Moving Faster 

Applying Modern Design to Prosthetics

The process for creating prosthetic devices is painfully slow and based on out-dated technology. Digital tools and 3D printing can change everything; they certainly did for Paralympic cyclist, Denise Schindler.

Images courtesy of Autodesk and Dezeen

By Paul Sohi, Product Designer, Autodesk

You may not know much about prosthetic devices. Chances are, unless you know someone who requires one, you haven’t given them much thought.

There are 2 million people in the US who require a prosthesis, with an estimated 185,000 people receiving an amputation each year. But the number of students going on to study biomechanics and becoming qualified prosthetists is declining. It’s a scary thought; we’re slowly marching toward a future where someone could be waiting years for a prosthetic device. This doesn’t even take into consideration children born without limbs, who often are not given a prosthesis in their infancy, as they grow so quickly they need new ones faster than a prosthetist can realistically produce them. This in turn means children who should be “prosthetic native” are not, and when they finally receive a prosthetic, more often than not, they prefer to simply not use the device as it isn’t natural to them — they find it cumbersome.

German Paralympic cyclist, Denise Schindler, discusses her first-of-its-kind prosthetic leg with President Obama and Chancellor Merkel.

Rooted in History

Modern prosthetic design has its roots in the 1500’s — and things haven’t changed much in 500 years. For upper and lower limb prosthetics, sockets — the part of the device that connects directly with the residual limb — their design has not evolved significantly from their early 16th-century predecessors. Initially these sockets were made of carved wood, now there is a standard process of plaster cast molding a limb and building a socket around that mold. The mechanisms that replace joints have remained largely crude as well, with spring lock mechanisms, hydraulics, and other relatively old mechanical techniques used to replace incredibly intricate and complex biomechanics like the human knee. Over time, plastics replaced wood, and now carbon fiber is slowly becoming the standard material for sockets.

Prosthetic technology is evolving too slowly and demand continues to rise. There are no standards of minimum acceptable criteria for prosthetic devices. Instead, each individual prosthetist determines performance and function on a case by case basis. With the high rate of demand and the lengthy process to fit, design, and produce a prosthetic device — each one a customized medical product — prosthetists can’t keep up.

Sadly the results of these problems are felt worldwide, with wait times for a prosthesis often lasting as long as six months, with no guarantee of a comfortable fit due to the analogue processes used to create devices. The body can also change enough in six months to render a new device largely unusable.

I’m not a prosthetist, I’m a product designer, but I’ve found myself specializing in prosthetic design. When I learned about the state of prosthetics and the lack of new technology, I won’t lie, I was angry — but that anger spurred me to action. No one in need of prosthetic care should have to wait for a device in the era of digital technology and 3D-printing. In 2015 I joined Autodesk, a software company that helps people make anything — and in my first week I was assigned a project in Germany with Denise Schindler, a Paralympic cyclist. Our aim: to explore whether it was possible to use digital technologies and processes to augment prosthetic creation, and wherever possible, replace analogue processes if it would mean a prosthetic device could be made faster and better.

Let’s get digital.

Before we talk about improving the process of creating a custom prosthesis, it’s important to understand the existing process. When a patient meets with a prosthetist, they have an initial consultation, then a plaster cast mold of their limb is created. This is a standard mold-making process reminiscent of plaster molds for ceramics. Because plaster shifts as it dries, a few molds are made, then filed and cleaned to ensure the most accurate cast of the residual limb.

My first attempt at modernizing the prosthetic production process involved using a $250 piece of equipment, a 3D scanner. With it we were able to produce an accurate three-dimensional model of Denise’s leg in less than fifteen minutes. In less than a day, we demonstrated we could radically improve the first step of the process — perhaps in the future prosthetists wouldn’t even need to bother with plaster!

There was cause to celebrate and it was time to assemble a team of great designers and engineers to take this initial success and turn it into a real solution for Denise. I was based in London, our prosthetists were in Nittenau, Germany, our Autodesk mechanical engineer, Taylor Stein was based in San Francisco; my intern, Myles Cooper was in Portland, OR; and our advisor, Mickey Wakefield, was in Munich. We had a team of experts working across the world, digitally synchronized, to redesign prosthetic care.

