An Experimental Study on Lateral Acceleration of Cars in Different Environments in Sichuan, Southwest China

Abstract

In view of the tremendous improvements in the dynamic performance of automobiles and changes in the composition of drivers over the past several decades, it is valuable to examine the distribution of automobile’s lateral acceleration in new environments. The lateral accelerations, speeds, and trajectory curvatures of a passenger car on twelve highways with different design speeds and topographies were obtained. By synchronizing, matching, and counting, the distribution of the lateral acceleration was obtained, and the level of driving comfort was estimated. The10th,15th,50th,85th, and90thpercentile values of the lateral acceleration on three road types (six-lane road, four-lane road, and two-lane road) were found. Combined with scatter diagrams of the lateral acceleration over the curvature, the negative correlation between the lateral acceleration and the curvature was analyzed and interpreted. In addition, regression models of the lateral acceleration with the curvature for the three kinds of roads were established. Based on scatter diagrams of the lateral acceleration over the speed, regression models of the averageaydepending on the speed and the85thpercentileaydepending on the speed of passenger cars and buses were established. The research provides calculation parameters and a control basis for operating speed prediction, pavement material design, and maximum and minimum limit value determination for the superelevation ratios and curve radii.

Integration of auto‐steering with adaptive cruise control for improved cornering behaviour

“…Py,ssΓywy(t))dτ (27) and thus, the steering control input is used to minimize the cost function where Ky is the optimal feedback gain, M (t) is the finite preview control term, which are given as…”

“…Therefore, based on human comfort experiments published in [27], the absolute value of lateral acceleration is limited via velocitydependent constraints as…”

“…The proposed lateral index is based on experimental studies on human driving [27], which showed that values above ay,max definitely cause discomfort for human driving and also complicate the control of a vehicle. Note that ay,max decrease linearly as the velocity increases.…”

Real-time Performance and Safety Validation of an Integrated Vehicle Dynamic Control Strategy

“…where υ h,set is the user-set velocity of the host vehicle, a y,0 an acceptable medium comfort-level lateral acceleration constant (Xu et al (2015)), a h y,des is the desired lateral acceleration of the host vehicle based on human comfort, υ h,comf ort is the maximum velocity of the host vehicle giving comfort in curve (Kang et al (2008)), µ is the friction coefficient, g is the gravitational acceleration, υ hmax is the maximum speed of the host vehicle in term of mechanics, υ h,limit is maximum allowable velocity in curve in order to create safe lateral vehicle behavior by means of keeping the vehicle on the road without being driven away from the curve.…”

“…Similar to Cho et al (2011), the longitudinal index I longitudinal is determined by using a warning index and an inverse TTC. In this work we propose a novel lateral index (I lateral ) based on experimental studies on human driving (Xu et al (2015)), where the absolute value of lateral acceleration is limited via velocity-dependent constraints…”