Retract distance problem

I just had Cad++ installed and I am having problems when I probe a hole and my probe retracts past the center of the hole and hits the back of the hole which inturn retracts and hits the front of the hole and goes into a loop of back and forth hits. I went to F10 then to motion and changed my prehit and retract distance but it did not help at all. Could a setting changed when Cad++ was installed? If so how do I fix it?

Parents

ADAM WALLACE over 11 years ago

Sorry, but that is not incorrect.

If his prehit is .250 and his hole diameter is .200, PC-DMIS won't try to ram the probe through the part to achieve the .250 prehit distance. It'll adjust the prehit distance to fit in the hole.

I asked if he was using Autocircle because adjusting his prehit distance won't make a difference if he is. If he is constructing circles using vector points, then his prehit distance will be a factor.

I just did some test with this prehit and retract and wanted to apoloigize because I was not completely right sorry thenev, this is what I found. It seems the prehit and retract if set larger then the center distance of the hole it will not prehit or retract any further then center. That being said if its a 1.0 hole and prehit/retract should work with what ever value you use that is shorter then the distance from the center of the hole. This is the little program I used to test this.

STARTUP    =ALIGNMENT/START,RECALL:,LIST=YES
            ALIGNMENT/END
            MODE/MANUAL
            FORMAT/TEXT,OPTIONS, ,HEADINGS,SYMBOLS, ;NOM,TOL,MEAS,DEV,OUTTOL, , 
            LOADPROBE/4X20X50MM
            TIP/T1A0B0, SHANKIJK=0, 0, 1, ANGLE=0
PLN1       =FEAT/PLANE,CARTESIAN,TRIANGLE
            THEO/<50.1912,84.1577,-45.3921>,<0.0001626,-0.0000477,1>
            ACTL/<50.1912,84.1577,-45.3921>,<0.0001626,-0.0000477,1>
            MEAS/PLANE,4
            HIT/BASIC,NORMAL,<47.6105,84.7484,-45.3916>,<0.0001607,-0.0000555,1>,<47.6105,84.7484,-45.3916>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.5594,84.9929,-45.3924>,<0.0001607,-0.0000555,1>,<52.5577,84.9922,-45.3924>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.5582,83.5442,-45.3925>,<0.0001607,-0.0000555,1>,<52.5582,83.5442,-45.3925>,USE THEO=YES
            HIT/BASIC,NORMAL,<48.0384,83.3461,-45.3917>,<0.0001607,-0.0000555,1>,<48.0384,83.3461,-45.3917>,USE THEO=YES
            ENDMEAS/
A1         =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
            ALIGNMENT/LEVEL,ZPLUS,PLN1
            ALIGNMENT/TRANS,ZAXIS,PLN1
            ALIGNMENT/END
LIN1       =FEAT/LINE,CARTESIAN,UNBOUNDED
            THEO/<48.0404,82.9992,-0.1396>,<0.9976965,0.0678354,0>
            ACTL/<48.0404,82.9992,-0.1396>,<0.9976965,0.0678354,0>
            MEAS/LINE,2,WORKPLANE
            HIT/BASIC,NORMAL,<48.0458,82.9993,-0.1402>,<0.0678354,-0.9976965,0>,<48.0404,82.9992,-0.1402>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.9927,83.3357,-0.1391>,<0.0678354,-0.9976965,0>,<52.9878,83.3355,-0.1391>,USE THEO=YES