The Autodesk team created a detailed 3D scan of Denise’s leg to produce a better fitting socket in a fraction of the time.

Concept Car

As many product designers are apt to do, the next thing we did was produce a concept model; a visual prototype of a device that pushed the envelope with total disregard for budget or technology limitations. You often see this approach with concept cars. Car manufactures create a future concept and make it real enough to inspire the next generation of production vehicles.

The concept-car-prosthesis we showed Denise was lightweight — made from carbon fiber and polycarbonate — with smart textiles integrated into the socket. It had a removable, onboard computer that would give Denise real time feedback on her device’s performance. It even had “speed-holes,” which actually weren’t terribly aerodynamic we came to find. The concept model was beautiful. We set ourselves to making version one based on that vision, and we failed. We had 3D-scanned a limb, but that didn’t turn us into trained prosthetists overnight. Denise and her team schooled us on her particular amputation: the base of her limb is extremely sensitive, the flesh and muscle that grew there is very thin, and so even the mildest amount of pressure on it can be excruciatingly painful for her. In some areas we could innovate, and in this case we needed to figure out how to replicate what Denise’s prosthetists had mastered for her years ago: a socket that grips around the knee in a comfortable, but efficient way, to drive thrust down into the bicycle without causing Denise pain. Our version one socket didn’t cover nearly enough of Denise’s limb to make this possible.

3D printing the prosthesis drastically reduced production time and created a device more reminiscent of our own natural biomechanics.

Stepping Up

In design, failure is merely iteration. We learned a lot in a short amount of time to design an effective, Olympic-level prosthetic device for Denise. But how to make it real? Prosthetic devices are a custom product every single time, they are not interchangeable between patients, and as we’ve established, they take a really long time to make.

Prosthetists are starting to use carbon fiber to make ultra-lightweight, durable sockets, but carbon fiber parts take time, and they are extremely rigid — the human body isn’t. We’re 60% water, so imagine what happens when you put an already sensitive amputated limb into an extremely rigid socket. Even with a silicone liner, sores, lesions, and bleeding can occur, especially for Denise who expels more energy on her prosthesis than most.

3D printing opened up many opportunities for us to address the time and rigidity issues. While carbon fiber is a uniform material — meaning it has the same thickness everywhere — 3D printed parts can be thicker in some places, thinner in others, more akin to our natural biomechanics. With this production technology we could analyze Denise’s driving forces, design a socket that perfectly aligned to those needs, and build a one-of-a-kind, comfortable prosthesis.

By December 2015, we created our first production model, a fully 3D-printed prosthetic device, with an intelligent socket. We used polycarbonate plastic, and utilized its natural material properties to produce a socket that was more flexible in areas where Denise needed comfort, and stiffer in areas where she could effectively drive force into the bicycle. The net result was a prosthesis that was more comfortable, without sacrificing performance, which for Denise meant being able to ride at maximum effort for longer.

Denise then did the one thing we asked her not to do: the very next day after trying this leg on for the first time, she took it to the velodrome and started training on it. We weren’t sure if it was going to stand up to the forces she would exert on it, we were in uncharted territory — no one had ever attempted to produce a prosthetic leg this way before! Thankfully it didn’t break, and Denise was setting new personal best times using the device.

As an added benefit for Denise, we designed the leg in two parts. She has the ability to remove the bottom piece and replace it with a longer element to adjust to different ride heights and bicycles. We also added an aluminum plate with threaded elements, which allows her to adjust not only the position, but also the attachment angle of her cleats to the pedals. We listened to the prosthetists too — Denise wears a special rubberized neoprene sock between her leg and the socket. A small vacuum cap on the back of the device creates an airtight seal — as her limb moves, any excess air is pushed out and can’t get back in, creating the best fit possible.

Never Stop Spinning

Between May and December 2015 we went from a team who knew next to nothing about biomechanics to a group that had produced a one-of-a-kind prosthetic device. This was all made possible by infusing digital technology and 3D printing into the process, and remaining informed by the deep knowledge of our prosthetist partners. We took a process with a normal lead time of 6-10 weeks and cut it into 10 days; producing a prosthetic that was only 200 grams heavier than its carbon fiber counterpart — and we still had nine months to iterate before the Paralympic Games in Rio de Janeiro.

