Plane Line Line Alignment

[ALousyUser]

I've got two problems:

1. I want to set the lower left corner and the top plane as the origin. The Z plane is fine, but the X and Y origins are in the middle of my hits, which makes sense. However, that's not the origin I'm looking for. How would I be able to create the corner as the origin in all axises and not in the middle? Code/pic below:
2. Why am I seeing the CAD model in 1 place and the picked points in a different space? I guess the better question would be: how can I make the actual PCS match the CAD? I was told something about virtual probe, but I'm not sure how that is going to help because I would be picking points on the CAD model. This wouldn't tell the software exactly where the part actually is on the machine.

forum1.JPG

PLN1 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<513.112,351.382,-682.952>,<0.0021768,-0.001219,0.9999969>
ACTL/<513.112,351.382,-682.952>,<0.0021768,-0.001219,0.9999969>
MEAS/PLANE,3
HIT/BASIC,NORMAL,<488.206,336.927,-682.915>,<0.0021768,-0.001219,0.9999969>,<488.206,336.927,-682.915>,USE THEO=YES
HIT/BASIC,NORMAL,<510.822,379.466,-682.912>,<0.0021768,-0.001219,0.9999969>,<510.822,379.466,-682.912>,USE THEO=YES
HIT/BASIC,NORMAL,<540.309,337.755,-683.027>,<0.0021768,-0.001219,0.9999969>,<540.309,337.755,-683.027>,USE THEO=YES
ENDMEAS/
LIN1 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<485.052,332.731,-685.882>,<0.9999978,0.0020766,0>
ACTL/<485.052,332.731,-685.882>,<0.9999978,0.0020766,0>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<485.052,332.731,-685.879>,<0.0020766,-0.9999978,0>,<485.052,332.731,-685.879>,USE THEO=YES
HIT/BASIC,NORMAL,<549.702,332.865,-685.884>,<0.0020766,-0.9999978,0>,<549.702,332.865,-685.884>,USE THEO=YES
ENDMEAS/
LIN2 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<478.488,340.816,-685.33>,<-0.0021937,0.9999976,0>
ACTL/<478.488,340.816,-685.33>,<-0.0021937,0.9999976,0>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<478.488,340.816,-685.333>,<-0.9999976,-0.0021937,0>,<478.488,340.816,-685.333>,USE THEO=YES
HIT/BASIC,NORMAL,<478.418,372.484,-685.327>,<-0.9999976,-0.0021937,0>,<478.418,372.484,-685.327>,USE THEO=YES
ENDMEAS/
A1 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN1
ALIGNMENT/ROTATE,XPLUS,TO,LIN1,ABOUT,ZPLUS
ALIGNMENT/TRANS,ZAXIS,PLN1
ALIGNMENT/TRANS,XAXIS,LIN1
ALIGNMENT/TRANS,YAXIS,LIN2
ALIGNMENT/END

[Cos_BO]

Hi,
for number 2, I usually start with 1 feature (PLN) and create the first alignment afterwards. Then next feature (LIN) and create a second alignment, based on the first. I am not sure why this is necessary, but this way it works.

[ALousyUser]

Would the first alignment be a simple level and origin of the PLN, or just a level?

[Matthew D. Hoedeman]

I would construct a point at the intersection of the 2 lines and use that. This way, the origin won't wander about as the angle between lines changes. The rotate line will be ZERO the entire length and the corner will be zero. The other line will not be zero along it's length since nothing is perfect.

[ALousyUser]

I see, I'll try that tomorrow. Machine's tied up right now.

[UKCMM]

You need to use LIN 2 as the X translate and LIN1 as the Y translate origin, remember it is a vector direction not an origin

[ALousyUser]

I'm a bit confused. I always thought translating X/Y/Z axises would set them as the origins. Can you elaborate? #inb4 i get told to go take pcdmis classes

[UKCMM]

Yes translating to an axis will lock an origin but an X vector line cannot lock the X origin it will just use the centroid of the line and that will depend on the hit locations none of which will be at the drawing X datum. The same goes for the Y and Z.

[ALousyUser]

I see now UKCMM. Thanks a lot for the explanation.

[Schlag]

The manual alignment tells the machine where the part is on the machine. When you use the virtual probe or program offline from the model, the THEOS for you 1st features are in CAD coordinates. Your features will then overlay on the cad. When you actually run the part thru on the CMM the actuals will switch to machine coordinates. Programming with from the cad is 10x faster than driving the machine around and all your vectors will be flawless. Programming from an actual part incporporates all the error of the part into the program.

[LostL]

Good points here.

[pcdmisstudent]

I've got two problems:

PLN1 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<513.112,351.382,-682.952>,<0.0021768,-0.001219,0.9999969>


LIN1 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<485.052,332.731,-685.882>,<0.9999978,0.0020766,0>    <--- Line points in X+ direction. A line can be infinite long, so you cant lock X-orgin here



LIN2 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<478.488,340.816,-685.33>,<-0.0021937,0.9999976,0>     <--------  Same as above,

A1 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN1
ALIGNMENT/ROTATE,XPLUS,TO,LIN1,ABOUT,ZPLUS
ALIGNMENT/TRANS,ZAXIS,PLN1
ALIGNMENT/TRANS,XAXIS,LIN1                <--------------- transl X to LIN1 should be Y
ALIGNMENT/TRANS,YAXIS,LIN2                <--------------- transl Y to LIN2 should be X
ALIGNMENT/END

This is the answer to your question 2, the elements arent shown on the CAD because you havent aligned the part properly.

