cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Community Tip - New to the community? Learn how to post a question and get help from PTC and industry experts! X

Unit Normal Vectors using a Field Point

JWayman
12-Amethyst

Unit Normal Vectors using a Field Point

Hello,
I have a colleague who is trying to extract the unit normal vector at a (large) number of discrete points on a surface.
Picture a basketball with a datum point at each intersection between seams (assuming basketballs still have seams, but you see what I mean). Then imagine a pin stuck in the ball, one at each datum point, sticking out normal to the surface of the ball. We want to know the X,Y,Z coordinates of each pin-head.
Pro/E will give us the unit normal vector at a point if we use Analysis/Geometry/Point, but only one point at a time.
I cannot help thinking, however, that we should be able to use something like a field point and a User-Defined Analysis to give us the values for all the points in one file.
Our problem is that, whilst we can get the Unit Normal Vector for any of our points, or we can get the full set of values of, say, cross-sectional area across the whole surface using a field point and an analysis feature. We cannot, however, work out a way to use the geometry analysis as the basis for the analysis feature.

Do you have any suggestions? Is there a nifty work-around? Am I barking up the wrong tree with field points & UDA?

I look forward to your constructive suggestions.

Regards,
John

John Wayman, C.Eng, FIED
Senior Mechanical Engineer

This thread is inactive and closed by the PTC Community Management Team. If you would like to provide a reply and re-open this thread, please notify the moderator and reference the thread. You may also use "Start a topic" button to ask a new question. Please be sure to include what version of the PTC product you are using so another community member knowledgeable about your version may be able to assist.
1 REPLY 1
davehaigh
12-Amethyst
(To:JWayman)

Many years ago I needed to list the locations of mirrors and the path length of the laser running through them. This was way before analysis features existed. I had a pro-program that prompted for some mirror locations in xyz and others in polar coordinate. To position the points in the model I use polar to xyz translation equations, and in the relations I also set parameters equal to the values. I had additional relations that calculated the path length and set parameters to that also.

In an assembly drawing of these laser beam paths, I created a repeat region that reported all the values I was interested in.

Sample relations
==============
Conversion from Spherical to Cartesian coordinates
X=rho*sin(theta)*cos(phi)
Y=rho*sin(theta)*sin(phi)
Z=rho*cos(theta)

Conversion from Cartesian to Spherical coordinates
Rho=sqrt(x^2+y^2+z^2)
Theta=atan(sqrt(x^2+y^2)/z)
Phi=atan(y/x)

Conversion of Rho to Cylindrical radius
R=rho*sin(theta)

David Haigh
Announcements
NEW Creo+ Topics: Real-time Collaboration


Top Tags