Surveying System

Abstract

To provide a surveying system capable of more reliably tracking a measurement object.SOLUTION: A surveying system includes a measurement object and a measuring device body 3. The measuring device body 3 includes: a range finding light emission part 25; a light reception part 26; a range finding part 42; a light axis deflection part 35; an emission direction detection part 38; and an arithmetic control part 28. The arithmetic control part 28 controls a two-dimensional scan by a scan pattern having a cross point that a going passage and a return passage of a two-dimensional scan cross, updates three-dimensional data of a measurement object each time when detecting a light reception signal during the two-dimensional scan, generates weighting for detecting a reference point and weighting for detecting a rotational angle of a measurement object according to distance from an intersection each time when three-dimensional data are updated, and tracks a measurement object on the basis of a reference point position and a rotational angle of the measurement object calculated by using weighting.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a surveying system having a tracking function. [Background technology]

[0002] A total station is an example of a surveying system with a tracking function. A total station collimates a measurement target with a high-magnification telescope that also serves as a distance measurement optical system, performs measurement, and then rotates the telescope horizontally and vertically to collimate a different measurement target, and performs measurement by sequentially collimating each different measurement target. Alternatively, a total station rotates the telescope horizontally and vertically in accordance with the movement of the measurement target, tracks the measurement target, and collimates the measurement target to perform measurement.

[0003] However, when a surveying system tracks a measurement target, if the measurement target moves quickly, the surveying system may not be able to track the movement of the measurement target and may lose sight of the measurement target. Once the surveying system loses sight of the measurement target, it searches for the measurement target, but it may take time to capture the measurement target. Therefore, when the measurement target moves quickly, the inability of the surveying system to track the measurement target is a factor that reduces the workability of the measurement. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-196983 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made to solve the above-mentioned problems, and has an object to provide a surveying system that can more reliably track a measurement target. [Means for solving the problem]

[0006] The problem is to provide a surveying system including a measurement target having a retroreflector, and a measurement device main body that emits distance measurement light and measures the measurement target based on the distance measurement light reflected from the retroreflector, the measurement device main body including a distance measurement light emitting unit having a light emitting element that emits the distance measurement light and emits the distance measurement light onto a distance measurement light axis, a light receiving unit having a light receiving element that receives the reflected distance measurement light and generates a light receiving signal, a distance measuring unit that measures the distance of the measurement target based on the light receiving signal from the light receiving element, an optical axis deflection unit having a reference optical axis and deflecting the distance measurement optical axis with respect to the reference optical axis, an emission direction detection unit that detects the deflection angle and the direction of the deflection angle of the distance measurement optical axis with respect to the reference optical axis, and a calculation control unit that controls the deflection action of the optical axis deflection unit and the distance measurement action of the distance measuring unit, the optical axis deflection unit including a pair of optical prisms that are rotatable around the reference optical axis, and a motor that rotates the optical prisms independently of one another. The problems are solved by the surveying system of the present invention, characterized in that the calculation control unit controls the deflection by the optical axis deflection unit by controlling the rotation direction, rotation speed, and rotation ratio of the pair of optical prisms, performs a two-dimensional scan with the distance measurement light approximately centered on the distance measurement optical axis, and controls the two-dimensional scan with a scan pattern having an intersection where the outward and return paths of the two-dimensional scan intersect, updates the three-dimensional data of the measurement object based on the deflection angle data as the detection result by the emission direction detection unit and the distance measurement data as the detection result by the distance measurement unit each time the light receiving signal is detected during the two-dimensional scan, generates weighting for detecting a reference point and a rotation angle of the measurement object in accordance with the distance from the intersection each time the three-dimensional data is updated, and tracks the measurement object based on the reference point position and rotation angle of the measurement object calculated using the weighting.

[0007] According to the surveying system of the present invention, the calculation control unit controls the deflection by the optical axis deflection unit, executes a two-dimensional scan with the distance measurement light centered approximately on the distance measurement optical axis, and controls the two-dimensional scan with a scan pattern having an intersection where the forward and backward paths of the two-dimensional scan intersect. Then, the calculation control unit updates three-dimensional data of the measurement object based on the deflection angle data as the detection result by the emission direction detection unit and the distance measurement data as the detection result by the distance measurement unit every time a light receiving signal is detected during the two-dimensional scan. In this way, since the calculation control unit acquires and updates the three-dimensional data every time a light receiving signal is detected during the two-dimensional scan, the measurement object can be tracked at high speed even if a predetermined amount of three-dimensional data is not accumulated. At this time, the calculation control unit generates weighting for detecting the reference point and the rotation angle of the measurement object according to the distance from the intersection of the scan pattern every time the three-dimensional data is updated, and tracks the measurement object based on the reference point position and the rotation angle of the measurement object calculated using the weighting. Therefore, even if the calculation control unit acquires and updates 3D data every time a light receiving signal is detected during a 2D scan, the calculation control unit can reduce the time required for calculation processing and track the measurement target at high speed. As a result, the surveying system according to the present invention can prevent the measurement target from being lost and can track the measurement target more reliably.

[0008] In the surveying system according to the present invention, the calculation control unit preferably generates the weighting for detecting the reference point so that the closer the distance from the intersection, the larger the value.

[0009] According to the surveying system of the present invention, the calculation control unit generates weighting for detecting the reference point of the measurement object so that the closer the distance from the intersection of the scan pattern is, the larger the weighting value is. Therefore, the calculation control unit can detect the reference point of the measurement object with higher accuracy. As a result, the surveying system of the present invention can track the measurement object more reliably.

[0010] In the surveying system according to the present invention, the calculation control unit preferably generates the weighting for detecting the rotation angle so that the value becomes larger as the distance from the intersection increases.

