TrailSense

What it does

TrailSense is a pair of smart sunglasses that guide blind hikers by enhancing natural sounds to convey the location of nearby obstacles—offering spatial awareness without disrupting the outdoor experience.

Your inspiration

“While the benefits of being in nature are the same for everyone, the risks are not.” For 30+ years, Esther Gallego has supported blind individuals in their daily lives as a rehabilitation technician at ONCE — Spain’s National Organization for Blind People. A family friend, her reflections on accessibility deeply shaped my thinking: “Accessibility is holistic and universal. It goes beyond the practical and into all dimensions of a good life — from leisure to culture, nature to sports.” These conversations inspired me to explore how design can move beyond urban, functional contexts and open up access to beauty, joy, and connection in nature.

How it works

Using the familiar form factor of hiking sunglasses, TrailSense features an array of Time-of-Flight depth sensors to map the environment ahead. Using this data, a compact processing unit on the side will modify the ambient sounds recorded by a microphone placed at the center of the frame, making them progressively louder in the direction of nearby obstacles. To ensure a natural and pleasant experience, TrailSense runs a sound processing pipeline that includes a dynamics processor to suppress loud noises, a machine learning classifier to isolate natural ambient sounds, and a low-pass filter to remove sharp, high-pitched tones. The result is a smooth, real-time audio enhancement delivered through bone-conduction speakers embedded in the arms of the glasses —offering spatial cues without isolating the user or masking the surrounding soundscape.

Design process

The project began with insights from Esther Gallego, a rehabilitation technician at ONCE with over 30 years of experience helping blind individuals in their daily lives. In our conversations, we reflected on how accessibility often neglects natural, unstructured environments. Esther connected me with two key groups: on the technical side, Manuel Valentín, a developer of accessible technologies for ONCE, who helped me explore why many assistive technologies fail in outdoor settings. On the social side, I was connected with volunteers from Pandetrave, an inclusive mountaineering club. From them, I learned how beginner blind hikers often feel hesitant to join due to reliance on unfamiliar guides and the lack of effective tools—especially since white canes are limited on rough terrain. With these learnings, my goal became to help beginner hikers build confidence by enhancing spatial awareness in a non-intrusive way. Conversations with blind hikers from Pandetrave and TAVIP (UK) revealed that current tools feel disruptive. I iterated through prototypes—from harnesses to haptic handhelds—before arriving at discreet sunglasses using directional sound. The final version was tested in the UK by a TAVIP volunteer, iterating the design for maximum comfort, clarity, and signal balance.

How it is different

"When I'm out in nature, I don't want a lot of artificial noise... it would be jarring, irritating" — G., Blind Hiker. TrailSense embraces the unique context of hiking and enhances it, instead of interrupting the experience in nature. Unlike many assistive tools that rely on artificial sounds or spoken instructions—which can feel intrusive, alienating, or overwhelming in natural settings—TrailSense builds on the sounds already present in the environment. By subtly amplifying these in the direction of nearby obstacles, it provides clear spatial awareness without breaking immersion. This intuitive, audio-based guidance feels organic and preserves the shared experience of hiking with others. It doesn’t isolate the user or demand constant attention. Instead, it complements the natural rhythm of the trail, balancing functionality with emotional resonance, so users are more likely to keep using it and enjoy doing so.

Future plans

I’m currently refining the latest prototype and preparing it for a new round of field tests with UK-based testers. Current feedback already highlighted ways to improve the experience—such as customizable alerts, haptics for last-call warnings, and sound presets to match preferences. I’m also exploring computer vision to detect terrain features not picked up by depth sensors, like snow, ice, or creeks. Longer-term, I aim to link TrailSense to a collaborative app that shares hiking routes and highlights interesting points. Development will remain guided by blind hikers to ensure it stays inclusive, intuitive, and meaningful.

Awards