“How long will it take to test those new samples?”
That’s a question design teams deal with regularly in product development. Testing is a crucial part of the verification process that proves your product will work as intended.
But many teams approach it wrong. They view testing as something to suffer through before releasing a design or making the next version, a necessary evil that slows progress. Worse yet, product schedules are often set up with the assumption that once the testing is complete, the team can move straight into building the next system.
Here’s the problem. This approach doesn’t fully factor in the reality that testing reveals issues. Issues that may take a long time to fix, likely more time than you allocated for.
Four Key Areas of Product Testing
What’s needed is a development schedule that not only accounts for possible testing failures but also promotes learning throughout the project.
Accomplishing this requires the team to be aligned in four areas:
- the test goals of each phase
- the priority of each test
- the risks to the project associated with each set of tests
- the need to hand-modify or rapid-prototype solutions when possible
Getting teams on the same page on these points is no small task. Fortunately, there are many tools and industry best practices to guide you.
- Define Your Goals Before Beginning
Understanding each verification phase’s goal is critical to crafting solid development timelines. When competing feedback is given to the design team after the evaluation of samples, it may cause confusion about what to change and what not to change. By making it clear to project teams what the verification goals are for each phase, and perhaps what the goals are not, the testing becomes focused on the most urgent priorities.
For example, if early samples were built to evaluate functionality and performance, testing for long-term reliability may be premature. Otherwise you may have to re-do your durability testing (often the longest portion of design testing) if you find a key feature to be missing or inadequate. If the goal is to pass all aspects of product requirements in a single round of design, this needs to be communicated well in advance. It’s better though to sequence the testing to follow the maturity of the design. Focusing on functionality, then performance, then durability avoids repeat testing and sequences the fastest and lowest cost testing first.
- Prioritize Testing with a Focus on Design Maturity
Testing priorities are often challenged by the number of samples, resources available, and even personalities within a project team. It’s not uncommon for the loudest voices to claim the first samples and largest shares of testing resources, even if a critical design aspect utilizes a technology the company hasn’t worked with before.
When this happens, the team needs to set egos aside (both attitudes of “don’t bother, my designs never fail” and “my work is the most critical to the project, it must be tested first”) and break down verification activities into a prioritized timeline.
Features with the lowest design maturity or familiarity must be evaluated first, along with characteristics that are the most difficult to simulate or calculate, like subjective human feedback. The team should also prioritize the testing that takes the longest to allow testing to be done in parallel, minimizing the overall time required.
- Don’t Overlook Project Risk
Project risk is perhaps the most overlooked aspect of planning a test phase. The project team must be honest about what happens when a key design aspect fails. Sometimes, mundane details of a design seem low-risk in isolation but reveal themselves as critical when we look back at how a failure impacts other teams or functions.
If a major component needs to be swapped out for an alternate because it can’t meet the design criteria, what does that do to the design of the enclosure? Or unit performance? Product cost? And, if the components for a minor feature need to be scaled up, how many other teams must modify their designs to accommodate it?
In addition, assuming you won’t have anything fail during testing creates a huge project risk that needs to be avoided. Be realistic about how quickly your team can implement design fixes found during testing, and make sure the time is allotted in the schedule. By studying potential project risks, teams can schedule tests to focus on the features that carry the most risk to the project, even if it is likely to pass.
- Rapid Adjustments Make for Faster Progress
Finally, design owners should be expected to hand-modify or rapid-prototype fixes whenever possible to test mitigation strategies more quickly. Rapid Prototyping is often used early in projects for concept development and sometimes used for flexible production techniques, but it is under-utilized in the design verification process. Since each stage of the project may require months to design, build, and test, teams should prioritize ensuring design fixes are effective rather than waiting for the next test phase. This has now become standard for software development as the tools allow for incredibly rapid iteration. However, for products that require physical assembly – often offsite – teams need to do what they can with parts on hand to evaluate solutions.
This means project managers must accommodate an additional week or two for quick-turn design fixes. In doing so, they can determine before the next design release if a fix was effective and avoid having to accommodate another design turn into the schedule.
Common examples of rapid prototyping may include:
- Cutting and rewiring traces on a PCB to pass EMC testing
- 3D printing scale models to check changes made in CAD
- Machining plastics instead of waiting for molded parts
In this way, identifying, training, and implementing these tools and approaches can help you achieve one of the most universally sought advantages over the competition – time to market.
Understanding EVT-DVT-PVT
One tried-and-true method for creating a development schedule is using industry-standard approaches for the build phases. Test teams often break projects into phases, like “Engineering Validation Testing,” “Design Validation Testing,” and “Product Validation Testing,” or EVT-DVT-PVT as shorthand.
In this approach, the phases are focused on three things:
- functional verification of small samples
- performance and quality verification of soft-tooled models in larger quantities
- the ability to produce a design at full line speeds with acceptable yields and quality.
Some projects may need only two of these phases, especially if they inherit mature designs with lots of re-use. Others may require an additional phase to advance the readiness of new technologies. And remember that these techniques apply not just to product design but to many different types projects where an iterative process is needed.
What’s critical here is to define the purpose of each major release and sample build at the start of the project, then provide adequate time after testing to implement a corrective action. There are tools available to make enhancing design verification easier. Some off-the-shelf options for enhancing design verification planning include DVP&Rs, Kanban boards, and FMEAs. These tools can incrementally improve project scheduling by identifying risk, balancing resources, and outlining projected timelines.
Put Your Plans in Moetion
If your product development team needs improvement, Moetion Technologies can provide tools and templates, onsite training or workshops, and strategic planning for design verification. We can also facilitate the completion of key documents for teams that have product expertise but are resource-constrained for project management efforts.
Connect today, and we’ll help you put your ideas in Moetion.
Until next time!
Ben Moes
Founder of Moetion Technologies