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Jeffrey Rowe has over 35 years of experience in all aspects of electro-mechanical design, engineering, and manufacturing. On the publishing side, he has written well over 500 articles for CAD and other technical publications, as well as consulting in many capacities in the MCAD community. As editor … More »
Introducing CAE Into Your CAD/CAM Workflow: Look Before You Leap
January 27th, 2012 by Jeff Rowe
There are several types of CAE-related manufacturing applications for optimizing the use of materials, tools, shape and time, and machine layout by simulating and analyzing specific manufacturing processes. However, probably the most common method for getting CAE into a manufacturing environment, finite element analysis (FEA) for parts and tooling.
FEA is a numerical technique for calculating the strength and behavior of structures. It can be used to calculate deflection, stress, vibration, buckling, and other behaviors. Typical applications for FEA would include minimizing weight and/or maximizing the strength of a part or assembly.
In FEA, structures are divided into small, simple units, called elements. While the behavior of individual elements can be described with a relatively simple set of equations, a large set of simultaneous equations are required to describe the behavior of a complex structure. When the equations are solved, the computer and FEA tool displays the physical behavior of the structure based on the individual elements.
FEA tools can be used for innovating or optimizing mechanical designs. Optimization is a process for improving a design that results in the best physical properties for minimum cost. However, optimization using FEA tools can prove difficult, because each design variation takes time to evaluate, making iterative optimization time consuming. On the other hand, FEA tools can really shine when seeking new and unique ways of designing things – the most crucial aspect of innovation.
Before committing to any CAE tool, however, be sure it is compatible with your existing CAD and CAM tools, the types of parts and assemblies you design, and your general workflow.
Keep in mind that there is no one tool that serves everyone’s needs. Some will be interested fluid flow, others in structural mechanical properties, and still others in thermal issues. Get input from as many groups within your organization as are likely to benefit from CAE tools. When evaluating CAE tools, make sure you evaluate them with your models; not just models supplied by a vendor. That way, you’ll be able to objectively evaluate different CAE tools that best suit your needs in your environment, and not be overly swayed by what a vendor wants you to see. Obviously, it’s in your best interest for objectivity to use the same parts or assemblies with different CAE tool vendors.
Finally, a word of caution. Don’t expect CAE tools to solve all your problems with all of your parts. Like CAD and CAM tools, they should be used in conjunction with experience and common sense to arrive at optimized and innovative designs. Calculating return on investment when using CAE tools can be as complicated as performing analyses on complex assemblies. However, you can probably count on estimating ROI from time saved during the design process, lower material costs, reduced numbers of physical prototypes and ECOs, and possibly greatly reducing the number of product liability lawsuits. CAE tools cannot perform miracles by themselves because they still require a significant human element, but employed wisely, will likely improve your workflow and provide tangible benefits.