IPD and MDO
A key cultural change introduced into many U.S. industrial sectors toward the end of the twentieth century was the integrated product development (IPD) process, which dramatically improved the execution and efficiency of the product development cycle. IPD is also known as “simultaneous engineering,” “concurrent engineering,” or ”collaborative product development.” Its central component is the integrated product development team (IPDT), a group of stakeholders who are given ownership of and responsibility for the product being developed. In an effective IPDT, all members share a definition of success and contribute to that success in different ways. For example, systems engineers are responsible for the big picture. They initially identify development parameters such as specifications, schedule, and resources. During the design process, they ensure integration between tools, between system components, and between design groups. They are also responsible for propagating data throughout the team. Design engineers have responsibilities specific to their capabilities and disciplines. Typically, design engineers determine the scope and approach of analysis, testing, and modeling. They define the computational tools and experiments required to support the development of a design and its validation. Manufacturing engineers ensure that the components can be made with the selected manufacturing process, often defining the computational simulation tools that are required. Materials engineers provide insights into the capabilities and limitations of the selected materials and support development of the manufacturing process.
IPDTs can range in scale from small and focused to multilevel and complex. Regardless of size, however, the defining characteristic of an IPDT is interdependence. The key to a successful IPDT is that the team members, and the tools they use, do not work in isolation but are integrated throughout the design process. This approach may entail communicating outside the original company, country, or discipline.
Owing to the demonstrated success of the IPD process, many engineering organizations, particularly at large companies, have invested considerable human and capital resources to establish a work-flow plan for their engineering practices and product development cycles as executed by the IPDT.
The capability and dynamics of the IPD process are illustrated by the execution of a computationally based multidisciplinary design optimization (MDO). Modern engineering is a process of managing complexity, and MDO is an important computational tool that helps the systems analysts to do that. For example, a modern gas turbine engine has 80,000 separate parts and 5,000 separate part numbers,1 including 200 major components requiring three-dimensional computer-aided engineering (CAE) analysis with structural finite element and computational fluid dynamics codes. This CAE analysis can easily require over 400 person-years of analytical design and computer-aided design (CAD) support. The only rational way to accomplish this engineering feat organizationally is by means of an IPDT. Owing to the development and validation of computational engineering analysis tools such as finite-element analysis, computer-based MDO has become routine for many systems or subsystems to improve efficiency and arrive at an optimized design or process. Computer-based MDO automates work flow, automates model building and execution, and automates design exploration. A block diagram of the relevant analytical tools utilized by MDO is shown in Figure 2-1-1.