Engineers from all disciplines are using computerized libraries to get quick answers to critical questions. General Electric Appliances in Louisville, KY, is helping its engineers gain more plastics knowhow, has put in place an information software program. The software is Know-How from C-Mold, which is also based in Louisville. Engineers can search for pertinent information about a plastics design problem they may be working on and get answers at their desktop. The Invention Machine product, called Knowledgist, reads and understands digital documents stored in its base. The software uses what the company calls semantic processing technology that scans and analyzes a document. Engineers at GE Appliances use a Web-based computerized library to find answers to questions about plastics molding design and manufacture. The software exists on the Internet and is accessible via a Web browser.
Designing and molding parts made of plastic can sometimes be more complicated than metal part design and manufacture, in part because of the complex properties of different types of plastics and the differences in how those plastics have to be molded.
Engineers at General Electric Appliances in Louisville, Ky., for instance, may not have a specific plastics background, but they have a hand in designing the many plastic parts needed for home appliances. To help its engineers gain more plastics knowhow, the company has put in place an information software program.
It is an example of a growing body of software support called knowledge-based systems, which allow engineers to search stored information and published articles or documents for answers to specific questions. The systems function like computerized libraries that include a vast storehouse of information that engineers need as they work. The systems are useful because engineers get quick answers to questions right on their computers.
And answers—usually in the form of lists of helpful documents returned by the computer and available for viewing on the system—are tailored to the questions they have or the issue they want to research. The engineers don’t have to take time from their work to search through reference books or track down an authority on a subject.
The software is Know How from C-Mold, which is also based in Louisville. Know-How has been in use at GE for about a year and contains hundreds of references to information on plastics molding, said Ron White, a computer-aided engineering manager at GE Appliances. Engineers can search for pertinent information about a plastics design problem they may be working on and get answers at their desktop.
The system also cuts a company’s use of paper documents and books, which can be hard to catalog and store and to search through for answers.
Other knowledge-based software sorts information on many aspects of engineering. These systems, such as one from Invention Machine of Boston, also serve as an easily accessible online reference library for engineers.
The Invention Machine product, called Knowledgist, reads and understands digital documents stored in its base. The software uses what the company calls semantic processing technology that scans and analyzes a document. If the document contains information requested by an engineer, the system suggests that document, whether or not it contains the keyword originally typed by the engineer at the start of the search.
This procedure is described as a concept-based document retrieval method, as distinct from a keyword retrieval method. Stefan Kaufmann, a graduate student in linguistics at Stanford University in Stanford, Calif., is at work on methods to further refine retrieval methods.
One problem with a standard keyword retrieval method is the constantly changing jargon used in engineering and in many other fields, Kaufmann said. Concept-based document retrieval helps deal with changing jargon because the system finds the methodology or ideas the engineer is researching rather than focusing on one word. Keyword searches may miss vital documents simply because they don’t contain the search word typed in by the engineer, said Phil George of Invention Machine.
Many engineers who use keywords to search through the documents on their knowledge-based systems receive too many pages and documents as a result of their search, George maintained. The information becomes overwhelming, and sorting through the suggested documents for the particular information they need becomes too time-consuming to be helpful, he said.
Julian Blosiu, a division staff engineer at the NASA Jet Propulsion Laboratory in Pasadena, Calif., uses the Knowledge and Innovation Server software, also from Invention Machine, to gain more understanding of technical problems he knows he’ll face on a particular project, he said. That technology provides access to a large knowledge base of three-dimensional animated scientific effects and technical examples, as well as offering companies a way to share in-house technology knowledge.
“The software has been very effective at solving the types of technical problems we face when developing new instruments for space exploration,” Blosiu said.
The laboratory builds instruments for the robotic exploration of space, he added. In addition, the JPL manages the worldwide Deep Space Network, which communicates with spacecraft and conducts scientific investigations.
The system at GE Appliances focuses specifically on the design and manufacture of plastics. GE Appliances engineers may have taken some college courses that touch on plastics and plastics mold design, but they often don’t have a background specifically tailored to that type of design. Many engineers learn how to work with plastics by trial and error at their jobs, and this is where such a software system comes in handy, White said. When they’re hired by GE Appliances, the designers receive some plastics training, but also continue to learn as they design parts.
Raising Plastics Awareness
White decided to test the software at GE Appliances to raise the level of plastics awareness across the company.
