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Sweep with relationship

daveyk_belgium

New member
Hello Boffins<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


I bet someone knows the exact answer to this one.


I need to model a sweep with a relationship. I have a composite curve, which is quite complicated, and I want to sweep a circle along it with the relationship r = k * sqrt(l - 235)


Obviously the circle will have a zero radius until 235mm, so I should not start the composite curve until 235mm from the start. From here, a circle with astarting radius of 0.05mm perhaps, and then the relationshipI can't get to work using trajpar.


Does the relationship need to be written in the sweep feature, i.e. sd=..., or as a part relationship, using the names of a couple of features (with trajpar_pnt)and a feature dimension d=....


Answers on a postcard please.


Many thanks


Dave
 

jeff4136

New member
Not sure if this is what you are after or not...

Create a truncated copy of the curve (trimmed at 235).

Create a Datum Evaluate Feature that measures the curve.

Create a part level parameter that reads the length.

Create a VSS and use a sketcher relation something like ...
sdX= .05+sqrt(trajpar*part_level_parameter)
... where sdX is the cirle diameter.

------------------

You should also be able to forget the trimmed curve copy and simply truncate the Origin during the VSS creation, I believe. (addendum: bad idea considering the offset)

Is there also a way to do this using a graph function?

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Edited by: jeff4136
 

jayuy

New member
daveyk,


I'm not sure if this is what you want to do.You can create a point using point on curve by length at 235mm, then split the curve using the point so can have a new curve trajectory for your sweep profile.
 

puppet

Moderator
u need to make a vss SWEEP FOR THAT TO WORK. A normal sweep will not.



equation being

r = 0.5 + trajpar*(k * sqrt(l - 235))





u could also drive it using a graph.







let me know how you go. if u still need help upload the file.







Edited by: puppet
 

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