With the onset of COVID-19, many healthcare facilities around the world lacked essential personal protective equipment (PPE). This lack of supplies is putting medical professionals at risk and decreases the quality of patient care. Most available PPE is single-use which heavily strains the supply chain, especially with overseas manufacturers having products caught up in customs. This has caused a surge of untested and ineffective alternatives flooding the market, putting users at risk with a false sense of security and allowing respiratory particulate to contact individuals' faces. Seeing this need, our team decided that we would put our design skills, and 3D printing capabilities to use. We work so there no longer needs to be desperate pleas for proper PPE and sufficient supply. We never want to receive another call as we did from a Washington State hospital: a doctor lost to COVID, and the other on a ventilator because there was no PPE, and nowhere to get it. With COVID spreading rapidly through the US, we saw an opportunity to help both clinicians and our citizens. Our inspiration is simple: Nobody should be afraid to go out in public, or receive healthcare, because they don’t have the right protective gear.
What it does
The shield is fully sealed with hydrophobic, closed-cell foam that prevents the ingress of bodily fluids and ultra-small airborne particles, while still remaining comfortable for long periods of use (and yes we tested that extensively). It is durable, can easily be disinfected after use, is adjustable, and comfortable for users with different head shapes. We focused on choosing materials that would allow the design to flex and conform to any head it would encounter, yet is relatively inert so common disinfectants can kill viral or bacterial contaminants, without compromising or reacting with the materials at hand. The end result is a shield, designed to ANSI Z87.1 D3 specifications, with an easily exchangeable clear visor and head strap that has a price per use equivalent or lower than commercially available single-use face shields. To date, we have not found a product at a similar price offering a reusable design and offering a competitive price per use for disposable shields. These designs are up to the standards of healthcare facilities, yet are equally affordable and available for public use.
How I built it
There were many iterations, many concepts, and lots of hours printing to get to where we are today. In the truest fashion of iterative design, we would brainstorm, design, print, tweak, and run the whole process again. We scrounged materials for any place that had them while we narrowed our search for just the right combination. We optimized this reusable face shield for multiple manufacturing methods. We started with additive manufacturing, with a focus on FDM, and took special care to optimize the wall thickens to perfectly match nozzle widths so there is no more time wasted on filling in small dead spaces. For injection molding, we created a design that uses minimal material and the least necessary draft angle to drive the price per part as low as possible, and ensure good friction fit for the shield. Organically thought this process we came to use ribs to hold the shield in place, eliminating the need for costly and complicated assembly, yet easy to disinfect surfaces where fluid would not be able to well up and allow for viral and bacterial proliferation. The final icing on the cake was the decision to attached our head strap directly to the clear plastic shield, which allowed for easy flat packaging, further driving down the cost of getting the models in users' hands.
Challenges I ran into
There is an unforeseen challenge to innovating at a rapid pace with clinically relevant design in mind; how do you connect with experts who are willing to trial and provide feedback on devices, when they are busy enough fighting a pandemic? The short answer is you just keep making calls until you get in somewhere. Many an hour was spent on the phone collecting ideas, feedback, design constraints, and nice to have features for our devices. We wanted to focus on a design built to withstand a harsh clinical environment, satisfy stringent disinfection protocols, yet be cross-functional for clinical and daily use. With a limited budget, we needed a design to satisfy all users to keep our prospective tooling costs as low as possible. To that end, learning of the many different manufacturing technologies, their limits, and specific design constraints for each was mind-blowing. We can say with absolute certainty, we have learned more during this process than we ever expected to know about the product development cycle and in a very short time.
Accomplishments that I'm proud of
The team is particularly proud of how much we were able to learn and execute on this learning, in such a short time. We could not have done it without the help of this community, our mentors, and those who graciously fielded our cold calls to point us in the right direction. Our work partially reflects blood, sweat, and angry tears at SolidWorks, but to a larger extent the capacity of individuals to help each other in times of need. We can never claim to have mastered the product development/commercialization pipeline, but we have learned much more than we had ever thought possible through the support of the entire community. Our shield may not be a beacon of hope for the world at large, but it has made our group hopefully that we can help those in need through hard work and determination. Regardless of the outcome of our effort (beyond just the scope of the hackathon), we are proud to call ourselves a team and proud of the designs we have formulated.
What I learned
If we hadn’t fully appreciated it from our schooling, we now know: listening to the end-user and translating their concerns into a design is a very difficult process! We constantly found small hiccups or roadblocks, be it a limitation of the manufacturing technology or functionality limits, that we needed to design around. At the end of the day, we found how critical comfort and safety are to the end-user. A robust design that hurt after 3 hours was not an option. Conversely, something that could be worn for hours on end that was ultra-comfortable and lightweight might lack proper safety features. The symbiosis between these two factors would be critical for these designs to be adopted and effective. As we worked through this process these two factors bloomed into a tree of considerations we needed to make. Visual clarity is a must for long term adoption of the device, but thicker sheets of plastic, which tended to be less affected by optical aberrations from bending and manufacturing, are much more expensive to replace frequently. Never forget the issue of fogging and CO2 build up as well. It all came down to a simple constraint; when a shield is scratched it becomes hard to use and can greatly impact the quality of care.
There is much to be said about the design process and manufacturing technologies as well. So much so we will spare everyone the book we could write, but there is a short take away. Communication is key for the process and individuals involved to be successful. At every step of the process, information needs to flow between team members or you might find yourself with a design deviating from customer requirements, or a manufacturing firm quoting you thousands of dollars for a difficult to mold part. Silos will not enhance the speed of iteration and will complicate the path to success. We learned so much more about the process together, than we ever could have pieced together from individual efforts. Collaboration is key!
What's next for Med Dimensions - Reusable & Modular Face Shield
The group is actively perusing future commercialization efforts for these face shields. The group hopes to produce a small production run for validation of the design and further customer feedback. We built, the design to conform to ANSI Z87.1 D3 testing requirements and look to receive industry-recognized certification. We will continue with our scalability analysis and conduct a manufacturing readiness review, to ensure the face shield will have both utility and optimal design for manufacturing. With preliminary sets of assembly instructions and tooling requirements, we will continue to advance our manufacturing, assembly, and distribution networks to drive our BOM and material costs as low as possible, without compromising on the quality of the shield. We will continue to forward our efforts in offering the first reusable face shield at a cost per use equivalent or lower than a single-use disposable shield.