DFx: Designing for Success

What is DFx? DFx is an acronym used often in reference to concepts or guidelines involving design for manufacturability, test, and production readiness. In the world of innovative and complex medical devices, DFx can be an invaluable tool for meeting business objectives by ensuring an emphasis during development on successfully achieving long-term product and program goals.

Fig. 1 – Software and hardware engineers team up to solve a tough technical issue.

DFx is sometimes referred to as “Design for Excellence,” an arguably compelling but somewhat vague description. In practice, DFx is best understood as “Design for Success”—designing a product to meet overall product and business objectives that are measures of success and excellence.

Effectively implemented, a DFx approach will:

proactively address long-term product and program requirements;
improve financial performance by managing overall product lifecycle costs;
mitigate production risks during development; and
position and equip teams to address current and future product and program issues effectively.

Planning for DFx Success

There is no substitute for experience in DFx, and well-tenured, cross-functional contributors during device development are invaluable. Involving multiple disciplines throughout the development process provides broad coverage of product and program goals and issues, promoting complete “big picture” solutions.

At the same time, it is important to recognize that diversity and experience within a team can add complexity to project communications and management. With an eye toward DFx, it is important to establish, maintain, and continually communicate clear expectations and responsibilities for project teams. Documented DFx goals and requirements for both the product (e.g., unit cost, MTBF, test methodologies, etc.) and the program (development cost and schedule constraints, key milestones, scale-up plan, etc.) provide a map and compass for the team throughout the program to use when navigating through barriers, opportunities, and critical decisions. Many teams utilize traditional project management tools, including project charters and responsibility matrices to develop, track, and maintain useful summaries of expectations and responsibilities. (See Figure 1)

Implementing DFx

Fig. 2 – Team members consider DFx goals and requirements throughout the development cycle.

Good DFx practices and guidelines traditionally address manufacturability and test requirements but, for medical devices, should extend to address service, regulatory, sourcing, reliability, usability, total lifecycle cost, as well as market objectives. Effective DFx implementation relies on team members from all functional groups to consider DFx goals and requirements in each phase of the development cycle, from planning and requirements development through product validation. While DFx, like all good design practices, relies on the skill and experience of team members, there are techniques and mechanisms that can equip teams for success, including the following practices. (See Figure 2)

Inject DFx into the development process—build DFx activities into development plans and standard operating procedures.
Document DFx checklists for functional areas (manufacturing, test, software, procurement, electronics, etc.) that represent best practices.
Establish and engage a cross-functional team from the start of design.
Leverage the experience and expertise of team members from all functional areas, nurture teamwork and mutual respect.
Review designs early and often, and require DFx objectives as criteria for all project and tech reviews.
Develop and execute to an intentional scale-up plan with milestones, as understanding production volume targets helps the DFx process and is key to effective design transfer.
Implement a means for regularly communicating/ reiterating product and program success criteria.

Summary

In review, while the concept of DFx has evolved to include a broad range of engineering and process activities, the ability to design for successful execution of product, project, and business objectives is more critical than ever in a medical device market with increasing expectations on quality and overall cost. Effective DFx practices rely on a solid understanding of big-picture goals, intentional DFx planning and disciplined design execution, and effective leveraging of diverse and experienced people throughout an organization.

This article was written by Dirk Smith, Chief Technical Officer and Chief Human Resources Officer, Minnetronix, Inc., St. Paul, MN. For more information, Click Here .