A device for aligning and attaching engine components that has been awarded a 1999 R&D 100 Award is the subject of a paper to be presented at asme's International Mechanical Engineering Congress and Exposition this month in Nashville, Tenn.

The award is shared by Martin L. Culpepper, a graduate student in mechanical engineering at Massachusetts Institute of Technology; Alex Slocum, a professor and MacVicar Faculty Fellow at MIT; Robert Rines of Aesop Inc.; and F. Zafar Shaikh, Joe Schim, and Gary Vrsek of Ford. The R&D 100 Awards honor the 100 most technologically significant new products of the year.

The award-winning invention, which grew out of ongoing research in Slocum's mechanical engineering lab, is said to yield a fivefold increase in the precision with which two parts can be aligned. In the production of an engine, the two main components are bolted together and a hole is machined lengthwise between the two. Then the two halves are taken apart again to put in the crankshaft and bearings that fit within the hole.

"When the halves are reassembled (with the crankshaft and bearings in place), it's important that they are lined up to within five millionths of a meter of their original bolted position, or the engine will not work properly or possibly fail," said Culpepper.

Currently, engine manufacturers solve the alignment problem by machining eight holes into each of the main engine components, then fitting them together via dowel pins inserted in the holes. Among other drawbacks, "this design is costly to manufacture as it requires machining/gauging 16 precision holes and eight hollow dowel pins," Slocum said.

"With the new method, dubbed the Kinni-Mate Coupling by its developers, the two major engine components are aligned via three spherical pegs (instead of dowel pins) that are pressed into one of the components. The pegs then "mate" with three corresponding conical holes in the other component.

Compared to other business jets of the same size, the new Premier I from Raytheon Aircraft Co. in Wichita, Kan., is said to be more aerodynamically efficient because of its smooth unbroken surface. The entire fuselage is a monocoque structure made from composite carbon fiber/Êhoneycomb core rather than being assembled from aluminum panels, ribs, and stringers as are conventional aircraft. The design has attracted enough attention so that the waiting list now extends until 2003.

In September, Raytheon announced that it plans to increase production of the Premier I to 60 per year, a 25 percent increase from the 48 per year originally planned. This increased production is possible with the addition of two new Cincinnati Machine Viper fiber placement machines used for the aircraft's composite fuselage. More than 200 Premier I's are on order. The price tag is $4.5 million.

The Premier I's wing has one-piece, milled spars and single-piece aluminum skins. The wing box contains only 180 parts (compared to more than 750 in a traditional light jet), lending it great strength and damage tolerance.

With full fuel, a pilot, and four passengers, the Premier I has a 1,500-nautical-mile range and can take off in less than 3,000 feet. The Premier I is powered by two Williams/Rolls FJ44-2A engines and has a maximum speed of 461 nautical miles per hour (530 statute miles per hour).

Before embarking on the project, Raytheon decided it would fundamentally change the way it designs and builds airplanes. The company's goals were to shorten the design process and arrive at a mature solution far earlier in the cycle (thus reducing cycle time), and to optimize the design to make the most production-cost-effective aircraft possible.

"Digital pre-assembly eliminates conventional physical mockups," said Duncan Koerbel, Premier I program manager. The company had already been using Catia on various projects, but had never applied the CAD/ CAM/CAE application to a major program before. It was decided that the new jet would be designed entirely in Catia.

Raytheon chose IBM ProductManager (now known as EnoviaPM and developed by Enovia Corp., a Dassault Systemes subsidiary) as the product data manager.

The bridge between Catia and EnoviaPM was created by a customized Catia assembly management tool, a joint development effort between IBM and Raytheon, specifically to support the Premier I and future projects. The tool allowed the basic design work performed in Catia to automatically create, update, and manipulate information in the EnoviaPM database to manage items, documents, and bill of material structures. It also allowed Catia designs and other information such as the bill of materials to be grouped together into digital assemblies. For example, a wheel, axle, and landing gear strut, along with associated information, could be logically grouped and treated as a single assembly before being passed on to the factory floor.

