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Tertiary Datum doesn't constrain any degrees of freedom?

2023.1--Selecting Datum A as a plane; Datum B as a hole, Datum C as a hole.
"GEOMAJIC" States Datum C doesn't control any degree of freedom
Without Datum C, Datum B doesn't constrain the final degree of rotational freedom.
Am I wrong here?
Parents
  • This one has me really stumped:

    DATDEF/A,FEATURES=PLN_A,,
    DATDEF/B,FEATURES=PLN_B,,
    DATDEF/C,FEATURES=LIN_C,,

    PLN_A        =FEAT/PLANE,CARTESIAN,OUTLINE,NO,LEAST_SQR
                  THEO/<-0.420649,0.718,9.894943>,<0,-1,0>
                  ACTL/<-0.420649,0.718,9.894943>,<0,-1,0>
                  CONSTR/PLANE,BF,PNT_A1,PNT_A2,PNT_A3,PNT_A4,PNT_A6,PNT_A7,PNT_A8,PNT_A9,PNT_A10,PNT_A11,PNT_A12,PNT_A13,PNT_A14,PNT_A15,PNT_A17,PNT_A18,PNT_A19,PNT_A20,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0
    PLN_B        =FEAT/PLANE,CARTESIAN,OUTLINE,NO,LEAST_SQR
                  THEO/<0,-0.343,9.760499>,<-1,0,0>
                  ACTL/<0,-0.343,9.760499>,<-1,0,0>
                  CONSTR/PLANE,BF,PNT_B1,PNT_B2,PNT_B3,PNT_B4,PNT_B5,PNT_B6,PNT_B7,PNT_B8,PNT_B9,PNT_B10,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0    
    PNT_C1       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=SURFACE
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.19685,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.15,DISTANCE AFTER=0.15,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    PNT_C2       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=BOTH
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.3,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.25,DISTANCE AFTER=0.25,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    PNT_C3       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=BOTH
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.3,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.25,DISTANCE AFTER=0.25,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    LIN_C        =FEAT/LINE,CARTESIAN,UNBOUNDED,NO
                  THEO/<0.252386,-0.718,0>,<1,0,0>
                  ACTL/<0.252386,-0.718,0>,<1,0,0>
                  CONSTR/LINE,BF,2D,PNT_C1,PNT_C2,PNT_C3,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0              
    Even though LIN_C is in the direction of X+ it should still be the origin for Z axis.

    But according to 2023.1, it doesn't constrain any degrees of freedom.

    "Datum is invalid because it constrains no degrees of freedom. Datum reference C"

    But since it is and Edge it will constrain the last degree of freedom

Reply
  • This one has me really stumped:

    DATDEF/A,FEATURES=PLN_A,,
    DATDEF/B,FEATURES=PLN_B,,
    DATDEF/C,FEATURES=LIN_C,,

    PLN_A        =FEAT/PLANE,CARTESIAN,OUTLINE,NO,LEAST_SQR
                  THEO/<-0.420649,0.718,9.894943>,<0,-1,0>
                  ACTL/<-0.420649,0.718,9.894943>,<0,-1,0>
                  CONSTR/PLANE,BF,PNT_A1,PNT_A2,PNT_A3,PNT_A4,PNT_A6,PNT_A7,PNT_A8,PNT_A9,PNT_A10,PNT_A11,PNT_A12,PNT_A13,PNT_A14,PNT_A15,PNT_A17,PNT_A18,PNT_A19,PNT_A20,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0
    PLN_B        =FEAT/PLANE,CARTESIAN,OUTLINE,NO,LEAST_SQR
                  THEO/<0,-0.343,9.760499>,<-1,0,0>
                  ACTL/<0,-0.343,9.760499>,<-1,0,0>
                  CONSTR/PLANE,BF,PNT_B1,PNT_B2,PNT_B3,PNT_B4,PNT_B5,PNT_B6,PNT_B7,PNT_B8,PNT_B9,PNT_B10,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0    
    PNT_C1       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<0.252386,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=SURFACE
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.19685,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.15,DISTANCE AFTER=0.15,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    PNT_C2       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<0.782489,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=BOTH
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.3,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.25,DISTANCE AFTER=0.25,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    PNT_C3       =FEAT/CONTACT/EDGE POINT/DEFAULT,CARTESIAN
                  THEO/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  ACTL/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  TARG/<1.44509,-0.718,0>,<0,0,-1>,<0,-1,0>
                  MEASURE ORDER=BOTH
                  SHOW FEATURE PARAMETERS=NO
                  SHOW CONTACT PARAMETERS=YES
                    DEPTH=0.015
                    SAMPLE HITS=1,SPACER=0.3,INDENT1=0.15
                    AVOIDANCE MOVE=BOTH,DISTANCE BEFORE=0.25,DISTANCE AFTER=0.25,DIRECTION=ALONG FEATURE VECTOR
                    ONERROR=NO
    LIN_C        =FEAT/LINE,CARTESIAN,UNBOUNDED,NO
                  THEO/<0.252386,-0.718,0>,<1,0,0>
                  ACTL/<0.252386,-0.718,0>,<1,0,0>
                  CONSTR/LINE,BF,2D,PNT_C1,PNT_C2,PNT_C3,,
                  OUTLIER_REMOVAL/OFF,3
                  FILTER/OFF,WAVELENGTH=0              
    Even though LIN_C is in the direction of X+ it should still be the origin for Z axis.

    But according to 2023.1, it doesn't constrain any degrees of freedom.

    "Datum is invalid because it constrains no degrees of freedom. Datum reference C"

    But since it is and Edge it will constrain the last degree of freedom

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