Measuring Point Profile from THEO and ACTL Values

Hello! First of all, I would like to mark that I am not experienced in operating CMM.

I wanted to check the coordinates of our measurement and thus required a detailed log of the process from the operator. I am assuming that THEO and ACTL values are theoretical and actual coordinates of the points. Also checked if my assumption is true on Nexus Hexagon docs.

Anyways, I started to calculate the distances between the THEO and ACTL coordinates. Then compared to the ones given as profiles on the report.

PNT11 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524,21.406,-5.05>,<0.2517976,0.1223556,-0.9600141>
ACTL/<-4.529,21.41,-5.036>,<0.2517976,0.1223556,-0.9600141>
TARG/<-4.524,21.406,-5.05>,<0.2517976,0.1223556,-0.9600141>
SNAP=NO
SHOW FEATURE PARAMETERS=YES
SURFACE=THICKNESS_NONE,0
MEASURE MODE=NOMINALS
RMEAS=NONE,NONE,NONE
AUTO WRIST=NO
GRAPHICAL ANALYSIS=NO
FEATURE LOCATOR=NO,NO,""
SHOW CONTACT PARAMETERS=YES
AVOIDANCE MOVE=BOTH,DISTANCE=0
SHOW HITS=NO
MOVE/CLEARPLANE

According to this calculation, i thought that my measurement should be off by 0.015 mm. However, as you can see below, the result was 0.019 mm off.

So, at this point i am curious how deviation is calculated by PC-DMIS. Can anyone care to explain?

Thanks in advance!

Parents

UgurEmanetoglu1 11 months ago

On first post I forgot to add what puzzled me.

PNT11 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 21.406, -5.05>,<0.2517976,0.1223556,-0.9600141>
ACTL/<-4.529, 21.41, -5.036>,<0.2517976,0.1223556,-0.9600141>
TARG/<-4.524,21.406,-5.05>,<0.2517976,0.1223556,-0.9600141>
SNAP=NO
SHOW FEATURE PARAMETERS=YES
SURFACE=THICKNESS_NONE,0
MEASURE MODE=NOMINALS
RMEAS=NONE,NONE,NONE
AUTO WRIST=NO
GRAPHICAL ANALYSIS=NO
FEATURE LOCATOR=NO,NO,""
SHOW CONTACT PARAMETERS=YES
AVOIDANCE MOVE=BOTH,DISTANCE=0
SHOW HITS=NO
MOVE/CLEARPLANE

PNT12 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 18.708, -11.565>,<0.2517963,0.7653502,0.5923156>
ACTL/<-4.535, 18.679, -11.582>,<0.2517963,0.7653502,0.5923156>
TARG/<-4.524,18.708,-11.565>,<0.2517963,0.7653502,0.5923156>
SNAP=NO
SHOW FEATURE PARAMETERS=YES
SURFACE=THICKNESS_NONE,0
MEASURE MODE=NOMINALS
RMEAS=NONE,NONE,NONE
AUTO WRIST=NO
GRAPHICAL ANALYSIS=NO
FEATURE LOCATOR=NO,NO,""
SHOW CONTACT PARAMETERS=YES
AVOIDANCE MOVE=BOTH,DISTANCE=0
SHOW HITS=NO
MOVE/CLEARPLANE

Now, when i do the same calculation for distance between PNT11 to PNT12;

I get the exact measurement obtained from the report.
Cancel
Vote Up 0 Vote Down

Sign in to reply

Cancel

WilliamL 11 months ago in reply to UgurEmanetoglu1

I'm not sure if you meant to do this, but your calculator data input looks wrong if you're using the actuals.

X1 = -4.535, Y1= 18.679, Z1= -11.582

X2= -4.524, Y2 = 21.41, Z2= -5.036

Your X2 should be 4.529

PNT11 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 21.406, -5.05>,<0.2517976,0.1223556,-0.9600141>
ACTL/<-4.529, 21.41, -5.036>,<0.2517976,0.1223556,-0.9600141>
TARG/<-4.524,21.406,-5.05>,<0.2517976,0.1223556,-0.9600141>

PNT12 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 18.708, -11.565>,<0.2517963,0.7653502,0.5923156>
ACTL/<-4.535, 18.679, -11.582>,<0.2517963,0.7653502,0.5923156>
TARG/<-4.524,18.708,-11.565>,<0.2517963,0.7653502,0.5923156>

Not that it matters much, your math came out to be the same

Reply

WilliamL 11 months ago in reply to UgurEmanetoglu1

PNT11 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 21.406, -5.05>,<0.2517976,0.1223556,-0.9600141>
ACTL/<-4.529, 21.41, -5.036>,<0.2517976,0.1223556,-0.9600141>
TARG/<-4.524,21.406,-5.05>,<0.2517976,0.1223556,-0.9600141>

PNT12 =FEAT/CONTACT/VECTOR POINT/DEFAULT,CARTESIAN
THEO/<-4.524, 18.708, -11.565>,<0.2517963,0.7653502,0.5923156>
ACTL/<-4.535, 18.679, -11.582>,<0.2517963,0.7653502,0.5923156>
TARG/<-4.524,18.708,-11.565>,<0.2517963,0.7653502,0.5923156>

Not that it matters much, your math came out to be the same

Children

No Data