Surveying system

Abstract

The objective of the present invention is to provide a relatively inexpensive surveying system having an automatic turning function. A surveying system (1) comprises a distance measuring instrument (11) that is accommodated in a telescope (6c) and that measures the distance to a prism (8), an angle detector (12) that has an angle of view wider than the viewing angle of the telescope (6c) and that detects the angle of a collimation optical axis A of the telescope (6c), a rotational drive unit (13) that rotationally drives the telescope (6c), a camera that acquires an image in front of the telescope, and a control and computing unit (30), wherein a rough target (RT) for performing a rough turn prior to collimation of the prism (8) is set, and the control and computing unit (30) is configured to: detect the position of the rough target (RT) from the image (70); calculate a rough rotation angle θt for turning the collimation optical axis of the telescope (6c) roughly in the direction of the rough target (RT) on the basis of the position of the rough target (RT) in the image (70); set a rough target of interest (RTt) to be turned to, from the rough target (RT) in the image (70); and drive the rotational drive unit so as to rotate the telescope (6c) through the rough rotation angle θt.

Description

Surveying System

[0001] The present disclosure relates to a surveying system, and more particularly to a surveying system having an automatic turning function that automatically rotates in a prism direction.

[0002] Conventionally, a technology has been proposed that realizes an automatic turning function that detects the direction of a prism and automatically rotates the telescope in the direction of the prism so that the surveying instrument can collimate the prism when starting a measurement or when automatic tracking has failed, etc. Patent Document 1 discloses a technology in which an operator holding a prism uses an optical transmitter called a remote catcher to transmit a fan beam, which is received by an optical receiver provided in the surveying instrument, and the surveying instrument is rotated in the direction of the incoming light to lock the prism.

[0003] Furthermore, Patent Document 2 discloses a technique for locking a prism by moving the telescope in a spiral pattern from the center outward to search for the prism so that it is within the field of view of the telescope.

[0004] JP 2005-214854 A JP 2016-138802 A

[0005] Furthermore, Japanese Patent Application No. 2022-157179 proposes a technology in which a GNSS receiver is used to obtain the approximate position of a prism, and a surveying instrument is rotated in the direction of the prism based on the position information of the GNSS receiver.

[0006] However, the technology of Patent Document 2 has the problem of taking a long time to search for the prism. Furthermore, the technologies disclosed in Patent Document 1 and Patent Application No. 2022-157179 require additional hardware, such as software, a device for transmitting and receiving the fan beam, a GNSS receiver, and communication equipment, resulting in high implementation costs. Meanwhile, in recent years, there has been an increasing trend toward cameras being installed in surveying instruments. For this reason, there has been a demand for a surveying instrument that uses a camera and has an automatic turning function at a relatively low cost.

[0007] The present invention has been made in view of the above circumstances, and has as its object to provide a surveying system that is relatively inexpensive and has an automatic turning-around function.

[0008] In order to achieve the above object, a surveying system according to one aspect of the present invention has the following configuration.

[0009] 1. A surveying system comprising: a distance measuring device housed in a telescope, which sends distance measuring light to a prism and receives the reflected light from the prism to measure the distance to the center of the prism; an angle detector which detects the angle of the collimation optical axis of the telescope; a rotary drive unit which drives the telescope in rotation; a camera which has a field of view wider than the field of view of the telescope and captures an image in front of the telescope; and a control and calculation unit which has at least one electronic circuit and at least one memory; wherein a general target for roughly turning the prism is set, and the control and calculation unit is configured to detect the general target from the image, calculate a general rotation angle for roughly turning the collimation optical axis of the telescope toward the general target based on the position of the general target, set a target general target to be turned from the general target in the image, and drive the rotary drive unit to rotate the telescope by the general rotation angle.

[0010] 2. In the above aspect 1, it is also preferable that the outline targets include a first outline target and a second outline target having dimensions larger than the first outline target, and the target outline target is set according to an approximate distance to the first outline target and an approximate distance to the second outline target.

[0011] 3. In the above aspects 1 and 2, it is also preferable that the first outline target is the prism, and the second outline target is clothing worn by a worker holding the prism.

[0012] 4. In the above aspects 1 to 3, it is also preferable that the rough target is the prism.

[0013] 5. In the above aspects 1 to 4, it is also preferable that the camera is provided inside the telescope so that its optical axis is coaxial with the collimation optical axis of the telescope.

[0014] 6. In the above aspects 1 to 5, it is also preferable that the camera is provided at a distance from the telescope, the relationship between the position and direction of the camera and the telescope is known, and the control and calculation unit calculates the approximate distance to the approximate target based on the size of the approximate target in the image.

[0015] 7. In the above aspects 1 to 6, it is also preferable that the control and calculation unit detects the outline target from an input image by applying an object detection model that detects the outline target from the image through machine learning.

[0016] 8. In the above aspects 1 to 7, it is also preferable that the control and calculation unit controls the rotation drive unit and the camera to obtain a panoramic image in front of the telescope, and detect the approximate target from the panoramic image.

[0017] According to the above configuration, it is possible to provide a surveying system equipped with an automatic turning-around function at a relatively low cost.

