Figure 1. Block Diagram of the Proposed System (Greenhouse Climate Control and Monitoring System)
The continuous economic growth increases the demand on yield. The main objective of this work is to design a simple, easy to install, microcontroller - based circuit (MSP430) to monitor and record the values of temperature, humidity, moisture, pH (hydrogen-ion concentration) of the greenhouse environment that are continuously modified and controlled in order to optimize them to achieve maximum plant growth yield. The controller communicates with the sensor modules in real-time in order to control the climatic variables like temperature, humidity, soil moisture, and pH efficiently inside a greenhouse by actuating fan (acts as cooler), heater, and water pumps according to the necessary conditions of crops and the greenhouse environment. The changes in the climatic conditions and actions performed are immediately reported to the end user using Internet of Things (IOT). It is used to view the status of the entire greenhouse system anywhere in the world. Thus the proposed system is economical, portable and a low maintenance solution for greenhouse applications, especially in rural areas for small scale agriculturists and also in cities where agriculture is impossible.
As we know that, India is a developing country and the major part of our GDP growth rate belongs to agriculture alone. So, it is said that agriculture is the backbone of India and climatic conditions are called the lifeline [2]. So, agriculture in India has been the most important priority in the economic development since independence. The paper describes the greenhouse climate control and monitoring system using MSP430 [5] with several sensors and IoT. The motivation for this work came from the countries where economy is based on agriculture and the climatic conditions lead to uneven biological diversity. As appropriate environmental conditions are necessary for optimum plant growth and due to uneven climatic conditions, the yield of the crops gets reduced. So several parameters of the environment are monitored and controlled and all the indications would be sent to the respective owner of the form accordingly using IoT. So the owner of the agricultural field can check the status of the greenhouse environment anywhere from the world. The Ethernet shield helps to connect to the internet.
The atmospheric conditions in India changes widely which in turn affects the quality of the plants grown using normal agricultural practices. This also leads to the loss of income to the agriculturists.
Thus the need for the greenhouse environment increased where any plants can be grown at anytime, but it is necessary to monitor and control the parameters inside the greenhouse. The temperature, humidity, soil moisture, and fertilizer are the important parameters that determine the quality of the plant yield.
Thus the controlling and monitoring of all the above mentioned parameters inside the greenhouse using wireless sensor networks with low cost and optimum power consumption and to track the changes anywhere in the world using IoT is the main objective of the proposed system.
A greenhouse system provides high shelter and protects plants from harsh environment and several other external interferences. It allows plants to grow under an optimum condition which maximizes the growth potential of the plants. The existing system only allow for the controlling of climate variables, such as temperature, humidity, CO2 , light, soil moisture, soil temperature, but the important parameter of nutrient supplement to the plants inside greenhouse is not in existence [1].
According to the characteristics of small and mediumsized greenhouse environmental monitoring, a solution to remote greenhouse environmental monitoring is available which is based on GSM technology and RF. It shows that the system is stable, reliable, and it is able to achieve real-time monitoring of green house environment.
But not all the parameters are measured inside the greenhouse environment. The proposed idea brings solution to it where additionally pH of the soil is measured and according to the changes in the values nutrients are supplied to the plant. It reduces the man power and also increases the yield of the plant.
Since GSM [8] is an outdated technology as only message alerts can be sent, we are moving forward to machine to machine language, Internet of Things (IoT).
After setting up a greenhouse environment, the above mentioned sensors in the block diagram are used to measure different parameters of the greenhouse system so that the analysis can be made accordingly.
The method of this proposed system includes wireless sensors [1] to collect the data and communicate with the microcontroller. Based on the information collected from the sensors, the controller takes decisions and perform appropriate actions. Wired communication is replaced by wireless communication to avoid complexity and controlling can be done anywhere from the world. Internet of Things being the trending technology where the data can be monitored anywhere from the world, all the data from the sensors are collected and the microcontroller is connected to the Ethernet shield to make the data available online and represented as a graph to monitor the parameters anywhere from the world. Figure 1 shows the block diagram of this proposed system.
Figure 1. Block Diagram of the Proposed System (Greenhouse Climate Control and Monitoring System)
The temperature of the greenhouse environment is measured using temperature sensor (Figure 2) [7] continuously. A threshold temperature value for a specific plant should be specified by end user. Once the temperature of the environment becomes greater than the threshold value, the respective relay will be energized to turn on the fan and when the temperature decreases automatically, the fan will be turned off by getting a control signal from microcontroller [6].
