged along the circumference and rotated along with a screen project in turn, and the section images are projected to the screen to form a stereo image; thirdly, the stereo image is secondarily imaged on a given position of the space through reflectors which are arranged on the circumference of the screen so as to realize the touchable function. By utilization of the method, the stereo image can be directly touched by hands and simultaneously the contrast of the stereo image is effectively improved. The invention also provides a diametrical alternate illumination optical system of the projector used in the method, and diametrical alternate illumination can be realized by utilization of a light source.

Rotational hardstop assemblies that provide greater than 360 degrees of non-continuous rotation for rotating mechanisms are provided. In certain embodiments, an assembly is used to provide 630 or more degrees of rotation for the shoulder axis of a robot, such as a wafer transfer robot. The rotational hardstop assemblies include opposing magnets as springs. According to various embodiments, the opposing magnets provide non-contact engagement and produce no contact noise nor have any wear over time. The rotational hardstop assemblies provide the ability to location from either direction of rotation of a robot cylindrical coordinate system.

The inventive method consists in: modeling for thermal analysis of heating and temperature rise of the main shaft, using a cylindrical-coordinate system for the temperature distribution of the axially symmetric structure and determining the boundary condition; calculating friction heat and power loss of front and back bearings of main shaft in a state of different speeds and different pretightening forces; determining the relation of axial shifting of the bearing with the pretightening forces; according to the above calculated data, choosing material for making double-layer bushing and making length different double-layer bushing size of the sleeve because the extension volume of the bushing heat expansion depends on the length of the sleeve.

The invention relates to a double-arm transmission robot applied to a clean environment, which is used for the transmission and high-precision positioning placement of a large-diameter semiconductor silicon wafer in a high-cleanliness environment. The double-arm transmission robot is in the structural form of R-theta type and has the working principle of a space structure based on a cylindrical coordinate system and the characteristic of independent control of all motion shafts. The double-arm transmission robot mainly comprises an R-axis left arm mechanism, an R-axis right arm mechanism, a T-axis rotating mechanism, a Z-axis lifting mechanism, and the like and seals the pollution of a drive mechanism on an external environment by adopting a special seal device so as to be suitable for the high-cleanliness production environment requirement.

In the present invention, products of sliding rail, linear displacement transducer, angular displacement transducer, transmission screw and motor on the market are used to assemble a three coordinate measuring instrument with cylindrical coordinate system. The instrument has three parts of cross arm, vertical arm and base for realizing movement of three-dimensional direction to achieve purpose of measuring workpieces in various outlines.

The invention relates to a visual detection device used for a fine long cavity body, belonging to the visual detection device. The problem that an end photographing system can not precisely position is solved and simultaneously the cost is lowered. The detection device comprises a base, a lifting mechanism, a motion mechanism and a photographing system. The vertically directional displacement of the motion mechanism is adjusted by the lifting mechanism to lead to the coaxial type of a probing rod and the cavity body to be detected. The motion mechanism comprises the probing rod, a probing rod hollow sleeve, a central gear, a probing rod supporting base, a translational motor cabinet, a rack, a translational motor gear, a motion supporting station, a rotary motor gear, a rotary motor and a translational motor. The photographing system is arranged on the probing bar end of the motion mechanism and comprises a supporting board, a photographer, a prism and a light source. Based on the design of a cylindrical coordinates, the device has the advantages of circumferential rotation, axis translation, radial fine adjustment, small gyration radius, long axial stroke, good rigidity and convenient processing and manufacturing. The visual detection device is applied to the assembling, the painting or the welding quality detection of fine long cylindrical cavity body which is not sealed or is provided with one sealed end and can not be reached by human.

The invention provides a three-dimension mesh model copyright verification method, which comprises the following steps that S1, light holographical encryption copyright watermark information is generated; S2, a three-dimension mesh model is preprocessed; S3, a model geometrical characteristic matrix is built in a cylindrical coordinate system; S4, the geometrical characteristic matrix is subjected to QR decomposition to embed copyright watermark information; S5, the three-dimension mesh model embedded with the copyright watermark information is issued on public information platforms such as Internet; S6, the obtained three-dimension mesh model to be detected is subjected to pre-processing for carrying out QR decomposition on the geometrical characteristic matrix to extract a copyright encryption information grey-scale map, a copyright two-value watermark image is obtained through Fourier inversion and filtering by a two-order Butterworth high pass filter, and the copyright ownership of the three-dimension mesh model can be judged through human eye identification. The method belongs to an air space blind watermark algorithm, higher robustness is realized, and the obvious problems that the existing three-dimension mesh model copyright verification method can be easily cracked and copied, and the copyright anti-fake certification cannot be conveniently or effectively carried out are solved.

