There are two primary methods of building a 3D CAD model. 

A history-based solid model is built from a number of separate features. Each feature is defined in sequence, often as a 2D profile that is then extruded, revolved or swept into a solid feature. The new feature is then combined with the existing model by using add, subtract, or intersect operations as appropriate. The process is then repeated, building up the finished part in a sequential step-by-step process.

History-free models lose their underlying definitions, but the advantage is that individual faces can be edited independently.

Siemens PLM Software (www.solidedge.com) effectively resolves the debate with its Solid Edge software, which is based on its Synchronous Technology (ST). Models are built using history-based methods but can be edited using history-free techniques. 

Better yet, history-based types of relationships can be added to history-free models. This is particularly useful when you receive a 3D solid model that was exported from a different CAD program. Such exported models are typically “dumb,” and have had their underlying definitions stripped out. Solid Edge ST5 allows you to add relationships to these “dumb” models.

Let’s start with my usual disclaimer. Solid Edge ST5 includes over 1,300 customer-requested changes alone. I can’t even list all of the new features let alone describe them, but here are a few of the major changes and additions that you might find interesting.

The first thing to note about Solid Edge ST5 is that it no longer supports Windows XT. You must be running Vista (ewww!) or later. 32-bit or 64-bit versions are available.

Many mechanical parts, especially sheet-metal ones, include slots. These slots are often not straight but include a variety of turns and curves, and it can be quite time-consuming to create a suitable sketch for them. Solid Edge ST5 introduces a new Slot functionality. All you need to do is to define a path for the slot and it does all the rest.

If you’re into modeling consumer products, or if you want to pretty up your industrial designs, then you’ll like ST5’s new ability to create super-smooth surfaces. 

As indicated earlier, Solid Edge will let you add intelligence to dumb models that were exported from other CAD systems. To aid in this process, ST5 now has the ability to recognize holes on imported models as being hole objects so they can be edited as such, rather than just being void spaces in the model.

The next release of almost any 3D modelling software includes functionality to aid in the opening and editing of ever-larger assemblies. With Solid Edge ST5, Siemens claims that 100,000-part assemblies become quite viable. I’m so old I can remember when a parametric modeller that could handle a 250-part assembly was considered to be pretty good.

Solid Edge ST5 adds a number of assembly modelling enhancements. For example, new assembly relationships allow you to connect virtually anything to anything. 

You can create parts that slide along 3D paths, including things like barrel cam assemblies.

Moveable parts can be “glued” together with a new Rigid relationship. Consider the design of a backhoe.

The main boom can swing side to side and up and down under the control of hydraulic cylinders, whose piston rods can slide along the axis of the cylinder body. Now you want to add the secondary boom, which can swing vertically about the end of the main boom.

The problem is that as you move the secondary boom the main boom will also move. In the real world the hydraulic valves for the main boom cylinders can be closed, which would prevent it from moving. The new Rigid relationship can be used to lock the main boom in place.

Solid Edge ST5 supports associative sub-assembly replication, including mirrored and patterned configurations.

The list of enhancements to 2D drawing creation goes on forever, but includes things like the fact that moveable assemblies can now be shown in alternate positions. 

There are now additional controls over the placement and style of hatching in section views, along with a great many improved and added dimensioning capabilities. 

Solid Edge ST5 now includes thermal analysis, new functionality for integration with their Insight product, and support for wire nailboard layouts for creating wiring harnesses.

Not unexpectedly there is now a free iPad viewer app, but the word “cloud” is conspicuously absent from discussions. Hmmm, maybe they’re onto something here…

With its ST5 release, Solid Edge continues to be a formidable competitor in the 3D design market.