Multi-Objective Search: Algorithms, Applications, and Emerging Directions
Oren Salzman, Carlos Hernández Ulloa, Ariel Felner, Sven Koenig
TL;DR
This paper addresses the challenge of balancing multiple objectives in decision-making by surveying the MOS landscape, including exact, approximate, anytime, and dynamic variants, as well as extensions beyond deterministic MOS. It clarifies foundational notions (e.g., PF, dominance, and epsilon-approximation) and details algorithmic progress (MO-A*, NAMOA-dr, A^*pex, MVH/BO-DHs), along with practical toolbox applications in MO-MST, MO-MAPF, and CSP. The authors review emerging applications in automated design, multi-modal planning, and robotics, and identify open challenges such as scalability, dynamic environments, preference elicitation, cross-domain cross-fertilization, and benchmarks. The work highlights the practical significance of MOS for real-world systems, where trade-offs between time, cost, safety, and other criteria must be navigated, and argues for greater cross-community collaboration and benchmark development to accelerate progress.
Abstract
Multi-objective search (MOS) has emerged as a unifying framework for planning and decision-making problems where multiple, often conflicting, criteria must be balanced. While the problem has been studied for decades, recent years have seen renewed interest in the topic across AI applications such as robotics, transportation, and operations research, reflecting the reality that real-world systems rarely optimize a single measure. This paper surveys developments in MOS while highlighting cross-disciplinary opportunities, and outlines open challenges that define the emerging frontier of MOS