[0011] According to the surveying system of the present invention, the calculation control unit generates weighting for detecting the rotation angle of the measurement object so that the weighting value increases as the distance from the intersection of the scan pattern increases. Therefore, the calculation control unit can detect the rotation angle of the measurement object with higher accuracy. This allows the surveying system of the present invention to track the measurement object more reliably.

[0012] In the surveying system of the present invention, preferably, the calculation control unit further generates first correction data obtained by folding back the intensity distribution of the received light signal on one of the orthogonal coordinate axes in the two-dimensional scan, and second correction data obtained by folding back the intensity distribution of the received light signal on the other of the orthogonal coordinate axes, for use in detecting the rotation angle of the object to be measured, and tracks the object to be measured based on the rotation angle calculated using the weighting for detecting the rotation angle generated according to the distance from the intersection, and at least one of the first correction data and the second correction data.

[0013] According to the surveying system of the present invention, the calculation control unit further generates first correction data for detecting the rotation angle of the measurement object by folding back the intensity distribution of the received light signal on one of the orthogonal coordinate axes in the two-dimensional scan. The calculation control unit further generates second correction data for detecting the rotation angle of the measurement object by folding back the intensity distribution of the received light signal on the other of the orthogonal coordinate axes in the two-dimensional scan. Then, the calculation control unit tracks the measurement object based on the rotation angle of the measurement object calculated using the weighting for detecting the rotation angle generated according to the distance from the intersection of the scan pattern and at least one of the first correction data and the second correction data. Therefore, even when the calculation control unit generates the weighting for detecting the reference point and the weighting for detecting the rotation angle of the measurement object according to the distance from the intersection of the scan pattern, it is possible to prevent the intensity distributions of the received light signal from canceling each other out. As a result, the surveying system of the present invention can more reliably track the measurement object.

[0014] In the surveying system of the present invention, the calculation control unit is preferably characterized in that it generates the first correction data by folding back the intensity distribution of the received light signal on one coordinate axis, and then further inverting only the intensity distribution folded back on the one coordinate axis around the other coordinate axis, and generates the second correction data by folding back the intensity distribution of the received light signal on the other coordinate axis, and then further inverting only the intensity distribution folded back on the other coordinate axis around the one coordinate axis.

[0015] According to the surveying system of the present invention, the calculation control unit generates first correction data by folding back the intensity distribution of the received light signal on one coordinate axis, and then further inverting only the intensity distribution folded back on one coordinate axis around the other coordinate axis. Also, the calculation control unit generates second correction data by folding back the intensity distribution of the received light signal on the other coordinate axis, and then further inverting only the intensity distribution folded back on the other coordinate axis around the one coordinate axis. Therefore, even if the measurement target does not extend in the vertical and horizontal directions, that is, even if the measurement target is inclined with respect to the vertical and horizontal directions, it is possible to prevent the intensity distributions of the received light signals from canceling each other out. This allows the surveying system of the present invention to more reliably track the measurement target. Effect of the Invention

[0016] According to the present invention, it is possible to provide a surveying system that can more reliably track a measurement target. [Brief description of the drawings]

[0017] [Figure 1] 1 is a perspective view showing an outline of a surveying system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a front view showing a surveying device main body of the surveying system according to the present embodiment. [Diagram 3] 1 is a block diagram showing a schematic configuration of a surveying device main body of the present embodiment. [Figure 4] 5A to 5C are schematic diagrams illustrating the operation of an optical axis deflection unit according to the present embodiment. [Diagram 5] FIG. 2 is a schematic diagram illustrating an example of a scan pattern. [Figure 6] FIG. 13 is a schematic diagram illustrating another example of a scan pattern. [Figure 7] FIG. 2 is a schematic diagram illustrating the relationship between a scan pattern and a target device. [Figure 8] FIG. 2 is a block diagram showing a schematic configuration of an arithmetic and control unit of the present embodiment. [Figure 9]1A is a schematic diagram showing a first specific example of folding back and inverting the intensity distribution of a light receiving signal from a light receiving element. FIG. [Figure 10] 13 is a schematic diagram showing a second specific example in which the intensity distribution of a received light signal from a light receiving element is folded back and inverted. FIG. [Figure 11] 13 is a schematic diagram showing a third specific example in which the intensity distribution of a received light signal from a light receiving element is folded back and inverted. FIG. [Figure 12] 13 is a schematic diagram showing a fourth specific example in which the intensity distribution of a received light signal from a light receiving element is folded back and inverted. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below are preferred specific examples of the present invention, and therefore various technically preferable limitations are applied to them, but the scope of the present invention is not limited to these aspects unless otherwise specified in the following description to the effect that the present invention is limited to them. In addition, in each drawing, similar components are given the same reference numerals, and detailed descriptions thereof are omitted as appropriate.

[0019] FIG. 1 is a perspective view showing an outline of a surveying system according to an embodiment of the present invention. FIG. 2 is a front view showing the main body of the surveying device of the surveying system according to this embodiment. FIG. 3 is a block diagram showing a schematic configuration of the surveying instrument body of this embodiment.

[0020] The surveying system 1 in this embodiment mainly comprises a tripod 2 as a support device, a surveying device main body 3 as an electronic range finder, an installation stand 4 on which the surveying device main body 3 is attached, a target device 5 installed at a measurement point P, and a terminal device 6 capable of remotely operating the surveying device main body 3.

[0021] The terminal device 6 is a portable device having a display function, a communication function, and a calculation processing function. For example, a smartphone, a tablet, a notebook computer, etc., is used as the terminal device 6. The terminal device 6 transmits measurement-related instructions to the surveying device main body 3, receives measurement data, image data, etc. acquired by the surveying device main body 3, and performs data storage, data display, data processing, etc.

