Surprising Results: Digital Prototyping Tests Compare Inventor and SolidWorks

[Full disclosure: Autodesk paid TechniCom to perform these tests and to document the results in this report. The following feature is an extract taken from a detailed report published on TechniCom.]

In August 2010, TechniCom Group published a report comparing Autodesk Inventor and Dassault Systemes SolidWorks using TechniCom’s Delphi Expert Analysis methodology.

The results of this report were somewhat controversial; Autodesk Inventor scored better in all fifteen categories considered than did SolidWorks.

The scoring for the Delphi Expert report was the result of a very detailed survey of eight expert users of the two systems, four experts for each system. The experts had comparable familiarity with their systems and comparable backgrounds.

Readers of that report evidenced hunger for more detailed information, one that might be less sensitive to opinions and be more factual.

Automated ejector placement in Inventor (L) vs. manual placement in SolidWorks (R).

Automated ejector placement in Inventor (L) vs. manual placement in SolidWorks (R).

As a result, TechniCom worked with Autodesk to develop a series of tests between the two systems that might expose the differences between the two systems and perhaps highlight advantages Inventor might have as compared to SolidWorks.

Deciding what to test

First we had to decide what to test and the scope of the testing. Autodesk’s mechanical philosophy is to eschew developing PLM software in favor of digital prototyping. The term “Digital Prototyping” has led to some confusion in the industry.

One clear definition comes from IDC in a paper entitled “Digital Prototyping: Autodesk Strengthens Competitiveness of Worldwide SMB Manufacturers", published October 2008.

This whitepaper differentiates digital prototyping from PLM by noting that "PLM reaches from a product’s cradle to its grave.

"On the other hand, digital prototyping stops at the completion of the digital product and its engineering bill of materials . . . The beauty of digital prototyping is that designs can be tested out before they go to manufacturing."

Thus, Autodesk’s definition of digital prototyping includes the basic functions of PLM — industrial design, design and engineering, data vaulting and collaboration, without the post-manufacturing baggage.

Autodesk has been carefully steering its Inventor software product development over the past few years to enable workflows that take maximum advantage of seamlessly passing data among its built-in application solutions.

Thus, what we see in Inventor today is a careful melding of technologies that Autodesk has acquired or built. Many of these technologies are not available as extra cost add-ons to the base software, but fully included as part of the Inventor software.

Inventor and SolidWorks parting surface generation.

Inventor and SolidWorks parting surface generation.

Some example, of which you will see more later, include mold analysis software, mold base design capabilities, built-in advanced simulation, inherent design automation options, an intelligent part library, built-in engineering calculations and many others.

Not only are these available as an integrated part of Autodesk Inventor, but they are often combined to form workflows that aid in developing the digital engineering models.

Thus, when deciding the scope of what to test, we settled on a series of tests that focus on the areas in our Delphi Expert analysis where Inventor rated the highest.

These areas include the following:
1. Plastic Part Design
2. Plastic Injection Mold Design
3. Assembly Design and Analysis
4. Exporting BIM-ready Models
5. Interoperability
6. Design Automation
7. Mechatronics

Even deciding on these seven areas leaves a great many options to be tested. Autodesk decided on the detailed functions to be tested. Autodesk has specified the seven tests in detail.

They are aimed at comparing the two systems ability to perform common, real-world engineering workflows.

These tests are not designed to be impartial; they are taken from standard demos used by Autodesk that were designed to represent a series of engineering workflows highlighting Inventor’s digital prototyping capabilities.

Most of them, as the users can see below, are aimed at performing a complete design sequence. We have included, in the following seven sections, the details of what we tested, images and videos of the results, what we observed comparing the two systems, and our summary of how well each system was able to perform the desired workflow.

Tests specified by Autodesk

Autodesk provided TechniCom with the test definitions including videos of Inventor performing the desired task, starter geometry, related dimensions, and other relevant data, all described below within each test section.

TechniCom’s task was to perform the same tests using SolidWorks Premium 2011. Because Autodesk provided much of the model data we were able to focus on the desired workflow details of each test, rather than building geometry.

TechniCom’s approach

TechniCom, in collaboration with a Certified SolidWorks Professional (CSWP) performed and analysed these tests during November and December 2010 using Inventor Professional 2011 and SolidWorks Premium 2011.

To make the scope reasonable, we limited each vendor’s software strictly to what was included with the package or third party add-ins that we were able to find and download free of charge.

As input, we used the Inventor videos illustrating the work to be performed. We attempted to deliver the same results using SolidWorks Premium 2011, as did Inventor.

We are making available to the readers of this report, annotated videos of both Inventor and SolidWorks performing the tests on TechniCom’s blog. Readers wanting to understand how the two products compared have the unique ability to review these videos along with reading our test summaries in this report.

