COSMOS. Why Use Analysis Up-Front in the Design Cycle? COSMOSWorks. SolidWorks Corporation. Introduction. Explore Multiple Design Options

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1 WHITE PAPER Why Use Analysis Up-Front in the Design Cycle? COSMOSWorks CONTENTS Introduction Explore Multiple Design Options 1 1 Reduce Physical Prototypes 3 Easy to Learn and Use 4 Optimize Design Performance 5 Conclusion 6 SolidWorks Corporation

2 INTRODUCTION Finite Element Analysis (FEA) used to be performed solely to determine the strength and functionality of completed component and product designs. It was used by people or departments working separately from designer engineers. Today, however, following the introduction of easy-to-use solid modeling programs that enable a high percentage of the design capabilities of high-end CAD systems, a new class of analysis tool emerged: design analysis either integrated or associated with CAD systems based on solid modelers. Explore Multiple Design Options Reduce Physical Prototypes Easy to Learn and Use Optimize Design Performance These design analysis programs, like the CAD programs with which they work, give design engineers a large proportion of the capabilities of full feature systems but tailored for ease-of-use in making improvements in the form, fit, and function of designs throughout the design process. One of the primary benefits of utilizing analysis up-front in the design cycle is the ability to test multiple design options while still in the initial concept phase. CAD-like operation and computer-based training make the new programs quickly productive, even for users who have little or no analysis experience. And instead of being an after-the-event-of-design function, design analysis now offers what its name implies a design tool capable of saving time, money and effort. Although some design engineers may still be afraid to use design analysis, those who do are quick to praise its benefits. We ve spoken with customers in a variety of industries about their experiences to see how engineers are incorporating design analysis early in the design cycle and reaping the benefits. 1) Explore Multiple Design Options One of the primary benefits of utilizing analysis up-front in the design cycle is the ability to test multiple design options while still in the initial concept phase. Analysis allows you to eliminate impractical or unacceptable designs early on, before excessive engineering resources and manhours have been invested in those designs. COSMOS makes it easy to compare multiple design scenerios. WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 1

3 Gary Passon, a Los Angeles-based engineer who uses COSMOS design analysis during the design of an experimental aircraft, says, Analysis lets us determine how much material a design will need, while still forming the design concept. Passon takes a top-down approach to the engineering process, which he describes as starting with the biggest or hardest part of a design and breaking it down into components. Often, he determines the hardest part of the design with analysis. A piece of a rotor head proved to be the most stressed part of the aircraft design, he says. Because analysis helped him identify that stress, it was easier for him to move to the next most stressed part, and on down the line. The higheststressed component becomes the project driver, and if you follow the load path through adjacent components and they become progressively less difficult, you the designer need to spend less time on them. The more an engineer can learn about the likely behavior of the most heavily stressed parts of his design, the more likely he is to design a good-performing product in the least possible amount of time. In other words, the more an engineer can learn about the likely behavior of the most heavily stressed parts of his design, the more likely he is to design a good-performing product in the least possible amount of time. And time often proves to be the crux and greatest justification for using design analysis early and frequently in the design process. Gary Passon points out that some of the features of modern design analysis programs, such as automatic meshers working on high capacity computers, make it easier for people with limited training to use analysis. He also believes that more familiar the user is with the associated CAD program, the easier it will be to use design analysis. And, as they work with the systems, novices become experienced users. I ve found that weird answers usually can be fixed through some local mesh refining. He finds that it doesn t take long to get the hang of it. To complete a design in a timely manner, you need to know as much as possible about the likely behavior of the most heavily stressed parts of the design, and design analysis helps identify them. The highest-stressed component becomes the project driver, and lets you follow the load path through adjacent parts and as they become progressively less difficult, you need to spend less time on them. WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 2

4 Passon says: You learn to spot it when you get answers that don t make sense. I ve found that weird answers usually can be fixed through some local mesh refining. It doesn t take long to get the hang of it. In our case, it helped us determine how much material the design would need, while still forming the design concept. 2) Reduce Physical Prototypes In some situations, design analysis can eliminate generations of physical prototypes. When you consider the time and expense involved in each prototype, the benefits of eliminating even a single iteration of prototypes from the design process can be seen immediately. Switch Bindings, San Francisco, makes step-in snowboard bindings. Jeff Sand, vice president, says, We perform analysis from the first model up to the first tooling run, and may fill a five gigabyte drive with computer tests. Analysis brings information to the design process that would be very expensive to acquire through physical testing alone. Analysis brings information to the design process that would be very expensive to acquire through physical testing alone. Switch Bindings does make rapid prototypes for physical testing, but prefers in efforts to minimize the time spent bringing new products to market to look at ten variations of design every week with analysis. The information we get through using COSMOS takes a lot of the unknowns out of our way. It doesn t eliminate all of them, but it certainly helps to minimize them. Using COSMOS has enabled Switch Bindings to dramatically reduce the number of physical prototypes. Professional analysts and vendors of high-end, production-level FEA programs often complain that all FEA programs require a great deal of education, and should not be used by people without higher educational training. After all, they say, as is the case with so many computer-based disciplines, if you put garbage in, you ll get garbage out. Analysis allows you to look at multiple design iterations in the time it takes to create one physical prototype. Analysis saves the cost of making at least a few rounds of physical models, resulting in cost savings on the average of $5,000 to $10,000 in the case of Switch Bindings. WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 3

