Fast and Memory Efficient Multimodal Journey Planning with Delays

Abstract

State-of-the-art multimodal journey-planning algorithms, such as ULTRA, have recently been adapted to account for delays. In this work, we extend this approach to be more memory-efficient, faster, and accurate. We also adapt this framework to other state-of-the-art algorithms, like CSA and RAPTOR. We demonstrate a speedup of 1.9-4.2x over existing algorithms in the single-objective search (earliest arrival time). In the bicriteria setting, we achieve competitive speedup results but greater accuracy. We also find that our method scales much better as the delay buffer Delta increases.

v4: revised manuscript incorporating reviewer feedback (Related Work restructure, temporal-planning baselines, Bez 2020 thesis acknowledgment, equation relocation); style switched to the AAAI 2026 format