3D spline

I'm trying to model a hose that curves through 3 dimensions. In the past, I have created a sweep, using the blue spline as the trajectory but this only produces flat (2 dimensional) curves. I created some points at varying X,Y and Z positions and through these points, I made a datum curve that was close enough to what I wanted. But the sweep won't recognize the datum curve as a trajectory. Can someone help me with this or point me to a tutorial on how to do this? Thanks. Peter

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Peter
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I forgot to say that I am using WF2.

Peter wrote:

Reply to
Peter

The Sweep feature won't follow a spline. You could do it with straight sections, single or multiple radiuses. If all you really need is to make a circle follow the spline, use 'Insert>Advanced>Pipe'. You can specify solid or hollow, OD and wall thickness. It kinda looks like a hose.

David Janes

Reply to
David Janes

You cannot sweep along a spline. Choose the best two views that describe the path and draw curves on planes, make sure that the ends are coincident and that the curves do not self intersect. Create a curve by intersecting these two and you'll be able to sweep along it. If your run is complicated you may have to make it in several parts.

Reply to
kenny

Can't try this on WF2 as I'm on WF3 but...

Some thoughts;

Are you using Insert > Sweep? I think using VSS will allow you to use curve thru points. [I'm led to believe this should be the default function now for a constant section sweep - unless you have nontangent chain or want to use the fill option]

Have you got ISDX? A 'free' Style curve through your points should also be recognised

Create a surface using the curve as a boundary and then use the surface edge as your traj?

WF3 will use a curve thru points as a traj on a insert > sweep

Sean

Reply to
Sean Kerslake

Whilst you can't sweep along a spline, (splines don't have orientation) you can create a multi-trajectory sweep along 2 splines, so if you create a second spline parallel to the first, you can make the feature as you describe it.

Hence, whilst 'pipe' will effectively make a rond section sweep along a spline, if you want other shapes you'll then need to extrude a surface through the pipe centreline, and use it's intersection with the pipe as your second trajectory.

kenny wrote:

Reply to
John Wade

Good question, Peter; lot's of good ideas guys. One of the suggestions, the VSS still puzzles me. It's not that it's not possible. It just seemed, when I first thought about it, that there's no good way to create the second trajectory curve so that it controls the section size and shape as intended and without kinking or selfintersecting. And we are talking about a 3d curve that can wiggle all over the place, changing directions repeatedly, even doubling back on itself. So a simple copy/offset wouldn't do. Any ideas? If you can do it, I'd like to see it.

David Janes

Reply to
David Janes

Hi David, You can make the second curve, but the only way I know is to create a pipe along the initial spline (which technically you aren't doing, but if you put it through the same points with the same constraints the centreline should be the same ) then extruding a surface through the pipe, with the centre spline as sketch, intersecting the pipe surfaces and the extruded surfaces to get a second curve offset from the first by the radius of the pipe, cutting out the pipe, and using the two trajectories left.

I have only done this once, looked at the resulting model, thought 'what a mess, my intended section is more or less perpendicular to a plane anyway, I'll let that drive the direction and accept the model isn't perfect'

Reply to
John Wade

Maybe I've missed something in the discussion but you don't have to have two trajectory in the VSS function, surely Peter only wants one traj?

Theres also an Option on the Dashboard - Constant Section Sweep

Sean

Reply to
Sean Kerslake

Additionally, unless there's something driving d(radius) it remains constant. (The Constant Section option is interesting, allows the use of additional trajectories that create conflicting or unsolvable constraint(?) and allows the use of projected section curves.)

- - - - -

Wondering about the difference in users' perceptions re sweep functions; is VSS relatively new to Foundation? Perhaps it's because I'm a newcomer to Pro/E (started with WF), but seems to me that VSS is the 'one size fits all' sweep function, the rest (older?) serve occasional or 'special purpose' needs. I've gotten the impression from some older users that they think VSS is "over kill", etc. and it's puzzled me.

