An automatic raw material selector into 3-4 groups depending on the crystal shape is developed. As signs of selection there are used dimensions of the crystal image, position of the image center in the bearing plan as...
详细信息
ISBN:
(纸本)0819423068;9780819423061
An automatic raw material selector into 3-4 groups depending on the crystal shape is developed. As signs of selection there are used dimensions of the crystal image, position of the image center in the bearing plan as well as dimensions and proportion of two interperpendicular chords crossing the image center. The device sorts out into 3-4 groups 8 crystals per second.
This paper describes the use of color segmentation to assist the detection of blemishes and other defects on fruit. It discusses the advantages and disadvantages of different color spaces including RGB and HSI and dif...
详细信息
ISBN:
(纸本)0819423068;9780819423061
This paper describes the use of color segmentation to assist the detection of blemishes and other defects on fruit. It discusses the advantages and disadvantages of different color spaces including RGB and HSI and different supervised learning techniques including maximum likelihood, nearest neighbor and neural networks. It then compares the performance of various combinations of these on the same training and test set. A selection of images segmented by the best combination is presented and conclusions made.
Current developments in the field of automated assembly systems show an increasing interest in systems that are flexible in both CAD based product design and CAD based assembly. For the application addressed in this p...
详细信息
ISBN:
(纸本)0819423068;9780819423061
Current developments in the field of automated assembly systems show an increasing interest in systems that are flexible in both CAD based product design and CAD based assembly. For the application addressed in this paper, coupling the vision system and a CAD database is of prime importance in order to achieve the required automatic reconfiguration of the assembly cell when new parts are defined. This paper presents a 3D CAD-based vision system for obtaining 3D data about the scene. After the images are acquired, edge detection is preformed and the detected edges are stored as chaincodes. Following that, a stereo vision algorithm is applied for finding the recognition features. The output are lists of features that are combined into a 3D wireframe representing the scene. The recognition algorithm takes the observed wireframe outputs from the stereo vision system, and compares them with a set of model wireframes derived from previous models, in order to select the 'best match', where the previous models used for recognition are derived from a product data model (PDM). The PDM is an interface between the CAD database and the recognition system, which allows the automatic generation of new models when new parts are introduced into the system. The vision system described in this paper is part of an intelligent robotic assembly cell, where the aim is to build a flexible intelligent robotic assembly cell, such that robots would be able to automatically assemble a random variety of small-batch products.
Robust range estimation is one of the most important tasks in mobile robotics. This paper presents a new optical arrangement for utilizing the previously known 'depth from defocus' principle. The arrangement m...
详细信息
ISBN:
(纸本)0819423068;9780819423061
Robust range estimation is one of the most important tasks in mobile robotics. This paper presents a new optical arrangement for utilizing the previously known 'depth from defocus' principle. The arrangement makes it possible to apply standard video lenses and camera modules for making a compact range camera system. Real-time processing is made possible with a single-board DSP card.
We discuss the uniqueness of 3D shape recovery of a polyhedron from a single shading image, and propose an approach to uniquely determine the concave shape solution by using interreflections as a constraint. We show t...
详细信息
ISBN:
(纸本)0819423068;9780819423061
We discuss the uniqueness of 3D shape recovery of a polyhedron from a single shading image, and propose an approach to uniquely determine the concave shape solution by using interreflections as a constraint. We show that if interreflection distribution is not considered, multiple convex shape solutions usually exist for a pyramid with three or more visible facets. However, if interreflection distribution is used as a constraint to limits the shape of polyhedron, polyhedral shape can be uniquely determined. Interreflections, which were considered to be deleterious in conventional approaches, are an important constraint for shape-from-shading.
Knowledge of the bidirectional optical scatter function of surfaces comprising a 2D scene is used to predict and optimize characteristics of a digitally captured image of the scene. Mathematical expressions that descr...
