Collision Detection with Analytical Derivatives of Contact Kinematics
Department of Mechanical and Nuclear Engineering, Khalifa University of Science and Technology（卡利法大学科学与技术学院机械与核工程系）；Khalifa University Center for Autonomous Robotic Systems (KUCARS)（卡利法大学自主机器人系统中心）；The BioRobotics Institute, Scuola Superiore Sant’Anna（圣安娜高等学院生物机器人研究所）；Department of Excellence in Robotics and AI, Scuola Superiore Sant’Anna（圣安娜高等学院机器人与人工智能卓越部门）；LS2N Laboratory, Institut Mines Telecom Atlantique（Atlantique电信学院LS2N实验室）
Differentiable contact kinematics are essential for gradient-based methods in robotics, yet the mapping from robot state to contact distance, location, and normal becomes non-smooth in degenerate configurations of shapes with zero or undefined curvature. We address this inherent limitation by selectively regularizing such geometries into strictly convex implicit representations, restoring uniqueness and smoothness of the contact map. Leveraging this geometric regularization, we develop iDCOL, an implicit differentiable collision detection and contact kinematics framework. iDCOL represents colliding bodies using strictly convex implicit surfaces and computes collision detection and contact kinematics by solving a fixed-size nonlinear system derived from a geometric scaling-based convex optimization formulation. By applying the Implicit Function Theorem to the resulting system residual, we derive analytical derivatives of the contact kinematic quantities. We develop a fast Newton-based solver for iDCOL and provide an open-source C++ implementation of the framework. The robustness of the approach is evaluated through extensive collision simulations and benchmarking, and applicability is demonstrated in gradient-based kinematic path planning and differentiable contact physics, including multi-body rigid collisions and a soft-robot interaction example.
Italian Institute of Technology（意大利理工学院）；University of Genoa（热那亚大学）；University of Manchester（曼彻斯特大学）
Full-body motion estimation of a human through wearable sensing technologies is challenging in the absence of position sensors. This paper contributes to the development of a model-based whole-body kinematics estimation algorithm using wearable distributed inertial and force-torque sensing. This is done by extending the existing dynamical optimization-based Inverse Kinematics (IK) approach for joint state estimation, in cascade, to include a center of pressure-based contact detector and a contact-aided Kalman filter on Lie groups for floating base pose estimation. The proposed method is tested…
University of Michigan（密歇根大学）；Toyota Research Institute（丰田研究院）
State-of-the-art robotic perception systems have achieved sufficiently good performance using Inertial Measurement Units (IMUs), cameras, and nonlinear optimization techniques, that they are now being deployed as technologies. However, many of these methods rely significantly on vision and often fail when visual tracking is lost due to lighting or scarcity of features. This paper presents a state-estimation technique for legged robots that takes into account the robot's kinematic model as well as its contact with the environment. We introduce forward kinematic factors and preintegrated contact…
A Unified Framework for Multi-Contact Path Planning in the Rolling Robot Systems
Geometric Mechanics and Mechatronics in Robotics (gm 2 R) Lab, School of Engineering, Cardiff University（机器人几何力学与机电学实验室，工程学院，卡迪夫大学）；Information Science and Engineering Department, Ritsumeikan University（信息科学与工程系，立命馆大学）
Robust Rigid Body Assembly via Contact-Implicit Optimal Control with Exact Second-Order Derivatives
Autonomous Systems and Control, Siemens AG, Germany（自动化系统与控制，西门子股份有限公司，德国）；Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany（微系统工程系（IMTEK），弗赖堡大学，德国）；Department of Mathematics, University of Freiburg, Germany（数学系，弗赖堡大学，德国）
Distilling Contact Planning for Fast Trajectory Optimization in Robot Air Hockey
Idiap Research Institute（Idiap研究 institute）；École Polytechnique Fédérale de Lausanne（瑞士联邦理工学院）；Intelligent Autonomous Systems, TU Darmstadt（智能自主系统，德累斯顿技术大学）；German Research Center for AI (DFKI)（德国人工智能研究中心）；Centre for Cognitive Science, Hessian.AI（认知科学中心，Hessian.AI）
Legged robots require knowledge of pose and velocity in order to maintain stability and execute walking paths. Current solutions either rely on vision data, which is susceptible to environmental and lighting conditions, or fusion of kinematic and contact data with measurements from an inertial measurement unit (IMU). In this work, we develop a contact-aided invariant extended Kalman filter (InEKF) using the theory of Lie groups and invariant observer design. This filter combines contact-inertial dynamics with forward kinematic corrections to estimate pose and velocity along with all current co…
