Participant | About

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About Us

Our Purpose

We believe everyone, everywhere deserves the mobility they need to participate fully in life. No one left behind.

Who We Are

Founded as a Benefit Corporation in 2018 in San Francisco, Participant was born out of a critical global crisis: the need for high-quality, supportive wheelchairs that children need to thrive.

Traditional medical devices are often bound by inflated pricing and designed without the real-world environments of global users in mind. Without a supportive, properly fitted wheelchair, a child misses out on school, community, and a future.

We set out to change that, for kids and adults. At Participant Assistive Products, we blend market-based commercial scaling with a strict social mission. We design and distribute durable, clinically tested mobility products co-created in direct collaboration with the disability community. Most of our team are assistive technology users themselves, so testing and feedback come directly from the people who understand the need best.

What We Do

We design and distribute high-quality, ISO-tested mobility solutions built for the real world. Our portfolio serves diverse lifestyles, tough terrain, and seamless transportability:

Cub: Our flagship pediatric tilt-in-space chair that expands as a child grows, preventing deformities and giving kids with complex postural needs a seat at the table.
Wildebeest: An all-terrain powerhouse built for rural paths, rugged terrain, and outdoor exploration.
Pony: A highly transportable chair designed for urban use, independent driving, smaller spaces, and easy travel.
Springbok: A rigid active wheelchair that is lightweight, stylish, and built to keep up. Springbok is made for work, play, and everything in between.

That's four major hardware releases in eight years, through COVID, with more coming soon. Watch for a world-class pediatric active wheelchair, a light and breathable cushion, and an amazing new walking aid.

In startup business circles, it is said, "Hardware is hard." We take that challenge a step further by building medical devices at low cost, so they're accessible to our brothers and sisters who are economically marginalized.

People with mobility disabilities need physical assistive technology.

No app or algorithm can replace a wheelchair, a cane, or a walker. AI and software are transforming healthcare, but AI on its own will not help a grandmother avoid a fall, nor will it help a child cross a playground to meet new friends. Physical assistive products are difficult to design, manufacture, and deliver, but they remain essential. We're the kind of team that takes on difficult problems, not the ones that are cheapest to solve.

We believe...

everyone, everywhere deserves the mobility they need to participate fully in life. No one left behind.

Our Global Impact Model

We don't just build great chairs; we solve global access. Our team identifies and builds sustainable networks of commercial distributors in regions traditional manufacturers overlook. NGOs and local foundations remain valued partners, but our defining achievement is a growing distributor network that keeps delivering mobility long after any single donation ends.

Participant was founded in 2018 by four friends whose careers had already taken them deep into the world of assistive technology: Keoke King, Wayne Hanson, Dave Calver, and Ryota Yamada. Together, they bring over 100 years of combined experience, having designed 200+ assistive products and served wheelchair users in more than 40 countries.

Keoke's path started with his grandmother's struggles with a bulky, poorly fitted wheelchair and cane, and led him through supply chain and product roles across seventeen countries before he launched CLASP, a global assistive product supply chain initiative, at UCP Wheels for Humanity (now Momentum).

Wayne co-founded his first pediatric wheelchair company in 1990 and has spent decades developing seating systems for children with disabilities worldwide.

Dave, a Canadian Occupational Therapist and wheelchair user himself, has lived and worked in wheelchair seating and development overseas for more than 25 years. Ryota is one of the world's leading wheelchair designers, with 130+ chairs to his name; he balances performance, comfort, and low-cost manufacturability. Over 500,000 people use Ryota's designs today.

We combine market-based scaling with a missional core. By mastering large-scale, quality-assured manufacturing, we make advanced assistive products affordable without compromising quality. Our global network has delivered products to more than 40 countries, enabling NGOs, governments, ministries of health, and commercial distributors to serve more people with the same resources.

Our manufacturing partners are ISO 13485-certified, our wheelchairs are ISO 7176 compliant, and our products have supported more than 6,000 children worldwide. Our work has been recognized through selection for the 2022 Cerebral Palsy Alliance Remarkable Accelerator and the University of Central London Global Disability Innovation Hub, AT Enterprise Studio - Top AT Startups 2025, winning the 2024 ASME ISHOW Innovation Showcase, and receiving a Zero Project Award in 2026. We are committed to answering the WHO's call to expand access to assistive technology to everyone.

What's Working and What's Next

We have discovered that millions of people need high-quality mobility products that fit their unique needs and are priced within reach. Through frugal engineering and user-centered design, we develop life-changing assistive products that are both clinically effective and affordable. Our tiered pricing model lets us serve both the most financially marginalized, through NGO partners, and the underserved middle market long overlooked by traditional US and European manufacturers.

