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Obtaining coordinates of points on surfac

kelveh

New member
Hi,


I am working on a project which involves cutting a mould (mold)using a 6 axis robotic arm with a router (cutting tool)attached to the end of it.


I have a cad model of what i want to cut, and from that, i need to extract some coordinates of some points on the surface of the model to input into the robot controller.


Is there a way, in Pro/E, to take coordinates of several points on a surface of the model?


I was thinking of making many cross sectional slices of the model, and for each slice, getting a series of points that are on the surface.


(It is a fairly large model and i am hoping that this process would be largely automated.)


Any ideas or suggestions?


Thanks in advance,
Kelvin.
 
yes you could use a datum plane and then intersect so that a curve is created on the surface you want to measure , then place points on the curve , then you could move the datum to different places.


I thought this could be grouped and then patterned by the dat dist but , i just checked and I 'm not getting it to included the datum and intersect even though I think I have before.... but I just woke up :)
 
I have tried patterning the intersect but it seems like the new intersects are the same shape as the original one.


I cannot pattern the points along the curve either. Is it possible to make the intersect curve into a sketch? Because patterning of points works along a sketch...
 
it's kind of odd as Iwas able to do this with one part fine , but not another


but basically offset a datum from from one of your existing main datums like you would if you were doing a x-sec


then make a datum curve using intersect , you should be able to place a point on the curve <ratio>and even pattern the point


then group it all together the dat,intersect curve and the point pattern then pattern the group using the offset value of the datum...


As to why it worked on one part and not the other ... wish I knew why


sorry kelveh, wish I could offer a easier method, or at least a why as to why it flys on one and not the other


Is this so you can check it on a cmm ? As this is a method I have used to do so before
 
Thanks for your help, i'll attempt that later.


This is the input for the cutting machine. the machine isn't a 5 axis milling machine or anything, and didn't come with a post processor or anything. it's not a cutting machine but a machine which can do a wide range of things depending on what tool is put at the end of it and how it's programmed.


Because it's going to cut a part, i'll need several hundred slices and several thousand points for each slice. I am just looking for an easy way to extract the coordinates of the points.
 
I don't envy the position your going to be in . Some points to digitize with a coordinate measuring machine ,cmm is one thing


but if you are want to surface a part not only are you going to need xyz points you are also going to need to know to retract and clear the part to get back to the next slice of points<section>.. not a 5axis but just for 3 axis surface milling


yeah file sizes get big real fast with a sculpted shape
 
oh yeah a major thing i left out , you need to make a surface offset the radius of your ball end mill for these numbers to work and the zero your tool to the center of the ball


and you have NO gouge checking so if there are any undercuts you need to work that areaout different way
 
hey wsylvester,


your pm inbox seems to be full.


hope you had a good christmas.


thanks so much for ur method, once i got it working, it's so simple.


i'm gonna attempt pro/E to do it auto with mapkeys :)


kelvin
 
Kelvin,


great, glad it's working for you.. and christmas was good ... not sure what to do with all the lumps of coal
smiley36.gif



thanks for the heads up on the inbox....deleted some of the old messages :)


wish i was down your way... cold as heck here


Happy New Year !!
 
Have youconsidered creating a hole table in Proe Draw to get the points from the model?


Use Tools / Hole Table / Create / Datum Points


Nowyou can select the table and save the table as a text file.


Highlite the table then use Table / Select Table


Now use Table / Save Table / As Textfile


Seasons Greetings to all
 
dbrainsky,


thanks for that tip, that's really cool. :)


now, if i couldjustfind a way of generating thousands of datum points in an automated way, it will be good :)
 
2008-01-04_045535_pt_pat_on_srf.prt.zip


I think the pattern problem is a bug associated with
Pro/E's geometry hierarchy (surf feature, quilt geometry,
curve feature, curve geometry, etc. ... maybe some subtle
difference in how we pick entities when we define ... ?)


If you can read the attached WF2 file and it shows what
you're seeing ...
 
wow that is very cool. thank you for that. i am guessing the 2curve:F14's are just the same curves? but needed to 'redefine' with?
 
I don't know for sure but think one listing is for the
feature and the other for the geometry; i.e. with selection
filter set to "Smart" if you pick the curve once you focus
on the curve feature, pick it a second time and it highlights
a different color and the focus is on the goemetry (which
may be a segment of a multi curve chain or feature). I'm
kinda fuzzy on all that stuff myself.
 
Rats.


I was just messing around with a point pattern and
'rediscovered' another problem / bug demonstrated by
the file I posted.


Note that the last pattern point is not coincident with the
end of the curve. That's because the increment described
"1 / 9" is rounded to .111 and used literally. The fix (if
it's still a problem in current versions) is to define the
increment in a Feature Relation; e.g. in the posted file ...
_ Tools / Relations / Look In: Feature
_ Select "Pattern 1" (f#15, fid_89)
_ Create the relations ...
p52 = 10
d51 = 1 / (p52 - 1) /*evaluates to .111111
_ And all should be well with that one.



An additional thought: I don't think I've seen the utility
iges_points.bat created and posted by Brian Adkins mentioned.
It'll extract the datum points from an IGES export and write
them to csv and ibl files.
 
Thanks for your help. it works well now. (well except that it starts to lag when i go over 5000 points :))
 

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