Birdie! hardware mvp
Birdie! course map
a hacker's workspace
soldering haptic feedback system
custom power supply

Birdie!

TL;DR

Real-time golf swing tracking system with ESP32 and motion sensors
Live web dashboard with charts and remote control capabilities
Helps golfers develop muscle memory and consistent swing mechanics

Inspiration

Golf is a sport that requires precise technique and muscle memory. Traditional golf training relies heavily on visual feedback and instructor guidance, but many golfers struggle to develop consistent swing mechanics.

We were inspired to create a system that provides tactile feedback to help golfers feel their swing strength and develop better muscle memory. The idea was to make golf training more accessible and effective by providing real-time haptic feedback that correlates with swing performance.

What it does

Our system is a real-time golf club motion tracking system with haptic feedback that:

Tracks swing motion using an ESP32-S3 microcontroller with MPU6050/MPU9250 motion sensors
Analyzes swing strength by measuring backswing angle and gyroscope data
Provides haptic feedback through a brushless motor that vibrates proportionally to swing strength
Displays real-time data on a web dashboard with live charts and swing analysis
Enables remote control of haptic feedback intensity through a web interface

The system helps golfers develop muscle memory by providing immediate tactile feedback about their swing strength, making it easier to achieve consistent swing mechanics.

How we built it

Hardware

ESP32-S3 N16R8 development board for sensor data collection and WiFi communication
MPU6050/MPU9250 motion sensor for accelerometer and gyroscope data
Brushless motor with ESC (Electronic Speed Controller) for haptic feedback
Custom mounting system to attach sensors and motor to golf club

Software

Arduino C++ code for ESP32 with real-time sensor data collection and swing analysis
Python Flask server with WebSocket support for real-time data processing
Web dashboard with live data visualization using Chart.js and Socket.IO
Swing analysis algorithms that calculate backswing angle and correlate it with haptic intensity
WebSocket communication between server and ESP32 for haptic control

Key Features

Real-time sensor data collection at 20Hz
Swing strength calculation based on gyroscope integration
Proportional haptic feedback (0–100% intensity)
Live web dashboard with charts and controls
Remote haptic feedback control

Challenges we ran into

Sensor Calibration: Accurate motion data required extensive gyroscope calibration and filtering to remove noise and drift.
Swing Detection: Distinguishing between actual golf swings and casual movement was challenging. Algorithms were needed to detect backswing phases and filter false positives.
Haptic Integration: We initially attempted to drive the motor through a custom H-bridge circuit, but couldn't get it to work reliably.
Real-time Performance: Achieving low latency between swing detection and haptic feedback meant optimizing both ESP32 code and server processing.
Power Management: Making the system battery-powered and lightweight required careful power optimization.
WebSocket Reliability: Ensuring stable communication between the web dashboard and ESP32 via a phone hotspot.

Accomplishments that we're proud of

Successfully integrated real-time motion sensing with haptic feedback in a single system
Developed accurate swing analysis algorithms that can detect and measure golf swing strength
Created a responsive web interface with data visualization
Achieved low-latency feedback (<100 ms)
Built a complete end-to-end system from hardware sensors to web dashboard
Implemented smooth haptic transitions that feel natural and proportional to swing strength

What we learned

Motion sensor integration requires careful calibration and filtering
Haptic feedback design must balance intensity, user comfort, and battery life
Real-time systems demand timing and data flow optimization
WebSocket communication is powerful for real-time control but needs robust error handling
Golf swing analysis is more complex than expected, requiring multiple sensor inputs and sophisticated algorithms
Sports tech UX must be intuitive and non-intrusive

What's next for Birdie!

Short-term improvements

Enhanced swing analysis with machine learning to detect different swing types (driver, iron, putter)
Battery optimization with sleep modes and power management
Mobile app for easier setup and control
Data logging to track improvement over time