Project

# Title Team Members TA Documents Sponsor
20 Vinyl Record Auto-Flipper
 Alfredo Velasquez Bustamante
Mohammed Alkawai
Riyaan Jain
 Chi Zhang design_document1.pdf
final_paper1.pdf
photo1.jpeg
photo2.jpeg
presentation1.pdf
proposal1.pdf
video
Team Members:
- Alfredo Velasquez (av28)
- Riyaan Jain (riyaanj2)
- Mohammed Alkawai (alkawai2)

# Problem Statement:
Vinyl records have experienced a resurgence in popularity due to their rich and warm sound quality, and ability to physically own and view your favourite music and artworks. However, the need to manually flip records disrupts the listening experience, making listening to vinyl records more difficult than it needs to be. To address this, we propose developing an automatic record flipper that detects when one side has finished playing and seamlessly flips the record to continue playback without user intervention.

# Solution Overview:
Our design will integrate three primary subsystems to automate the playback of both sides of a 7-inch vinyl record:
Tonearm Mover: Automates the lifting, positioning, and lowering of the tonearm to start playback and to clear the record during flipping.
Record Flipping Mechanism: Automatically flips the record to play the opposite side upon detecting the end of a side.
Turntable Rotator: Controls the rotation of the turntable to ensure proper playback speed and synchronization with the other subsystems.
We will modify an existing compact record player to incorporate these subsystems, drawing inspiration from the flipping mechanisms used in vintage jukeboxes. Our focus will be on adapting these concepts to a smaller, modern context suitable for 7-inch records.

# Solution Components:
## Tonearm Mover:
Function: Automates the movement of the tonearm to initiate playback and to lift it away during the record flipping process.
Components:
- Servo Motor (HS-318): To precisely control the vertical movement (lifting and lowering) of the tonearm.
- Stepper Motor (290-028): To manage the horizontal distance to get to the record
- Ultrasonic Sensor (HC-SR04): To detect the end of the record by sensing a decrease in distance, indicating the tonearm is below it.
- ESP Microcontroller (Part # not found on ECE supply): ESP microcontroller to process sensor inputs and control motor actions.

## Record Flipping Mechanism:
Function: Automatically flips the record to enable playback of the opposite side.
Components:
- Roller Actuator (Part #W171DIP-21): To rotate the record from one side to the other.
- Side clamps (5075A25): To securely hold the record during the flipping process without causing damage.
- Ultrasonic Sensor (HC-SR04): To confirm the presence and correct positioning of the record before and after flipping.
- Control Circuitry (W171DIP-21): To manage the timing and sequence of the flipping operation.

## Turntable Rotator:
Function: Ensures consistent and accurate rotation of the record at standard playback speeds.
Components:
- DC Motor with Speed Controller (Part #ROB-10551): To drive the turntable at precise speeds (45 RPM for 7-inch records).
- Rotary Encoder (Part #377): To monitor and adjust the rotational speed in real-time.
- Power Supply Unit (Part #168605): To provide stable power to the motor and associated electronics.

# Criteria for Success:
- Automatic Detection: The system accurately detects the end of a record side without user intervention.
- Seamless Flipping: The record is flipped automatically and correctly aligned for playback of the opposite side.
- Tonearm Precision: The tonearm is precisely controlled to avoid damaging the record or stylus during lifting, positioning, and lowering.
- Playback Quality: The system maintains or enhances the audio quality of the original record player, ensuring no degradation due to the automation processes.
- User Safety: The automated components operate safely, posing no risk to users during operation.

Schnorr Protocol Key Fob

Michael Gamota, Vasav Nair, Pedro Ocampo

Featured Project

# Schnorr Identification Protocol Key Fob

Team Members:

- Michael Gamota (mgamota2)

- Vasav Nair (vasavbn2)

- Pedro Ocampo (pocamp3)

# Problem

Current car fobs are susceptible to different types of attacks. Rolling jam attacks are one of such attacks where an attacker jams and stores a valid "unlock" signal for later. Cars with passive keys/cards can be stolen using relay attacks. Since a car can be the most expensive item someone owns, it is unreasonable to allow people to steal them so discreetly by hacking the fob/lock combo.

# Solution

By leveraging public key cryptography, specifically the Schnorr identification protocol, it is possible to create a key fob which is not susceptible to either attack (rolling jam and relay) and also gives no information about the private key of the fob if the signal were to be intercepted.

# Solution Components

# Key Fob

## Subsystem 1

Random number generation - We will use a transistor circuit to generate random numbers. This is required by the Schnorr protocol to ensure security.

## Subsystem 2

Microcontroller - The MCU will run all the computation to calculate the messages. We will likely use an ATtiny MCU so we can use the Arduino IDE for programming. However, some group members have experience with the STM32 family so that is another option.

## Subsystem 3

Power - We plan on using either a 5V battery or 3.3V battery with a boost converter to power the fob.

## Subsystem 4

Wireless Communication - We plan on using the 315 MHz frequency band which is currently used by some car fobs. We will need a transmitter and receiver, since the protocol is interactive.

# Lock

## Subsystem 1

Random number generation - We will use a transistor circuit to generate random numbers. This is required by the Schnorr protocol to ensure security.

## Subsystem 2

Microcontroller - This MCU will also run all the computation to calculate the messages. We will likely use an ATtiny MCU so we can use the Arduino IDE for programming. However, some group members have experience with the STM32 family so that is another option. This MCU will need to have PWM output to control the lock.

## Subsystem 3

Linear Actuator - We plan on using a linear actuator as a deadbolt lock for demonstration purposes.

## Subsystem 4

Wireless Communication - We plan on using the 315 MHz frequency band which is currently used by some car fobs. We will need a transmitter and receiver, since the protocol is interactive.

## Subsystem 5

Power - This subsystem will also likely require 5V, but power sourcing is not an issue since this system would be connected to the car battery. During a demo I would be acceptable to have this plugged into a power supply or a barrel jack connector from an AC-DC converter.

# Criterion For Success

Describe high-level goals that your project needs to achieve to be effective. These goals need to be clearly testable and not subjective.

Our first criteria for success is a reasonably sized fob. There is some concern about the power storage and consumption of the fob.

The next criteria for success is communication between the fob and the lock. This will be the first milestone in our design. We will need to have a message sent from one MCU that is properly received by the other, we can determine this in the debug terminal.

Once we are sure that we can communicate between the fob and the lock, we will implement the Schnorr protocol on the two systems, where the fob will act as the prover and the lock as the verifier. If the Schnorr signature implementation is correct, then we will always be able to unlock the lock using the fob whose public key is associated with full privileges.

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