Patent Publication Number: US-2015085273-A1

Title: Measurement support device, measurement supporting method, and computer program product

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2013-195736, filed on Sep. 20, 2013; the entire contents of which are incorporated herein by reference. 
     FIELD 
     An embodiment described herein relates generally to a measurement support device, a measurement supporting method, and a computer program product. 
     BACKGROUND 
     A measurement device that includes an image-capturing unit such as a camera and a measurement unit such as a laser range finder (LRF) calculates (produces) a three-dimensional model of an object by using a position of the object obtained from an image captured by the image-capturing unit, a distance to the object measured by the measurement unit, and calibration information obtained by calibrating the measurement unit and the image-capturing unit. 
     In the measurement device described above, the measurement unit needs to accurately measure the distance to the position of the object obtained from the image captured by the image-capturing unit in order to calculate an accurate three-dimensional model of the object. It is difficult, however, for the measurement unit to irradiate the exact position with laser. This may cause a difference between the actual distance and the measured distance to the position, thereby causing degradation in accuracy. 
     A conventional technology is known in which the image-capturing unit captures an image containing the measurement unit, the object, and an irradiated point of laser on the object emitted by the measurement unit, and the measurement device corrects the three-dimensional model (position coordinates of the three-dimensional model) of the object so that the objective function of the distance measured by the measurement unit and the distance between the image-capturing unit and the irradiated point in the image is minimized. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a configuration diagram illustrating an example of a measurement support device according to an embodiment; 
         FIG. 2  is a diagram illustrating an example of observation by a measurement unit and an image-capturing unit according to the embodiment; 
         FIG. 3  is a diagram illustrating an example of a method for dividing an image into regions according to the embodiment; 
         FIG. 4  is a diagram illustrating an example of an informing operation according to the embodiment; 
         FIG. 5  is a flowchart illustrating an example of processing performed by the measurement support device according to the embodiment; and 
         FIG. 6  is a block diagram illustrating an example of a hardware configuration of the measurement support device according to the embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     According to an embodiment, a measurement support device includes a measurement unit, an image-capturing unit, a first calculator, a second calculator, a determination unit, and an informing controller. The measurement unit is configured to sequentially irradiate an object with a light beam and sequentially measure a direction and a first distance to an irradiated point on the object. The image-capturing unit is configured to sequentially capture images of the object irradiated with the light beam. The first calculator is configured to calculate, when the direction and the first distance to the irradiated point are measured, a projection position on which the irradiated point is projected on each of the images by using the direction, the first distance, and calibration information that is based on calibration performed in advance between the measurement unit and the image-capturing unit. The second calculator is configured to calculate a set of reprojection positions by reprojecting, on each of the images, a three-dimensional position that is based on each of the images sequentially captured. The determination unit is configured to extract, from the set of reprojection positions, a reprojection position on an image containing the projection position calculated from the irradiated point that is measured and captured within a certain time period, calculate a second distance between the reprojection position and the projection position, and determine to which category the second distance belongs. The informing controller is configured to cause, when the determined category indicates continuation of measurement, an informing unit to inform of informing information that prompts to direct the measurement unit to irradiate the object with the light beam in a direction in which the second distance decreases. 
     An embodiment will be described in detail with reference to the accompanying drawings. 
       FIG. 1  is a configuration diagram illustrating an example of a measurement support device  10  according to the embodiment. As illustrated in  FIG. 1 , the measurement support device  10  includes a measurement unit  11 , an image-capturing unit  12 , a storage  13 , a first calculator  21 , a second calculator  22 , a selector  23 , a determination unit  24 , an informing controller  25 , and an informing unit  26 . 
     The measurement unit  11  can be implemented by a measurement device such as a LRF. Although the embodiment describes a case in which the measurement unit  11  is a LRF, the embodiment is not limited to this. The measurement unit  11  may be a device, such as a time-of-flight (ToF) camera using the phase shift method, that can acquire three-dimensional coordinates of an object. ToF is a method for measuring a distance from a time period required for a round-trip of laser emitted by the measurement unit to and from the object. The image-capturing unit  12  can be implemented by an image-capturing device such as an optical camera. 
