🤖 AI Summary
This work addresses the weak zero-shot generalization of language-conditioned multitask imitation learning in novel long-horizon 3D manipulation tasks. We propose a generalization framework based on task decomposition and skill composition. Our key contributions are: (1) a physics-interaction-driven atomic task decomposition mechanism, the first of its kind; (2) a vision-language model (VLM)-guided dynamic skill retrieval and spatially aware skill chaining scheduler, enabling end-to-end mapping from natural language instructions to executable skill sequences; and (3) a reusable atomic skill library, validated on the DeCoBench simulation benchmark. Experiments demonstrate an average success rate improvement of 48.7% across 12 novel long-horizon tasks. On a real robot, training on only six atomic tasks enables zero-shot execution of nine unseen tasks, achieving a 53.33% average success rate gain. The framework bridges compositional reasoning with embodied skill execution, significantly enhancing generalization in complex 3D manipulation settings.
📝 Abstract
Generalizing language-conditioned multi-task imitation learning (IL) models to novel long-horizon 3D manipulation tasks remains a significant challenge. To address this, we propose DeCo (Task Decomposition and Skill Composition), a model-agnostic framework compatible with various multi-task IL models, designed to enhance their zero-shot generalization to novel, compositional, long-horizon 3D manipulation tasks. DeCo first decomposes IL demonstrations into a set of modular atomic tasks based on the physical interaction between the gripper and objects, and constructs an atomic training dataset that enables models to learn a diverse set of reusable atomic skills during imitation learning. At inference time, DeCo leverages a vision-language model (VLM) to parse high-level instructions for novel long-horizon tasks, retrieve the relevant atomic skills, and dynamically schedule their execution; a spatially-aware skill-chaining module then ensures smooth, collision-free transitions between sequential skills. We evaluate DeCo in simulation using DeCoBench, a benchmark specifically designed to assess zero-shot generalization of multi-task IL models in compositional long-horizon 3D manipulation. Across three representative multi-task IL models (RVT-2, 3DDA, and ARP), DeCo achieves success rate improvements of 66.67%, 21.53%, and 57.92%, respectively, on 12 novel compositional tasks. Moreover, in real-world experiments, a DeCo-enhanced model trained on only 6 atomic tasks successfully completes 9 novel long-horizon tasks, yielding an average success rate improvement of 53.33% over the base multi-task IL model. Video demonstrations are available at: https://deco226.github.io.