Project

# Title Team Members TA Documents Sponsor
73 Circle of Life: Automated Desktop Aquaponics System
 Aishwarya Manoj
Anjali Aravindhan
Estela Medrano Gutierrez
 Manvi Jha design_document1.pdf
photo1.jpg
photo2.jpg
proposal1.pdf
# Circle of Life: Automated Desktop Aquaponics System

# Team Members:
- Aishwarya Manoj (am133)
- Anjali Aravindhan (anjalia2)
- Estela Medrano (estelam2)

# Problem

Urban living and limited indoor space make it difficult for individuals to grow fresh produce sustainably. Aquaponic systems offer an efficient solution by combining fish cultivation and plant growth in a closed-loop ecosystem, but existing systems require frequent manual monitoring and maintenance. Current desktop-scale aquaponics kits often lack intelligent control features and are cost-prohibitive for individual users.

# Solution

This project proposes the design and construction of a small desktop smart aquaponics system integrating automated environmental and fluid control. The system consists of a compact fish tank and plant grow bed forming a closed-loop water circulation path. An electronically controlled pump circulates water between the tank and grow bed, while a motorized dispensing mechanism provides automated fish feeding. A programmable grow-light module delivers controlled lighting cycles for plant growth. Embedded sensors monitor key system conditions such as water flow, ph level and water temperature. A microcontroller schedules feeding and lighting and processes sensor data. Depending on budget and difficulty, we may add more or less capabilities.

# Solution Components

## Subsystem 1: Fish Feeder Subsystem

A simple automated fish feeder will be implemented using an SG90 servo motor (linked below) operating between two angular positions, one away from the fish tank and another towards the fish tank for dispensing food. A custom 32-printed food container will be mechanically coupled to the servo shaft using screws and will include a small outlet opening that allows food to dispense when the container is rotated downwards. The servo motor will be controlled via PWM signals generated by a microcontroller. This microcontroller will also serve as the controller for the other subsystems.

[https://www.digikey.com/short/0r42n3vv](url)

## Subsystem 2: Lighting Subsystem

The lighting subsystem serves as the artificial light sources for plants in our desktop aquaponics system. The purpose of this subsystem is to make sure plants will get the correct amount of light and intensity per day to simulate growth due to sunlight from the Sun. The lighting subsystem will use LED colored lights with alternating blue and red colors to simulate sunlight and promote photosynthesis. We plan on using the Royal Blue and Deep Red ASMW-LL00-NKM0E LEDs from DigiKey (also linked below this section) connected to a LED driver to both control the lighting system and step down the input voltage of the PCB to the 3.08V needed by the lights. This LED driver will be in the same PCB as the microcontroller system and will use the same microcontroller. It will be mounted above the plants and the aquarium portion of the aquaponics system and shine down upon the plants.

[https://www.digikey.com/short/zcmqv3wj](url)

## Subsystem 3: Water Quality Subsystem

This subsystem monitors water quality through various sensors and allows for us to ensure that the aquaponic system is working properly. The three main components of this subsystem are the water flow sensor (314150005 from DigiKey), the water PH sensor (SEN0161 from DigiKey), and the water temperature sensor (Waterproof 1-Wire DS18B20 Digital temperature sensor) As we have a water pump pushing water up through our aquaponic system and bringing water to the plants above the fish tank, we need to measure the flow rate of the water to ensure that this component is operating effectively. The water flow sensor will thus measure the flow of water and ensure that the water is pumping effectively up the system. Alongside this, we will have a PH sensor to measure the PH of the water, which is critical for the health of both the fish and the plants. As we aim to have beta fish in the tank, that requires a PH of roughly 6.8 to 7.5, and we will have plants that require that slightly acidic to neutral PH range as well. If the PH is outside of this range, we will have a LED indicator (sourced from our component kit) so that the user knows it is time to change the water. Finally, we will have a sensor measuring the temperature of the water to ensure that it is habitable for the fish. Again, for beta fish this requires a temperature of 76 to 85 degrees Fahrenheit. The temperature sensor will measure the temperature of the water in the tank and if it is too high or too low, an LED indicator will be triggered, allowing the user to change the water or the temperature of their room.

