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USING ELECTRONIC TECHNOLOGY TO REMOTELY MONITOR
CONDITIONS, AND DISPLAY DATA ON INTERNET IN REAL-TIME
John Nowatzki
Department of Agricultural and Biosystems Engineering
North Dakota State University
Fargo, North Dakota
Roger Ashley
Dickinson Research Extension Center
North Dakota State University
Dickinson, North Dakota
ABSTRACT
This session describes the use of electronic equipment to monitor soil temperature
and moisture, air temperature, relative humidity, wind speed, solar radiation, leaf
wetness, and rainfall. Presenter will explain how to use the equipment to monitor
conditions, transfer the data, and display the information in real-time on the
Internet. Potential applications include: 1) provide real-time information to crop
producers for use in crop management decisions; 2) remotely monitor equipment
operation; and 3) record remote conditions to calculate evapotranspiration. The
presenter uses the technology to remotely monitor soil and ambient conditions
using electronic sensors and data loggers, and solar charged cellular modems. The
data is transferred to computers using cellular and ftp technology, allowing for
near real-time display on the Internet. The sensors and data loggers are Onset
products: http://www.onsetcomp.com/index.php. The modems and solar chargers
are
SolarStream
from
Upward
Innovations:
http://www.upwardinnovations.com/upward/home.html. The data is displayed on
the Internet by computers and servers operated by Data Garrison:
https://datagarrison.com. The data is also display the real-time data from the
remote sites on the North Dakota State University Extension Agricultural and
Biosystems
Engineering
Web
site
at:
http://www.ag.ndsu.edu/agmachinery/wirelesstechnology.
Keywords:
remote monitoring, technology, electronic, cellular
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INTRODUCTION
This project is designed to demonstrate available technology capable of
sensing soil and ambient field conditions remotely, and displaying the data on the
Internet in near real-time. The authors collaborated with other North Dakota State
University research and extension faculty to monitor conditions in various
projects in order to demonstrate these technologies with real data. A residue
management project involved monitoring rainfall, soil temperature, soil moisture,
rainfall, and wind speed in three wheat stubble heights in three locations across
North Dakota. A tile drain demonstration site, involved monitoring rainfall, soil
temperature, and soil moisture, comparing drained and non-drained conditions in
the same field. A third project involved monitoring soil and ambient conditions in
soybean tillage demonstration sites.
MONITORING EQUIPMENT
Data Loggers and Sensors
Each monitoring site is equipped with a battery-powered HOBO Weather
Station Data Logger and Hobo Smart Sensors that provide a digital readout. The
sensors are connected to the data logger with a cable, thus limiting the sensing
distance away from the data logger. (Figure 1) Cable extensions are available to
extend the distance. The data accuracies are different for each sensor type, and are
available on the Onset Corporation Web site.
The Weather Station Data Loggers can accept up to 12 plug-and-play smart
sensors, with adapters to accept ten additional sensors. The data can be offloaded
directly to a modem, or to a computer using a USB cable. The data logger is
powered by four AAA batteries. The use of lithium batteries facilitates operation
in cold temperatures.
Fig. 1. Cellular Modem with Solar Charger, Data Logger, and Rain Gauge.
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Sensor Issues
The sensors generally function properly, and are warranted by the
manufacturer for one year. The smart sensor housing need to be protected from
rain and standing water, either by adding silicone sealer where the cables enter
and leave the sensor housing, or wrapping the entire smart sensor in waterproof
material. The sensor cables may need to be protected from damage from animals
or other physical harm.
All sensors withstand weather conditions typical of the Northern Great Plains,
although soil the moisture sensors do not function when the soil is frozen.
COMMUNICATION TECHNOLOGY
Cellular Modems
Each remote site is equipped with a six volt, battery powered, cellular modem,
and a solar charger to maintain power for the modem. (Figure 2) The data is
transferred from the logger to the modem by a cable connection. The cellular
modems were purchased from Upward Innovations Company.
The data is sensed at various time intervals at each site and transferred to a
remote computer via cellular communication technology every six hours.
Electronic commands can be sent to the data loggers using the cellular
communications.
Fig. 2. Cellular Modem with Solar Charger
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Cellular Service
Upward Innovations modems use various cellular services based on local
available coverage. The services in projects described in this article used Sprint
Cellular service in five sites. One site uses Iridium Satellite cellphone service
because of a lack of Sprint coverage. A minimum cellular subscription service is
required at each site.
Upward Innovations provides the cellular service subscriptions. They also
provide a no-cost, secure Web site to store and display the data from each remote
monitoring site. (Figure 3
Fig. 3. Secure Web site provided by Upward Innovations.
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Communication Issues
This project has experienced few communication problems, and those are
serviced and resolved by Upward Innovations technical service personnel. During
winter months when there are fewer hours of sunlight available to keep the
modem batteries charged we decreased the data transmission rate to conserve
battery power.
DISPLAYING DATA ON INTERNET
Transferring Data to Server Computer
The Upward Innovations Web site service includes FTP service to transfer the
data in digital text format to server computers connected to the Internet. The FTP
service is programmed to transfer the digital text data from the Upward
Innovations computer to the North Dakota State University computer server each
time it is received from the remote data logging sites.
Serving Data on the Internet
The text files are displayed on the Internet using flash and JavaScript
(HTML5) freely available on the Internet from amCharts Company. (Figure 4)
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Air Temperature
Average 22°F
Short Stubble Temperature
Average 27°F
Ridge Tilled Temperature
Average 25°F
Medium Stubble Temperature
Average 29°F
Chisel Plowed Temperature
Average 28°F
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10
0
Average Temperatures
Cass County
Dec. 1 - March 1
2011-2012
-10
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-20
Fig. 4. Data displayed on Internet using amCharts Company charts.
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Internet Display Issues
Each sensor at the remote data logging sites is identified by a serial number.
The text file generated by the data logger records the data from each sensor from
smaller serial number to larger numbers. When sensors are replaced the new
sensor has a different serial number and is therefore displayed in a different
location in the text file. When the digital text file arrives at the server computer,
the amChart server software is programmed to read the text file data by increasing
serial numbers. Therefore, each time sensors are changed at the remote
monitoring site, the server software requires some minor reprogramming as well.
COSTS
Total equipment costs at each remote monitoring site in this project varies
from approximately $1,500 to $2,500, based on the type and number of sensors at
each location. The annual cellular subscription costs are $180 for each site using
Sprint services and $360 for the site using Iridium services.
SUMMARY
Real-time monitoring of soil and ambient conditions at the remote sites
described in this article are displayed on the Internet at
http://www.ageng.ndsu.nodak.edu/farmmonitor/index.php.
The
technology
described can be used to: 1) gather research data to support teaching and
Extension publications; 2) provide real-time information to crop producers for use
in crop management decisions; 3) demonstrate remote monitoring technologies
for Extension audiences. The soil and ambient conditions are monitored using
electronic sensors and data loggers. The data is transferred to computers using
cellular and ftp technology, allowing for near real-time display on the Internet.
Conditions monitored include soil temperature and moisture, air temperature,
relative humidity, wind speed, solar radiation, leaf wetness, and rainfall in six
locations.
This technology could be used in various applications including crop
production conditions where fields are in remote locations or distant from
management personnel.
REFERENCES
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AmCharts. 2012. AmCharts Web site: Available at:
http://www.amcharts.com/about/. Accessed 25 April 2012.
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Data Garrison. 2012. Data Garrison Web site: Available at:
https://datagarrison.com/. Accessed 25 April 2012.
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