[0022] The installation base 4 is attached to the upper end of the tripod 2. The surveying instrument main body 3 is provided on the installation base 4. The installation base 4 supports the surveying instrument main body 3 so that it can rotate.

[0023] The target device 5 has a pole 83 which is a rod-shaped support member with a circular cross section, and a reference reflecting part 84 which is provided as a target midway along the pole 83. The reference reflecting part 84 is circular and concentric with the pole 83, and a reflective sheet which is a retroreflective member is wrapped around the entire circumference of the reference reflecting part 84.

[0024] A reflective sheet, which is a retroreflective material, is wrapped around the pole 83 so that the pole 83 is partially exposed at both the top and bottom and covers the entire circumference. The portion around which the reflective sheet is wrapped constitutes a linear reflective portion 85 having a predetermined length at the top and bottom. The reference reflective portion 84 and the linear reflective portion 85 each reflect distance measuring light and are the measurement objects of the surveying system 1. In comparison with the reference reflective portion 84 which serves as a target indicating a reference point (described below), the linear reflective portion 85 serves as an auxiliary reflective portion which facilitates detection of the measurement object and further detection of the reference reflective portion 84.

[0025] The lower end of the pole 83 is formed into a pointed tip so that a measurement point P can be indicated.

[0026] The target device 5 has a reference point at a predetermined position from the bottom end of a pole 83. A reference reflecting portion 84 is provided on the pole 83, and the reference point is the center of the reference reflecting portion 84. The distance between the reference point and the bottom end of the pole 83 is known.

[0027] Similar to the linear reflecting portion 85, a reflecting sheet is wrapped around the entire circumference of the reference reflecting portion 84. The reference reflecting portion 84 has a predetermined thickness (length in the axial direction) larger than the beam diameter of the distance measuring light, and is thicker than the diameter of the linear reflecting portion 85.

[0028] Here, the diameter difference between the reference reflecting part 84 and the linear reflecting part 85 is determined in accordance with the measurement accuracy of the surveying device main body 3. This diameter difference needs to be equal to or greater than the measurement accuracy (measurement error) of the surveying device main body 3. In other words, it is sufficient if the reference reflecting part 84 and the linear reflecting part 85 can be distinguished based on the distance measurement results between them. It goes without saying that the diameter difference is determined in accordance with the diameter of the linear reflecting part 85, the measurement conditions, the measurement capabilities of the surveying device main body 3, etc.

[0029] For example, assuming that the maximum measurement distance is 200 m, the diameter of the linear reflecting portion 85 is set to 35 mm, the diameter of the reference reflecting portion 84 to 100 mm, and the thickness of the reference reflecting portion 84 to 30 mm. However, the diameter of the linear reflecting portion 85, the diameter of the reference reflecting portion 84, and the thickness of the reference reflecting portion 84 are not limited to these.

[0030] A support part 11 is provided on the installation base 4 so as to be rotatable in the horizontal direction. A horizontal rotation shaft 12 protrudes from the underside of the support part 11. The horizontal rotation shaft 12 is rotatably fitted to the installation base 4 via a bearing (not shown). The support part 11 is rotatable in the horizontal direction around the horizontal rotation shaft 12.

[0031] In addition, a horizontal angle detector 13 (e.g., an encoder) that detects a horizontal angle (angle in the rotation direction around the horizontal rotation shaft 12) is provided between the horizontal rotation shaft 12 and the installation base 4. The horizontal angle detector 13 detects the horizontal relative rotation angle of the support unit 11 with respect to the installation base 4.

[0032] A horizontal rotation gear 14 is fixed to the installation base 4 concentrically with the horizontal rotation shaft 12, and a horizontal pinion gear 15 meshes with the horizontal rotation gear 14. A horizontal motor 16 is provided on the support unit 11, and the output shaft of the horizontal motor 16 protrudes downward. The horizontal pinion gear 15 is fixed to the output shaft of the horizontal motor 16.

[0033] When the horizontal motor 16 is driven, the horizontal pinion gear 15 rotates, and the horizontal pinion gear 15 revolves around the horizontal rotation gear 14. Furthermore, since the base part 11 and the surveying instrument main body 3 are integral with each other, the horizontal motor 16 rotates the surveying instrument main body 3 in the horizontal direction around the horizontal rotation axis 12.

[0034] The base part 11 has a concave shape with a recess, and the recess houses the surveying device main body 3. The surveying device main body 3 is supported by the base part 11 via a vertical rotation shaft 17 having a horizontal axis extending horizontally, and the surveying device main body 3 is freely rotatable in the vertical direction around the vertical rotation shaft 17.

[0035] A vertical rotation gear 18 is fixed to one end of the vertical rotation shaft 17, and a pinion gear 19 meshes with the vertical rotation gear 18. A vertical motor 21 is provided on the base unit 11, and the pinion gear 19 is fixed to the output shaft of the vertical motor 21. When the vertical motor 21 is driven, the surveying device main body 3 is rotated in the vertical direction via the pinion gear 19, the vertical rotation gear 18, and the vertical rotation shaft 17.

[0036] In addition, a vertical angle detector 22 (e.g., an encoder) that detects a vertical angle (angle in the rotation direction around the vertical rotation shaft 17) is provided between the vertical rotation shaft 17 and the base unit 11. The vertical angle detector 22 detects the relative rotation angle of the surveying device main body 3 with respect to the base unit 11 in the vertical direction.

[0037] The horizontal motor 16, the vertical motor 21, the horizontal angle detector 13, and the vertical angle detector 22 are electrically connected to an arithmetic control unit 28 (described later), and the horizontal motor 16 and the vertical motor 21 are each individually driven and controlled by the arithmetic control unit 28 so as to achieve the required amount of rotation at the required timing.

