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variable x section diameter


here is the problem

imagine a 600ml coke bottle. with out all the ribbing but the basic outline of it, sitting on a table.

now at different hights from the table i want to make a x-section and find its diameter. and then use this diameter to drive some external features. reason being that bottle shape will change frequently so i wish to only update the bottle and have all external components dirived from that.

i tried to do it with a analysis feature to tell me datam curve radius at that x-section but when the x-section moves up and down. it gives me a computational error where i have to respecify the datam curve.

anyone have any ideas of a better way to approach the problem?




Active member

Can you attach the file so that I could help you? I have different solutions , in my mind, for this problem but first I want to know what exactly you want.



hey solved this one myself

1)i draw up the bottle. and then offset afew datum planes going up the bottle.

2)then create a datum curve through the bottle at the point of each curve

3) create a field point each the datum curves

4) create a analysis feature measuring the distance from the field point to the centeral axis of the bottle ( giving radius @ a relative hight)

5) use the analysis feature in the assembly model the drive the other componentes with the diameter of the given heights.

so now all i do is copy the entire assembly drawing to another directory. and modify the design of the bottle. then update the assembly few times and presto :p

idealy it would be great if i could just be given a model of a bottle and then copy over my datam planes, points, curves and anaylsis features to every given model.

would that then be a skeleton model?


Using say 4 datum curves to define the shape of the bottle exterior and then use 1 vertical curve down the center of the neck. Use the vertical central curve as the trjectory and 4 other curves as the curves for the cross section to stick to.

Create a single field point on the central curve. Create a plane through the point parrallel to the base. Create a point in the plane using the plane and one of the four curves (crvxsrf) Group these together and make a User DEfined Analysis feature. This will give you all the info you need. If you also create a surface with a circular curve then you can also get cross sectional area of the bottle at every point. Use one sided volumes to find the FIll Level at any pont. This is a common problem in the container industry.

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