     The storage  13  can be implemented by a storage device that can store therein data magnetically, optically, or electrically such as a hard disk drive (HDD), a solid state drive (SSD), a memory card, an optical disc, or a random access memory (RAM). 
     The first calculator  21 , the second calculator  22 , the selector  23 , the determination unit  24 , and the informing controller  25  can be implemented by causing a processor such as a central processing unit (CPU) to execute computer programs, that is, implemented by software. The informing unit  26  can be implemented by at least one of a display device such as a display, an audio output device such as a speaker, or a light-emitting device such as a lamp or a light-emitting diode (LED). 
     The measurement unit  11  sequentially irradiates an object with a light beam to sequentially measure a direction and a distance (a first distance) to an irradiated point on the object. The irradiated point is a position on the object on which the emitted light beam hits. 
     The measurement unit  11  may irradiate the object with a plurality of light beams at once. In this case, the measurement unit  11  irradiates the object with the light beams and measures directions and distances to the irradiated points on the object for the respective light beams. 
     The image-capturing unit  12  sequentially captures images of the object irradiated with a light beam by the measurement unit  11 . The image-capturing unit  12 , for example, captures visible light in space containing the object to obtain an image in which brightness of the object is recorded. 
     It is assumed that the measurement unit  11  and the image-capturing unit  12  are disposed in a fixed position so that an irradiated region with a light beam emitted by the measurement unit  11  and an image-capturing region of the image-capturing unit  12  overlap with each other. It is also assumed that the image-capturing unit  12  captures images of the object with the measurement unit  11  irradiating the object with a light beam. 
       FIG. 2  is a diagram illustrating an example of observation by the measurement unit  11  and the image-capturing unit  12  according to the present embodiment. As illustrated in  FIG. 2 , the measurement unit  11  irradiates an object  103  with a light beam  104 , and measures reflected light of the light beam  104  reflected on an irradiated point  105  to measure a direction and a distance to the irradiated point  105 . The image-capturing unit  12  captures an image  107  on which the object  103  is captured, and stores brightness of a captured subject such as the object  103  in the image  107 . 
     The measurement unit  11  and the image-capturing unit  12  may observe an object separately for a plurality of time periods, or may observe the object simultaneously for the time periods. Observing an object separately means that the measurement unit  11  and the image-capturing unit  12  are not synchronized with each other in observation, and observing an object simultaneously means that the measurement unit  11  and the image-capturing unit  12  are synchronized with each other in observation. 
     The storage  13  stores therein calibration information based on calibration performed in advance between the measurement unit  11  and the image-capturing unit  12 . The calibration information indicates at least one of the relative position and orientation of the measurement unit  11  and the image-capturing unit  12 . Examples of the calibration information include a geometric transformation parameter (Rrc, Trc) obtained by rotation and translation from a measurement coordinate system Or defined by the optical center and the direction of the optical axis of the measurement unit  11  to an image-capturing coordinate system Oc defined by the optical center and the direction of the optical axis of the image-capturing unit  12 . 
     When the measurement unit  11  measures a direction and a distance to an irradiated point, the first calculator  21  calculates a projection position on which the irradiated point is projected on an image by using the measured direction and distance and the calibration information stored in the storage  13 . The projection position may be hereinafter referred to as a projection point. 
     For example, the first calculator  21  calculates a projection point x on an image captured by the image-capturing unit  12  by using a three-dimensional position Xr of an irradiated point in the measurement coordinate system Or, calibration information (Rrc, Trc), a coefficient of a distortion model of the image-capturing unit  12 , and a projection function. 
