DEVELOP3D - Technology for the product lifecycle

Today is the launch of the latest release in Siemens PLM Software’s NX product line and I’m sure the online world will be aflutter with all manner of content and thoughts on what the company is up to with its flagship product. I wanted to do things slightly different and take a look at a different areas of the release over the course of a couple of posts and spend some time focussing on the details of what’s changed and what looks exciting. And today’s subject is, Synchronous Technology.

While the launch saw a huge amount of noise made around how this breakthrough technology was impacting Solid Edge, many missed the really joucy stuff, the place where Synchronous Technology made much more sense in terms of supporting and adding to existing workflows and capabilities - and that was within NX. The problem was that NX has, for many years, allowed the user much more freedom from the traditional Feature/History way of working found in Solid Edge and its mainstream competition. The removal of a reliance on history was something that didn’t make huge deadlines purely because that’s how NX has always worked to a greater or lesser extent. Also, the manner in which it was integrated into NX was much less prescriptive than Edge and allows the user to much greater choice. History (of each modelling operation executed) could be stored if needs be, or you could simply work in the way you wanted without storing that trail of operations. But which ever way the user chose to work (and experience tells me that users use the most appropriate method based on the task at hand), the one thing that Syncronous Technology couldn’t do was work with non-prismatic geometry. Basically, while the drag and drop, auto-inferred, relationship driven way of working that Sync Tech brings, didn’t give you much advantage once you stepped outside of extrudes, revolves, shells, fillets and chamfers.

For NX 7.5, this changes. And changes big style. The concepts of Sync Tech have now been integrated into NX’s pre-existing tools for working with typically surface-based complex geometry in the form of iForm operation. Like the xForm tools that have been around since the system was called Unigraphics, it allows you to manipulate surfaces on a very fundamental level. You can dive in and manipulate the geometry using a range of methods which it would take quite sometime to explain with words. So, instead, we’ve got a little time lapsed video to show how it works. Have a watch of this, then pop back for some thoughts.

Cue the VT

What you just saw is a couple of things. Firstly, you can see that you can dive in and use the iForm modelling to work with the surface geometry very easily. You can edges, points or isoparms and directly manipulate the geometry to the shape you want. Previews are all fully details and give you a clear indicate of what you’re doing (and of course, if things are not going to work) and the whole process is highly interactive. For those existing NX users out there, the question of how these tools different from the existing xForm tools is a valid one. The basics are this:

xForm uses a cage-based edit methodology for surface geometry. That cage isn’t necessarily ‘attached’ to the surface but rather is used as a guide to help manipulate the form into the shape you require. As below - you can see that the control handles are separate but linked to the geometry.

iForm differs in that its using geometry handles that are an integral part of the surface geometry such as control points or vertices or isoparms to manipulate the form. See below for an example.

Both are used in this video to great effect (keep an eye on the dialog, it’ll tell you which is which).

In reality, the two approaches are quite subtly different but in use and end goal, very similar, but the real power comes when you look at both easy it is to manipulate the geometry in the first place, and the addition of the Sync Tech-based intelligence that’s now available. Within that video, you’ll see that much is inferred from the model. Symmetry is used to great effect (where the flash mount is manipulated for example at 0.22 seconds in),

The other thing to notice is that the modelling operations are all conducted without worrying about the history. One key section to watch starts at 1:32. In other systems, editing the front face of the camera. in a traditional history-based modelling system, to make this edit would require a roll back to when that face was created, a heavy edit and a recalculation. In a surface-based system, it would require pretty extensive rework. What you see here is that the face is grabbed, edited using the xForm tool to change it from being a planar face to a more sculpted form - which is all very possible. What’s you need to note is that the fillets are not only maintained, but update live as the geometry is changed. That, my modelling fiend friends, is something quite special. You can see it again and again in this video.

Another key example of how this works and works well is found later when the curvature of the top of the battery housing/grab handle is matched to the top surface of the flash housing - using the Replace Face operation (which was introduced in NX 7). Again, creating that type of feature on the fly would be difficult. Again, you’d need to ensure that your surface could be extended to create a clean surface (which is often done by overbuilding surfaces where they ‘might’ be needed), but still, creating that form after the fact would be difficult in other systems - particularly if you wanted to incorporate some form of offset, as is done here.

History Schimistory

What you can’t see here is that a history is maintained. Maintained is the word to focus on. The operations you see don’t rely on the history as their recipe for creation, rather, its used as reference. Everything ‘could’ be stored if needs be, but when you’re experimenting with form, as is shown here, the list of every edit could become quite unwieldy - although it wouldn’t effect performance as the model wouldn’t be reliant on it. The point is that you have the option. Again, that’s something quite quite powerful and actually delivers on the promise of synchronous Technology - in that it frees you from many of the constraints that are inherent in history-based modelling system - yet it does so in an environment in which the benefits of that history-based approach can be used - and used where and when you need them. Perhaps that’s a good point to finish on.

A final thought

There’s been huge discussion over the history vs non-history approaches. There are vendors on each side, usually split with the toolset they offer (if you have a non-history-based system, then you’re for that approach, naturally). What the NX 7.5 release shows is that the combination of the two approaches, rather than splitting them out and wondering which path to take, a more intelligent approach would be to allow the user to use both, on an adhoc basis, and get the job done instead of following a single path and struggling with the inherent weaknesses of both. After all, these are tools for design. Surely it’s better to have a tool that allows you to create the geometry you want, edit it in the manner you want, without worrying about the underlying technology, is really what designers and engineer’s need.

Next up we’re going to take a look at the advances NX 7.5 has made in the area of High Definition 3D or to give it it’s shorter, snappier name, HD3D. Be back at you soon.