Denise would always tell us to never stop spinning. We didn’t. Over the course of the next eight months leading into August, we would reach a total of 72 design iterations on the prosthesis, some minor, some major changes and refinements. At this point we had comfortably reproduced the process for creating a prosthetic device digitally, introducing virtual simulations to see how it would behave in the real world, testing the physics of the prosthetic itself, as well as rudimentary simulations that could give us an idea of how the prosthetic would perform for comfort.

Using 3D printing not only helped lay the foundation for a new process for masscustomization of prosthetics, it helped us reduce the overall weight of the device. Using a cutting-edge tool from Autodesk, Netfabb, we were able to intelligently design the inside of each 3D-printed part. Typically 3D-printed parts have a simple lattice fill technique, but we were able to add structure in some places, remove it in others — all informed by our digital and physical tests — to create a prosthetic leg for Denise that was as light as physically possible without compromising performance. This work even further reduced our production time.

The First Ever

In September Denise was on her way to Rio with her new prosthetic leg in tow, built from start to finish in less than 48 hours, costing less than $500, and ready for racing. She became the first Paralympian to compete with a fully 3D-printed prosthetic. Denise won silver and bronze medals in two events she had not medaled in before — the team and I were so proud.

I have been openly sharing our design and engineering techniques with every prosthetist interested, and am in the process of creating a series of videos, tutorials, and learning content on how to create prosthetics in the 21st century using digital tools and innovative fabrication. We need prosthetists to understand and utilize these techniques in order to solve the persistent issues in prosthetic care.

For myself and the team, the legacy of this project is what matters most. Denise continues to smash records and reigns as a world champion on a prosthetic device we made for her using a method that had never been tried before. We’ve trained numerous prosthetic studios and prosthetists in the methodology, and seen our work improved upon and modified in an explosion of creativity and problem solving. The future of prosthetics and medical hardware in general is only going to improve from here, and I am proud to have contributed to that future.

Compact Urban Living

The Search for New Affordable Housing Typologies

Living in Boston is great, if you can afford it. A new design methodology for housing might hold the key to both affordability and livability.

Images courtesy of Stantec

By Adam Gonzalez, Design Coordinator, Stantec

Boston routinely ranks notoriously high when it comes to lack of housing affordability — a ranking not many Bostonians are excited to boast about. If you are an average renter living in Boston, it’s likely that you are spending over one third of your annual income on an apartment, a staggering amount that experts considered “rent-burdened.” In 2016 Boston was listed fourth, after San Francisco, New York City, and San Jose, as the most expensive city to rent in (1). The average monthly rent in Boston since December 2017 was $2,800. For a studio, rent is just over $2,200 per month; a 1 bedroom apartment averages around $2,700, and if a bedroom or two is added, the rent jumps another $1,000 per bedroom. And those number are climbing (2, 3).

In 2012, a group of young Boston architects working at ADD Inc, now Stantec — impacted by the high rental cost — came together to brainstorm design solutions for this widespread problem. We called ourselves WHAT’S IN? and set a goal to find accessible urban housing solutions. Over the course of five years, we attracted many like-minded people, gathered data on housing preferences, designed affordable housing prototypes, cultivated collaborations, and created an idea-sharing platform to help tackle housing affordability in Boston.

Build to Learn

Land comes at a premium in Boston. Any parcel remotely near the city core is going to have a high price tag. Add in the high cost of labor and a lengthy permitting process, and you get expensive housing. This is only part of a complex problem. Boston’s housing stock is extremely lopsided away from demand for 1 bedroom units and studios. Only 14% of Boston’s housing is 1 bedroom apartments, and only 2% of units are studios — that is extraordinarily low especially when taking into account that the vast majority of housing demand in the city comes from individuals and couples.

To generate interest and spur conversation on housing in Boston, WHAT’S IN designed a full-scale mockup of a 300 square foot apartment based on feedback gathered from a series of focus groups of young professionals.

Despite diverse demographic backgrounds, the majority of the focus group participants ranked “affordability” as the number one concern when it came to housing. In addition, regardless of the higher cost of urban living, an overwhelming percentage of these young professionals wanted to live at the center of urban life and be connected to their friends. When asked what their preferences on unit interiors were, many participants responded that “storage space is a must,” “only a small kitchen is needed, we don’t cook much at home,” “Murphy beds and other movable furniture was for architecture nerds” and “natural light was highly desired.” All of this feedback became design inspiration for the 300 sf WHAT’S IN mockup. We developed a conceptual solution that could satisfy many of these housing priorities: Compact Urban Living. We broke it down into four categories: Affordable, Sustainable, Social, and Optimizable.

