A New Car Following Model:Comprehensive Optimal Velocity Model

In this paper, we present a new ear-following model, i.e. comprehensive optimal velocity model （COVM）, whose optimal velocity function not only depends on the following distance of the preceding vehicle, but also depends on the velocity difference with preceding vehicle. Simulation results show that COVM is an improvement over the previous ones theoretically. Then, the stability condition of the model is obtained by the linear stability analysis, which has shown that the model could obtain a bigger stable region than previous models in the phase diagram. Through the nonlinear analysis, the Burgers, Korteweg-de Vries （KdV） and modified KdV （mKdV） equations are derived for the triangular shock wave, the soliton wave, and the kink-antikink soliton wave. At the same time, numerical simulations are also carried out to show that the model could simulate these density waves.

Solid angle car following model

Existing traffic flow models give little consideration on vehicle sizes. We introduce the solid angle into car-following theory, taking the driver’s perception of the leading vehicle’s size into account. The solid angle and its change rate are applied as inputs to the novel model. A nonlinear stability analysis is performed to analyze the asymmetry of the model and the size effect of the leading vehicle, and the modified Korteweg–de Vries equation is derived. The solid angle model can explain complex traffic characteristics and provide an important basis for modeling nonlinear traffic phenomena.

Integrated adaptive dynamic surface car-following control for nonholonomic autonomous electric vehicles

In this paper,the car-following control problem of nonholonomic autonomous electric vehicles in the curved highway is studied.Owing to the fact that the nonholonomic autonomous electric vehicles have the features of strong coupling,parametric uncertainties,nonlinearities and external disturbances,a novel integrated adaptive car-following control system is constructed to supervise the longitudinal and lateral motions of vehicles.Firstly,an adaptive fuzzy dynamic surface car-following control strategy is presented to determine a vector of total forces and torque of autonomous electric vehicles,which can guarantee the uniform ultimate boundedness of close-loop control signals.Then,an optimal tire forces distribution law is proposed to dynamically allocate the desired coupled tire longitudinal and lateral forces in real-time.Finally,simulation results illustrate the effectiveness and robustness of the proposed car-following control approach.

Optimal velocity functions for car-following models

The integral part of the optimal velocity car-following models is the optimal velocity function (OVF), which can be derived from measured velocity-spacing data. This paper discusses several characteristics of the OVF and presents regression analysis on two classical datasets, the Lincoln and Holland tunnels, with different possible OVFs. The numerical simulation of the formation of traffic congestion is conducted with three different heuristic OVFs, demonstrating that these functions give results similar to those of the famous Bando OVF (Bando et al., 1995). Also an alternative method is present for determining the sensitivity and model parameters based on a single car driving to a fixed barrier.

Application of singular perturbation method in analyzing traffic density waves

Car following model is one of microscopic models for describing traffic flow. Through linear stability analysis, the neutral stability lines and the critical points are obtained for the different types of car following models and two modified models. The singular perturbation method has been used to derive various nonlinear wave equations, such as the Kortewegde-Vries （KdV） equation and the modified Korteweg-de-Vries （mKdV） equation, which could describe different density waves occurring in traffic flows under certain conditions. These density waves are mainly employed to depict the formation of traffic jams in the congested traffic flow. The general soliton solutions are given for the different types of car following models, and the results have been used to the modified models efficiently.

Design of multi-vehicle ad hoc experiment system based on VANets

Vehicular ad hoc networks(VANets) experiment system is studied.Configuration,characteristics and research fields of VANets are introduced briefly.According to the characteristics of VANets,key modules that multi-vehicle ad hoc experiment system needs are designed,and each module's function and practice requirement is analyzed.The reliability of experiment system is tested primarily using three experiment scenes of multi-vehicle ad hoc network,car following and wireless positioning.The experiment result shows that multi-vehicle ad hoc experiment system has the capability of the correlated experiment of VANets.