Smart Garden Monitoring System
Various sensors, like light, temperature, and moisture detectors, monitor the conditions of your garden. Based on the moisture level, the device can be water your garden.
Engineer
Amy K.
Area of Interest
Electrical Engineering, Computer Programming
School
Cupertino High School
Grade
Rising Junior
Final Milestone
Final Milestone Video
Bill of Materials
https://docs.google.com/spreadsheets/d/1_R-Tf_-WvsT9OaUphAE8XOXDCee20tbX5Hz6Mlx7Jx0/edit#gid=0
Circuit Schematic

Accomplished
In this milestone, I added an additional sensor, connected my sensors to an app, and got my water pump to turn on and off based on the readings from the moisture sensor. I set up a water tank for my water pump using an inverted plastic water bottle with a hole drilled in the lid. The tube that connected to the ‘in’ side of the water pump went into lid and the tube that connected to the ‘out’ side of the pump flowed into the plant’s pot. I decided to add a water level sensor that lets the user know when the water tank is running low on water. The sensor is comprised of long metal strips that run vertically and rely on the conductivity of water to detect the level of the water. I also designed an app using Blynk that would read data from the sensors via wifi and display the readings so users can check on the conditions of their garden from their phone. I also coded my water pump to respond to readings from the moisture sensor. When low water levels are detected, the water pump will turn on for 10 seconds and then check a minute later to see if the soil is still dry. If it is, the pump will turn on for another 10 seconds, and repeat the process until the soil is sufficiently watered.
Problems I Encountered
One issue I ran into whilst completing this milestone was connecting an app to my circuit board. Initially I tried downloading prewritten code for a web app that someone else designed. However I received several errors that I eventually determined to be a result of outdated programs and deleted files. I decided to switch over to using Blynk, which provided an easy way to design an app and connect it to a microcontroller through wifi. However, this path came with its own set of difficulties, the most prominent of which was when I tried to connect my circuit board to the wifi, I received an error that read “packet too big”. In the end, I switched to a different wifi network, and this solved the problem. Another problem I had was with setting up the water tank for my water pump. I had difficulty sealing the connection between the water tank and the water tube, and thus a lot of water leaked out. Even after adding a considerable amount of duct tape and hot glue, the connection still was not water tight. However, with a great deal of back and forth between taping and gluing and testing, I managed to patch all the major leaks.
Overall Project Reflection
Through this project, I learned a lot about engineering, as well as about problem solving in general. This experience gave me the opportunity to become familiar with many basic components and fundamental engineering concepts. I got the chance to work with breadboards, microcontrollers, and a variety of sensors, which are components that can be used to create a multitude of different projects. I also learned how a voltage divider circuit works and how voltage, current, and resistance relate to each other in the equation V=IR. My experience has given me the confidence to continue making modifications to the project on my own, like making it solar powered or adding a light that turns on when low light is detected. Working on this project also taught me how to deal with challenges that come up during the process. I learned how to troubleshoot and take advantage of the resources available. I also began to properly appreciate the learning opportunity that these problems present and to recognize that without these roadblocks along the way, the process would be far less enriching to my personal growth.
Title
First Milestone
First Milestone Video
Circuit Schematic