Compact Units

Compact units have a smaller footprint, making them less expensive to build and maintain. A smaller footprint requires less electricity required to heat and light. Compact urban units are intended to be located around transit nodes allowing residents to utilize mass transit and car sharing options, thus lowering their overall carbon footprints. When combined to form a building, compact urban units allow for more social amenity spaces within the same footprint as a traditional apartment structure. Therefore, this typology offers more opportunity for social interaction with your community than traditional housing.

Neighborhoods can optimize their available parcels by building compact urban apartments, which can help balance their housing stock. By providing more studios and one bedroom apartments, the existing housing stock can be relieved of its exhausted state. The unhealthy disparity between supply and demand has been one of the factors that transforms neighborhoods like Boston’s Mission Hill to completely displace the existing family housing stock. The triple decker, a once family oriented workforce housing typology, transformed into overflow housing for students. With a severe deficit of affordable studios or one bedroom apartments on the market, what was once family-oriented housing became off-campus dormitories.

Fast forward five years and compact units have taken hold in the Seaport “Innovation District,” the only neighborhood in the city where units under 450 sf are allowed. Coincidentally, this district has some of the highest land values in the region, which has driven up the price of the compact units, making it difficult to communicate the benefits behind density and compact housing as a solution for affordable housing. If all the compact units are out of most residents’ price ranges, then their purpose as affordable workforce housing hasn’t been achieved. We must deploy Compact Urban Living in less expensive neighborhoods to realize its true benefits.

Urban Housing Unit

To simulate a tangible experience for residents, we needed to fabricate a physical prototype. In 2016, led by Mayor Walsh’s Housing Innovation Lab, BSA president and Stantec Principle Tamara Roy, and Livelight’s Addison Godine, the Urban Housing Unit (UHU) was created. The UHU was a 385 square foot apartment that traveled to various Boston neighborhoods with the mission to demonstrate what life could be like in a welldesigned and affordable compact apartment. We designed a series of neighborhood outreach activities with the Housing Innovation Lab during the UHU roadshow. While traveling with the UHU, over 2,000 residents were interviewed in Roslindale, Dorchester, Roxbury, Mattapan, East Boston, Allston, and Brighton. We discovered that while 385 sf seemed like an unfathomably small unit for most UHU visitors, when the team walked these concerned individuals into the UHU they were surprised by the abundance of natural light, warm hardwood floors, and cozy furniture. There was a full kitchen, a spacious bathroom, variety of seating areas, and a bed that didn’t fold into the wall. Most of these skeptical residents completely changed their view on Compact Urban Living. Overall, 98% of the visitors said either they, or someone they knew, could live in a compact urban apartment like the UHU.

Along with talking and welcoming residences into the UHU, WHAT’S IN created a board game called Micropoly, where residents were given WHAT’S IN bank notes based on household sizes and were asked to spend them on either compact living or traditional apartment sizes. Whatever money remained could be spent on urban amenities like public transit, open spaces, access to grocery, parking, and storage. The game had an educational message: we all must prioritize our requirements for housing. When larger units are preferred, one might have to forgo the convenience of living downtown. On the other hand, adapting to smaller living quarters could mean more access to urban amenities. The Micropoly participants also revealed a strong need for a variety of compact typologies, ranging from studios to family housing with more bedrooms.

The UHU helped the city assemble a collection of feedback from community members on ideas, comments, concerns, and excitement on the compact urban typology. With the majority of comments being positive, the city moved forward on creating a request for proposal focused on compact urban housing in the Garrison Trotter neighborhood of Roxbury.

Hearth House

In response to the City of Boston’s request, WHAT’S IN developed Hearth House, a compact urban housing typology focused on affordability and communal living. Historically the hearth has been the center of the home. Families gathered by the fire for warmth, and to cook and eat meals, thus the hearth became the core housing design element. The design for Hearth House prioritizes spaces where communities are formed, where residents could gain a sense of belonging. We were particularly interested in creating a space for multigenerational living — Compact Urban Living is not just for millennials.