     The three-dimensional position Xr is determined by the direction and the distance to the irradiated point measured by the measurement unit  11 . The coefficient of the distortion model is known by the image-capturing unit  12 . Examples of the coefficient of the distortion model include an intrinsic parameter matrix K and a lens distortion function that represent a focal length and the image center. Although, in the present embodiment, a distortion model represented by five parameters including three parameters of radial distortion and two parameters of tangential distortion is used as the lens distortion function, the embodiment is not limited to this. A more complex distortion model may be used in accordance with the lens model of the image-capturing unit  12 . The projection function can be defined by using, for example, the expression (16) described in Weng, J. and Cohen, P. and Herniou, M., “Camera calibration with distortion models and accuracy evaluation,” IEEE Transactions on pattern analysis and machine intelligence, volume 14, number 10, 1992, pp. 965-980. 
     When the measurement unit  11  irradiates the object with a plurality of light beams at once, the first calculator  21  calculates a plurality of projection positions on which a plurality of irradiated points are projected on an image. 
     The second calculator  22  reprojects a three-dimensional position based on each of the images sequentially captured by the image-capturing unit  12  on each of the images to calculate a set of reprojection positions. The reprojection position may be hereinafter referred to as a reprojection point. 
     The second calculator  22 , for example, uses simultaneous localization and mapping (SLAM) to calculate, from two or more time-series images captured by the image-capturing unit  12 , a viewpoint position and a view direction of the image-capturing unit  12 , and a three-dimensional position X_T observed at the time at which the image-capturing unit  12  captures each image. The second calculator  22  reprojects the three-dimensional position X_T on each of the images captured by the image-capturing unit  12  in the same manner as performed by the first calculator  21 . The second calculator  22  calculates a reprojection point on each image to calculate a set T of reprojection points. The second calculator  22  may exclude a reprojection point located outside of an image from the set T of reprojection points. “A reprojection point located outside of an image” means that the reprojection point is not captured in a subject image. This occurs when the three-dimensional position X_T is calculated by using a plurality of images and when the three-dimensional position X_T is captured in some images and is not captured in the other images. 
     When the image-capturing unit  12  captures a new image, the second calculator  22  recalculates (updates) the three-dimensional position X_T by using the new image in addition to the images already captured by the image-capturing unit  12 . The second calculator  22  reprojects the three-dimensional position X_T on each of the images captured by the image-capturing unit  12 , calculates a reprojection point on each of the images, and updates the set T of reprojection points. Such a recursive method for updating the set T of reprojection points is disclosed, for example, in B. D. Lucas and T. Kanade, “An Iterative Image Registration Technique with an Application to Stereo Vision,” in Proc. of Int. Joint Conf. on Artificial Intelligence, pp. 674-679, August 1981. 
     As described above, the three-dimensional position X_T and the set T of reprojection points change in value as time proceeds. When the second calculator  22  performs processing by using the three-dimensional position X_T or the set T of reprojection points, the second calculator  22  uses the latest three-dimensional position X_T or the latest set T of reprojection points. The method for updating the three-dimensional position X_T and the set T of reprojection points, however, is not limited to this. The second calculator  22  may associate a past three-dimensional position X_T with a past set T of reprojection points and store them in, for example, the storage  13  when updating the three-dimensional position X_T and the set T of reprojection points. This enables the second calculator  22  to perform processing by using the past three-dimensional position X_T and the past set T of reprojection points. 
     When the second calculator  22  calculates a plurality of three-dimensional positions X_T, the second calculator  22  reprojects the three-dimensional positions X_T on each image to calculate a plurality of sets T of reprojection positions. 
     The selector  23  selects, from a plurality of sets T of reprojection positions, candidate positions that are reprojection positions obtained by reprojecting three-dimensional positions with higher measurement accuracy to acquire a set TC of candidate positions. A candidate position may be hereinafter referred to as a candidate point. A three-dimensional position with higher measurement accuracy is, for example, a three-dimensional position measured by the image-capturing unit  12  or a three-dimensional position measured by the measurement unit  11  that has higher measurement accuracy than a certain value. 
