🤖 AI Summary
Desktop rearrangement tasks pose significant challenges due to highly entangled initial and goal object configurations, non-monotonicity, and the need for long-horizon, coordinated multi-arm planning.
Method: This paper proposes SDAR—a tightly coupled task-and-motion planning framework—built upon dependency-driven task decomposition, hierarchical synchronized dual-arm motion planning, and a GPU-accelerated SIMD motion planner. It introduces a novel dependency graph decomposition algorithm to enable temporal coordination and joint optimization of multi-arm actions.
Contribution/Results: SDAR achieves 100% planning success rate in strongly entangled scenarios, substantially outperforming existing state-of-the-art methods. The framework is rigorously validated on two physical UR-5e robotic arms, demonstrating robust real-world performance and reliability.
📝 Abstract
We propose Synchronous Dual-Arm Rearrange- ment Planner (SDAR), a task and motion planning (TAMP) framework for tabletop rearrangement, where two robot arms equipped with 2-finger grippers must work together in close proximity to rearrange objects whose start and goal config- urations are strongly entangled. To tackle such challenges, SDAR tightly knit together its dependency-driven task planner (SDAR-T) and synchronous dual-arm motion planner (SDAR- M), to intelligently sift through a large number of possible task and motion plans. Specifically, SDAR-T applies a simple yet effective strategy to decompose the global object dependency graph induced by the rearrangement task, to produce more optimal dual-arm task plans than solutions derived from optimal task plans for a single arm. Leveraging state-of-the-art GPU SIMD-based motion planning tools, SDAR-M employs a layered motion planning strategy to sift through many task plans for the best synchronous dual-arm motion plan while ensuring high levels of success rate. Comprehensive evaluation demonstrates that SDAR delivers a 100% success rate in solving complex, non-monotone, long-horizon tabletop rearrangement tasks with solution quality far exceeding the previous state- of-the-art. Experiments on two UR-5e arms further confirm SDAR directly and reliably transfers to robot hardware.