We present a number of applications of optical grating technology for use in machine vision and industrial inspection and measurement applications. The gratings are based on an array of prisms that: are both very easy...
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ISBN:
(纸本)0819426407
We present a number of applications of optical grating technology for use in machine vision and industrial inspection and measurement applications. The gratings are based on an array of prisms that: are both very easy and very cheap to produce. Currently optical gratings are used in industry in temporal/spatial correlation systems using non-coherent white-light illumination Such systems require either the displacement of the object or the displacement of the grating in order to achieve the time signals required for evaluation. New developments in grating manufacturing techniques and electronic signal processing now enable us to electronically simulate and generate the signals required eliminating the requirement for grating or object motion. We also present a range sensor based on a split pupil methodology upon which we are developing a multiple-channel range sensor. We also highlight some of the work we are presently pursuing in multiple-layer gratings, We are investigating the Talbot and Lau self-imaging effects with hopes of using the results to preprocess images. We have also calculated the effect of multiple Bragg planes recorded into holographic materials, which can be used to produce local image transformations. Also summarized is some of the work based on an inverted retina model of the eye which uses multi-layer gratings placed before the photoreceptors to general trichromatic separation of Light and explain a number of physiological effects of vision.
The interpretation of the ''inverted'' retina of primates as an ''optoretina'' (a light cones transforming diffractive cellular 3D-phase grating) integrates the functional, structural, ...
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ISBN:
(纸本)0819426407
The interpretation of the ''inverted'' retina of primates as an ''optoretina'' (a light cones transforming diffractive cellular 3D-phase grating) integrates the functional, structural, and oscillatory aspects of a cortical layer. It is therefore relevant to consider prenatal developments as a basis of the macro-and micro-geometry of the inner eye. This geometry becomes relevant for the postnatal trichromatic: synchrony organization (TSO) as well as the adaptive levels of human vision (28 - 33). It will be shown that the functional performances, the trichromatisme in photopic vision, the monocular spatiotemporal 3D- and 4D-motion detection, as well as the Fourier optical image transformation. with extraction of invariances all became possible, To transform light cones into reciprocal gratings especially the spectral phase conditions in the eikonal of the geometrical optical imaging before the retinal 3D-grating become relevant first, then in the von Laue resp. reciprocal van Lane equation for 3D-grating optics inside the grating and finally in the periodicity of Talbot-/Fresnel-planes in the near-field behind the grating. It is becoming possible to technically realize - at least in same specific aspects - such a cortical optoretina sensor element with its typical hexagonal-concentric structure which leads to these visual functions.
Robotic exploration of the Martian surface will provide important scientific data on planetary climate, life history, and geologic resources. Ln particular, robotic arms will assist in the detailed visual inspection, ...
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ISBN:
(纸本)0819426407
Robotic exploration of the Martian surface will provide important scientific data on planetary climate, life history, and geologic resources. Ln particular, robotic arms will assist in the detailed visual inspection, instrumented analysis, extraction, and earth return of soil and rock samples. To this end, we are developing new robotic manipulation concepts for use on landers and rovers, wherein mass, volume, power and the ambient Mars environment are significant design constraints. Our earlier work led to MarsArmI, a 2.2 meter, 3-d.o.f. hybrid metal/composite, DC-motor actuated arm operating under coordinated joint-space control;NASA's Mars Surveyor '98 mission utilizes this design concept More recently, we have conceived and implemented new, all-composite, very light robot arms: MarsArmII, a 4.0 kilogram, 2.3 meter arm for lander operations, and MicroArm-I and MicroArm-2, two smaller 1.0+ kilogram, .7 meter rover arms for mobile sample acquisition and Mars sample return processing. Features of these arms include our creation of new 3D machined composites for critical load-bearing parts;actuation by high-torque density ultrasonic motors;and visually-designated inverse kinematics positioning with contact force adaptation under a novel task-level, dexterous controls paradigm, Our demonstrated results include robotic trenching, sample grasp-manipulation-and-transfer, and fresh rock surface exposure-probing via the science operator's ''point-and-shoot'' visual task designation in a stereo workspace. Sensor-referenced control capabilities include red-time adaptation to positioning error and environmental uncertainties (e.g., variable soil resistance and impediments), and the synthesis of power optimal trajectories for free space manipulation.
We report on the development of new mobile robots for Mars exploration missions. These ''lightweight survivable rover (LSR)'' systems are of potential interest to both space and terrestrial application...
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ISBN:
(纸本)0819426407
We report on the development of new mobile robots for Mars exploration missions. These ''lightweight survivable rover (LSR)'' systems are of potential interest to both space and terrestrial applications, and ape distinguished from more conventional designs by their use of new composite materials, collapsible running gear, integrated thermal-structural chassis, and other mechanical features enabling improved mobility and environmental robustness at reduced mass, volume, and power. Our first demonstrated such rover architecture, LSR-1, introduces running gear based on 2D composite struts and 3D machined composite joints, a navel collapsible hybrid composite-aluminum wheel design, a unit-body structural-thermal chassis with improved internal temperature isolation and stabilization, and a spot-pushbroom laser/CCD sensor enabling accurate, fast hazard detection and terrain mapping. LSR-1 is a similar to .7 x 1.0 meter(Lambda)2(WxL) footprint six-wheel (20 cm dia.) rocker-bogie geometry vehicle of similar to 30 cm ground clearance, weighing only 7 kilograms with an onboard 3 kilogram multi-spectral imager and spectroscopic photometer. By comparison, NASA/JPL's recently flown Mars Pathfinder rover Sojourner is an 11+ kilogram flight experiment (carrying a 1 kg APXS instrument) having similar to .45 x.6 meter(Lambda)2 (WxL) footprint and 15 cm ground clearance, and about half the warm electronics enclosure (WEE) volume with twice the diurnal temperature swing (-40 to +40 degrees C) of LSR-1 in nominal Mars environments. We are also developing a new, smaller 5 kilogram class LSR-type vehicle for Mars sample return - the travel to, localization of, pick-up, and transport back to an Earth return ascent vehicle of a sample cache collected by earlier science missions. This Sample Retrieval Rover R&D prototype has a. completely collapsible mobility system enabling rover stowage to similar to 25% operational volume, as well an actively articulated axle, allowing changeable pose of
The face recognition, one of the most important ability of intelligentvision, are discussed in this paper. A new idea of model-based processing are presented. The algorithms of face modeling, global matching and fine...
