ES-1400

Lab code for ES 1401-11: Intro to Engineering Module (Vanderbilt, MASI Lab). This repo holds the four hands-on lab projects for the course; everything else on the course schedule (agents, pulse coding, radio, keys/secrets, theremin, etc.) is lecture-only and has no code here.

Each lab runs on a Raspberry Pi unless noted otherwise, and uses RPi.GPIO for hardware control.

Labs

Lab-1 — Reinforcement Learning Tic-Tac-Toe

A progression of Tic-Tac-Toe implementations, each building on the last:

File	Description
TTT.py	Basic two-player Tic-Tac-Toe (Tkinter GUI)
TTT_RG.py	Single player vs. a random-move computer opponent
TTT_Min-Max.py	Single player vs. a minimax (optimal) computer opponent
TTT_RL.py	Single player vs. a computer opponent trained with Q-learning (self-play); the trained Q-table is cached to q_table.pkl

Run: python3 TTT_RL.py (or any of the other variants). Requires Tkinter (usually bundled with Python). No GPIO/hardware needed — this one runs fine on a laptop.

Lab-2 — Candy Safe (magnetic card swipe + servo lock)

Simulates a card-locked candy safe: swipe a magnetic card to identify yourself, set a password, then swipe and enter the password again to unlock a servo-controlled latch.

File	Description
Swipe_Read.py	Standalone helper to test reading raw magnetic card swipe data and extracting a student ID
Lab2.py	Full lab: swipe → extract ID → set password → re-swipe + re-enter password to verify → drive servo to the unlocked position

Run: python3 Lab2.py on a Raspberry Pi with a USB magnetic card reader attached and a servo on GPIO pin 17 (BCM numbering).

Lab-3 — Ultrasonic Sensing (theremin-style buzzer)

Reads distance from an HC-SR04 ultrasonic sensor and maps it to a buzzer tone in real time — closer objects produce a higher pitch (2–400 cm mapped to 200–2000 Hz).

Run: python3 Lab3.py on a Raspberry Pi with the ultrasonic sensor's trigger/echo pins on physical pins 7/11 (BOARD numbering) and a buzzer on pin 18. Ctrl-C to stop.

Lab-4 — Networked Sensing

Extends Lab-3 across two Raspberry Pis: one measures distance and streams it over a TCP socket, the other receives the readings and plays the corresponding tone on its own buzzer.

File	Description
Lab4sender.py	Runs on the "sensor" Pi — measures distance via the ultrasonic sensor and sends each reading to the receiver over a socket
Lab4receiver.py	Runs on the "buzzer" Pi — receives distance readings and converts them to a buzzer frequency
send.py / receive.py	Minimal standalone TCP messaging scripts, useful for testing connectivity between two Pis before running the full lab

Run: on the receiver Pi, python3 Lab4receiver.py and enter a port to listen on; on the sender Pi, python3 Lab4sender.py and enter the receiver's IP address and the same port. Both Pis need to be on the same network.

Requirements

• Python 3
• RPi.GPIO (Labs 2–4; Raspberry Pi only)
• Tkinter (Lab 1)
• Standard library only otherwise (socket, termios, tty, getpass, pickle, random)

Repo layout

Lab-1/   Reinforcement learning Tic-Tac-Toe
Lab-2/   Candy Safe (card swipe + servo)
Lab-3/   Ultrasonic sensing (single Pi)
Lab-4/   Ultrasonic sensing over a network (two Pis)