# Title Team Members TA Documents Sponsor
61 iPhone 13 with USB-C and selective slow-charging
Houji Zhou
Shreyas Kishore
Xinpei Jiang
Zhicong Fan design_document3.pdf
# Problem

iPhones (and some other mobile Apple devices) have had the Lightning connector for almost a decade. While it has been the dream of many to have an iPhone with a USB-C connector, Apple will very likely not release iPhones with USB-C. A USB-C iPhone will increase interoperability and provide a universal charging standard (which is now used by iPads, MacBooks, Android Phones, many PCs and other devices).

Moreover, phone manufacturers have been competing for faster and faster charging speeds. The convenience of fast-charging comes at a significant cost to battery longevity. The faster we charge our phones, the more quickly its lithium cells wear out. To prevent premature battery failure from regular fast-charging, some phone manufacturers have added an option to charge batteries at an intentionally slow rate (when reasonable, such as when charging your phone overnight). iPhones don’t have this feature, but a USB-C iPhone can achieve selective slow-charging.

# Solution Overview

Our solution is to modify an iPhone 13-series smartphone. The modification entails removing the lightning receptacle inside the iPhone, adding electronics inside the iPhone for the proposed slow-charging functionality and the Lightning-to-USB-C conversion, and making mechanical changes to the iPhone chassis to accommodate and anchor a new USB-C receptacle.

# Solution Components

## Lightning to USB-C Conversion Logic
We will extract and use the components from the "C94" circuit on a certified Lightning to USB-C cable.

## USB-C slow-charging triggering and negotiation
* USB-C's orientation detection to enable/disable the slow-charging feature
* USB-C Power Delivery 3.0 controller to negotiate a maximum of 5V input from the charger.

## Custom Flex Cable
We will need to design a flexible PCB that houses all electronics where the iPhone has adequate internal space (potentially below the battery).

# Criterion for Success
* The modified iPhone charges with USB-C Power Delivery compatible chargers.
* The modified iPhone can transfer data over USB 2.0 bus, compatible with Apple's `libimobiledevice`.
* USB-C charging works in either direction/orientation.
* Plugging in the USB-C plug into the modified iPhone's receptacle in one orientation performs full-speed charging, while the other orientation leads to slow-charging.
* The modified iPhone still functions as intended.

Electronic Replacement for COVID-19 Building Monitors @ UIUC

Patrick McBrayer, Zewen Rao, Yijie Zhang

Featured Project

Team Members: Patrick McBrayer, Yijie Zhang, Zewen Rao

Problem Statement:

Students who volunteer to monitor buildings at UIUC are at increased risk of contracting COVID-19 itself, and passing it on to others before they are aware of the infection. Due to this, I propose a project that would create a technological solution to this issue using physical 2-factor authentication through the “airlock” style doorways we have at ECEB and across campus.

Solution Overview:

As we do not have access to the backend of the Safer Illinois application, or the ability to use campus buildings as a workspace for our project, we will be designing a proof of concept 2FA system for UIUC building access. Our solution would be composed of two main subsystems, one that allows initial entry into the “airlock” portion of the building using a scannable QR code, and the other that detects the number of people that entered the space, to determine whether or not the user will be granted access to the interior of the building.

Solution Components:

Subsystem #1: Initial Detection of Building Access

- QR/barcode scanner capable of reading the code presented by the user, that tells the system whether that person has been granted or denied building access. (An example of this type of sensor: (

- QR code generator using C++/Python to support the QR code scanner.

- Microcontroller to receive the information from the QR code reader and decode the information, then decide whether to unlock the door, or keep it shut. (The microcontroller would also need an internal timer, as we plan on encoding a lifespan into the QR code, therefore making them unusable after 4 days).

- LED Light to indicate to the user whether or not access was granted.

- Electronic locking mechanism to open both sets of doors.

Subsystem #2: Airlock Authentication of a Single User

- 2 aligned sensors ( one tx and other is rx) on the bottom of the door that counts the number of people crossing a certain line. (possibly considering two sets of these, so the person could not jump over, or move under the sensors. Most likely having the second set around the middle of the door frame.

- Microcontroller to decode the information provided by the door sensors, and then determine the number of people who have entered the space. Based on this information we can either grant or deny access to the interior building.

- LED Light to indicate to the user if they have been granted access.

- Possibly a speaker at this stage as well, to tell the user the reason they have not been granted access, and letting them know the

incident has been reported if they attempted to let someone into the building.

Criterion of Success:

- Our system generates valid QR codes that can be read by our scanner, and the data encoded such as lifespan of the code and building access is transmitted to the microcontroller.

- Our 2FA detection of multiple entries into the space works across a wide range of users. This includes users bound to wheelchairs, and a wide range of heights and body sizes.