OVERVIEW
This chapter deals with the following parts: brief introduction about automatics in agriculture, domestic and foreign researches on automatic watering system models, and additional solutions to the research topic
Automatic systems which comprise automatic components are systems used to control processes happening in the nature and life without direct interference from human beings
Automatic control systems are combination of physical elements which are related to each other and used to monitor, adjust or control other systems
Automatic control systems are very popular nowadays
- Automatic production and assembly lines
- Control machines operating based on programs, computers, robots, etc
1 2 Role of automatics in production
Advancements in mechanization and electrification have led to the evolution and refinement of production tools and equipment Innovations in material technology, along with developments in electronics and information technology, have fostered a thriving environment for automation This progress has significantly benefited society, enhancing efficiency and productivity across various sectors.
The implementation of automation technology in production leads to significant benefits, including reduced production costs, enhanced productivity, and improved working conditions This advancement allows businesses to meet the high demands of modern manufacturing while fostering specialization in production processes As a result, companies can boost their competitiveness and effectively satisfy evolving production requirements.
In the near future, automation will become essential, significantly impacting both production and daily life In industrial settings, it will take over tasks that are hazardous, complex, or require precision, effectively replacing human labor in these areas Additionally, automation will cater to various human needs in everyday life, making it an integral part of our routines.
1 3 Application of automatics technology in watering plants
Vegetation work serves as the foundation of agricultural production and exemplifies modernization in the field By automating all processes involved in agriculture, it is possible to reduce labor requirements and enhance crop yields effectively.
Automatic watering technology has been utilized for years, primarily in developed countries In contrast, developing nations, despite agriculture's significant role in their economies, have not widely adopted this technology However, with foreign assistance, many Southeast Asian countries, including Vietnam, are increasingly implementing automatic watering systems in both daily life and agricultural production.
In today's rapidly advancing world, the significant progress in automation technology, along with breakthroughs in microelectronics and information technology, has made automation feasible across various sectors It is evident that automation has emerged as a prevailing trend in industries worldwide.
1 4 Researches conducted in foreign countries
There have been many researches on automatic watering system in foreign countries so far:
In the early 1980s, the Soviet Union developed an advanced agricultural machine capable of monitoring land moisture, atmospheric temperature, and wind force This innovative device not only assessed environmental conditions but also determined optimal watering methods, utilizing technology to create artificial rain for efficient irrigation.
Droplet, a pioneering robot manufacturer, has launched innovative watering robots that utilize advanced automatic technologies and cloud computing to optimize plant care These robots can autonomously monitor injectors, adjust water volume, and determine watering frequency based on self-calculated schedules derived from input data Capable of watering plants within a 9.14-meter radius, Droplet requires users to input the names of their trees via a connected device The robot then gathers information online to establish the ideal watering parameters for each tree species, while also considering local weather conditions to create an effective watering schedule Additionally, the Israel automatic watering controller offers user-friendly programming, and the installation of this cutting-edge system is straightforward, requiring minimal setup and an input water source to direct the injectors to the necessary locations.
There are two kinds of control: based on watering time and circle:
- Control based on watering time: Systems operate according to real time shown in clocks
- Control based on watering circle: Systems operate according to repeat circles of the time
Time and magnetic valve controllers:
An auto controller is essential for scheduling automatic watering, allowing users to define the operating time, duration, and cessation of water flow Equipped with a rain sensor, this device ensures efficient water management by halting irrigation during rainfall or when atmospheric moisture levels are elevated.
- Magnetic valve: is device which receives and transmits signals from the controller to injectors so that they can operate properly.
The operation of watering systems involves setting a specific watering schedule, during which the controller sends signals to magnetic valves These valves then automatically open to deliver water to the injectors, ensuring efficient irrigation Users have the flexibility to adjust the watering time as needed.
