Utilities Alignment Box

[ProbFlex]

how did you make it easy for yourself to help you remember how to best use the Level, Rotate, and Origin? also, when aligning a round part is it a must to rotate for best results?

[DAN_M]

All of my parts come with blueprints that are fully defined with tolerances and datum structures. That being said, I never make my own decisions. Writing a correct program isn't about remembering steps on how to do it.. its about knowing how to interpret the information on the print... and then translate that to PC DMIS's coding language so you output what your customer needs to see.

Do you have a print with datums/any info specific to this part that would help us help you in a more precise way? Do you have a Datum -A- or Datum -B-? Or a defined ZERO point on your print or something?

In general, I could walk you through how to make a plane/circle alignment if you want..?

[DAN_M]

Regarding controlling rotation..it is not necessary.

However, if you are doing anything other than measuring some diameter sizes, I HIGHLY SUGGEST that you DO control rotation. ESPECIALLY if you are going to use the alignment as a base alignment and then offset FROM that alignment. In that scenario, things WILL go bad if you don't rotationally constrain all six degrees of freedom.

At the beginning of your program while recalling startup alignment, CONSTRUCT a LINE, select "ALIGNMENT" in the dropdown box that appears, then press OK. The line will now be in your edit window. I overrode the vector of the line to be X+ (1,0,0) for this example, put it however you need it to be to suit your example. Use this line for rotation as shown. If you F9 my alignment, the trihedron isn't wiggling around like yours would be (meaning all 6 DOF are constrained to PC DMIS).

LIN_XP =FEAT/LINE,CARTESIAN,UNBOUNDED,NO
THEO/<-0.5,0,0>,<1,0,0>
ACTL/<-0.5,0,0>,<1,0,0>
CONSTR/LINE,ALIGN,1,XPLUS
PLN1 =FEAT/CONTACT/PLANE/DEFAULT,CARTESIAN,NONE,LEAST_SQR
THEO/<9.4567,-0.8591,2.2292>,<0,0,1>
ACTL/<9.4567,-0.8591,2.2292>,<0,0,1>
TARG/<9.4567,-0.8591,2.2292>,<0,0,1>
ANGLE VEC=<1,0,0>,RADIAL
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
CIR2 =FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<8.6702,-0.237,0.601>,<0,0,1>,2.7557
ACTL/<8.6702,-0.237,0.601>,<0,0,1>,2.7557
TARG/<8.6702,-0.237,0.601>,<0,0,1>
START ANG=0,END ANG=360
ANGLE VEC=<0.9961947,0,-0.0871557>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
A9 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_XP,ABOUT,ZPLUS
ALIGNMENT/TRANS,XAXIS,CIR2
ALIGNMENT/TRANS,YAXIS,CIR2
ALIGNMENT/TRANS,ZAXIS,PLN1
ALIGNMENT/END

[vpt.se]

For that disc in your picture, I'd just use a plane for level and zero and then a circle for zeroing the other two axises. Works fine and is a fast setup.

[ProbFlex]

I don't have Datums. from the print i am using item 1, machine surface as YPLUS. and putting READ POINT in the center of Item 3.
to stat a alignment using Item 1 as plan YPLUS, Item 3 X,Z origin.

Q: when using a read point; do i need a alignment to still teach the machine to the part and and a another alignment for measurements?

notice the trihedron is at the top of the part. that's how it came. i like it in the center of Item 3. part is sitting upright on the plate on a fixture as the picture shows. the trihedron in the picture is exactly how its sitting on the machine. hope that makes sense.

[DAN_M]

Read point question--> Oh heck yes. The read point, once made into an XYZ alignment, is saying to PC DMIS "that this active probe position is X0Y0Z0". This just gets you started. Its up to you to program in the rest (find the part for real using CNC touches, then create an alignment you want to use, then measure the part).

Translating your trihedron when you have an assembly of CAD stuff in PC DMIS--> Edit/Graphic Display Window/CAD Assembly. Right click on the item in the design tree you want to move, select "Transform" from the dropdown box. Once the "Transformation Dialogue Box" appears, use this window to translate and/or rotate this particular item of your CAD assembly. I use a CMM that has a grid plate, I use external alignments and program with all the CAD just like you. I always import my grid plate and then TRANSLATE it so the trihedron is at the Y-X- corner. Then I put my CAD on top of it where it should be (where it will ultimately be on the CMM in real life). I would then create a program that recalls an external alignment that is tied to my fixture plate, go straight into DCC mode, measure the plane and then the circle, then make a fully defined XYZ alignment used he above referenced methodology

[DAN_M]

Here is a part I am working on now with the code (part pic itself has been suppressed for confidentiality reasons but I can show you the fixture and the beginning of my code)

