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arXiv · 2611.07726

Dual-Arm Tabletop Rearrangement with Movable Stacking and Gap-Aware Push Transfers

Mohammadreza Firoozalizadeh·Zakiye Rostamirad·Arman Barghi·Ahmad Kalhor·Mohammadreza Nayeri·Mehdi Tale Masouleh
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Abstract

Object rearrangement in cluttered tabletop scenes is challenging, especially in wide workspaces where dual-arm systems improve coverage and efficiency. Limited free space often necessitates buffering, while objects near or across the shared reachability region of the manipulators must be transferred under careful coordination to avoid inter-arm collisions. Conventional inter-arm transfer typically relies on a fixed handoff configuration, which constrains where and how objects are exchanged, enforces spatiotemporal synchronization of the arms, and reduces flexibility in dense layouts. This paper presents a dual-arm rearrangement framework that combines movable stacking with Gap-Aware Push Transfer for asynchronous cross-boundary exchange. The method scans the shared boundary to identify collision-free transfer gaps, places an object near a selected crossing point, and then pushes it into the receiving workspace without requiring simultaneous interaction between the two arms. A joint Monte Carlo Tree Search (MCTS)-based planner coordinates both manipulators while reasoning over buffering and transfer decisions, and execution cost is used after planning to assess the resulting plan. Experiments show that the proposed method shortens joint execution sequences and becomes increasingly advantageous over a fixed handoff baseline as scene density increases, achieving lower execution cost in denser scenes while remaining competitive in lighter ones.

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Mohammadreza Firoozalizadeh, Zakiye Rostamirad, Arman Barghi, Ahmad Kalhor, Mohammadreza Nayeri, Mehdi Tale Masouleh. 2026-11-05. Dual-Arm Tabletop Rearrangement with Movable Stacking and Gap-Aware Push Transfers. https://doi.org/10.1109/icee70628.2026.11710769

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