[0018] FIG. 1 is a schematic external view showing the usage state of a surveying system according to a first embodiment of the present invention. FIG. 1 is a configuration block diagram of the surveying system. FIG. 2 is a flowchart showing an example of a general process of a look-around function by the surveying system. FIG. 3 is an image diagram explaining an overview of the look-around function by the surveying system. FIG. 4 is a flowchart showing a detailed process of calculating an approximate rotation angle in the processing of the look-around function. FIG. 5 is a diagram explaining a method of calculating the center position of a rough target for calculating the rough rotation angle. FIG. 6 is a diagram explaining a method of calculating a horizontal approximate rotation angle for calculating the rough rotation angle. FIG. 7 is a flowchart showing a detailed process of setting a look-around target rough target in the processing of the look-around function. FIG. 8 is a flowchart showing a process of setting a target rough target when one type of rough target is used in the surveying system. FIG. 9 is a configuration block diagram of a surveying system according to a second embodiment. FIG. 10 is a configuration block diagram of a surveying system according to a modification of the first embodiment. FIG. 11 is an example of an image based on reference data according to another modification of the surveying system according to the first embodiment. FIG. 12 is another example of an image based on reference data of the surveying system. FIG. 13 is a diagram explaining a panoramic image acquired by a camera provided in a surveying system according to yet another modification of the above embodiment. FIG. 14 is a flowchart showing an example of a general process of the look-around function of the surveying system.

[0019] A preferred embodiment of the present invention will be described with reference to the drawings. In the following description of the embodiment, the same components are given the same reference numerals, and the same functions are given the same names, and redundant description will be omitted as appropriate.

[0020] 1. First Embodiment (Outline of Surveying System 1) Fig. 1 is a schematic diagram of a surveying system 1 according to a first embodiment in use. The surveying system 1 includes a surveying instrument 10 and a data processing device 50.

[0021] The surveying instrument 10 is a total station that, from below, has a leveling unit 4, a base unit 6a mounted on the leveling unit 4, a support unit 6b that rotates horizontally on the base unit 6a, and a telescope 6c that rotates vertically at the center of the support unit 6b. A camera 14 is attached to the top of the housing of the telescope 6c and rotates integrally with the telescope 6c. The optical axis B of the camera 14 is aligned horizontally with the collimation optical axis A of the telescope 6c and is parallel to it in the vertical plane. The surveying instrument 10 is mounted on a tripod 2 at a known point P. The data processing device 50 is a computer configured to be able to communicate with the surveying instrument 10.

[0022] The worker OP carries the pole 9 with the prism 8 attached to it to the measurement point Q. At the measurement point Q, the worker OP holds the pole 9 vertically facing the surveying instrument 10, and causes the surveying instrument 10 to automatically collimate the prism 8, which then measures the distance to the center O of the prism 8. At this time, it is preferable to hold the prism 8 so that the relative positional relationship between the prism 8 and the jacket 7 of the worker OP is roughly constant. As shown in the figure, it is particularly preferable to hold the prism 8 near the center of the jacket 7 of the worker OP.

[0023] In order to capture the prism 8 within or near the narrow field of view of the telescope 6c, the surveying system 1 is preset with a general target RT for general turning. The surveying system 1 acquires a wide-angle image (hereinafter simply referred to as an image; in this specification, wide-angle means a field angle wider than the telescope's field of view) 70 in front of the telescope 6c using the camera 14, and detects the general target RT. The surveying system 1 then calculates a general rotation angle θt for directing the telescope 6c toward the general target RT, and rotates the telescope 6c by the general rotation angle θt to capture the prism 8 within the field of view. Then, precise automatic collimation is performed.

[0024] (Outline Target) The outline target RT is a target for outline turning rotation (hereinafter referred to as outline rotation) to roughly point the telescope 6c toward the prism 8, which is the final target, in order to precisely and automatically aim at the prism 8. In the surveying system 1, the prism 8 is set as the first outline target RT1, and the jacket (clothing) 7 of the operator OP is set as the second outline target RT2.

[0025] Generally, the prism 8 has a length and width of approximately 10 cm by approximately 10 cm (depending on the type), while the jacket of the worker OP has a length and width of approximately 50 cm by approximately 60 cm. In other words, the second outline target RT2 is larger in size than the first outline target RT1. The second outline target RT2 is not limited to the jacket 7 of the worker OP, but may also be a suit including a jacket and pants, or a safety reflective vest. Furthermore, it is preferable to use a dedicated jacket with a unified size, design, and color scheme for the jacket 7.

[0026] (Details of Surveying System 1) Figure 2 is a block diagram of the surveying system 1. As shown in Figure 2, the surveying instrument 10 includes a distance measuring device 11, an angle detector 12, a rotation drive unit 13, a camera 14, an automatic collimation unit 15, a memory unit 16, an input unit 17, a display unit 18, a communication unit 19, and a surveying instrument calculation unit 20. The angle detector 12 includes a horizontal angle detector 12a and a vertical angle detector 12b. The rotation drive unit 13 includes a horizontal rotation drive unit 13a and a vertical rotation drive unit 13b.

