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Pathfinder AI: An Offline AR Trekking Guide Powered by Open-Source AI

What I Built
Pathfinder AI is an offline, wearable AR trekking companion built to keep hikers' eyes on the trail and off their phones.

Instead of constantly stopping to pull out a GPS map or a field guide, Pathfinder AI uses a lightweight heads-up display (HUD) to project non-intrusive directional arrows, trail edge boundaries, and flora/fauna identification directly into your field of view. It’s designed for backcountry hikers, trail runners, and foragers who want to stay fully immersed in nature while safely navigating deep-wilderness areas where cell service doesn't exist.

How I Built It
The core challenge was building an intelligent vision and reasoning system that could run entirely on battery-powered edge hardware (like a Raspberry Pi) without any internet connection.

Local Computer Vision: I used YOLOv8 optimized for edge devices to process the live camera feed. It’s fine-tuned to detect trail edges, natural obstacles (like fallen branches or loose rocks), and local wildlife.

Open-Weight Reasoning: I deployed a quantized open-weight model (Llama 3.2 1B/3B) running locally. When the vision model detects something interesting—like an unfamiliar bird or a split in the trail—the LLM contextualizes it.

Agent Orchestration: Everything is tied together using LangChain and Python. The agent takes the user's pre-loaded GPX route and the real-time YOLOv8 bounding boxes, and decides when to push a minimal text or arrow overlay to the AR display to keep the user on track.

Why Does Open Innovation Matter?
When you are five miles deep into a mountain pass, a closed-source cloud API is completely useless because you have zero signal.

Open innovation is the only reason this project is possible. Running open-weight models and open-source vision frameworks locally means the system works flawlessly offline. It also means total privacy: continuous camera feeds and GPS coordinates are processed on the device and never sent to a corporate server. Finally, having access to open model weights allowed me to strip the AI down to its bare essentials so it could actually run smoothly on portable hardware without burning through the battery.

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Nikola Nikolov •

YOLO plus a 1B on a Pi is a fun build. How much of the battery goes to the LLM versus the vision loop, and did LangChain add lag you could feel on that CPU?