Swept Blend with multiple trajectories?

[fphelps]

Hi everyone, I wanted to know if it was possible to do a swept blend with multiple trajectory lines? I am trying to do a ergonomic grip enclosure handle that will house a PCB board and a motor. I am wanting one end of the handle to be a triangular spline will sweeping to a circle at the other end. The reason for the multiple trajectories is the profile line of the "ergo" part where the hand would grip. Any ideas to help would be greatly appreciated. Thanks in advance.

This thread is inactive and closed by the PTC Community Management Team. If you would like to provide a reply and re-open this thread, please notify the moderator and reference the thread. You may also use "Start a topic" button to ask a new question. Please be sure to include what version of the PTC product you are using so another community member knowledgeable about your version may be able to assist.

[Patriot_1776 · Accepted solution]

Short answer: Yes. I prefer VSS's (Variable Section Sweeps). I think you have more control, and smoother results, but each has it's place.

[fphelps]

Thanks.

[fphelps]

Initially reading your response, I thought "Oh yeah I remember now" as it has been a few years since I used Creo. When I tried to perform this operation I didnt have too much luck. I'm wanting 4 profile trajectory / guide curves for my shapes to follow. 2 from the front view which would be the top and bottom splines. Also 2 from the top view which would be the side splines. When I try to do this I can only get 2 of the splines to select, and my shapes dont follow the splines like I thought they would. Is there any way you could provide a "quick and dirty" step by step. Thanks in advance for the help.

[fphelps]

I can sweep the spline across the 4 trajectory / guide curves no problem. Just FYI

[Patriot_1776]

The first selection is your "spine" trajectory, the others you select using "ctrl-select" to get the others. Your sections have to reference the "reference points" of the section (use query-select). Depending on the trajectories, and the section geometry, some VSS's WILL fail because the geometry simply does not work. Without actually seeing it, it's hard to tell.

[fphelps]

Sorry about that I was using wrong terminology. This is what I was doing initially with no problem. The only thing I am wanting to do differently is have a circle on one end doing a VSS to a square on the other end, or any object going to a different object via VSS actually. Thanks again.

[fphelps]

Variable section sweep with multiple sketches?

I read your post in this thread at the 3/28 1:28PM time spot. This is it, and will be my work around until I hear you can do things differently. Thanks for the help.

[Patriot_1776]

The limitation of the VSS is that you cannot have an arc segment turn into a line segment, or, worse, try and invert. When the radius goes to infinity, it divides by zero.... (a pun, meaning it fails).

[dschenken]

I'll wave the flag for the curvature-controlled element. There should be no problem because curvature only goes to infinity at a sharp corner, which is actually not realizable as even the sharpest corner is at least the size of an atom; not zero. Curvature can be a constant or varied along the element. The main constraint would be that the element be curvature continuous; no sudden changes/discontinuities in the curvature.

[Patriot_1776]

Sharpest ACTUAL, but geometry is assumed (yeah, I know....) to be perfect, and the software will try to make it so. Now, you could deliberately make it ALMOST go perfectly straight, just short of the end of your spine trajectory, and use a short boundary blend, but then why not use a BB in the first place? It would be SO nice if you could do that with a VSS......... Or, as I opined earlier, have a VSS with sectional control as well......

[fphelps]

How do you tell Creo, instead of sketching on the right side of the spline for the sweep starting point, that you want to start you sketch to be swept on the left side?

[fphelps]

Nevermind, just figured it out. By clicking the trajectory spline first, then click the pink arrow. Thanks.