A) Tech Stack (at a glance)
| Layer | Examples | Notes |
|---|---|---|
| Edge compute | Jetson Orin Nano; x86 fanless IPC; Raspberry Pi 5 | Run CV, audio, SDR capture, and SLM (1–3B quantized). |
| Comms | LTE/5G; private LTE/CBRS; depot Wi‑Fi offload | MQTT/HTTPS to cloud; buffered upload. |
| Time & position | GNSS + IMU; optional RTK | Align events to street centerlines and assets. |
| Power & I/O | 12/24 VDC; PoE for cams; CAN/J‑1939 | Isolate noisy loads; surge protection. |
B) Safety & Fire‑Risk Sensing
| Sensor | Role | Notes | Refs |
|---|---|---|---|
| Thermal IR camera | Hot‑spot detection in hopper/body | Automatic alarms on rising temperature | FLIR fire‑prevention • Optris app note |
| CO (electrochemical) | Combustion/off‑gas cue | Pair with temp for early warnings | Honeywell CityTech CO • NIOSH NMAM |
| TVOC (PID) | Organic vapor screening | 10.6 eV PIDs do not detect methane | Ion Science PID guide • RAE PID handbook |
| CH4 (NDIR) | Methane leak/landfill gas | Selective; O2‑independent | Edinburgh Sensors |
| H2S (electrochemical) | Odor/toxicity | Common at transfer stations | Honeywell CityTech H2S |
| Temperature | Context + early fire cues | Pair with CO/TVOC for decisions | US EPA on Li‑ion fires |
C) Environmental & Public Health Sensing
| Sensor | What you get | Typical hardware | Refs |
|---|---|---|---|
| PM (optical dust) | PM1/2.5/10 hot‑spots along routes | Sensirion SPS30; Alphasense OPC‑N3 | SPS30 • NASA trash‑truck AQ case |
| NO2, O3, CO, CO2 | Traffic/combustion mapping | Electrochemical + NDIR modules | City Scanner (2023) |
| TVOC (PID/MOS) | Odor indices; solvent spikes | PID; MOS e‑nose arrays | Ratti 2024 review |
| Methane (CH4) | Leak/plume detection | NDIR CH4; TILDAS for research | Google/EDF Air View • Aerodyne TILDAS |
| Black Carbon (BC) | Diesel soot exposure | AethLabs microAeth | AethLabs • Good et al., 2016 |
| Acoustics | Noise mapping; context for events | Class 1/2 mics; MEMS arrays | City Scanner |
| Micro‑weather | UHI & microclimate | T/RH; globe temp; IR thermometer | Notre Dame 2025 |
D) Operations & Payload
| Sensor/Tech | What you get | Notes | Refs |
|---|---|---|---|
| On‑board scales | Payload; overload prevention | Axle/body/load‑pin systems | Vulcan — refuse |
| RFID (LF/HF/UHF) | Bin identity & service events | DIN 30745 tags; metal‑mount options | HID RFID for waste |
| Ultrasonic/LiDAR proximity | Arm alignment; obstacle detection | Also used for bin fill‑level | Sensoneo |
| Hydraulic pressure/position | Cycle verification; maintenance | Transducers; linear/magnetic sensors | Hydraulic arm sensing |
| IMU/accelerometer | Harsh events; incident recon | In telematics devices | Geotab GO |
E) Cameras & Computer Vision
| Camera | Use | Notes | Refs |
|---|---|---|---|
| Hopper/arm cameras | Recycling contamination; proof of service | Edge CV models flag contaminants | 3rd Eye • Compology coverage |
| Windshield/bumper cams | Road defects; assets; safety | Pothole detection & asset inventories | SmartCitiesDive 2024 • Urban Milwaukee |
| Thermal cam (road) | UHI; wet/failing pavement | Pairs with micro‑weather | See Environmental |
| 360° surround + radar | Blind‑spot reduction; collision avoidance | Integrates with telematics DVR | Heil/3rd Eye Connected Collections |
F) Software‑Defined Radio (RF layer)
One radio + software to observe many bands for diagnostics and research. Restrict demodulation/recording to your own devices, open beacons, and lawful spectrum measurements.
