In this paper a sequence of algorithms for image feature point detection and tracking as well as Euclidian reconstruction of rigid three-dimensional objects from point correspondences is presented. For fully automatic...
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ISBN:
(纸本)0819434302
In this paper a sequence of algorithms for image feature point detection and tracking as well as Euclidian reconstruction of rigid three-dimensional objects from point correspondences is presented. For fully automatic point feature detection, grayvalue images are processed. High-curvature points on contours, i.e. contour elements with locally maximal curvature, are tracked using a normalized correlation algorithm. High-curvature points that could be tracked in a sequence of more than three images are used as point features that are eligible for reconstruction. Since the general way to obtain the epipolar, projective, and Euclidian geometries from point feature correspondences is already solved, here the emphasis is on the performance of the algorithms in the presense of noise. Kanatani's epipolar geometry estimation method is improved and this is experimentally validated. Regarding Bougnoux's Euclidian geometry estimation method, the initial linear solution is now obtained with less uncertainty and the non-linear minimization does no longer converge to a hidden solution. Experimental results are given to assess the system performance.
Motion control is one of the most critical factors in the design of a robot. The purpose of this paper is to describe the research for applying motion control principles for a mobile robot systems design, which is on ...
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ISBN:
(纸本)0819434302
Motion control is one of the most critical factors in the design of a robot. The purpose of this paper is to describe the research for applying motion control principles for a mobile robot systems design, which is on going at the University of Cincinnati Robotics Center. The mobile robot was constructed during the 1998-1999 academic year, and called BEARCAT II. Its design has inherited many features of its predecessor, BEARCAT I, such as vision guidance, sonar detection and digital control. In addition, BEARCAT II achieved many innovative motion control features as rotating sonar, zero turning radius (ZTR), current control loop, and multi-level controller design (conventional control and fuzzy logic control). This paper will focus on the motion control design, development and programming for the vehicle steering control and rotating sonar systems. The systems have been constructed and tested at the 1999 International Ground Robotics Competition with the Bearcat II running an obstacle course for 153.5 feet and finishing fourth in the competition. The significance of this work is in the increased understanding of robot control and the potential application of autonomous guided vehicle technology for industry, defense and medicine. Keywords: Motion control, motion behavior, compensation, mobile robots.
In the future, interaction between humans and personal robots will become increasingly important as robots will, more and more, operate as assistants in our everyday life. Because of this, there is a need for a conven...
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ISBN:
(纸本)0819434302
In the future, interaction between humans and personal robots will become increasingly important as robots will, more and more, operate as assistants in our everyday life. Because of this, there is a need for a convenient, flexible, and general-purpose technique that we can use to interact with robots. Moreover, the same technique should also be usable when we interact with embedded systems in smart environments. In this paper, we will describe a technique that allows us to use a single simple handheld control device to interact not only with personal robots, but also with ubiquitous embedded systems. When a new system, whether a mobile robot or a VCR, is encountered, the control device downloads a mobile code from the system and executes it. The mobile code then uses the services provided by the control device to create a virtual user interface that we can use to interact with the particular system. Our technique is flexible, simple, adaptive, and open. The technique draws much of its flexibility and simplicity from the mobile code. Adaptivity comes from the fact that the control device only needs minimal knowledge about each particular system. In addition, the technique does not place any restrictions on the type of mobile code that can be used. We will describe the architecture of the CUES system that utilizes our technique. We will also describe the architecture of the SMAF system, our test bed mobile code execution environment used in CUES. In addition, we will present a virtual user interface for a mobile robot that we can use to control the robot and to monitor its status information. The interface also operates as a terminal that we can use to access remote information in the Internet.
This article shows how graph and diagrammatic structures could evolve into the more abstract ones that carry knowledge about the originals in form of relations and hierarchies. They can play a role of context, or &quo...
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ISBN:
(纸本)0819434302
This article shows how graph and diagrammatic structures could evolve into the more abstract ones that carry knowledge about the originals in form of relations and hierarchies. They can play a role of context, or "measurement device", giving the ability to analyze. Such derivative structures can drive processes in distributed networks, like firing a spatio-temporal pattern, creating another structure, etc., therefore, performing top-bottom algorithms. In the mid-80 PDP group came closely to the problem of knowledge representation by distributed graphs called "schemata". Their models were based on the neural networks. I argue that the actual level of problems that neural network can solve is lower than required for knowledge representation. The "hardware unit" of intelligence could rather be a "neural assembly'' that combines both discrete and continuous features, and is able to perform both diagrammatic and graphs operations, being the basis of intelligence. The representation of such "neural assembly" as a fuzzy logic unit with active kernel and less active fuzzy boundaries is proposed. Such units can make logical operations spatially and temporarily, acting on a diagrammatic manner. Connections between the set of such activated units make spatio-temporal pattern really looking like a set of nodes connected via links on more abstract level. The article shows that image understanding is the area where derivative structures play important role, making images and scenes self-describing without any word description, and truly invariant to any transformations. That opens way to the new technologies in computervision and image databases.
Human visual system is properly suited for reliable and adequate volumic perception of natural environment. Volumic data flows coming from the outer physical space are easily acquired, transferred and processed by eye...