     The selector  23  defines, as Length_num (T, t), the number of reprojection points in a set T of reprojection points from the most previous time to time t, and defines, as Length_time (T, t), a time period from the most previous time to time t in the set T of reprojection points. 
     The selector  23  estimates, from an image captured at time t, a specular reflection rate Ref_rate (X_T, t) and a diffuse reflection rate Dif_rate (X_T, t) of the three-dimensional position X_T. To estimate the specular reflection rate Ref_rate (X_T, t) and the diffuse reflection rate Dif_rate (X_T, t), the selector  23  can employ a method disclosed, for example, in Tomoaki Higo, Daisuke Miyazaki, Katsushi Ikeuchi, “Realtime Removal of Specular Reflection Component Based on Dichromatic Reflection Model (General Session 5),” Information Processing Society of Japan, Computer Vision and Image Media (CVIM), Volume 93, 2006, pp. 211-218, Sep. 8, 2006. 
     The selector  23  uses a viewpoint position (calculated by SLAM) of the image-capturing unit  12  at time t to calculate a relative distance Rel_dis (X_T, t) (a third distance) from the image-capturing unit  12  to the three-dimensional point X_T at time t. The three-dimensional point X_T and the viewpoint position and the view direction of the image-capturing unit  12  at time t are represented in a coordinate system with the origin being at the position of the image-capturing unit  12  at image-capturing time of an image on which SLAM was started. The coordinate system is represented in an uncertain reduction scale. An image on which SLAM is started is, for example, an image first given when the set T of reprojection points is calculated. 
     The selector  23  calculates a prediction error Rel_err (X_T, t) in the relative distance Rel_dis (X_T, t) of the image-capturing unit  12  relative to the object by using two sets of a viewpoint position and a view direction of the image-capturing unit  12 , the pixel size of optical elements in the image-capturing unit  12 , and an intrinsic parameter of the image-capturing unit  12 . To calculate the prediction error Rel_err (X_T, t), the selector  23  may employ a method disclosed, for example, in J. J. Rodriguez and J. K. Aggarwal, “Stochastic analysis of stereo quantization error,” IEEE Transactions on Pattern Analysis and Machine Intelligence, 12:467-470, 1990. For example, the selector  23  may use, as the two sets of a viewpoint position and a view direction of the image-capturing unit  12 , viewpoint positions and view directions of the image-capturing unit  12  at the most previous time in the elements of the set T of reprojection points and at time t. 
     From sets of three-dimensional points {X_Tj} corresponding to a plurality of sets of reprojection positions {Tj} (j=1, 2, . . . , M) calculated by the second calculator  22 , the selector  23  selects, as candidate points, {Tj} corresponding to {X_Tj} satisfying, for example, the following conditions: Length_num (T, t) is larger than a certain value α1, Length_time (T, t) is larger than a certain value α2, Ref_rate (X_T, t) is smaller than a certain value α3, Dif_rate (X_T, t) is larger than a certain value α4, Rel_dis (X_Tj, t) is smaller than a certain value β1 and is the minimum, and Rel_err (X_Tj, t) is smaller than a certain value β2 and is the minimum. The selector  23  thus acquires a set TC of candidate points. 
     Specifically, the selector  23  sets a measurement recommendation flag G of {Tj} corresponding to {X_Tj} that satisfies the above-described conditions to 1, and sets the measurement recommendation flag G of {Tj} corresponding to {X_Tj} that does not satisfy the above-described conditions to 0, thereby acquiring the set TC of candidate points. The measurement recommendation flag G is a flag indicating whether a candidate point (reprojection point) is suitable for measurement. When the measurement recommendation flag G is 1, the candidate point is suitable for measurement. When it is 0, the candidate point is not suitable for measurement. The initial value of the measurement recommendation flag G is 0. The value of the measurement recommendation flag G is inherited even when the set T of reprojection points is updated by the second calculator  22  and when the set TC of candidate points is updated. 
