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Project Karaburan
Monitoring water quality
Status Initializing
Contact bertrik
Last Update 2024-04-29



  • air quality sensors
    • ammonia
    • NOx
  • water chemical analysis
    • nitrates
    • ammonia
    • dissolved oxygen
    • sulfide/sulfate
    • phosphates?
    • salinity (chlorides?)
  • water physical analysis
    • temperature
    • clarity/turbidity -> investigate standard ways of measuring/expressing this
    • conductivity/total dissolved solids
    • water properties by light reflection, hyperspectral/polarity
    • depth?
  • boat control
    • trajectory -> steering
    • idea: interface with the remote control, not with the boat
    • idea: find a boat with easily hackable remote control protocol
    • idea: can we get sensor data over this link too, e.g. GPS?
  • camera control
  • post-processing
    • data presentation
      • video/photo stitching
      • time lapse view
      • map view of properties
  • use cases
    • verify with domain experts, how to engage?
    • slootview, under/above water
    • minimum viable prototype
    • high-res measurement by location, by time
  • materials
    • boat selection
    • processing platform selection
    • communication platform selection

Air quality sensors

Nitrogen compounds in air

According to https://www.rivm.nl/stikstof/monitoren-advies-onderzoek/overzicht-stikstofmetingen/metingen-stikstof-in-de-lucht average (typical?) values of

  • Ammonia (NH3): 6.7 ug/m3 (9.6 ppb)
  • NOx: 27.3 ug/m3
  • NO2: 18.6 ug/m3 (9.9 ppb)

(ppb-conversion using https://www.breeze-technologies.de/blog/air-pollution-how-to-convert-between-mgm3-%C2%B5gm3-ppm-ppb/ )

RIVM report on inexpensive nitrogen-in-air sensors: https://www.samenmeten.nl/sensoren-voor-no2 Conclusion: most sensors are not sensitive enough to be used in typical outdoor conditions, with perhaps one exception: alphasense NO2-B43F

Water physical analysis

Turbidity / clarity

See https://en.wikipedia.org/wiki/Turbidity

Aliexpress sensor TS-300B: https://nl.aliexpress.com/item/1005006732956937.html Has a range 0 ~ 1000 ± 30 NTU

Order of magnitude for turbidity:

  • Drinking water upper limit: 4 NTU (European turbidity standard for drinking water)
  • Ambient water: 10-150 NTU. The US state of Washington use a "background" value of 50 NTU as reference.

(see https://en.wikipedia.org/wiki/Turbidity#Standards_and_test_methods )

So the Aliexpress sensor is mostly suited for very dirty water.

Boat control

Typically the wireless link looks like this:

  • 2.4 GHz working frequency
  • 500m range

Interesting links:

Use cases


Useful distinction, typically used in documents/guidelines:

  • chemical quality, what substances are present in the water?
  • biological / ecology quality, what kind of living organisms live in the water?

Reeuwijkse plassen


potential applications:

  • slootview, inspect water sides over time
  • underwater camera: detect invasive cray fish
  • sample water properties at high spatial resolution, high time resolution
  • early detection of indicators for cyanobacteria: temperature and nutrients