DESIGN AND IMPLEMENTATION OF A SOIL MOISTURE DETECTOR WITH AUTOMATIC SMS NOTIFICATION SYSTEM
1.1 Background to the study
Through the ages agriculture production systems have benefited from the incorporation of technological advances primarily developed for other industries. The industrial age brought mechanization and synthesized fertilizers, the technological age offered genetic engineering and now the information age brings the potential for Precision Agriculture (Rasher, 2001). Precision agriculture (PA) , satellite farming or Site Specific Crop Management (SSCM) can be defined as a set of technologies that have helped propel agriculture into the computerized information-based world, and is designed to help farmers get greater control over the management of farm operations (Gandonou, 2005). One of the key technologies of precision agriculture is the control and accurate measurement of the soil moisture. For decades, the subject of soil moisture has been of great interest in agricultural system. Prior to advancement in agriculture, farmer has picked up and felt a handful of soil to determine the best time to plow his fields and equally to manually determine the amount of moisture content of the soil. Soil moisture measurement ranges from the method of feeling the soil to the use of complicated electronic equipment using radioactive substances. Such method includes the use of soil sensor. Since the inception of precision agriculture, soil sensors have been used to measure the soil moisture level. The soil moisture sensors measure the volumetric water content of the soil by using electrical resistance, dielectric constant, etc. The farmer uses the information obtained from the soil moisture sensor to make
adequate and accurate decisions on how and when to irrigate or plough his farmland.
Today, technological progress in communication, along with the information revolution has reduced the amount of work done by the farmer and has since then increased yield. Precision agricultural technologies, such as Global Positioning Systems (GPS), Geographic Information Systems (GIS), remote sensing, yield monitors, and guidance systems for variable rate application, made it possible to manage within-field variation on large scales. The GIS is a software application that is designed to provide the tools to manipulate and display spatial data (Blackmore, 1993). These technologies allow detection and/or characterization of an object, series of objects, or the landscape without having the sensor in physical contact (Viacheslav et al., 2003). General Packet Radio System (GPRS) is a third-generation step toward internet access. GPRS is also known as Global System Mobile Communication Internet Protocol (GSM-IP). GSM-IP keeps the users of this system online, allows to make voice calls, and access internet on-the-go. Even Time Division Multiple Access (TDMA) users benefit from this system as it provides packet radio access. GPRS also permits the network operators to execute an Internet Protocol (IP) based core architecture for integrated voice and data applications that will continue to be used and expanded for 3G services. GPRS supersedes the wired connections, as this system has simplified access to the packet data networks like the internet. The packet radio principle is employed by GPRS to transport user data packets in a structure way between GSM mobile stations and external packet data networks. These packets can be directly routed to the packet switched networks from the GPRS mobile stations. In the current versions of GPRS, networks based on the Internet Protocol
(IP) like the global internet or private/corporate intranets and X.25 networks are supported.
Listed are some of the key features of GPRS wireless network:
i. The always online feature - Removes the dial-up process, making applications only one click away.
ii. An upgrade to existing systems - Operators do not have to replace their equipment; rather, GPRS is added on top of the existing infrastructure.
iii. An integral part of 3G systems - GPRS is the packet data core network for 3G systems Enhanced Data GSM Environment (EDGE) and Wideband Code Division Multiple Access (WCDMA).
Remote sensing uses aerial or satellite imaging to sense crop vegetation and identify crop stresses and injuries or pest infestation. As an application of the new information technology adapted to agriculture, the essence of this technology is based upon the availability of data and the use of this data in the decision-making process (Gandonou, 2005).
Data collected from soil sampling, yield monitoring, crop scouting, remote sensing, and satellite imaging are used to create maps. For example, yield map data can reveal a low yielding area. Remote sensing imaging techniques can highlight crop stress, disease and other field or crop characteristics. The availability of historical data combined with multiple layers of information for a farmer engaged in PA improves the quality of inputs recommendations and management decisions. The effectiveness of the decision making however, will depend on a quick and accurate analysis of temporal and spatial data. In this context, precision farming technologies are widely known to assist growers in making informed decisions. By helping in making informed management
decisions, PA could be used by producers as an effective management and risk management tool. A moisture detector is an electronic device that is designed to detect the presence of water and provide an alert in time to allow the prevention of water damage. It is used to measure the percentage of water in a given substance. The information obtained can be used to determine if the material is ready for use, unexpectedly wet or dry, or otherwise in need of further inspection.
Soil moisture content is one of the most critical soil components to plant growth and land management, especially in dry-land. Therefore measuring soil moisture is important for agricultural applications to help farmers manage their irrigation systems more efficiently. Knowing the exact soil moisture conditions on their fields, not only are farmers able to generally use less water to grow a crop, they are also able to increase yields and the quality of the crop by improved management of soil moisture during critical plant growth stages.
1.2 Statement of Problem
Before the advancement in agriculture, detecting and monitoring soil moisture level in order to alert the farmer on when to irrigate his farmland is somehow difficult. While determining soil moisture is paramount in agriculture, it will be more appropriate if this can be done with little or no human intervention so as to make adequate and accurate decisions. The previous means of relying on human perfection in determining the soil moisture has not been effective. The need to develop a system that will be able to determine the soil moisture level and send the same (gathered data) to the farmer through SMS notification without human intervention is necessary. Hence this study.
1.3 Aim of the project
The aim of this study is to design and implement a soil moisture detector with an automatic SMS notification system using Arduino micro-controller and GSM SIM900 GPRS module.
1.4 Objectives of the project
The objectives of this study are as listed:
(a) Design soil moisture detector and automatic SMS notification system model.
(b) Implement the design in (a).
(c) Evaluate the effectiveness of the implemented design in (b).
1.5 Methodology Overview
Through the following methodologies, the goals of this project were achieved:
i. Use Fritzing electronics modeling tool in designing the automation and monitoring system that uses high sensitive soil moisture sensor to detect moisture level.
ii. Insert the two soil sensor probes into the soil which forms a variable resistor and connects to Arduino microcontroller via its A0 port.
iii. Using GSM SIM900 GPRS module, implement transfer of aggregated data in (ii) to a mobile phone.