Safety Analysis of a Modified Cooperative Adaptive Cruise Control Algorithm Accounting for Communication Delay

Abstract

Cooperative adaptive cruise control (CACC) is a promising technology to improve traffic efficiency and enhance road safety. In this paper, a modified CACC control model considering the communication time delay is proposed, which is used to investigate the longitudinal safety impacts of the communication time delay to the CACC platoon. Then, the communication time delay model is integrated into the CACC model to simulate the realistic information transfer process in the CACC platoon. Then a microscopic CACC platoon simulation is designed and conducted to verify the feasibility and reliability of the modified CACC control algorithm. The obtained results reveal that the modified CACC control algorithm can not only reduce about 96.6% of inter-vehicle spacing error, but also enhance the vehicles’ ability to sense the upstream traffic changes. Furthermore, to quantitatively analyze the longitudinal safety influence of the time delay caused by representative communication systems, sensitivity analysis experiments of headway time were designed and conducted. In the sensitivity analysis, the time exposed time-to-collision (TET) and the time-integrated time-to-collision (TIT) were introduced as the key performance indicators (KPIs) to quantify the rear-end collision risks. Sensitivity analysis results demonstrate that the performance of the CACC platoon is strictly related to the applied wireless communication style. Furthermore, the CACC system supported by the 5th generation (5G) communication system shows great advantages in narrowing the minimal headway time gap and reducing the rear-end collision risks.

Connected and Autonomous Vehicles and Infrastructures: A Literature Review

“…GNSS is a satellite-based system and follows a trilateration procedure to localize and navigate a vehicle [ 16 , 65 ]. CACC integrates dedicated short-range communication (DSRC) technologies to establish vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication [ 66 ]. The recently developed vehicle-to-everything (V2X) technology is gaining momentum, being more advantageous in improving safety.…”

“…The integration of DSRC into ACC enhances its performance by establishing communications (i.e., V2V, V2I) with surrounding, leading it to CACC. This longitudinal control strategy in a traffic platoon maintains the shortest possible distance between two vehicles and stabilized speed to improves safety [ 66 ]. GNSS technology (Fig.…”

“…This controller improves comfort without considering the reduced performance. Liu et al [ 66 ] integrated advanced CACC algorithm in a platoon and observed the improved platooning performance with the enhancement of string stability. Longitudinal stability and the effects of adverse weather on V2V in this cooperative system was not taken into account.…”

An Algorithm for Detecting Collision Risk between Trucks and Pedestrians in the Connected Environment

“…Collisions between workers and equipment in port yards are similar to pedestrian-vehicle crashes on roads, which constitute a leading concern in traffic safety. Multiple algorithm-based technologies have been developed to avoid collisions, including the forward crash warning system [2][3][4][5]. e concept of time-to-collision (TTC), which is used frequently in these algorithms, is defined in relation to the preceding and following vehicles [6].…”

A Safety Reinforced Cooperative Adaptive Cruise Control Strategy Accounting for Dynamic Vehicle-to-Vehicle Communication Failure

“…Furthermore, in traffic accidents caused by inattentiveness, almost 50% of them are directly triggered by drivers’ distractions. In order to reduce drivers’ physical and mental burden, both academia and industry have shown great interest in seeking robust autonomous vehicles to substitute the error-prone human driving [ 9 , 10 ]. Therefore, developing a reliable autonomous vehicle control system that replicates the desired driving behaviors to avoid traffic collisions is still an ongoing research challenge [ 11 ].…”