[0038] The amount of rotation of the horizontal motor 16 (i.e., the horizontal angle of the support unit 11) is detected by a horizontal angle detector 13. The amount of rotation of the vertical motor 21 (i.e., the vertical angle of the surveying instrument main body 3) is detected by a vertical angle detector 22.

[0039] The detection results of the horizontal angle detector 13 and the vertical angle detector 22 are input to the calculation control unit 28. The horizontal motor 16 and the vertical motor 21 form a rotation drive unit. The horizontal angle detector 13 and the vertical angle detector 22 form an angle detector that detects the vertical rotation angle and the horizontal rotation angle of the surveying instrument main body 3, i.e., a direction angle detector.

[0040] The schematic configuration of the surveying instrument main body 3 will be described with reference to FIG.

[0041] The surveying device main body 3 has a distance measurement light emitting unit 25, a light receiving unit 26, a distance measurement calculation unit 27, a calculation control unit 28, a memory unit 29, an imaging control unit 31, an image processing unit 32, a communication unit 33, an optical axis deflection unit 35, an attitude detector 36, a measurement direction imaging unit 37, an emission direction detection unit 38, and a motor driver 39. These are housed and integrated in a housing 41. The distance measurement light emitting unit 25, the light receiving unit 26, the distance measurement calculation unit 27, the optical axis deflection unit 35, etc. constitute a distance measurement unit 42 that functions as an optical distance meter.

[0042] The distance measurement light emitting unit 25 has an emission optical axis 44, and a light emitting element 45, for example a laser diode (LD), is provided on the emission optical axis 44. A projector lens 46 is also provided on the emission optical axis 44. A first reflecting mirror 47 serving as a deflection optical member is also provided on the emission optical axis 44. A second reflecting mirror 48 serving as a deflection optical member is disposed at a position where the emission optical axis 44 deflected by the first reflecting mirror 47 intersects with a receiving optical axis 51 (described later). The emission optical axis 44 is deflected by the second reflecting mirror 48 so as to coincide with the receiving optical axis 51. The first reflecting mirror 47 and the second reflecting mirror 48 constitute an emission optical axis deflection unit.

[0043] A CPU specialized for this device or a general-purpose CPU is used as the distance measurement calculation unit 27. The distance measurement calculation unit 27 drives the light-emitting element 45, which emits a laser beam. The distance measurement light emission unit 25 emits the laser beam emitted from the light-emitting element 45 as distance measurement light 49. The laser beam may be any of continuous light, pulsed light, or intermittently modulated light (i.e., burst light).

[0044] The light receiving unit 26 will now be described. The light receiving unit 26 has an optical system and a light receiving element for receiving reflected distance measuring light 52 from the measurement target (i.e., the reference reflecting unit 84 and the linear reflecting unit 85). The light receiving unit 26 has a light receiving optical axis 51, which coincides with the exiting optical axis 44 deflected by the first reflecting mirror 47 and the second reflecting mirror 48. The state in which the exiting optical axis 44 and the light receiving optical axis 51 coincide with each other is referred to as a distance measuring optical axis 53.

[0045] The optical axis deflection unit 35 is disposed on the reference optical axis O. The optical axis deflection unit 35 deflects the laser beam passing through the optical axis deflection unit 35 by the optical action of a prism (described later). A straight optical axis passing through the center of the optical axis deflection unit 35 is the reference optical axis O. The reference optical axis O coincides with the emission optical axis 44, the light receiving optical axis 51, or the distance measuring optical axis 53 when not deflected by the optical axis deflection unit 35.

[0046] The reflected distance measuring light 52 passes through the optical axis deflection unit 35 and enters the light receiving unit 26. An imaging lens 54 is disposed on the light receiving optical axis 51, and a light receiving element 55, for example, a photodiode (PD) or an avalanche photodiode (APD), is also disposed on the light receiving optical axis 51.

[0047] The imaging lens 54 forms an image of the reflected distance measuring light 52 on the light receiving element 55. The light receiving element 55 receives the reflected distance measuring light 52 and generates a light receiving signal. The light receiving signal is input to the distance measuring calculation unit 27, which calculates the round trip time of the distance measuring light based on the light receiving signal, and measures the distance to the measurement target (i.e., the reference reflector 84 and the linear reflector 85) based on the round trip time and the speed of light.

[0048] The communication unit 33 transmits data such as image data acquired by the measurement direction imaging unit 37, image data processed by the image processing unit 32, and distance measurement data acquired by the distance measurement unit 42 to the terminal 6, and also receives data such as operation commands from the terminal 6.

[0049] A storage medium such as a HDD, a semiconductor memory, a memory card, etc. is used as the storage unit 29. Various programs are stored in the storage unit 29, such as an imaging control program, an image processing program, a distance measurement program, a display program, a communication program, an operation command creation program, an inclination angle calculation program for calculating the inclination angle and the inclination direction of the surveying device main body 3 based on the attitude detection result from the attitude detector 36, a measurement program for performing distance measurement, a deflection control program for controlling the deflection operation of the optical axis deflection unit 35, a calculation program for performing various calculations, a searching program for searching for a measurement target, a tracking program for tracking a measurement target, etc.

[0050] Moreover, the storage unit 29 stores various data such as distance measurement data, angle measurement data, image data, etc.

[0051] A CPU specialized for this device or a general-purpose CPU is used as the calculation control unit 28. The calculation control unit 28 develops and executes various programs according to the operating state of the surveying device main body 3 to control the distance measurement light emitting unit 25, the light receiving unit 26, the distance measurement calculation unit 27, the optical axis deflection unit 35, the measurement direction imaging unit 37, and the like, by the surveying device main body 3, and executes search, tracking, and distance measurement of the measurement target.

