检索结果-内蒙古大学图书馆

2001 IEEE computer Society Conference on computer vision and Pattern Recognition

作者： Argyros, Antonis A. Bekris, Kostas E. Orphanoudakis, Stelios C. Computer Vision and Robotics Lab. Institute of Computer Science Found. for Res./Technology - Hellas Heraklion Crete Greece

In robotics, homing can be defined as that behavior which enables a robot to return to its initial (home) position, after traveling a certain distance along an arbitrary path. Odometry has traditionally been used for the implementation of such a behavior, but it has been shown to be an unreliable source of information. In this work, a novel method for visual homing is proposed, based on a panoramic camera. As the robot departs from its initial position, it tracks characteristic features of the environment (corners). As soon as homing is activated, the robot selects intermediate target positions on the original path. These intermediate positions (IPs) are then visited sequentially, until the home position is reached. For the robot to move between two consecutive IPs, it is only required to establish correspondence among at least three corners. This correspondence is obtained through a feature tracking mechanism. The proposed homing scheme is based on the extraction of very low-level sensory information, namely the bearing angles of corners, and has been implemented on a robotic platform. Experimental results show that the proposed scheme achieves homing with a remarkable accuracy, which is not affected by the distance travelled by the robot.

关键词： robotics

来源：评论

学校读者我要写书评

暂无评论

Artificial landmark tracking based on the color histogram

Artificial landmark tracking based on the color histogram

引用

2001 IEEE/RSJ International Conference on Intelligent Robots and Systems

作者： Yoon, Kuk-Jin Kweon, In-So Robotics and Computer Vision Lab. Dept. of Elec. Eng. and Comp. Sci. KAIST Taejon Korea Republic of

For the fast and accurate self-localization of mobile robots, landmarks can be used very efficiently in the complex workspace. In this paper, we propose a simple color landmark model for self-localization and a fast landmark detection and tracking algorithm based on the proposed landmark model. We develop a color landmark with a symmetric and repetitive structure, which shows invariant color histogram characteristics under some geometric distortions. Detection and tracking of the model are accomplished by a factored sampling technique in which color similarity is estimated by the color histogram intersection. We also use the color similarity to update the color histogram model of the landmark model for robust tracking under illumination change. We demonstrate the feasibility of the proposed technique through experiments in cluttered indoor environments.

关键词： Mobile robots

来源：评论

学校读者我要写书评

暂无评论

Software mode changes for continuous motion tracking 1st

Software mode changes for continuous motion tracking

引用

1st International Workshop on Self-Adaptive Software, IWSAS 2000

作者： Karuppiah, Deepak Deegan, Patrick Araujo, Elizeth Yang, Yunlei Holness, Gary Zhu, Zhigang Lerner, Barbara Grupen, Roderic Riseman, Edward Dept. of Computer Science Computer Vision Research Laboratory University of Massachusetts AmherstMA01003 United States Dept. of Computer Science Laboratory for Perceptual Robotics University of Massachusetts AmherstMA01003 United States Dept. of Computer Science Lab. for Advanced Software Eng. Research University of Massachusetts AmherstMA01003 United States

ISBN: (纸本)3540416552

Robot control in nonlinear and nonstationary run-time environments presents challenges to traditional software methodologies. In particular, robot systems in "open" domains can only be modeled probabilistically and must rely on run-time feedback to detect whether hardware/software configurations are adequate. Modifications must be effected while guaranteeing critical performance properties. Moreover, in multi-robot systems, there are typically many ways in which to compensate for inadequate performance. The computational complexity of high dimensional sensorimotor systems prohibits the use of many traditional centralized methodologies. We present an application in which a redundant sensor array, distributed spatially over an office-like environment can be used to track and localize a human being while reacting at run-time to various kinds of faults, including: hardware failure, inadequate sensor geometries, occlusion, and bandwidth limitations. Responding at run-time requires a combination of knowledge regarding the physical sensorimotor device, its use in coordinated sensing operations, and high- level process descriptions. We present a distributed control architecture in which run-time behavior is both preanalyzed and recovered empirically to inform local scheduling agents that commit resources autonomously subject to process control specifications. Preliminary examples of system performance are presented from the UMass Self-Adaptive Software (SAS) platform. © Springer-Verlag Berlin Heidelberg 2001.

关键词： Process control

来源：评论

学校读者我要写书评

暂无评论

Lateral control of an aerial unmanned robot using visual servoing techniques

Lateral control of an aerial unmanned robot using visual ser...

