Controlling soft continuum manipulator arms is difficult due to their infinite degrees of freedom, nonlinear material properties, and large deflections under loading. This paper presents a data-driven approach to identifying soft manipulator models that enables consistent control under variable loading conditions. This is achieved by incorporating loads into a linear Koopman operator model as states and estimating their values online via an observer within the control loop. Using this approach, real-time, fully autonomous control of a pneumatically actuated soft continuum manipulator is achieved. In several trajectory following experiments, this controller is shown to be more accurate and precise than controllers based on models that are unable to explicitly account for loading. The manipulator also successfully performs pick and place of objects with unknown mass, demonstrating the efficacy of this approach in executing real-world manipulation tasks.
DK-RRT: Deep Koopman RRT for Collision-Aware Motion Planning of Space Manipulators in Dynamic Debris Environments
University of California, Irvine（加州大学尔湾分校）；Illinois Institute of Technology（伊利诺伊理工学院）；University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；University of California, Davis（加州大学戴维斯分校）；University of California, Berkeley（加州大学伯克利分校）
Aerial robotic systems have raised emerging interests in recent years. In this article, we propose a novel aerial manipulator system that is significantly different from conventional aerial discrete manipulators: An Aerial Continuum Manipulator (AeCoM). The AeCoM compactly integrates a quadrotor with a tendon-driven continuum robotic manipulator. Due to the compact design and the payload bearing ability of tendon-driven continuum robotic arms, the proposed system solved the conflict between payload capacity and dexterity lying in conventional aerial manipulators. Two contributions are made in …
Laboratoire des Sciences du Numérique de Nantes (LS2N)（南特数字科学实验室）；Innopolis University（因诺波利斯大学）；IMT Atlantique Nantes（大西洋矿业电信学院南特校区）；Centre National de la Recherche Scientifique (CNRS)（法国国家科学研究中心）
The paper focuses on the stiffness analysis of multi-link serial planar manipulators, which may demonstrate nonlinear stiffness behavior under the compressive loading. Two important cases are considered, where the manipulator has either a straight or non-straight initial configuration. It was proved that in the first case the loading may cause the buckling if it exceeds some critical value, and the manipulator suddenly changes its straight shape and stiffness properties. For computing this critical force, a general eigenvalue-based technique was proposed that can be applied to any multi-link s…
Laboratoire des Sciences du Numérique de Nantes (LS2N)（南特数字科学实验室）；IMT Atlantique（大西洋国立高等矿业电信学校）；Centre National de la Recherche Scientifique (CNRS)（法国国家科学研究中心）
The paper focuses on the stiffness modeling of a new type of compliant manipulator and its non-linear behavior while interacting with the environment. The manipulator under study is a serial mechanical structure composed of dualtriangle segments. The main attention is paid to the initial straight configuration which may suddenly change its shape under the loading. It was discovered that under the external loading such manipulator may have six equilibrium configurations but only two of them are stable. In the neighborhood of these configurations, the manipulator behavior was analyzed using the …
Kinetostatics and Particle-Swarm Optimization of Vehicle-Mounted Underactuated Metamorphic Loading Manipulators
Institute for Robotics Research（机器人研究所）；Centre for Robotics Research（机器人研究中心）；Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR)（新加坡制造技术研究所，科技研究局（A*STAR））
Institut de Recherche en Communications et Cybernetique de Nantes（南特通信与控制论研究所）；Ecole des Mines de Nantes（南特国立高等矿业学校）；University of Agder（阿格德大学）
The paper is devoted to the compliance errors compensation for parallel manipulators under external loading. Proposed approach is based on the non-linear stiffness modeling and reduces to a proper adjusting of a target trajectory. In contrast to previous works, in addition to compliance errors caused by machining forces, the problem of assembling errors caused by inaccuracy in the kinematic chains is considered. The advantages and practical significance of the proposed approach are illustrated by examples that deal with groove milling with Orthoglide manipulator.