[0052] The optical axis deflection unit 35 will be described with reference to FIG.

[0053] The optical axis deflection unit 35 is composed of a pair of optical prisms 57, 58. The optical prisms 57, 58 are each a disk shape of the same diameter, and are arranged concentrically on the distance measurement optical axis 53 (i.e., the reference optical axis O) deflected by the second reflecting mirror 48, perpendicular to the distance measurement optical axis 53, and are arranged in parallel at a predetermined interval.

[0054] Each of the optical prisms 57 and 58 is composed of three triangular prisms arranged in parallel. Each triangular prism is made of optical glass and has the optical characteristic of having the same deviation angle.

[0055] The width and shape of the triangular prisms may all be the same or may be different. The width of the triangular prism located in the center is larger than the beam diameter of the distance measurement light 49, so that the distance measurement light 49 passes only through the central triangular prism. The peripheral triangular prisms may be made up of many small triangular prisms.

[0056] Furthermore, the central triangular prism may be made of optical glass, and the peripheral triangular prisms may be made of optical plastics. This is because the distance from the optical axis deflection unit 35 to the measurement object is large, and the optical characteristics of the central triangular prism require precision, whereas the distance from the peripheral triangular prisms to the light receiving element 55 is small, and high-precision optical characteristics are not required.

[0057] The central part of the optical axis deflection unit 35 is a distance measurement light deflection unit, which is a first optical axis deflection unit through which the distance measurement light 49 passes and is emitted. The rest of the optical axis deflection unit 35 (the peripheral triangular prisms) is a reflected distance measurement light deflection unit, which is a second optical axis deflection unit through which the reflected distance measurement light 52 passes and is incident.

[0058] The optical prisms 57 and 58 are disposed so as to be independently rotatable about the reference optical axis O. The optical prisms 57 and 58 are independently controlled in rotation direction, rotation amount, and rotation speed, thereby deflecting the emission optical axis 44 of the emitted distance measuring light 49 in an arbitrary direction and deflecting the receiving optical axis 51 of the received reflected distance measuring light 52 in parallel with the emission optical axis 44.

[0059] Moreover, by continuously controlling the rotation of the optical prisms 57 and 58 while continuously irradiating the distance measurement light 49 and continuously deflecting the transmitting distance measurement light 49, the distance measurement light 49 can be scanned in a predetermined pattern. Moreover, distance measurement data is acquired along the scan path (scan trajectory).

[0060] The outer shape of the optical prisms 57, 58 is a circle centered on the distance measurement optical axis 53 (reference optical axis O), and the diameters of the optical prisms 57, 58 are set in consideration of the spread of the reflected distance measurement light 52 so as to obtain a sufficient amount of light.

[0061] A ring gear 59 is fitted around the outer periphery of the optical prism 57 , and a ring gear 60 is fitted around the outer periphery of the optical prism 58 .

[0062] A drive gear 61 meshes with the ring gear 59, and the optical prism 57 is rotated by a motor 63 via the drive gear 61 and the ring gear 59. Similarly, a drive gear 62 meshes with the ring gear 60, and the optical prism 58 is rotated by a motor 64 via the drive gear 62 and the ring gear 60. The motors 63 and 64 are electrically connected to a motor driver 39.

[0063] The motors 63, 64 are motors capable of detecting the rotation angle or motors that rotate in response to a drive input value, such as pulse motors. Alternatively, the rotation amount of the motors 63, 64 may be detected using a rotation angle detector that detects the rotation amount (rotation angle) of the motor, such as an encoder. The rotation amounts of the motors 63, 64 are detected, and the motor drivers 39 control the motors 63, 64 individually.

[0064] Furthermore, the rotation angles of the optical prisms 57, 58 are detected through the rotation amounts of the motors 63, 64, i.e., the rotation amounts of the drive gears 61, 62. It is also possible to directly attach encoders to the ring gears 59, 60, respectively, and directly detect the rotation angles of the ring gears 59, 60 by the encoders.

[0065] The drive gears 61 and 62 and the motors 63 and 64 are provided at positions where they do not interfere with the distance measurement light emitting unit 25, for example, below the ring gears 59 and 60.

[0066] The light projecting lens 46, the first reflecting mirror 47, the second reflecting mirror 48, the distance measuring light deflection section, etc. constitute a light projecting optical system, while the reflected distance measuring light deflection section, the imaging lens 54, etc. constitute a light receiving optical system.

[0067] The distance measurement calculation unit 27 controls the light emitting element 45 to emit a pulse or burst (intermittent) laser beam as the distance measurement light 49. The emission optical axis 44 (i.e., the distance measurement optical axis 53) is deflected by the central triangular prism (distance measurement light deflection unit) so that the distance measurement light 49 is directed toward the measurement target. Distance measurement is performed with the distance measurement optical axis 53 collimated to the measurement target.

[0068] The reflected distance measuring light 52 reflected from the measurement target passes through a surrounding triangular prism (that is, a reflected distance measuring light deflection section) and enters the light receiving section 26 . The reflected distance measuring light 52 is then imaged on a light receiving element 55 by an imaging lens 54 .

[0069] The light receiving element 55 sends a light receiving signal to the distance measurement calculation unit 27, and the distance measurement calculation unit 27 measures the distance of the measurement point (the point where the distance measurement light is irradiated) for each pulse of light based on the light receiving signal from the light receiving element 55, and the distance measurement data is stored in the memory unit 29.

