Automated Irrigation System Using WSN
Abstract: The project develops an automated irrigation system to improve freshwater utilization. Agriculture uses a huge percentage of the available usable freshwater, and with increasing population growth over time, the freshwater is more likely to become a major problem in obtaining. To help mitigate the risk of lacking freshwater wastage, the project develops a solution to the immediate problem of monitoring and effectively utilizing the available resources. It does so through a smart system that monitors the soil moisture using set-out sensors and transmits this data to a central server with then dispatches it to actuators for implementation—the sensor involved in the measurements are the soil humidity sensor, light sensor, and temperature sensor. The use of an automatic system is cost-saving and conserves water that could otherwise be wasted; more and more technologies have been developed in the past to improve the amount of water wastage witnessed in the irrigation systems. Resulting from these technologies, there has been more water-saving and better results in irrigation management.
I. Introduction
Agriculture viable activities consume a good percentage of the available usable freshwater, about 85% [1] of the available water. It is also estimated that it might grow in the near future as the population is on the rise and the demand for more agricultural activities to cope with the people’s needs. The increase in the population will put more pressure on the already highly used resources. Therefore, there is a need to develop more efficient and better methods to manage the scarce resources and cope with the future needs of agricultural water.
In the past, there have been more systems developed to deal with the issue of water limitation. [2] The systems are developed to save water in the agriculture area in various crops and farms. For example, there are systems that monitor the canopy temperature distribution in plants and schedule irrigations. They use the water stress index to determine the water level and when there is a need for irrigation. The canopy temperatures were measure using infrared, temperature, atmospheric temperatures, and vapor pressure. An example of crops where this type of method was used is the growth of the broccoli plant.
Another method that can be used to automate irrigation systems is by use of volumetric water levels using dielectric moisture sensors wired to actuators to control the water soil content rather than scheduled irrigation. The systems use a threshold point to determine when to open the irrigation valves and drip the water or sprinkle it.
Infrared thermometers can also be used to measure the temperatures and trigger the opening of valves when a threshold temperature is set; this kind of sensor has been used to irrigate crops such as cotton in large fields. The infrared thermometers have increased the efficient use of water than the traditional methods of irrigation [2].
Estimate Plant Evapotranspiration or the ET can also be utilized; they are affected by parameters such as the solar radiation, temperature, crop factor, speed of the wind, and plant density. An ET combined with a tensiometer has also seen recent development in various farms to improve on water saving. For instance, papaya in Florida uses a combination of ET and tensiometer to save up to 42% of the water.
Electromagnetic sensors which can measure the soil moisture content can also be essential in helping to save the scarce resource of fresh water. An electromagnetic sensor saves up to 53% [1] of the water compared to the traditional methods such as sprinkling in the pasture. A combination of evaporimeter can boost the saving figures highly.
The microcontroller-based WSN technology can improve the already existing methods and techniques. Data can be monitored remotely over a wide range of areas and from different applications considering areas that have challenges accessing, such as the bad terrain areas.
II. Literature Review
The agricultural yields over time have been decreasing day by day, and the application of technology to this field to help improve the yield plays a major role.
Many water-saving systems have been developed to advance technology in the agriculture field. Most of them have been automated and improves on the scheduled irrigation methods. Some Florida farms have utilized the ET calculated from historical weather information to determine controller and actuator actions.
Some of the existing systems include:
- Rice crop monitoring using GPRS and wireless sensor for the improved water use for irrigation.
- Wireless Sensor and Remote Based Systems using ZigBee.
- Embedded systems for automatic drip irrigation.
- ARM-based field observing and monitoring system.
- GSM-based systems irrigation systems.
- Remote and sensing of a control-based wireless network.
Research by Chandan Kumar and Behra Pramitee presents a solution with a prototype that can be utilized for full automation of irrigation where sensors were utilized from different farms. Various sensors utilized wireless networks for communication and data analysis. ATMEGA microcontroller -328 microcontroller, an Arduino UNO board. The communication was interconnected using RASPBERRY-Pi, which correspondences to the internet and relays to the controllers. The main idea of the paper was to control the motors remotely and automatically by using the data gotten from the soil moisture sensors and temperature sensors; the information is then used to determine the direction of motor sprinklers and the amount of time.
The authors A. N. Arvindan and Keerthika used an android smartphone to remotely control Arduino based irrigation system that was easy to use and implement. The design utilizes the moisture sensor data and temperature data that is compared to the threshold point and then used to determine the irrigation time and schedule. Data obtained from the sensors are fed into an Arduino Uno processor that is linked to an HC-05 module to an Android phone. The phone can then easily manipulate the data and control the irrigation system. The link to the smartphone is easily used in real-time.
- M Aileni researches mobile application in healthcare. The application utilizes data on humidity and temperature sensors to make a decision. Their research is based on cloud SaaS, which is a cloud as a service. Data is sent to cloud storage which is a server that enables data analysis by doctors and caregivers to take advantage of and determine the kind of medicine to give.
Research has also been done by P. Archana and R. Priya that comes up with a technique that uses humidity and moisture sensors, and the data is used to determine the water that is fed to the roots of the plants.
III. Design and Methodology
The planned system intends to analyze the existing and the nature of the problem facing the in relation to the study plan, analysis of already used unique and associated technologies that have been used in the systems, development of guide specifications of the program, and decision and implementation of the project, accelerometer use to connect the embedded system with the sensors and process control computer, development and testing of the system to improve the system performance[3].
The block diagram below shows the arrangement of the systems to be implemented [2].
Fig 1. The circuit arrangement of the system.
