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2.810 Car Suspensions James Penn 10/25/2010. Video. 2008 2.810 Contest Second Round. Video. 2008 2.810 Contest Final. Video. 2008 Team C vs Speed Bump. Bump. Bump. Bump. No Suspension. Quarter Car Suspension Model. Quarter Car Suspension Model. 2 nd Order Frequency Response.
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Video 2008 2.810 Contest Second Round
Video 2008 2.810 Contest Final
Video 2008 Team C vs Speed Bump
Quarter Car Suspension Design Unsprung mass should be much less than sprung mass. Suspension should be just stiff enough to keep the unsprung response faster than the input.
Adding Damping logarithmic decrement to damp oscillation of sprung mass by order of magnitude in one period
Natural Frequencies Want low Want high
Natural Frequencies Want low Want high
Concluding Thoughts • Minimize unsprung mass • If rear suspension is pivoting, move motor forward. • Avoid placing center of mass far forward. • Avoid making suspensions too stiff. • Thin, long sheets (k~(t/L)3) • kparallelogram=2*E*b*(t/L)3 • ωn,c≈30rad/s, ωn,us≈100rad/s