As is so often the case, when Curtis Ray’s wife told him that he snored, he didn’t believe it.

Once Curtis recorded himself, however, and confirmed that he was, in fact, one of the approximately 40 percent of adult men who snore, he set out to find a way to address the nighttime noise.

It took two and a half years, 60 prototypes, and even some of his children’s craft foam, but the former designer and sensor pro found his best snore-stopper yet: an invention of his own called the Hupnos Sleep Mask .

One way to treat snoring caused by sleep apnea  is CPAP, or continuous positive airway pressure. CPAP machines, designed in the early 1980s, use a hose and mask to deliver gentle, continuous air through one’s airway.

Ray’s sleep mask relies on a slightly different letter: EPAP, or Expiratory Positive Airway Pressure.

There are several EPAP products on the market that are designed to help you stop snoring. EPAP tape, worn over the nose, for example, contains microvalves that allow the wearer to breathe in freely. When the snorer exhales, the valves close, generating extra air pressure. The act of exhaling traps the air – increasing the pressure, dilating your airways, and, most importantly, reducing the snoring.

Curtis wanted to take the principles of EPAP and bring them to a familiar bedtime accessory.

In late 2016, Ray began early iterations of what would ultimately become the Hupnos Sleep Mask. The invention, as it exists today, looks like a regular eye mask, except it features an EPAP cushion, just below the nose, to control exhalation pressure. The mask is also equipped with an accelerometer, a microprocessor, a Bluetooth connection, a valve, and a vibration motor.

With the Hupnos technology, snoring patterns are recorded using the sleeper’s phone microphone. Additionally, the mask’s accelerometers track a person’s movement and position.

If the mask recognizes snoring and detects that you’re in a position where you’re more likely to snore – say, on your back and not on your side – the mask’s vibrating motor can give you a cue to roll over.

And in the morning, in a phone app, results will show percentage of time spent snoring.

“Once you're done sleeping you can look at the data, your positions, and your snoring level and snoring percentage,” Ray told Tech Briefs. “I can look at the entire night and get an idea of what the sleep quality was.”

Curtis’s dream of creating a sleep-tech product didn’t happen on the first try, of course. There is inevitable trial and error, after all, when you’re trying to put accelerometers and motors on someone’s face while they’re trying to sleep.

Ray, founder and CEO of Hupnos, spoke with Tech Briefs about the many attempts – and why he considers all 60 of his product iterations to be a necessary part of the manufacturing and prototyping experience.

Tech Briefs: What inspired you to create the Hupnos Sleep Mask?

Curtis Ray: About three years ago, my wife started complaining that I was snoring and of course, like everybody, I didn't believe her in the beginning. So, I recorded myself at night and found out, “Oh I really do snore.” I snore pretty loudly.

And so, I started looking at what products were out there that were available to stop snoring, I tried everything and didn't really like what I found. The closest that I found was EPAP tape, which was difficult to use, but it worked. It was difficult because it's hard to go to sleep with it on your nose.

So, I developed a system that looks like an eye mask, but when you fall asleep, when you snore, it will apply EPAP therapy.

Tech Briefs: What was the very attempt to make the device?

Curtis Ray: I said, “You know I don't like any of these. I'm going to do something myself.” And I was sitting with my wife and I said, “I'll bet that I could try tonight.”

And I did.

I grabbed my kids' art boxes and threw together a little mask made out of craft foam and had a one-way valve on it and put it on my face and slept with it.

Tech Briefs: How well did it work?

Curtis Ray: So that was sort of first generation, but within the next day I was able to say, “Did that help me or not?” And, yes, it was uncomfortable, but it did reduce my snoring. That one little step then become another step, and within a few days, you're making another prototype and each time you do it, the prototypes become a little bit better.

Tech Briefs: What did your early devices look like?

Curtis Ray: Our first devices were simply based on a timer. After twenty minutes we'd assume you were asleep, and the exhalation pressure would start to increase. We found that that wasn't good enough. What made more sense was to actually detect whether somebody is asleep and snoring, and that's when we developed the app to monitor your movements and to listen to your snoring.

Tech Briefs: What were your challenges, if there were any, in the product development phase?

Curtis Ray: Oh boy. From an engineering perspective, this was a very challenging project, because people are very sensitive when they're going to sleep. You have to get everything right from the point of view of how big it is, how heavy it is, or any particular shape.

And the little things – like what kind of materials you're using and how flexible it is, how soft it is, the idea of making a mask that you can roll over on your side without it coming off, and yet have it soft enough so that it doesn't feel like anything but an eye mask. Those challenges were immense.

Tech Briefs: How many prototypes did you make?

Curtis Ray: The whole concept of fast prototyping is now available to us, and we took advantage of that. We did 60 different iterations over the two and a half years. It was critical for just getting the right fit for people to feel comfortable with us.

Tech Briefs: Did you use 3D printers for the prototyping?

Curtis Ray: We used 3D printers for the initial plastic work, and then we actually used the 3D printers in order to make molds for the silicone. We were able to cast medical-grade silicone into 3D-printed molds for prototyping and that saved a lot of effort because you could turn that around in a couple days and you'd have people sleeping with a different type of silicone piece.

A look at early Hupnos prototypes. The masks (at left) are revisions #50 (thermoformed and sewn), #35 (molded over 3D-printed parts), and #20 (3D-printed), from top to bottom. The bottom-right 3D-printed part resembles what Hupnos injection-molds currently. The two center-right parts are 3D-printed molds for the silicone prototypes, and the upper-right part is silicone-molded from the 3D-printed tooling. (Image Credit: Hupnos)

Tech Briefs: What was your process for validating the device design?

Curtis Ray: Find people that are easy to reach and comfortable to talk with – and have them on your tests. Once you've got your problem nailed, then find people that have that problem and are interested in solving the problem and then make sure that they're happy with the solution – that it's effective for them. If it’s not effective, find out why and iterate until you've taken care of all the issues that they've come up with.

Tech Briefs: What advice would you have for a design engineer trying to make a product?

Curtis Ray: We're at a 12-month cycle now for a production device upgrade. But for the initial ones, start as small as you can. Do something in a day, and then do something in a couple days. Get things done in very small steps rather than working on the grand plan that might take you six months before you get to test anything. Start the small tests early.

What do you think? Do you have any prototyping advice? Share your comments and questions below.