Conversion of color data values from a rectangular coordinate system such as CIELab to a cylindrical coordinate system such as CIELCh using two one-dimensional look-up tables, one each for the C value and the h value. The one-dimensional look-up tables are accessed by defining a new variable γ as the absolute value of the ratio of b and a.

The invention discloses a method for converting three-dimensional point cloud into two-dimensional image, which comprises the following steps: acquiring three-dimensional point cloud information of anobject to be measured by a three-dimensional laser scanning device, taking the three-dimensional scanning device as a coordinate center, establishing a three-dimensional Cartesian coordinate system,and calibrating the Cartesian coordinates of each point in the three-dimensional point cloud; Taking three-dimensional scanning equipment as coordinate center, establishing the three-dimensional cylindrical coordinate system, and establishing the transformation relationship between Cartesian coordinates and cylindrical coordinates of each point in three-dimensional point cloud, and correpsoondingthe three-dimensional point cloud in Cartesian space coordinate system to the cylindrical coordinate system. Expanding The cylindrical coordinates of the three-dimensional cylindrical coordinate system to construct a two-dimensional cylindrical coordinate system, and the conversion relationship between the cylindrical coordinates of each point in the three-dimensional point cloud and establishingthe cylindrical coordinates of the two-dimensional cylindrical coordinate system , and enabling the three-dimensional point cloud in the cylindrical coordinate system to corresponded to the two-dimensional cylindrical coordinate system to generate the two-dimensional pixel coordinates of the object to be measured. The invention can convert the scanned three-dimensional point cloud into two-dimensional image for research, and simplifies the calculation process.

The invention discloses a jib crane hoisting operation anti-collision method and a system. According to the system, an obstacle classification model is established, and the appearance and position information of obstacles in an operation area is accurately acquired by adopting a crane jib head autonomous detection and study method. A cylindrical coordinate system of a crane is established, the operation area is divided into different sectors according to slewing angles, the sectors are divided into different fan-shaped grids according to the distance from a slewing center, environmental data of the operation area are precisely stored based on the fan-shaped grids, and a hoisting safe operation three-dimensional boundary wall is generated by utilizing the data of the fan-shaped grids. Motion and position parameters of a crane jib at the next moment are predicted by using a weighted linear regression model based on the position information of the crane jib at the most recent 20 moments. Aiming at the predicted motion and different distances from the boundary wall of the crane jib, crane jib control strategies such as no intervention, speed limiting, micro-motion and prohibition are adopted. Functional tests in an actual operation environment show that the system can effectively prevent the collision between the crane jib and the obstacles in the operation area.

A superconducting current lead includes a cylindrical support member 3, and superconducting wire material units 1 each of which is fixed onto the support member and each of which is composed of a single tape-like oxide superconducting wire material or a laminated tape-like oxide superconducting wire material, wherein tape surf aces of the superconducting wire material units are disposed in parallel with a circumferential direction in a cylindrical coordinate system, and the cylindrical support member is formed from a low thermal conductivity material.

The invention provides a reaction position positioning method and apparatus. The method includes receiving the energy information of the visible photon coupled to a scintillation crystal, detected by at least one photoelectric sensor array, and generated by the reaction of the gamma photon with the scintillation crystal, wherein the scintillation crystal is an integrated scintillation crystal and has a through hole for receiving an object to be imaged, and the gamma photon is generated by the positron annihilation effect in the object to be imaged; and determining the reaction position of the gamma photon in the scintillation crystal according to the received energy information, wherein the reaction position is represented by a cylindrical coordinate system. According to the invention, by providing a way for positioning the reaction position of the gamma photon for a positron emission imaging apparatus with the integrated scintillation crystal, the problem that a conventional position calculation method is not suitable for the improved positron emission imaging apparatus can be solved.