[0027] The horizontal rotation drive unit 13a and horizontal angle detector 12a are housed in the base unit 6a. The vertical rotation drive unit 13b, vertical angle detector 12b, memory unit 16, and surveying instrument calculation unit 20 are housed in the base unit 6b. The input unit 17 and display unit 18 are provided outside the base unit 6b. The distance measuring device 11 and automatic collimation unit 15 are housed in the telescope 6c, and the camera 14 is attached to the top of the telescope 6c as described above.

[0028] The distance measuring instrument 11 is an optical distance meter equipped with a light-transmitting unit having a light-emitting element such as a laser diode, a distance measuring optical system, a reference optical path, and a light-receiving unit having a light-receiving element such as an avalanche photodiode. The distance measuring instrument 11 emits distance measuring light such as infrared laser light via the distance measuring optical system to the prism 8 along the collimation optical axis A of the telescope 6c, and receives the reflected light at the light-receiving unit. The distance measuring instrument 11 then outputs light-receiving signals of the distance measuring light and the internal reference light that enters the light-receiving element via the reference optical path to the surveying instrument computing unit 20. The surveying instrument computing unit 20 calculates the distance to the center of the prism 8 from the phase difference or time difference between the distance measuring light and the internal reference light.

[0029] The horizontal angle detector 12a and the vertical angle detector 12b are rotary encoders that detect the rotation angles of the base unit 6b and the telescope 6c around their rotation axes, which are driven by the horizontal rotation drive unit 13a and the vertical rotation drive unit 13b, respectively. The surveying instrument calculation unit 20 calculates the horizontal angle and the vertical angle of the collimation optical axis A of the telescope 6c based on the detection signals.

[0030] The horizontal rotation drive unit 13a and the vertical rotation drive unit 13b are motors. The horizontal rotation drive unit 13a rotates the base unit 6b horizontally around the axis H-H under the control of the surveying instrument calculation unit 20. The vertical rotation drive unit 13b also rotates the telescope 6c vertically around the axis V-V under the control of the surveying instrument calculation unit 20.

[0031] The camera 14 is an RGB camera equipped with an objective lens and an image sensor such as a CCD (Charge-Coupled Device) or CMOS (Complementary Metal-Oxide-Semiconductor) sensor, and captures color images of the area in front of the telescope 6c. The image sensor has a Cartesian coordinate system with the camera center as its origin, and the local coordinates of each pixel are identified. The positional relationship between the camera center and the instrument center of the surveying instrument 10 is known, and the control and calculation unit 30 can convert and manage images captured by the camera 14 into the coordinates of the surveying instrument 10. The camera 14 has a wider angle of view than the telescope 6c. Specifically, while the telescope has an angle of view of 1.5° x 1.5° (vertical x horizontal), the camera 14 has an angle of view of, but not limited to, approximately 10° x approximately 15° (vertical x horizontal). The image sensor has a Cartesian coordinate system with the camera center as its origin, and the position of each pixel on the imaging surface can be identified. The positional relationship between the center of the camera, the instrument center of the surveying instrument 10, and the collimation optical axis A is known. The optical axis of the camera 14 coincides with the collimation optical axis A of the telescope 6c in the horizontal direction, and the horizontal angle of view with respect to the collimation optical axis A of the telescope 6c (the angle with respect to the optical axis obtained from the pixel position) can be obtained by determining the position of the pixel on the image sensor.

[0032] The automatic collimation unit 15 includes a collimation light transmitting unit with a light-emitting element such as a laser diode, a collimation optical system with a lens and a dichroic prism, and a collimation light receiving unit with an image sensor such as a CCD or CMOS sensor (not shown). The automatic collimation unit 15 emits collimation light of a different wavelength from the distance measurement light along a common optical axis, receives the reflected light with the image sensor, and captures landscape images in the collimation direction when the collimation light is on and when the collimation light is off. Both images are output to the surveying instrument calculation unit 20. The image sensor is configured to identify the position of pixels on the light-receiving surface (image capture surface). Furthermore, the center of the image sensor is aligned with the optical axis of the distance measurement light. By determining the position of the pixels on the image sensor, the angle of view relative to the optical axis of the distance measurement light (the angle relative to the optical axis obtained from the pixel position) can be calculated. The surveying instrument calculation unit 20 calculates the center of the image of the prism 8 from the difference between the two images, and drives the rotation drive unit 13 based on the result of the position detection of the prism 8 to collimate the center O of the prism 8.

[0033] The storage unit 16 is a computer-readable storage medium such as a hard disk drive (HDD), a solid state drive (SSD), a flash memory, etc. The storage unit 16 stores programs and related data for executing various functions of the surveying instrument 10, including the prism turning function. The storage unit 16 also stores data for identifying the outline target RT to be detected as reference data, which will be described later.

[0034] The input unit 17 is an operation button. The operator OP inputs commands for causing the surveying instrument 10 to perform operations and selects settings via the input unit 17.

[0035] The display unit 18 is, for example, a liquid crystal display or an organic EL display, and displays various information such as measurement results and calculation results under the control of the surveying instrument calculation unit 20. The input unit 17 and the display unit 18 may be integrated into one unit to form a touch panel display.