     Although, in the present embodiment, it is assumed to select a reprojection point that satisfies all the conditions described above as a candidate point, the embodiment is not limited to this. A reprojection point that satisfies at least one of the conditions may be selected as a candidate point. Although the above-described conditions specify that Rel_dis (X_Tj, t) and Rel_err (X_Tj, t) are the minimum, the embodiment is not limited to this. The conditions may specify that Rel_dis (X_Tj, t) and Rel_err (X_Tj, t) are among the first certain number of values when sorted in ascending order. 
     The determination unit  24  extracts, from the set of reprojection positions calculated by the second calculator  22 , a reprojection position on an image containing a projection position calculated from an irradiated point measured and captured within a certain time period. The determination unit  24  calculates a distance (a second distance) between the reprojection position and the projection position and determines to which category the distance belongs. 
     When the second calculator  22  calculates a plurality of sets T of reprojection positions, the determination unit  24  extracts, from the sets T of reprojection positions, a plurality of reprojection positions on an image containing a projection position calculated from an irradiated point measured and captured within a certain time period. The determination unit  24  calculates the minimum distance among distances between the reprojection positions and the projection position and determines to which category the minimum distance belongs. 
     The determination unit  24  may extract, from the sets T of reprojection positions, one or more reprojection positions contained in a region containing a larger number of reprojection positions among the reprojection positions on an image containing a projection position calculated from an irradiated point measured and captured within a certain time period. 
     In practice, the determination unit  24  extracts, from the set TC of candidate positions selected by the selector  23 , a candidate position on an image containing a projection position calculated from an irradiated point measured and captured within a certain time period. The determination unit  24  then calculates a distance between the candidate position and the projection position. 
     When the measurement unit  11  irradiates the object with a plurality of light beams, the determination unit  24  extracts, from a set T of reprojection positions, a reprojection position on an image containing a plurality of projection positions calculated from a plurality of irradiated points measured and captured within a certain time period. The determination unit  24  calculates the minimum distance among distances between the projection positions and the reprojection position and determines to which category the minimum distance belongs. 
     It is assumed, in the present embodiment, that “measured and captured within a certain time period” means that measuring time and image-capturing time coincide with each other, but the embodiment is not limited to this. Some errors may be tolerable between the measuring time and the image-capturing time. 
     When the calculated distance is larger than a threshold, the determination unit  24  determines that the distance belongs to a category indicating continuation of measurement. When the calculated distance is equal to or smaller than the threshold, the determination unit  24  determines that the distance belongs to a category indicating completion of measurement. 
     The following describes detailed processing performed by the determination unit  24 . 
     First, the determination unit  24  extracts a set Cand of candidate points at time t from a set TC of candidate points selected by the selector  23 . The determination unit  24  divides an image at time t into a plurality of regions, counts the number of candidate points belonging to the set Cand in each region, and uses a candidate point belonging to a region that contains the largest number of candidate points to determine a measurement situation. 
       FIG. 3  is a diagram illustrating an example of a method for dividing an image into regions according to the present embodiment. In the example illustrated in  FIG. 3 , the determination unit  24  calculates a center-of-gravity point  41  from candidate points  40  on an image  46  and performs the principal component analysis to calculate a principal component direction  42 . The determination unit  24  considers a line  43  extending in the principal component direction  42  to divide the image  46  into two regions  44  and  45 . The determination unit  24  uses candidate points  40  belonging to the region  44  containing a larger number of candidate points  40  to determine the measurement situation. 
     The determination unit  24  calculates combinations of respective projection points xp belonging to a set Proj of projection points and candidate points xc belonging to the region containing the largest number of candidate points such that the distance between a projection point xp and a candidate point xc is the shortest, and calculates combinations of respective candidate points xc belonging to the region and projection points xp belonging to the set Proj such that the distance between a candidate point xc and a projection point xp is the shortest. The determination unit  24  thus obtains a set P of combinations. 
