Software Review: Solid Edge ST, Part 221 Jan, 2009 By: Jeffrey Rowe
A number of new capabilities set Solid Edge ST apart from its competition.
In the previous MCAD Tech News, I discussed Siemens PLM Software's new Solid Edge ST and its Synchronous Technology (ST) feature. This time I'll examine the new user interface and a few more of the software's many new capabilities.
The UI is actually the crux of ST, so I'll start there. The new user interface for Solid Edge ST is relatively clean, has a definite look and feel of Microsoft Office 2007, and becomes intuitive in short order. A good UI always eases the pain of the learning curve, and I think most users will see the benefits. I have to mention that I consider a software application's documentation (online help, tutorials, etc.) a part of the UI, and although Solid Edge ST's material is better than previous versions, it is still fairly feature-oriented as opposed to being task-oriented, which I believe would have provided a better level of assistance and lower levels of frustration, especially for new users.
For new users coming over from AutoCAD, Solid Edge ST contains unified 2D and 3D commands that should make the transition a bit easier. You also have the ability to turn 2D regions into 3D geometry — not totally unique, but a nice implementation in Solid Edge ST.
The Steering Wheel
The Steering Wheel is the primary direct editing tool that is at the heart of ST for modifying models by moving and rotating 2D and 3D geometry. It automatically displays whenever you click on a face. The Steering Wheel comprises parts that reposition its location or orientation, as well as perform synchronous move and synchronous rotate operations along its primary and secondary axes. It's really a geometric editing handle for aligning to any geometric element to achieve precise results. It does take a bit of practice to reorient the Steering Wheel, but doesn't take long to get the hang of it. The Steering Wheel can do a lot of things, though, so I'd recommend spending the time to get comfortable with it.
The Steering Wheel, Live Rules, and Pathfinder are the fundamental tools for using and optimizing ST in Solid Edge ST. Click image for a larger view.
Live rules are what determine the behavior of the Steering Wheel. In other words, Live Rules determine the faces that will be affected by a move or rotate operation with the Steering Wheel, and the Steering Wheel determines the degree and direction of these operations. The Live Rules feature automatically finds and maintains geometric conditions during drag or dimensional edits. For example, things like tangency, symmetry, and concentricity are automatically found and maintained, even in models that did not originate in Solid Edge or NX. You can suspend Live Rules at any time, and assemblies are independent of Live Rules.
At times I also found the Live Rules window distracting when I wanted to focus on the model, but it can be minimized and out of sight. Also, the Live Rules are not always as intuitive as they could be in the way that Solid Edge applies and follows those rules. This situation could cause problems because it can lead to unintended results, but I found that it generally worked well for locating and displaying inferred geometric relationships between faces. I would like to see Live Rules become more predictive with the ability to "learn" and apply more automatically in the future.
Dimension behavior in Solid Edge ST is something you should take time to understand because it will let you design with 3D driving (locked) and driven (unlocked) dimensions. This is a key aspect of ST; you can dimensionally or parametrically drive part shapes and sizes, but without the overhead of a history tree. Driving, locked dimension values are red, and they control the size, orientation, and location of an element. Their value is not changed when a connected face is resized or moved. Driven, unlocked dimension values are blue and dependent on the value of other dimensions or elements. The unlocked value is controlled by the element it refers to, or by a user-defined formula or variable. When faces connected to a dimensioned edge are modified, the unlocked dimension value changes. You can add 3D driving dimensions to imported models, and you can also add and change 3D driving dimensions and 3D constraints anywhere at any time.
In part mode, the Pathfinder is a collection of sketches, features, and relationships used for creating the part. In an assembly, the Pathfinder is helpful for working with component parts. The Pathfinder can be used to activate specific parts so you can edit them while the entire assembly is still displayed. You can also use the Pathfinder to view, modify, and delete assembly relationships for positioning the parts, reordering parts in the assembly, and even helping diagnose various fit and position problems within an assembly.
Using synchronous modeling techniques, changes to a model, even late in the design process, are relatively easy to accomplish, as seen above and below.
Some Other Commands and Operations
I found the Relate command to be one of the more useful ones in Solid Edge ST. It modifies the position and orientation of selected faces so they are geometrically related to a target face on a part with options you choose, such as making two faces parallel or dimensions equal. You can also define or assign a relationship that persists and is maintained if the model is modified. You can delete a persisted relationship with either the Pathfinder or Advanced Live Rules.
Product manufacturing information (PMI) has a place in Solid Edge ST and consists of dimensions and annotations that are added to 3D models and is used for design review, manufacturing, and inspection processes. The same 3D dimensions you placed to modify your model during the design process can also serve as PMI for manufacturing. You can add more or change existing dimensions as necessary to convey manufacturing intent, and these can be retrieved onto the drawing, as well.
Depending on what your needs and preferences are, there are several methods for modifying synchronous models that include moving or rotating model geometry with the Steering Wheel; editing model dimensions; defining 3D geometric relationships between faces; detaching and attaching faces; and modifying individual features that are part of a feature set. I found the most efficient ways to modify a model were directly editing dimensions followed closely by using the Steering Wheel.
So, while Solid Edge ST certainly does have a lot of competition from vendors that do and do not have direct model editing and a history-free approach, it also has a number of capabilities that differentiate it, making it an MCAD application that deserves more recognition and consideration than it may have in the past.
I've spent quite a bit of time with Solid Edge ST and have only scratched the surface with what's new in it this time around. If you have any specific questions about its functionality, please feel free to contact me.