RSMN Implementation and Calibration

It’s been taken into account the evaluation of the temperature sensors and soil moisture on the market, choosing a type of sensor that meets the needs of the project, and their acquiring the related equipment for testing and calibration laboratory engaged prior installation and integration with existing weather stations, installation, testing and calibration in-situ. It was established the structure (schema - block) for mobile stations, following hardware design, software design, assembly, laboratory testing and in-situ field installation.

RSMN Design - the fixed component

In order to select the most suitable locations, the following criteria and information had been taken into consideration:

  • Existing weather stations locations;
  • Site elevation <300-500 m;
  • Minimal forest, water and localities coverage;
  • Small amount of argil soil;
  • Reduced RFI interference;

All of the 20 proposed station are operational

Coordinates
ID Name Lon Lat
15479 Adamclisi 27.96591288 44.08828906
15489 Alexandria 25.35286364 43.97780601
15197 Barlad 27.64438367 46.2331338
15460 Calarasi 27.3385146 44.20572207
15136 Chisineu Cris 21.54177115 46.51867633
15408 Corugea 28.34225398 44.73444284
15056 Cotnari 26.92545711 47.35829844
15000 Darabani 26.5732519 48.19477108
15083 Dej 23.8989254 47.12795904
15189 Dumbraveni 24.59160604 46.22786185
15080 Oradea 21.89611975 47.03580162
15470 Rosiorii de Vede 24.97871777 44.10711102
15199 Sannicolau Mare 20.60158621 46.07155688
15010 Satu Mare 22.88736848 47.72144328
15425 Slobozia 27.38372843 44.55277587
15265 Tecuci 27.4090074 45.84164072
15090 Iasi 27.62545609 47.16314699
15434 Slatina 24.35445532 44.44211128
15289 Banloc 21.1362639 45.3829027
15412 Bacles 23.11289872 44.4761669

At the existing weather stations location the 5TM probes will be interfaced with the existing automatic weather station data loggers (Vaisala/Logotronic).

Fixed Station Scheme

GIS databases used for mapping

Mobile Station Scheme

The mobile stations are built around the Arduino Uno board fitted with a GSM shield, for communication and powered by a solar panel and battery. One 5TM Decagon sensor is used at a depth of 0-5 cm.

RSMN Design - the mobile component

Is meant to allow for easy reconfiguration of the soil moisture network depending upon the satellite product to be validated. 30 autonomous mobile stations will be deployed in different areas according to the scheme below.

Data-logger for humidity and soil temperature

Within the ASSIMO project, for the automatic measuring of the volumetric soil moisture the Decagon 5TM sensor is used, created by Decagon Devices, which corresponds the criteria.

The 5TM Decagon transducer is a precise instrument for monitoring the volumetric content of water and that of soil temperature. It determines the volumetric soil moisture through measuring the dielectric constant using the capacitive method (Frequency Domain Reflectometry).

The advantages of using the 5TM transducer:

  • It offers two measured dimensions (the volumetric content of water and the soil temperature);
  • Low power consumption, which makes possible its use in battery power systems;
  • The SDI-12 serial interface allows connection with systems built by other companies.

Composition and characteristics:

  • The Olimexino development platform with the 8 bit ATmega328 microprocessor: 32kB flash memory, 2kB RAM memory, 1kb EEPROM memory, MHz clock, 6 analog entries, 16 digital inputs/outputs;
  • The 5TM Decagon intelligent sensor for for soil moisture and temperature, the SDI-12 serial communication;
  • The TMP102 intelligent sensor for temperature, 12C serial communication; • microSD mode cu SPI serial communication;
  • The Arduino GSM mode which uses the Quectel M10 modern radio.

At the existing weather stations location the 5TM probes will be interfaced with the existing automatic weather station data loggers (Vaisala/Logotronic).

The Olimexino328 development platform

The electric scheme of the Data logger for soil moisture and temperature

In the scheme are shown all of the connections between modules and between the transducer and the development platform.

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