# Analysis of Operational Effects of Bus Lanes with Intermittent Priority with Spatio-Temporal Clear Distance and CAV Platoon Coordinated Lane Changing in Intelligent Transportation Environment

## TL;DR

This paper introduces a new method for managing bus lanes with intermittent priority using connected and automated vehicles to improve traffic efficiency.

## Contribution

The novel BLIP-ST method and CAV control strategy enhance road traffic efficiency by coordinating lane changes with CAV platoons.

## Key findings

- CAV-sharing bus lanes significantly improve traffic efficiency, especially at medium CAV penetration rates.
- BLIP-ST achieves best efficiency at medium CAV penetration rates due to optimal resource utilization.
- CAV platoon coordination improves road speed by 8–19% compared to single CAV coordination.

## Abstract

Bus lanes with intermittent priority (BLIP) are designed to optimize road resource allocation. The advent of connected and automated vehicles (CAVs) promotes the implementation of BLIP. However, it is crucial to find an effective method to intermittently grant right-of-way to CAVs. In this paper, we introduce a BLIP method with spatio-temporal clear distance (BLIP-ST) and a CAV control method in an intelligent transportation environment. When CAVs access BLIP-ST, the constraints of the moving gap between buses are considered. When CAVs leave BLIP-ST, coordination with the nearest CAV platoon on the adjacent lane is considered to cope with situations where CAVs cannot find the appropriate space. Then, the proposed method was simulated by an open boundary cellular automaton model. The results showed that with the same inflow, a CAV-sharing bus lane could significantly improve road traffic efficiency, and it is the most significant when the CAV penetration rate is medium, with the average road speed increasing from 6.67 km/h to 30.53 km/h. Meanwhile, when the CAV penetration rate is medium, BLIP-ST operates with the best efficiency at different strategies. This was due to the fact that when the penetration rate is too high, BLIP-ST is excessively occupied, which affects public transportation priority. When the penetration rate is too low, BLIP-ST cannot be fully utilized. In addition, regardless of the penetration rate of CAV, CAV platoon collaborative lane changing is better than single CAV collaborative lane changing in terms of improving road traffic efficiency and can increase the average road speed by 8–19%.