Hewlett-Packard Co. and Structured Development & Research Corp. have put together a bundled configuration to implement Ford's C3P (CAD/CAM/CAE/PIM) initiative among supplier companies. The "C3P Quick Start" package includes software, hardware, training, implementation support, and services to help suppliers become competent in the C3P tools and Ford processes required to support product and vehicle programs worldwide.

The C3P Quick Start package includes a C3P Solution Seat from SDRC-C3P software licenses, software training, and on-site technical support services. The package also provides the choice of Hewlett-Packard Visualize Unix or NT workstations. Services include installation and startup at the customer's site. The Quick Start package will be available on a two- or three-year HP Technology Finance Lease. Pricing for bundles starts as low as $900 per month for NT configurations with existing installations. Pricing for Unix configurations is available from Hewlett-Packard.

When Rocketdyne Propulsion & Power of Canoga Park, Calif., a business unit of Boeing, set out to design a speculative combustion chamber and injector for a not-yet-designed rocket engine, it was decided that the ideal members of the team would have world-class expertise in their own fields but no experience in engine design, "because they would come with no baggage," said program manager Bob Carman.

Another reason they would have no baggage is that they would stay where they were, scattered across the country. The team members' lack of preconceptions and their use of Internet-based collaboration software paid off with a design that has six parts instead of about 1,700, that could be produced in nine months instead of two years, and that would cost about $35,000 to make instead of $1.4 million to $1.6 million (for a 60,000-pound-thrust engine), Carman says. Instead of 30 to 40 members, this team had a core of nine. They completed their design in one year instead of two, spending less than one-tenth the amount of previous design projects.

The only cost that has not been cut is that of testing. Rocketdyne has conducted preliminary tests on a new combustion chamber, but will wait to find customers before subjecting the new design to hot-fire testing.

Rocketdyne had assembled a team that included "world-class" specialists from companies dispersed across the United States. Team members were asked to devote no more than 10 percent of their time to the project. Their company affiliations and responsibilities included: Boeing Rocketdyne in Canoga Park: leadership, conceptual design, and combustion and thermal analysis; Raytheon (formerly the Texas Instrument Defense Division) in Dallas: CAD modeling, manufacturing and producibility assessment, and program budget tracking; MacNeal-Schwendler Corp. in Costa Mesa, Calif.: structural analysis; Lockheed Martin in Huntsville, Ala.: launch vehicle requirements; and Howmet Corp. in Whitehall, Mich.: determination of producibility and costs.

After one meeting in person, the team members used pTeam software from Nexprise Inc. of Santa Clara, Calif., to collaborate over the Internet. For instance, they used Notebook to brainstorm a dozen design concepts. The design they settled on was rendered by Pro/Engineeer from Parametric Technology Corp. of Waltham, Mass., and the drawings were uploaded to the Vault, where other team members could view the work in process. A mail program, Mail, notified members when new documents were put in the vault. The design team reached decisions through threaded discussions in Notebook, which can store text, drawings, audio, video, and links to other information.

Through their collaboration, Carman says, the team soon discovered that "one of the major cost drivers is part count." They kept refining the design until it consisted of a manifold, chamber wall, throat, injector plate, and nozzle, held together by the same bolt, "and not one of those exotic $600-apiece-bolts," says Carman.

The CastView program from the North American Die Casting Association can help a designer quickly evaluate a casting that might otherwise require a full simulation.

During the design process, CastView can be used to evaluate the possible locations of mold gates, vents, and overflow, and to determine where thick and thin sections could affect the quality of the finished casting.

A 30-day trial copy of CastView can be requested from NADCA at publications@diecasting.org. NADCA is also offering to convert one STL file of the user's choice. Send an e-mail to robb@diecasting.org with the STL file attached, and the file will be converted and returned via e-mail so that it can be evaluated with CastView.

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