[0070] The emission direction detection unit 38 detects the rotation angles of the motors 63, 64 by counting the drive pulses input to the motors 63, 64. Alternatively, the emission direction detection unit 38 detects the rotation angles of the motors 63, 64 based on a signal from an encoder. In addition, the emission direction detection unit 38 calculates the rotation positions of the optical prisms 57, 58 based on the rotation angles of the motors 63, 64.

[0071] Furthermore, the emission direction detection unit 38 calculates in real time the deviation angle and emission direction of the distance measurement light 49 with respect to the reference optical axis O for each pulse of light, based on the refractive index of the optical prisms 57, 58, the rotational position of the optical prisms 57, 58 when integrated, and the relative rotation angle between the two optical prisms 57, 58. The calculation result (angle measurement result) is input to the calculation control unit 28 in association with the distance measurement result. Note that when the distance measurement light 49 is emitted in bursts, distance measurement is performed for each intermittent distance measurement light.

[0072] The calculation control unit 28 controls the relative rotation and overall rotation of the optical prisms 57, 58 by controlling the rotation direction and rotation speed of the motors 63, 64 and the rotation ratio between the motors 63, 64, and controls the deflection action by the optical axis deflection unit 35. The calculation control unit 28 also calculates the horizontal angle and vertical angle of the measurement point with respect to the reference optical axis O from the deflection angle and emission direction of the distance measurement light 49. Furthermore, the calculation control unit 28 can obtain three-dimensional data of the measurement point by relating the horizontal angle and vertical angle of the measurement point to the distance measurement data. Thus, the surveying device main body 3 functions as a total station.

[0073] Next, the attitude detector 36 will be described. The attitude detector 36 detects the inclination angle of the surveying instrument main body 3 relative to the horizontal or vertical, and the detection result is input to the calculation control unit 28. Note that a known attitude detector can be used as the attitude detector 36.

[0074] A brief description will be given of the attitude detector 36. The attitude detector 36 has a frame 66. The frame 66 is fixed to the housing 41 or to a structural member, and is integrated with the surveying device main body 3.

[0075] A sensor block 67 is attached via a gimbal to the frame 66. The sensor block 67 is rotatable 360° or more in two directions about two axes that are perpendicular to each other.

[0076] A first tilt sensor 68 and a second tilt sensor 69 are attached to the sensor block 67. The first tilt sensor 68 detects the horizontal with high precision and is, for example, a tilt detector that detects the horizontal from the change in the reflection angle of the reflected light when detection light is incident on the horizontal liquid surface, or a bubble tube that detects the tilt from the change in position of a sealed air bubble. The second tilt sensor 69 detects tilt changes with high responsiveness and is, for example, an acceleration sensor.

[0077] The relative rotation angles of the sensor block 67 with respect to the frame 66 about the two axes are detected by encoders 70 and 71, respectively.

[0078] In addition, motors (not shown) are provided for each of the two axes to rotate the sensor block 67 and maintain it horizontally. The motors are controlled by the calculation and control unit 28 based on the detection results from the first tilt sensor 68 and the second tilt sensor 69 so as to maintain the sensor block 67 horizontally.

[0079] When the sensor block 67 is tilted (when the surveying instrument body 3 is tilted), the relative rotation angle in each axial direction of the frame 66 with respect to the sensor block 67 (horizontal) is detected by the encoders 70 and 71. Based on the detection results of the encoders 70 and 71, the tilt angle about the two axes of the surveying instrument body 3 and the tilt direction are detected by combining the tilts of the two axes.

[0080] Since the sensor block 67 can rotate freely through 360° or more about two axes, it is possible to detect the attitude (angle of inclination and direction of inclination relative to the horizontal) in all directions no matter what attitude the attitude detector 36 is in, even if the attitude detector 36 is upside down, for example.

[0081] When high responsiveness is required in attitude detection, attitude detection and attitude control are performed based on the detection results of the second tilt sensor 69, but the second tilt sensor 69 generally has poorer detection accuracy than the first tilt sensor 68.

[0082] The attitude detector 36 is equipped with a high-precision first tilt sensor 68 and a highly responsive second tilt sensor 69, thereby enabling attitude control based on the detection results of the second tilt sensor 69, and further enabling highly accurate attitude detection by the first tilt sensor 68.

[0083] The detection result of the second tilt sensor 69 can be calibrated using the detection result of the first tilt sensor 68. In other words, if the relationship between the detected tilt angle of the second tilt sensor 69 and the tilt angle calculated based on the horizontal detection by the first tilt sensor 68 and the detection results of the encoders 70 and 71 is acquired in advance, the tilt angle detected by the second tilt sensor 69 can be calibrated, and the accuracy of the attitude detection with high responsiveness by the second tilt sensor 69 can be improved. In a state with little environmental change (temperature, etc.), the tilt detection may be calculated using the detection result of the second tilt sensor 69 and a correction value.

[0084] The calculation and control unit 28 controls the motor based on the signal from the second tilt sensor 69 when the variation in tilt is large or the change in tilt is fast. When the variation in tilt is small or the change in tilt is gradual, i.e., when the first tilt sensor 68 can follow, the calculation and control unit 28 controls the motor based on the signal from the first tilt sensor 68. Note that the tilt angle detected by the second tilt sensor 69 may be constantly calibrated so that the attitude detector 36 can detect the attitude based on the detection result from the second tilt sensor 69.

[0085] The memory unit 29 stores comparison data indicating a comparison result between the detection result of the first tilt sensor 68 and the detection result of the second tilt sensor 69. The detection result of the second tilt sensor 69 is calibrated based on the signal from the first tilt sensor 68. This calibration makes it possible to improve the detection accuracy of the second tilt sensor 69 to the detection accuracy of the first tilt sensor 68. Therefore, in the attitude detection by the attitude detector 36, high responsiveness can be achieved while maintaining high accuracy.

