Learning from Demonstration (LfD) stands as an efficient framework for imparting human-like skills to robots. Nevertheless, designing an LfD framework capable of seamlessly imitating, generalizing, and reacting to disturbances for long-horizon manipulation tasks in dynamic environments remains a challenge. To tackle this challenge, we present Logic-LfD, which combines Task and Motion Planning (TAMP) with an optimal control formulation of Dynamic Movement Primitives (DMP), allowing us to incorporate motion-level via-point specifications and to handle task-level variations or disturbances in dynamic environments. We conduct a comparative analysis of our proposed approach against several baselines, evaluating its generalization ability and reactivity across three long-horizon manipulation tasks. Our experiment demonstrates the fast generalization and reactivity of Logic-LfD for handling task-level variants and disturbances in long-horizon manipulation tasks.
Overview of Logic-LfD. Arrows refer to action primitives encoded with the proposed DMP variant (LQT-CP). The template task starts from L0 and ends at goal G. L0 → L1 → L2 → G illustrates the task-level demonstration. For a new task starting from L0 prime, a fixed sequential execution of actions primitives encoded by DMPs (green arrows) cannot transition from L0 prime to the goal state G. Typical TAMP solvers find the action skeleton from L0 prime to G from scratch (grey dashed long arrow). Instead, Logic-LfD tries to reach both task goal G and all other states (blue arrows) in the demonstration in parallel to find a feasible plan L0 prime → L1 connecting L0 prime to the demonstration trajectory within the minimum time. It then merges the new plan with the corresponding segmentation of the demonstration L1 → L2 → G, thus accomplishing the new task faster than classical TAMP solvers.
In the following, we illustrate videos of reactive task and motion planning with Logic-LfD for solving tasks under various levels of disturbances.
Level 1: Motion-level Variant/Disturbance: Blocks are subjected to disturbances in different positions, while logical states remain consistent with the original or expected conditions;
Level 2: Slight Task-level Variant/Disturbance: Blocks undergo disturbances, resulting in a different logical state. This logical state aligns with that seen in the demonstration for the template task;
Level 3: Severe Task-level Variant/Disturbance: Blocks are disturbed to a novel and previously unseen logical state in the demonstration;
Level 4: Extreme Task-level Variant/Disturbance: A new block is introduced into the scene that significantly influences the execution of the initial plan to achieve the target goal.
Level 1 Disturbance
Level 2 Disturbance
Level 3 Disturbance
Level 4 Disturbance
Level 1 Disturbance
Level 2 Disturbance
Level 3 Disturbance
Level 4 Disturbance
Level 1 Disturbance
Level 2 Disturbance
Level 3 Disturbance
Level 4 Disturbance
Block Stacking with L1 and L3 Disturbance
Block Stacking with L2 and L4 Disturbance
@article{zhang2024logic,
title={Logic Learning from Demonstrations for Multi-step Manipulation Tasks in Dynamic Environments},
author={Zhang, Yan and Xue, Teng and Razmjoo, Amirreza and Calinon, Sylvain},
journal={IEEE Robotics and Automation Letters},
year={2024},
volume={9},
number={8},
pages={7214-7221},
doi={10.1109/LRA.2024.3418276}
}