Difference between revisions of "Introduction"
Jump to navigation
Jump to search
(Reframe: bcMeter (DIY) / source-available) |
(Consistency: 'open design/PCB' -> 'source-available' per licensing decision) |
||
| (One intermediate revision by the same user not shown) | |||
| Line 5: | Line 5: | ||
The device operates "headless" — it has no built-in screen. Instead, it hosts its own website that you can access from any smartphone or computer connected to the same network. | The device operates "headless" — it has no built-in screen. Instead, it hosts its own website that you can access from any smartphone or computer connected to the same network. | ||
The software is source-available — freely available for private, educational and research use (CC BY-NC 4.0): [https://github.com/dahljo/bcmeter github.com/dahljo/bcmeter] | The software is source-available — freely available for private, educational and research use (CC BY-NC 4.0): [https://github.com/dahljo/bcmeter-pi github.com/dahljo/bcmeter-pi] | ||
=== Device Types === | === Device Types === | ||
* '''bcMeter (DIY)''' — The source-available, self-build version. Runs on a Raspberry Pi using the | * '''bcMeter (DIY)''' — The source-available, self-build version. Runs on a Raspberry Pi using the source-available PCB design, freely available for private, educational and research use (CC BY-NC 4.0). Build your own from the source-available design files and the Wiki (nothing is sold). | ||
* '''bcMeter Kit''' — Assembled-instrument PCB plus components for self-assembly and 3D printing. Available on request. | * '''bcMeter Kit''' — Assembled-instrument PCB plus components for self-assembly and 3D printing. Available on request. | ||
* '''bcMeter Complete''' — Fully assembled, ready-to-use instrument on a compact platform that starts in seconds and updates over the air, with no microSD card or Linux system to maintain. Available on request. | * '''bcMeter Complete''' — Fully assembled, ready-to-use instrument on a compact platform that starts in seconds and updates over the air, with no microSD card or Linux system to maintain. Available on request. | ||
| Line 25: | Line 25: | ||
# Data is saved as CSV and displayed in real-time on the web interface | # Data is saved as CSV and displayed in real-time on the web interface | ||
'''Multi-wavelength:''' | '''Multi-wavelength (in development):''' Additional 520 nm and 370 nm channels for source apportionment via the Ångström Exponent (AAE) are in development and '''not available in shipped hardware'''. Current devices measure at 880 nm only. | ||
=== Sensors & Capabilities === | === Sensors & Capabilities === | ||
| Line 35: | Line 35: | ||
|- | |- | ||
| Black Carbon (BC) || Optical absorption at 880 nm || Primary measurement | | Black Carbon (BC) || Optical absorption at 880 nm || Primary measurement | ||
|- | |- | ||
| Temperature / Humidity || SHT4x || | | Temperature / Humidity || SHT4x || | ||
Latest revision as of 21:17, 8 June 2026
Introduction
The bcMeter is a source-available optical absorption photometer designed to measure Black Carbon (BC) aerosols — commonly known as soot — in real-time. The design is freely available for private, educational and research use (CC BY-NC 4.0); assembled instruments are offered on request. Whether you are monitoring ambient air quality in your neighborhood or measuring direct emissions from wood stoves, this device provides scientific-grade data at a fraction of the cost of reference instruments.
The device operates "headless" — it has no built-in screen. Instead, it hosts its own website that you can access from any smartphone or computer connected to the same network.
The software is source-available — freely available for private, educational and research use (CC BY-NC 4.0): github.com/dahljo/bcmeter-pi
Device Types
- bcMeter (DIY) — The source-available, self-build version. Runs on a Raspberry Pi using the source-available PCB design, freely available for private, educational and research use (CC BY-NC 4.0). Build your own from the source-available design files and the Wiki (nothing is sold).
- bcMeter Kit — Assembled-instrument PCB plus components for self-assembly and 3D printing. Available on request.
- bcMeter Complete — Fully assembled, ready-to-use instrument on a compact platform that starts in seconds and updates over the air, with no microSD card or Linux system to maintain. Available on request.
- eBcMeter — Emission measurement instrument for direct source sampling from wood-burning stoves and similar combustion sources. Uses microgram (µg) units instead of nanogram (ng). Available on request.
How Does It Work?
- Polluted air is drawn through filter paper by a pump
- The filter paper absorbs black carbon (BC) particles
- An LED shining at 880 nm passes through the filter; a sensor measures the attenuation (reduction in light intensity)
- A separate reference channel monitors the same LED through a clean portion of the filter, compensating for environmental changes
- The attenuation is converted to BC concentration (ng/m³) using Beer-Lambert law
- Data is saved as CSV and displayed in real-time on the web interface
Multi-wavelength (in development): Additional 520 nm and 370 nm channels for source apportionment via the Ångström Exponent (AAE) are in development and not available in shipped hardware. Current devices measure at 880 nm only.
Sensors & Capabilities
Core
| Measurement | Sensor / Method | Notes |
|---|---|---|
| Black Carbon (BC) | Optical absorption at 880 nm | Primary measurement |
| Temperature / Humidity | SHT4x | |
| Airflow | Omron D6F differential pressure | Pump flow rate |
Optional Hardware
| Measurement | Sensor / Method | Notes |
|---|---|---|
| Temperature / Humidity / Pressure | BME280 | Barometric altitude |
| PM2.5 / PM10 | Sensirion SPS30 | Particulate matter |
| GPS | AT6668 UART | Position, altitude, speed |
| 4G Connectivity | SIM7080G LTE-M modem | Remote data upload |