We continue to find major gaps in the mobility market, where products are too expensive, poorly suited to rugged environments, or unnecessarily complex. We listen to users, stay true to our design principles, and see opportunities to expand access to better mobility solutions while building a sustainable business.

The Team

Keoke King

Chief Executive Officer, Co-Founder

Keoke’s first encounter with disability was while being cared for by his grandmother. Her assistive products, a cane and a rudimentary wheelchair, were bulky and did not function well for her daily activities, especially outdoors. To design projects, Keoke brings a user-centered approach and attention to affordability. He loves to find market-based, scalable solutions that serve basic needs and his career in international development has taken him to seventeen countries for roles in marketing, supply chain, product development, and sales. In his last role, Director of Social Enterprises at UCP Wheels for Humanity, he launched CLASP, which is a supply chain solution designed to improve the access and affordability of appropriate assistive products globally. Previously, Keoke was Marketing Director at Whirlwind Wheelchair after his MBA studies at San Francisco State University. Keoke lives in San Francisco with his wife, Chris

Wayne Hanson

Product Developer, Co-Founder

Wayne grew up in Montana and currently lives in Bozeman, Montana with his wife Lee Ann. Nearby are Wayne’s two children and five grandchildren. Wayne loves developing and delivering innovative products for children with disabilities to help them reach their greatest potential. Wayne and his wife co-founded their first wheelchair company, Kid-Kart Cares About Kids in 1990. Kid-Kart was a pioneer in providing freedom of mobility and therapeutic support for children with disabilities during their formative years from age one to age five. Wayne has since developed numerous products that serve children and adults with disabilities worldwide, including innovative dynamic seating systems that provide freedom of movement for children in their wheelchair. Wayne is the co-founder and currently the Executive Director of Reach Out and Care (ROC Wheels), a non-profit organization dedicated to providing seating and mobility products for people with disabilities in less resourced countries. Wayne has joined Participant because he believes in doing everything he can to help mobilize people with disabilities throughout the world.

Dave Calver

Chief Clinical Officer, Co-Founder

Dave Calver is a Canadian Occupational Therapist who has dedicated his career to working with wheelchair seating and in wheelchair development in less resourced countries. He is a wheelchair user who participates in a great variety of outdoor sports and enjoys introducing other individuals to the outdoors, particularly fellow wheelchair users. He has been living and working overseas for more than 25 years and currently calls Nicaragua home.

Ryota Yamada

Chief of Design & Innovation, Co-Founder

Ryota is one of the leading wheelchair designers in the world. He has developed over 130 wheelchairs from quick court chairs for basketball, to skate-park big jump chairs with suspension, to stylish daily use chairs, and some of the most robust chairs available today. He weaves simplicity and user understanding into designs. And, he has a knack for achieving a balance between high performance, user satisfaction, and low unit production cost. He enjoys bicycling and craft beers of all kinds. We have Yoda on our team!

Advisory Board

Greg Barret

Greg brings rigorous finance and accounting standards to Participant's books. As a CPA, he is building a career in medical devices and life sciences companies, including Bolt Threads in the SF Bay Area. Building the finance systems of scrappy startups into well oiled machines is his forte. "Human health and wellbeing are pillars of any great society. In my day to day, we push forward the leading edge of new health technology. It is satisfying to me to work with Participant to also bring underserved and vulnerable people forward toward good life and inclusion."

Mark Burger

Mark’s background includes wealth management, institutional trading, and co-managing a hedge fund. He has been active in finance both on the advisory side and as an angel investor in numerous companies over the past 35 years. Mark holds a B.S. in Genetics from the University of California, Berkeley and an M.B.A. , awarded with honors, from the Graduate School of Economics and Business Administration at Saint Mary’s College. Additionally, he completed a Certificate in Accounting for Financial and Business Analysts, awarded with distinction, from the extension program at the University of California, Berkeley.

Ralf Hotchkiss

The struggle for disability rights and equality has taken Ralf far off the beaten path. "I was recognized with the MacArthur Genius Award for advancing independent living for wheelchair users by localizing wheelchair manufacturer. At the time, in 25 locations, now they have replicated and we've lost count." Ralf is co-founder of Whirlwind Wheelchair and lives in Oakland with his family. "Participant is carrying forward a vision for inclusion for all that is both self-evident and disruptive."

Lal Ninan

Lal Ninan, Ph.D., is an experienced technical and regulatory professional with over 16 years of experience in the medical device and pharmaceutical industry. An engineer by training, he is passionate about enabling life science businesses develop global products that heal and restore health and quality of life in an affordable manner. Lal is excited to join the advisory board and contribute to realizing Participant’s vision of providing quality assistive products to disabled children worldwide.