01/11/2021

The Verification & Validation Valley: Why Both are Critical in New Product Development

By Chris Stevens

Product life cycles are shrinking and disruptive technology is becoming the new norm. Speed to react to a shifting economy is creating a new set of standards for product and process development. All this leads us to a new set of challenges causing a re-evaluation of strategies for design and process verification and validation. This post will help you identify and minimise significant risks in your development process and accelerate your product to market.

orange plastic moulded part

Design vs. Process Verification & Validation (V&V)

First, I want to ensure we establish a baseline as this will be important as we unwrap this strategy later on. Let’s look at each a little closer.

  • Design. The specification and user requirements of a device and final assembly. Take a bike, for example, to help convey the design V&V, specifically the bike tire. The verification would be inspecting the diameter of the wheel while the validation would be determining if the wheel rolls when riding the bike. One provides statistics, while the other is more contextual because it asks, “How does the wheel work within the bike assembly?”

  • Process. How do the manufacturing inputs define the outputs. Using the same example as before, we can look at the manufacturing of a bike wheel. During manufacturing, verification means measuring a single bike wheel diameter while the validation is understanding the process inputs that determine the output of diameter over the course of a normal production run.

  • Process Development Strategy. Worthy of an honourable mention is robust process development as it makes up the core building blocks that provide the best chance for building a stable and capable process. For example, injection moulding uses the scientific moulding It’s the gold standard when it comes to developing a solid starting point.

Process Verification & Validation

These are the bookends to build objective evidence during the development process, but I believe there is an undervalued crucial middle point in that development process, a steppingstone toward full validation, called qualification. We can dive more deeply into that in a moment but first we need to establish some ground level understanding of validation. At its core, it can be broken down into one simple concept: understand the relationship between inputs and outputs. That seems simple enough but what makes it so difficult at times? One of the most debated concepts in various manufacturing operations as what should be included in the validation. This is what I believe to be one of the most fundamental challenges of the development process, or what I refer to as making the bridge crossing—the journey from making a few good parts to making many good parts.

This journey is often where risk affects the speed, cost, and quality requirements of the manufacturing process. More importantly, this step is the most likely spot for project derailment. It’s at this point that unforeseen challenges or setbacks happen in the pursuit of building objective evidence of process stability and capability. If not properly planned and executed that could mean the difference between first-to-market or trailing quarters behind the competition. But you can reduce this risk by using a qualification strategy.

3d printing machine

The Difference Between Qualification and Validation

Fundamentally, qualification is a simpler version of validation, and when coupled with sound process development it can be a rock-solid starting point for full validation activities. Qualification considers a single point within the process window at an increased sample size to determine if the process is capable. It’s sometimes called single-point validation. Although smaller than a full validation it packs a punch when delivering a high level of confidence for the main event. Still, it begs the question: Why not perform verification and validation back-to-back and skip qualification altogether?

First, prototyping and production are traditionally done at different locations. So, it goes without saying that waiting to perform validation until work is being done at the final manufacturing location makes sense. The second reason is a business strategy to reduce development costs until the final production development process. Validation is not required until just before commercial release. That’s a great reason to avoid the capital investment of process validation until after the product has proven it is capable of meeting user requirements.

No matter what, it all boils down to a single important question: What if validation fails? If normal process variation is larger than the designed tolerance, you’re setting yourself up for failure before even getting started. This is precisely where qualification becomes an integral part of the process—it helps drive up confidence in later success.

critical to quality
A sample critical-to-quality report provided to our injection moulding customers.

The Strategy for Fast, Effective, and Risk-appropriate Bridge Crossings 

While there is no one-size-fits-all strategy for every new product, there is one constant theme: Reduce risk while remaining fiscally responsible. Let’s fast forward to the stage between engineering validation testing (EVT) and the beginning of device validation testing (DVT). At this point, several builds and activities are taking place to start to lock in the design as the device moves into testing. Here, it’s important to consider leveraging the qualification approach so as to reduce the risk (and delays) of potential significant design changes before the design is fully frozen. Here’s how to do it.

In preparation for building DVT parts, include key quality documents that build confidence in critical features. Critical-to-Quality capability studies are great tools that add that extra layer of confidence and begin to lay out a pre-validation plan. Now with confidence boosted, risk reduced, and device testing underway proving device efficacy, you’re ready to springboard into validation. The path to full validation isn’t without risk, but at least knowing a single point inside that process window is capable can lower the project risk to a more manageable scale. Including this step also serves as a critical feedback loop for designers to verify if the design requirements are adequate for the design but also account for the natural process variation.

Then you reach the most monumental task: validation. It goes without saying that this is both a capital- and human-intensive process that is worthy of its own article explaining the multitude of different strategies, but let’s just hit the high points. As discussed earlier, the bridge from verification to validation is not without risk, but when you properly leverage a qualification strategy during the early builds it provides a great foundation leading to a full case of process capability. Unfortunately, there is no clear-cut perfect strategy for validation but it does remind me of one of the oldest lines about manufacturing: “You can pick any two among speed, cost, and quality.” I’d argue that this is no longer the case thanks to significant developments in digital manufacturing, but what is missing is consideration of risk. Risk has been a factor long understood but often never addressed head-on. I would argue that during validation efforts it should be front and center. If risk is not addressed or mitigated, it will continue to build as the project nears commercial release and could cause a full project restart. We’ve seen it far too often that the manufacture of a few good parts is not scalable and could have been avoided with a simple qualification strategy.  

Accelerating Your Next Program

The new norm for product development in a post-pandemic world has turned most traditional paths upside-down. Some will revert to historical norms, while others will be changed forever. Either way, what will change in the coming years is the importance of stepping back to look at the bigger picture and understand elements of a process where risk can mess with your project. We have been told for many years to balance speed, cost, and quality in manufacturing but I firmly believe that evaluating risk is equally worthy of attention. Using a smart risk mitigation strategy will help you innovate with confidence during your next project.