Technical
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NPI in Seven Steps – Design Verification Run

Design Verification is part five of our New Product Introduction series. If you missed the previous posts and want to get caught up, start with the introduction post.

Your team has now received the Engineering Verification units and your manufacturer has completed their test plan to ensure they are building the product correctly. You’re now ready to build millions, right?

Now quite. You have a nice prototype that may even look like a product, but you and your manufacturer need to go through a few more steps before reaching full production, well at least if you want to get it right.

NPI Design Verification build

At this stage of the New Product Introduction, we are going to build what is called the Design Verification build, or just DV. After completing the EV run, your team and your manufacturer probably had a few design changes needed to get the product working right and able to test efficiently. If those changes were significant, you might have had to redo the EV build, but otherwise, the changes get implemented and the DV build gets kicked off.

This will still be a relatively small run, maybe twice the size of the EV, but still less than a hundred units or so. The difference is that the design will be as close to the finished product as possible. This includes enclosures, PCBs, and any other user interfaces. But not necessarily labels and packaging.

The point of the DV run is to ensure that any changes made during the EV build were implemented correctly and that the ICT, optical, and/or the FCT are ready to go. As we’ll see below, there are a few additional tests that you are able to complete with these units.

Run the Process

For the manufacturer, the Design Verification build is a very hands-on run. They are spending as much time documenting and rehearsing each step of the process as they are building the product. They do this as an investment in making sure that everything will go smoothly when they start full production.

The build process that the manufacturer is creating is like a recipe that they will use when they start to crank out units in the thousands. The better they can refine the recipe now, the smoother it will be when they start production as it’s easier to work out the bugs now.

Refine the Design

For your team, this build will allow any refinements in the design to be tested and the marketing team can see what the final package will look like (the pretties are very important to them). This is a step past the EV units as it would include the first tooled enclosures (may only use ‘soft tooling‘) and the size and features meet what the end product will be.

As I talked about in the Fail Fast post, seeing and holding a product make it real to people so this build provides that ‘real feel’ experience. This is important as minor bumps in the plastic can be felt but not seen in a CAD program. Seeing how bright the LEDs are or how loud the speaker is may drive additional changes now that it is in the plastic housing.

Certification Testing

For many certifications, you are required to provide a product sample that is in the final housing. As the DV build is the first build that would include this feature, it is often the build that is used for any certifications your device needs.

For any product sold in the US, this would include FCC or the CE mark for the EU. These certificates can take weeks to complete the test, write the reports, and wait for the governing body to provide the stamp of approval. This long delay is why the DV (rather than later builds) are used.

Testing may also be done that isn’t necessarily a certification requirement but more for product durability. This could include:

  1. Drop and vibration testing (make sure nothing breaks off)
  2. HALT/HAS (attempt to accelerate component life)
  3. Environmental (does it mold or melt)
  4. ESD tolerance (does it survive a simple static shock)

Some of these tests you may have started with the EV build, but may need to get repeated with the new design (and extra units that have arrived).

Could you Just Skip the Design Verification?

Let’s say that your EV run was perfect, no changes were needed and the manufacturer has a fully working FCT in place. Do you need a Design Verification run?

The answer, like so many in life, is that it depends on your level of risk tolerance. The DV build gives your team and the manufacturer another low-unit run to make sure everything is ready to go before making huge commitments. Each build will become larger (and thus more costly) and if bugs are found in the hardware or pre-installed firmware, it’s that many more that will need re-work or be scrapped.

As the above graph shows, the further you go, the higher the cost of creating changes will be. These costs are both monetary (you might need to change fixtures, change plastics, or buy new parts) but also in time to build new items.

So if the team is in a rush to get to production and the EV build was a success, then the risk vs. reward of skipping the DV may be low. On the other hand, if money is tight or new features are being added or changed, the DV may be the best option to wring them out.

Design Verification End Result

At the end of the Design Verification build, your team will have on hand a large number of almost-product-ready units. Units that can be shared more broadly within the company as it is starting to look ‘nice,’ as well as with key business partnerships.

It’s not just about the pretty factor, the DV build also helps your manufacturer get ready for production. When they have completed the build they should be able to provide a more accurate price quote for their overhead and output ability. Usually, this trends in the positive direction for your company as most manufacturers tend to buffer the estimate, but if it turns out your product is more complicated than originally thought (or feature creep) they may work with you to adjust the design or accept a higher cost.

With a successful DV run behind you, both your team and the manufacturer can start to gear up for product release and full-scale production. But standing between you is one more build: the Product Verification build which we will talk about next.