Transcript
•Lightweight, durable, and recyclable Thermoplastic Polyolefin (TPO) body panels, aluminum belly pan and firewall •CNC machined molds made from medium density fiberboard (MDF) to save fabrication time, while facilitating inclusion of complex surface design •Inexpensive vacuum forming process was employed to fabricate the body panels •Water based paints to ensure environmental sustainability
Unique Rear Suspension & Drive Train
Chassis • Thinner walled tubes to facilitate weight reduction without compromising durability • Full AISI 4130 normalized steel • Increased space for easier access to the fuel tank • Maintain structural stiffness of the rear to support the roll cage (FAB bracing) • Torsional rigidity of 883 lb*ft/deg
Team Members
• Highly progressive shock angle • Fully adjustable rebound and compression damping • Fully independent suspension without compromising efficiency • Eccentric cam on one side only to adjust chain tension • Use of constant velocity joints • Hollow mid-axle for weight saving • Designed to eliminate bending loads in the axle • Sprocket driven • Gun-drilled and heat treated AISI 4340 steel stub axles • Constant velocity joints allow efficient power transfer and enable independent suspension travel • Tubular light weight mid-axle
Al Makke JuanPalacio Mike Doody Guo Yu Lane Landry Maoxin Gong
Advisors
Front Suspension
Dr. Bruce Minaker Mr. Bruce Durfy
• Independent double wishbone suspension • Adjustable static caster, camber, and toe angles • Compression, rebound, and preload adjustability, and interchangeable springs • Optimized control arm design for functionality and cost reduction
Body • Lightweight, durable, and recyclable Thermoplastic Polyolefin (TPO) body panels, aluminum belly pan and firewall • CNC machined molds made from medium density fiberboard (MDF) to save fabrication time, while facilitating inclusion of complex surface design • Inexpensive vacuum forming process was employed to fabricate the body panels
Control Arm Analysis • Shock placement close to ball joint housing for reduced bending load • 12o pro-dive improves jump survivability • Geometry designed for minimal bump steer and lateral scrub
Steering Seat Design • Hammock style seat design • Integrated head rest • Obus Forme for driver comfort • Multi-hole tabs for adjustable height and position • Load-rated locking carabineers
Transmission • Accessible engine mount and chain • Adjustable shifter design • 6-speed manual transmission
Brakes • Easily accessible pedals, light weight pedals • Dead pedal for driver comfort • Improve serviceability and manufacturability • 3:0:1 for better ergonomics
• Fast ratio rack and pinion: 180 degrees lock-to-lock • Ackerman deviation of approximately 2.5 degrees • Steering column mounted at 25 degrees
Rear Suspension – Crash Analysis
Fully Independent Rear Suspension
Applied Load Acceleration: Rear Impact
Deformation - Rear Impact Loading – 30kN
Fully Independent Suspension Configuration
Comparison Between Empirical Data and Simulation
Acceleration: Side Impact
Deformation - Side Impact Loading – 30kN
Chassis
Rollover Effect on RHO Members
Von Mises Stress due to Rear Suspension Loading (Torsion)
• 2 forces applied perpendicularly to the high bends of the RHO members of a value of 2 g’s • Maximum Von-Mises stress: 100 Mpa (Safety factor of 4.3
• 2250 lbs applied oppositely in the z direction at the rear suspension mounts • Torsional rigidity of 883 lbs*ft/deg
Modal Analysis: Natural Frequency • Von-Mises stresses at natural frequency of 55 Hz
Front Suspension & Steering
Toe angle change vs. wheel travel •Bump steer minimized for improved handing in rough terrain
Ackerman deviation of approximately 2.5º •Low Ackerman deviation for improved handling in low speed conditions
Vertical roll center location with respect to roll angle Suspension & Steering Assembly
Brakes
Transmission
Stress Analysis on Brake pedal
Brake Pedal Assembly
Light weight Coupler shaft
6 Speed Manual Transmission with Coupler Shaft
Brake Pedal Design
Powertrain
Seat
Vehicle Shifting Sequence
Time History of Vehicle Acceleration
Traction, Resistance, Tire limit, and Available Force as a Function of Longitudinal Vehicle Speed “Hammock” Style Seat Design Time History of Vehicle Speed