This paper presents a new kinematic model based on the Darboux frame for motion control and planning. In this work, we show that an underactuated model of a spin-rolling sphere on a plane with five states and three inputs can be transformed into a fully-actuated one by a given Darboux frame transformation. This nonlinear state transformation establishes a geometric model that is different from conventional state-space ones. First, a kinematic model of the Darboux frame at the contact point of the rolling sphere is established. Next, we propose a virtual surface that is trapped between the sphe…
University of Arkansas（阿肯色大学）；Columbia University（哥伦比亚大学）；Vanderbilt University（范德堡大学）
Soft robots offer an alternative approach to manipulate inside the constrained space while maintaining the safe interaction with the external environment. Due to its adaptable compliance characteristic, external contact force can easily deform the robot shapes and lead to undesired robot kinematic and dynamic properties. Accurate contact detection and contact position estimation are of critical importance for soft robot modeling, control, trajectory planning, and eventually affect the success of task completion. In this paper, we focus on the study of 1-DoF soft pneumatic bellow bending actuat…
Georgia Institute of Technology（佐治亚理工学院）；Twentieth Century Fox（二十世纪福克斯公司）；Starfleet Academy（星际舰队学院）；Tyrell Inc.（泰伦公司）
This paper presents a multi-contact motion adaptation framework that enables teleoperation of high degree-of-freedom (DoF) robots, such as quadrupeds and humanoids, for loco-manipulation tasks in multi-contact settings. Our proposed algorithms optimize whole-body configurations and formulate the retargeting of multi-contact motions as sequential quadratic programming, which is robust and stable near the edges of feasibility constraints. Our framework allows real-time operation of the robot and reduces cognitive load for the operator because infeasible commands are automatically adapted into ph…
DexViTac: Collecting Human Visuo-Tactile-Kinematic Demonstrations for Contact-Rich Dexterous Manipulation
State Key Laboratory of Intelligent Manufacturing Equipment and Technology（智能制造装备与技术国家重点实验室）；Huazhong University of Science and Technology（华中科技大学）；Wuhan Huaweike Intelligent Technology Co., Ltd.（武汉华为凯科技有限公司）
University of Toronto Institute for Aerospace Studies（多伦多大学航空航天研究所）；University of Zagreb（萨格勒布大学）
We present a novel approach for mobile manipulator self-calibration using contact information. Our method, based on point cloud registration, is applied to estimate the extrinsic transform between a fixed vision sensor mounted on a mobile base and an end effector. Beyond sensor calibration, we demonstrate that the method can be extended to include manipulator kinematic model parameters, which involves a non-rigid registration process. Our procedure uses on-board sensing exclusively and does not rely on any external measurement devices, fiducial markers, or calibration rigs. Further, it is full…
Design of an In-Pipe Robot with Contact-Angle-Guided Kinematic Decoupling for Crosstalk-Suppressed Locomotion
Robotics and Autonomous Systems Thrust, The Hong Kong University of Science and Technology (Guangzhou)（香港科技大学（广州）机器人与自主系统学域）；Department of Engineering, Shinshu University（信州大学工学部）；College of Information Science and Technology, Beijing University of Chemical Technology（北京化工大学信息科学与技术学院）
Teaching contact-rich tasks from visual demonstrations by constraint extraction
Fraunhofer IPK（弗劳恩霍夫生产设备与设计技术研究所）；Politecnico di Milano（米兰理工大学）；Istituto Dalle Molle di Studi sull’Intelligenza Artificiale (IDSIA)（达莱莫勒人工智能研究所（IDSIA））；Scuola Universitaria Professionale della Svizzera Italiana (SUPSI)（瑞士意大利语区应用科学大学（SUPSI））；Università della Svizzera Italiana (USI)（瑞士意大利语区大学（USI））
Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University in Prague（布拉格捷克理工大学电气工程学院控制论系）；Czech Institute of Informatics, Robotics, and Cybernetics, Czech Technical University in Prague（布拉格捷克理工大学捷克信息学、机器人学与控制论研究所）
We present a robot kinematic calibration method that combines complementary calibration approaches: self-contact, planar constraints, and self-observation. We analyze the estimation of the end effector parameters, joint offsets of the manipulators, and calibration of the complete kinematic chain (DH parameters). The results are compared with ground truth measurements provided by a laser tracker. Our main findings are: (1) When applying the complementary calibration approaches in isolation, the self-contact approach yields the best and most stable results. (2) All combinations of more than one …