Numerous studies on automatic systems have been conducted in Vietnam, leading to practical applications such as semi-automatic watering systems that enhance productivity and reduce labor costs compared to manual methods Despite these advancements, the current systems still exhibit several shortcomings that require further improvement for optimal performance Additionally, students at technology universities have explored various research topics related to automatic watering systems, but these initiatives also face significant challenges.
The multipurpose automatic watering system, developed by Dr Le Van Luan and MS Le Dinh Hieu from Hue College of Industry, features a temperature sensor and soil moisture sensor designed for use in a poly-greenhouse for flower cultivation, with a control system programmed on PLC-S7.
When the sensors in the poly-greenhouse detect low soil moisture or high atmospheric temperature, they send a signal to the PLC controller This system then automatically manages the water injection process through the installed injectors, ensuring that watering occurs only when necessary and halts once the optimal moisture levels are achieved.
5 minutes after the temperature sensor or the land moisture sensor meets requirements
The multipurpose automatic watering system is product of a very good and realistic idea realistic It was experimented and brought good results
Recent studies have shown that traditional watering systems can be prohibitively expensive for many consumers To address this issue, the author developed an innovative watering system that utilizes a moisture sensor to optimize watering schedules This cost-effective solution is not only easy to manufacture and repair, but it also offers an affordable alternative for those seeking efficient irrigation methods.
CONTROLLER ELEMENTS
Controller design has feature to control close/open auto electrical equipment via temperature and humidity sensors
- Receiver unit including temperature & humidity sensors, a Matrix keypad 4x4
- Processing unit Board Arduino Mega 2560
- Equipment controlling unit using Relay 5VDC to close/ interrupt equipment
- Central processing unit: Board Arduino Mega 2560 controls total activities of circuit such as follows receiving data to decode temperature and humidity
7 signals Bringing displays to LCD and then giving signals for controlling open/close (timer for open /close) electrical equipment
The receiver unit consists of sensors designed to gather signals from the external environment for processing by the Arduino Mega 2560 board This includes the LM35 temperature sensor and the FC-28 humidity sensor Additionally, a 4x4 matrix keypad is included for manual parameter input and control.
- Display unit: is LCD with 04 lines 20 characters to display temperature and humidity of environment, time
- Real-time unit: Using Module 1307 to set up and adjust time of starting to sprinkle and sprinkle time
- Open/close electrical equipment unit: using Relay 5 VDC to close / interrupt active circuits of electrical equipment this unit receives signals from Board Arduino Mega 2560
There out we have source unit provides supply current for total accessories in circuits It creates stable voltage that compliant with index about voltage and current
The Arduino Mega 2560 board features the ATmega2560 microcontroller and is equipped with 54 digital I/O ports, including 15 PWM ports, 16 analog input ports, and 4 UARTs for communication It operates with a 16 MHz Quartz Crystal Oscillator and includes essential components such as a USB connection, an electric jack, an ICSP header, and a reset button This comprehensive setup allows users to easily connect the board to a computer via USB or power it with an AC-to-DC adapter or battery, making it ideal for various microcontroller projects.
2 1 2 Diagram of Board Arduino Mega 2560 ports
Figure 2-2: Pin diagram of Board Arduino Mega 2560
2 1 3 Technical specifications of Board Arduino Mega 2560
- Current for each I/O port: 20mA
- Quantity of Digital port: 54 (15 PWM ports)
- Universal asynchronous receiver/transmitter UART: 4 UART sets
- Serial Peripheral Interface SPI:1 set (port 50-53) using SPI Arduino library
- Inter Integrated Circuit Communications I2C: 1 set
- Flash memory: 256 KB, 8KB used for Bootloader
The LM35 temperature sensor is an efficient device for real-time temperature measurement, offering high accuracy with minimal errors Its compact size and affordability make it an ideal choice for various applications.