Motion compensation for coherent combination of pulses facilitates a SAR image of a scene on earth's surface. A great circle (406) is centered with respect to the earth's center, The great circle (406) has an axis (412) perpendicular to a first plane. Axis (412) passes through the earth's center. The first plane contains great circle (406) and includes the earth's center. Great circle (406) has a first center defined by an intersection of the first plane and axis (412). The scene has one or more radar scatterers and is located on a surface (402). The radar system is mounted on a moving platform (400) moving with a component of motion in a direction along great circle (406). The radar comprises a radar receiver for digitizing the radar returns having a phase from scatterers on surface (402), and a computer for focusing the phase of said radar returns from the scatterers on surface (402). The surface (402) is located on a local scene centerline circle (408), the local scene centerline circle (408) defining a second plane. This second plane is parallel to the first plane. The local scene centerline circle (408) is centered on the axis at a second center, where the second center is displaced with respect to the first center along the axis by a distance (414). The phase of the radar returns received from the scene is compensated for the motion of the moving platform (400) using a cylindrical coordinate system referenced with respect to the second center to yield a SAR image.

The invention relates to a method for generating a free-form surface turning tool path through a control point drive projection. The method comprises the steps that a plane perpendicular to the Z axisof a workpiece coordinate system is built at the position zd away from the top of the to-be-processed free-form surface in the workpiece coordinate system, an equidistant spiral line is generated inthe plane and discretized, discretized points are converted into a cylindrical coordinate system (rho, theta, zd), the to-be-processed free-form surface is rotated by the angle theta around the Z axis, the smallest distance delta between each point of the tool edge curve on the equidistant spiral line and the rotated to-be-processed free-form surface is calculated, and therefore the coordinate (rho, 0, zd-delta) of the tool control point is obtained, wherein a tool is a cylindrical turning tool. The projection driving track of the tool control point is preferentially generated, and stability of feeding movement of the tool in the X direction is ensured. By means of the method, a universal model of cylindrical diamond turning tools rather than only zero degree front angle tools is built, and the defects of traditional tool path design methods are overcome.

The invention discloses a three-dimensional focal imaging method of a look-down array antenna synthetic aperture radar, which relates to radar technology. The method comprises: A) performing slant-range compression of collected original echo data of the look-down array antenna synthetic aperture radar; B) performing azimuth range migration correction of a signal obtained by the step A); C) performing the azimuth compression of a signal obtained by the step B); E) performing the ground-range range migration correction of the signal which is subjected to slant-range compression and azimuth compression; and F) performing the ground-range slant removal and ground-range Fourier transform of the signal obtained by the step E), and reestablishing the three-dimensional radar image of an imaged area in a cylindrical coordinate system. In the method of the invention, fewer antenna array elements are used for reestablishing the three-dimensional radar image of the imaged area, the range migration correction problem, which is not solved in the conventional three-dimensional imaging method, is solved, the ground-range wave beam forming calculation performed in the conventional three-dimension imaging method is converted into one time of complex multiplication and the Fourier transform, and a three-dimensional resolution image is thus acquired, and the required imaging time is reduced.

The invention discloses a transient electromagnetic forward modeling method applicable to an irregular transmitting loop. The method comprises the steps of using a ground point corresponding to the center of a receiving coil as an original point, building a cylindrical-coordinate system, and building a frequency domain expression of the vortex electric field component at a receiving point; presenting the frequency domain expression of the vortex electric field component as a Hankel integral form, and working out the response magnitude of the frequency domain of the vortex electric field component; working out the response magnitude of the time domain of the vortex electric field component; recording coordinates of inflection points of the irregular transmitting loop, and obtaining a function expression of a segmented loop between every two adjacent inflection points; conducting integration on the segmented loops by using time domain response of the vortex electric field component so as to obtain the voltage value of each segmented loop, and calculating the sum of the voltage values of all the segmented loops so as to obtain transient response of the irregular transmitting loop. The method is applicable to a ground, ocean and aviation transient electromagnetic method one-dimensional forward modeling algorithm of the irregular transmitting loop.

There is provided a gear pair evaluation apparatus capable of performing accurate tooth surface analysis based on actual tooth surface measurement information without using information about a reference tooth surface. A processing unit 6 associates three-dimensional coordinate data on a gear tooth surface 102G and three-dimensional coordinate data on a pinion tooth surface 102P with each other at a predetermined meshing rotational position and converts the three-dimensional coordinate data into three-dimensional coordinate data on a cylindrical coordinate system based on the gear 101G. The processing unit 6 generates functions representing points on the pinion tooth surface 102P on the basis of the three-dimensional coordinate data on the pinion tooth surface 102P and calculates the coordinates of points on the pinion tooth surface 102P that correspond to points (grid points) on the gear tooth surface 102G by using the functions.

