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how to design a 3D cam profile in nx 1

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Santhosh_94

Mechanical
Dec 16, 2014
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Does anyone know how to model a cam profile using given data's as polarcoordinates of roller follower centre, roller radius, minimum radius of cam in nx???
 
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I'm sure someone somewhere has probably written an NX Open program to do something like that.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
Perhaps someone would like to volunteer one or else you might have to either write it yourslef, or hire someone to do it for you. There are people and organizations out there who offer these sorts of services.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
I would call for help from Catia in this case
1. I would make it all in AutoCAD, and save file as *.dwg
2. open drawing in Catia 5.xx (just click on file-open-select dwg,...)
3. select the profile in the drawing, COPY
4. go to the part file in Catia
5. insert a sketch in that part file
6. whele in sketch : PASTE
7. OVER
8. save as a step file and open in it in UG.

OR make it in Catia 5.xx, export as a stp file and open it in UG.
Sometimes we have to use multiple programs. There is no program doint it all at the fast speed.
If no Catia license use Solid Works or,...
 
Exactly what is it that you think you could model in AutoCAD and then transfer to Catia (or SolidWorks) and eventually to NX that you COULDN'T model in NX in the first place?

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
This is dizzy for me, what is that you cannot do ?
The polar coordinates ?
Do you want to automate the process ?

( neither do i understand what Nikon speaks about, but I don't think that post was serious.)

Regards,
Tomas
 
Hello,

use the attached excel file to convert the polar into Cartesian coordinates.
Then export data from excel into a text file and change the extension into *.dat file and import into NX using File-->Import-->Points from File.

With this points you can create a spline using the Fit curve command.

best regards

kscnoname


Unigraphics Key user

V13, V14, V15, V16, V17, V18, NX, NX2, NX3, NX4, NX5, NX6, NX7.5, NX8, NX8.5, NX9
 
 http://files.engineering.com/getfile.aspx?folder=fd0aad9f-0ac8-4476-936e-c8881cdc8619&file=polar-rect_convert.xls
Exactly @kscnoname

I tried this method once and unfortunately got the cam profile to be wrong.
Thing to be noted Roller's center polar coordinates are only known not the point where the cam gets in contact with the roller if so i could use this method and this might work.
Actually i used this by converting my coordinates by subtracting the roller radius to get the contact point but only for dwell regions it works and for a rise and falls to get the tangential contact, my method of subtracting the roller radius fails.

As for non practical method is concerned
Points of roller center's are been imported from an excel file as the above mentioned method
now roller circles are been drawn on one point and then it can be patterned to all other points(Say for example if we have coordinates for each angle we get 360 circles this too increases if the angles are incremented by 0.5 degree)
now tangential line is drawn from one roller to other separately
similarly for one roller to other and from that one to the next one the process is continued
finally the profile may be completed
as of dwell portions is concerned there wont be any problem since we could use an arc

The problem is using this much operation in the sketch the system is not able to take up the load and slows down and my time to model it gets increased so practically its not possible.

Searching for a way which is easier than this
Thanks for people who have responded till now :)

 
The method you've described is what I would do if I was confronted with this problem, as long as it wasn't something that I needed to do weekly or something. In that case, I would have written for me an application which would have basically automated that process, but internally the process would have been basically the same, just automated so as to avoid the drudge work.

BTW, the method you described above is basically what you'd find if you were to look at the 'Cam Design' section of the 'Machinery's Handbook'.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
Note that if the profile of the cam is limited to only arcs and line segements. that will certainly simplify things and while NX may not have an explicit 'Cam Design' tool, if you're willing to live with those limitations, it wouldn't be that difficult to create the profile using the NX sketcher.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
I was just looking at a function which we had hoped to have sooner but now looks like we won't be getting it until next year, that it would make the creation of a cam profiles about as easy as possible, and it would NOT be limited to only arc and line segments for the profile. And while it's not an explicit cam profile creation tool, all I would need is the centerline path of the follower and the diameter of the cam roller and I would have a result in only a couple of keystrokes, with a typical output looking like this:

CamProflieusingSewptSolid_zps584c17db-1.png


John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
Did you try importing points?
Insert > Spline> through points > points from file.
you need to put all the co ordinates in a notepad and then change its extension to .dat

 
John just keeps on teasing us. I am really looking forward to this new feature. In I-Deas we was able to constrain geometry in an assembly. Then we was able to track a point as the geometry changed and it would create a spline through which this point traveled. I know we do not have this funtion in NX. I do not know if this is in the motion simulation or not.
 
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