WORKPLANE/YMINUS
MODE/DCC
RECALL/ALIGNMENT,EXTERNAL,7107_PLATE_ALIGN
LIN_THEO_XP_POS1=FEAT/LINE,CARTESIAN,UNBOUNDED,YES
THEO/<-0.5,0,0>,<1,0,0>
ACTL/<-0.5,0,0>,<1,0,0>
CONSTR/LINE,ALIGN,1,XPLUS
LIN_THEO_YP_POS1=FEAT/LINE,CARTESIAN,UNBOUNDED,NO
THEO/<0,-0.5,0>,<0,1,0>
ACTL/<0,-0.5,0>,<0,1,0>
CONSTR/LINE,ALIGN,1,YPLUS
PNT_ORI_PLATE_POS1=FEAT/POINT,CARTESIAN,NO
THEO/<0,0,0>,<0,-1,0>
ACTL/<0,0,0>,<0,-1,0>
CONSTR/POINT,ORIGIN
RP_CHECKZ_POS1=FEAT/POINT,CARTESIAN
THEO/<0*1,0*1,22*1>,<0,-1,0>
ACTL/<0,0,22>,<0,-1,0>
READPOINT/
MOVE/INCREMENT,<0,0,22-RP_CHECKZ_POS1.Z>
CLEARP/YMINUS,10,YMINUS,10,ON
PLN_Y1_POS1=FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<15.3942,11.6159,9.6643>,<0,-1,0>
ACTL/<15.3942,11.6159,9.6643>,<0,-1,0>
MEAS/PLANE,3
MOVE/CLEARPLANE
HIT/BASIC,NORMAL,<15.6065,11.6159,11.1021>,<0,-1,0>,<15.1644,11.6159,11.0744>,USE THEO=YES
HIT/BASIC,NORMAL,<16.6631,11.6159,9.6874>,<0,-1,0>,<16.1642,11.6159,9.6097>,USE THEO=YES
HIT/BASIC,NORMAL,<13.9129,11.6159,8.2035>,<0,-1,0>,<13.403,11.6159,8.2133>,USE THEO=YES
ENDMEAS/
A1 =ALIGNMENT/START,RECALL:7107_PLATE_ALIGN,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_Y1_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_THEO_XP_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,PNT_ORI_PLATE_POS1
ALIGNMENT/TRANS,YAXIS,PLN_Y1_POS1
ALIGNMENT/TRANS,ZAXIS,PNT_ORI_PLATE_POS1
ALIGNMENT/END
CLEARP/YMINUS,PLN_Y1_POS1.Y-1,YMINUS,PLN_Y1_POS1.Y-1,ON
MOVE/CLEARPLANE
CIRXZ1_POS1=FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<14.9452,0.12,9.4526>,<0,-1,0>,2.7557
ACTL/<14.9452,0.12,9.4526>,<0,-1,0>,2.7557
TARG/<14.9452,0.12,9.4526>,<0,-1,0>
START ANG=0,END ANG=360
ANGLE VEC=<1,0,0>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
A2 =ALIGNMENT/START,RECALL:A1,LIST=YES
ALIGNMENT/TRANS,XAXIS,CIRXZ1_POS1
ALIGNMENT/TRANS,ZAXIS,CIRXZ1_POS1
ALIGNMENT/END
CIRXZ2_POS1=FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<0,0.12,0>,<0,-1,0>,2.7557
ACTL/<0,0.12,0>,<0,-1,0>,2.7557
TARG/<0,0.12,0>,<0,-1,0>
START ANG=-120,END ANG=240
ANGLE VEC=<1,0,0>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
A3 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_Y1_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_THEO_XP_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CIRXZ2_POS1
ALIGNMENT/TRANS,YAXIS,PLN_Y1_POS1
ALIGNMENT/TRANS,ZAXIS,CIRXZ2_POS1
ALIGNMENT/END
MOVE/CLEARPLANE
CIRXZ3_POS1=FEAT/CONTACT/CIRCLE/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<2.5048,0.12,2.3724>,<0,-1,0>,2.9526
ACTL/<2.5048,0.12,2.3724>,<0,-1,0>,2.9526
TARG/<2.5048,0.12,2.3724>,<0,-1,0>
START ANG=0,END ANG=360
ANGLE VEC=<1,0,0>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
LIN_ROUGH_XZ_CLK_POS1=FEAT/LINE,CARTESIAN,UNBOUNDED,NO
THEO/<0,0.12,0>,<1,0,0>
ACTL/<0,0.12,0>,<1,0,0>
CONSTR/LINE,OFFSET
SURFACE NORMAL = <0,-1,0>,MULTI POINT
ID = CIRXZ2_POS1,CIRXZ3_POS1,,
OFFSET = 0,-2.3724