     The determination unit  24  calculates a distance D for each combination. If the distance D is equal to or smaller than a certain value γ1, the determination unit  24  updates a measured flag F of a candidate point of each combination to 1. Although, in the present embodiment, the certain value γ1 is assumed to be 1% of the height or the width of the image, the embodiment is not limited to this. The measured flag F is a flag indicating whether a three-dimensional point X_T corresponding to a candidate point (reprojection point) has successfully been measured. When the measured flag F is 1, the three-dimensional point X_T has successfully been measured. When it is 0, the three-dimensional point X_T has not been successfully measured. The initial value of the measured flag F is 0. The value of the measured flag F is inherited even when the set T of reprojection points is updated by the second calculator  22  and when the set TC of candidate points is updated. 
     The determination unit  24  determines that, when the distance D of each combination is equal to or smaller than the certain value γ1, the combination belongs to a first category, when the distance D is larger than the certain value γ1 and equal to or smaller than a certain value γ2, the combination belongs to a second category, and when the distance D is larger than the certain value γ2, the combination belongs to a third category. Although the certain value γ2 may be determined, for example, to be 5% of the height or the width of the image, the embodiment is not limited to this. The number of categories is not limited to three, but may be set to any number. 
     The determination unit  24  determines whether to complete measurement. For example, if the number of elements in the set TC with the measured flag F being 1 is larger than a certain value Φ1, the determination unit  24  determines to complete measurement. 
     When a determined category indicates continuation of measurement, the informing controller  25  causes the informing unit  26  to inform a measurer of informing information that prompts the measurer to direct the measurement unit  11  to irradiate the object with a light beam in a direction in which the distance decreases. When a determined category indicates completion of measurement, the informing controller  25  causes the informing unit  26  to inform the measurer of informing information indicating that the measurement on an extracted reprojection position is completed. The informing controller  25  causes the informing unit  26  to perform an informing operation by at least one of the following: by outputting images, outputting sounds, outputting light, and by vibration. 
       FIG. 4  is a diagram illustrating an example of an informing operation according to the present embodiment. As illustrated in  FIG. 4 , projection points  34  contained in the set Proj and candidate points  33  contained in the set Cand are discretized into integer values and illustrated on an image  30  containing objects  36 , thereby obtaining a measurement instruction image  37 . It is preferable that the color of candidate points  33  and that of the projection points  34  are different from each other. It is preferable that a candidate point  33  is illustrated in a different color dependent on whether the value of the corresponding measured flag is 1 or 0, or it is preferable that a candidate point  33  with a measured flag having a value of 1 is not illustrated on the image. The informing controller  25  illustrates an arrow  35  connecting a combination of a projection point  34  and a candidate point  33  on the measurement instruction image  37 . 
     In the example illustrated in  FIG. 4 , the informing controller  25  displays a different sentence on the measurement instruction image  37  depending on the categories so that the measurer is informed of a category determined by using the distance D. The example of  FIG. 4  illustrates a case of the second category (continuation of measurement), and a sentence “move slowly to bring closer” is displayed as a sentence  32 . In a case of the third category (continuation of measurement), a sentence “bring closer” is displayed as the sentence  32 . In a case of the first category (completion of measurement), a sentence “successfully measured” is displayed as the sentence  32 . 
     The informing controller  25  may inform the measurer of information such that, in the first category, the measurer is informed that the measurement has been successfully performed, and in the second or the third category, the measurer is prompted to move the measurement unit  11  more slowly as the category is closer to the first category. The method for informing the measurer is not limited to displaying the sentence  32 . The informing controller  25  may inform the measurer of such information by outputting a beep, instead of displaying a sentence, at regular intervals, and as the category is closer to the first category, the volume of the beep increases or the beep is output at shorter intervals. The informing controller  25  may inform the measurer of the information such that the arrow  35  is illustrated in certain colors depending on the categories. The informing controller  25  may inform the measurer of the information by installing a lighting device such as an LED in advance in the measurement support device to emit light in different colors depending on the categories. 
