Quality Applications

Tecnomatix eM-TolMate Software Benefits Designs and predicts the effects of tolerances on the assembly process Analyzes measured data against    design specifications Can eliminate the need for design prototypes www.tecnomatix.com

Aircraft Quality Soars with Software
Tecnomatix eM-TolMate Software

Lockheed Martin Aeronautics Co., located in Fort Worth, Texas, needed a means to reduce unit recurring cost, meet aggressive production goals and improve fighter aircraft quality. The company, which works on design, development, systems integration and support of fighter aircraft employed by U.S. and allied nations' militaries, turned to Tecnomatix's eM-TolMate (a module in eMPower Quality Solutions) to test assembly designs for dimensional performance in the preliminary design phase of new fighter programs. Lockheed Martin uses the software to ensure that an assembly scheme will meet customers' requirements and that tolerances are accurately specified during
design and fully adhered to during manufacturing and assembly processes.

 "Tecnomatix's eM-TolMate is a cornerstone of our variation management design method," says Randy Schwemmin, Advanced Affordability Initiative manufacturing engineer at Lockheed Martin. "It has helped us optimize the relationship between customer requirements of the air vehicle and the manufacturing quality of its assemblies."

 Lockheed Martin's variation management design method is a four-step process that begins with the identification of customer requirements, the specifications that drive each assembly process. The second step is a more creative undertaking, wherein engineers generate a pool of assembly options. The options are then evaluated against each other. Finally, eM-TolMate produces simulation results for analysis, which are compared to the customer's requirements.

 Prior to using eM-TolMate, Lockheed Martin's manufacturing engineers would perform time-consuming and labor-intensive rudimentary, linear and worst-case tolerance calculations. At times, assemblywide tolerance analysis was overlooked altogether. The company began to research alternatives to its existing tolerance analysis procedures and came upon eM-TolMate. It offered what became Lockheed Martin's first top-down assembly approach, wherein assembly strategies are created before the designs are finalized--what Schwemmin calls a "radical change" from previous design methods. When comparing it to other tolerance-management products, users at Lockheed Martin found eM-TolMate to be extremely intuitive and straightforward, making it easier to learn and teach to others.

 The software is designed to define, predict, measure and analyze tolerances throughout the industrial process. It helps ensure that tolerances are correctly specified during the design phase and fully adhered to during the manufacturing and assembly processes. At every stage of the industrial process, the broad range of eM-TolMate tools provides a dedicated solution to minimize variation, reduce engineering changes and help ensure that parts are manufactured according to the designer's intent.

 The set of software tools uses softgauge, a 3-D electronic image of a part's tolerance zone, to define and store specified tolerances for a manufactured part. The softgauge is stored within the master CAD model and is used throughout the process. With this master CAD model, users are able to define tolerances and predict the effect of tolerances and the sequence on the assembly processes, create offline inspection programs, measure components on a coordinate measuring machine or numeric controlled machine, and analyze measured data against design specifications.

 Tecnomatix has also been invaluable in helping users at Lockheed Martin to make eM-TolMate work for their specific applications. "Airplanes are very different from other assemblies, with contoured, complex surfaces and complex features," explains Schwemmin. "Modeling has been very difficult for us, but we've been extremely pleased with the amount of support Tecnomatix has given us."

 Lockheed Martin's benefits from using Tecnomatix's software, from reducing recurring costs to streamlining production processes, are impressive. "Significant improvements resulted when Lockheed Martin used variation management methods along with other advanced assembly technologies in an alternative design of the F-16 forward equipment bay," says Schwemmin. "The part count was reduced from 90 to 22, the fastener count was reduced from 1,155 to 251, the tool count was reduced from 206 to 32 and the recurring assembly cost was reduced from $37,500 to $20,900 per unit. The software provides us with a method for testing designs without prototypes, cutting cycle time and cost. It also gives us practice in creating design-build-inspect-improve process cycles that use only digital data. This practice will revolutionize our approach to product design."