引用

International Workshop on Robot Motion and Control (RoMoCo)

作者： G.F. Silveira J. Reginaldo H. Carvalho M.K. Madrid S.S. Bueno P. Rives Robotics and Computer Vision Laboratory/ITI Campinas SP Brazil the State University of Campinas (UNICAMP) Robotics Lab Campinas SP Brazil Patrick Rives is with INRIA Sophia-Antipolis France

This work addresses the issue of the lateral control of an outdoor robotic airship while following a predefined path using visual servoing techniques. The vision-based control application is based on an interaction matrix related to line features extracted from an on-board camera as feedback signals. An output LQR controller for the visual servo control is designed using the lateral dynamic model of the airship. The proposed approach is validated using a realistic simulator of the AS-800 unmanned airship.

关键词： Visual servoing Aerodynamics Vehicle dynamics Robot vision systems Automatic control Servosystems Robot sensing systems robotics and automation Unmanned aerial vehicles Cameras

来源：评论

学校读者我要写书评

暂无评论

Edge-based algorithm for discontinuity adaptive color image smoothing

引用

Pattern Recognition 2001年第2期34卷 333-342页

作者： Kang, Dong Joong Kweon, In So Signal Processing Lab. Samsung Adv. Institute of Technology P.O. Box 111 Suwon 440-600 Korea Republic of Robotics and Computer Vision Lab. Department of Electrical Engineering Korea Adv. Inst. Sci. and Technol. 207-43 Cheong. Dongdaemoon-Gu Seoul United States Pusan National University Pusan Korea Republic of KAIST Seoul Korea Republic of Seoul National University Seoul Korea Republic of Carnegie Mellon University Pittsburgh PA United States

We present a new scheme to increase the performance of edge-preserving image smoothing algorithm from the parameter tuning of a Markov random field (MRF) function. This method is based on an automatic control of the image-smoothing strength in the MRF function in which the parameter control of the function depends on edge magnitude resulted from discontinuities of image intensity. Without any binary decision for the edge magnitude, direct use of full edge magnitude could improve the performance of discontinuity-preserving image smoothing technique.

关键词： Image enhancement

来源：评论

学校读者我要写书评

暂无评论

Combining central and peripheral vision for reactive robot navigation

Combining central and peripheral vision for reactive robot n...

引用

Proceedings of the 1999 IEEE computer Society Conference on computer vision and Pattern Recognition (CVPR'99)

作者： Argyros, Antonis A. Bergholm, Fredrik Computer Vision and Robotics Lab Crete Greece

ISBN: (纸本)769501494

In this paper, we present a new method for vision-based, reactive robot navigation that enables a robot to move in the middle of the free space by exploiting both central and peripheral vision. The robot employs a forward-looking camera for central vision and two side-looking cameras for sensing the periphery of its visual field. The developed method combines the information acquired by this trinocular vision system and produces low-level motor commands that keep the robot in the middle of the free space. The approach follows the purposive vision paradigm in the sense that vision is not studied in isolation but in the context of the behaviors that the system is engaged as well as the environment and the robot's motor capabilities. It is demonstrated that by taking into account these issues, vision processing can be drastically simplified, still giving rise to quite complex behaviors. The proposed method does not make strict assumptions about the environment, requires very low level information to be extracted from the images, produces a robust robot behavior and is computationally efficient. Results obtained by both simulations and from a prototype on-line implementation demonstrate the effectiveness of the method.

关键词： computer vision

来源：评论

学校读者我要写书评

暂无评论

Integrated framework for developing search and discrimination metrics

Integrated framework for developing search and discriminatio...

引用

Targets and Backgrounds: Characterization and Representation III

作者： Copeland, Anthony C. Trivedi, Mohan M. Comp. Vision and Robotics Res. Lab. Electrical and Computer Eng. Dept. University of California San Diego San Diego CA 92093-0407 United States

This paper presents an experimental framework for evaluating target signature metrics as models of human visual search and discrimination. This framework is based on a prototype eye tracking testbed, the Integrated Testbed for Eye Movement Studies (ITEMS). ITEMS determines an observer's visual fixation point while he studies a displayed image scene, by processing video of the observer's eye. The utility of this framework is illustrated with an experiment using gray-scale images of outdoor scenes that contain randomly placed targets. Each target is a square region of a specific size containing pixel values from another image of an outdoor scene. The real-world analogy of this experiment is that of a military observer looking upon the sensed image of a static scene to find camouflaged enemy targets that are reported to be in the area. ITEMS provides the data necessary to compute various statistics for each target to describe how easily the observers located it, including the likelihood the target was fixated or identified and the time required to do so. The computed values of several target signature metrics are compared to these statistics, and a second-order metric based on a model of image texture was found to be the most highly correlated.