We examined the New England housing vernacular of the triple decker, a typology rooted in housing the workforce of the region in the last century. The Hearth House is a modern-day interpretation of the triple decker, as the city seeks yet again to find the most efficient way to house its growing population. From the street, the building fits into its neighborhood with contextual massing, siding facade, and pitched roofs. A communal bridge, overlooking a courtyard, connects the two residential sections of the building. The two residential sections of the building feature uniquely designed compact units. The apartments range from studios to three-bedrooms at 850 sf.

The smallest studios are sized at 325 sf. These cozy interlocking units include a full kitchenette — including an under counter fridge, 2-burner cooktop, microwave convection oven, counter space and a sink — a full bathroom, and enough space to comfortably fit a full size bed, small sofa, and other furniture. The other units are much like traditional one, two, and three bedroom apartments, just a little tighter and more efficient in their spatial arrangements. With all the compact units, Hearth House increases housing density without exceeding the neighborhood contextual height.

The ground floor of the building houses a foyer with bike storage, a spacious communal living room with a children’s play area, a dining space large enough to host a building wide party, a co-working space, and a shared commercial size kitchen; all of the ground floor spaces overlook and have access to the central courtyard.

The bridge is stocked with amenities as well, with a fully furnished, comfortable living room, dining space, and a large kitchen; residents are provided with the opportunity to gather and meet their neighbors throughout their day. Hearth House seeks to promote social interaction and foster a sense of community. Whether one is an introvert or an extrovert, the opportunity to meet someone new is always available.

Thanks to its wood frame construction, subsidized land cost, and high floor efficiency and density, the studios could be priced at $1,000 per month — half the average rent in the same neighborhood.4 The idea for Hearth House is to deploy multiple instances of these compact typologies throughout neighborhoods. Hearth House like developments increase density and strengthen the housing stock, especially when built around public transit.

Searching for Typologies

With Boston’s population growing, the demand for housing is increasing dramatically. The current housing supply is exhausted and simply cannot keep up. Compact units can help satisfy demand while being an affordable, sustainable, and a social housing alternative. When the UHU toured around Boston, the feedback was overwhelmingly positive. An efficient, well designed compact unit is bright, spacious, and livable — and when these units are pieced together to form a building, the typology can house multiple social amenities that provide the opportunity for residents to engage in social interactions. Density comes in all shapes and sizes; it doesn’t have to be a high-rise in a triple decker neighborhood; it could mean optimizing a floor plan to achieve a higher number of compact urban units.

WHAT’S IN continues to work towards creating a typology to improve housing in Boston, as well as incorporating our research and design thinking in Stantec projects around the country. We’re collaborating with the City of Boston and other groups with similar interests to make housing more affordable. We continue to research alternative methods to help drive cost down as well. When modular, or prefabricated, construction is paired with compact urban housing it can create an even more affordable and efficient system that can quickly add more units to a neighborhood’s housing stock.

The next step for us is developing a platform to inform and encourage residents to attend neighborhood meetings to support denser more affordable growth within their own neighborhoods. With a greater spectrum of voices, neighborhoods can grow and satisfy their housing needs through community and smart design.

The 300 sf prototype showed what life could be like in a compact studio.

Sources

(1) O’Brien, D., Z., Chen, C., Greer, A., & Niemeyer, B. (2016, June 17). Zumper National Rent Report: June 2016. Retrieved January 03, 2018, from https://www.zumper.com/ blog/2016/05/zumper-national-rent-report-june-2016/

(2) Boston, MA Rental Market Trends. (n.d.). Retrieved January 03, 2018, from https://www.rentcafe.com/average-rent-markettrends/us/ma/boston/

(3) Bluestone, B., Tumber, C., Huessy, J., & Davis, T. (2016). The Greater Boston Housing Report Card 2016. Boston, MA: The Boston Foundation. doi:https://www.northeastern.edu/ dukakiscenter/wp-content/uploads/2016/11/2016-HousingReport_R2.pdf

(4 )Boston, MA Rental Market Trends. (n.d.). Retrieved January 03, 2018, from https://www.rentcafe.com/average-rent-markettrends/us/ma/boston/