Cadalyst Labs Review: Alibre Design31 May, 2006 By: IDSA ,Mike Hudspeth
Mechanical design modeling in 3D
You might remember that last year a mystery company came out with a 3D modeler called X-CAD that it provided for free to the first 100,000 people who registered. That company turned out to be Alibre. It got its 100,000 registrations and introduced a lot of folks to 3D modeling. X-CAD is now called Alibre Design Xpress, and Alibre continues to give it away for free.
Why go through all this trouble for something that won't make any money? Alibre Design Xpress is the proverbial hook. It offers some nice capabilities but also has many limitations. After you get used to what it can do, you're going to want more—Alibre Design 9, to be specific.
Alibre Design 9
Ready . . . Aim . . . Model
Alibre Design 9 is aimed at small- to midsized mechanical shops that perform detail design, although Alibre is picking up some larger companies that use the software for conceptual design. Alibre isn't touting its software as a replacement for whatever design software a company already has, but rather as a complement to it. Whatever you use it for, it's got some impressive capabilities. For instance, take configurations (figure 1). The ability to model different configurations of your products is not groundbreaking in and of itself; SolidWorks has had that ability for years. With Alibre Design 9, users can take care of families of parts and in-process features. You know how the process goes. You start with a blank and as it goes down the assembly line you have to bend it, drill it, weld something to it, and so on. Alibre lets you do it all in the same file. Not only that—your configurations go right into drafting and BOMs (bills of material).
Figure 1. Alibre Design 9 lets users create different configurations of a model so they can keep track of similar models without using multiple files.
Alibre Design's sheet-metal capabilities include overlapping flanges and common punch-press patterns that can be used for cooling, weight reduction and fastener locations. Wonderfully complex designs are possible, and Alibre Design can unfold them into flat patterns to be cut or stamped.
I See a Pattern Developing
Alibre Design 9 treats patterns in a new way. Users are no longer restricted to rotational and linear patterns. They can create a sketch to drive patterns, put features exactly where they want them and control them to a much greater degree. Placement, shape, layout and orientation can all be controlled. And users have a library of canned pattern shapes at their disposal to simplify and accelerate their work.
Alibre has expanded its API (application programming interface) to allow easier customization of the program as well as third-party developer support, which means third-party add-ons such as FEA (finite-element analysis) and CAM (computer-aided manufacturing) are just around the corner.
Something's Sketchy Here
Everything in Alibre Design 9 begins with a sketch. The sketcher is based on UGS' D-Cubed constraint manager (www.ugs.com/products/open/d-cubed). Users can create a sketch in either 2D or 3D. Intelligent constraints examine what is being sketched and infer relationships. All the usual constraints are available: fixed, vertical, horizontal and tangent. Users can refine sketches with trims, extends and so forth. One feature I particularly like is the ability to make copies and patterns of sketch entities. Users also can create dimensional constraints based on absolute values they enter, equations tied to other dimensions or geometry and even spreadsheets on a hard drive or network.
Alibre Design 9 is a parametric—that is, dimension-driven—modeler based on the industry-standard ACIS modeling kernel. As such, users get all the standard functionality: extrudes, revolves, lofts and sweeps. You can add, subtract, and intersect solids.
Reference surfaces can be wonderful things. For instance, if users can pull in a sculpted surface, they don't have to build it themselves, and that also can ensure that a surface isn't changed accidentally. After developing a reference surface in Alibre Design 9, you can use it for all sorts of things: extrude to it, sweep to it, trim with it and even thicken it into a solid body.
Figure 2. You can create wonderfully complex assemblies in Alibre Design 9. They can be controlled bidirectionally from the assembly and from the component part level.
Alibre Design 9 allows users to approach assemblies in two ways: top-down and bottom-up. Top-down means you start your design in the context of the assembly and then build all the parts in one place and save them to their component part files (figure 2). Bottom-up assembly is just the opposite. You model each part and bring them into one assembly file. Either way, you can combine parts and constrain them to act in prescribed ways. Alibre Design 9 can even auto-constrain for you, so putting your assembly together is much simpler. It's easy to create exploded views to illustrate how to put your device together (figure 3)—either tell Alibre Design 9 to auto-explode (no, not like a tape recorder in Mission Impossible) or drag components to where you want them.
Figure 3. It s easy to set up exploded views that show how a design goes together. The exploded view can then be brought onto a drawing.
I Feel a Draft
Once your model is satisfactorily built, you can create drawings. As a solid modeler, Alibre Design 9 will never fudge on the drawing views. Remember using the drafting board? You were always finding discrepancies between views, and when a change was made, you had to update each and every view by hand. Alibre Design 9 can create standard orthographic views automatically from the model, and they change when the model changes. The views always stay up to date. You also can add other standard types of views: detail views, section views and broken views. Remember that exploded view I discussed before? You can bring it onto the drawing, populate it with bubble callouts and create a BOM that, like the views, is based on the assembly and will always agree with it (figure 4).
Figure 4. You can have shaded views, exploded views and normal orthographic views on a drawing. They always update with the model.
Can You Hear Me Now?
Because Alibre Design 9 is based on the STEP model data file format, interoperability should be no problem. Alibre files should be usable in most programs that use STEP. This compatibility makes the files program independent, a very good feature for ensuring future access to legacy data. Of course, Alibre Design can import and export other standard formats such as SAT (ACIS), IGES and DXF/DWG, which makes team collaboration easier.
In today's truly global environment, we must work with people who are not sitting in the next cubicle. Frequently, team members are on another continent. Collaboration is an important thing to foster, and Alibre Design 9 can certainly handle it. In Team Design sessions, multiple Alibre users can work on the same files, sketches, models or drawings at the same time. This enables design reviews of unprecedented value with an entire team, no matter where the members are. A huge plus! You can set up a session like a chat room, where text scrolls in a window, or with VoIP (voice-over-Internet protocol). You can save interactive redlines and markups that include the date, time and author with the part files for later action.
A Heavy-Duty Load?
Alibre Design 9 probably will run on your existing desktop, at least in terms of the operating system. It runs under Windows 2000 (SP2 or later), XP (both Professional and Home versions) and even 98 and ME. No Internet connection is required for normal modeling, but one is needed for Team Design sessions. Obviously, if you're going to model something really complicated, you'll need more computing power (that is, hardware) to handle it.
Getting the Job Done
Alibre Design 9 is a reasonably priced, highly functional mechanical design program that will help you do what you need to do. If you haven't looked at it, you should.
Mike Hudspeth, IDSA, is an industrial designer, artist and author based in St. Louis, Missouri.