Description
Excerpt from Structured Light Sensors for 3-D Robot Vision
A structured light or active illumination visual sensor is one which illuminates objects using non - uniform beams of light on which properties varying from point to point through the geometric extent of the beam have been impressed. Any observable property can be used to form such a beam; among properties which one might think of exploiting are intensity, polarisation, spectral distribution of optical energy, coherence, and (temporal) modulation. Structured light sensors can be used to achieve 3 - D vision, that is, to build visual sensors that report the true position in 3 - dimensional space of points on the surface of a body or bodies being observed. Besides giving information on object proximity, sensor output of this kind should be very useful for identifying the objects present in a scene and determining their positions and orientations.
The simplest form of structured light approach is the striped light scheme originally introduced by P. Will and K. Pennington of ibm Research. In this sensor (see Fig. 1) a plane P of light formed by passing collimated light from a source 8 through a Slit is used to illuminate a body B. The resulting illuminated stripe on the body B is observed through a camera C offset from the source S. Then the 3-d position of each illuminated point X can be calculated as the unique point of intersection of the plane P with the known line L from the camera through X. Note that L is known since it is determined geometrically by the point at which the image of X falls on the retina of C. (see Fig. 1, below.) We also suppose this wedge of light to be structured, in the sense that some measurable property Q is imposed upon its separate rays; this property is assumed to be constant in each vertical plane of the wedge W, but to vary monotonically from left to right across the wedge, which is to say monotonically with the geometric parameter h shown in Fig. 2, which defines the vertical plane in which a given point of W lies.
In the will-pennington scheme, the whole surface of the body B can be determined by panning the plane P over the whole visual field. An improved scheme, which allows this whole surface to be determined more rapidly, is as follows. Suppose that the body B is illuminated by a wedge W of light as in Fig. 2 below.
About the Publisher
Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com
This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
A structured light or active illumination visual sensor is one which illuminates objects using non - uniform beams of light on which properties varying from point to point through the geometric extent of the beam have been impressed. Any observable property can be used to form such a beam; among properties which one might think of exploiting are intensity, polarisation, spectral distribution of optical energy, coherence, and (temporal) modulation. Structured light sensors can be used to achieve 3 - D vision, that is, to build visual sensors that report the true position in 3 - dimensional space of points on the surface of a body or bodies being observed. Besides giving information on object proximity, sensor output of this kind should be very useful for identifying the objects present in a scene and determining their positions and orientations.
The simplest form of structured light approach is the striped light scheme originally introduced by P. Will and K. Pennington of ibm Research. In this sensor (see Fig. 1) a plane P of light formed by passing collimated light from a source 8 through a Slit is used to illuminate a body B. The resulting illuminated stripe on the body B is observed through a camera C offset from the source S. Then the 3-d position of each illuminated point X can be calculated as the unique point of intersection of the plane P with the known line L from the camera through X. Note that L is known since it is determined geometrically by the point at which the image of X falls on the retina of C. (see Fig. 1, below.) We also suppose this wedge of light to be structured, in the sense that some measurable property Q is imposed upon its separate rays; this property is assumed to be constant in each vertical plane of the wedge W, but to vary monotonically from left to right across the wedge, which is to say monotonically with the geometric parameter h shown in Fig. 2, which defines the vertical plane in which a given point of W lies.
In the will-pennington scheme, the whole surface of the body B can be determined by panning the plane P over the whole visual field. An improved scheme, which allows this whole surface to be determined more rapidly, is as follows. Suppose that the body B is illuminated by a wedge W of light as in Fig. 2 below.
About the Publisher
Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com
This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Details
Publisher - Forgotten Books
Author(s) - J. T. Schwartz
Hardback
Published Date -
ISBN - 9780331304909
Dimensions - 22.9 x 15.2 x 0.4 cm
Page Count - 19
Paperback
Published Date -
ISBN - 9781334254512
Dimensions -
Page Count -
Payment & Security
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.