[0036] The communication unit 19 is a communication interface that enables wired or wireless communication with the data processing device 50. The surveying instrument 10 and the data processing device 50 may be able to communicate with each other via short-range wireless communication such as Wi-Fi or Bluetooth, or may be able to communicate with each other via a communication network such as the Internet.

[0037] The surveying instrument calculation unit 20 includes at least one electronic circuit and at least one memory. For example, a processor such as a CPU (Central Processing Unit) is used as the electronic circuit. For example, a static random access memory (SRAM) or a dynamic random access memory (DRAM) is used as the memory. When a CPU is used, the control calculation unit 30 executes various functions of the surveying instrument 10 by reading programs for the CPU to execute functions into the memory and executing them.

[0038] The surveying instrument calculation unit 20 may be partially configured as hardware using a CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array), or the like.

[0039] The surveying instrument calculation unit 20 is connected to the distance measuring device 11, angle detector 12, rotation drive unit 13, camera 14, automatic collimation unit 15, memory unit 16, input unit 17, display unit 18 and communication unit 19, and performs the control necessary to execute the functions of the surveying instrument 10 and inputs and outputs information.

[0040] The surveying instrument calculation unit 20 includes, as functional units, a wide-angle image acquisition unit 21, a rough rotation execution unit 22, and a precision collimation execution unit 23.

[0041] The wide-angle image acquisition unit 21 controls the camera 14 to acquire an image 70 of the area in front of the telescope 6c. The approximate rotation execution unit 22 drives the rotation drive unit 13 to rotate the telescope 6c by the rotation angle calculated by the approximate rotation angle calculation unit (described later). The precise collimation execution unit 23 drives the automatic collimation unit 15 to precisely collimate the prism 8 that has entered the field of view of the telescope 6c due to the approximate rotation.

[0042] The data processing device 50 is a computer configured to be able to communicate with the surveying instrument 10, and includes a processing device calculation unit 60, a storage unit 51, and a communication unit 52. In the illustrated example, it is shown as a personal computer that also includes an input unit such as a keyboard and a display unit that is a liquid crystal display. However, it is not limited to this and may also be a server computer, a cloud computer, or the like.

[0043] The processing device calculation unit 60 includes at least one electronic circuit and at least one memory. For example, a processor such as a CPU is used as the electronic circuit. For example, an SRAM, a DRAM, or the like is used as the memory. When a CPU is used, the control calculation unit 30 executes various functions of the data processing device 50 by having the CPU load a program for executing the functions of the data processing device 50 into the memory and execute the program. A part of the processing device calculation unit 60 may be configured as hardware using a CPLD, FPGA, or the like.

[0044] The processing device calculation unit 60 includes, as functional units, a general target detection unit 61, a general rotation angle calculation unit 62, and a general target identification unit 63. The general target detection unit 61 detects a general target from the image 70. The general rotation angle calculation unit 62 calculates the angle between the center of the detected general target and the direction of the collimation optical axis A as the general rotation angle. The general target identification unit 63 sets a general target RT to turn towards from the detected general target RT. The detailed operation of each unit will be described later.

[0045] The storage unit 51 is a computer-readable storage medium such as an HDD, a solid-state drive (SSD), or a flash memory. It stores programs and related data for executing the above-mentioned functional units. The storage unit 51 also stores, as reference data 80, images of the outline targets RT to be detected by the outline target detection unit 61. The detailed operation of each unit will be described later.

[0046] The communication unit 52 is a communication interface similar to the communication unit 19, and enables wired or wireless communication with the surveying instrument 10.

[0047] (Overall Processing of Turn-Around Function) Next, the overall processing flow when the turn-around function is executed will be described with reference to Fig. 3. In this embodiment, the turn-around function is realized by the surveying instrument calculation unit 20 and the processing device calculation unit 60 working together to function as the control calculation unit 30 of the surveying system 1.

[0048] When the turning-around function is started, in step S01, the wide-angle image acquisition unit 21 controls the camera 14 to acquire an image 70 of the area in front of the telescope 6c. FIG. 4A shows an example of the image 70. The image 70 in FIG. 4A includes the operator OP holding the prism 8, as well as the prism 8 (which may be installed on a stand, for example). The wide-angle image acquisition unit 21 outputs the acquired image 70 to the processing device calculation unit 60 of the data processing device 50.

[0049] Next, in step S02, the general target detection unit 61 detects whether a general target RT is present in the image 70, and if so, detects its position and range. The detection of the general target RT can be performed using an object detection model based on machine learning using R-CNN (Region Based Convolutional Neural Network), Fast R-CNN, Mask R-CNN, YOLO, or segmentation. Various object detection models are known, and an appropriate model can be selected from these models taking into account the required computational resources and data set. The object detection model is constructed as a model that detects an object from an input image by referencing reference data registered to detect a general target according to the model, and outputs the object's position and range.

[0050] For example, a case will be described in which a segmentation model is used to divide each pixel in an image into segments of the object to which each pixel belongs. In this case, the average value (reference feature) of the feature of the general target RT (prism 8 and jacket 7) calculated based on an image of the general target RT is stored in the storage unit 51 as reference data. The image 70 is then segmented using the segmentation model, the feature of each pixel is compared with the reference feature, and the segment containing the most similar pixel is detected as the general target. A segment anything model can be used as the segmentation model for this purpose.

