Methods of calibrating a measuring device

Abstract

A measuring device is provided with a laser source, a beam redirection member, a beam receptor, and a system controller. The measuring device is calibrated by providing a set-up piece having at least one known dimension and positioning the beam redirection member in beam transmitting relationship to the known dimension of the set-up piece. A beam is transmitted from the laser source to the set-up piece via the beam redirection member, which beam is reflected back to the beam receptor via the beam redirection member. The return beam is converted into data, which is transmitted to the system controller. The data is used to calculate a measured dimension, and a compensation factor based on the measured dimension and the known dimension of the set-up piece is then calculated.

1 - 10 . (canceled) 
   
   
       11 . In a measuring device comprising a laser source, a beam redirection member in beam receiving relationship to the laser source, a beam receptor adapted to receive a return beam from the beam redirection member and convert the return beam into data, and a system controller adapted to receive and process the data from the beam receptor, the improvement comprising a method of calibrating the measuring device comprising the steps of:
 providing a set-up piece having at least one known dimension;   positioning the beam redirection member in beam transmitting relationship to the known dimension of the set-up piece;   transmitting a beam from the laser source to the beam redirection member;   transmitting the beam from the beam redirection member to the set-up piece;   reflecting a return beam from the set-up piece to the beam redirection member;   transmitting the return beam from the beam redirection member to the beam receptor;   converting the return beam into data;   transmitting the data to the system controller;   calculating a measured dimension using the data; and   calculating a compensation factor based on the measured dimension and the known dimension of the set-up piece.   
   
   
       12 . The method of  claim 11  wherein the step of positioning the beam redirection member includes providing the measuring device with a platform adapted to support the set-up piece and a platform drive system adapted for moving the platform with respect to the beam redirection member, and further includes the steps of:
 positioning the set-up piece on the platform; and   actuating the platform drive system to move the platform to a predetermined position with respect to the beam redirection member.   
   
   
       13 . The method of  claim 12  wherein the step of transmitting a beam from the laser source to the beam redirection member includes transmitting the beam vertically downward, the step of said transmitting the beam from the beam redirection member to the set-up piece includes transmitting the beam in a horizontal direction, and the step of positioning the beam redirection member in beam transmitting relationship to the known dimension of the set-up piece includes moving the beam redirection member downwardly and into beam transmitting relationship to the known dimension of the set-up piece. 
   
   
       14 . The method of  claim 11  wherein the steps of providing a set-up piece, positioning the beam redirection member, transmitting a beam from the laser source to the beam redirection member, transmitting the beam from the beam redirection member to the set-up piece, reflecting a return beam from the set-up piece to the beam redirection member, transmitting the return beam from the beam redirection member to the beam receptor, converting the return beam into data, transmitting the data to the system controller, calculating a measured dimension using the data, and calculating a compensation factor are performed sequentially. 
   
   
       15 . The method of  claim 14  further comprising the steps of:
 providing the measuring device with a platform adapted to support the set-up piece and a platform drive system adapted for moving the platform with respect to the beam redirection member and including a motor and an encoder;   determining the location of the center of the platform;   defining a horizontal axis passing through the center of the platform;   actuating the platform drive system to move the platform toward the beam redirection member, thereby positioning the center of the platform directly below the beam redirection member; and   operating the encoder to record the position of the motor, thereby defining a measurement position,   wherein the steps of providing the measuring device with a platform and a platform drive system, determining the location of the center of the platform, defining a horizontal axis passing through the center of the platform, actuating the platform drive system to move the platform toward the beam redirection member, and operating the encoder to record the position of the motor are performed prior to the step of providing a set-up piece.   
   
   
       16 . The method of  claim 11  wherein the step of calculating a compensation factor includes calculating a compensation factor based on a plurality of measured dimensions and corresponding known dimensions of the set-up piece. 
   
   
       17 . In a measuring device comprising a laser head adapted to transmit a beam along a vertical Y-axis and to receive a return beam and convert the return beam into a distance measurement, a beam redirection member in beam receiving relationship to the laser head and adapted to direct the beam along a Z-axis perpendicular to the Y-axis, a system controller adapted to receive and process the distance measurement from the laser head, a primary drive system adapted to move the beam redirection member along the Y-axis, a platform adapted to support a set-up piece, and a platform drive system adapted to move the platform along the Z-axis, the improvement comprising a method of calibrating the measuring device comprising the steps of:
 providing a cylindrical set-up piece having a central axis and a known inner radius;   positioning the set-up piece on the platform such that the central axis of the set-up piece is vertical and aligned with the center of the platform;   actuating the platform drive system to position the center of the platform on the Y-axis, thereby substantially aligning the central axis of the set-up piece and the Y-axis;   actuating the primary drive system to move the beam redirection member along the Y-axis and into beam transmitting relationship to the inner radius of the set-up piece;   transmitting a beam from the laser head to the beam redirection member;   transmitting the beam from the beam redirection member to the set-up piece;   reflecting a return beam from the set-up piece to the beam redirection member and from there to the laser head which calculates a measured distance using the return beam;   transmitting the measured distance to the system controller; and   calculating a compensation factor based on the measured distance and the known inner radius of the set-up piece.   
   
   
       18 . The method of  claim 17  wherein the steps of providing a set-up piece, positioning the set-up piece on the platform, actuating the platform drive system, actuating the primary drive system, transmitting a beam from the laser source to the beam redirection member, transmitting the beam from the beam redirection member to the set-up piece, reflecting a return beam from the set-up piece to the beam redirection member, transmitting the measured distance to the system controller, and calculating a compensation factor are performed sequentially. 
   
   
       19 . The method of  claim 18  further comprising:
 providing the platform drive system with a motor and an encoder;   determining the location of the center of the platform;   defining a horizontal X-axis passing through the center of the platform and perpendicular to the Z-axis;   actuating the platform drive system to move the platform along the Z-axis, thereby causing the Y-axis to intersect the horizontal X-axis; and   operating the encoder to record the position of the motor, thereby defining a measurement position,   wherein the steps of providing the platform drive system with a motor and an encoder, determining the location of the center of the platform, defining a horizontal axis passing through the center of the platform, actuating the platform drive system to move the platform along the Z-axis, and operating the encoder to record the position of the motor are performed prior to the step of providing a set-up piece.