Patent TW-200912248-A (TW)
Title: Portable automatic calibrator for precise measurement of spatial coordinate
Inventor: LIN CHEN-WANG
IPC: G01B5/008
Filed: 2007-09-04
Abstract: This invention relates to a portable automatic calibrator for precise measurement of spatial coordinate, comprising a supporting base, a ball array board, and an automatic driving device; by using a pair of randomly chosen ball center distance deviations from an accurately known ball array, each ball center distance deviation of the entire ball array is obtained with the application of symmetrically associated combination calibration method of one dimensional space ball array in conjunction with electrical control; furthermore, a symmetrical combination comparison measurement is performed between the standard point array formed by each ball center of the ball array and the point array of the space of the measurement machine with the application of the least square theory to process the measured value so as to obtain the spatial point errors of the measurement machine in the spatial coordinate being tested; by utilizing common data decomposition method, 21 error items of the geometric structure of the device being tested can be obtained. With the use of the entire symmetrically associated combination, the calibration accuracy of one dimensional ball array can be provided with a high precision standard; in addition, because the ball array is movable on the slide rail of the calibration device, the range of calibration can be expanded several times greater than the standard length of the ball array; prior to the calibration, the system needs only to define one of the ball center distance on the ball board as the standard measurement scale in order to simultaneously affirm the precision of a previously unknown one dimensional ball array and the precision of a device being tested after a single measurement step, allowing a calibration process to be performed easily. In addition, this calibration device does not need periodic calibration according to the stringent national standards for volume and value; instead, immediate examination demarcation prior to use performed by each department with its own measurement standard and simple devices will suffice; therefore, long term stability of the calibration device is not required, the manufacture and design standards of the calibration device can be lower. This invention not only can be used to calibrate and measure the precision of a three-dimensional coordinate measurement machine, but also can be used in one-, two- or three- dimensional linear motion device having a spatial probe; in addition, it is applicable to the detection and calibration of other devices and precision machinery. With this invention, the automatic calibration device offers advantages of high precision, wide calibration range, utility, real-time, and low production cost, and has a very high applicable value to domestic and oversea industries.This invention relates to a portable automatic calibrator for precise measurement and calibration of spatial coordinate, comprising a supporting base, a ball array board, and an automatic driving device; by using a pair of randomly chosen ball center distance deviations from an accurately known ball array, each ball center distance deviation of the entire ball array is obtained with the application of symmetrically associated combination calibration method of one dimensional space ball array in conjunction with electrical control; furthermore, a symmetrical combination comparison measurement is performed between the standard point array formed by each ball center of the ball array and the point array of the space of the measurement machine with the application of the least square theory to process the measured value so as to obtain the spatial point errors of the measurement machine in the spatial coordinate being tested; by utilizing common data decomposition method, 21 error items of the geometric structure of the device being tested can be obtained. With the use of the entire symmetrically associated combination, the calibration accuracy of one dimensional ball array can be provided with a high precision standard; in addition, because the ball array is movable on the slide rail of the calibration device, the range of calibration can be expanded several times greater than the standard length of the ball array; prior to the calibration, the system needs only to define one of the ball center distance on the ball board as the standard measurement scale in order to simultaneously affirm the precision of a previously unknown one dimensional ball array and the precision of a device being tested after a single measurement step, allowing a calibration process to be performed easily. In addition, this calibration device does not need periodic calibration according to the stringent national standards for volume and value; instead, immediate examination demarcation prior to use performed by each department with its own measurement standard and simple devices will suffice; therefore, long term stability of the calibration device is not required, lowering the manufacture and design standards of the calibration device. This invention not only can be used to calibrate and measure the precision of a three-dimensional coordinate measurement machine, but also can be used in one-, two- or three- dimensional linear motion device having a spatial probe; in addition, it is applicable to the detection and calibration of other devices and precision machinery. With this invention, the automatic calibration device offers advantages of high precision, wide calibration range, utility, real-time, and low production cost, and has a very high applicable value to domestic and oversea industries.