[0051] Alternatively, the object detection model is not limited to machine learning, and may be realized by a known pattern matching technique using image data of the prism 8 and the jacket 7 as a pattern template. Fig. 4B shows a state in which the outline target RT is detected in step S02. In this case, a pattern template based on the image of the outline target RT (prism 8 and jacket 7) is stored in the storage unit 51 as reference data.

[0052] When the general target RT is detected, a bounding box is set around the detected general target RT as shown by the dashed line.

[0053] Next, in step S03, the outline target detection unit 61 determines whether the detection of the outline target RT was successful. This is because the outline target RT may not be detected in the image 70 depending on the distance to the prism 8, the resolution of the camera 14, and other conditions. In Figure 4(B), no bounding box is set for the prism 8 in the upper right corner that was not detected.

[0054] If step S03 is successful (Yes), in step S04, the approximate rotation angle calculation unit 62 calculates the approximate rotation angles θt (θtv, θth) in the vertical and horizontal directions for orienting the telescope 6c from the current orientation of the collimation optical axis A toward the center of the approximate target RT for all detected approximate targets RT. Details of the angle calculation will be described later. The approximate rotation angle calculation unit 62 outputs the calculated approximate rotation angles θt (θtv, θth) to the surveying instrument calculation unit 20 via the communication unit 52.

[0055] Next, in step S05, the outline target identification unit 63 identifies a target outline target (hereinafter referred to as the target target) RTt (FIG. 4C) to be turned around from the detected outline targets RT. Details will be described later.

[0056] Next, in step S06, the rotation drive unit 13 is driven based on the approximate rotation angle θt (approximate vertical rotation angle θtv, approximate horizontal rotation angle θth) calculated in step S04 for the set target RTt, and the telescope 6c is directed approximately in the direction of the target RTt as shown in Figure 4 (C).

[0057] Thereafter, in step S07, the precision collimation execution unit 23 executes automatic collimation using the automatic collimation unit, drives the rotation drive unit 13 so as to collimate the center O of the prism 8, performs precise collimation, and ends the process.

[0058] 5 to 7, the calculation of the approximate rotation angle in step S04 will be described in detail. When the process of calculating the approximate rotation angle starts, in step S11, the approximate rotation angle calculation unit 62 calculates the approximate distance from the surveying instrument 10 to the approximate target RT from the dimensions of the approximate target RT in the image 70. For this purpose, the correlation between the dimensions of the approximate target RT in the image 70 and the distance from the surveying instrument 10 is stored in advance in the storage unit 51.

[0059] Next, in step S12, the approximate rotation angle calculation unit 62 calculates the approximate rotation angle of the center C of the target RT in the image 70. ＲＴ The position of the surveying instrument 10 is １０ The angle θc (θcv, θch) is calculated based on the approximate center C of the target RT.ＲＴ For example, as shown in FIGS. 6A and 6B, the center of gravity G of the approximate targets RT1 and RT2 detected as segments is ＲＴ１ , G ＲＴ２ is set as:

[0060] Next, in step S13, the approximate rotation angle calculation unit 62 calculates the approximate rotation angle θt (θtv, θth) for directing the collimation optical axis A of the telescope 6c toward the approximate target RT from the approximate target position in the image and the approximate distance to the approximate target.

[0061] The horizontal approximate rotation angle θth is calculated as follows: Because the optical axis of the camera 14 coincides with the collimation optical axis A of the telescope 6c in the horizontal direction, the approximate rotation angle calculation unit 62 can calculate the angle with respect to the optical axis of the camera 14 (i.e., the collimation optical axis A of the telescope 6c) by determining the position of the pixel on the image sensor. Therefore, the approximate rotation angle calculation unit 62 calculates the horizontal approximate rotation angle θth from the difference between the current horizontal angle of the collimation optical axis A of the telescope 6c and the horizontal angle θch of the approximate target RT.

[0062] The approximate vertical rotation angle θtv can be calculated as follows. For the sake of convenience, in FIG. 7, the telescope 6c and the camera 14 are depicted separated in the vertical direction. As shown in FIG. 7, it is assumed that the collimation optical axis A of the telescope 6c and the optical axis B of the camera are horizontal. Then, the center O of the camera 14 is １４ is offset by Δp in the vertical direction from the center of the telescope 6c. Furthermore, using trigonometric functions, the approximate vertical rotation angle θtv for orienting the telescope 6c from the vertical angle of the collimation optical axis A to the approximate θcv of the target RT is calculated from the position θc(θcv, θch) of the prism 8 calculated in step S12 from the optical axis B of the camera 14 and the distance ds to the prism 8 calculated in step S11, using the following equation: θtv=tan-1{(l+Δp) / dh} (Equation 1) The calculated approximate rotation angle θt(θtv, θth) is output to the surveying instrument calculation unit 20 via the communication unit 52 of the data processing device 50 and the communication unit 19 of the surveying instrument 10. If the collimation optical axis A of the telescope 6c is not horizontal, the approximate vertical rotation angle θtv can be calculated in the same way by taking into account the deviation from horizontal (vertical angle).

