Automated Football Launcher: Methods for Completing Autonomous Football Passes using Motion Tracking Carmine Milone, Joe Milone, Alex Heydari, George Yue, and Joe Fyneface Georgia Institute of Technology School of Electrical and Computer Engineering March 17, 2010

Project Overview Continuously track a moving object using web- cams to deliver a football accurately Apply technology for football teams in order to reduce work load for trainers Estimated development costs at $80,000; initial cost of a prototype system will be approximately $1,500

Automated Football Launcher Components Logitech Orbit Web-cam Phidgets Motor Control Board Two 12V DC Motors Pan/Tilting Platform Phidgets Relay Board Compressed Air Launcher

Design Objectives Continuously track a moving object using web- cams in real-time Analyze the path of the object to determine the launching angle and direction Utilize a motor control algorithm to attain a specified trajectory Launch a football triggered by a relay board

Summarized Design Flow chart Identify objectFind position Calculate route/trajectory Rotate/Tilt launching platform Launch the football

Current Status Web-cam tracking program completed Motor control and relay board code written and tested Compressed air launcher and platform are under construction

Logitech Orbit Web-cam Resolution: up to 1600 by 1200 pixels – Currently using 640x480 resolution for better performance Color depth: 24-bit true color Frame rate: 30 FPS – 15 to 20 FPS when detection algorithm is running Interface: USB 2.0

Phidgets HC Motor Control Board Controls up to two DC motors Updates data 50 times/second Can provide up to 18A Utilizes USB connection

Motor Specifications Type: DC Gear motor Voltage: 12V Current: 14A-19A – Currently programmed to utilize 7A Controlled using Phidgets HC Motor control board

Pan/Tilting Platform

Phidgets Relay and I/O Board Relay board: – 2 relays for switching AC/DC – Up to 240VAC at 10A – Up to 100VDC at 5A – Will open/close air valve I/O board – 8 analog inputs – 8 digital inputs / outputs

Compressed Air Launcher 6 in. diameter PVC pipe – Can be interchanged with a 3 in. diameter PVC pipe 135 psi 3 gallon air tank Controlled with Sprinkler valve

Technical Approach Calculate the offset between the center of the web-cam's frame and the object’s position Translate the offset into a motor control launch angle and direction Predict the object’s final position and launch the football timely to the specified location

Web-cam Tracking Algorithm

Tracking using Blob Detection Web-cam searches for a specific color Code written in C# using.NET framework Utilizes DirectShow library Accesses pixel data directly from memory

Web-cam Tracking Demo

Motor Control Coded in C# Tracking determines degrees of rotation/tilt Use small movements as a unit of translation Keep velocity constant

Trajectory Algorithm Use kinematics to determine angles of the platform θ H

Alternatives Linx RF modules were developed and tested for tracking – RSSI / Triangulation tracking methods were designed Did not work as intended due to destructive interference Lower frequency RF modules are being considered

Challenges / Problems Building the compressed air launcher and platform Implement a web-cam algorithm to detect objects over 30 yards away from the launcher – Lighting constraints Lack of commercial football launcher Develop RF modules for tracking

Marketing Estimated System cost – Logitech Web-cam: $100 – DC Motors and control board: $200 – Moderately powered computer: $500 – Air compressor launching system/platform: $700 Total: approximately $1500

Schedule 03/29/2010: Finish building platform 04/07/2010: Complete compressed air launcher 04/16/2010: Integrate all components 04/30/2010: Complete system testing 05/06/2010: Final Demonstration

Future Work Consider more complicated tracking methods such as RF frequency modulation Integrate with the Jugs Football Thrower Create a hopper system to automatically feed and reload multiple footballs

Project Summary Two candidate methods to track an object have been compared and evaluated Optical tracking has shown promising results while RF needs more development Optical tracking performs reasonably well if the object is within 30 yards

Any questions, suggestions, or comments?