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Race Car Vehicle Dynamics

Race Car Vehicle DynamicsWhat I liked most is the chapter on dampers (shock absorbers). It gave me the answers to lots of questions that I had before reading this published work, for example how to choose "ride/handling compromise" when adjusting damping ratio? Why stiffer dampers are more comfortable on large-amplitude bumps, while softer dampers provide smoother ride on small-amplitude bumps? "In an automobile, a suspension is used to reduce the discomfort induced by unevenness in the highway. As measure of discomfort is the vertical acceleration that the passenger is subjected while sitting in the vehicle". The book demonstrates the model where the passenger is linked to the road via three springs in a sequence: tire, coil and the seat, and one damper (shock absorber). There is a graph showing passenger vertical acceleration depending on the amplitude (frequency) of road irregularities, for distinct shock absorbers with various damping ratios. For a stiff shock absorber this diagram shows relatively flat curve, where the vertical acceleration is almost independent of frequency of bumps. For the soft shock absorber, there is a very high peak (several times higher comparing to a stiff damper) of vertical acceleration for the low-frequency bumps, and this acceleration curve quickly decays as the frequency increases. There is another graph, "transient load transfer analysis", which shows that with soft dampers, the suspension load in a turn fluctuates. This is another answer to the question why stiffer dampers (to a certain extent) provide better handling.

The order of the chapters is somewhat sporadic. The books is a mixture of sections of engineering information (formulas), historical background, sketches (e.g. torque arm rear axle suspension), recipes (KONI's published instructions for damper adjustment), and sample data (e.g. Goodyear tire data). Nevertheless, the work is so deep that in a couple of years after it's publication, it had been started being used as a university textbook. Based on comments from faculty, SAE have requested the authors to prepare a supplementary book of problems, to help the universities to examine the students.