“The other reason I chose it is that it can store knowledge we gained at the company as we’ve designed parts. It can hold lessons we learned and knowledge we gained, and we can get novices up to speed a lot quicker that way,” White said. The system includes a way of storing reports and documents made by GE Appliances engineers.
The software exists on the Internet and is accessible via a Web browser. This means the system can be continually upgraded, with more documents added by C-Mold.
The software contains a repository of useful plastics and manufacturing-related information, including documents that help designers get plastics education, find solutions to problems, and find troubleshooting issues common to the injection molding industry, said Jim Spann, C-Mold’s director of product marketing.
Because of its unique properties as well as the many different types of plastics and molding methods, engineers have a lot to keep in mind as they design these parts, he added.
Engineers must be continually aware of how part design will be affected by the type of plastic used, as well as how the processing method and tooling used during processing will affect part design and the price of manufacture, White said.
“Certain plastics have certain characteristics that you want to use in a particular application,” he said.
GE Appliances makes washers, dryers, ranges, refrigerators, freezers, water filters, and other home appliances, and all of them contain a large number of plastic parts, White said. Not only must plastics designers remain aware of how the part win be used, they also need to keep in mind what White termed “manufacturability concerns” as they work on part design.
“For instance, if designers don’t know plastics, they might design a part with a really thick section,” White said. “But that means you have an increased cycle time on the machine when they’re injection molding the part, and that costs more. So you want to avoid that thick section.”
Injection molding, as the term implies, uses mechanical pressure to drive plastics into a mold.
One of the designer’s goals is to keep part costs low, White said, so designers need an easily available plastics reference. In plastics design, the mold used to create the part must be designed as well, adding another layer to the plastics know-how needed by engineers.
“With plastics, there’s a lot to consider,” White said. “With appliances, you have to select the proper plastics material for the particular application as you design a part.
“For example, with a range, you have high heat requirements that the part must be able to withstand over long lengths of time,” he said. “And for refrigerators you have to design parts for reliable life over 20 years. And you have to make sure they’re resistant to chemicals that might be in the food, such as butters and food oils that get on things like plastic liners.”
But the software also allows companies that use it to add their own content, such as the methods for plastic part design, internal training materials, and professional experiences in part design. This is what White referred to as the ability of the knowledge-based software to hold lessons the company learned in the past.
Retaining Design Information
Engineers at General Electric Appliances who, through trial and error, have found a particular way to design a plastic part as cheaply and effectively as possible, or who have found a shape that works particularly well for a part can post their findings on the system for future designers to read.
This ensures that when staff members leave, the design know-how they gained on the job doesn’t leave with them, White said.
“When the aging workforce retires, this gives you some method of retaining the information that we learned in the past about designing in plastics, so you don’t have to learn these things again and again.” White said. “Say somebody in the past tried to design a part using gas-assist, but it failed for a particular reason. They put that information in the system so no one goes down that particular design path again.”
Gas-assist molding is a specialized molding method that uses pressurized gas to hollow out the thickest area and to create interior hollowed channels that stiffen the part and reduce warping, White said.
The CAE engineers who report to White currently all use the system. The product includes the ability to run simulations of the plastic design under consideration, which allows users to ask what-if questions while using the system. For example, if engineers want to know what would happen if they used a particular type of plastic to make a part, they can search the system to find information about whether that plastic would perform appropriately. Then they can run a simulation of how that plastic would perform.
Before implementing the system, engineers who had questions about working with plastic materials asked plastic experts on staff at GE Appliances or another member of the engineering community with plastics know-how. But there aren’t enough experts in relation to the number of engineers with questions at GE Appliances, White said. He added that engineers now get their questions answered quicker than they did while waiting for a plastics expert to return a call.
And the experts themselves refer to the continually updated information included on the software to double-check the information they pass on to other engineers.
“I’ve shown this to experienced plastics people, and they’ve said, ‘Geez, I forgot a lot of this 20 years ago.’ So this is a way to keep updated,” White said.
At the end of the design process, the system automatically produces a Web-based engineering report that is added to the company’s knowledge base on the system for future designers to access. This automatic report feature is helpful because the report tool helps engineers to convey what they’ve learned in clear, concise language, C-Mold’s Spann said.
For his part, White has said he’s seen a growing number of people throughout GE Appliances interested in using the knowledge-based system.
“Everybody I show it to is excited,” White said. “So far, we’ve used it to make people more aware of all the issues involved in plastics design. Our use of the system is in the infancy stage, but I see it really growing.”