[0086] The attitude detector 36 detects in real time the attitude of the surveying instrument main body 3. Furthermore, since the attitude of the surveying instrument main body 3 can be detected in real time, the measurement values ​​can be corrected based on the results detected by the attitude detector 36. Therefore, leveling is not required when setting up the surveying instrument main body 3.

[0087] The measurement direction imaging section 37 has a first imaging optical axis 73 that has a predetermined relationship with the reference optical axis O of the surveying device main body 3, and an imaging lens 74 and an imaging element 75 that are arranged on the first imaging optical axis 73. The measurement direction imaging section 37 is a camera that has an angle of view of, for example, 50° to 60°, which is approximately equal to the maximum deviation angle θ / 2 (for example, ±30°) of the optical prisms 57, 58. The measurement direction imaging section 37 is capable of acquiring still images, continuous images, and moving images.

[0088] The relationship between the first imaging optical axis 73, the exit optical axis 44, and the reference optical axis O is known, the first imaging optical axis 73, the exit optical axis 44, and the reference optical axis O are parallel, and the distance between each optical axis is a known value.

[0089] The imaging control unit 31 controls the imaging of the measurement direction imaging unit 37. When the measurement direction imaging unit 37 captures a moving image or continuous images, the imaging control unit 31 synchronizes the timing of acquiring frame images constituting the moving image or continuous images with the timing of scanning and measuring distance by the surveying device main body 3. The calculation control unit 28 also executes association between the images and measurement data (distance measurement data, angle measurement data).

[0090] The imaging element 75 of the measurement direction imaging unit 37 is a CCD or CMOS sensor that is a collection of pixels, and the position of each pixel on the imaging element can be specified. For example, each pixel has pixel coordinates in a coordinate system with the first imaging optical axis 73 as the origin, and the position on the imaging element is specified by the pixel coordinates. In addition, since the relationship between the first imaging optical axis 73 and the reference optical axis O is known, it is possible to correlate the measurement position by the distance measuring unit 42 with the position on the imaging element 75. The image signal output from the imaging element 75 contains information on the pixel coordinates. The image signal is input to the image processing unit 32 via the imaging control unit 31.

[0091] The deflection and scanning actions of the optical axis deflection unit 35 will be described with reference to FIGS. FIG. 4 is a schematic diagram for explaining the function of the optical axis deflection unit of this embodiment. FIG. 5 is a schematic diagram illustrating an example of a scan pattern. FIG. 6 is a schematic diagram illustrating another example of the scan pattern.

[0092] 3 (when the orientations of the optical prisms 57 and 58 differ by 180° (relative rotation angle of 180°)), the mutual optical actions of the optical prisms 57 and 58 are offset, and the deviation angle is 0°. Therefore, the optical axis (distance measurement optical axis 53) of the laser beam emitted and received via the optical prisms 57 and 58 coincides with the reference optical axis O.

[0093] Moreover, when either one of the optical prisms 57, 58 is rotated 180° relative to the other from the state shown in FIG. 3 (the orientation of the prisms is in the same direction), the maximum deviation angle (for example, 30°) is obtained.

[0094] Therefore, the distance measurement optical axis 53 is deflected between 0° and 30° by the relative rotation between the optical prisms 57 and 58, and the deflection direction is changed by the integral rotation of the optical prisms 57 and 58.

[0095] Therefore, the distance measurement optical axis 53 can be deflected in any direction by controlling the relative rotation angle between the optical prisms 57 and 58 and the integral rotation angle of the optical prisms 57 and 58. In other words, the distance measurement optical axis 53 can be collimated to a measurement target in any direction.

[0096] Furthermore, by rotating the optical prisms 57 and 58 relative to each other or as a single unit while irradiating the distance measuring light 49, the distance measuring light 49 can be scanned in any direction and pattern.

[0097] 4, if the relative rotation angle between the optical prisms 57, 58 is θ and the distance measurement optical axis 53 is deflected by the optical prisms 57, 58 individually as deflections A and B, the actual deflection 76 is a composite deflection C, and the magnitude of the deflection angle is determined by the relative rotation angle θ. Therefore, when the optical prisms 57, 58 are synchronously rotated forward and backward at a constant speed, the distance measurement optical axis 53 (distance measurement light 49) is scanned linearly back and forth in the direction of the composite deflection C.

[0098] In addition, by individually controlling the rotation direction, rotation speed, and rotation speed ratio of the optical prism 57 and the optical prism 58, various two-dimensional scan patterns can be obtained by arranging the scanning trajectory of the distance measuring light 49 around the reference optical axis O.

[0099] For example, by setting the rotation ratio between the optical prism 57 and the optical prism 58 to 1:2, a two-dimensional closed loop scan pattern 77 in a figure-of-eight shape as shown in Fig. 5 can be obtained. The scan pattern 77 has an intersection point 78 where an outgoing path 79a and a return path 79b intersect. The intersection point 78 is the center of the scan pattern 77 and coincides with the reference optical axis O.

[0100] Furthermore, by rotating one optical prism 57 25 times and rotating the other optical prism 58 5 times in the opposite direction, a petal-shaped two-dimensional closed loop scan pattern 81 (petal pattern 81 (hypotrochoid curve)) is obtained as shown in Fig. 6. The petal pattern 81 also has an intersection point 82 at its center.

[0101] Furthermore, the maximum range in which two-dimensional scanning is possible with the surveying instrument main body 3 fixed is the maximum deflection angle range of the optical axis deflection unit 35 .

[0102] Next, the measurement operation of the survey system 1 according to this embodiment will be described. FIG. 7 is a schematic diagram illustrating the relationship between the scan pattern and the target device.