关键词： Automatic target recognition

来源：评论

学校读者我要写书评

暂无评论

Vector fields for task-level distributed manipulation: experiments with organic micro actuator arrays

Vector fields for task-level distributed manipulation: exper...

引用

IEEE International Conference on robotics and Automation (ICRA)

作者： K.-F. Bohringer J.W. Suh B.R. Donald G.T.A. Kovacs Robotics & Vision Lab Department of Computer Science Cornell University Ithaca NY USA Transducers Lab Department of Electrical Engineering University of Stanford Stanford CA USA Robotics Lab Department of Computer Science University of Stanford Stanford CA USA

Distributed manipulation experiments were performed using a massively-parallel, microfabricated actuator array. An organic ciliary array of thin-film polyimide bimorph microactuators exploiting combined thermal and electrostatic control was employed to implement task-level, sensorless manipulation strategies for macroscopic objects. The tasks of parts-translation, -rotation, -orientation, and -centering were demonstrated using small integrated circuit (IC) dice. Strategies were programmed in a fine-grained SIMD (single instruction, multiple data) fashion by specifying planar force vector fields. When a part is placed on the array, the programmed vector field induces a force and moment upon it. The part's equilibrium states may be predicted and cascaded (using a sequence of fields) to bring the part to a desired final state. Vector fields with and without potential were tested in experiments, and the behavior of parts in the fields was compared with the theory of programmable vector fields. These fields were implemented by actuating the organic cilia in a cyclic, gait-like fashion. Motion in non-principal (e.g. diagonal) directions was effected by a pairwise coupling of the cilia to implement virtual cilia. These experiments suggest that MEMS actuator arrays are useful for parts-orientation, -posing, -transfer, -singulation, and -sorting.

关键词： Actuators Sensor arrays Thin film circuits Thin film sensors Polyimides Microactuators Electrostatics Sensorless control Force sensors Testing

来源：评论

学校读者我要写书评

暂无评论

The area bisectors of a polygon and force equilibria in programmable vector fields 97

The area bisectors of a polygon and force equilibria in prog...

引用

Proceedings of the thirteenth annual symposium on Computational geometry

作者： Karl-Friedrich Böhringer Bruce Randall Donald Dan Halperin ALPHA Lab Dept. of Ind. Eng. and Op. Research Univ. of CA Berkeley and Robotics & Vision Lab Dept. of Comp. Sc. Cornell Univ. Robotics & Vision Laboratory Department of Computer Science Cornell University Dept. of Comp. Sc. Tel Aviv Univ. Tel Aviv 69978 Israel

来源：评论

学校读者我要写书评

暂无评论

What programmable vector fields can (and cannot) do: force field algorithms for MEMS and vibratory plate parts feeders

What programmable vector fields can (and cannot) do: force f...

引用

IEEE International Conference on robotics and Automation (ICRA)

作者： K.-F. Bohringer B.R. Donald N.C. MacDonald Robotics & Vision Lab. Cornell Univ. Ithaca NY USA Robotics & Vision Laboratory Department of Computer Science Cornell University Ithaca NY USA School of Electrical Engineering and Cornell Nanofabrication Facility Cornell University Ithaca NY USA

Programmable vector fields can be used to control a variety of flexible planar parts feeders. When a part is placed on our devices, the programmed vector field induces a force and moment upon it. Over time, the part may come to rest in a dynamic equilibrium state. We demonstrate lower bounds on what the devices cannot do, and results on a classification of control strategies. We suggest sufficient conditions for programmable fields to induce well-behaved equilibria on every part placed on our devices. We define composition operators to build complex strategies from simple ones, and show the resulting fields are also well-behaved. We discuss whether fields outside this class can be useful and free of pathology. Using these tools, we describe new manipulation algorithms, and improve existing planning algorithms by a quadratic factor, and the plan-length by a linear factor. We relax earlier dynamic and mechanical assumptions to obtain more robust and flexible strategies. Finally, we consider parts feeders that can only implement a very limited "vocabulary" of vector fields. We discuss the trade-off between mechanical complexity and planning complexity.

关键词： Micromechanical devices Automatic control Force control Feeds Assembly Robot vision systems laboratories computer science Nanofabrication Uniform resource locators

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：