检索结果-内蒙古大学图书馆

AIAA Guidance, Navigation, and control Conference, 2016

作者： Perez, Andres E. Moncayo, Hever Prazenica, Richard J. Zacny, Kris Mueller, Robert P. Ebert, Tom Dupuis, Michael Flight Dynamics and Control Research Laboratory Embry-Riddle Aeronautical University Daytona BeachFL32114 United States Aerospace Engineering Department Embry-Riddle Aeronautical University Daytona BeachFL32114 United States Exploration Technology Group Honneybee Robotics Company CA United States Exploration Research and Technology Programs Science and Technology Projects Division NASA Kennedy Space Center FL United States Autonomous Flight Systems Lead Testing and Design Branch NASA Kennedy Space Center FL United States Robotics and Autonomous Systems Testing and Design Branch NASA Kennedy Space Center FL United States

ISBN: (数字)9781624103896

ISBN: (纸本)9781624103896

In situ Resource Utilization (ISRU) facilitates planetary exploration by drawing needed resources, such as water, from the local environment. However, the extreme nature of these environments require the development of advanced unmanned space systems integrated with sample-capture devices to achieve the ultimate goal of prospecting these resources. This paper presents the design, development and Hardware-in-the-Loop (HIL) simulation testing of guidance and tracking control laws for an autonomous small marsupial free-flyer prospector system. The control laws are based on an extended non-linear dynamic inversion (NLDI) approach and its implementation is illustrated through HIL simulation using a mathematical model of an autonomous vehicle research platform developed by NASA Kennedy Space Center. This vehicle has been designed to support the development, testing and validation of algorithms for safe, reliable, and scalable control space missions with minimal need for human intervention in complex, unstructured environments. The main objective of the control laws is to minimize 3-axis distances with respect to a desired trajectory and maintain stability and adequate performance in the presence of uncertainties. The performance of the control laws is evaluated during autonomous flight in terms of trajectory tracking errors, real-time execution on board the flight computer, and control activity at nominal and dynamically-changing conditions. The results show that for all mission cases investigated the control laws approach has desirable capabilities and is reliable for in-flight testing operation as a next step towards the validation and verification of this configuration. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Hardware-in-the-loop simulation

来源：评论

学校读者我要写书评

暂无评论

Task specific cooperative grasp planning for decentralized multi-robot systems

Task specific cooperative grasp planning for decentralized m...

引用

IEEE International Conference on robotics and Automation (ICRA)

作者： Rajkumar Muthusamy Charalampos P. Bechlioulis Kostas J. Kyriakopoulos Ville Kyrki The authors are with the Intelligent Robotics Group Aalto University Finland Control Systems Laboratory National Technical University of Athens Zografou Greece

ISBN: (纸本)9781479969241

Grasp planning in multi-robot systems is usually studied in a centralized setting with all robots sharing common knowledge about the overall system. Relaxing this assumption would allow multiple mobile manipulators to cooperate even without strict and precise coordination. Moreover, most typical tasks for cooperative settings, such as transporting heavy objects, require certain forces/torques to be exerted along/around particular directions, for instance, compensating for the weight of the transported object. In this paper, we propose task specific multi-robot grasp planning strategies that allow decentralized planning. Each agent plans its own actions without precise information about the other's plans. The approach is based on analysing a task specific grasp quality metric in a probabilistic context, compensating thus for the incomplete knowledge. Results from simulation experiments demonstrate that task independent planning is clearly inferior when task characteristics are known and thus task specific quality measures should be used. Furthermore, the proposed decentralized planning approaches clearly outperform the baseline and show close to globally optimal performance.

关键词： Planning Robot kinematics Grasping Measurement Force Multi-robot systems

来源：评论

学校读者我要写书评

暂无评论

control system for neuro-prostheses integrating induced and volitional effort 9

Control system for neuro-prostheses integrating induced and ...