================================

Reply to
Jeff Howard

I guess, Sean, that you know a good bit more about the VSS in WF2 than I do. Thanks for the tip. And, yeah, works very cool. Well... oh, no, not in WF2 (or at least I can't confirm). I did it in the only thing I have available for messin' around ~ the SE of WF3. So, it works great there.

Come to think about it, this doesn't accomplish anything beyond the Pipe feature, if one wishes to do only a round hose. You can, with the new VSS, create any shape to sweep and with only the central 'trajectory'. Well, I guess I exaggerated: an elipse follows the normals and constraints based on the twists in the 'curve thru points' foundation of the section. IOW, Pro/e picks the sketch plane and orientation and your elipse WILL follow the vertical/horizontal orientation. Or maybe this is where that second trajectory comes in, where you want to get beyond the limitations of this default orientation. And, Sean, you didn't just do an artful dance around how to construct this second 3d section guide trajectory by bringing up the single trajectory VSS, did you!?! I'd like to be able to tell that second trajectory to twist, but stay equidistant from origin or to stay in a normal plane but increase in distance, meaning the section expands. I don't know how to do any of these with the resources available.

David Janes

Reply to
David Janes

Part of VSS' beauty is that you don't need the second trajectory. (Or if you need one for another function, create it with VSS.)

Place an angular dimension relative x or y reference. Drive the angle as a function of trajpar.

Drive the dimension as a function of trajpar.

I think VSS tends to intimidate, sometimes, because if you don't understand how it drives section constraints it will be frustrating. Once the lamp starts to flicker, though, it becomes apparent it's an incredibly versatile function.

Reply to
Jeff Howard

Dammit, so there is. I'll be using that then. That's what comes of sleeping in training courses.

Reply to
John Wade

There is a way to do this with only one trajectory. Set up a ribbon on this with as many controls as desired to control the X-traj.

Reply to
kenny

You get training classes!?! I thought it was just a myth.

Reply to
David Janes

I did at Caterpillar, but nowhere else.

Reply to
John Wade

What you have done is fine - I did this the other day and had the same problem. You create a 3d spine as you have done by creating points then creating a spline through these points. You can also set the tangency/normal at each end to control it a bit more. Then choose VARIABLE SECTION SWEEP. Just use the spline you created as a single trajectory, sketch your profile in the sketcher that appears and away you go!

Worked for me :)

Reply to
skyap

Yeah, sounds familiar. They, as the biggest users of Pro/e on the planet, had some respect for it and for what it took to be a proficient user. I was there as a contractor, the direct hires got the training. At least they went through a tooling apprenticeship program to learn stuff about how a product gets made. That was the best thing about Cat. At least I had the tooling apprenticeship and the formal training on Pro/e before I got there.

Reply to
David Janes

It looks like the question that I asked about 3D hose created quite a response and although most answers were waaay above my skill level, I thank everyone who replied. I was getting kinda frustrated and later on in the evening, while watching Millionaire, I happened to mention it to the wife (the problem not the frustration). She said that I should create the points with the "Offset coordinate system point tool" option from the datum points flyout, then I can make a datum curve through the points and use the curve to create a hose. (Where does she pick this stuff up from?) "Yea right!" I snorted (trying to save face), "sweep won't recognize a datum curve". She never even raised her eyes from her knitting but smiled and said quietly "Try Variable section sweep". (she must get it from one of these Home improvement shows that she is always watching). I almost dropped my Guinness. "Could this be possible?" I thought. I pushed aside my bag of Ripples and sweeping the crumbs from my shirt front, I rushed to check it out. And guess what? It worked, exactly as I wanted. Of course, I never told her that, but she knew. The most difficult part is determining the XYZ positions for the points, but after she explained how to get them, it became much more semi clear.

Thanks again to all who replied. Peter

Peter wrote:

Reply to
Peter

That was a hint, wasn't it?

Reply to
neonerd

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