- Output voltage resolution 10mV/oC
- Output low impedance: 0.1 for 1mA of load
- Accuracy in reality: 1/4°C with Room Temperature and Outdoor Temperature 3/4°C around -55°C~150°C
Sensor to measure soil humidity, normally output will display at low-level When soil does not have enough water, output will display at high-level Module is
The auto water pouring system features an adjustable soil humidity sensor that allows users to modify its sensitivity using a blue rheostat on the circuit board When the sensor is inserted into the soil, it measures humidity levels, and once the soil reaches a predetermined threshold, the output digital signal changes from low to high, indicating the need for watering.
Figure 2-4: Humidity measure sensor FC-28
- Have permanent hole to assemble conveniently
GND: GND of outside source
DO: Output of digital signal (high level or low level)
AO: Output of Analog signal
Matrix keypad is a soft plastic keyboard including 16 buttons This keyboard linked to Board Arduino and programed for displaying on LCD
Figure 2-5: Matrix keypad 4x4 Technical specifications:
- Voltage and operating current: 15VDC and 100mA
The LCD2004 blue text screen utilizes the HD44780 driver, offering a reliable display with 4 lines and 20 characters per line Its widespread use and abundance of sample code make it an ideal choice for beginners and those working on various projects.
Figure 2-6: LCD 2004 Blue Technical specifications:
- Distance between 02 ports need to be connected: 0.1 inch, easy to connect to Breadboard
- Name of ports written in backside of LCD screen to support connection, arranging electric wire
- Have led light at background Be able to use rheostat or PWM for adjusting brightness to reduce power consumption
- Be able to control with 06 signal wires
- Characters sets is support in English and Japanese
Figure 2-7: Pin diagram of LCD 2004 blue
- VEE port selects contrast This port selected via 01 rheostat 5K a connection head VCC, a Neutral wire
- Port VDD connects to Positive source
- Port selects registers RS (Register Select): have 02 registers in LCD
If RS=0 in writing command mode such as follows deleting screen, open close pointer
If RS in writing data mode such as follows displaying characters, numbers on screen
- Reading/ writing ports (R/W): input reading/ writing allow user to fill information on LCD khi R/W = 0 or reading information of LCD when R/W=1
Enabling port E is essential for the LCD to successfully complete its data transmission This port requires a frequency that transitions from high to low levels, with a minimum width of 450 nanoseconds to ensure proper data handling by the LCD.
- Port D0 – D7: This is 08 ports of 08-bit data, used for sending to information LCD or reading content of registers in LCD
To interface LCD types like HD44780 (e.g., LCD 1602, LCD 2004) with a microcontroller (MCU), a minimum of six ports must be connected to the LCD's RS, EN, D7, D6, D5, and D4 pins In contrast, using an I2C communication module simplifies the connection to just two ports (SDA and SCL) from the MCU to the module, enabling information display on the LCD Additionally, contrast can be adjusted by incorporating a rheostat into the module.
Description of ports (according to order):
The DS1307 Real-Time Clock (RTC) module is designed to store date and time information, including day, month, year, hour, minute, and second, functioning like a digital watch It communicates data using the I2C (Inter-Integrated Circuit) protocol and is equipped with a battery that allows it to maintain information for up to 10 years without needing an external 5V power source Additionally, this module is paired with an AT24C32 EEPROM, which can store up to 32Kbit of data.
Figure 2-10: Pin diagram of Module RTC 1307
Description of ports such as follows:
- X1 and X2 are oscillate input for DS1307 Need oscillate of quartz crystal 32.76 KHz
- Vbat is power supply for chip This source from 2V-3,5V This source helps chip perform continuously when does not have source Vcc and DS 1307 still performs according to time
VCC serves as the communication source for I2C, providing a standard voltage of 5V for use with microprocessors In the absence of VCC, the DS1307 can still function normally with Vbat, although it will be unable to read or write data.
- GND is general ground for Vcc and Vbat
The SQW/OUT port generates a square wave output oscillation frequency However, it does not influence real-time operations, which is why it is typically disregarded in real-time applications.