引用

9th IFAC Symposium on Biological and Medical systems, BMS 2015

作者： Ambrosini, E. Schauer, T. Klauer, C. Pedrocchi, A. Ferrigno, G. Ferrante, S. NeuroEngineering and Medical Robotics Laboratory NearLab Department of Electronics Information and Bioengineering Politecnico di Milano Italy Control Systems Group Technische Universität Berlin Germany Physical Medicine and Rehabilitation Unit Scientific Institute of Lissone Institute of Care and Research Salvatore Maugeri Foundation IRCCS Lissone Italy

To increase the rehabilitation outcomes of stroke patients with weak residual muscle activity, a novel control strategy for Functional Electrical Stimulation (FES) was designed and tested during a tracking task. The system includes an electromyography (EMG)-based feedback controller and a trial-to-trial adaptation of the FES support. The first modulates the stimulation intensity to achieve a desired amount of FES-evoked muscle activity corresponding to a desired FES-induced angular support trajectory. The second iteratively updates this trajectory in order to minimize the error between the target displayed to the patient and the measured angle trajectory. This support adaptation only takes place in case the subject actively contributes to the movement. If the estimated volitional effort is too low, FES support is quickly withdrawn to remind the subject to actively contribute to the tracking task. The EMG signal of the stimulated muscle is used to estimate both the FES-induced and the volitional muscle activity. The feasibility of the proposed control scheme was experimentally investigated in one healthy subject by stimulating the medial deltoid muscle to support shoulder abduction. First, the controller was tested simulating different volitional contributions of a potential patient. The control system adjusted the amount of FES-support as expected. Then, the compensation of muscle fatigue by the feedback controller was demonstrated by repeatedly applying the same desired FES-induced angular trajectories, while the subject was asked to be relaxed. As a result, the control system was able to provide the desired support for about 7 minutes until the stimulation intensity saturated. © 2015, IFAC (International Federation of Automatic control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Electromyography

来源：评论

学校读者我要写书评

暂无评论

Real time object tracking via a mixture model

Real time object tracking via a mixture model

引用

IEEE International Workshop on Robot and Human Communication (ROMAN)

作者： Dongxu Gao Zhaojie Ju Jiangtao Cao Honghai Liu Intelligent Systems and Biomedical Robotics group School of Computing’ University of Portsmouth Portsmouth England Department of Information and Control Engineering Liaoning Shihua University Fushun Liaoning China

Object tracking has been applied in many fields such as intelligent surveillance and computer vision. Although much progress has been made, there are still many puzzles which pose a huge challenge to object tracking. Currently, the problems are mainly caused by appearance model as well as real-time performance. A novel method was been proposed in this paper to handle both of these problems. Locally dense contexts feature and image information (i.e. the relationship between the object and its surrounding regions) are combined in a Bayes framework. Then the tracking problem can be seen as a prediction question which need to compute the posterior probability. Both scale variations and temple updating are considered in the proposed algorithm to assure the effectiveness. To make the algorithm runs in a real time system, a Fourier Transform (FT) is used when solving the Bayes equation. Therefore, the MMOT (Mixture model for object tracking) runs in real-time and performs better than state-of-the-art algorithms on some challenging image sequences in terms of accuracy, quickness and robustness.

关键词： Computational modeling Image color analysis Hidden Markov models Computer vision Object tracking Pattern recognition Real-time systems

来源：评论

学校读者我要写书评

暂无评论

Modeling, Identification and Joint Impedance control of the Atlas Arms

Modeling, Identification and Joint Impedance Control of the ...

引用

IEEE-RAS International Conference on Humanoid Robots

作者： Moritz Schappler Jonathan Vorndamme Alexander Todtheide David C. Conner Oskar von Stryk Sami Haddadin Institute of Automatic Control at Leibniz Universitat Hanover TORC Robotics Simulation Systems Optimization and Robotics Group at TU Darmstadt

ISBN: (纸本)9781479968862

Compliant manipulation has become central to robots that are sought to safely act in and interact with unstructured as well as only partially known environments. In this paper we equip the hydraulically actuated, usually position controlled arms of the Atlas robot with model-based joint impedance control, including suitable damping design, and experimentally verify the proposed algorithm. Our approach, which originates from the advances in soft-robotics control, relies on high-performance low-level joint torque control. This makes it independent from the actual technology being hydraulic or electromechanical. This paper describes the approach to accurately model the dynamics, and design the optimal excitation trajectory for system identification to enable the specification of model-based feed-forward controls. In conclusion, the implemented controller enables the robot arm to execute significantly smoother motions, be compliant against external forces, and have similar tracking performance as compared to the existing position control scheme. Finally, unknown modeling inaccuracies and contact forces are accurately estimated by a suitable disturbance observer, which could be used in the future to further enhance our controller's performance.

