SAE BAJA TEAM MEMBERS: CHAD CHANDLER JOE COFER NATHAN ERAMIAN FRANCIS HAURIS JEFF WONG

BACKGROUND Originated in USC in 1976 Competitions include: EVENT POINTS STATIC 300 Design Report 50 Design Evaluation 100 Cost Report 15 Production Cost 85 Presentation DYNAMIC 700 Acceleration 75 Pulling Maneuverability Rock Crawl Endurance 400 TOTAL 1000 Originated in USC in 1976 Run by SAE Competitions include: Dynamic Events Static Events

RESEARCH PHASE STUDY OF PREVIOUS DESIGNS SAE RULES AND REGULATIONS Suspension Frame Drive Train SAE RULES AND REGULATIONS

PREVIOUS FRAME & SUSPENSION PAST DESIGN DISADVANTAGES SIZE WEIGHT MATERIALS CONSTRUCTION

PREVIOUS DRIVE TRAIN CHAIN DOUBLE REDUCTION ADVANTAGES DISADVANTAGES Inexpensive DISADVANTAGES Stretching Failure Exposed to elements ADVANTAGES Consistent Reliable DISADVANTAGES Expensive Bulky/Heavy

DESIGN PHASE CRITERION PRIORITY DESIGN REGIMENTS HANDLING ESSENTIAL Unsprung to sprung optimization Favorable weight distribution Low CG Congruent suspension kinematics AGILITY Great power to weight ratio Efficient gear train Low GVW RELIABILITY HIGH CNC fabricated frame Accurate FEA MANUFACTURABILITY DESIRED Simplistic design Less joints Multipurpose beams

SUSPENSION DESIGN PROCESS Lotus Suspension Analysis Double Wishbone Front Trailing Arm Rear Testing Modes Bump Roll Steer

SUSPENSION DESIGN PARAMETERS Gross Vehicle Weight (GVW) 520 pounds Weight Distribution Bias (F/R) 45/55 Center of Gravity Height Low as possible Lateral Track Width (F/R) 47/46 inches Longitudinal Wheelbase 60 inches Ride Height 10-12 inches Tire Diameter 23 inches Effective Tire Radius 11.38 inches Static Camber Angle ~ 0 to -1 degrees Static Caster Angle ~ 8 degrees Scrub Radius 0.5 to 1 inches Rack and Pinion Width ~ 10 inches Toe Change in Travel Minimal Roll Axis Inclination Neutral to Slight Oversteer

Autodesk Inventor MODEL FRAME DESIGN PROCESS DESIGN PARAMETERS Autodesk Inventor MODEL Lightweight Compliance with SAE Rules Multipurpose Beams Manufacturable Continuous Runs

DRIVE TRAIN DESIGN PROCESS DESIGN PARAMETERS CVT 10 HP Briggs & Stratton Engine CVT Ratios 3.9 to 1 0.9 to 1 35 mph

DRIVE TRAIN DESIGN RESULTS SOLidworks model GRADEABILITY ~ 50° OPTIMAL REDUCTION 8.29 DYNAMICS 15.7 ft/s²

CURRENT PROJECT STATUS RESEARCH PHASE 100% COMPLETE DESIGN PHASE ~85% COMPLETE PREPARING FOR ANALYSIS PHASE PATRAN/NASTRAN FEA

QUESTIONS ME 435 PROJECTS