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ISBN:
(纸本)0819423068
The face recognition, one of the most important ability of intelligentvision, are discussed in this paper. A new idea of model-based processing are presented. The algorithms of face modeling, global matching and fine matching, and feature points extraction etc. are given Finally, a rapid and robust scheme for human face recognition are resulted.
The ability to assess the severity of dermatoses by measuring the area of involvement is important in both clinical practice and research, but it has been shown that physicians, nurses and other groups are unable to d...
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ISBN:
(纸本)0819423068
The ability to assess the severity of dermatoses by measuring the area of involvement is important in both clinical practice and research, but it has been shown that physicians, nurses and other groups are unable to do this accurately. A common practice in current use is the 'rule of nine' method, but wide variations have been found between observers' estimates. The purpose of this work was to test and demonstrate the feasibility of a computervision technique for measuring the area of involvement in skin diseases by developing a system for psoriasis area assessment from slides which can be operated in an image processing environment. The exact percentage of the slide area involved varied from 1% to 59%, thus providing realistic material for the system. The system proved sufficiently accurate, and the techniques evidently have a potential for inclusion as parts of a more accurate and rapid method for area measurement in the case of skin diseases.
We discuss the uniqueness of 3-D 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 ...
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ISBN:
(纸本)0819423068
We discuss the uniqueness of 3-D 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 (or concave) shape solutions usually exist for a pyramid with three or more visible facets. However, if interreflection distribution is used as a constraint to limit the shape of polyhedron (for a concave 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.
Oue goal is to mar ch primitives of a pair of images, thereby solving the correspondence problem, in order to estimate depths of 3D scene points from the relative distance (disparity) between matched features. We prop...
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ISBN:
(纸本)0819423068
Oue goal is to mar ch primitives of a pair of images, thereby solving the correspondence problem, in order to estimate depths of 3D scene points from the relative distance (disparity) between matched features. We propose a feature-based approach to solve the correspondence problem by minimizing an appropriate energy function where constraints on radiometric similarity and projective geometric invariance of coplanar points are defined. The method can be seen as a correlation based approach which take into account the projective invariance of coplanar points in computing the optimal matches.
Three-dimensional (3D) reconstruction of highly textured surfaces on unvegetated (rock-like) terrain is of major interest for stereo vision based mapping applications. We describe a prototype system for automatic mode...
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ISBN:
(纸本)0819423068
Three-dimensional (3D) reconstruction of highly textured surfaces on unvegetated (rock-like) terrain is of major interest for stereo vision based mapping applications. We describe a prototype system for automatic modeling of such scenes. It is based on two frame CCD cameras, which are tightly attached to each other ensuring constant relative orientation. One camera is used to acquire known reference points to get the exterior orientation of the system, the other records the surface images. The system is portable to keep image acquisition as short as possible. Automatic calibration using the images acquired by the calibration camera permits the computation of exterior orientation parameters of the surface camera via a transformation matrix. A robust matching method providing dense disparities together with a flexible reconstruction algorithm renders an accurate grid of 3D points on arbitrarily shaped surfaces. The results of several stereo reconstructions are merged. Projection onto the global shape allows easy evaluation of volumes, and thematic mapping with respect to the desired surface geometry in construction processes. We report on accuracy and emphasize on the practical usage. It is shown that the prototype system is able to generate a proper data set of surface descriptions that is accurate and dense enough to serve as documentation, planning and accounting basis.
Active vision is identified by a closed loop linking sensing with acting. Thus, an active vision system's behaviour is directly determined by what it senses. To date however, the responses produced by active visio...
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ISBN:
(纸本)0819423068
Active vision is identified by a closed loop linking sensing with acting. Thus, an active vision system's behaviour is directly determined by what it senses. To date however, the responses produced by active vision systems have tended to be relatively low-level, generally designed to facilitate improved sensing, by enhancing the duration or speed of object tracking, for example, or optimising the focussed application of more intensive image processing. This is probably adequate if the active vision system is designed as a front end to other processes or to specialised application systems, or if it is a demonstration in support of a theoretical vision model. However, this leaves unanswered the problems of i) how to select an appropriate action when many different alternatives are available, and ii) how best to modify the behavioural repertoire of the system. These problems are especially important in two situations: firstly, when an autonomous system faces a novel situation and must respond adaptively without the benefit of a priori knowledge, and secondly, when systems attempt higher levels of perception and response, and links between the absolute properties of the incoming image data and the actual objects of perception become increasingly attenuated. This paper discusses methods for linking learning with active vision so that the behaviour of the system is optimised over time for the achievement of goals. We argue the necessity of system goals in learning vision systems, and discuss methods for propagating goals through all levels of loose hierarchies. In the last section we outline an architecture in which high and low level perception operate interactively and in parallel.
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