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Parallelism calculation

Hello everyone !
Our client asked us a question about how we calculate parallelism, according to what formula. At the beginning, I wanted to say that our software is doing this for which we pay a lot of money, so that it would do it for us, but now I myself became interested in how it works under the hood. Can anyone explain to the realties how the formula is the calculation of the parallelism between two planes. I also have ISO 1101 on my hands and I did not find the exact method there.
Below I will give the code of the program in which the method of obtaining the result 0.017 is interesting

PLN1 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<236.481,648.717,-585.265>,<0.0085387,0.0007208,0.9999633>
ACTL/<226.667,647.285,-585.263>,<-0.0024375,-0.0020112,0.999995>
MEAS/PLANE,3
HIT/BASIC,NORMAL,<223.821,649.127,-585.157>,<0.0085387,0.0007208,0.9999633>,<240.328, 645.259,-585.234>,USE THEO=YES
HIT/BASIC,NORMAL,<241.462,652.75,-585.31>,<0.0085387,0.0007208,0.9999633>,<217.665,6 45.262,-585.289>,USE THEO=YES
HIT/BASIC,NORMAL,<244.162,644.275,-585.327>,<0.0085387,0.0007208,0.9999633>,<222.007, 651.335,-585.267>,USE THEO=YES
ENDMEAS/
CIR1 =FEAT/CIRCLE,CARTESIAN,IN,LEAST_SQR
THEO/<233.809,649.084,-583.931>,<0,0,1>,13.401
ACTL/<231.62,650.96,-585.217>,<0,0,1>,12.398
MEAS/CIRCLE,4,ZPLUS
HIT/BASIC,NORMAL,<227.179,648.069,-583.931>,<0.9884871,0.1513048,0>,<225.428,651.273,-585.217>,USE THEO=YES
HIT/BASIC,NORMAL,<240.439,648.075,-583.93>,<-0.9886135,0.1504771,0>,<237.812,651.273,-585.217>,USE THEO=YES
HIT/BASIC,NORMAL,<233.212,655.753,-583.931>,<0.0891369,-0.9960194,0>,<232.463,657.101,-585.217>,USE THEO=YES
HIT/BASIC,NORMAL,<233.208,642.418,-583.93>,<0.08987,0.9959535,0>,<232.466,644.82,-585.217>,USE THEO=YES
ENDMEAS/
A1 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN1
ALIGNMENT/TRANS,ZAXIS,PLN1
ALIGNMENT/TRANS,XAXIS,CIR1
ALIGNMENT/TRANS,YAXIS,CIR1
ALIGNMENT/END
MODE/DCC
CLEARP/ZPLUS,20,ZPLUS,20,ON
MOVESPEED/ 60
PLN2 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<0.059,0.464,0.007>,<0,0,1>
ACTL/<0.058,0.466,0.006>,<0.0005612,-0.0005872,0.9999997>
MEAS/PLANE,4
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<-9.257,6.82,0.015>,<0,0,1>,<-9.258,6.822,0.02>,USE THEO=YES
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<9.899,6.82,0.012>,<0,0,1>,<9.899,6.8 22,-0.001>,USE THEO=YES
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<9.899,-5.892,0.002>,<0,0,1>,<9.897,-5.891,0.001>,USE THEO=YES
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<-10.305,-5.892,-0.001>,<0,0,1>,<-10.306,-5.89,0.003>,USE THEO=YES
MOVE/CLEARPLANE
ENDMEAS/
A2 =ALIGNMENT/START,RECALL:A1,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN2
ALIGNMENT/TRANS,ZAXIS,PLN2
ALIGNMENT/END
CIR2 =FEAT/CIRCLE,CARTESIAN,IN,LEAST_SQR
THEO/<-0.031,-0.003,0.5>,<0,0,1>,12.543
ACTL/<0.007,-0.011,0.5>,<0,0,1>,12.549
MEAS/CIRCLE,4,ZPLUS
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<-6.037,-1.818,0.462>,<0.9572437,0.2892827,0>,<-6.012,-1.8,0.462>,USE THEO=YES
HIT/BASIC,NORMAL,<5.976,-1.819,0.533>,<-0.9571949,0.2894442,0>,<6.019,-1.832,0.533>,USE THEO=YES
HIT/BASIC,NORMAL,<1.032,-6.178,0.504>,<-0.1696218,0.9855092,0>,<1.016,-6.196,0.505>,USE THEO=YES
HIT/BASIC,NORMAL,<1.032,6.176,0.501>,<-0.1695347,-0.9855242,0>,<1.015,6.178,0.5>,USE THEO=YES