- SCL and SDA are 02 data bus of DS 1307
Equipment controlling unit uses Relay to close / interrupt electrical circuit this capacity received controlling command from Board Arduino Mega 2560
(Using low voltage open/close high voltage)
DESIGNING PLANT WATERING SYSTEM
3 1 Set up the problem for the system
The automatic plant watering system has been widely applied
Automating the plant watering system enhances cultivation efficiency by reducing labor hours, conserving water, and boosting plant productivity To achieve optimal results, it is essential to carefully consider the specific properties of the plants and the local environmental conditions.
An automatic plant watering system contains:
- Water supply for the system
- System of main and secondary pipes
- Sprinkler heads (may be not applicable depending on watering methods)
- Control box which automatically shut the water pump and electromagnetic valves when necessary
Proposing the solution for the automatic watering system
Options to decide whether to open/shut the watering system as follows:
- Humidity > 90%, the system are not operated
- Humidity of 85-90%, watering in 10 minutes
- Humidity of 80-84%, watering in 15 minutes
- Humidity of 75-79%, watering in 20 minutes
These options are subject to change depending on the region, plants, seasons and weather
Designing the automatic timer, the system is operated when the set time come, the pump is turned on and turn off depending on the humidity
The watering methods which involved watering pipes have the same calculation principles of drainage and hydraulic pipes These are: Determining the
To effectively manage irrigation, we assess the watering zones, water supply, and demand for various plant types, considering the specific area and terrain This analysis enables us to determine the necessary diameters for main pipes, secondary pipes, branch pipes, and laterals, as well as the velocity and pressure of water flow within the system We also calculate the lengths of the pipes and the required connectors, such as swan-necks, T pipe connectors, valves, and curve connectors Additionally, we identify the number of spray heads, bottom bases, and connector pipes needed Finally, we compile a comprehensive list of materials and calculate the minimum supply costs and installation fees.
3 2 1 Estimating the needs of water and the ability for water supply
Depending on each plant, we determine number of watering time, water needed per time The number of watering time depends on the properties of plants and dampness of soil
To determine the necessary amount of water for irrigation, it is essential to estimate the number of watering sessions required In agricultural practice, the frequency of watering should be tailored to the specific soil type and prevailing weather conditions.
Calculating the water requirements for a watering system is crucial for effective design and management Typically, the actual water needed by plants is less than what is supplied, and this demand varies based on the watering method used For perennial plants, water needs generally range from 5-10 liters for drip irrigation, 15-20 liters for jet watering, and 30-40 liters for ditch or sprinkler systems.
For efficient watering, a small area requires only one watering zone, while larger areas should be divided into multiple zones However, if these zones are too large, it can significantly increase the capacity needed for the water pump and the diameter of the main watering pipes, resulting in no economic advantage The optimal approach is to water each zone sequentially.
To effectively divide watering zones, it's essential to create a detailed layout that illustrates the shape and area of each zone This includes measuring the length of the edges, outlining the tree line, and determining the length of each tree row By doing so, we can accurately calculate the number of trees planted in each zone, which is crucial for determining the diameter and length of the main irrigation pipes needed.
To ensure efficient water distribution across the watering zones, it is crucial to accurately calculate the appropriate length and diameter of the main pipes Selecting pipes that are too large can lead to unnecessary expenses, while those that are too small may fail to deliver sufficient water Additionally, using inferior quality pipes can result in breakage and wastage Therefore, careful consideration of pipe size and pressure is essential for optimal performance and cost-effectiveness in irrigation systems.
When planning pipe installation, it's crucial to consider the location carefully and reflect this in the design drawings Typically, in gradual lowland areas, pipes should be aligned with the highest edge of the watering zone This arrangement ensures that water discharged from the main pipes naturally flows from higher elevations to lower ones, optimizing energy efficiency.
For optimal water distribution in areas with flat or slightly elevated terrain, pipes should be strategically aligned along the highest point to effectively supply water to both sides of the region.
3 2 4 Calculating the branch pipes, secondary pipes
A main pipe distributes water through multiple branch pipes, each serving a designated watering zone To ensure efficient water delivery, it is essential to design these branch pipes with equivalent diameters, allowing for a relatively equal allocation of water to each zone.