[https://www.digikey.com/short/r7f95h7j](url)

[https://www.adafruit.com/product/381?srsltid=AfmBOop4JLBfv5qedUGq36frDQX9vyVTusMKieUlSaGwtCNAFJlJTlm4](url)

[https://www.digikey.com/short/v9btn5d9](url)

## Subsystem 4: Power Subsystem

The power subsystem’s main goal is to provide power to the other subsystems in this project, including but not limited to the lighting, fish feeder, water quality, and pump. To start the project will need an AC to DC 12V converter that is linked below. The voltages of the components will be the following:
- The microcontroller unit, either a STM32- or a ESP32-class IC, requires 3.3 volts. For example, a STM32G4/F4 or a ESP32-S3.
- The LEDs require a voltage of 3.08V and 200mA.
- The water flow rate sensor requires an input voltage of at least 5V.
- The PH sensor also requires an input voltage of 5V. The water temperature sensor’s power is between 3.0V to 5.5V.
- The circulation pump ranges from 6V to 18V.
- The water feeder servo uses 5V.
Thus, we will be using a voltage regulator to step down the voltage from 12V to 5V for all of the systems, and a LDO to step it down to 3V for the LEDs.

[https://www.digikey.com/short/dbfnfn48](url)

[https://www.digikey.com/short/bf0mqfjh](url)

[https://www.amazon.com/12V-Power-Supply-Adapter-Transformer/dp/B07DMFN2YN](url)

## Subsystem 5: Water Pump Subsystem

The water pump will be in series with the water flow sensor, sending the water from the fish tank up to the plants. We will be using a FIT0563 circulation pump that is waterproof, and depending on the water flow sensor’s outputs, we will be controlling the speed of the circulation pump by PWM modulating the supply voltage using a MOSFET.

[https://www.digikey.com/short/cr79t182](url)

# Criterion For Success

- The pH sensor accurately measures the pH
- The temperature accurately measures the temperature of the water
- The flow rate sensor accurately measures the flow rate
- Water is able to flow in a circular loop from the aquarium to the plants and vice versa
- Automated fish feeder is able to supply food into the fish tank once every 24 hours
- Lighting is able to mounted above the plants and has daily lighting schedule that changes based on the time of day (24 hour schedule implemented)
- The LED indicators accurately indicate temperature that is too cold or warm, and water that has a PH too high or low (unsafe for fish)

Economic Overnight Outlet

Chester Hall, Sabrina Moheydeen, Jarad Prill

Featured Project

**Team**

- Chester Hall (chall28), Sabrina Moheydeen (sabrina7), Jarad Prill (jaradjp2)

**Title**

- Economic Overnight Outlet

**Problem**

- Real-time pricing in ISOs, such as the Midwest, California, New England, and New York, provides differentials in electricity prices throughout the day that can be taken advantage of. The peak price of electricity compared to the minimum prices can feature variations of up to 70%. With price agnostic charging, this results in unnecessary costs for those who charge devices (see attached spreadsheet). This same principle can thus be scaled for large commercialized applications requiring high-capacity batteries, resulting in a higher savings potential to be taken advantage of.

- Calcs: https://docs.google.com/spreadsheets/d/1JBzt2xm0Ue4a_teosdak623h0zSP5nHRKi7Wi8rMcPo/edit?usp=sharing

**Solution Overview**

- We will create a device that can fetch real-time prices from regional ISOs and enable charging when prices are lowest. Our primary application will be centered towards warehouse electric vehicles using high-capacity, fast-charging lithium ion batteries. Such vehicles include forklifts, cleaning machines, and golf carts.

**Solution Components**

- [ISO LMP API] - Through use of a WiFi-enabled microcontroller we can fetch real-time prices and build our control system around these values.

- [Passive High Performance Protection] - In order to provide downstream safety to the loads, we will ensure the device features surge protection and is rated for the high current of fast charging. The switching of the connection will be done with a contactor whose coil is energized according to the microcontroller.

- [Device Display] - LCD display to show information about the current energy price and the current day’s savings.

- [Manual User Override] - The device will feature a manual toggle switch to either enable or disable the cost-optimized charging feature allowing users to charge loads at any time, not necessarily the cheapest.

- [User Interface] - Software application to allow for user input regarding the time of day the device must be charged by. The application will also display information about total savings per week, month, or year and savings over the device’s lifetime.

- [Control Power Converter] - In order to run the low voltage control systems from the outlet, either 120VAC or 3-phase 480VAC, we will need to step this down to a low DC voltage of around 3.3VDC.

- [Memory System] - Microcontroller capable of performing control function within user specified parameters.

- [Device Connection] - Connectivity to the battery of the device being charged so that current state of charge (SoC) information can be used. Potential experimental filter algorithms will be used in order to estimate the SoC automatically, without requiring the user to input the specific data of the device being used.

**Criterion for Success**

- Able to charge devices at lowest cost times of the day and display current pricing and savings information. The upfront cost of a large-scale reproducible product must be less than the lifetime savings incurred by purchasing the product. Users without an engineering background can easily analyze their savings to visually recognize the device’s benefit.