            ENDMEAS/
A2         =ALIGNMENT/START,RECALL:A1,LIST=YES
            ALIGNMENT/ROTATE,XPLUS,TO,LIN1,ABOUT,ZPLUS
            ALIGNMENT/END
CIR1       =FEAT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<55.8649,80.5545,-0.1795>,<0,0,1>,0.6471
            ACTL/<55.8649,80.5545,-0.1795>,<0,0,1>,0.6471
            MEAS/CIRCLE,4,WORKPLANE
            HIT/BASIC,NORMAL,<55.8677,80.8779,-0.1796>,<-0.0151189,-0.9998857,0>,<55.8615,80.8781,-0.1796>,USE THEO=YES
            HIT/BASIC,NORMAL,<55.5422,80.5766,-0.1796>,<0.9977204,-0.067483,0>,<55.5422,80.5776,-0.1796>,USE THEO=YES
            HIT/BASIC,NORMAL,<55.8489,80.2313,-0.1795>,<0.0508264,0.9987075,0>,<55.8508,80.2312,-0.1795>,USE THEO=YES
            HIT/BASIC,NORMAL,<56.1882,80.5538,-0.1795>,<-0.9999639,0.0084963,0>,<56.1883,80.5607,-0.1795>,USE THEO=YES
            ENDMEAS/
A3         =ALIGNMENT/START,RECALL:A2,LIST=YES
            ALIGNMENT/TRANS,XAXIS,CIR1
            ALIGNMENT/TRANS,YAXIS,CIR1
            ALIGNMENT/END
            MODE/DCC
            MOVESPEED/ 70
            PREHIT/ 0.1
            RETRACT/ 0.1
CIR2       =FEAT/CONTACT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<0,0,0>,<0,0,1>,0.6471,0,360
            ACTL/<0.0003,-0.0006,0>,<0,0,1>,0.6473,0,360
            TARG/<0,0,0>,<0,0,1>
            ANGLE VEC=<0,-1,0>
            DIRECTION=CCW
            SHOW FEATURE PARAMETERS=YES
              REMEASURE=NO
              SURFACE=THICKNESS_NONE,0
              MEASURE MODE=NOMINALS
              RMEAS=NONE,NONE,NONE
              AUTO WRIST=NO
              CIRCULAR MOVES=YES
              CLEARPLANE=NO
              GRAPHICAL ANALYSIS=NO
              FEATURE LOCATOR=NO,NO,""
            SHOW CONTACT PARAMETERS=YES
              NUMHITS=4,DEPTH=0.2,PITCH=0
              SAMPLE HITS=0,SPACER=0.1
              AVOIDANCE MOVE=BOTH,DISTANCE=0.25
              FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO
            SHOW HITS=NO
            PREHIT/ 1
            RETRACT/ 1
CIR3       =FEAT/CONTACT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<0,0,0>,<0,0,1>,0.6471,0,360
            ACTL/<0.0002,-0.0006,0>,<0,0,1>,0.6475,0,360
            TARG/<0,0,0>,<0,0,1>
            ANGLE VEC=<0,-1,0>
            DIRECTION=CCW
            SHOW FEATURE PARAMETERS=YES
              REMEASURE=NO
              SURFACE=THICKNESS_NONE,0
              MEASURE MODE=NOMINALS
              RMEAS=NONE,NONE,NONE
              AUTO WRIST=NO
              CIRCULAR MOVES=YES
              CLEARPLANE=NO
              GRAPHICAL ANALYSIS=NO
              FEATURE LOCATOR=NO,NO,""
            SHOW CONTACT PARAMETERS=YES
              NUMHITS=4,DEPTH=0.2,PITCH=0
              SAMPLE HITS=0,SPACER=0.1
              AVOIDANCE MOVE=BOTH,DISTANCE=0.25
              FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO
            SHOW HITS=NO

