A Null Space Compliance Approach for Maintaining Safety and Tracking Performance in Human-Robot Interactions
Department of Electrical and Computer Engineering, Western University（电气与计算机工程系，西方大学）；School of Artificial Intelligence and Automation, Huazhong University of Science and Technology（人工智能与自动化学院，华中科技大学）
In recent years, the focus on developing robot manipulators has shifted towards prioritizing safety in Human-Robot Interaction (HRI). Impedance control is a typical approach for interaction control in collaboration tasks. However, such a control approach has two main limitations: 1) the end-effector (EE)'s limited compliance to adapt to unknown physical interactions, and 2) inability of the robot body to compliantly adapt to unknown physical interactions. In this work, we present an approach to address these drawbacks. We introduce a modified Cartesian impedance control method combined with a Dynamical System (DS)-based motion generator, aimed at enhancing the interaction capability of the EE without compromising main task tracking performance. This approach enables human coworkers to interact with the EE on-the-fly, e.g. tool changeover, after which the robot compliantly resumes its task. Additionally, combining with a new null space impedance control method enables the robot body to exhibit compliant behaviour in response to interactions, avoiding serious injuries from accidental contact while mitigating the impact on main task tracking performance. Finally, we prove the passivity of the system and validate the proposed approach through comprehensive comparative experiments on a 7 Degree-of-Freedom (DOF) KUKA LWR IV+ robot.
Physical Human-Robot Interaction (pHRI) task involves tight coupling between safety constraints and compliance with human intentions. In this paper, a novel switched model reference admittance controller is developed to maintain compliance with the external force while upholding safety constraints in the workspace for an n-link manipulator involved in pHRI. A switched reference model is designed for the admittance controller to generate the reference trajectory within the safe workspace. The stability analysis of the switched reference model is carried out by an appropriate selection of the Co…
Collaborative robots should ideally use low torque actuators for passive safety reasons. However, some applications require these collaborative robots to reach deep into confined spaces while assisting a human operator in physically demanding tasks. In this paper, we consider the use of in-situ collaborative robots (ISCRs) that balance the conflicting demands of passive safety dictating low torque actuation and the need to reach into deep confined spaces. We consider the judicious use of bracing as a possible solution to these conflicting demands and present a modeling framework that takes int…
SAC-Loco: Safe and Adjustable Compliant Quadrupedal Locomotion
Department of Electrical and Computer Engineering, National University of Singapore（新加坡国立大学电子与计算机工程系）；School of Computer Science and Engineering, Sun Yat-sen University（中山大学计算机科学与工程学院）
Behavior Trees in Functional Safety Supervisors for Autonomous Vehicles
Institut de Robòtica i Informàtica Industrial (CSIC-UPC)（机器人与工业信息研究所（西班牙国家研究委员会-加泰罗尼亚理工大学））；Universitat Politècnica de Catalunya-BarcelonaTech（加泰罗尼亚理工大学（巴塞罗那科技学院））；Renault Group（雷诺集团）
本文提出一种基于行为树并符合 ISO 26262 的实时功能安全监督架构，用于在 SAE 3 级自动驾驶车辆中检测危险并确保安全合规。
The ISO 26262 is currently the dominant standard for assuring functional safety of electrical and electronic systems in the automotive industry. The Functional Safety Concept (FSC) subphase in the standard requires the Preliminary Architectural Assumptions (PAA) for allocation of functional safety requirements (FSRs). This paper justifies the need for, and defines a process ATRIUM, for consistent design of the PAA. ATRIUM is subsequently applied in an industrial case study for a function enabling highly automated driving at one of the largest heavy vehicle manufacturers in Europe, Scania CV AB…
Embedding ISO 10218 Safety Compliance in Robots via Control Barrier Functions for Human-Robot Collaboration
Dept. of Electrical and Information Engineering, Polytechnic of Bari（巴里理工大学电气与信息工程系）；Dipartimento di Ingegneria Meccanica e Industriale, University of Brescia（布雷西亚大学机械与工业工程系）；Institute of Intelligent Industrial Technologies and Systems, National Research Council of Italy, STIIMA-CNR（意大利国家研究委员会智能工业技术与系统研究所）
School of Computer Science, Carnegie Mellon University（卡内基梅隆大学计算机科学学院）
Robots of the future are going to exhibit increasingly human-like and super-human intelligence in a myriad of different tasks. They are also likely going to fail and be incompliant with human preferences in increasingly subtle ways. Towards the goal of achieving autonomous robots, the robot learning community has made rapid strides in applying machine learning techniques to train robots through data and interaction. This makes the study of how best to audit these algorithms for checking their compatibility with humans, pertinent and urgent. In this paper, we draw inspiration from the AI Safety…
Beijing Research Institute of UBTECH Robotics（优必选机器人北京研究院）；Tsinghua University（清华大学）
The hierarchical quadratic programming (HQP) is commonly applied to consider strict hierarchies of multi-tasks and robot's physical inequality constraints during whole-body compliance. However, for the one-step HQP, the solution can oscillate when it is close to the boundary of constraints. It is because the abrupt hit of the bounds gives rise to unrealisable jerks and even infeasible solutions. This paper proposes the mixed control, which blends the single-axis model predictive control (MPC) and proportional derivate (PD) control for the whole-body compliance to overcome these deficiencies. T…
The widespread adoption of autonomous systems depends on providing guarantees of safety and functional correctness, at both design time and runtime. Information about the extent to which functional requirements can be met in combination with non-functional requirements (NFRs) -- i.e. requirements that can be partially complied with -- , under dynamic and uncertain environments, provides opportunities to enhance the safety and functional correctness of systems at design time. We present a technique to formally define system attributes that can change or be changed to deal with dynamic and uncer…
Model-less Active Compliance for Continuum Robots using Recurrent Neural Networks
Queensland University of Technology（昆士兰科技大学）；Nvidia AI technology centre（英伟达人工智能技术中心）；Airdoc Research（Airdoc研究院）；Monash University（莫纳什大学）；University of New South Wales（新南威尔士大学）
UC Berkeley（加州大学伯克利分校）；X, The Moonshot Factory（X（登月工厂））；Intrinsic Innovation LLC（Intrinsic创新有限责任公司）；Google Research（谷歌研究院）
In recent years, impressive results have been achieved in robotic manipulation. While many efforts focus on generating collision-free reference signals, few allow safe contact between the robot bodies and the environment. However, in human's daily manipulation, contact between arms and obstacles is prevalent and even necessary. This paper investigates the benefit of allowing safe contact during robotic manipulation and advocates generating and tracking compliance reference signals in both operational and null spaces. In addition, to optimize the collision-allowed trajectories, we present a hyb…
Southern University of Science and Technology（南方科技大学）
Soft grippers are receiving growing attention due to their compliance-based interactive safety and dexterity. Hybrid gripper (soft actuators enhanced by rigid constraints) is a new trend in soft gripper design. With right structural components actuated by soft actuators, they could achieve excellent grasping adaptability and payload, while also being easy to model and control with conventional kinematics. However, existing works were mostly focused on achieving superior payload and perception with simple planar workspaces, resulting in far less dexterity compared with conventional grippers. In…
Plug, Play and Comply: Plugin-Based Compliant Control in ROS 2
College of Information Science and Technology, Eastern Institute of Technology（信息科学与技术学院，东方理工学院）；Zhejiang Key Laboratory of Industrial Intelligence and Digital Twin, Eastern Institute of Technology（浙江省工业智能与数字孪生重点实验室，东方理工学院）