The invention provides a blood vessel image processing apparatus, blood vessel image processing program, and blood vessel image processing method. [Problem] To delete an abnormal protrusion region from a three-dimensional image of a blood vessel. On the basis of three-dimensional blood vessel data representing the three-dimensional shape of the blood vessel, this control apparatus 102 identifies center lines of the blood vessel, identifies a center line of a protruding portion of the blood vessel from among the center lines, and identifies a center line that branches off from the center line of the protruding portion. Then, for three-dimensional blood vessel data of the blood vessel corresponding to the branching center line, the control apparatus 102 defines a cylindrical coordinate system with the circumferential direction of the blood vessel from the center line, the radial direction of the blood vessel from the center line, and the direction of the center line as coordinate axes, and converts blood vessel data expressed in the cylindrical coordinate system into blood vessel data in an orthogonal coordinate system. In the blood vessel data in the orthogonal coordinate system, the control apparatus 102 uses a coordinate value along the radial-direction coordinate axis for a first coordinate value along the center-line-direction coordinate axis and a coordinate value along theradial-direction coordinate axis for a second coordinate value along the center-line-direction coordinate axis to interpolate coordinate values along the radial-direction coordinate axis from the first coordinate value to the second coordinate value, and converts the resulting blood vessel data in the orthogonal coordinate system into blood vessel data in the cylindrical coordinate system.

A spacecraft autonomous fly-around intersection control system verification device and a spacecraft autonomous fly-around intersection control method belong to the field of aerospace control ground simulation. The spacecraft autonomous fly-around intersection control system verification device comprises a central fixed platform, a three-axle turntable target gesture simulator, a three-axis turntable tracked gesture simulator, a circumferential movement module, a radial movement module, a vertical movement module, a nine-freedom motion measurement and control system, a simulator dynamic calculating system and a spacecraft autonomous fly-around intersection control system. A verification process is characterized in that a simulator dynamic model is established based on a method that length of a similar theory zooms similarly with time dimension; an anticipated motion track of the simulator is obtained through calculation; and a simulator is made to track the anticipated track for realizing spacecraft autonomous fly-around intersection motion ground simulation. The verification device simulates and tracks three-axis position change of the simulator in a cylindrical coordinate system. The verification device can verify ll-direction autonomous intersection control tasks and particularly comprises a spacecraft autonomous fly-around intersection control task. Compared with existing similar devices, the spacecraft autonomous fly-around intersection control system verification device has advantages of expanding ground verification capability and realizing simple and applicable structure.

The invention belongs to the technical field of intelligent manufacturing equipment, and relates to a rectangular tube or circular tube intelligent centering, clamping and rotating device. According to the device, pressure hydraulic oil is ingeniously is introduced into a rotary system through a sealed oil passing groove formed between two mutually rotary parts, and a hydraulic hose is prevented from being twisted so that a rotary part can continuously rotate without limitation, and the use is very convenient. A cog gear is ingeniously used for driving two racks to synchronously and horizontally move in opposite directions so that the center line of a rectangular tube can well coincide with the center line of a circular ring turntable, the device is very beneficial to demonstration or programming of intelligent cutting equipment, a cylindrical coordinate system is conveniently built, coordinate conversion is not needed, and the device is more convenient to use compared with an eccentric clamping mode. The device is matched with the intelligent work equipment so that intersection lines such as round holes and elliptical holes can be cut out and complex hollowed-out patterns or characters can also be cut out. The device achieves automatic clamping, turning and position changing, manual work is not needed, and manpower is saved.

The invention provides a three-dimensional imaging method based on multi-perspective imaging. The method includes the steps of firstly, generating N three-dimensional images of different angle ranges under the same Cartesian coordinate system; secondly, generating N window functions corresponding to the N three-dimensional images, and converting the N window functions from a cylindrical coordinate system into the Cartesian coordinate system; thirdly, respectively correspondingly multiplying the N three-dimensional images and the N window functions, and performing summation to obtain human body three-dimensional imaging data. The three-dimensional imaging method has the advantages that the 360-degree full-resolution three-dimensional imaging method is provided, a three-dimensional image contains 360-degree target information, the problem of resolution lowering of edge images is solved effectively, and rich, accurate and comprehensive information is provided for subsequent image processing.