Dynamic Neural Koopman Distillation for Fast Robot Control Using Diffusion Models
Department of Electrical and Computer Engineering, National University of Singapore（国立新加坡大学电子与计算机工程系）；Department of Electrical and Computer Engineering, Carnegie Mellon University（卡内基梅隆大学电子与计算机工程系）；Robotics and Autonomous Systems Thrust, The Hong Kong University of Science and Technology（香港科学与技术大学机器人与自主系统方向）
The Chinese University of Hong Kong（香港中文大学）；Southern University of Science and Technology（南方科技大学）；Shenzhen Research Institute of The Chinese University of Hong Kong（香港中文大学深圳研究院）
Recently Koopman operator has become a promising data-driven tool to facilitate real-time control for unknown nonlinear systems. It maps nonlinear systems into equivalent linear systems in embedding space, ready for real-time linear control methods. However, designing an appropriate Koopman embedding function remains a challenging task. Furthermore, most Koopman-based algorithms only consider nonlinear systems with linear control input, resulting in lousy prediction and control performance when the system is fully nonlinear with the control input. In this work, we propose an end-to-end deep le…
Provably Safe Trajectory Generation for Manipulators Under Motion and Environmental Uncertainties
Hong Kong Center for Construction Robotics, The Hong Kong University of Science and Technology（香港建设机器人中心，香港理工大学）；Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong（机械与自动化工程系，中国香港大学）；Department of Electronic Engineering, The Chinese University of Hong Kong（电子工程系，中国香港大学）；Shenzhen Key Laboratory of Robotics Perception and Intelligence and the Department of Electronic and Electrical Engineering at Southern University of Science and Technology（深圳机器人感知与智能重点实验室和南方科技大学电子与电气工程系）；Department of Electronic Engineering at The Chinese University of Hong Kong（电子工程系，中国香港大学）
A Modular, Tendon Driven Variable Stiffness Manipulator with Internal Routing for Improved Stability and Increased Payload Capacity
National Robotarium（国家机器人研究院）；Heriot Watt University（赫瑞瓦特大学）；Institute for Integrated Micro and Nano Systems（集成微纳系统研究所）；University of Edinburgh（爱丁堡大学）；Tough Cyberphysical AI Research Center (TCPAI)（硬核赛博物理人工智能研究中心）；Tohoku University（东北大学）；Senai Cimatec（塞奈西马泰克）
Sensor-Space Based Robust Kinematic Control of Redundant Soft Manipulator by Learning
Department of Mechanical and Aerospace Engineering, The University of Manchester, Manchester, United Kingdom（机械与航空航天工程系，曼彻斯特大学，英国曼彻斯特）；Department of Electrical and Electronic Engineering, The University of Manchester, Manchester, United Kingdom（电气与电子工程系，曼彻斯特大学，英国曼彻斯特）
Generalized Momenta-Based Koopman Formalism for Robust Control of Euler-Lagrangian Systems
Department of Mechanical Engineering, Indian Institute of Science（机械工程系，印度科学研究院）；Robert Bosch Centre for Cyber-Physical Systems, Indian Institute of Science（网络物理系统研究中心，印度科学研究院）
Dept. of Electrical and Computer Engineering, University of California, Riverside（加州大学河滨分校电气与计算机工程系）；Dept. of Mechanical and Aerospace Engineering, University of California San Diego（加州大学圣地亚哥分校机械与航空航天工程系）；Dept. of Planning and Control, Zoox Inc.（Zoox公司规划与控制部）；Dept. of Mechanical Engineering, University of Michigan（密歇根大学机械工程系）；Dept. of Mechanical Engineering, Yale University（耶鲁大学机械工程系）；Dept. of Mechanical Engineering, Northwestern University（西北大学机械工程系）；Institute of AI Industry Research (AIR), Tsinghua University（清华大学人工智能产业研究院）
Dynamic robotic cloth folding with efficient Koopman operator-based model predictive control
Istituto Italiano di Tecnologia（意大利技术研究院）；Institut de Robòtica i Informàtica Industrial（机器人与信息技术研究所）；MaLGa Center, DIBRIS, Università degli Studi di Genova（MaLGa中心，DIBRIS，热那亚大学）
