US 12,392,605 B2
Method of estimating uncertainty of coordinate measurement
Takeshi Hagino, Kanagawa (JP)
Assigned to MITUTOYO CORPORATION, Kanagawa (JP)
Filed by MITUTOYO CORPORATION, Kanagawa (JP)
Filed on Oct. 17, 2022, as Appl. No. 17/967,128.
Claims priority of application No. 2021-173421 (JP), filed on Oct. 22, 2021.
Prior Publication US 2023/0127538 A1, Apr. 27, 2023
Int. Cl. G01B 21/04 (2006.01)
CPC G01B 21/045 (2013.01) 4 Claims
OG exemplary drawing
 
1. An uncertainty estimation method conducted by a processor, which is an uncertainty estimation method for estimating measurement uncertainty of a coordinate measuring machine, comprising:
acquiring a plurality of first variable values A1 and K1, included in a function E=±(A+D/K) indicating a relationship between a measurement dimension and a maximum permissible length measurement error, where A represents an intercept at the measurement dimension 0 of a function indicating the relationship between the measurement dimension of the coordinate measuring machine and the maximum permissible length measurement error, 1/K represents a proportionality coefficient of a measurement error, and D represents a distance between two points on the object to be measured, when a ram axis stylus tip offset of the coordinate measuring machine or an operating environment of the coordinate measuring machine is a first value, and a plurality of second variable values A2 and K2, included in the function when the ram axis stylus tip offset is a second value;
calculating a maximum permissible length measurement error corresponding to a third value by calculating the plurality of variable values of the function, A3 and K3, occurring when the ram axis stylus tip offset is the third value, by interpolation or extrapolation on the basis of the A1 and K1 occurring when the ram axis stylus tip offset is the first value and the A2 and K2 occurring when the ram axis stylus tip offset is the second value;
estimating the measurement uncertainty of the coordinate measuring machine on the basis of the calculated maximum permissible length measurement error; and
controlling a measuring mechanism of the coordinate measuring machine to execute measurement by the coordinate measuring machine when the estimated uncertainty is less than a predetermined threshold and to stop the measurement by the coordinate measuring machine when the estimated uncertainty is equal to or greater than the predetermined threshold.