A method of simulating a borehole acoustic response in an anisotropic formation of the crust of the earth, the method comprising: formulating a geometric model of the formation, the geometric model comprising a plurality of layers definable in a cylindrical coordinate system defined by an axial direction normal to each of the layers, a radial direction relative to the axial direction, and a circumferential direction relative to the axial direction; formulating a computational model of wave propagation in the formation, the computational model comprising one or more field variables and a wave equation describing a behaviour of the one or more field variables, wherein the one or more field variables are represented as respective Fourier series expansions of π-periodic harmonics in the circumferential direction, and numerically solving the computational model.

The invention discloses an underwater sound field numerical simulation method and system based on a Chebyshev polynomial spectrum and a medium. The method comprises the following steps: establishing asimplified control equation of an acoustic propagation Helmholtz equation under a cylindrical coordinate system; completing independent variable transformation from a z coordinate to an x coordinateby using the simplified control equation; implementing Chebyshev forward transformation on the simplified control equation, and mapping a physical space to a spectral space to form a discretized linear equation set in the spectral space; solving the discretized linear equation set in the spectral space to obtain a solution in the spectral space; implementing Chebyshev inverse transformation on thesolution in the spectral space, and mapping the solution in the spectral space back to the physical space; completing independent variable inverse transformation from an x coordinate to a z coordinate to obtain u (r, z), and solving a sound pressure field p; calculating propagation losses. The method is suitable for obtaining higher calculation precision under the condition that few discrete gridpoints are used, the calculation performance of a hardware platform can be brought into full play, and the speed of numerical simulation is remarkably increased.

The invention relates to a method for image registration, in particular to a space registering method based on a panoramic all-in-one speed dome camera. The technical problem that an existing panoramic all-in-one speed dome camera can not be accurately located is solved. The space registering method based on the panoramic all-in-one speed dome camera comprises the following steps that step one, a panoramic cylindrical coordinate system, a speed dome camera coordinate system and a spherical surface coordinate system are established; step two, change from the panoramic cylindrical coordinate system to the spherical surface coordinate system is conducted and change from the speed dome camera coordinate system to the spherical surface coordinate system is conducted; step three, characteristic points of a whole-screen image and characteristic points of a speed dome camera image are matched; step four, according to the matched characteristic points, a changing matrix is solved; step five, a point or a zone needing to be observed is selected from the panoramic image, and the rotating angle of a speed dome camera is calculated. The rotating angle of the speed dome camera can be rapidly and accurately calculated, the local scene is shot, and the space registering method based on the panoramic speed dome camera all-in-one machine has the advantages of improving the performance of a monitoring device and satisfying the requirements of a user.

The invention discloses a portable 3D printer, and belongs to the field of 3D printers. On the basis of a feeding device and a control system in the prior art, remaining portions are creatively designed. The printer comprises a stand column fixed with a box body during work and a printing platform driven by a third motor to linearly move in the length direction of the stand column; during folding, the printing platform can rotate around the axis perpendicular to the length direction of the stand column, the top of the stand column is rotatably connected with a rotating arm, a first motor drives the rotating arm to rotate around the axis parallel to the length direction of the stand column, a nozzle is in sliding connection with the rotating arm, and a second motor drives the nozzle to do linear motion in the length direction of the rotating arm, and a box body containing the 3D printer in the folding state is further included; according to the 3D printer, the nozzle moves in the space in a cylindrical coordinate system manner, the compact structural design is achieved, the manufacturing cost is reduced, and after folding, the printer can be arranged in the box body to be carried.

The invention discloses a synchronous telescopic adaptive multi-point support fixture for the processing of annular thin-wall workpieces, and belongs to the technical field of machining. The synchronous telescopic adaptive multi-point support fixture comprises a base, lower pressing plate assemblies, a lower bearing fixing assembly, upright columns, a height regulating plate, connecting rod and sliding block mechanisms, a lead screw nut mechanism, floating auxiliary supporting assemblies, an upper bearing fixing assembly and an upper press cover, wherein a single degree of freedom height regulating structure is formed by the upright columns and the height regulating plate, and in combination with the lead screw nut mechanism and the connecting rod and sliding block mechanisms, the synchronous telescopic adaptive multi-point support fixture forms a cylindrical coordinate type supporting system taking radial positions and axial positions as control variables in terms of spatial orientation and motion mode. The synchronous telescopic adaptive multi-point support fixture has the advantages that synchronous telescoping with multi-point radial support can be realized, and uniform supportcan be provided for the workpieces; the support regulating range is large, so that supporting demands of the workpieces with different diameters and heights can be met.