The secondary pipe is the pipe come through the tree line, bring water to the trees in the line
To determine the parameters for branch pipes, such as length and diameter, the calculation method mirrors that of the main pipe First, measure the length on the drawing with a ruler and multiply it by the drawing's scale ratio The diameter is calculated based on the number of trees irrigated by the pipe, which informs the required water output flow A water flow velocity of 1 meter per second is typically used for these calculations Since branch pipes serve different areas, their sizes will vary accordingly Finally, round up the calculated sizes to select standard pipe sizes available in the market, such as 16, 21, 27, and 32 mm.
For small watering zones with simple shapes and fewer edges, manual drawing and calculations are sufficient However, for larger watering zones, it's essential to use professional graphics software for accurate drawings and to determine pipeline lengths Additionally, Excel can be utilized to calculate the diameters of main, branch, and secondary pipes effectively.
In the drainage industry, energy loss due to factors such as swan-necks, plumbing elbows, valves, and bent pipes is often calculated to understand its impact on water pressure However, for small-sized watering systems, these issues can be simplified or overlooked, as the designs can still function effectively without significant consequences In practice, adjustments can be made, such as increasing watering time, to compensate for any calculation errors.
If the area of watering zone is small, the branch pipe can be unnecessary, the distributing pipes can be attached directly into main pipes
Regarding the flooding watering method, branch pipe 4 is replaced by ditches and drains, level 05 pipes is replaced by secondary ditches
Farmers often face limited funding during the initial stages of their operations, necessitating careful consideration and selection of cost-effective watering methods It is essential to evaluate and calculate the most suitable models to optimize resources Once the harvesting phase is reached, farmers can enhance and upgrade their irrigation systems to improve efficiency.
In cases where funding is limited and the terrain is either flat or gently sloping, the ditch watering model is a cost-effective solution, as it primarily requires investment in a water pump and main pipes, while utilizing small ditches and drains instead of branch and secondary pipes, thereby reducing overall piping costs However, this method is not suitable for uneven or heavily fragmented terrain.
If the ditch watering model is inapplicable, the jet watering model can be
TEST AND RESULTS
In research projects, the results are crucial as they allow us to evaluate the effectiveness of our experiments By analyzing these outcomes, we can identify successful elements and areas needing improvement Furthermore, the experimental results will reveal any shortcomings in the design process and indicate whether the operation has stabilized.
For controlling hardware system, we use LCD 2004 Blue to display the character and use Matrix keypad to edit the setting So that the system have three interface displays:
- Manual mode: By changing the statement of Relay, the user can freely control the watering system
- Time mode: Display will show time and days from Module RTC DS1307 It also show the temperature and water level in tank
- Alarm mode: In this mode, user can watering by setting:
The system operates continuously, providing drip watering regardless of user settings, and remains unaffected by temperature or humidity However, it can adapt to seasonal changes; when the ground dries out, the system automatically activates atomized watering based on the current temperature and humidity levels It monitors environmental conditions hourly, and if the criteria are met, atomized watering will commence for thirty minutes, followed by a thirty-minute break before resuming operation.
CONCLUSION AND DEVELOPMENT ORIENTATION
After months of collaboration with instructors, the team successfully developed an automatic watering system This project emphasized the significance of automated systems, providing a crucial theoretical foundation for their work.
- Learn about automatic watering systems: classification, principles, building method
- Learn about the Board Arduino, methods of using the microcontroller onboard to handle and display the result on the LCD
- Design the hardware and write program for automatic watering systems, ensure the proper operation of controlling circuit
Due to the limited conditions, in this topic, team only design the controlling circuit to turn on/off the electronic devices (water pump) under humidity
If the longer time and higher funding are allowed for the project, the team will have the following development orientations:
- Can program to water more times in a day Program to control more devices
- Design application on smart phone for users to check the status of garden, at the same time, they can install and control via internet
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