My Investigation & Research
When I first began researching ideas for my project, I wanted to focus on creating an artefact that could help address real world environmental issues. Initially, my brainstorming involved thinking of ways technologies like embedded systems could help improve plant growth, research and support environmental sustainability. Environmental issues like deforestation, unpredictable weather patterns and also human error significantly affect plant health and agricultural productivity, impacting ecosystems and communities globally.
These environmental challenges have lead to crop failure and damage to the ecosystem especially in the last forty years, affecting millions of people and animals that live in these ecosystems worldwide. Because of this, I gathered my focus towards systems that could help monitor environmental conditions and respond automatically if a change would occur. I created a list of potential ideas involving sensors that could monitor soil conditions and maintain healthy plant life.
While researching, I discovered that plant dehydration caused by drought, inneficient irrigation systems and human error is a catastrophic issue in agriculture. According to UNICEF, crop failure affects approximately 73 million people globally a year. On the other hand, droughts have also increased by 29% since the year 2000, these environmental issues lead to severe agricultural losses and long term devastation to ecosystems that may be irreversible without change.
As well as wildfires, these environmental issues not only affect people but also wildlife habitats and biodiversity, some estimates suggest that around 137 species of plants and animals every day are lost because of these exact issues.
My research also revealed that irrigation systems can help address these problems significantly. Climate-ADAPT states that irrigated land may produce more than two times the crop yield compared to non irrigated land. By maintaining adequate soil moisture levels, these irrigation systems can support plant health and reduce the risk of soil dehydration while simultaneously supporting wildlife and habitats.
Unfortunately, installing modern irrigation systems are expensive. According to McLeod Landscaping, a modern irrigation system may run costs between $1800 and $5200 depending on system designs and requirements. This cost makes efficient irrigation systems and maintaining sufficient crop yields almost impossible for farmers in economically disadvantaged regions, these areas are also particularly affected by drought, making farming a growing inaccessibility despite the fact that billions of people depend on it.
While researching further, I also discovered that although these irrigation systems contain complex components such as high pressure pipes, filters and pressure regulators, the most essential component is always the water pump, which moves water to plants. Understanding this information helped guide me towards my final idea for my project.
Based on my research, I decided that stripping this idea to its most basic components, designing an automated plant watering system using a micro:bit, water pump and moisture sensor prong would be satisfactory. Demonstrating that although irrigation systems may be compulsory in certain conditions, it does not need to be expensive, reducing drought and maintaining healthy soil.
Plan & Design
The main goal for my project was designing and developing a simple automatic system that could monitor the level of moisture in soil and water plants when needed. The aim was then creating an inexpensive system, to show how embedded technology could be used to monitor environmental conditions. The system was designed to display how automatic irrigation systems help maintain healthy plants and soil and reduce the impact of drought.
Creating the system with the idea in mind that stripping away the most complicated and most costly parts, while maintaining the most basic components such as the water pump was crucial. This project was designed specifically with stakeholders in mind for its low cost and simplicity. Potential users of my artefact range from local farmers who require a cheaper alternative to expensive irrigation and hobby gardeners who are away from home, to farmers in drought stricken areas who see an irrigation system would be a necessity and environmental researches who require monitoring systems to collect data about soil conditions.
Only a few pieces of technologies were selected.
The aim of this project was to design and develop a simple automated system capable of monitoring soil moisture and watering plants when necessary. The main objective was to create a low-cost prototype that demonstrates how embedded technology can be used to monitor environmental conditions and respond automatically. The system was designed to simulate how automated irrigation systems can help maintain healthy soil conditions and reduce the impact of drought in agricultural environments.
At the planning stage, several possible project ideas were considered. One option involved creating a system that monitored plant growth by measuring light levels and temperature. Another idea involved designing a model that simulated tree growth in reforestation projects. However, after researching environmental challenges such as drought and crop failure, it became clear that soil moisture monitoring and irrigation systems were particularly relevant issues. As a result, the decision was made to design an automated watering system that could monitor soil moisture levels and respond by watering plants when the soil becomes too dry.
The project was designed with several stakeholders and end users in mind. Potential users of such a system could include farmers, gardeners, and environmental researchers. Farmers in drought-prone areas could benefit from automated irrigation systems that ensure crops receive adequate water. Gardeners and plant owners could also use similar systems to maintain healthy plants without needing to water them manually. Environmental researchers could use soil moisture monitoring systems to collect data about plant health and soil conditions.