关键词： Robot Arm spiral arm Atlas atlas Atlas Saturn satellites robotic arm disturbance observer Arms CONTACT FORCE Joints Joints Position control Standing Orders

来源：评论

学校读者我要写书评

暂无评论

control system for neuro-prostheses integrating induced and volitional effort ∗

引用

IFAC-PapersOnLine 2015年第20期48卷 327-332页

作者： E. Ambrosini T. Schauer C. Klauer A. Pedrocchi G. Ferrigno S. Ferrante NeuroEngineering And Medical Robotics Laboratory NearLab Department of Electronics Information and Bioengineering Politecnico di Milano Italy Control Systems Group Technische Universität Berlin Germany Physical Medicine and Rehabilitation Unit Scientific Institute of Lissone Institute of Care and Research Salvatore Maugeri Foundation IRCCS Lissone Italy

关键词： Signal processing Medical systems Biomedical control Rehabilitation Functional Electrical Stimulation Electromyography

来源：评论

学校读者我要写书评

暂无评论

A robust nonlinear controller for nontrivial quadrotor maneuvers: Approach and verification

A robust nonlinear controller for nontrivial quadrotor maneu...

引用

IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Yuyi Liu J. M. Montenbruck P. Stegagno F. Allgower A. Zell Department of Computer Science University of Tubingen Tubingen Germany Autonomous Robotics and Human-Machine Systems group Max Planck Institute for Biological Cybernetics Tubingen Germany Institute for Systems Theory and Automatic Control University of Stuttgart Stuttgart Germany Eberhard Karls Universitat Tubingen Tubingen Baden-WÃ¼rttemberg DE

This paper presents a nonlinear control approach for quadrotor Micro Aerial Vehicles (MAVs), which combines a backstepping-like regulator based on the solution of a certain class of global output regulation problems for the rigid body equations on SO(3), a robust controller for the system with bounded disturbances, as well as a trajectory generator using a model predictive control method. The proposed algorithm is endowed with strong convergence properties so that it allows the quadrotor MAVs to reach almost all the desired attitudes. The control approach is implemented on a high-payload-capable quadcopter with unstructured dynamics and unknown disturbances. The performance of our algorithm is demonstrated through a series of experimental evaluations and comparisons with another control method on normal and aggressive trajectory tracking tasks.

关键词： Attitude control Trajectory Robustness Heuristic algorithms Mathematical model Tracking Aerodynamics

来源：评论

学校读者我要写书评

暂无评论

[email protected] : Analysis and results of evolving competitions for domestic and service robots

引用

Artificial Intelligence 2015年 229卷 258-281页

作者： Luca Iocchi Dirk Holz Javier Ruiz-del-Solar Komei Sugiura Tijn van der Zant Department of Computer Control and Management Engineering Sapienza University of Rome Italy Autonomous Intelligent Systems Group University of Bonn Germany Department of Electrical Engineering & Advanced Mining Technology Center Universidad de Chile Chile Information Services Platform Laboratory National Institute of Information and Communications Technology Japan Cognitive Robotics Laboratory University of Groningen The Netherlands

Scientific competitions are becoming more common in many research areas of artificial intelligence and robotics, since they provide a shared testbed for comparing different solutions and enable the exchange of research results. Moreover, they are interesting for general audiences and industries. Currently, many major research areas in artificial intelligence and robotics are organizing multiple-year competitions that are typically associated with scientific conferences. One important aspect of such competitions is that they are organized for many years. This introduces a temporal evolution that is interesting to analyze. However, the problem of evaluating a competition over many years remains unaddressed. We believe that this issue is critical to properly fuel changes over the years and measure the results of these decisions. Therefore, this article focuses on the analysis and the results of evolving competitions. In this article, we present the [email protected] competition, which is the largest worldwide competition for domestic service robots, and evaluate its progress over the past seven years. We show how the definition of a proper scoring system allows for desired functionalities to be related to tasks and how the resulting analysis fuels subsequent changes to achieve general and robust solutions implemented by the teams. Our results show not only the steadily increasing complexity of the tasks that [email protected] robots can solve but also the increased performance for all of the functionalities addressed in the competition. We believe that the methodology used in [email protected] for evaluating competition advances and for stimulating changes can be applied and extended to other robotic competitions as well as to multi-year research projects involving Artificial Intelligence and robotics.