cir3 did not prehit or retract passed center of the hole. Although the prehit/retract would adjust with a value smaller then center of the hole. Learned something new today thanks!!

Reply

ADAM WALLACE over 11 years ago

Sorry, but that is not incorrect.

If his prehit is .250 and his hole diameter is .200, PC-DMIS won't try to ram the probe through the part to achieve the .250 prehit distance. It'll adjust the prehit distance to fit in the hole.

I asked if he was using Autocircle because adjusting his prehit distance won't make a difference if he is. If he is constructing circles using vector points, then his prehit distance will be a factor.

STARTUP    =ALIGNMENT/START,RECALL:,LIST=YES
            ALIGNMENT/END
            MODE/MANUAL
            FORMAT/TEXT,OPTIONS, ,HEADINGS,SYMBOLS, ;NOM,TOL,MEAS,DEV,OUTTOL, , 
            LOADPROBE/4X20X50MM
            TIP/T1A0B0, SHANKIJK=0, 0, 1, ANGLE=0
PLN1       =FEAT/PLANE,CARTESIAN,TRIANGLE
            THEO/<50.1912,84.1577,-45.3921>,<0.0001626,-0.0000477,1>
            ACTL/<50.1912,84.1577,-45.3921>,<0.0001626,-0.0000477,1>
            MEAS/PLANE,4
            HIT/BASIC,NORMAL,<47.6105,84.7484,-45.3916>,<0.0001607,-0.0000555,1>,<47.6105,84.7484,-45.3916>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.5594,84.9929,-45.3924>,<0.0001607,-0.0000555,1>,<52.5577,84.9922,-45.3924>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.5582,83.5442,-45.3925>,<0.0001607,-0.0000555,1>,<52.5582,83.5442,-45.3925>,USE THEO=YES
            HIT/BASIC,NORMAL,<48.0384,83.3461,-45.3917>,<0.0001607,-0.0000555,1>,<48.0384,83.3461,-45.3917>,USE THEO=YES
            ENDMEAS/
A1         =ALIGNMENT/START,RECALL:STARTUP,LIST=YES
            ALIGNMENT/LEVEL,ZPLUS,PLN1
            ALIGNMENT/TRANS,ZAXIS,PLN1
            ALIGNMENT/END
LIN1       =FEAT/LINE,CARTESIAN,UNBOUNDED
            THEO/<48.0404,82.9992,-0.1396>,<0.9976965,0.0678354,0>
            ACTL/<48.0404,82.9992,-0.1396>,<0.9976965,0.0678354,0>
            MEAS/LINE,2,WORKPLANE
            HIT/BASIC,NORMAL,<48.0458,82.9993,-0.1402>,<0.0678354,-0.9976965,0>,<48.0404,82.9992,-0.1402>,USE THEO=YES
            HIT/BASIC,NORMAL,<52.9927,83.3357,-0.1391>,<0.0678354,-0.9976965,0>,<52.9878,83.3355,-0.1391>,USE THEO=YES
            ENDMEAS/
A2         =ALIGNMENT/START,RECALL:A1,LIST=YES
            ALIGNMENT/ROTATE,XPLUS,TO,LIN1,ABOUT,ZPLUS
            ALIGNMENT/END
CIR1       =FEAT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<55.8649,80.5545,-0.1795>,<0,0,1>,0.6471
            ACTL/<55.8649,80.5545,-0.1795>,<0,0,1>,0.6471
            MEAS/CIRCLE,4,WORKPLANE
            HIT/BASIC,NORMAL,<55.8677,80.8779,-0.1796>,<-0.0151189,-0.9998857,0>,<55.8615,80.8781,-0.1796>,USE THEO=YES
            HIT/BASIC,NORMAL,<55.5422,80.5766,-0.1796>,<0.9977204,-0.067483,0>,<55.5422,80.5776,-0.1796>,USE THEO=YES
            HIT/BASIC,NORMAL,<55.8489,80.2313,-0.1795>,<0.0508264,0.9987075,0>,<55.8508,80.2312,-0.1795>,USE THEO=YES
            HIT/BASIC,NORMAL,<56.1882,80.5538,-0.1795>,<-0.9999639,0.0084963,0>,<56.1883,80.5607,-0.1795>,USE THEO=YES
            ENDMEAS/
A3         =ALIGNMENT/START,RECALL:A2,LIST=YES
            ALIGNMENT/TRANS,XAXIS,CIR1
            ALIGNMENT/TRANS,YAXIS,CIR1
            ALIGNMENT/END
            MODE/DCC
            MOVESPEED/ 70
            PREHIT/ 0.1
            RETRACT/ 0.1
CIR2       =FEAT/CONTACT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<0,0,0>,<0,0,1>,0.6471,0,360
            ACTL/<0.0003,-0.0006,0>,<0,0,1>,0.6473,0,360
            TARG/<0,0,0>,<0,0,1>
            ANGLE VEC=<0,-1,0>
            DIRECTION=CCW
            SHOW FEATURE PARAMETERS=YES
              REMEASURE=NO
              SURFACE=THICKNESS_NONE,0
              MEASURE MODE=NOMINALS
              RMEAS=NONE,NONE,NONE
              AUTO WRIST=NO
              CIRCULAR MOVES=YES
              CLEARPLANE=NO
              GRAPHICAL ANALYSIS=NO
              FEATURE LOCATOR=NO,NO,""
            SHOW CONTACT PARAMETERS=YES
              NUMHITS=4,DEPTH=0.2,PITCH=0
              SAMPLE HITS=0,SPACER=0.1
              AVOIDANCE MOVE=BOTH,DISTANCE=0.25
              FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO
            SHOW HITS=NO
            PREHIT/ 1
            RETRACT/ 1
CIR3       =FEAT/CONTACT/CIRCLE,CARTESIAN,IN,LEAST_SQR
            THEO/<0,0,0>,<0,0,1>,0.6471,0,360
            ACTL/<0.0002,-0.0006,0>,<0,0,1>,0.6475,0,360
            TARG/<0,0,0>,<0,0,1>
            ANGLE VEC=<0,-1,0>
            DIRECTION=CCW
            SHOW FEATURE PARAMETERS=YES
              REMEASURE=NO
              SURFACE=THICKNESS_NONE,0
              MEASURE MODE=NOMINALS
              RMEAS=NONE,NONE,NONE
              AUTO WRIST=NO
              CIRCULAR MOVES=YES
              CLEARPLANE=NO
              GRAPHICAL ANALYSIS=NO
              FEATURE LOCATOR=NO,NO,""
            SHOW CONTACT PARAMETERS=YES
              NUMHITS=4,DEPTH=0.2,PITCH=0
              SAMPLE HITS=0,SPACER=0.1
              AVOIDANCE MOVE=BOTH,DISTANCE=0.25
              FIND HOLE=DISABLED,ONERROR=NO,READ POS=NO
            SHOW HITS=NO

cir3 did not prehit or retract passed center of the hole. Although the prehit/retract would adjust with a value smaller then center of the hole. Learned something new today thanks!!

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