For a person with foot drop, the simple act of walking becomes a careful calculation. Each step risks a stumble, a trip, or a fall, often necessitating a rigid, plastic ankle-foot orthosis (AFO) that can be uncomfortable and stigmatizing. A new Cambridge-based startup, Sole 1, is proposing a different path: a soft, robotic sock that uses artificial intelligence and synthetic muscles woven into fabric to actively lift the foot with each stride. It is an ambitious attempt to replace a decades-old standard of care with something that looks and feels like ordinary clothing.
The Wedge: Softness Over Rigidity
Sole 1's core bet is that wearability and comfort are the primary barriers to adoption for existing foot drop devices. Traditional AFOs are often bulky, can cause skin irritation, and are visibly medical. The company's product, branded Sole¹, aims to address this by embedding its actuation system directly into a textile sock. The technology uses AI to track the wearer's gait in real time, then activates fabric-based synthetic muscles to provide a precisely timed assist during the swing phase of walking [Perplexity Sonar Pro Brief, retrieved 2024]. This positions the device not just as a passive brace, but as an active mobility aid with a rehabilitative component.
The concept emerged from a student project at Harvard and was named the US 2025 National Winner of the James Dyson Award, a prestigious international design and engineering competition [James Dyson Award, 2025]. Founders Bradley Wagman and Viktor Bokisch, both engineering students, are leading the company from its academic roots toward a commercial medical device [Boston University News Service, 2026]. The award provides non-dilutive funding and validation, but the road from a celebrated prototype to a cleared, reimbursable medical product is long and capital-intensive.
The Path to Patients
At this pre-seed stage, Sole 1's public traction is measured in design accolades rather than clinical data or commercial sales. The company has not disclosed any venture funding, and its website functions primarily as a marketing showcase for the award-winning concept. The next critical hurdles are clear, and they are significant. The device will require FDA clearance, likely through the 510(k) pathway, which demands rigorous testing for safety and substantial equivalence to a predicate device. Furthermore, to reach the patients who need it, the company must eventually navigate the complexities of insurance reimbursement, a process that often hinges on demonstrating improved clinical outcomes and cost-effectiveness compared to existing AFOs.
The competitive landscape for foot drop assistance is not empty. Established players market functional electrical stimulation (FES) devices, like those from Bioness, which use electrodes to stimulate the peroneal nerve. These avoid rigid bracing but introduce their own challenges with electrode placement and consistent stimulation. Sole 1's synthetic muscle approach represents a different technical philosophy, prioritizing mechanical assistance integrated into everyday apparel. Its success will depend on proving that this approach is not only more comfortable but also equally or more effective at preventing falls and improving gait mechanics.
For the estimated patient population dealing with foot drop,often a result of stroke, multiple sclerosis, cerebral palsy, or spinal cord injury,the current standard of care remains the plastic AFO. It is a reliable, low-tech solution prescribed by physiatrists and orthotists for decades. Yet, its limitations in comfort and aesthetics mean many patients abandon their devices, trading safety for dignity. Sole 1 is betting that a softer, smarter alternative can finally solve that trade-off.
Sources
- [James Dyson Award, 2025] Sole¹ project page | https://www.jamesdysonaward.org/en-US/2025/project/sole
- [Boston University News Service, 2026] Profile on student founders modernizing mobility devices | https://bunewsservice.com/from-robotics-class-to-start-ups-meet-the-engineering-students-who-are-modernizing-mobility-devices/
- [Boston Globe, September 2025] Harvard engineering students create robotic sock for disabled people | https://www.bostonglobe.com/2025/09/15/business/harvard-robotic-sock-ai/