A Survey of Motion Planning Methods for Cooperative Lane Changes

Abstract

Cooperative lane change is a safety-critical motion-planning problem for connected and automated vehicles (CAVs), because the lane-changing vehicle must coordinate its lateral and longitudinal motion with surrounding vehicles in a shared and dynamically evolving traffic space. This survey reviews cooperative lane-change motion planning from the perspective of the dominant planning mechanism and classifies existing methods into five categories: gap-generation-based planners create or enlarge insertion spaces through coordinated longitudinal motion; joint-optimization-based planners optimize coupled multi-vehicle trajectories under unified objectives and constraints; priority-based planners determine passing orders, target gaps, or lane-change opportunities before trajectory generation; formation-regulation-based planners reshape platoons or vehicle groups through splitting, merging, sparsification, and recovery; and intention-and-response-aware planners infer and adapt to yielding, competitive, or cooperative responses. Beyond cataloguing representative studies, the survey compares their assumptions, coordination scope, computational burden, and robustness. The comparison reveals a recurring tension between interaction fidelity, online tractability, and the strength of safety guarantees, and identifies open problems in mixed-traffic robustness, scalable coordination, and reproducible evaluation.