A Product Line Engineering (PLE) approach allows companies to build a product line portfolio as a single production system rather than a multitude of individual products. This approach promises big improvements over the traditional product-center engineering strategy. The upcoming ISO Standard 26580 will establish necessary PLE frameworks and interfaces to primary systems engineering tool suites. To learn more about this shift from product-centric to product line engineering, Design News talked with Dr. Charles Krueger, founder and CEO of BigLever Software, and William J Bolander, Principle Consultant at Methodpark. What follows is a portion of that conversation.
Design News: What is meant by Product Line Engineering? Why is it important to engineers?
Charles Kruger: Consider organizations that build a family of systems or products with a lot of similarities such as common features and functions, but also with differentiating differences among the members of the product family – for example, automobiles, computers, cell phones, airplanes, ships, etc. Such companies try to find efficiencies in product line commonalities while also embracing the variation during the engineering process. That’s actually a good definition of PLE.
William Bolander: PLE is a set of processes, methods, and tools to develop a set of systems from a common set of engineering assets that maximizes reuse while managing their variations. By maximizing the use of strategic reuse of all the engineering assets, companies have been shown to reduce the cost of developing similar systems while increasing their quality.
Design News: Isn’t it the differences, the variations between products that really present the challenge to engineering organizations?
Charles Kruger: Yes, PLE handles that variation by taking advantage of the shared set of common engineering assets such as requirements, designs, source code, electrical design, mechanical design, test cases, documents, and all of those digital artifacts that result from the engineering process. The goal is to have a single copy of all those artifacts so there's never any duplication, copying, merging, branching, or the like. Instead, PLE applies formal models and automation to allow companies to configure and construct different configurations of their digital engineering assets through a feature-based characterization of what's in this product versus that product.
Design News: What kind of tools are available for the modeling and automation of the digital assets? Will a single database be needed?
Charles Kruger: Feature-based, product line engineering tools exist today. Our tool suite is one of them. Also, the ISO 26580 standard being developed will more formally define what it means to have a product line engineering tool. The standard will address both PLE tools that capture the distinguishing characteristics that vary between products as well extensions to existing tools. The goal is to integrate with existing engineering tools and make them more product line aware.
William Bolander: All tools used to engineer a system need to be used in a way to support this approach including requirements, architecture, design, verification and validation, coding, configuration management, etc. The most efficient way to accomplish this is to take advantage of tools that manage the variation points and integrate with the engineering tools mentioned above. “Gears” from BigLever and “pure::variants” from Pure Systems are good examples of such tools.
Design News: Why will one-off, product-centric development disappear? What will replace it?
Charles Kruger: Studies have shown that PLE techniques will remove up to two-thirds (2/3) of the engineering effort in an organization. By effort, I mean things like branching, merging, and all similarly tedious work that engineers hate and provides no value to an organization. Moreover, most organizations we come across build multiple flavors of all of their systems and products. Nobody builds just one and says that good enough. This supports the trend towards elimination of engineers focused on a single product-centric line.
William Bolander: One-off products will not disappear, but if you are developing similar systems in mass production, (e.g. trains, planes, automobiles) then you will want to consider PLE due to the cost and quality advantages.
Design News: But engineering organizations have been building product families for decades in the automotive, semiconductor mobile phone and other spaces. What is different now?
Charles Kruger (12:03): That’s correct. People have learned a long time ago that you can use expertise to produce things that are slightly different from things you've done before. What is different now is the level of efficiency. Product line engineering brings a doubling and tripling of efficiency. The systems engineering INCOSE website provides more details on the types and levels of efficiency in their PLE Primer.
Design News: How will PLE effect the digital twin – or will it?
Charles Kruger: The V-Diagram lifecycle highlights the process of conceptual design all the way through product release. What is sometimes lost is the fact that we need to manufacture the product, sell it, maintain it, etc. Now, to produce a digital twin, I need to understand the distinguishing characteristics for each and every variation in a family of products, to specifically understand the features that uniquely characterize each of my products while I'm engineering it. Then I’ll be able to fully realize the digital twin.
Design News: Some claim that PLE will help us achieve a zero-defects culture. I heard that claim before. How will PLE achieve what no other approach has ever achieved?
Charles Kruger: You’re right, zero-defects would be asymptotic. You’ll never get to zero, but we're always aiming in that direction. What we find in organizations that do a really good job of tracking and measuring their defects and their change requests is that their total number of defects across a portfolio can drop by 80 or 90% compared to the product centric approach. And it does make sense. For example, if I have hundreds of different products in my portfolio built on a common set of designs, then if I fix a defect once for any product, all the others get fixed for free because they're sharing the same content. PLE also helps to eliminate all the mistakes made when people try to manually branch from and merge back to a product-centric design.
|Image Source: BigLever|
John Blyler is a Design News senior editor, covering the electronics and advanced manufacturing spaces. With a BS in Engineering Physics and an MS in Electrical Engineering, he has years of hardware-software-network systems experience as an editor and engineer within the advanced manufacturing, IoT and semiconductor industries. John has co-authored books related to system engineering and electronics for IEEE, Wiley, and Elsevier.