关键词： Robotic competitions Artificial intelligence and robotics Benchmarking

来源：评论

学校读者我要写书评

暂无评论

An Algorithm for Real-time Object Tracking in Complex Environment

An Algorithm for Real-time Object Tracking in Complex Enviro...

引用

International Joint Conference on Neural Networks

作者： Dongxu Gao Jiangtao Cao Zhaojie Ju Department of Information and Control Engineering Liaoning Shihua University Intelligent Systems and Biomedical Robotics group School of Creative Technologies University of Portsmouth

ISBN: (纸本)9781479914821

The current sparse representation tracking algorithm is not suitable for the objects that illumination changes, scale changes, the object color is similar with the surrounding region, and occlusion etc, what's more, it is hard to realize real-time tracking for solving an l1 norm related minimization problems. An optimal algorithm is introduced by exploiting an accelerated proximal gradient approach which contains some improvements of particle filter function, sparse representation alterative weights and coefficient. These improvements not only reduce the influences of appearance change but also make the tracker runs in real time. Both qualitative and quantitative evaluations demonstrate that the proposed tracking algorithm has favorably better performance than several state-of-the-art trackers using challenging benchmark image sequences, and significantly reduces the computing cost.

关键词： Target tracking Principal component analysis Minimization Lighting Mathematical model Real-time systems

来源：评论

学校读者我要写书评

暂无评论

Identifying the best machine learning algorithms for brain tumor segmentation, progression assessment, and overall survival prediction in the BRATS challenge