Figure 2. Temperature Sensor-LM35 (Typically, a Thermocouple that provides Temperature Measurement through an Electrical Signal)
The humidity of the greenhouse environment is measured using humidity sensor (Figure 3) [7], which is placed at the roof of the glass shield. A threshold humidity value for a specific plant should be specified by end user. Once the humidity of the environment becomes greater than the threshold value, the respective relay will be energized to turn on the motor and when the humidity decreases, automatically the motor will be turned off by getting a control signal from microcontroller.
Figure 3. Humidity Sensor-DHT11 (Senses, Measures and Reports the Relative Humidity of the Greenhouse Environment)
The moisture of the soil is sensed using the moisture sensor (Figure 4) [7], which is placed inside the soil. Soil absorbs water based on the moisture content of the soil. A threshold moisture level for the soil should be specified by the end user. Once the moisture of the soil becomes lesser than the threshold value, the respective relay will be energized to turn on the motor and when it increases automatically, the motor will be turned off by getting control signals from microcontroller [4].
Figure 4. Moisture Sensor-YL69 (Measures the Quantity of Water Contained in a Material, such as Soil on a Volumetric or Gravimetric Basis)
The pH of the soil is measured using a pH sensor (Figure 5) [7]. The hydrogen concentration of an element is measured using pH. The value of pH is different for acidic, basic, and neutral elements. When a solution is neutral, the value will be 7, the voltage value indicated will be zero. When the value is above 7, the element is acidic and the voltage value will be positive. When the value is below 7, the element is basic and the voltage value will be negative. As the pH decreases below the threshold value, the motor will be turned on to supply the nutrients to the soil automatically and when the pH value increases beyond the threshold value, the motor will be turned off by getting control signals from microcontroller [4].
Figure 5. pH Sensor (Measures the Hydrogen-ion Concentration (or pH) in a Solution, Indicating its Acidity or Alkalinity)
Many companies now are ready to enable their IoT (Internet of Things) ideas. As a result, we hear about new ideas and solutions that are already solving business ch allenges with M2M (Machine to Machine ) communication. Agriculture IoT is becoming one of the fastest growing fields within the IoT [5]. Today more than ever, farmers have to more effectively utilize and conserve their resources. That's where the need for data comes in and M2M communication has made the ongoing collection of the information easy.
In this work, all the collected data from the microcontroller can be viewed online through an Ethernet cable. This monitoring can be done through any devices like mobile, tab, laptops, and PCs.
As all the parameters are controlled and monitored automatically, the crops inside the greenhouse can be cultivated at any climatic conditions and due to the appropriate climate is maintained inside the greenhouse, all type of crops can be grown effectively irrespective of the natural climatic conditions.
Since the greenhouse environment is fully shielded and highly protected from fungus and pest attacks as in Figure 6, the crops gain efficient growth and yield increases so all the products will be available in market at any time.
Figure 6. Final Setup of the Proposed System
Since all the operations are automated inside the greenhouse, the requirements of human operators can be replaced and reduces the total amount of time required for the crops to grow.
The use of easily available components reduces the manufacturing and maintenance costs. The design is quite flexible as the software can be changed any time as it acts as a user friendly system. The use of wireless communication [1] avoids inevitable problems faced with wired communication like mass construction, installation, and maintenance difficulties. The usage of low power equipments makes the proposed system power efficient and saves energy. The analysis of several parameters inside the greenhouse environment is represented in Figures 7, 8 and 9.
Figure 7. Temperature Analysis
Figure 8. Graph of Soil Moisture Level
Figure 9. Humidity Level Measured for a day
Thus, this idea helps to avoid over-irrigation, underirrigation and top soil erosion as the water is supplied only based on the moisture level of the soil and also reduces the wastage of nutrients leading it to be a cost effective system. The main advantage is that the system's action can be changed according to the crops, weather conditions, soil, and also the flexibility of the farmer. By implementing this system, all agricultural lands can be controlled and monitored for the efficient yield. Thus, this system is cheaper and efficient when compared to all other greenhouse agricultural systems.
For the forthcoming days, the authors have planned to both control and monitor the greenhouse environment using IoT. Thus, the changes inside the greenhouse can be done from any other part of the world if needed.