ES2369802A1 - Dimensional pattern for scanner and photogrammetric laser systems. (Machine-translation by Google Translate, not legally binding) - Google Patents
Dimensional pattern for scanner and photogrammetric laser systems. (Machine-translation by Google Translate, not legally binding) Download PDFInfo
- Publication number
- ES2369802A1 ES2369802A1 ES201000591A ES201000591A ES2369802A1 ES 2369802 A1 ES2369802 A1 ES 2369802A1 ES 201000591 A ES201000591 A ES 201000591A ES 201000591 A ES201000591 A ES 201000591A ES 2369802 A1 ES2369802 A1 ES 2369802A1
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- Prior art keywords
- photogrammetric
- dimensional pattern
- systems
- scanner
- pockets
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/02—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness
- G01B21/04—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness by measuring coordinates of points
- G01B21/042—Calibration or calibration artifacts
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C25/00—Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
Abstract
Description
Patrón dimensional para sistemas láser escáner y fotogramétricos.Dimensional pattern for laser scanner systems and photogrammetric
La presente invención se refiere al desarrollo de un patrón que sirve para la verificación dimensional de sistemas tipo láser escáner y fotogramétricos, obteniendo la precisión, exactitud y deriva de los mismos, así como comprobando su resolución horizontal y vertical en la medición de relieves como hendiduras o salientes.The present invention relates to the development of a pattern that serves for the dimensional verification of systems laser type scanner and photogrammetric, obtaining the precision, accuracy and drift of them, as well as checking their resolution horizontal and vertical in the measurement of reliefs as slits or outgoing
Los sistemas de medición basados en fotogrametría y láser escáner permiten la obtención de nubes de puntos con coordenadas espaciales de la superficie de objetos para posteriormente obtener modelos tridimensionales de los mismos. Estas aplicaciones resultan de utilidad en sectores como la arquitectura, ingeniería civil, conservación del patrimonio, geodesia, e incluso en industrias como la naval o aeronáutica.Measuring systems based on photogrammetry and laser scanner allow obtaining clouds of points with spatial coordinates of the surface of objects for subsequently obtain three-dimensional models of them. These applications are useful in sectors such as architecture, civil engineering, heritage conservation, geodesy, and even in industries such as naval or aeronautical.
Las técnicas de fotogrametría digital se basan
en la utilización de cámaras réflex o compactas digitales en las
cuales se conocen u obtienen previamente los parámetros
correspondientes a su orientación interna como por ejemplo las
distorsiones radial y tangencial de la lente, coordenadas del punto
principal, distancia focal de la lente, tamaño del sensor, etc.
Estos parámetros en definitiva modelan la geometría del sistema
óptico de la cámara y establecen una relación entre el sistema de
coordenadas de la imagen y el sistema de coordenadas del sensor.
Estos parámetros combinados con la orientación externa de la
imágenes obtenidas del objeto y empleando la algorítmica adecuada,
basada en gran parte en el principio de colinealidad, permiten la
obtención de las coordenadas espaciales tridimensionales del objeto.
La orientación externa establece una relación entre el sistema de
coordenadas del sensor y el correspondiente al mundo real. El modelo
obtenido se debe dimensionar empleando por ejemplo dianas de control
de coordenadas geométricas conocidas o barras de escala. La
fotogrametría está íntimamente unida a tecnologías como la visión
artificial, procesado digital de imagen o la óptica, que contribuyen
a su desarrollo y
avance.Digital photogrammetry techniques are based on the use of DSLR or compact digital cameras in which the parameters corresponding to their internal orientation are known or obtained previously, such as radial and tangential distortions of the lens, coordinates of the main point, focal length of the lens, sensor size, etc. These parameters ultimately model the geometry of the camera's optical system and establish a relationship between the image coordinate system and the sensor coordinate system. These parameters combined with the external orientation of the images obtained from the object and using the appropriate algorithmic, based largely on the principle of collinearity, allow obtaining the three-dimensional spatial coordinates of the object. External orientation establishes a relationship between the sensor coordinate system and that corresponding to the real world. The model obtained must be sized using, for example, known geometric coordinate control targets or scale bars. Photogrammetry is closely linked to technologies such as artificial vision, digital image processing or optics, which contribute to its development and
Advance.
