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Performance Margin for Geometric Road Design
Journal Article
06-11-04-0022
ISSN: 1946-3995, e-ISSN: 1946-4002
Sector:
Topic:
Citation:
Kang, Y. and Ferris, J., "Performance Margin for Geometric Road Design," SAE Int. J. Passeng. Cars - Mech. Syst. 11(4):263-272, 2018, https://doi.org/10.4271/06-11-04-0022.
Language:
English
Abstract:
Although several methods exist for measuring the performance capability of a
vehicle, many require detailed knowledge of the forces acting at each tire
contact patch or do not account for both the vehicle dynamics and the road
geometry. A simple vehicle model is proposed to estimate the upper limit of
performance capability for a given operating condition (the Performance
Envelope) based on the Effective Friction and the road geometry (slope and
cross-slope). The Effective Friction accounts for both the vehicle dynamics and
road surface properties and is estimated, through simulation or experimentation,
using two standard vehicle dynamics tests: constant radius cornering and
straight-line braking. The Performance Margin is defined as the additional
performance capability available before the vehicle reaches the Performance
Envelope, both represented in the intuitive units of gravity. The Performance
Margin is applicable to both geometric road design and vehicle control; both of
which are crucial as transportation agencies and vehicle manufacturers prepare
for the introduction of autonomous vehicles.