A4 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_Y1_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_ROUGH_XZ_CLK_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CIRXZ2_POS1
ALIGNMENT/TRANS,YAXIS,PLN_Y1_POS1
ALIGNMENT/TRANS,ZAXIS,CIRXZ2_POS1
ALIGNMENT/END
GRP_PNTS_PLN_A_POS1=GROUP/SHOWALLPARAMS=NO
ENDGROUP/ID=GRP_PNTS_PLN_A_POS1
PLN_A_POS1 =FEAT/PLANE,CARTESIAN,TRIANGLE,YES,LEAST_SQR
THEO/<-2.5296,0.8591,2.6412>,<0,-1,0>
ACTL/<-2.5296,0.8591,2.6412>,<0,-1,0>
CONSTR/PLANE,BF,PNTA1_POS1,PNTA2_POS1,PNTA3_POS1,PNTA4_PO S1,PNTA5_POS1,PNTA6_POS1,PNTA7_POS1,PNTA8_POS1,,
OUTLIER_REMOVAL/OFF,3
FILTER/OFF,WAVELENGTH=0
A5 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_A_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_ROUGH_XZ_CLK_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CIRXZ2_POS1
ALIGNMENT/TRANS,YAXIS,PLN_A_POS1
ALIGNMENT/TRANS,ZAXIS,CIRXZ2_POS1
ALIGNMENT/END
CLEARP/YMINUS,PLN_A_POS1.Y-1.75,YMINUS,PLN_A_POS1.Y-1.75,ON
MOVE/CLEARPLANE
CYL_B_POS1 =FEAT/CONTACT/CYLINDER/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<3.2048,0.2756,-0.8276>,<0,-1,0>,0.3143,-0.2559
ACTL/<3.2048,0.2756,-0.8276>,<0,-1,0>,0.3143,-0.2559
TARG/<3.2048,0.2756,-0.8276>,<0,-1,0>
START ANG=0,END ANG=360
ANGLE VEC=<-1,0,0>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
PNT_B_POS1 =FEAT/POINT,CARTESIAN,NO
THEO/<3.2048,0.2756,-0.8276>,<0,-1,0>
ACTL/<3.2048,0.2756,-0.8276>,<0,-1,0>
CONSTR/POINT,CAST,CYL_B_POS1
A6 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_A_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_ROUGH_XZ_CLK_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CYL_B_POS1
ALIGNMENT/TRANS,YAXIS,PLN_A_POS1
ALIGNMENT/TRANS,ZAXIS,CYL_B_POS1
ALIGNMENT/END
MOVE/CLEARPLANE
CYL_C_POS1 =FEAT/CONTACT/CYLINDER/DEFAULT,CARTESIAN,IN,LEAST_SQR
THEO/<-11.9,0.0197,4.1>,<0,1,0>,0.3143,-0.7068
ACTL/<-11.9,0.0197,4.1>,<0,1,0>,0.3143,-0.7068
TARG/<-11.9,0.0197,4.1>,<0,1,0>
START ANG=0,END ANG=360
ANGLE VEC=<1,0,0>
DIRECTION=CCW
SHOW FEATURE PARAMETERS=NO
SHOW CONTACT PARAMETERS=NO
PNT_C_POS1 =FEAT/POINT,CARTESIAN,NO
THEO/<-11.9,0.0197,4.1>,<0,1,0>
ACTL/<-11.9,0.0197,4.1>,<0,1,0>
CONSTR/POINT,CAST,CYL_C_POS1
ALI_AB_POS1=ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_A_POS1
ALIGNMENT/ROTATE,XPLUS,TO,LIN_THEO_XP_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CYL_B_POS1
ALIGNMENT/TRANS,YAXIS,PLN_A_POS1
ALIGNMENT/TRANS,ZAXIS,CYL_B_POS1
ALIGNMENT/END
LIN_ABC_POS1=FEAT/LINE,CARTESIAN,UNBOUNDED,NO
THEO/<0,0.1476,0>,<-1,0,0>
ACTL/<0,0.1476,0>,<-1,0,0>
CONSTR/LINE,OFFSET
SURFACE NORMAL = <0,-1,0>,MULTI POINT
ID = PNT_B_POS1,PNT_C_POS1,,
OFFSET = 0,4.1
ALI_ABC_POS1=ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,YMINUS,PLN_A_POS1
ALIGNMENT/ROTATE,XMINUS,TO,LIN_ABC_POS1,ABOUT,YMINUS
ALIGNMENT/TRANS,XAXIS,CYL_B_POS1
ALIGNMENT/TRANS,YAXIS,PLN_A_POS1
ALIGNMENT/TRANS,ZAXIS,CYL_B_POS1
ALIGNMENT/END

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