FEA Leads Companies to Better Products in Less Time

It doesn't take any skill to cut product design costs: just cut time and material, and costs go down. The skill is in cutting time and material while producing better products-the eternal conflict that pits companies' engineering managers against financial managers.

Desktop analysis software gives engineering managers and executives an ally in their challenge to help companies' bottom lines without sacrificing quality and sound engineering practices. Analysis applications enable designers anywhere in the product development process to test how their designs will behave as physical objects before prototyping or full production. Catching and correcting errors when a design is still on the computer screen takes just minutes, while fixing a prototype or a finished product can halt production for days or weeks.

Used throughout the design process, analysis software enables engineers of any skill level to optimize designs for best material use and root out errors early in the design process, rather than later when they cost more time and money. Analysis software is not just for experts anymore. It turns every designer into a quality control cop, replacing dependence on specialized analysts and also on over-designing, a persistent seat of unnecessary expenses. Companies using analysis software throughout the design process typically have fewer costly late-stage design errors, need fewer physical prototypes to validate their designs and encounter almost no post-production problems. Faster time-to-market gives these companies an advantage over competition.

Barriers to FEA Adoption May Be Cultural

The current ranks of engineering managers and executives know about analysis software, at least in concept. It has been around since the 1960s, when aerospace engineers adopted it to analyze aircraft designs. However, those complicated, expensive applications bear no resemblance to the affordable, easy-to-use analysis software available today. Engineering managers owe themselves and their companies a new look at this promising technology up close. The first step toward the higher profit margins and superior quality is for engineering management to update their own knowledge about analysis software.

Proven Technology Gains Broader Appeal

In its earlier iterations, FEA software was relatively expensive and ran only on mainframes or specialized workstations, which yielded numeric results analysts would interpret for the designers. By the 1990s, analysis software came out of the back room to run on desktops and displayed 3-D images rather than numeric data. Analysis was, however, still mainly the domain of specialized analysts.

Large and small shops that couldn't afford the software and specialized staff relied on some combination of hand-calculated analysis, outsourcing and physical prototyping to test their designs. Most shops over-designed their products to ensure they met physical requirements. Though over-designing usually yields sturdy products, higher material costs erode profit margins.

Unable to absorb the lower profit margins as readily as large companies, small companies began using FEA software to analyze their designs throughout the process, pinpointing problems and optimizing designs for efficient material use. Today, companies use analysis software to cut time and materials while developing superior products.

In an April 2003 survey of one thousand analysis software users, SolidWorks Corporation (Los Angeles, CA) found that 67 percent of users credited the software with improved product quality. More than 59 percent of respondents said they were able to avoid field failures by using analysis software; 56 percent used fewer prototypes; and 15 percent of respondents indicated that they were able to avoid product recalls completely by catching mistakes early in the design process. These quality gains go hand-in-hand with timesavings. A typical FEA application can analyze a sixty- to seventy thousand-element model in under three minutes.

Greg Cook, principal of Cook Engineering Services, Inc. (Glendale, CA) responds to clients' calls with a notebook computer in hand. When an amusement park client called with a problem on one of its roller coasters, Cook was able to take measurements, create a solid model and complete a finite element analysis on-site to validate the proposed repair.

"The power and flexibility I get from state-of-the-art analysis software running on a notebook enables me to provide my customers with detailed and accurate analyses of their designs and offer suggestions for improvements right on the shop floor," Cook says. "This level of efficiency was not possible ten years ago. The ability to use one solid model for visualization, dynamic simulation, finite element analysis and drawing preparation has shortened the design process immensely."

Pasadena, CA-based Alliance Spacesystems, Inc. (ASI) designed the robotic arm for the new generation of NASA Mars probes. All of the probes' components had to meet weight and rigidity guidelines to ensure the probes were not too heavy to make a safe landing on Mars' surface. In addition, the company had firm deadlines for designing and building an arm. ASI used analysis software to pare down a robotic arm's weight during the design cycle, before physical prototyping. A robotic arm also had to meet stiffness requirements so it could operate scientific instruments with precision, such as scrapers to take rock samples. ASI's engineers used optimization software for detailed stress analysis of an arm's parts. The engineers varied the parts' geometry to reduce mass while controlling the maximum allowable stress or deflection.

"Using some of the optimization features, we can typically take 15 to 20 percent additional mass out," says ASI Vice President of Engineering Jim Staats. "That doesn't sound like much, but if you wanted to reduce your car's mass by 20 percent, you'd have to take out the whole engine and transmission, so it's a big chunk."

Sub-Atlantic Company (Aberdeen, Scotland) develops remote-controlled submersible vehicles used in undersea oil exploration and marine research. The company recently designed the Navajo-a lightweight, low-cost submersible to supplement its high-end products. Sub-Atlantic wanted the Navajo to weigh no more than seventy pounds so it could be launched by hand from a small boat with no special equipment. The company used analysis software to cut down on the Navajo's weight and test the durability of its control housing under various depths of ocean water.

"Once engineers produce designs, the analysis software tells them how they will behave in real-world conditions. The subs are designed to be weight-neutral in water so they can descend or rise according to the surface operator's instructions," explains Colin Millum, Sub-Atlantic's director of mechanical engineering and design. "Analysis software lets us anticipate where high stresses occur and optimize the design by adding or removing buoyancy elements so that, above water, the vessels are as light as possible."

Combining Technology With Good Management

Regardless of how advanced analysis software has become, it can't replace human analysts. Nor should it. Some tasks are simply too specialized for anyone but a highly trained analyst. However, analysts should not be bogged down with small, noncritical analyses. Why have an analyst test a small part in a complicated assembly when a designer can do it, leaving the analyst to concentrate on the assembly's overall performance? Software can eliminate the congestion that slows the design process and inflates costs in most companies. Integrating analysis into design processes is a matter not just of technology, but also of good management.

Analysis software works most effectively in a framework of best practices. It's not enough to give design engineers easy-to-use software and tell them to analyze their designs. They need explicit guidance about what to look for when analyzing a design. They also should not be doing complex analyses beyond their expertise. Engineering management's role is to work with analysts to define best practices, then to enforce them throughout the design process. By clearly establishing roles and expectations, engineering managers and executives can use FEA software to fulfill their primary roles as guardians of quality while cutting time and waste from product design.