thumbnail of Sylvia Wu
Test, Usability & Certification

Strategic Testing Methods for Early Stage Hardware Development

Good products are developed with an iterative process (James Dyson famously made 5127 failed prototypes before he delivered a working Cyclone bagless vacuum).

But while an iterative process is the most successful hardware development strategy, prototyping hardware can be expensive and time-consuming. So to get the most value out of each prototype, you need to aggressively test where a product falls short with every iteration.

In this article I’m going to outline strategic testing methods for early stage hardware development across three key categories:

  1. Usability testing
  2. Material and finish testing
  3. Key component testing

Across all three of these categories, it’s important to keep in mind the most effective testing strategy is to evaluate individual components rather than the whole system at once. This strategy will help you build both a comprehensive test plan and move as quickly as possible while making the most of your resources.

With a clearly defined testing strategy in each of these categories, you’ll be able to iteratively improve your designs and ultimately build an excellent working prototype to inform the next stages of development.

Usability Testing

When you set out to design a product, you’re establishing a hypothesis that says, this new thing will solve this specific pain point for these target users. To help refine, and hopefully verify, that hypothesis, you need experiments.

Usability testing is essentially a series of experiments that allow you to better understand how target users experience your product to ultimately verify or falsify your hypothesis.

Without comprehensive usability testing, the product features you build won’t be verified as useful by your target users, so you might end up with a product no one likes or understands! And unlike with software, after a hardware product ships you may never get a second chance to get it right.

I learned this lesson the hard way: I once helped design a wearable product with volume buttons on its side. The product had no specific orientation during use, so unlike the volume buttons on the side of a mobile phone, it was hard to distinguish the volume up button from the volume down button.

So I put raised “+” and “-” markings on the buttons and called it a day!

After the product shipped, some customers complained they couldn’t tell the volume up and down buttons apart when wearing the product; it turned out the raised markings were visible, but too subtle for tactile feel.

This could have been easily fixed had I caught the problem during product design by doing more usability testing.

So make sure you plan for usability testing. But how exactly do you design successful usability tests? From my experience, here are 3 most important things to remember:

1. Target Specific Feedback

Ask your focus groups specific rather than general questions to yield more educative answers.

2. Leverage Partial Prototypes

Partial prototypes are great for getting feedback on a specific functionality or interaction.

For example, if you’re designing a bike light, you can test how the light attaches to the bike as an independent module. If you want to see how users interact with each attachment method, you only have to prototype the attachment mechanism rather than the whole system, saving you a lot of time and money.

3. Keep it Unrefined

There’s no need to build super refined prototypes for most usability tests. The lack of high fidelity color, material, and finish can actually be beneficial: it forces the focus group to concentrate on the form of the product. Form helps to convey how something might be used, and you need to confirm that your design provides affordance effectively to the user.

 

With an iterative approach to usability testing (test early and often), you'll have an excellent perspective on how real users experience your product.

Testing Material and Finish

Aesthetics greatly impact the perceived value and quality of a hardware product. A product that looks good despite use and abuse will surely delight its users, who will turn into loyal ambassadors (and repeat customers) for your company.

If you’re developing a wearable product, material testing is a high priority for you. For example, nickel allergy is very common, so if you’re sourcing an off-the-shelf buckle on your wristband product, it may be prudent to get a nickel testing kit to evaluate samples.

The best way to assess the durability of materials and paints is to test them against common household chemicals. Unless it’s a luxury product, users will most likely clean it with household chemicals like Windex, Clorox, and isopropyl alcohol.

And it’s not just cleaning chemicals you need to be aware of—lotions and sunscreen can cause many types of plastics to degrade and these cosmetic products come into contact with handheld products accidentally but frequently.

Also be aware that not all material requirements will be found on a data sheet, so you may need to build custom tests. For example, I once worked at a medical device company making biopsy equipment, where we tested a number of material and paint options for their resistance to staining by blood.

This particular material property isn’t found on data sheets, so we had to become friends with, well, the local butcher and gather our own data.

Your product may have similarly unique material requirements that warrants custom tests to evaluate options in real use case scenarios.

Testing Key Components

All products have components vital to its functionality and usability and these vital components require extra scrutiny in the early development stage.

For example, a fragile buckle on a bicycle helmet will soon render the entire product useless, so you should invest significant resources to ensure the buckle meets your product requirements.

When testing these key components, it’s important to simulate conditions that will be as close to real use conditions as possible.

For example, if you’re testing the life of a plug connector, building an automated fixture that inserts the plug connector into the receptacle the exact same way every time doesn’t simulate a real use case; a human will insert the plug with slightly different orientations every time, and that may cause a very different amount of wear on the component.

Make sure that your test fixtures simulate real world use cases, with varied and imperfect use and conduct enough tests that you can be sure your key components are sufficiently robust.

Main Takeaways

A good product is greater than the sum of its parts, but a flawed product is no better than its worst component.

Testing during the early stages of product development should be focused on evaluating individual parts of a product rather than the whole system, and remember that low-fidelity prototypes will allow for more iterations on the same budget compared with high-fidelity ones.

A comprehensive testing plan that covers usability testing, material and finish testing, and key component testing will empower you with the feedback you need to bring a product to market that provides true value.

Was this article helpful? Help us by sharing
Last page
Hardware Testing 101
Software and hardware engineers alike have heard some form of this advice: “Build lots of prototypes; iterate as fast as you can.”
Up Next
Pre-Production Hardware Testing Methods
The pre-production phase of the hardware product development cycle encompasses the commonly mentioned EVT (Engineering Verification Test), DVT (Design