       FIG. 5  is a flowchart illustrating an example of the procedure performed by the measurement support device  10  according to the present embodiment. 
     First, the measurement unit  11  measures an object, and the image-capturing unit  12  captures images of the object (Step S 101  and S 103 ). 
     The first calculator  21  calculates the set Proj of projection points (Step S 105 ). 
     The second calculator  22  calculates the set T of reprojection points (Step S 107 ). 
     The selector  23  selects the set TC of candidate points from the set T of reprojection points (Step S 109 ). 
     The determination unit  24  extracts the set Cand at time t from the set TC of candidate points and calculates combinations of the respective projection points xp belonging to the set Proj of projection points and candidate points xc belonging to the set Cand such that the distance between a projection point xp and a candidate point xc is the shortest, and also calculates combinations of respective candidate points xc belonging to the set Cand and projection points xp belonging to the set Proj such that the distance between a candidate point xc and a projection point xp is the shortest, so that the determination unit  24  calculates the set P of combinations to determine a measurement situation (Step Sill). 
     The determination unit  24  calculates the distance D for each combination and determines to which category the distance D belongs and a completion condition as the measurement situation (Step S 112 ). 
     If the completion condition is satisfied, the determination unit  24  ends the measurement (Yes at Step S 113 ). 
     If the completion condition is not satisfied, the informing controller  25  informs the measurer of information (measurement support information) depending on a category (Step S 115 ), and the processing returns to Step S 103 . 
     According to the embodiment described above, the measurement support device informs the measurer of a position of an object acquired from an image captured by the image-capturing unit so that the measurer is prompted to move the measurement unit to irradiate the position with a light beam. This enables the measurer to accurately measure the distance to the position, whereby the measurement support device can accurately calculate the reduced scale of a three-dimensional model of the object, and can contribute to producing an accurate three-dimensional model of the object. 
     According to the present embodiment, there is no restriction, for example, on an arrangement of a measurement device, thereby easily contributing to producing an accurate three-dimensional model of the object. 
     Hardware Configuration 
       FIG. 6  is a block diagram illustrating an example of a hardware configuration of the measurement support device  10  according to the present embodiment. As illustrated in  FIG. 6 , the measurement support device  10  according to the present embodiment includes a control device  91  such as a central processing unit (CPU), a storage device  92  such as a read only memory (ROM) and a random access memory (RAM), an external storage device  93  such as a hard disk drive (HDD) and a solid state drive (SSD), a display device  94  such as a display, an input device  95  such as a mouse and a keyboard, a communication I/F  96 , a measurement device  97  such as a laser sensor, and an image-capturing device  98  such as a digital camera, and can be implemented by a hardware configuration using a typical computer. 
     A computer program executed in the measurement support device  10  according to the present embodiment is embedded and provided in a ROM, for example. The computer program executed in the measurement support device  10  according to the present embodiment is recorded and provided, as a computer program product, in a computer-readable recording medium such as a compact disc read only memory (CD-ROM), a compact disc recordable (CD-R), a memory card, a digital versatile disc (DVD), and a flexible disk (FD) as an installable or executable file. The computer program executed in the measurement support device  10  according to the present embodiment may be stored in a computer connected to a network such as the Internet and provided by being downloaded via the network. 
     The computer program executed in the measurement support device  10  according to the present embodiment has a module configuration that implements the units described above on the computer. As hardware, the control device  91  loads the computer program from the external storage device  93  on the storage device  92  and executes it, thereby implementing the above-described units on the computer. 
     As described above, the measurement support device according to the present embodiment can contribute to producing an accurate three-dimensional model of an object. 
     In the embodiment above, for example, the steps of the flowcharts may be performed in a different order, a plurality of steps may be performed simultaneously, or the steps may be performed in a different order for each round of the process, as long as these changes are not inconsistent with the nature of the steps. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.