The Product Development Process - Step 4 - Design

This is a series of short articles as an overview and a simple guide, for how new products come to market.This article is Step 4, the Design Engineering forThe Product Development Process.

Step 4  -  Design Engineering

The Design
Phase

True design engineering is science and art!(官方)下载analysis and synthesis.  It is compromise in the balance of conflicting constraints.  It is drawing on, and improving upon previous knowledge for solutions - in new challenges, or new solutions to previous concerns.

(官方)下载At Synthesis, our goal is to find theElegant Solution- not just any solution.  It is our objective to find the best blend of compromise in all theconflicting constraints.

In development, theDesign Phasehas 2 main components (and often a third):

1. Conceptual Design- (the macro level) where fundamental and sweeping ideas are considered, evaluated, and put together to achieve the product goals;
2. Principle Design or Characterization- (the micro level) where the details are composed;
3. Oft timesProof of Principlephase(s) are intertwined with the design engineering to assure a complete and secure final product deployment.

Discussion on each phase is in the sections below.Click the links for direct access.

Iteration in Design Engineering

Design phase is just one of the iterative steps in complete product development.Referring back to the map in theProcess Overview(Step 1), the design phases often require iteration withPrototypes(step 5) and with Testing.

The process of Design to Prototype to Testing and back again is one of learning, usually with new inputs like customer acceptance, or manufacturing feasibility.It is part of understanding and perfecting the product so it will succeed in the market.How many iterations?That depends on the amount of learning and the final objectives.

Either way, the design engineering phases are the best effort at perfection, with prototyping and testing as verification and acceptance.

Conceptual Design

This is the big picture.  Finding the best overall design always starts by considering various possibilities.A more complex problem deserves more concepts to consider.Start, with something like a brainstorming session, and measure all kinds of ideas.A reasonable list ofrequirementsat this point is extremely valuable for assessment.

Side Note:There are many methods for collecting ideas, like Brainstorming orSprints, and each has beneficial attributes.These alone do not constitute conceptual design, because there is no substitute for quiet, individual contemplation.Activities like Brainstorming can stimulate ideas and thinking in different directions, but they should be used to enhance and accelerate the design processes, not short-cut them.

The conceptual phase is a time for sketching on the whiteboard or on paper.  It is a time for bringing good brains together, and a time for discussion.Also, it is a time for quiet contemplation where the group ideas are carefully thought through.  Capture ideas, the evaluate, mutate, blend and reincarnate them, because design engineering is a process of sorting through possibilities.

It is my firm belief that the best ideas come from multiple good sources.By bouncing ideas back and forth, mutating them through the filter of various perspectives, the elegant solution rises to the surface.

"There is no smartest person ...The best ideas come from synergy of multiple sources."

Evaluating Concepts

There are always many ideas to sort through.Some stand out immediately.Other ideas are good, but conflict with each other.Here are some things to consider while evaluating and choosing which ideas are best:

• Analyze concepts for adherence to goals and requirements.  (This is one reason you need theEngineering Specificationof the previous step.)
• Determine areas of improvement over the competition.
• Find areas of technical stretch (if any) for each new concept.
• Does the concept require a new invention to make it work?
  • Is there technology available to accomplish all the tasks?
  • How can aProof of Principle (PoP)assure that areas of technical stretch won't delay launch?
  • Are there substitute technologies to use if a new technology does not make it?
• Examine impact on time and cost goals for each new idea.
• Think like your customer, or ask your potential customer(s), then use their input as part of your decisions.

In many cases, technical innovation makes the task or project possible.  For areas of technical stretch, it is important to prove concepts in advance with aPoP(Proof of Principle) demonstration.  A careful evaluation can help see if the innovation will fit within time and/or cost constraints.Separating these areas of technical stretch into their own mini-projects (as a parallel path) can keep the main project rolling.  We call these design engineering mini projects PoP's.  (See belowfor more discussion on PoP's.)

Design Engineering Competitive Analysis

The conceptual design phase is also a time for comparing competitive products against your list of requirements.Use the comparison to see how your ideas are similar, and to see how your requirements drive the new product to improve on what exists.

