Collaborative Robotic Manipulation: A Use Case of Articulated Objects in Three-dimensions with Gravity

TL;DR

This paper presents a framework enabling collaborative robots to manipulate articulated objects in 3D space while accounting for gravity, improving robustness and adaptability in human-robot shared environments.

Contribution

It introduces a novel integration of gravity modeling into robotic manipulation planning, enhancing robustness in collaborative tasks involving articulated objects.

Findings

Gravity-aware planning improves manipulation robustness.

Different gravity modeling complexities affect performance and accuracy.

Framework validated successfully in simulation with a dual-arm robot.

Abstract

This paper addresses two intertwined needs for collaborative robots operating in shop-floor environments. The first is the ability to perform complex manipulation operations, such as those on articulated or even flexible objects, in a way robust to a high degree of variability in the actions possibly carried out by human operators during collaborative tasks. The second is encoding in such operations a basic knowledge about physical laws (e.g., gravity), and their effects on the models used by the robot to plan its actions, to generate more robust plans. We adopt the manipulation in three-dimensional space of articulated objects as an effective use case to ground both needs, and we use a variant of the Planning Domain Definition Language to integrate the planning process with a notion of gravity. Different complexity levels in modelling gravity are evaluated, which trade-off model faithfulness and performance. A thorough validation of the framework is done in simulation using a dual-arm Baxter manipulator.