[We remind the reader that we compared Inventor Professional 2011 versus SolidWorks Premium 2011 with the restriction that extra cost third party software was not to be considered. When we were able, we used no-charge third party add-ins for SolidWorks — none were needed for Inventor.]

Summary of the test results

In the first two tests, plastic part design and injection mold design, Inventor clearly outclasses SolidWorks. Whereas Inventor completed all aspects of the test, SolidWorks was unable to complete major portions of the analysis of the part and the mould.

Inventor was also able to design the mold significantly faster than SolidWorks due to the inclusion of automated tools for designing the various subsystems of the mould.

For the assembly design and analysis test, both systems were able to model the addition of a clevis pin. However, Inventor excelled in its ability to design the correct pin by coupling its engineering calculation library to the potential design.

In other words, Inventor helped select the correct pin size because it was able to use its calculations concerning the required TechniCom Tests Digital Prototyping Workflows Comparing Inventor and SolidWorks stress that the pin would need to perform correctly.

This is subtly different than SolidWorks, which used its library to size the pin, but without taking into account its stress requirements. The SolidWorks approach was to design the pin and then analyse it in an iterative fashion using its built-in FEA solution until the specifications were met.

In this case SolidWorks was unable to verify that its built-in FEA solution was correct. A more advanced version of the FEA solver would have been required; concomitant with more advanced engineering skill.

The latest release of SolidWorks added some BIM exchange capabilities, but Inventor’s BIM data transfer capabilities exceeded SolidWorks in key areas important to building designers.

These included specifying connection points and component types that are carried over to the BIM-designer’s software. In addition, the mechanical designer using SolidWorks had a more difficult time orientating the model and simplifying a non-native model for export.

Design Accelerator in Inventor (L) and SimulationXpress environment in SolidWorks (R).

Design Accelerator in Inventor (L) and SimulationXpress environment in SolidWorks (R).

Our test of CATIA interoperability and direct modeling on imported models reiterated the widely known issue that SolidWorks does not directly import a native CATIA V5 file, even though both products are part of the same company.

Direct modeling was comparable for both Inventor and SolidWorks, with SolidWorks being a little easier to use for the simple direct model changes we made. The SolidWorks drawing output in DWG format produced an incorrect dimension in a scaled view.

For design automation, our tests revealed two weaknesses of SolidWorks. SolidWorks with DriveWorksXpress was not able to automatically scale drawing views to fit a part within the confines of a drawing after the size of the part was changed. Manual intervention was necessary.

Modifying the geometry in Inventor Fusion (L) and SolidWorks (R).

Modifying the geometry in Inventor Fusion (L) and SolidWorks (R).

A second weakness was shown when scaling a copied assembly using 3D curves to define key points as the assembly was copied and scaled to other planes. Inventor was easily able to scale a copied assembly using drive curves; SolidWorks could, but required significant manual effort.

Both systems proved to be comparable in mechatronics where we tested the ability to build wire harnesses using schematic input from electrical software packages, albeit Inventor was able to do so with many fewer interactions.

Conclusions

Ray Kurland, President of TechniCom knew that the tests were meant to highlight Inventor strengths, but was surprised that SolidWorks Premium 2011 was, in many tests, not able to do the work without adding pricey third party software.

Duplicating Inventor’s capability on these tests with third party products will also make SolidWorks substantially more expensive than Inventor.

These seven tests underscore our contention from our previous Delphi Expert Analysis, that Inventor is a mature system that can more than effectively compete with SolidWorks and should definitely be considered for even the most complex situations.

The Inventor workflows illustrated in this series of tests are integrated and highly logical, enabling users to accomplish their design goals with minimal effort. Beyond that, we hope to have shown the value of Autodesk’s digital prototyping emphasis, which we expect will continue to evolve even further.

“I didn’t know that Inventor had this much functionality,” said TechniCom Group’s associate performing the tests, a CSWP. “I know that they acquired a lot of technology over the past few years, but I am surprised to see it all integrated so well into Inventor.”

Overall, TechniCom is most impressed with Inventor and the direction Autodesk is taking for the future. To keep abreast with our continued tracking of the industry and our reactions to Autodesk’s direction we advise readers to follow our blog and twitter feeds.

Download the full report.

About the author
Raymond Kurland is president of TechniCom Group and its principal consultant and editor. His firm, founded in 1989, specialises in analysing MCAD and PLM systems and has been involved in reviewing and comparing such software since 1987. Based in New Jersey, Ray frequently consults with both vendors and users. Ray has degrees in Engineering from Rutgers University and from NYU. His career included stints with Bell Telephone Laboratories, IBM and Dassault Systemes.