Implications of As-built Highway Horizontal Curves on Vehicle
Dynamic/Kinematic Characteristics Under Adaptive Cruise Control
Abstract
Due to the presence of the roadâ\euro™s curvature and sensorsâ\euro™
limited field of view, as-built highway curves designed based on
traditional human-driven vehiclesâ\euro™ characteristics pose a
challenge to the adaptive cruise control (ACC) system and its shared
control. However, very few efforts in the literature were expended on
exploring the adaptability of the ACC system-dedicated vehicle (V-ACC)
from the perspective of vehicle-road geometry interaction. Therefore,
the objectives of this study are threefold: (i) to investigate the
implications of existing horizontal curves on V-ACC dynamic and
kinematic characteristics; (ii) to unravel the impact mechanism of curve
geometric features; and (iii) to evaluate the ACC systemâ\euro™s
adaptability from different aspects and extract the critical curve
geometric features. To this end, a virtual co-simulation platform was
established and validated by the OpenACC database. A series of tests
featuring circular curve radius
(RC), desired speed
(Vde), and desired clearance
were created, and V-ACC characteristics were output. The results show
that: (i) a smaller RC causes
V-ACC characteristics toward the margins of safety, comfort, and speed
consistency, but neither sideslip nor rollover occurs, and speed
consistency is good; (ii) the driver and passengers (if any) feel
comfortable at Vde = 40, 80-100
km/h following the leading car, but they may feel â\euro˜moderately
uncomfortableâ\euro™ at Vde =
50-70 km/h when RC decreases
toward its lower limit; and (iii) asymmetrical maneuvers and discomfort
would exist before and after the circular curve. These findings could
help road administrators regulate V-ACCâ\euro™s behaviors and improve
its road-oriented operation design domain.