[0063] Then, in step S14, it is determined whether the approximate rotation angles have been calculated for all the detected approximate targets, and steps S11 to S14 are repeated until the rotation angles have been calculated for all the approximate targets RT (until the result is Yes).

[0064] In step S11, the distance d from the surveying instrument 10 to the approximate target RT is ｓ Instead of calculating from the approximate dimensions of the target RT in the image 70, the approximate rotation angle calculation unit 62 may be configured to obtain it using a known depth estimation model such as ZoeDepth.

[0065] (Details of Identifying General Targets) Next, details of the process of identifying general targets in step S05 will be described with reference to FIG. 8. When identifying general targets RT starts, at least one general target RT has been detected. For example, as shown in FIG. 4A, an image 70 may contain multiple general targets RT, and may contain both two types of general targets RT1 and RT2. Step S05 identifies one general target to be the target of turning and rotating from among such general targets.

[0066] When the process starts, first, in step S21, the outline target identification unit 63 determines whether or not the jacket 7 (second outline target RT2) of the two outline targets has been detected in the image 70.

[0067] If the jacket 7 is detected (Yes), in step S22, the general target identification unit 63 determines whether the prism 8 (first general target RT1) is also detected. If the prism 8 is also detected (Yes), the process proceeds to step S23, where it is determined whether the approximate distance to the jacket 7 (second general target RT2) calculated in step S11 matches the approximate distance to the prism 8 (first general target RT1). Note that "match" does not require a strict match; it is sufficient to match approximately, and it is sufficient to match to the extent that it can be determined that the two are in almost the same position.

[0068] If there is a match, it is estimated that the prism 8 (first outline target RT1) is being held by the worker OP wearing the jacket 7 (second outline target RT2), as shown in the right part of the image 70 in Figure 4 (A).

[0069] Furthermore, in step S23, it is simultaneously determined whether the approximate distance to the jacket 7 (second approximate target RT2) and the approximate distance to the prism 8 (first approximate target RT1) are equal to or less than a threshold value Th. The dimensions of the jacket 7 are greater than the dimensions of the prism 8. Therefore, due to the resolution of the image sensor of the camera 14, the detection limit distance of the prism 8 is shorter than that of the jacket 7. Furthermore, at the same distance, the detection accuracy of the approximate target RT and the center C of the approximate target RT are different. ＲＴ The calculation accuracy of the jacket 7 is higher than that of the prism 8. Therefore, the prism 8 is suitable for relatively short distances (for example, 5 m or less), while the jacket 7 is suitable for relatively long distances (for example, 10 to 100 m). On the other hand, the center O of the prism 8, which is the final collimation target, is located at the center C of the jacket 7. ＲＴ２ Therefore, when the prism 8 is rotated approximately, it may not be possible to capture the prism 8 within the range of the telescope 6c at a short distance. The threshold value Th is set taking this into consideration.

[0070] In order to reliably place the prism 8 within the field of view of the telescope 6c when the jacket 7 is the target of turning, it is preferable that the operator OP always hold the prism 8 near the center of the jacket 7. However, this is not limiting, and the positional relationship between the jacket 7 and the prism 8 may be kept constant, and the approximate rotation angle θt may be calculated using this positional relationship when turning.

[0071] If, in step S23, the approximate distance to the jacket 7 and the approximate distance to the prism 8 match and are equal to or less than the threshold value (Yes), the process proceeds to step S24, where the rough target identification unit 63 designates the prism 8 closest to the jacket 7 as the target RTt, and terminates the rough target identification process. On the other hand, if, in step S23, no prism is detected, or the distance to the jacket 7 and the prism 8 (first rough target RT1) is greater than the threshold value Th (No), the detected jacket 7 (first rough target RT1) is designated as the target RTt, and the rough target identification process terminates.

[0072] Furthermore, if the jacket 7 is not detected in step S21 (No), the rough target identification unit 63 determines in step S36 whether or not multiple prisms 8 (first rough targets RT1) have been detected. This is because, at the surveying site, the operator OP does not necessarily hold the prism 8, and multiple prisms 8 (first rough targets RT1) may be installed in preset positions, and automatic collimation and measurement may be performed sequentially.

[0073] If multiple prisms 8 are detected in step S26 (Yes), the process proceeds to step S27, where the general target identification unit 63 designates the prism 8 (first general target RT1) closest to the center of the telescope 6c as the target RTt, and ends the general target identification process. On the other hand, if multiple prisms are not detected in step S26, the process proceeds to step S28, where the detected prism 8 (first general target RT1) is designated as the target RTt, and ends the general target identification process.

[0074] Furthermore, if multiple prisms are detected in step S26 (Yes), instead of step S27, the operator may be notified that multiple prisms have been detected, and this may be displayed on the display unit 18 of the surveying instrument 10, and the user may be allowed to select which prism to turn around and rotate using the input unit 17.