En la actualidad casi todos los desarrollos
relacionados con la metrología en sistemas fotogramétricos se han
ocupado de factores como por ejemplo la fabricación de elementos
ópticos de alta calidad para disminuir las distorsiones ópticas,
incrementar el número de píxeles de los sensores para obtener
imágenes con mayor resolución espacial, establecer procedimientos
para la correcta calibración interna de las cámaras, desarrollo de
algoritmos fotogramétricos para mejorar la orientación externa de
las fotografías del objeto y mejorar las coordenadas
tridimensionales obtenidas o aplicar procesado digital de imagen
para automatizar el proceso de búsqueda de puntos fiduciales. A
pesar de los grandes desarrollos realizados no existen
comercialmente patrones tridimensionales orientados a este tipo de
tecnología. Dichos patrones deberían permitir que los usuarios de
estos equipos comprueben las especificaciones metrológicas
(precisión, exactitud y resolución) ofrecidas por los fabricantes de
cámaras y desarrolladores de software fotogramétrico, y por otra
parte, verificar el sostenimiento de las mismas durante la vida útil
de los equipos
(deriva).Nowadays almost all the developments related to metrology in photogrammetric systems have dealt with factors such as the manufacture of high quality optical elements to reduce optical distortions, increase the number of pixels of the sensors to obtain images with higher resolution spatial, establish procedures for the correct internal calibration of the cameras, development of photogrammetric algorithms to improve the external orientation of the photographs of the object and improve the three-dimensional coordinates obtained or apply digital image processing to automate the process of searching for fiducial points. Despite the great developments made, there are no commercially three-dimensional patterns oriented to this type of technology. These patterns should allow users of these devices to check the metrological specifications (precision, accuracy and resolution) offered by camera manufacturers and photogrammetric software developers, and, on the other hand, verify the maintenance of the same during the life of the devices. equipment
(drift).
Los sistemas láser escáner consisten en la combinación de un distanciómetro láser para la medida de distancia con dos espejos móviles a partir de los que se obtienen los ángulos cenital y acimutal. Esto hace que la superficie del objeto se sitúe en un sistema de coordenadas de tipo esférico que después se puede fácilmente convertir a cartesiano. A nivel metrológico se ha trabajado mucho en la obtención de distanciómetros más precisos, encoders de alta precisión para obtener mayor calidad en la medición de los ángulos, modelado de los errores típicos del sistema como por ejemplo el error lineal de rango, errores periódicos en la medición de distancia, errores de colimación, errores en la medida de ángulos, etc.The laser scanner systems consist of combination of a laser distance meter for distance measurement with two moving mirrors from which the angles are obtained zenithal and azimuthal. This causes the surface of the object to be located in a spherical coordinate system that can later be Easily convert to Cartesian. At the metrological level it has worked hard to obtain more precise distance meters, High precision encoders for better measurement quality of angles, modeling of typical system errors as per example linear range error, periodic measurement errors away, collimation errors, errors to the extent of angles, etc.
De la misma forma que con los sistemas fotogramétricos, no existen patrones tridimensionales ni procedimientos de verificación normalizados que permitan a los usuarios comprobar las especificaciones metrológicas ofrecidas por los fabricantes de este tipo de instrumentación, así como las derivas existentes durante la vida útil de los instrumentos.In the same way as with the systems photogrammetric, there are no three-dimensional patterns or standardized verification procedures that allow Users check the metrological specifications offered by the manufacturers of this type of instrumentation, as well as the existing drifts during the life of the instruments.
En la presente patente se muestra un patrón dimensional versátil que se puede aplicar indistintamente a sistemas fotogramétricos o láser escáner y que permitirá comprobar las especificaciones metrológicas de los mismos: exactitud, precisión, resolución y deriva.In the present patent a pattern is shown Versatile dimensional that can be applied interchangeably to systems photogrammetric or laser scanner and that will allow you to check the Metrological specifications thereof: accuracy, precision, resolution and drift.