Sidenote: Also its a good practice (i think) to measure plane > Level orgin > Measure line > rotate orgin > Measure line > orgin.
And after that i would fine-tune the alignment by increasing points/movespeed etc and do it in this order: Feature > Level > Feature > Rotate > Last feature > Level, rotate, orgin XYZ, give the alignment a name for easier recall. I would also construct intersect.point where LIN1 intersects with LIN2 and orgin YX in that. (like Matthew said)

[ALousyUser]

OK, thank you very much for pointing out exactly where I went wrong. I have already asked UKCMM why the two translates should be reversed. Why?

[ALousyUser]

pcdmisstudent I get it now. Thanks again for taking the time to explain some basic concepts to me. Appreciate it.

[ALousyUser]

When I used to use PCDMIS 2014, my experience would be like this:

- create manual alignment after picking points on the actual part
- CAD snaps to the origin coordinates
- DCC alignment goes by fine because the machine and part coordinates are either pretty close or match

PCDMIS 2018:

- create manual alignments after picking points on the actual part
- CAD does not snap to the machine/origin coordinates
- DCC alignment gives me issues because of the difference between the machine and part coordinates

I tried doing the same as listed directly above, after transforming the CAD to roughly where the probe tip is (near the part). No such luck.

Not knowing why this happens is driving me up a wall if I'm being frank.

PLN1 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<503.75,280.957,-683.17>,<0,0,1>
ACTL/<503.415,283.171,-683.171>,<-0.0002023,0.000432,0.9999999>
MEAS/PLANE,3
HIT/BASIC,NORMAL,<474.932,266.393,-683.17>,<-0.0002077,0.0004325,0.9999999>,<477.1,269.042,-683.17>,USE THEO=YES
HIT/BASIC,NORMAL,<504.663,310.15,-683.183>,<-0.0002077,0.0004325,0.9999999>,<502.607,310.064,-683.183>,USE THEO=YES
HIT/BASIC,NORMAL,<531.656,266.327,-683.158>,<-0.0002077,0.0004325,0.9999999>,<530.539,270.408,-683.16>,USE THEO=YES
ENDMEAS/
LIN1 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<474.658,264.78,-689.038>,<1,0,0>
ACTL/<474.885,264.779,-686.853>,<1,-0.0002959,0>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<474.658,264.78,-689.036>,<-0.0004018,-0.9999999,0>,<474.885,264.779,-687.468>,USE THEO=YES
HIT/BASIC,NORMAL,<532.99,264.756,-689.039>,<-0.0004018,-0.9999999,0>,<535.401,264.761,-686.238>,USE THEO=YES
ENDMEAS/
LIN2 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<466.829,270.946,-688.073>,<0,1,0>
ACTL/<466.825,272.759,-686.949>,<0.0002188,1,0>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<466.829,270.946,-688.069>,<-1,0.0000772,0>,<466.825,272.759,-686.978>,USE THEO=YES
HIT/BASIC,NORMAL,<466.831,301.286,-688.077>,<-1,0.0000772,0>,<466.832,303.176,-686.92>,USE THEO=YES
ENDMEAS/
A1 =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN1
ALIGNMENT/ROTATE,XPLUS,TO,LIN1,ABOUT,ZPLUS
ALIGNMENT/TRANS,ZAXIS,PLN1
ALIGNMENT/TRANS,YAXIS,LIN1
ALIGNMENT/TRANS,XAXIS,LIN2
ALIGNMENT/END
MODE/DCC
PLN2 =FEAT/PLANE,CARTESIAN,TRIANGLE
THEO/<39.912,15.488,34.69>,<0,0,1>
ACTL/<39.913,15.486,34.69>,<-0.0000055,0.0000005,1>
MEAS/PLANE,3
HIT/BASIC,NORMAL,<9.749,3.052,34.69>,<0,0,1>,<9.749,3. 053,34.69>,USE THEO=YES
HIT/BASIC,NORMAL,<38.653,43.671,34.69>,<0,0,1>,<38.657 ,43.67,34.69>,USE THEO=YES
HIT/BASIC,NORMAL,<71.332,-0.26,34.69>,<0,0,1>,<71.332,-0.265,34.69>,USE THEO=YES
ENDMEAS/
LIN3 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<10.171,-2.54,21.114>,<1,0,0>
ACTL/<10.17,-2.538,21.113>,<1,-0.0001059,0.0000055>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<10.171,-2.54,23.284>,<0,-1,0>,<10.17,-2.538,23.284>,USE THEO=YES
HIT/BASIC,NORMAL,<74.184,-2.54,18.943>,<0,-1,0>,<74.183,-2.545,18.942>,USE THEO=YES
ENDMEAS/
LIN4 =FEAT/LINE,CARTESIAN,UNBOUNDED
THEO/<1.721,9.777,21.724>,<0,1,0>
ACTL/<1.722,9.779,21.724>,<0.0001059,1,-0.0000005>
MEAS/LINE,2,ZPLUS
HIT/BASIC,NORMAL,<1.721,9.777,20.18>,<-1,0,0>,<1.722,9.779,20.179>,USE THEO=YES
HIT/BASIC,NORMAL,<1.721,39.943,23.269>,<-1,0,0>,<1.725,39.946,23.269>,USE THEO=YES
ENDMEAS/
A2 =ALIGNMENT/START,RECALL:A1,LIST=YES
ALIGNMENT/LEVEL,ZPLUS,PLN2
ALIGNMENT/ROTATE,XPLUS,TO,LIN3,ABOUT,ZPLUS
ALIGNMENT/TRANS,YAXIS,LIN3
ALIGNMENT/TRANS,XAXIS,LIN4
ALIGNMENT/TRANS,ZAXIS,PLN2
ALIGNMENT/END