[0075] (Effects) In the surveying system 1 according to this embodiment, the camera 14 is provided in the surveying instrument 10, and the camera 14 is configured to detect a rough target from an image acquired by the camera 14 at a wider angle than the telescope's field of view, calculate an approximate rotation angle for pointing the telescope 6c toward the rough target from that position, and then perform rough turning rotation. As a result, faster automatic aiming is possible compared to conventional systems. With the above configuration, the automatic turning function can be added simply by adding the camera 14 to a conventional surveying instrument, thereby achieving the unique effect of providing a surveying system with an automatic turning function at a relatively low cost.

[0076] Furthermore, in the surveying system 1, two types of approximate targets RT are set, each having different dimensions: a prism 8 and the worker's jacket (clothing) 7. In relation to the resolution of the image 70, the prism 8 is set as the turning target within the distance range within the threshold Th at which the prism 8 can be detected, and the jacket 7 is set as the turning target within the distance range outside the threshold Th. This makes it possible to realize an approximate turning function over a wider distance range than when only one of the targets is set as the approximate target RT.

[0077] However, this does not mean that the present invention is limited to using two types of outline targets RT, and one type may be used. For example, in a distance range where the prism 8 can be detected with appropriate accuracy, only the prism 8 may be set as the outline target RT. In that case, the process of setting the target RTt can be executed as shown in FIG. 9. The process contents of steps S31 to S33 are the same as steps S26, S27, and S28.

[0078] In the above explanation, the prism 8 and the worker's jacket 7 are set as the general target RT, but this is not limiting, and a highly visible object (for example, a flat plate colored in a predetermined color) may be attached near the prism 8 and used as the general target RT. However, by setting the prism 8 and the worker's jacket 7, existing elements that have been used conventionally for using a surveying system, as the general target RT, there is no need to use a new element as the general target RT.

[0079] Furthermore, in the above explanation, an example has been given in which the turning-around function according to this embodiment is used as a function preceding automatic aiming, but it goes without saying that if the surveying instrument 10 has an automatic tracking function, the surveying instrument 10 can be configured to execute the automatic tracking function after roughly capturing the target RT using the turning-around function.

[0080] 2. Second Embodiment Fig. 10 is a configuration block diagram of a surveying system 100 according to the second embodiment. The surveying system 100 is a total station having a mechanical configuration equivalent to that of the surveying instrument 10 constituting the surveying system 1 according to the first embodiment. The hardware configuration of the control and calculation unit 130 is also equivalent to that of the surveying instrument calculation unit 20 of the surveying instrument 10. However, in the surveying system 1, the surveying instrument calculation unit 20 includes a wide-angle image acquisition unit 21, a rough rotation execution unit 22, and a fine collimation execution unit 23, and further includes a separate data processing device 50, and the processing device calculation unit 60 includes a rough target detection unit 61, a rough rotation angle calculation unit 62, and a rough target identification unit 63, and the surveying instrument calculation unit 20 and the processing device calculation unit 60 cooperate to function as the control and calculation unit 30 of the surveying system 1.

[0081] On the other hand, in the surveying system 100, the control and calculation unit 130 includes a wide-angle image acquisition unit 131, a rough target detection unit 132, a rough rotation angle calculation unit 133, a rough target identification unit 134, a rough rotation execution unit 135, and a precision collimation execution unit 136. Other points are the same as those of the surveying system 1.

[0082] In this way, even if the surveying system is configured as a single total station rather than being configured with the surveying instrument 10 and the data processing device 50, it is possible to achieve the same effects as in the first embodiment.

[0083] 11 is a block diagram of a configuration of a surveying system 100A according to a modification of the surveying system 100 according to the second embodiment. The surveying system 100A has the same configuration as the surveying system 100, except for the following points.

[0084] In the surveying system 100, the camera 14 is attached to a handle provided on the top of the support section 6b, whereas in the surveying system 100A, the camera 14A is provided on the telescope 6cA, and the optical axis of the camera 14A is configured to be coaxial with the collimation optical axis A of the telescope 6c, which is the distance measurement optical axis.

[0085] In addition, the objective lens 6d shared by the telescope 6cA and the camera 14A has a zoom function, and the angle of view can be adjusted between 1.5° x 1.5° (vertical x horizontal), which is the same as that of the telescope 6c, and 10° x 15° (vertical x horizontal), which is the same as that of the camera 14.

[0086] In this way, if the camera 14A is configured coaxially with the telescope 6cA, when calculating the approximate vertical rotation angle θtv, the angle with respect to the optical axis of the camera 14 (i.e., the collimation optical axis A of the telescope 6cA) can be calculated by determining the position of the pixel on the image sensor of the camera 14A, just as with the approximate horizontal rotation angle θth. Therefore, step S11 for calculating the approximate distance to calculate the approximate vertical rotation angle can be omitted. Furthermore, the calculation process of step S13 can also be made easier.

[0087] Furthermore, since the camera 14A is provided inside the telescope 6c, the external appearance of the surveying system 100A can be made more compact than that of the surveying system 100, which is an additional effect.

[0088] In order to set the target target RTt, it is necessary to calculate the approximate distance to the approximate target RT, but in this modified example, it is only necessary to calculate the approximate distance for the approximate target RT related to the judgment in step S23, so the burden of calculation processing is reduced for the surveying system 100 which needs to calculate the approximate distance for all the approximate targets RT. In addition, this modified example can also be applied to the surveying system 1 according to the first embodiment.