El patrón dimensional aquí desarrollado permite verificar la exactitud y precisión de los sistemas láser escáner y fotogramétricos en rangos variables a través de la medición de distancias conocidas entre centros de esferas fijas sobre un bloque. Para ello, a partir de las coordenadas geométricas referidas a la superficie de las esferas se extraen los centros de las mismas empleando un ajuste por mínimos cuadrados o similar. Las distancias entre centros dan lugar a distancias geométricas hasta un rango máximo materializado por la longitud entre las coordenadas de los centros de las esferas de los extremos. Evaluando la repetitividad de las medidas se obtendrá la desviación típica de los datos obtenidos que será representativa de la precisión del sistema. Por otra parte, comparando los valores de distancia calculados frente a los previamente certificados por otro procedimiento metrológicamente superior, como por ejemplo con una máquina de medición por coordenadas, se podrá evaluar la exactitud del sistema. De forma similar, si se guarda un histórico con las medidas observadas y éstas se repiten a lo largo del tiempo, se podrá observar la evolución de la precisión y exactitud del equipo durante su vida útil (deriva).The dimensional pattern developed here allows verify the accuracy and precision of the laser scanner systems and photogrammetric in variable ranges through the measurement of known distances between centers of fixed spheres on a block. To do this, from the geometric coordinates referred to the surface of the spheres the centers of the same are extracted using an adjustment for least squares or similar. The distances between centers give rise to geometric distances up to a range maximum materialized by the length between the coordinates of the centers of the spheres of the extremes. Evaluating repeatability The standard deviation of the data will be obtained from the measurements obtained that will be representative of the accuracy of the system. By other part, comparing the calculated distance values against those previously certified by another metrologically procedure top, such as with a measuring machine for coordinates, the accuracy of the system can be evaluated. So similar, if a history is kept with the measures observed and these are repeated over time, you can observe the evolution of the precision and accuracy of the equipment during its life useful (drift).
Además, el patrón también permite la determinación de la resolución vertical y horizontal de dichos sistemas en la medición de relieve, tanto en salientes, materializados físicamente por cubos de diferentes dimensiones mecanizados sobre un plano de referencia, como en la medición de hendiduras, materializadas por cajeras mecanizadas respecto a un plano de referencia. La resolución tanto en la medición de salientes como de hendiduras vendrá dada por la distancia geométrica menor que es capaz de detectarse en cada uno de los ejes. En el caso de la resolución vertical esta magnitud se obtendrá a través de la distancia entre dos planos. Uno de los planos proviene en ambos casos, salientes y hendiduras, de un ajuste por mínimos cuadrados de los puntos geométricos situados en la superficie de referencia. El otro plano, dependiendo del caso, proviene de la superficie superior de los cubos o la inferior de las cajeras. En el caso de la resolución horizontal se puede utilizar un método basado en extraer la distancia horizontal entre el máximo y el mínimo de la función derivada de las coordenadas verticales sobre las coordenadas horizontales.In addition, the pattern also allows determination of the vertical and horizontal resolution of said relief measurement systems, both on projections, physically materialized by cubes of different dimensions machined on a reference plane, as in the measurement of slits, materialized by mechanized pockets with respect to a reference plane The resolution both in measuring outgoing as of slits it will be given by the geometric distance less than It is capable of being detected in each of the axes. In the case of vertical resolution this magnitude will be obtained through the distance between two planes. One of the planes comes in both cases, protrusions and indentations, of an adjustment by least squares of the geometric points located on the reference surface. He another plane, depending on the case, comes from the upper surface of the cubes or the bottom of the pockets. In the case of horizontal resolution you can use a method based on extract the horizontal distance between the maximum and the minimum of the function derived from vertical coordinates over coordinates horizontal.
La distancia entre cubos debe ser suficiente para evitar efectos de sombra entre las diversas fotografías que se realicen al verificar una técnica fotogramétrica.The distance between cubes must be sufficient to avoid shadow effects between the various photographs that are perform when verifying a photogrammetric technique.
El patrón es portátil y se puede sujetar con un trípode de los empleados típicamente en topografía, que permitirá su desplazamiento para comprobar sus características metrológicas a distancias y ángulos diferentes entre los equipos de medición y el patrón.The pattern is portable and can be held with a tripod of employees typically in topography, which will allow their displacement to check its metrological characteristics to different distances and angles between the measuring equipment and the Pattern.
El patrón dispone también de cajeras inferiores sin objetivo metrológico, pero con la función importante de aligerar peso en el sistema.The pattern also has lower pockets without a metrological objective, but with the important function of lightening weight in the system.
