Active Suspension Systems Anthony Griffin Bradley Rouse Philip

Active Suspension Systems Anthony Griffin Bradley Rouse Philip Woodward MAE 442 Dr. Klang 5/6/2005

Outline n n n Common Types of Suspensions Active Suspensions Benefits Disadvantages Applications Conclusion

Common Suspensions Front Suspension n Solid I-Beam n Twin I-Beam n Mac. Pherson Strut n Short-Long Arm Rear Suspension n Non Independent Rear Leaf Springs n Non Independent Rear Coil Springs n Trailing Arm n Beam

Solid I-Beam n n n n Used on trucks and other large vehicles Economical Simple design Low Maintenance Excellent load capacity Non-independent design Uncomfortable ride quality Poor handling

Twin I-Beam n n Found on many Ford trucks Forged, cast, or stamped axles Excellent load capacity Requires special equipment for alignment adjustments

Mac. Pherson Strut n n n n One of the most popular systems One Control Arm Ideal for front wheel drive Light weight Economical Good ride quality and handling characteristics Used for both front and rear suspensions

Short-Long Arm n n n Independent design Uses an upper and a lower control arm Uses either torsion bars or coil springs Good ride quality and handling characteristics Heavy and complex design requires a lot of space

Rear Leaf Springs n n n Non-independent design Similar to front solid I-beam axle Large load carrying capacity

Rear Coil Springs n n n Non-independent design Uses coils and control arms instead of leaf springs Good load carrying capacity

Trailing Arm n n Independent Design Uses individual lower control arms Uses coil springs and shocks Good ride quality

Rear Beam n n Non-independent design Stamped beam axles Uses coil springs and trailing arms Light and simple design

Active Suspension Systems Bose Suspension Magneto-Rheological Technology

Bose Suspension System n n Electromagnetic motors at each wheel instead of traditional shocks and struts. Sensors at various locations to detect body and suspension movement. Comparison of Factory-Installed and Bose Suspensions: Body Motion on Bump Course

Bose Suspension System n n Uses sensor measurements to instantaneously counteract road forces Produces excellent ride quality and superior control in the same system

Bose Suspension Components n Linear Electromagnetic Motor ¡ n Power Amplifier ¡ n Responds quickly enough to counter the effects of bumps and road irregularities Sends power to the motor during extension and returns power during retraction Control Algorithms ¡ Observe sensor measurements and send commands to the power amplifiers

Bose vs. Stock Suspension

Magneto-Rheological Technology n n n Dampers contain magnetic particles suspended in fluid Magnetic field within the fluid aligns particles Creates resistance to movement and increases damping Variable magnetic field creates more or less resistance as needed System can change up to 1000 times per second

Benefits Bose Suspension n n n Superior comfort Superior control Reduces body roll during turns Reduces need for camber roll during turns Requires only 1/3 of the power needed by the AC Wider damping range than Magneto-Rheological systems Magnetic Ride Control n n n Improved road handling Improved wheel control Smoother ride than conventional shocks and struts Reduces noise and virbations Continuous range of damping

Disadvantages n n n High initial cost High repair costs Complex systems

Applications Bose Suspension n n System will be offered on high end luxury vehicles within the next 5 years. The same technology has been applied in Military applications. Magnetic Ride Control n n Currently offered on Cadillac SRX and Seville STS models. Offered on the Chevrolet Corvette for the 2003 model year. Mercedes S 600 BMW 7 series

Active Military Application

Conclusion n Active control suspensions offer a wider range of comfort and control than most current suspension systems. Offers unmatched vehicle handling performance. May eventually find their way into more common production vehicles.