| Use case | Hardware | Bands | Refs |
|---|---|---|---|
| ISM sniffing / coverage checks | RTL‑SDR; HackRF; USRP; SDRplay | 433/868/915 MHz; 2.4 GHz | rtl_433 • RTL‑SDR Blog • HackRF • USRP B210 • RSPdx |
| Spectrum surveys / interference | RSPdx (14‑bit RX); USRP B210 | 70 MHz–6 GHz (B210); 1 kHz–2 GHz (RSPdx) | SDRplay RSPdx • USRP B210 |
| ITS/C‑V2X pilots (authorized) | Front‑ends + SDR + filters | 5.9 GHz | FCC on 5.9 GHz C‑V2X • 47 CFR Part 15 |
G) Acoustic Analysis + SLM (edge)
Use tiny audio models for detection; let an SLM fuse context and write SOP‑style actions and summaries. Store short clips around events; default to features + labels.
Mic choices
- Infineon IM69D130 (digital MEMS), Knowles SPH0645 (I2S), TDK ICS‑40740 (analog MEMS).
Suggested models
| Task | Model | Refs |
|---|---|---|
| VAD | WebRTC VAD; Silero VAD | WebRTC VAD • Silero VAD |
| Keyword spotting | Tiny CNNs on Speech‑Commands | Speech Commands • TFLite |
| Sound events | YAMNet / VGGish (pruned/quant) | YAMNet • VGGish • AudioSet |
| Short ASR (cab) | Whisper‑tiny (quant) | OpenAI Whisper • whisper.cpp |
| Reasoning | SLM 1–3B (quantized) | MLC‑LLM • llama.cpp |
Event taxonomy (starter)
| Group | Event | SLM action idea |
|---|---|---|
| Safety | Siren / Horn / “Stop!” | Pause arm; alert driver; annotate video clip |
| Operations | Arm lift / Bin tip / Hopper slam / Compactor | Auto diary; count cycles; flag exceptions |
| Vehicle health | Belt squeal / Cavitation / Bearing rumble | Maintenance suggestion + depot check task |
| Fire‑risk context | Abnormal hiss/popping | Corroborate with Temp/CO/TVOC; follow SOP |
H) Fleet/Driver/Vehicle Telemetry
| Signal | What you get | Notes | Refs |
|---|---|---|---|
| GNSS + dashcams | Route adherence; safety evidence | Integrates incident video | Geotab waste/recycling |
| J‑1939/CAN | Engine DTCs; fuel; hydraulics | PM & uptime analytics | Vendor docs |
| Cabin CO2 | Ventilation/comfort | NDIR CO2 + T/RH | UCL 2022 |
| TPMS | Tire safety | Direct/indirect systems | Fleetio TPMS |
Governance & Privacy
- Legal & spectrum: Unlicensed bands follow 47 CFR Part 15; for 5.9 GHz C‑V2X see FCC actions.
- Minimize PII: blur plates/faces on‑edge; publish non‑sensitive layers (e.g., potholes, AQ rasters).
- Quality: collocate for calibration; log T/RH; version models/prompts; encrypt and set retention.
- Transparency: document what’s collected, purpose, and retention; community review for AQ programs.
Sources (selected)
- Mobile AQ on trash trucks (NASA/deSouza 2020)
- City Scanner 2023 (mobile sensing)
- Google/EDF Project Air View
- Aerodyne TILDAS methane
- Sensirion SPS30
- AethLabs microAeth (BC)
- Ion Science PID guide • RAE PID handbook
- NDIR Methane (Edinburgh) • Honeywell H2S
- 3rd Eye contamination cams • Compology
- Geotab — waste fleets
- Heil/3rd Eye Connected Collections
- Road/asset CV overview • City pilot news
- 47 CFR Part 15 • FCC on C‑V2X
- rtl_433 • RTL‑SDR Blog • HackRF • USRP B210 • RSPdx
- YAMNet • VGGish • AudioSet
- OpenAI Whisper • whisper.cpp • llama.cpp • MLC‑LLM
- UCL 2022 — Cab CO2
- Notre Dame UHI (2025)