Several technologies were selected to build the system. The main controller used in the project is the BBC micro:bit, which is a microcontroller capable of reading sensor inputs and controlling output devices. The micro:bit was chosen because it is simple to program and allows sensors and external components to be connected easily. The program for the system was created using Microsoft MakeCode for micro:bit, which allows the behavior of the system to be programmed using visual code blocks.
The system uses a soil moisture sensor as the primary input device. The sensor measures how wet or dry the soil is and sends this information as an analogue signal to the micro:bit through pin P0. This allows the microcontroller to continuously monitor soil moisture levels. If the sensor detects that the soil moisture level falls below a predefined value, the system activates a water pump, which acts as the main output device. The pump is connected to pin P1 and delivers water to the plant for a short period of time before turning off again.
The overall architecture of the system is relatively simple. The soil moisture sensor collects environmental data and sends this data to the micro:bit. The micro:bit processes the data and determines if the soil is too dry. If the soil moisture level falls below the programmed threshold, the microcontroller activates the water pump to water the plant. This creates a feedback system where the moisture level of the soil determines the behavior of the pump.
This design allows the system to operate automatically once the program is running. By continuously monitoring soil moisture and activating the pump when necessary, the system demonstrates how automated irrigation systems can respond to changing environmental conditions.
Create
The first stage of my development in creating the system involved putting together all the hardware required. The main controller I'm using being the micro:bit, allowing the sensors and output devices to be connected and programmed to respond to environmental inputs. a Kitronik soil moisture sensor is connected to the micro:bit through pin P0. This allows the micro:bit to read the level of moisture in the soil.
A water pump is then used as the primary output device in my system, with the pump being connected through pin P1, when the micro:bit sends a digital signal into the pin, the pump then gets activated and water is delivered into the soil. Essentially, automatically watering the plant when the soil becomes too dry. Besides these components, a small container to store water in was placed with the pump.
Afterwards, the next stage of developing my project involves code, with the entire program being programmed with MakeCode for the micro:bit with code blocks instead of writing out the code in python, it proved a more simple and understandable alternative. The code repeatedly reads moisture levels in the soil from the sensor, meaning the only manual part of the entire project is simply turning the program on.
The program compares the soil moisture value with a certain threshold (700). In the case that the moisture levels in the soil falls below this threshold, the system then automatically activates the pump for five seconds along with a sad face icon on the LED display to indicate a low moisture level. If the moisture level is above a certain threshold (700), the pump stays turned off and the system keeps monitoring soil moisture levels along with displaying a happy face icon.
I then constructed an algorithm to demonstrate how the system works which is shown below, describing how the system operates automatically once the program begins.
Testing was carried out throughout developing my project with tremendous difficulty, with attempts to try take pictures in moments where the soil dropped below a certain threshold value being impossible to guess, I had to rewrite the code to demonstrate a scenario where the moisture level was too low. Another issue was the Kitronic sensor, depending on how far the prongs were pushed into the soil, at times the system struggled to read whether moisture levels were too low or not. Finally, I had to replace the pump with an LED to display that the code
To conclude, the creation process did produce a working prototype to display how embedded systems can be used in order to monitor real life environmental conditions while responding to them automatically with simple, inexpensive components to keep healthy soil and plant life.
Evaluation
The artefact finally produced for my project was an automatic watering system. After numerous trials, the system successfully monitors soil moisture levels using the sensor and automatically pumping water when the soil becomes dry. In my opinion, the project certainly achieved my main goal of displaying my original idea during the planning stage, which was how an embedded system can monitor soil conditions and respond with pumping water, particularly in drought stricken conditions.
One of the largest strengths of my project is the fact that it is simple, compared to a modern irrigation system using complex filters and pipes, my system only uses a small number of components, however it can still demonstrate the main idea of how an irrigation system should respond to environmental conditions.
Although testing proved difficult at times, (Having to blow dry soil on one condition) the system did respond as expected, when the sensor detected dry soil, the micro:bit would activate the pump, pushing water into the plant. When the moisture levels in soil was satisfactory the pump would remain turned off. Displaying that the program worked correctly, the feedback from the LED display on the micro:bit also helped in indicating physically whether the soil was dry or moist.
My project however does have some limitations, the moisture sensor often had issues with readings, despite even being freshly watered or not because of how deep the prongs were pushed in the soil. In future there could definitely be several possible improvements, such as an improved soil sensor would allow the system to make more accurate decisions to help predict droughts and watering only when absolutely necessary. Overall, this project demonstrates in full how simple embedded systems just like my automatic watering device can be used in real life situations, allowing millions of people access to irrigation systems for a fraction of the price.