N-21NZX or Y軸150 mm150 mmX or Y軸ZXYCoordinate Measuring MachinesQuick Guide to Precision Measuring InstrumentsRegarding the performance assessment method of CMM, a revision of ISO 10360 Series was issued in 2003, and was partially revised in 2009.The following describes the standard inspection method including the revised content. The following error denitions were added in ISO 10360-2: 2009.Note: ISO 10360-2: 2009 requires measurement in 4 different directions and recommends measurement parallel to each axis, while ISO 10360-2: 2001 specied the measurement "in 7 arbitrary directions."Figure 1 Measauring directions to obtain length measurement errorFigure 2 Length measurement error when Z-axis stylus offset is 150 mmFigure 3 Repeating range of length measurementFigure 4 Evaluation of a CMM with a rotary tableTable 1 ISO 10360 SeriesE0,MPE (MPEE) = A + L/K≤BE0,MPE (MPEE) = A + L/KE0,MPE (MPEE) = BA: Constant (µm) specied by the manufacturerK: Dimensionless constant specied by the manufacturerL: Measured length (mm)B: Upper limit value (µm) specied by the manufacturer⎫⎬⎭Performance Assessment Method of Coordinate Measuring MachinesUsing the standard CMM with specied probe, measure 5 different calibrated lengths 3 times each in 7 directions within the measuring volume (as indicated in Figure 1), making a total of 105 measurements.If these measurement results, including the allowance for the uncertainty of measurement, are equal to or less than the values specied by the manufac-turer, then it proves that the performance of the CMM meets its specication.The result of OK/NG is required to be judged considering the uncertainties. The maximum permissible error (standard value) of the test may be expressed in any of the following three forms (unit: µm).In addition to length measurement in 7 directions, ISO 10360-2: 2009 species measuring in 2 lines over the diagonal YZ or XZ plane with probe offset as shown in Figure 2. Note: The stylus offset is set at 150 mm as default.Calculate the maximum value from the results of three repeated measurements.Maximum Permissible Length Measurement Error E0, MPE [ISO 10360-2: 2009]Maximum Permissible Length Measurement Error/ Length Measurement Error when stylus offset is 150 mm E150, MPE [ISO 10360-2: 2009]Maximum Permissible Limit of the Repeatability Range of Length Measurement R0, MPL [ISO 10360- 2: 2009]The test procedure under this standard is to place two standard spheres on the rotary table as shown in Figure 4. Rotate the rotary table to a total of 15 positions including 0˚, 7 positions in the plus (+) direction, and 7 positions in the minus (-) direction and measure the center coordinates of the two spheres in each position. Then, add the uncertainty of the standard sphere shape to each variation (range) of radial direction elements, connecting direction elements, and rotational axis direction elements of the two standard sphere center coordinates. If these calculated values are less than the specied values, the evaluation test is passed.Maximum Permissible Radial Four-Axis Error MPEFR,Maximum Permissible Tangential Four-Axis Error MPEFT, andMaximum Permissible Axial Four-Axis Error MPEFA [ISO 10360-3: 2000]YrXhhAhBSphere BZSphere AItemISO Standard No.Year of issue1TermsISO 10360-120002Length measurementISO 10360-220093Rotary table equipped CMMISO 10360-32000 4Scanning measurementISO 10360-42000 5 Single/Multi-styli measurementISO 10360-520106Software inspectionISO 10360-62001Length meas. error 3（Z）Length meas. error 4Length meas. error 7Length meas. error 5Length meas. error 6Length meas. error 1（X）Length meas. error 2（Y）ZYXZYX6.04.02.00.0-2.0-4.0-6.00123R0200400Measurement length [mm]Error［µm］600800Standard valueThis is the accuracy standard for a CMM if equipped with a scanning probe. The test procedure under this standard is to perform a scanning measurement in 4 planes on the standard sphere and then, for the least squares sphere center calculated using all the measurement points, calculate the radial range (dimension ‘A’ in Figure 5) within which all measurement points exist. Based on the least squares sphere center calculated above, calculate the radial distance between the calibrated standard sphere radius and the maximum measurement point and the minimum measurement point, and take the larger distance (dimension ’B’ in Figure 5). Add an extended uncertainty that combines the uncertainty of the stylus tip shape and the uncertainty of the standard test sphere shape to each A and B dimension. If both calculated values are less than the specied values, this scanning probe test is passed.Maximum Permissible Scanning Probing Error MPETHP [ISO 10360-4: 2000]Figure 5 Target measurement planes for the maximum permissible scanning probing error and its evaluation conceptLeast square sphere centerStylusLeast square sphereMeasurement point locusABCalibrated value ofstandard sphere radiusScan plane 1Scan plane 2Scan plane 3Scan plane 445°
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