Hierarchical Control for Vehicle Repositioning in Autonomous Mobility on Demand Systems

TL;DR

This paper introduces a hierarchical control strategy combining predictive and coverage control methods to optimize vehicle repositioning in autonomous mobility-on-demand systems, reducing passenger wait times and improving efficiency.

Contribution

It presents a novel two-layer hierarchical control approach that integrates data-driven predictive and coverage control algorithms for vehicle redistribution.

Findings

Improved vehicle distribution reduces passenger waiting times.

Simulation on Shenzhen's road network validates the approach's effectiveness.

Hierarchical control outperforms single-layer methods in efficiency.

Abstract

Balancing passenger demand and vehicle availability is crucial for ensuring the sustainability and effectiveness of urban transportation systems. To address this challenge, we propose a novel hierarchical strategy for the efficient distribution of empty vehicles in urban areas. The proposed approach employs a data-enabled predictive control algorithm to develop a high-level controller, which guides the inter-regional allocation of idle vehicles. This algorithm utilizes historical data on passenger demand and vehicle supply in each region to construct a non-parametric representation of the system, enabling it to determine the optimal number of vehicles to be repositioned or retained in their current regions without modeling the system. At the low level, a coverage control-based controller is designed to provide inter-regional position guidance, determining the desired road intersection each vehicle should target. With the objective of optimizing area coverage, it aligns the vehicle distribution with the demand across different districts within a single region. The effectiveness of the proposed method is validated through simulation experiments on the real road network of Shenzhen, China. The integration of the two layers provides better performance compared to applying either layer in isolation, demonstrating its potential to reduce passenger waiting time and answer more requests, thus promoting the development of more efficient and sustainable transportation systems.