ENDMEAS/
A3 =ALIGNMENT/START,RECALL:A2,LIST=YES
ALIGNMENT/TRANS,XAXIS,CIR2
ALIGNMENT/TRANS,YAXIS,CIR2
ALIGNMENT/END
MOVE/POINT,NORMAL,<-0.871,1.766,136.539>
TIP/T1A-90B90, SHANKIJK=1, 0, 0.009, ANGLE=89.978
MOVE/POINT,NORMAL,<40.740,7.080,12.618>
MOVE/POINT,NORMAL,<33.116,4.412,-10.804>
PNT1 =FEAT/POINT,CARTESIAN
THEO/<-5.548,7.753,-0.708>,<0,0,-1>
ACTL/<-5.549,7.753,-0.708>,<0,0,-1>
MEAS/POINT,1,WORKPLANE
HIT/BASIC,NORMAL,<-5.548,7.753,-0.708>,<0,0,-1>,<-5.549,7.753,-0.708>,USE THEO=YES
ENDMEAS/
PNT2 =FEAT/POINT,CARTESIAN
THEO/<-5.556,-6.197,-0.709>,<0,0,-1>
ACTL/<-5.556,-6.194,-0.714>,<0,0,-1>
MEAS/POINT,1,WORKPLANE
HIT/BASIC,NORMAL,<-5.556,-6.197,-0.709>,<0,0,-1>,<-5.556,-6.194,-0.714>,USE THEO=YES
ENDMEAS/
PNT3 =FEAT/POINT,CARTESIAN
THEO/<11.024,-6.197,-0.703>,<0,0,-1>
ACTL/<11.025,-6.197,-0.703>,<0,0,-1>
MEAS/POINT,1,WORKPLANE
HIT/BASIC,NORMAL,<11.024,-6.197,-0.703>,<0,0,-1>,<11.025,-6.197,-0.703>,USE THEO=YES
ENDMEAS/
PNT4 =FEAT/POINT,CARTESIAN
THEO/<11.025,6.635,-0.701>,<0,0,-1>
ACTL/<11.026,6.636,-0.719>,<0,0,-1>
MEAS/POINT,1,WORKPLANE
HIT/BASIC,NORMAL,<11.025,6.635,-0.701>,<0,0,-1>,<11.026,6.636,-0.719>,USE THEO=YES
ENDMEAS/
PLN3 =FEAT/PLANE,CARTESIAN,TRIANGLE,YES
THEO/<2.735,0.498,-0.7>,<0,0,-1>
ACTL/<2.736,0.5,-0.711>,<-0.0000149,-0.000364,-0.9999999>
CONSTR/PLANE,BFRE,PNT1,PNT2,PNT3,PNT4,,
OUTLIER_REMOVAL/OFF,3
FILTER/OFF,WAVELENGTH=0
MOVE/POINT,NORMAL,<31.787,6.633,-4.375>
MOVE/POINT,NORMAL,<31.251,6.757,194.900>
TIP/T1A0B0, SHANKIJK=-0.003, 0.001, 1, ANGLE=0
COMMENT/REPT,
Distance 0.7 ±0.01
DIM LOC1= LOCATION OF PLANE PLN3 UNITS=MM ,$
GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH HALF ANGLE=NO
AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
Z -0.700 0.030 0.030 -0.711 -0.011 0.000 --#------
END OF DIMENSION LOC1
COMMENT/REPT,
Parallelism 0.02
DIM PARL1= PARALLELISM OF PLANE PLN3,RFS TO WORKPLANE ZPLUS UNITS=MM ,$
GRAPH=OFF TEXT=OFF MULT=10.00 OUTPUT=BOTH
AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
M 0.000 0.020 0.000 0.017 0.017 0.000 -------#-
DIM FLAT4= FLATNESS OF PLANE PLN2 UNITS=MM ,$
GRAPH=OFF TEXT=OFF MULT=10.00 ARROWDENSITY=100 OUTPUT=BOTH
AX NOMINAL +TOL -TOL MEAS DEV OUTTOL
M 0.000 0.200 0.000 0.010 0.010 0.000 #--------
Parents
  • It's the difference between max and min dot product of the COP to the reference.
    ASSIGN/V1=DOT(PLN1.HIT[1..PLN1.NUMHITS].XYZ-PLN_REF.XYZ,PLN_REF.IJK)
    ASSIGN/PARAL=ABS(MAX(V1)-MIN(V1))

    The flatness of PLN1 is included in the parallelism.
    ISO1101 :

    Parallelism indication

    The tolerance zone defined by the specification in Figure 112 is limited by two parallel planes a distance t apart.
    The planes are parallel to the datums and in the direction specified.


    What does the COP mean?
Reply
  • It's the difference between max and min dot product of the COP to the reference.
    ASSIGN/V1=DOT(PLN1.HIT[1..PLN1.NUMHITS].XYZ-PLN_REF.XYZ,PLN_REF.IJK)
    ASSIGN/PARAL=ABS(MAX(V1)-MIN(V1))

    The flatness of PLN1 is included in the parallelism.
    ISO1101 :

    Parallelism indication

    The tolerance zone defined by the specification in Figure 112 is limited by two parallel planes a distance t apart.
    The planes are parallel to the datums and in the direction specified.


    What does the COP mean?
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