Project

# Title Team Members TA Documents Sponsor
23 Retrofitting an iMac G3 Mouse to be Bluetooth-Enabled for Use in the 21st Century
 Saif Kazmi
Savannah Moon Pagan
Sebastian Carrera
 Jialiang Zhang final_paper1.pdf
other1.pdf
presentation1.pdf
proposal1.pdf
proposal2.pdf
# Retrofitting an iMac G3 Mouse to be Bluetooth-Enabled for Use in the 21st Century

Team Members:
- Savannah Pagan (spagan6)
- Saif Kazmi (skazmi21)
- Sebastian Carrera (carrera9)

# Problem
Describe the problem you want to solve and motivate the need.

Disposal of outdated technology contributes to approximately 50 million tons of e-waste annually, leading to environmental concerns. Our project aims to demonstrate a sustainable approach to repurposing technology from the past, diverting it from landfills and back into the consumers’ hands.

Specifically, by modernizing old devices, like updating the original iMac G3 to modern computing standards, as well as its original peripherals, such as the mouse included with the device, we not only extend the lifespan of these devices but also preserve their original creative style and design intent. This initiative will align vintage technology with modern computing needs, ultimately fostering a more eco-friendly and innovative technological landscape.

# Solution

Our project aims to replace legacy hardware within the 1998 iMac G3 by utilizing the internal components of a newer Mac Mini computer. The new components will be mounted inside the original iMac shell to give new life to this outdated machine. The original CRT screen will be replaced with a newer LCD screen. The original speakers and disc drive of the iMac will be re-utilized as well, and the ports will be upgraded to the relevant modern port types.

We also aim to update the original Apple USB mouse included with the device by using modern optical sensors and bluetooth to replace the legacy hardware. A modern switch of higher quality and durability will replace the original switch used for the mouse button and rather than physical rollers interacting with a rubberized ball on the bottom of the mouse, we will use an optical sensor to detect mouse movement. The user can customize the sensitivity of the mouse, a feature unavailable on the original hardware. The USB connection will be replaced with bluetooth to communicate with a computer. Due to its wireless nature, the mouse will be battery powered. The mouse can detect when it is not being used and automatically shut off as a battery saving measure, similar to modern bluetooth mice.

# Solution Components
2014 Mac Mini - 8GB RAM, 1 TB of storage

The Mac Mini will be utilized to update the iMac G3 to modern computing standards.

Mouse button

An Omron D2LS-21 switch will be used for the mouse button. It will be placed strategically on our PCB to avoid or minimize modification of the original mouse housing.
https://www.mouser.com/ProductDetail/Omron-Electronics/D2LS-2110M?qs=OcgtsXO%252B3gvFuywVVfHEYw%3D%3D

Optical sensor

A PixArt PMW-3389 or PMW-3360 optical sensor will be used to detect mouse movement. These sensors are commonly used in modern mice. They can be purchased separately, or salvaged from an extremely wide variety of mice.
https://www.tindie.com/products/citizenjoe/pmw3389-motion-sensor/

Bluetooth connectivity/Microcontroller

An ESP32 microcontroller will be used to communicate with the computer over Bluetooth. Additionally, it can process sensor inputs and determine whether the mouse is idle.

Battery/Charging

Our goal is to use a rechargeable lithium ion battery. If space permits, we will use a USB-C connector for charging due to its ubiquity. If this proves to be impractical due to space constraints, we will use a barrel jack, though this is a last resort.

# Criterion For Success

The iMac powers on
The iMac LCD display turns on
The iMac can connect to WiFi
The iMac can function as well as a modern laptop, meaning that it can run multiple applications at once, as well as perform actions within these applications
The iMac ports function
The iMac has Bluetooth connectivity functionality
The mouse can connect to a modern computer with bluetooth
The mouse can provide clicking functions to a modern computer
The mouse can accurately move a cursor on a modern computer
Disregarding the missing USB cable, the mouse must be visually unchanged from the original product
The mouse must last for ??? hours of use (to be determined depending on type of batteries chosen to work with, at least a few hours of charge)

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.