[0089] 4. Other Modifications The following modifications may also be made. (1) There may be multiple types of prisms 8 (prisms 8a, 8b, and 8c) used in the surveying system 1 according to the first embodiment, as shown in FIG. 12 . In such a case, three types of reference data, such as first rough targets RT1a, RT1c, and RT1c, may be registered based on the image of each prism, depending on the object detection model applied to the rough target detection unit 61, so that each prism can be detected individually. In this way, even when multiple prisms are mixed, prisms can be accurately detected, reducing the likelihood of detection errors and improving work efficiency.

[0090] Furthermore, when registering the reference data 80, it is possible to register not only a front image of one type of rough target RT2 as shown in the left diagram of Fig. 13, but also multiple images such as a side image or a back image (not shown) as shown in the right diagram, or images of different orientations. This is because doing so improves the detection accuracy of the rough target RT. Such modifications may also be applied to the surveying system 100 according to the second embodiment and its modified examples.

[0091] (2) In the surveying system 1 according to the first embodiment, when a surveying operation is performed according to CAD design data, whether to set the first or second rough target may be determined based on the distance from the installation point of the surveying instrument to the measurement point, which is determined from the CAD design data, during the process of setting the rough target. Such a modification may be applied to the surveying system 100 according to the second embodiment and its modified examples.

[0092] (3) In the surveying system 1 according to the first embodiment, when the image 70 is acquired by the camera 14, the surveying instrument 10 is rotated in the horizontal direction while the image 70 is acquired. １ , 70 ２， 70 ３ ..., multiple shots may be taken to obtain a panoramic image 70A such as that shown in Fig. 14. This allows for a wider range of target search, and makes it possible to detect targets that would not be captured in the angle of view by only taking images in the collimation direction. This allows for faster target capture.

[0093] 15, when the turning-around function is executed, in step S01, the wide-angle image acquisition unit 21 acquires an image 70 of the field of view of the camera 14. Only if the general target detection unit 61 fails to detect the general target RT in step S03, the process proceeds to step S08 to acquire a panoramic image 70A, and then, in step S02 again, the general target RT is detected in the panoramic image 70A. In this way, the panoramic image 70A is acquired only if the general target RT is not detected with a normal field of view, making it possible to search for the prism 8 more quickly and over a wider range. Such a modification may be applied to the surveying system 100 according to the second embodiment and its modifications.

[0094] DESCRIPTION OF SYMBOLS 1, 100, 100A: Surveying system 6c: Telescope 7: Jacket (clothing) 8: Prism 11: Distance measuring device 12: Angle detector 13: Rotation drive unit 14: Camera 21, 131: Wide-angle image acquisition unit 22, 135: Coarse rotation execution unit 23, 136: Fine collimation execution unit 30, 130: Control and calculation unit 61, 132: Coarse target detection unit 62, 133: Coarse rotation angle calculation unit 63, 134: Coarse target identification unit RT: Coarse target RT1: First coarse target RT2: Second coarse target RTt: Target coarse target

Claims

1. A surveying system comprising: a distance measuring device housed in a telescope, which sends distance measuring light to a prism and receives the light reflected from the prism to measure the distance to the center of the prism; an angle detector which detects the angle of the collimation optical axis of the telescope; a rotation drive unit which drives and rotates the telescope; a camera which has a field of view wider than the field of view of the telescope and captures an image in front of the telescope; and a control and calculation unit which has at least one electronic circuit and at least one memory; wherein a general target for roughly turning the prism is set, and the control and calculation unit is configured to: detect the general target from the image; calculate a general rotation angle for roughly turning the collimation optical axis of the telescope toward the general target based on the position of the general target; set a target general target to be turned towards from the general target in the image; and drive the rotation drive unit to rotate the telescope by the general rotation angle.

2. The surveying system according to claim 1, characterized in that the outline targets include a first outline target and a second outline target having dimensions larger than the first outline target, and the target outline target is set according to the approximate distance to the first outline target and the approximate distance to the second outline target.

3. The surveying system according to claim 2, wherein the first outline target is the prism, and the second outline target is clothing of a worker holding the prism.

4. The surveying system according to claim 1, wherein the general target is the prism.

5. A surveying system as described in claim 1 or 2, characterized in that the camera is provided inside the telescope so that its optical axis is coaxial with the collimation optical axis of the telescope, and the telescope and the objective lens of the camera are configured to be zoomable.

6. A surveying system as described in claim 1 or 3, characterized in that the camera is provided at a distance from the telescope, the position and direction relationship between the camera and the telescope is known, and the control and calculation unit calculates the approximate distance to the approximate target based on the size of the approximate target in the image.

7. The surveying system according to claim 1 or 2, characterized in that the control and calculation unit detects the approximate target from the input image by applying an object detection model that detects the approximate target from the image using machine learning.

8. A surveying system according to claim 1 or 2, characterized in that the control and calculation unit controls the rotary drive unit and the camera to acquire a panoramic image in front of the telescope, and detects the approximate target from the panoramic image.

Images