How to create Locus for Connecting rod? UG Nx7.5

[nithink]

Is there any way to genertae automatic locus for connrcting rod when Crankshaft rotated.
Need a asociative profile because con rod dimensions need to vary for different bore..

Nx 7.5.5.4

Teamcenter 8

 

[JohnRBaker]

Could you provide more details as to exactly what you're looking for?

I looked for some references with respect to 'locus' and crankshaft/connecting rod motion, and found this item:

[URL unfurl="true"]http://homepages.udayton.edu/~rhardie1/ECE203/Piston%20Locus%20Design%20Problem.htm[/url]

As well as the attachment below:

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[nithink]

@ John,same thing i am talking about.

Found couple of options.

One in Assembly sequencing where we have option for Motion enevlope after creating a sequence.It will create a light weight body [shaded]

One more is using Motion simulation and trace the path - issue here is either we have to go by a solid body trace that takes bit time and create lot of solid body or we can go to a curve selection which wont give a single path

but neither of this gives what i need,as this makes going out of UG modeling,thats to create a envelope when crankshaft moved.We need this envelope so that to decide clearence fro crank case.

components affect the clearence envelopes are Cranckshaft counterweight and Conr rod big ends.

the reason i need this in Modeling is because we have to try different configurations ..so it will be easier to get clearence envelope

Nx 7.5.5.4

Teamcenter 8

 

[nithink]

Anyway thanks again John for the PDF

Nx 7.5.5.4

Teamcenter 8

 

[JohnRBaker]

Not sure what you mean by "out of UG modeling"? If you're referring to the fact that the envelope is a faceted body, you can still perform clearance analysis and take measurements using the faceted body and the rest of your model. Also, you don't have to create the envelope using all the components. You can just select any ONE in the assembly even if many parts are moving.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[nithink]

John,envelope depends on con rod and counterweight of crankshaft [con rod have some extra protrusion in big end].

what i thought was instead of simulation tools whether we can create some curves or sketches in modeling itself.

Nx 7.5.5.4

Teamcenter 8

 

[JohnRBaker]

While I have no direct experience using these tools, if you're using the Motion Simulation module you can add what's called 'Markers' on the various moving parts of your assembly and then by using the 'Trace' command you can select any one of these 'Markers' to create a 'trace' of the path of the 'Marker' as the kinematic motion of various parts of the Assembly are computed using the Motion Simulation solver.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[moog2]

FYI,
I looked at Johns link to the "homepages.htm"
In the description it states that the piston motion is symetrical, but it should be noted that, in some engines the gudgeon pin is not located in the centre of the piston, but instead may be slightly in from or behind centre. This affects how the engine makes its power, and also makes this motion NOT symetrical.