Building an AI that sees the litter we walk past
March 2026
We're building an open-source system that uses two types of cameras — a clip-on device mounted on the grabber and AI-powered glasses worn by volunteers — to automatically detect every piece of litter picked up, classify it in detail, and generate a full report so communities can see the story behind every cleanup.
The goal: turning cleanup walks into data
Every weekend, volunteers go out with grabbers and trash bags to clean up their neighborhoods and highway green-belts. They pick up hundreds of items — 10 to 25 bags of litter each time — but when the walk is over, all that information disappears into a landfill. What if every piece of litter told a story?
That's what we're building — no manual counting, no clipboards. Just walk, clean, and get the data.
How it works: a two-tier AI system
Tier 1 — The Spotter (on-device detection). A lightweight object detection model runs directly on the camera hardware in real time. It spots every piece of litter in the video frame and crops it out for closer analysis.
- Clip-on camera — mounted on the grabber itself, pointing at the grabber head. It captures close-up images at the moment of pickup, with the grabber jaws (~8 cm wide) serving as a built-in size reference.
- AI glasses — worn by the volunteer, capturing a first-person egocentric view of the cleanup scene as they walk and pick up items.
Tier 2 — The Classifier (vision-language model). Cropped images are sent to a more powerful AI — a vision-language model — that determines the category, size, material, condition, whether it's hazardous, and writes a plain-English description of each piece.
Building the dataset
| Metric | Value |
|---|---|
| Images collected | 4,499 |
| Individual labels | 18,464 |
| Litter categories | 71 |
| Collection sites | 4 (Kirkland, Bothell, Woodinville, Bellevue) |
The images span 14 separate cleanup sessions from December 2023 through January 2025. Each image is annotated with bounding boxes and labeled with a detailed category.
Benchmarking the classifiers
We ran a head-to-head benchmark on 241 carefully selected litter images across three leading AI services:
| Provider | Broad category | Exact category | Size accuracy | Cost / image |
|---|---|---|---|---|
| Google Gemini | 73.4% | 23.7% | 83.4% | $0.003 |
| OpenAI GPT-4.1 | 66.4% | 23.2% | 71.0% | $0.010 |
| Anthropic Claude | 59.8% | 12.0% | 79.7% | $0.005 |
Gemini won on both accuracy and cost, making it our primary cloud classifier.
Performance: where we stand
Object detection (Tier 1) — our YOLO26 detection model achieves a mAP50 of 0.905, correctly identifying and locating litter in the frame about 90% of the time.
Classification (Tier 2) — using Google Gemini, we processed all 4,499 images with a 100% success rate at a total cost of about $4.21. Size accuracy 83%, broad category match 73%, material accuracy 37%.
Training a local model — we fine-tuned a vision-language model (Qwen3-VL-8B) using QLoRA on a single consumer GPU (RTX 3080 Ti). After four iterations, our v4 model achieved an eval loss of 0.024 with no overfitting. A working local model would reduce per-image costs by 97%.
What's next
- Deploy on edge devices — shrink the model for real-time inference on the clip-on camera and AI glasses via knowledge distillation and optimized model export
- Connect the end-to-end flow — from data collection with GPS tagging, through detection and classification, to automated report generation for communities and city councils
- Evaluate the fine-tuned model — head-to-head comparison of our v4 local model against Gemini on unseen images
Get involved
- Cleanup organizations — want to pilot the system on your walks? We'll provide the camera setup and handle the AI.
- ML engineers — the codebase is open source, with interesting problems in fine-tuning, edge deployment, and report generation.
- Community leaders — help us understand what data would be most useful for your advocacy and planning.
Reach out at contact@npotechnologies.com — and if you're early-career and want in, see the 2026 internship.