5 3) Easy to Learn and Use Originally introduced in 1982, COSMOS was the first finite element analysis tool available for the PC. Previously, analysis was only available for high-end workstations. Twenty years later, the next generation of COSMOS software continues to make analysis more accessible for every day engineers. Even inexperienced users can learn how to use these systems effectively as demonstrated recently by high school student Eric Klausner. Eric and his friend Brian Blake, students at Voorhees High School, Glen Gardener, NJ, recently designed a BattleBot using CAE software, including COSMOS design analysis. They then built it, with the help of Eric s father, for tournament use. The next generation of COSMOS software continues to make analysis more accessible for every day engineers. This inverted wedge robot was designed by high school students and tested with COSMOS. Eric ran the analyses, and says of the design, It s an inverted wedge that has a usable battle wedge even when it s flipped over. We tried to keep the design simple. I used the analysis software to simulate battle conditions for example, a pulverizing hit by a 2000 lb. weight, such as what would happen to the BattleBot if a VW Bug were dropped on it. He also simulated side impacts, and how the BattleBot would be affected if it were dropped. The program was really simple to learn, he says. The software includes tutorials and gives all the parts for the tutorials. It has a very friendly interface, and works just by point and click. Learning it was so fast, in fact, that I started to analyze the frame of the BattleBot after just two tutorials. Eric, who wants to become a structural or mechanical engineer in the future, offers this advice to other novice analysis users: Have an open mind. As well as working with the tutorials, you can test your results with trial and error. The software was simple to learn, because it includes tutorials and gives all the necessary parts for the tutorials. Learning it was so fast that he began to analyze the BattleBot s frame after two tutorials. Klausner says: Have an open mind. You can always test your results with trial and error. WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 4

6 4) Optimize Design Performance Analysis is only beneficial if it delivers meaningful results. In some circumstances, the real-world operating conditions of the design are so extreme that you have to rely upon virtual analysis to determine whether the design can survive the stresses or not. Alliance Spacesystems Inc. (ASI) is responsible for a much, much more complex robotic design the front arm of the Jet Propulsion Laboratory s Mars Exploration Rover (MER). The MER s robotic arm measures four feet in length, has five degrees of freedom, and carries a variety of scientific instrumentation at the end. Despite its complexity, the arm weighs only 7.7 lbs. because, says ASI president Jim Staats, mass is the most critical part of any space mission. In the case of the MER, the protective aeroshell can hold only a limited amount of mass, he points out, and adds, You just can t get there from here if you can t get the mass within the envelope. COSMOS design analysis helped ASI s design engineers to perform detailed stress analysis that let them minimize the mass of the arm s parts. These tools have become a communication tool between the two types of engineers. "Using some of the optimization features in the analysis tool," says ASI vice president Jim Staats, "we can typically take 15-20% additional mass out." That doesn't sound like much, but if you wanted to reduce your car 20%, he observes, "You'd have to take the whole engine and transmission and throw it out. So it's a big chunk." COSMOS is the tool that makes that possible. COSMOS allowed ASI to eliminated 20% of the mass of the Mars Rover's robot arms, without compromising performance. Besides ASI's design engineers doing more analysis with COSMOS, its analysts are becoming more familiar with CAD tools. "These tools have become a communication tool between the two types of engineers," says Staats. "They both speak each other's language better than I've ever seen before." Training time was virtually nil, and people could do something useful with the program after an hour. You have very young engineers doing what I believe are very advanced analyses, says Staats, and we re getting better designs as a result. Training time was virtually nil and people could do something useful with the program after an hour. With this kind of software, you can have very young engineers doing what I believe are very advanced analyses. Staats says: We re getting better designs as a result. WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 5

7 Conclusion So, is the move to integrating analysis into your design process a sound business decision? Your answer may depend on a variety of factors, but for thousands of your colleagues and competitors, the answer is a resounding yes. Even though COSMOS is saving Switch Bindings an average of $5,000 - $10,000 per design, the cost savings are less important to Sand than the ability COSMOS gives the company to create more and better products. He said, "The most important thing about COSMOS is that it helps us make better and often more products." Staats concludes that COSMOS has helped ASI in the marketplace because the company can crank out designs faster. The software gives ASI a competitive advantage. "But our main thrust is to get parts that are better," he says, and COSMOS does that too. For more information on how you can put the power of design analysis to work for your designs, please visit the COSMOS website at WHY USE ANALYSIS UP-FRONT IN THE DESIGN CYCLE? no. 6

8 SolidWorks Corporation 300 Baker Avenue Concord, MA USA Phone: Outside the US: Fax: info@solidworks.com SolidWorks Europe Phone: Fax: infoeurope@solidworks.com SolidWorks Asia/Pacific Phone: Fax: infoap@solidworks.com SolidWorks Latin America Phone: Fax: infola@solidworks.com COSMOS Wilshire Blvd., Suite 700 Los Angeles, CA Phone: Outside the US: Fax: info@srac.com For additional information about COSMOS products, check out the COSMOS website SolidWorks Corporation SolidWorks is a registered trademark of SolidWorks Corporation. COSMOS is a registered trademark of Structural Research and Analysis Corporation. All other company and product names are trademarks or registered trademarks of their respective owners Structural Research and Analysis Corporation. All rights reserved.