La principal ventaja que presenta esta invención consiste en que permitirá de una forma sencilla que los usuarios de equipos láser escáner y fotogramétricos verifiquen las especificaciones metrológicas de dichos sistemas tanto en el momento de su compra como el mantenimiento de las mismas durante su vida útil. Además, el patrón está pensado para minimizar los escaneados y fotografías necesarias para la verificación de los sistemas y se puede utilizar de forma portátil.The main advantage of this invention is that it will allow users to easily laser scanner and photogrammetric equipment verify the metrological specifications of such systems both at the time of your purchase as the maintenance of them during your life Useful. In addition, the pattern is designed to minimize scanning and necessary photographs for the verification of the systems and You can use it portable.
Para una mejor comprensión de cuanto queda descrito en la presente memoria, se acompañan los siguientes dibujos.For a better understanding of how much is left described herein, the following are accompanied drawings.
La figura 1 muestra una vista del patrón dimensional en la que se observan las esferas para la medición de exactitud, precisión y deriva en la medida de distancia, los cubos para la determinación de la resolución en la medida de salientes y las cajeras de la parte inferior para la disminución del peso. La figura 2 muestra una vista en la que destacan, además de las esferas y cajeras anteriormente mencionadas, otras cajeras de ancho progresivo que permiten obtener la resolución en la medición de hendiduras.Figure 1 shows a view of the pattern dimensional in which the spheres for the measurement of accuracy, precision and drift in distance measurement, the cubes for the determination of the resolution in the measure of projections and the bottom pockets for weight reduction. The Figure 2 shows a view that highlights, in addition to the spheres and previously mentioned pockets, other wide pockets progressive that allow to obtain the resolution in the measurement of slits
El patrón dimensional para sistemas láser escáner y fotogramétricos posee un bloque (1) preferentemente de aluminio para minimizar en lo posible el peso del mismo manteniendo rigidez estructural. El material más indicado es el aluminio porque resulta fácilmente mecanizable y, aunque sufre dilataciones superiores a materiales como el acero, éstas serán despreciables frente a las características metrológicas que presentan los sistemas láser escáner y fotogramétricos con resoluciones típicamente por encima del milímetro. En la parte superior de dicho bloque de aluminio (1) se ensamblan 5 esferas (2) de nylon, que permitirán verificar la exactitud, precisión y deriva de los sistemas de medición aquí tratados mediante la obtención de varias distancias (rango inferior - distancia entre primera y segunda esfera y rango superior - distancia entre primera y quinta esfera). El acoplamiento entre las esferas y el bloque de aluminio se realiza a través de anillas toroidales (3) también fabricadas en nylon y un adhesivo tipo epoxi, de forma que se incrementa la superficie de contacto entre ambos y se mejora su estabilidad mecánica.The dimensional pattern for laser systems scanner and photogrammetric has a block (1) preferably of aluminum to minimize its weight while maintaining structural rigidity The most suitable material is aluminum because It is easily machinable and, although it undergoes dilatation superior to materials such as steel, these will be negligible against the metrological characteristics presented by the systems laser scanner and photogrammetric with resolutions typically by over the millimeter On top of said block of Aluminum (1) 5 spheres (2) of nylon are assembled, which will allow verify the accuracy, precision and drift of the systems measurement treated here by obtaining several distances (lower range - distance between first and second sphere and range upper - distance between first and fifth sphere). The coupling between the spheres and the aluminum block is done through toroidal rings (3) also made of nylon and an adhesive epoxy type, so that the contact surface is increased between both and its mechanical stability is improved.
