For the last few weeks, NASA engineer Mike Buttigieg has been going back and forth to Antelope Valley Hospital in Lancaster, California — and sometimes, on the way back, he'll head to the hardware store.
Buttigieg, along with a team at NASA's Armstrong Flight Research Center, has been working on an oxygen helmet that emergency-room physicians can use to treat COVID-19 patients — an effort that requires design conversations with hospital professionals and the occasional quick-trip to a supply store for small parts.
The oxygen hood, begun by Buttigieg in his own garage, is meant to be used on patients exhibiting mild COVID-19 symptoms and breathing troubles, freeing up ventilators for those in greater need.
The helmet functions like a continuous positive airway pressure (CPAP) machine, which forces oxygen into a patient’s low-functioning lungs.
The oxygen hood, worn securely over the head, has an inlet and exhaust port allowing airflow into and out of the helmet. A magnetic strip creates a window-like port so that medical staff can get access to the patient without removing the hood.
A rubber diaphragm, attached to the plastic ring at the base of the unit, stretches over the patient's head and then forms a seal around their neck — perhaps the most difficult aspect of the design process.
"Getting the size and shape of this right was tricky as every patient’s neck is a little different in size," Buttigieg told Tech Briefs.
The Helmet: From Idea to Prototype
With the help of a NASA colleague and fellow engineer, Buttigieg built the the first helmet prototype in his garage on March 30th.
The next day, Buttigieg went to the Antelope Valley Hospital to test the hood on a continuous positive airway pressure (CPAP) machine. After noting the changes needed – new outlet locations, hood sizes, door dimensions, and neck holes – he ordered materials for 50 hoods and made the second prototype that same week.
The oxygen hood went through modifications, as the Armstrong engineer would stop at the hospital and bring early prototypes to doctors for review.
"From there, I would figure out what changes may need to be made, sometimes consulting with other members of the [Antelope Valley] task force, try to find the right parts to improve the design, and then modify the helmet as necessary," said Buttigieg.
Buttigieg was working quickly, with the understanding that a thousand or more helmets could be needed in just a few weeks, given how cities at the time had been experiencing exponential growth of coronavirus. Building that many units would also require additional production help from businesses and the local community.
Between the second prototype and the race to make hundreds of helmets, Buttigieg has gone to the hospital – or had doctors come to his garage – at least eight times.
The communication continues today, as the hoods are tested in the Antelope Valley Hospital. The majority of the changes turned out not to be the parts themselves, but the assembly, according to the NASA engineer.
“Small nuances in these steps could make or break the integrity of the unit,” said Buttigieg.
Officially called the Aerospace Valley Positive Pressure Helmet , the device was successfully tested by doctors at California's Antelope Valley Hospital. The Spaceship Company (TSC), a Mojave, CA-based spacecraft manufacturer, began producing 500 helmets at the end of April, and a request was submitted April 22 to the FDA for an emergency use authorization.
Just yesterday, the 500 unit were built at TSC’s FAITH facility in Mojave.
In an edited interview below, Buttigieg tells Tech Briefs about how the oxygen helmet came to life and how engineers today can do their part to support the medical community.
Tech Briefs: What does this oxygen hood look like?
Mike Buttigieg: The helmets are somewhat basic, but the details are hard to get just right especially when you put all the parts together. There are several points of failure, and if not put together properly, the seals can fail and it would lose its effectiveness. We learned a lot through prototyping and test assembly runs.
The key elements include the clear vinyl hood element, that is attached to a plastic ring to hold it in place. There are two ports, an inlet and exhaust port that allows for the air flow into and out of the helmet. There is a magnetic strip that we used to create a port or a window-like area so the medical staff can get access to the patient without taking the hood off. A few straps have been attached to the base of the helmet to help hold it in place on the patient.
Tech Briefs: What was the most difficult component to get right?
Mike Buttigieg: The key part is the rubber diaphragm that is attached to the plastic ring at the base of the unit. This is the part that needs to be stretched over the patients head and then forms a seal around their neck. Getting the size and shape of this right was tricky as every patient’s neck is a little different in size.
Tech Briefs: What inspired this design? Was it based on a previous one, for a previous NASA application?
Mike Buttigieg: Some of the emergency room doctors we were talking to wanted to be prepared to handle large volumes of patients that may need greater oxygen supply, but not at a point where they need to be placed on a ventilator. They saw some images of these clear plastic hoods being used at other hospitals overseas and asked if we could help design and build something like that for their use. So, we did some research to see what was out there.
There are companies that commercially make hyperbaric devices similar to these, but given the high-demand for the units, availability is limited. So our challenge was to see if we could come up with an alternative made from easily sourced parts.
The inspiration for the design we went with actually came from an off-the-shelf cast protector unit. These devices, normally used to shield a cast from getting wet in the shower, are made up of the same fundamental elements of the device: a flexible diaphragm, a hood, and a frame/ring to join the two. Making minor changes and replacements to these parts enabled us to create the bones of our first designs.
Tech Briefs: How is the design approach of an oxygen helmet similar to (or different from) the kinds of technologies usually being designed at Armstrong?
Mike Buttigieg: At NASA Armstrong, a large part of our culture is innovation and design. We usually apply this to aircraft, trying to make them more efficient or testing new technologies. Sometimes the activity is minor, like a recent project I was involved in supporting the Solar Eclipse missions in 2017 . It seemed like a simple request: replace the window with a higher quality one so videographers and photographers could capture images of the eclipse from the air — because when you are flying above the clouds there is nothing to obstruct the view! We did this successfully, but it was an iterative process to review options, think about creative, careful engineering design, and ensure a quality fit that would pass the rigorous quality necessary to keep the aircraft certified. This same general process was applied to the helmets.
Tech Briefs: You’ve been busy, of course. What has been a typical day for you?
Mike Buttigieg: My main focus lately has been on the Aerospace Valley Positive Pressure Helmets.
Over the last few weeks, I have made a lot of trips to the local hospital to coordinate and get feedback on the helmet design from emergency room doctors, and other medical staff at the Antelope Valley Hospital. From there, I would figure out what changes may need to be made, sometimes consulting with other members of the task force, try to find the right parts to improve the design, and then modify the helmet as necessary. Sometimes the fix is easy, and I can use parts found in a hardware store. Other times the changes require more specialized parts like the vinyl hood part – that can take more time to get. We just submitted the design for an Emergency Use Authorization through the FDA, so I had to spend some time on the paperwork end as well.
The last few days, I have been spending most of my time coordinating and overseeing production of 500 of the pressure helmets. We are doing that assembly work at The Spaceship Company’s FAITH facility at Mojave Air and Space Port. We have a good team of about a dozen people helping with that. Lunch is usually on the run, just a lot of demands for my time. My days typically don’t end until later in the evening. It is exhausting, but it feels good that I can do something to help.
Tech Briefs: What can engineers and designers do to help the COVID-19 response?
Mike Buttigieg: It may seem simple, but I think the biggest thing is to not get sick! If we can keep the case-load down, then the medical community can provide a higher quality of care to the patients.
But from an engineering perspective, engaging with the local medical community and pay attention to some of the maker sites. There are a lot of products or designs of simple things that can be 3D printed from home to support the medical community. I know at NASA, there was a NASA@WORK challenge put out across the agency looking for ideas to help lend a hand and support the medical community. I think other professionals in the engineering community can do the same. I know for us at NASA, that is what we do: we solve problems.
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