CAPSTONE DESIGN EXPERIENCE 2016 Quarter Scale Tractor Austin Bossaer, Derek Franke, James Marschand, and Zach Hurd (All are graduating with degrees in Agricultural Engineering-Machine Systems) Background Customer Requirements Drivetrain The ASABE hosts the International ¼ Scale Tractor Student Design Competitive tractor pullers Objective: Increase reliability & Reduce noise. Competition each year where 27 universities build a tractor and compete in a • Durable drivetrain • Simplified drivetrain: unique 360-degree workplace experience. Teams are only given an engine • Serviceable design - Cub Cadet3 speed w/ reverse transaxle and rear tires and the rest must be designed following strict rules similar to • Safe and easy to control -Final drives and lock out hubs design standards. The Purdue Quarter Scale (PQS) team strives to deliver a • Maximize gear ratio - Continuously variable transmission (CVT) tractor that focuses on manufacturability, serviceability, maneuverability, - 4WD Kubota front axle safety and ergonomics. • Engine orientation rotated 180° Project Goals - Eliminates need for transfer case The team’s goals for this tractor design are: • 5% weight reduction • Drivetrain capable of 2700 lb. chain load Alternative designs: 2WD, actuating CVT, hydrostatic • Simplified operator station- fewer and less complicated parts transmission, electronic locking differential • Real time speed feedback • Operating noise below 90dB Operator’s Station Design Constraints Objective: Simplify Steering System. • Closed loop hydraulic steering system Each team of engineers were constrained by the rules of the ASABE ¼ Scale - Eliminates hydraulic pump and reservoir Tractor Student Design Competition. The design constraints were: - 7% weight reduction • Weight – Tractor may not exceed 800 lbs. maximum gross vehicle weight • Suspension operator station • Length – No part of the tractor may protrude further forward than 96 • Tilt Helm and adjustable seat inches from the center of the rear axle • Accommodates a 95th percentile operator • Width – No part of the tractor may be wider than 72 inches Alternative designs: electronic steering, electric throttle There are several other limitations and rules that the team must meet to qualify for the competition, regarding component design, safety, noise, etc. Data Acquisition & Electronics Interface Impact and Sustainability Objective: Provide real time performance • New designs reduce number of components and shielding feedback, data logging, and electronic controls. - Simplified drivetrain and operator station Serviceability • Real Time feedback • Fluid drainage tubes to ensure controlled disposal -Engine speed • Light weight, 4x4 drivetrain reduces soil compaction and yard damage. • Simplified shielding -Wheel speed • Accessible without removing -Ground speed tractor shielding • Basic touch screen controls • Maintenance log available • Access to operators manual and maintenance log Economic Analysis Tractor display monitor or • Phone application provides mobile feedback • Cost breakdown uses ASABE competition pricing constants android app • 3.5% reduction in adjusted manufacturing cost from 2016 tractor • Minimal hardware variations Exhaust System • Engine, transmission, and drivetrain account for 53% of costs Manufacturability Objective: Minimize operating noise. • Twin muffler system • Simplified shielding - 27% noise reduction • Common materials and fasteners • Shielding allows maximum heat dissipation and • CNC plasma cutter, press brake, safe operation and powder coating • Multiple exhaust packages in order to meet • Creo modeling and subassembly customer needs technique Alternative designs: delta/vortex flow exhaust, added heat absorption material

Technical Advisors: Instructors: Acknowledgements: Dr. John Lumkes Dr. Bernie Engel Special thanks to Scott Brand, the ABE Daniel Skelton Dr. Bob Stwalley department, and this year’s Quarter Scale sponsors for their continued support of our team!