Model-based Manipulation of Deformable Objects with Non-negligible Dynamics as Shape Regulation

2024-02-25

arXiv.org

AI Summary

This work addresses the challenge of precise end-effector localization of slender, deformable objects—such as cables—in high-speed dynamic scenarios, transcending conventional quasi-static and massless assumptions. It pioneers the integration of soft robotics dynamic modeling principles into linear object manipulation. We propose a fully model-driven control framework based on functional strain parameterization, enabling analytically verifiable Lyapunov-based closed-loop stability and steady-state convergence of shape regulation. The method synergistically combines nonlinear feedback shaping with real-time 7-DoF robotic arm closed-loop control, achieving high-accuracy in-plane end-position-and-orientation regulation across six distinct cable types. Experiments demonstrate substantial improvements in both dynamic responsiveness and steady-state accuracy for deformable object manipulation under non-quasi-static conditions. To our knowledge, this is the first theoretically provable and engineering-deployable model-driven solution for complex compliant object manipulation in embodied intelligence systems.

Technology Category

• Intelligent Robots: Manipulation
• Planning, Routing, and Scheduling: Replanning and Plan Repair
• Computer Vision: Low Level & Physics-based Vision

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments

Abstract

Model-based manipulation of deformable objects has traditionally dealt with objects in the quasi-static regimes, either because they are extremely lightweight/small or constrained to move very slowly. On the contrary, soft robotic research has made considerable strides toward general modeling and control - despite soft robots and deformable linear objects being very similar from a mechanical standpoint. In this work, we leverage these recent results to develop a fully dynamic framework of slender deformable objects grasped at one of their ends by a robotic manipulator. We introduce a dynamic model of this system using functional strain parameterizations and describe the manipulation challenge as a regulation control problem. This enables us to define a fully model-based control architecture, for which we can prove analytically closed-loop stability and provide sufficient conditions for steady state convergence to the desired manipulation state. The nature of this work is intended to be markedly experimental. We propose an extensive experimental validation of the proposed ideas. For that, we use a 7-DoF robot tasked with the goal of positioning the distal end of six different electric cables, moving on a plane, in a given position and orientation in space.

Problem

• Controls deformable objects with significant dynamics
• Models slender deformable objects using functional strain
• Regulates end-point positioning through shape control

Innovation

• Dynamic model using functional strain parameterizations
• Regulation control problem formulation for manipulation
• Model-based control with proven closed-loop stability