arXiv

引用

arXiv 2018年

作者： Bakas, Spyridon Reyes, Mauricio Jakab, Andras Bauer, Stefan Rempfler, Markus Crimi, Alessandro Shinohara, Russell Takeshi Berger, Christoph Ha, Sung Min Rozycki, Martin Prastawa, Marcel Alberts, Esther Lipkova, Jana Freymann, John Kirby, Justin Bilello, Michel Fathallah-Shaykh, Hassan M. Wiest, Roland Kirschke, Jan Wiestler, Benedikt Colen, Rivka Kotrotsou, Aikaterini Lamontagne, Pamela Marcus, Daniel Milchenko, Mikhail Nazeri, Arash Weber, Marc-Andr Mahajan, Abhishek Baid, Ujjwal Gerstner, Elizabeth Kwon, Dongjin Acharya, Gagan Agarwal, Manu Alam, Mahbubul Albiol, Alberto Albiol, Antonio Albiol, Francisco J. Alex, Varghese Allinson, Nigel Amorim, Pedro H.A. Amrutkar, Abhijit Anand, Ganesh Andermatt, Simon Arbel, Tal Arbelaez, Pablo Avery, Aaron Azmat, Muneeza Pranjal, B. Bai, Wenjia Banerjee, Subhashis Barth, Bill Batchelder, Thomas Batmanghelich, Kayhan Battistella, Enzo Beers, Andrew Belyaev, Mikhail Bendszus, Martin Benson, Eze Bernal, Jose Bharath, Halandur Nagaraja Biros, George Bisdas, Sotirios Brown, James Cabezas, Mariano Cao, Shilei Cardoso, Jorge M. Carver, Eric N. Casamitjana, Adri Castillo, Laura Silvana Cat, Marcel Cattin, Philippe Cérigues, Albert Chagas, Vinicius S. Chandra, Siddhartha Chang, Yi-Ju Chang, Shiyu Chang, Ken Chazalon, Joseph Chen, Shengcong Chen, Wei Chen, Jefferson W. Chen, Zhaolin Cheng, Kun Choudhury, Ahana Roy Chylla, Roger Clrigues, Albert Colleman, Steven Colmeiro, Ramiro German Rodriguez Combalia, Marc Costa, Anthony Cui, Xiaomeng Dai, Zhenzhen Dai, Lutao Daza, Laura Alexandra Deutsch, Eric Ding, Changxing Dong, Chao Dong, Shidu Dudzik, Wojciech Eaton-Rosen, Zach Egan, Gary Escudero, Guilherme Estienne, Tho Everson, Richard Fabrizio, Jonathan Fan, Yong Fang, Longwei Feng, Xue Ferrante, Enzo Fidon, Lucas Fischer, Martin French, Andrew P. Fridman, Naomi Fu, Huan Fuentes, David Gao, Yaozong Gates, Evan Gering, David Gholami, Amir Gierke, Willi Glocker, Ben Gong, Mingming Gonzlez-Vill, Sandra Grosges, T. Guan, Yuanfang Guo, Sheng Gupta, Sudeep Han, Woo-Sup Han, Il Song Harmuth, Ko Center for Biomedical Image Computing and Analytics University of Pennsylvania PhiladelphiaPA United States Department of Radiology Perelman School of Medicine University of Pennsylvania PhiladelphiaPA United States Department of Pathology and Laboratory Medicine Perelman School of Medicine University of Pennsylvania PhiladelphiaPA United States Institute for Surgical Technology and Biomechanics University of Bern Bern Switzerland Center for MR-Research University Children's Hospital Zurich Zurich Switzerland Support Centre for Advanced Neuroimaging Inselspital Institute for Diagnostic and Interventional Neuroradiology Bern University Hospital Bern Switzerland University Hospital of Zurich Zurich Switzerland Center for Clinical Epidemiology and Biostatistics University of Pennsylvania Philadelphia United States Image-Based Biomedical Modeling Group Technical University of Munich Munich Germany Icahn School of Medicine Mount Sinai Health System New YorkNY United States Leidos Biomedical Research Inc. Frederick National Laboratory for Cancer Research FrederickMD21701 United States Cancer Imaging Program National Cancer Institute National Institutes of Health BethesdaMD20814 United States Department of Neurology University of Alabama at Birmingham BirminghamAL United States Department of Diagnostic Radiology University of Texas MD Anderson Cancer Center HoustonTX United States Department of Psychology Washington University St. LouisMO United States Neuroimaging Informatics and Analysis Center Washington University St. LouisMO United States Department of Radiology Washington University St. LouisMO United States Institute of Diagnostic and Interventional Radiology Pediatric Radiology and Neuroradiology University Medical Center Rostock Ernst-Heydemann-Str. 6 Rostock18057 Germany Tata Memorial Centre Homi Bhabha National Institute Mumbai India Shri Guru Gobind Singhji Institute of Engineering and Technology Nanded India NVIDIA Santa Clara

Gliomas are the most common primary brain malignancies, with different degrees of aggressiveness, variable prognosis and various heterogeneous histologic sub-regions, i.e., peritumoral edematous/invaded tissue, necrotic core, active and non-enhancing core. This intrinsic heterogeneity is also portrayed in their radio-phenotype, as their sub-regions are depicted by varying intensity profiles disseminated across multi-parametric magnetic resonance imaging (mpMRI) scans, reflecting varying biological properties. Their heterogeneous shape, extent, and location are some of the factors that make these tumors difficult to resect, and in some cases inoperable. The amount of resected tumor is a factor also considered in longitudinal scans, when evaluating the apparent tumor for potential diagnosis of progression. Furthermore, there is mounting evidence that accurate segmentation of the various tumor sub-regions can offer the basis for quantitative image analysis towards prediction of patient overall survival. This study assesses the state-of-the-art machine learning (ML) methods used for brain tumor image analysis in mpMRI scans, during the last seven instances of the International Brain Tumor Segmentation (BraTS) challenge, i.e., 2012-2018. Specifically, we focus on i) evaluating segmentations of the various glioma sub-regions in pre-operative mpMRI scans, ii) assessing potential tumor progression by virtue of longitudinal growth of tumor sub-regions, beyond use of the RECIST/RANO criteria, and iii) predicting the overall survival from pre-operative mpMRI scans of patients that underwent gross total resection. Finally, we investigate the challenge of identifying the best ML algorithms for each of these tasks, considering that apart from being diverse on each instance of the challenge, the multi-institutional mpMRI BraTS dataset has also been a continuously evolving/growing dataset. Copyright © 2018, The Authors. All rights reserved.

关键词： Tumors

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：