The above diagram shows the circuit arrangement of the proposed implementation of the system. The first part is the sensors involved, and the other part is the LCD panel that displays the monitoring of data such as water supply and motors. [5] The required components are the Arduino processor, motor, different sensors, and the display (LCD).
Components specification include:
- Temperature Sensor (LM35)
The sensors that are used to measure the temperature in this project are the field LM35. [3] They are a precision integrated-circuit sensor for temperatures, the voltage from the sensors is linearly related to the temperatures. The sensor does not need any other input to manipulate the data and be effective [2]. It is already calibrated to cover a range of -55 to +150 Celsius. It draws 60 micro Amperes from the mains, and it has an effective heating process of approximately 0.1 Celsius.
- Humidity Sensor (DHT11)
Sensors regularly report the relative humidity in the air; it is also known as the hygrometer. It measures the temperature and moisture in the air. The sensors are meant to measure the air warmth. The most commonly used sensor is the capacitive measurement sensor which uses the electrical capacitance or the electrical field created between conductors that measure the moisture in the air, and any unique difference in the humidity in the air causes voltage stress between the plates. The voltage is then converted to digital signals to be displayed on LCDs.
Arduino systems can be combined to measure the soil PH too to determine the soil acidity and be used to make a decision on the crop type. The system is helpful for the people that travel often and are not constantly on the farm to manage them or schedule irrigation. The comparison of data is made easy by the use of Arduino.
Agriculture plays an important role in country development and feeding of its citizens to enable easy and rapid development to support the economy and run it smoothly.
- Soil moisture sensor
Soil water content or the amount of moisture in it can be easily read by use of soil sampling or other soil water sensing and monitoring methods such as the ones used in irrigation. The most used sensors are dielectric. They determine the soil water content by determining the soil bulk permittivity of the dielectric constant. An electromagnetic signal is sent through the soil, and the emerging pulse is measured for any discrepancies. The soil permittivity is a combination of different minerals, and the water permittivity is large than any other component in the soil, and therefore the dielectric constant will be majorly determined by the presence of water in the soil.
- Arduino Micro-controller.
Arduino is open-source hardware and software that is easy to use and can be manipulated easily to achieve the intended use. It mainly works by remote activation to trigger a motor or something that is supposed to be controlled. It can be powered externally or through a USB.
- Motor
The current requirement for the project is low, and the choice of motors should be able to use low current in their working [4]. Therefore, the choice of motors to be should be able to work smoothly and efficiently under low current. The motor chosen is a counter-clockwise rotating motor with the following specifications.
2-12 voltage
The nominal volt is 12 volts
The no-load speed is 5800 rpm
The current when there is no load is 0.22 A
The speed that is efficient to be used is 4906 rpm
Efficient current for operating is 0.17 to 0.23 A
Efficient torque for operating is 21.1
The diameter is to be 24.4mm
The shaft diameter is 10.5 mm
The shaft length is 32.4 mm
The end play is 0.05 mm
The operating temperature is –
- ATMEGA 328P Micro controller
It has a low-power CMOS 8-bit microcontroller that is majorly based on the AVR. The controller will be used to control the actuators used in the irrigation.
IV. Results and Discussions
There are software requirements for the system to work correctly. One of them is the Arduino IDE which is open-sourced and can be easily master to manipulate and get the desired results. The software was downloaded from the Arduino main site. The second requirement is how to use the Arduino IDE tools step by step.
-Get the Arduino board and a data transmitting USB cable.
-Download and set up the Arduino environment
-Connecting the board.
-Drivers installation.
-Launching the application.
-Selecting the board.
-Selecting serial port.
Embedded C is another requirement of software that is crucial to the system to work. Embedded C is an extension of the C program and is used for implementing applications.
The project works together as an integrated system of blocks in order to get the final results; these building blocks include the acquisition block, microcontroller block, monitoring block, and automated functioning block.
- Acquisition section
The section is made of a moisture sensor that is intended to measure the soil water content. The sensors work by reading a high signal when the soil is wet and sending a low signal when the soil is dry; the data is uploaded to a server.
- Microcontroller section
This is the brain of the system and is where the Arduino microcontroller is found. The information gathered from all the sensors in the field is managed by the microcontroller and used to make the decisions.
- The monitoring sections
The monitoring section is where the results that have been processed by the microcontroller are displayed; it is made up of an LCD display. The water level in the soil is displayed here as a percentage and interpreted. When the percentage happens to be down, it will mean that the soil is dry, and the opposite is true.
- Automated section
It is made up of actuators that make the irrigation happen; they are motors that rotate according to the commands they receive from the microcontrollers. The watering function is executed here. Apart from the motors, there are also pumps in this section to increase the pressure of the water; they are also controlled by the microcontrollers. It is normally switched using a relay that relies on electromagnetics. The switch is triggered from the microcontroller and receives a command from it.
V. Conclusions
The major application of this project is to be used for farming in areas that intend to save water or with limited water for crop irrigation and prevent wastage of water that is fresh and can be utilized for other purposes. Water is scarce and needs to be used sparingly when possible, especially in regions with less or inadequate water; this technology intends to help protect the scarce water and prevent wastage. The papers herein propose an automated system that is an improvement to the already existing technologies in order to optimize agricultural production. The system suggested here has been tested and found to function within the normal range. The future expected improvement would be to determine the moisture requirement of different crops and then release only the required amount of water to these plants for effective use of freshwaters. Work on the suggested system presented here should continue to see more improvements on the type of sensors involved and the accuracy that they have. There is hope that in the future, robotics might be employed to change the direction of the sprinklers to face exactly the side of the root that requires a certain amount of water and change the direction when the need arises.