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ISBN:
(纸本)0819434302
Human visual system is properly suited for reliable and adequate volumic perception of natural environment. Volumic data flows coming from the outer physical space are easily acquired, transferred and processed by eye-brain system in real time. This relates also to the animals which use different complicated mechanisms of optical volumic data acquisition and can navigate safely at high speeds. Un the contrary machine vision systems utilizing currently the stereoscopic effect in attempt to achieve volumic data presentation are very slow, bulky and in a way inelegantly devised. The stereoscopy itself seems can hardly organize the adequate, real time volumic robot vision. Novel general principles of volumic vision were formulated recently by this author. They can be applied also to machines and used in the future rapidly navigating mobile robots. Volumic approach to vision seems much more logical for handling of volumic data flows. Along the lines of this approach and unified concept of volumic imaging it is quite natural to assume fine stratification in depth both for biological volumic data sensors and the necessity of fine stratification in depth for artificial ones. Volumic data sensors in robotics seem must be organized as finely stratified in depth structures. Finely stratified in depth volumic data sensor operating in real time might incorporate volumic gratings and use a special software to interpret the arriving volumic data flow. While the task is very difficult, success would permit to organize volumic robot vision in a different war and to create principally novel type of robotic system, ie, 'one-eyed robots'. Preliminary experiments were performed in this work. Complicated holographic gratings were obtained which might serve as components of a future volumic data sensor. Microphotographs of such gratings taken as horizontally stratified slices are presented.
The proceedings contains 53 papers from the SPIE conference on intelligentrobots and computervision XVII: algorithms, techniques, and Active vision. Topics discussed include: planetary rovers for long-range Mars sci...
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The proceedings contains 53 papers from the SPIE conference on intelligentrobots and computervision XVII: algorithms, techniques, and Active vision. Topics discussed include: planetary rovers for long-range Mars science and sample return;pose estimation;geometric and orthogonal moments;Shen-Castan and Canny-Deriche filters;Bayesian neural network learning;robot guidance;face recognition;wireless video monitoring and robot control;image processing for intelligent robotics;robot path planning, guidance and control;color computervision;3D visualization for intelligent robotics;active robotic vision;and image segmentation in computervision.
This paper describes two methods for feature extraction. The goal is to interpret the data obtained from sonar measurements of the robot's environment as geometric map primitives. The extracted primitives can be u...
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This paper describes two methods for feature extraction. The goal is to interpret the data obtained from sonar measurements of the robot's environment as geometric map primitives. The extracted primitives can be used to update the robot position and the global map. This is the process how the robot can explore an unknown environment. The first algorithm gathers sonar measurements into sensor-based map and then using computer-visiontechniques and morphological operations extracts geometric description of detected obstacles. The second method is started whenever the border tracking algorithm has been activated. This method uses raw sonar data as the input while obstacle border is robustly detected by the border tracking process. The algorithms have been verified with an experimental mobile robot at the Czech Technical University.
This paper describes a practical approach for environment perception using fusion of active ranging with a low-power laser and passive, stereo based ranging. A low-cost, coarse pitch linear detector is used, but still...
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ISBN:
(纸本)081942983X
This paper describes a practical approach for environment perception using fusion of active ranging with a low-power laser and passive, stereo based ranging. A low-cost, coarse pitch linear detector is used, but still sufficient distance accuracy for mobile robotics is achieved by using a new method of sub-pixel calibration. The device is intended for mobile robot or vehicle perception duties in obstacle detection and target position measurement.
Collision freeness is an essential feature in off-line programming of robots. It relates to safe and efficient operation, and becomes even more critical, when two or more robots are sharing the same work space, which ...
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ISBN:
(纸本)081942983X
Collision freeness is an essential feature in off-line programming of robots. It relates to safe and efficient operation, and becomes even more critical, when two or more robots are sharing the same work space, which is typical for so called holonic robot systems. Here we are reporting a simple and fast path planning algorithm based on configuration space method, suitable for holonic robot applications. The basic version of the algorithm can be found from the literature, and we have extended and modified it to improve its feasibility. Simulation and experimental tests have been carried out succesfully.
An intelligent robot is a remarkably useful combination of a manipulator, sensors and controls. The use of these machines in factory automation can improve productivity, increase product quality and improve competitiv...
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ISBN:
(纸本)081942983X
An intelligent robot is a remarkably useful combination of a manipulator, sensors and controls. The use of these machines in factory automation can improve productivity, increase product quality and improve competitiveness. This paper presents a discussion of recent technical and economic trends. Technically, the machines are faster, cheaper, more repeatable, more reliable and safer. The knowledge base of inverse kinematic and dynamic solutions and intelligent controls is increasing. More attention is being given by industry to robots, vision and motion controls. New areas of usage are emerging for service robots, remote manipulators and automated guided vehicles. Economically, the robotics industry now has a 1.1 billion-dollar market in the U.S. and is growing. Feasibility studies results are presented which also show decreasing costs for robots and unaudited healthy rates of return for a variety of robotic applications. However, the road from inspiration to successful application can be long and difficult, often taking decades to achieve a new product. A greater emphasis on mechatronics is needed in our universities. Certainly, more cooperation between government, industry and universities is needed to speed the development of intelligentrobots that will benefit industry and society.
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