I have seen this process short-cut many times with a blind ambition that the new ideas are superior.  This can lead to missing the most obvious things that potential customers already like, meaning it will be harder to gain acceptance in the market.

Principle Design or Characterization

This is the stage of hard-core design engineering.Now, the computer comes in very handy - both for CAD and for design analysis.  This is when fundamental design engineering takes center stage, and the prior work of the Engineering Specification is the focus.

Typically this stage of the design includes work in all the areas of the project - perhaps by several individuals or teams depending on size and complexity.  The routine generally includes individual work as well as design review meetings at appropriate intervals.

Design review meetings typically consist of:

• Design analysis reporting for adherence to the requirements (step 2).
• Coordination and Resolution of issues - especially those crossing between teams.
• Discussions about the incorporation of new knowledge and/or technology.
• Review of DFM, Design For Manufacturing feasibility, and other manufacturing questions.
• Reporting of progress with respect to timing.

The principle design stage should also include optimization where areas of the design may iterate in getting to the elegant solution - one of the ways a product transforms from good toGREAT.

Proof of Principle - or - PoP

When conceptual design includes something technologically new, it creates a special condition.In many cases, it is not a completely new concept, but something new as part of the product.It is these new, or inventive areas that make a product exciting, but they are also areas that can bog down development.We reference these asPoP, because we mustProve thePrinciple before it can go to market.

We sometimes call these areas of innovation - "Technical Stretch" - that require Proof of the Principle.

So, prior to inclusion with the main design, areas of technical stretch get separate treatment.This may include prototypes ahead of time to determine if certain subsets of the technology will function to accomplish the goal.

For areas where current technology or a precedent does not exist, it must be invented.  These areas must be identified early, then worked in parallel to see if they pan out.  The main design engineering will usually have a back-up or "safe" plan to implement if the invention does not pan out.  If, or when, the idea is proven or determined as safe for the prime design, it is incorporated.

This a development phase of product design engineering often requires invention or optimization using tools likeStatistical Design of Experiments.  Testing can be a big part of defining and achieving a technical stretch goal.

Proof of Principle Example 1:

A special lightweight part was needed for a support in a machine design.However, there was a conflict with the weight and strength requirements.  To address the need a special version (lightweight) was conceived.  The lightweight version was made with powdered metal sintered around a machined part.  The powdered metal provides the shape and density desirable for weight, while the machined part provides the necessary strength and contact properties.

Though the concept seemed sound, at that time, a mixed material part as proposed had never been done.  Could the process be reliable?Would it be safe?

To assure the component experiment does not delay product launch, a cast part (heavier, and more expensive) is a back-up if the new process did not work.A lot of effort went into the design engineering of the lightweight part, in parallel to the rest of the work.  Once it proved, the lightweight design replaced the casting.

This is an example of using the PoP process to achieve desired goals without risking an entire product launch.  Usually it satisfies the bosses that launch will be on time.  Often, great things come in small ways.

Proof of Principle Example 2:

For one client, our job was simply to find the right combination of material, size, plating (if required) and geometry to accomplish a task.  The function was extremely critical, so literally thousands of tests were conducted in a Design of Experiments fashion to find, and statistically verify a workable design.  Tests included environmental chamber testing, pull testing, and many others.  It also required the invention of a process to make the parts to fill the desired outcome.

We incorporate both design engineering and manufacturing process engineering.After many design and process attempts, the work finally concluded with a robust design combined with a proprietary process to satisfy the need and exceeded the given requirements.

This example illustrates how the proof for an inventive design came with not only with the invention, but it required the second invention of a process to implement it.

Concluding Thoughts About Design Engineering ...

The design phase of product development includes several sub-steps that are usually iterative.  First designs and first prototypes usually show opportunities for improvement, then additional design cycles hone the product.  Especially for new technology, time for learning pays big dividends.  Design engineering refinement in this way yields the best possible products.

Next Up:Step 5  -  The Purpose of Prototypes