详细信息
ISBN:
(纸本)0819423068;9780819423061
Knowledge of the bidirectional optical scatter function of surfaces comprising a 2D scene is used to predict and optimize characteristics of a digitally captured image of the scene. Mathematical expressions that describe certain image properties including contrast, brightness, glare, etc., are developed from the scatter functions. It is these mathematical expressions that are maximized or minimized with respect to a set of coordinates used to describe the orientation of a collimated light source and imaging system relative to the scene. In this way, it is shown how illumination can be analytically prescribed to attenuated or accentuated certain properties of digital images without the trial-and-error procedure currently in practice.
This paper addresses the problem of local navigation for an autonomous guided vehicle (AGV) in a structured environment that contains static and dynamic obstacles. Information about the environment is obtained via a C...
详细信息
ISBN:
(纸本)0819423068;9780819423061
This paper addresses the problem of local navigation for an autonomous guided vehicle (AGV) in a structured environment that contains static and dynamic obstacles. Information about the environment is obtained via a CCD camera. The problem is formulated as a dynamic feedback control problem in which speed and steering decisions are made on the fly while the AGV is moving. A decision element (DE) that uses local information is proposed. The DE guides the vehicle in the environment by producing appropriate navigation decisions. Dynamic models of a three-wheeled vehicle for driving and steering mechanisms are derived. The interaction between them is performed via the local feedback DE. A controller, based on fuzzy logic, is designed to drive the vehicle safely in an intelligent and human-like manner. The effectiveness of the navigation and control strategies in driving the AGV is illustrated and evaluated.
In this paper, steps of the physically-based modeling technique are revisited. Proposals for enhancing computational burden are implemented. Force derived from the distance between the model profile and the object pro...
详细信息
ISBN:
(纸本)0819423068;9780819423061
In this paper, steps of the physically-based modeling technique are revisited. Proposals for enhancing computational burden are implemented. Force derived from the distance between the model profile and the object profile has proven sufficient for shape recovery purposes while the speed of the fitting process is reduced dramatically. In order to give machines the ability to detect surface irregularities as well as their sizes, a threshold potential function force is applied to excite the surface nodal mesh with good time requirements. Implementation details as well as sample examples are introduced.
Based on the concept of object- and behavior-oriented stereo vision, a method is introduced which enables a robot manipulator to handle two distinct types of objects. It uses an uncalibrated stereo vision system and a...
详细信息
ISBN:
(纸本)0819423068;9780819423061
Based on the concept of object- and behavior-oriented stereo vision, a method is introduced which enables a robot manipulator to handle two distinct types of objects. It uses an uncalibrated stereo vision system and allows a direct transition from image coordinates to motion control commands of a robot. An object can be placed anywhere in the robot's 3D work space which is in the field of view of both cameras. The objects to be manipulated can either be of flat cylindrical or elongate shape. Results gained from real-world experiments are discussed.
Augmented reality is a term used to describe systems in which computer-generated information is superimposed on top of the real world; for example, through the use of a see-through head-mounted display. A human user o...
详细信息
ISBN:
(纸本)0819423068;9780819423061
Augmented reality is a term used to describe systems in which computer-generated information is superimposed on top of the real world; for example, through the use of a see-through head-mounted display. A human user of such a system could still see and interact with the real world, but have valuable additional information, such as descriptions of important features or instructions for performing physical tasks, superimposed on the world. For example, the computer could identify and overlay them with graphic outlines, labels, and schematics. The graphics are registered to the real-world objects and appear to be 'painted' onto those objects. Augmented reality systems can be used to make productivity aids for tasks such as inspection, manufacturing, and navigation. One of the most critical requirements for augmented reality is to recognize and locate real-world objects with respect to the person's head. Accurate registration is necessary in order to overlay graphics accurately on top of the real-world objects. At the Colorado School of Mines, we have developed a prototype augmented reality system that uses head-mounted cameras and computervisiontechniques to accurately register the head to the scene. The current system locates and tracks a set of pre-placed passive fiducial targets placed on the real-world objects. The system computes the pose of the objects and displays graphics overlays using a see-through head-mounted display. This paper describes the architecture of the system and outlines the computervisiontechniques used.
暂无评论