Los cubos (4) para la medición de la resolución horizontal y vertical en la medida de salientes se mecanizan directamente sobre el bloque de aluminio, de forma que sus dimensiones en los tres ejes disminuyen progresivamente. De la misma forma las cajeras (5) para la medición de la resolución en hendiduras también disminuyen paulatinamente su ancho en uno de los ejes horizontales, mientas que el otro eje horizontal y el eje vertical se mantienen constantes. Esta solución se adopta para disminuir en lo posible el peso del sistema y aprovechar el espacio existente. De la misma forma se mecanizan unas cajeras en la parte inferior (6) para contribuir a la disminución de peso. El hecho de que tanto los cubos (4) para la medición de resolución de salientes como las cajeras (6) para la medición de resolución en hendiduras estén mecanizados sobre el mismo bloque, le conferirá al sistema gran estabilidad mecánica.The cubes (4) for the resolution measurement horizontal and vertical as projections are machined directly on the aluminum block, so that its dimensions in the three axes decrease progressively. Of the same form the pockets (5) for measuring the resolution in slits also gradually decrease their width in one of the horizontal axes, while the other horizontal axis and the axis Vertical remain constant. This solution is adopted to reduce as much as possible the weight of the system and take advantage of the space existing. In the same way some pockets are machined in the part lower (6) to contribute to weight loss. The fact of that both the cubes (4) for the measurement of protrusion resolution as the pockets (6) for the measurement of slit resolution are mechanized on the same block, it will confer on the system great mechanical stability
Claims (3)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ES201000591A ES2369802B1 (en) | 2010-05-07 | 2010-05-07 | DIMENSIONAL PATTERN FOR LASER SCANNER AND PHOTOGRAMETRIC SYSTEMS. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ES201000591A ES2369802B1 (en) | 2010-05-07 | 2010-05-07 | DIMENSIONAL PATTERN FOR LASER SCANNER AND PHOTOGRAMETRIC SYSTEMS. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| ES2369802A1 true ES2369802A1 (en) | 2011-12-07 |
| ES2369802B1 ES2369802B1 (en) | 2012-06-26 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| ES201000591A Active ES2369802B1 (en) | 2010-05-07 | 2010-05-07 | DIMENSIONAL PATTERN FOR LASER SCANNER AND PHOTOGRAMETRIC SYSTEMS. |
Country Status (1)
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| ES (1) | ES2369802B1 (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29722450U1 (en) * | 1997-12-19 | 1998-03-26 | Leitz Brown & Sharpe Mestechni | Device for checking the geometric accuracy of a coordinate measuring machine |
| US5983512A (en) * | 1995-03-06 | 1999-11-16 | Trapet; Eugen | Reference object for coordinate measuring machines and machine tools |
| JP2002039742A (en) * | 2000-07-27 | 2002-02-06 | National Institute Of Advanced Industrial & Technology | Combination type calibration gauge |
| US6493957B1 (en) * | 1999-06-18 | 2002-12-17 | Japan As Represented By Director General Of Agency Of Industrial Science And Technology | Ball step gauge |
| JP2003302202A (en) * | 2002-04-09 | 2003-10-24 | National Institute Of Advanced Industrial & Technology | Performance evaluation method of multidimensional coordinate measuring machine, calibration gage and fixture of calibration gage of multidimensional coordinate measuring machine |
| DE10222575A1 (en) * | 2002-05-17 | 2003-11-27 | Volkswagen Ag | DMIS compatibility test for coordinate measuring machines, uses standard test piece with alignment balls and range of standard geometric shapes |
| US20040036867A1 (en) * | 2000-05-15 | 2004-02-26 | Ralf Jedamzik | One-dimensional calibration standard |
| CN101526336A (en) * | 2009-04-20 | 2009-09-09 | 陈炳生 | Calibration method of linear structured light three-dimensional visual sensor based on measuring blocks |
-
2010
- 2010-05-07 ES ES201000591A patent/ES2369802B1/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5983512A (en) * | 1995-03-06 | 1999-11-16 | Trapet; Eugen | Reference object for coordinate measuring machines and machine tools |
| DE29722450U1 (en) * | 1997-12-19 | 1998-03-26 | Leitz Brown & Sharpe Mestechni | Device for checking the geometric accuracy of a coordinate measuring machine |
| US6493957B1 (en) * | 1999-06-18 | 2002-12-17 | Japan As Represented By Director General Of Agency Of Industrial Science And Technology | Ball step gauge |
| US20040036867A1 (en) * | 2000-05-15 | 2004-02-26 | Ralf Jedamzik | One-dimensional calibration standard |
| JP2002039742A (en) * | 2000-07-27 | 2002-02-06 | National Institute Of Advanced Industrial & Technology | Combination type calibration gauge |
| JP2003302202A (en) * | 2002-04-09 | 2003-10-24 | National Institute Of Advanced Industrial & Technology | Performance evaluation method of multidimensional coordinate measuring machine, calibration gage and fixture of calibration gage of multidimensional coordinate measuring machine |
| DE10222575A1 (en) * | 2002-05-17 | 2003-11-27 | Volkswagen Ag | DMIS compatibility test for coordinate measuring machines, uses standard test piece with alignment balls and range of standard geometric shapes |
| CN101526336A (en) * | 2009-04-20 | 2009-09-09 | 陈炳生 | Calibration method of linear structured light three-dimensional visual sensor based on measuring blocks |
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| Publication number | Publication date |
|---|---|
| ES2369802B1 (en) | 2012-06-26 |
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