Project

# Title Team Members TA Documents Sponsor
74 Affordable Soil Moisture Monitoring for Home Gardeners
 Arnav Garg
Michael Yan
 Sanjana Pingali proposal1.pdf
# Team Members:
- Arnav Garg (arnavg8)
- Anurag Ray Chowdhury (anuragr3)
- Michael Yan (myan13)

# Problem:
Maintaining soil moisture is crucial for plant health, especially for home gardeners, farmers, and even plant enthusiasts. Many individuals struggle to monitor soil conditions effectively, leading to over/underwatering, which damages plants.

Traditional methods involve soil moisture testing, requiring frequent checks and guesswork. Advanced irrigation systems exist but are expensive and designed for large scale agriculture, making them inaccessible for gardeners.

To bridge this gap, we need low cost solution that monitors soil moisture and environmental conditions while providing alerts when needed

# Solution:

We propose PlantSense, a low cost ESP32 based PCB that integrates environmental sensors to provide realtime monitoring for gardeners

This system will:
- Continuously measure soil moisture, temperature, and humidity.
- Use an ESP32 for wireless connectivity to send alerts and log data on a web dashboard.
- Provide automated alerts via mobile notifications when soil conditions become unsuitable.

By offering an affordable smart plant care system, PlantSense makes gardening precise for beginner planters


# Solution Components

ESP32 (Main Controller)
• Handles sensor data processing and wireless communication
• Stores soil moisture thresholds and triggers alerts
• Sends data to a mobile/web dashboard for remote monitoring

# Soil & Environmental Sensors

Soil Moisture Sensor (Capacitive Soil Moisture Sensor v1.2)
• Measures water content in the soil
• Helps prevent overwatering and underwatering

Temperature & Humidity Sensor (DHT11/DHT22)
• Monitors air temperature and humidity around plants
• Useful for optimizing growing conditions for different plant species

Light Sensor (BH1750)
• Measures ambient light levels
• Helps ensure plants receive enough sunlight

PCB (Custom Hardware Board)
• Provides plug-and-play connectivity for all sensors
• Includes voltage regulators for stable sensor operation

Connectivity & Data Logging
• Wi-Fi/Bluetooth (ESP32) → Sends real-time data to a mobile app
• Web dashboard/mobile app for historical tracking of soil moisture trends

# Hardware Background

The ESP32 is system core which is responsible for collecting, processing, and transmitting soil data. Furthermore, the ESP32 is:
• Affordable (~$5-$10 per unit)
• Energy-efficient (supports battery or direct power operation)
• Ideal for IoT applications (Wi-Fi + Bluetooth)

The soil moisture, temperature, and humidity sensors are used in agriculture and indoor gardening. By combining them into a single smart monitoring system, we provide an affordable solution for plant owners.

# Future Expansion

PlantSense has the potential to evolve into a fully automated plant care solution. Future upgrades could include:
• AI-based predictive analytics to detect watering patterns.
• Automated irrigation control by connecting to a smart watering system.
• Additional sensors for CO₂, nitrogen, and soil pH monitoring.
• A battery-powered version for outdoor gardens.
• Smart home integration with Alexa, Google Home, and Apple HomeKit.

This system could benefit home gardeners, greenhouse operators, and small-scale farmers looking for an affordable, data-driven way to care for plants.

# Criterion for Success

Affordability
• The system should cost under $50-$80, making it cheaper than commercial smart gardening systems

Ease of Use
• The PCB should be plug-and-play with clear documentation
• Should be easy to install in potted plants and gardens

Functionality
• Must successfully monitor soil moisture, temperature, and humidity with real-time updates.
• Provide instant alerts via mobile notifications.

Scalability and Expandability
• The design should support future integration with more sensors.
• Must support remote data logging for historical analysis.

Performance
• The system should provide real-time updates every 10-15 seconds to our web system

# Conclusion

PlantSense is an affordable, plug and play monitoring solution that makes plant care easier and precise. By bridging the gap between manual testing and expensive smart irrigation systems, it ensures optimal growing conditions for both beginner and experienced gardeners.

Active Cell Balancing for Solar Vehicle Battery Pack

Tara D'Souza, John Han, Rohan Kamatar

Featured Project

# Problem

Illini Solar Car (ISC) utilizes lithium ion battery packs with 28 series modules of 15 parallel cells each. In order to ensure safe operation, each battery cell must remain in its safe voltage operating range (2.5 - 4.2 V). Currently, all modules charge and discharge simultaneously. If any single module reaches 4.2V while charging, or 2.5V while discharging, the car must stop charging or discharging, respectively. During normal use, it is natural for the modules to become unbalanced. As the pack grows more unbalanced, the capacity of the entire battery pack decreases as it can only charge and discharge to the range of the lowest capacity module. An actively balanced battery box would ensure that we utilize all possible charge during the race, up to 5% more charge based on previous calculations.

# Solution Overview

We will implement active balancing which will redistribute charge in order to fully utilize the capacity of every module. This system will be verified within a test battery box so that it can be incorporated into future solar vehicles.

Solution Components:

- Test Battery Box (Hardware): The test battery box provides an interface to test new battery management circuitry and active balancing.

- Battery Sensors (Hardware): The current battery sensors for ISC do not include hardware necessary for active balancing. The revised PCB will include the active balancing components proposed below while also including voltage and temperature sensing for each cell.

- Active Balancing Circuit (Hardware): The active balancing circuit includes a switching regulator IC, transformers, and the cell voltage monitors.

- BMS Test firmware (Software): The Battery Management System requires new firmware to control and test active balancing.

# Criterion for Success

- Charge can be redistributed from one module to another during discharge and charge, to be demonstrated by collected data of cell voltages over time.

- BMS can control balancing.

- The battery pack should always be kept within safe operating conditions.

- Test battery box provides a safe and usable platform for future tests.