The Kinetics Observer: A Tightly Coupled Estimator for Legged Robots
CNRS-AIST JRL (Joint Robotics Laboratory)（法国国家科学研究中心-日本产业技术综合研究所联合机器人实验室）；National Institute of Advanced Industrial Science and Technology (AIST)（日本产业技术综合研究所）；Université Paris-Saclay（巴黎萨克雷大学）；Laboratoire d’Ingénierie des Systèmes de Versailles（凡尔赛系统工程实验室）；CNRS-University of Montpellier（法国国家科学研究中心-蒙彼利埃大学）
Ankle push-off largely contributes to limb energy generation in human walking, leading to smoother and more efficient locomotion. Providing this net positive work to an amputee requires an active prosthesis, but has the potential to enable more natural assisted locomotion. To this end, this paper uses multi-contact models of locomotion together with force-based nonlinear optimization-based controllers to achieve human-like kinematic behavior, including ankle push-off, on a powered transfemoral prosthesis for 2 subjects. In particular, we leverage model-based control approaches for dynamic bipe…
The University of Texas at Austin（德克萨斯大学奥斯汀分校）；University of Notre Dame（圣母大学）
Optimization-based robot control strategies often rely on first-order dynamics approximation methods, as in iLQR. Using second-order approximations of the dynamics is expensive due to the costly second-order partial derivatives of the dynamics with respect to the state and control. Current approaches for calculating these derivatives typically use automatic differentiation (AD) and chain-rule accumulation or finite-difference. In this paper, for the first time, we present analytical expressions for the second-order partial derivatives of inverse dynamics for open-chain rigid-body systems with …
Georgia Institute of Technology（佐治亚理工学院）；Florida Institute for Human & Machine Cognition（佛罗里达人机认知研究所）；University of West Florida（西佛罗里达大学）
Legged robot locomotion is a challenging task due to a myriad of sub-problems, such as the hybrid dynamics of foot contact and the effects of the desired gait on the terrain. Accurate and efficient state estimation of the floating base and the feet joints can help alleviate much of these issues by providing feedback information to robot controllers. Current state estimation methods are highly reliant on a conjunction of visual and inertial measurements to provide real-time estimates, thus being handicapped in perceptually poor environments. In this work, we show that by leveraging the kinemati…
Based on the convex force-motion polynomial model for quasi-static sliding, we derive the kinematic contact model to determine the contact modes and instantaneous object motion on a supporting surface given a position controlled manipulator. The inherently stochastic object-to-surface friction distribution is modelled by sampling physically consistent parameters from appropriate distributions, with only one parameter to control the amount of noise. Thanks to the high fidelity and smoothness of convex polynomial models, the mechanics of patch contact is captured while being computationally effi…
Georgia Institute of Technology（佐治亚理工学院）；NVIDIA（英伟达）；University of Utah（犹他大学）；University of Washington（华盛顿大学）
To perform complex tasks, robots must be able to interact with and manipulate their surroundings. One of the key challenges in accomplishing this is robust state estimation during physical interactions, where the state involves not only the robot and the object being manipulated, but also the state of the contact itself. In this work, within the context of planar pushing, we extend previous inference-based approaches to state estimation in several ways. We estimate the robot, object, and the contact state on multiple manipulation platforms configured with a vision-based articulated model track…
Osaka University（大阪大学）；National Institute of Advanced Industrial Science and Technology（产业技术综合研究所）
This paper uses a mobile manipulator with a collaborative robotic arm to manipulate objects beyond the robot's maximum payload. It proposes a single-shot probabilistic roadmap-based method to plan and optimize manipulation motion with environment support. The method uses an expanded object mesh model to examine contact and randomly explores object motion while keeping contact and securing affordable grasping force. It generates robotic motion trajectories after obtaining object motion using an optimization-based algorithm. With the proposed method's help, we can plan contact-rich manipulation …
