CS334 Final Project - Interactive Rotating Table

A rotating table system with encoder-based positioning, controlled by Arduino and interfaced through Python. Features multiple interaction modes including object recognition with Reachy robot emotions, and a Ouija board spirit communication interface.

Hardware

• Arduino UNO with BTS7960 motor driver
• Rotary encoder (1425.1 PPR) on pins 2/3
• Belt-driven table with 11.625:1 ratio (16,567 ticks per revolution)
• Reachy Mini robot (optional) for emotional expressions
• Microphone for voice input

Wiring

Component	Arduino Pin
RPWM	5
LPWM	6
REN	7
LEN	8
Encoder A	2 (interrupt)
Encoder B	3 (interrupt)

Installation

pip install pyserial SpeechRecognition pyaudio openai requests
pip install opencv-python pillow transformers  # for cs334_v5.py

Set your OpenAI API key:

export OPENAI_API_KEY=sk-your-key-here

Upload pulley.ino to the Arduino.

Scripts

ouija.py - Ouija Board Spirit Communication

A mystical Ouija board that spells out responses letter-by-letter. Uses GPT-4o-mini as an "ancient spirit" that gives cryptic one-word answers.

Layout (29 segments):

• Segment 0: YES
• Segment 1: GOODBYE
• Segment 2: NO
• Segments 3-28: A through Z

# Run full Ouija session (voice or text input)
python ouija.py

# Print segment map
python ouija.py --map

# Test spelling a word
python ouija.py --test HELLO

# Test moving to a specific segment
python ouija.py --segment 14

table_control.py - Manual Table Control

Interactive command-line control for the rotating table. 30 segments at 12 degrees each.

python table_control.py

Commands:

• <number> - Go to segment 0-29
• d <degrees> - Go to exact degrees
• z - Zero encoder at current position
• p - Print current position
• s - Stop motor
• q - Quit

cs334_v5.py - Reachy Object Recognition

Full interactive system with camera, BLIP captioning, and Reachy robot emotions. Press keys in the OpenCV window:

• SPACE - Capture frame and react based on emotion rules
• a - Ask Reachy a yes/no question (voice input)
• y/n - Manually trigger happy/sad emotion
• 1/2/3 - Motor left/right/stop
• 4-7 - Go to zones 0-3 (90-degree increments)
• p - Print encoder position
• z - Zero encoder
• q - Quit

fetch_item.py - Item Retrieval

Rotate to a specified degree, let Reachy observe, then return to home position.

Arduino Commands (pulley.ino)

Serial commands at 115200 baud:

Command	Action
1	Spin left
2	Spin right
3	Soft stop
p	Report encoder position
z	Zero encoder (set home)
g<ticks>	Go to absolute position (e.g., g1425)

Architecture

[Microphone] -> [Speech Recognition] -> [Python Script]
                                              |
                                              v
                                        [OpenAI GPT]
                                              |
                                              v
[Arduino] <-- Serial (115200) <-- [Motor Commands]
    |
    v
[BTS7960 Driver] -> [Motor] -> [Belt] -> [Table]
    ^
    |
[Encoder] -- position feedback

Encoder Math

• Encoder PPR: 1425.1
• Belt ratio: 11.625:1
• Ticks per revolution: 16,567
• Position accuracy: ~0.022 degrees