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Adaptive Leading Cruise Control in Mixed Traffic
Considering Human Behavioral Diversity
Qun Wang, Haoxuan Dong, Fei Ju, Weichao Zhuang, Chen Lv, Liangmo Wang, and Ziyou Song
Abstract—This paper presents an adaptive leading cruise
control strategy for the connected and automated vehicle (CAV)
and first considers its impact on the following human-driven
vehicle (HDV) with diverse driving characteristics in the unified
optimization framework for improved holistic energy efficiency.
The car-following behaviors of HDV are statistically calibrated
using the Next Generation Simulation dataset. In a typical single-
lane car-following scenario where CAVs and HDVs share the
road, the longitudinal speed control of CAVs can substantially
reduce the energy consumption of the following HDV by avoiding
unnecessary acceleration and braking. Moreover, apart from the
objectives including car-following safety and traffic efficiency,
the energy efficiencies of both CAV and HDV are incorporated
into the reward function of reinforcement learning. The specific
driving pattern of the following HDV is learned in real-time
from historical speed information to predict its acceleration and
power consumption in the optimization horizon. A comprehensive
simulation is conducted to statistically verify the positive impacts
of CAV on the holistic energy efficiency of the mixed traffic flow
with uncertain and diverse human driving behaviors. Simulation
results indicate that the holistic energy efficiency is improved by
4.38 % on average.
I. INTRODUCTION
THE transportation sector, which consumes 25% of global
energy resources, is one of the main sources of green-
house gas emissions and air pollution [1]. Extensive efforts
have been made to improve vehicle efficiency and lower
emissions of on-road vehicles in response to the increasingly
stringent emission standards [2]–[4]. As a crucial technology
in saving energy consumed by vehicles, eco-driving has been
extensively discussed [5]–[9], with the core idea of adjusting
vehicle speed and maintaining an energy-efficient driving
style [10]. More recently, the development of connectivity
and automation technologies has provided another promising
opportunity to further cut down energy consumption through
the deployment of connected and automated vehicles (CAVs).
Qun Wang is with the Department of Mechanical Engineering, National
University of Singapore, Singapore 117575, Singapore, and also with the
School of Mechanical Engineering, Nanjing University of Science and Tech-
nology, Nanjing 210094, China (e-mail: wangqun@u.nus.edu).
Haoxuan Dong and Weichao Zhuang are with the School of Mechanical
Engineering, Southeast University, Nanjing 211189 , China (e-mail: dong-
haox@foxmail.com; wezhuang@seu.edu.cn).
Fei Ju and Liangmo Wang are with the School of Mechanical Engineering,
Nanjing University of Science and Technology, Nanjing 210094, China (e-
mail:jufei@njust.edu.cn; liangmo@njust.edu.cn).
Chen Lv is with the School of Mechanical and Aerospace Engi-
neering, Nanyang Technological University, Singapore 639798 (e-mail:
lyuchen@ntu.edu.sg).
Ziyou Song is with the Department of Mechanical Engineering, Na-
tional University of Singapore, Singapore 117575, Singapore (e-mail:
ziyou@nus.edu.sg).
Corresponding authors: Weichao Zhuang; Ziyou Song.
With the assistance of vehicle-to-anything (V2X) communica-
tions [11] and sensor fusion techniques [12], CAVs can take
advantage of the rich information to optimize their operations,
such as vehicle acceleration [13], motor torque regulation [14],
path planning [15], etc.
Despite some promising results indicating that CAVs can
save energy, the impacts of connectivity and autonomy on
the traffic efficiency and energy performance of neighboring
vehicles have not been extensively studied, while this type
of study can provide insights for policymakers and incentives
to further promote CAVs. For example, Joshua et al. [16]
analyzed the mobility and energetic impacts introduced by
CAVs’ deployment. Results demonstrate that the traffic flow
is improved with the increasing travel demand and decreasing
travel time. Fakhrmoosavi et al. [17] explored the influences
of a mixed traffic fleet on several aspects from a network
level, indicating that CAVs can enhance traffic safety, mobility,
and emission reduction of the traffic system. Zhao et al. [18]
assessed the impacts of CAVs under eight different testing
scenarios with a travel demand model and simulation results
indicate that the travel demand in Austin, Texas can increase
by at least 20%.
Moreover, it is anticipated that CAVs and human-driven ve-
hicles (HDVs) will co-exist on the same road in the near future
[19], [20]. Human drivers will still remain to be the majority
who take charge of vehicle operations for a long period. Hence,
it is imperative to develop eco-driving strategies for CAVs in
the mixed traffic flow in which CAVs frequently interact with
HDVs. Lu et al. [21] proposed an energy-efficient adaptive
cruise control model for electric CAVs in a mixed traffic flow.
Simulations are performed in a mixed single-lane traffic flow
with different market penetration rates of CAVs, indicating
that the proposed method exhibits a superior performance
in energy saving compared to other existing adaptive cruise
control and cooperative adaptive cruise control methods. Zhu
et al. [22] designed a novel model predictive control (MPC)
method to enhance energy efficiency and keep driving safety
for the CAV in a mixed traffic flow. An integrated data-driven
model of car-following is used in the MPC framework to
predict the behaviors of HDVs. Simulation results validate its
effectiveness in energy efficiency improvement and robustness.
Li et al. [23] developed a cooperative controller for CAVs
in a mixed traffic platoon based on multi-agent reinforcement
learning. Compared with MPC, the proposed strategy performs
better in dampening traffic oscillations and reducing energy
consumption. Ma et al. [24] investigated the energy-saving
potentials of the following human-driven platoon enabled by
eco-driving control of CAVs ahead. Especially, the influences
arXiv:2210.02147v1 [eess.SY] 5 Oct 2022