[0103] In preparation for starting measurement, the target device 5 is captured by the measurement direction imaging unit 37. Since the measurement direction imaging unit 37 has a wide angle of view of 50° to 60°, it is sufficient that the direction of the surveying device main body 3 is generally directed toward the target device 5. Furthermore, since the maximum deflection angle of the optical axis deflection unit 35 is the same as or approximately the same as the angle of view of the measurement direction imaging unit 37, capturing the target device 5 by the measurement direction imaging unit 37 means that the target device 5 is captured within a range that can be searched by the surveying device main body 3.

[0104] With the measurement direction imaging section 37 capturing the target device 5, the surveying device main body 3 searches for and aims at the measurement target. At this time, the surveying device main body 3 is in a fixed state.

[0105] Next, a two-dimensional search scan is executed by controlling the optical axis deflection unit 35, and in the two-dimensional search scan of this embodiment, an initial search scan with a wide search range and a local search scan limited to a narrow range including the measurement target are executed. Note that it is sufficient to execute a two-dimensional search scan, and it is not necessary to execute both the initial search scan and the local search scan. In the explanation of this embodiment, a case where both the initial search scan and the local search scan are executed is taken as an example.

[0106] In the following description, the figure-of-eight shaped scan pattern 77 (see FIG. 5) is adopted as the search scan pattern. Note that the petal shaped scan pattern 81 described above with reference to FIG. 6 may also be adopted as the search scan pattern.

[0107] First, an initial search scan is performed to detect the target device 5. The shape of the scan pattern 77 in the initial search scan at the start of the search is a horizontally flattened figure-8 shape, as shown in Fig. 7. At this time, the rotation speed of the figure-8 shaped scan pattern 77, i.e., the speed for one revolution, is, for example, about 10 Hz to 60 Hz. This range of rotation speed is also the same for a local scan pattern 77', which will be described later.

[0108] Since the linear reflecting portion 85 is long in the vertical direction, it is possible to perform a wide-range, high-speed search by flattening the scan pattern 77. Also, if the path of the scan pattern 77 of the initial search scan intersects with the linear reflecting portion 85, the reflected distance measuring light 52 from the linear reflecting portion 85 can be obtained, so there is no need to scan the entire search range without gaps, and it is sufficient to simply perform the same scan pattern continuously as shown in FIG.

[0109] The calculation control unit 28 controls the optical axis deflection unit 35 to execute an initial search scan, but since distance and angle measurement are also performed in addition to execution of the scan pattern 77, the deflection direction when the scan pattern crosses the linear reflector 85 is detected based on the reflected distance measurement light 52 from the linear reflector 85, and distance measurement is further performed up to the linear reflector 85. Therefore, the three-dimensional coordinates of the point where the scan pattern crosses the linear reflector 85 are obtained.

[0110] Furthermore, the calculation control unit 28 calculates the horizontal deflection angle and deflection direction of the point where the scan pattern crosses the linear reflecting unit 85 (hereinafter, the crossing point) with respect to the reference optical axis O. The horizontal angle between the crossing point and the center of the scan pattern (intersection point 78 in FIG. 7) is obtained, and the calculation control unit 28 controls the optical axis deflection unit 35 so that the scan pattern 77 moves in the direction in which the horizontal angle decreases.

[0111] In addition, when multiple reflected distance measuring lights 52 are obtained from the target device 5, measurements are made based on the light receiving signals obtained from the multiple reflected distance measuring lights 52, the obtained distance measuring results are averaged, and the optical axis deflection unit 35 is controlled based on the average value.

[0112] In parallel with the horizontal movement of the scan pattern 77, the scan pattern 77 is also moved up and down so that the scan pattern 77 detects the reference reflecting portion 84. Whether to move the scan pattern 77 downward or upward can be determined by detecting which position of the scan pattern 77 crosses the linear reflecting portion 85.

[0113] The arithmetic and control unit 28 moves the intersection 78 along the linear reflecting portion 85 until the reference reflecting portion 84 is detected by the scan pattern 77. Here, since the reference reflecting portion 84 protrudes in the radial direction from the linear reflecting portion 85, the reference reflecting portion 84 can be detected by a change in the distance measurement result. Fig. 7 shows the state in which the arithmetic and control unit 28 has detected the reference reflecting portion 84 by the scan pattern 77.

[0114] When the reference reflecting portion 84 is detected by the scan pattern 77, the scan pattern 77 is changed to a local scan pattern 77' suitable for detecting the center position of the reference reflecting portion 84. The local scan pattern 77' has a narrow search range and a vertically elongated shape.

[0115] When the intersection 78 of the local scan pattern 77' is near the center of the reference reflecting part 84, the local scan pattern 77' passes through the edge of the reference reflecting part 84. From the measurement result of the passing point of this edge, the position of the intersection 78 with respect to the reference reflecting part 84 can be measured, and the intersection 78 can be aligned with the center of the reference reflecting part 84.

[0116] When the intersection 78 coincides with the center of the reference reflector 84, the distance measurement optical axis 53 is collimated to the center of the reference reflector 84, and measurement of the reference reflector 84 is performed. Furthermore, from the relationship between the reference reflector 84 and the lower end of the pole 83, the three-dimensional coordinates of the measurement point P are calculated.

[0117] Furthermore, by executing local scan pattern 77', the three-dimensional coordinates of the upper and lower measurement points when local scan pattern 77' crosses linear reflecting portion 85 are measured. From the three-dimensional coordinates of the upper and lower measurement points, the tilt direction and tilt angle of pole 83 in the front-rear and left-right directions can be measured. In addition, the measurement result of measurement point P can be corrected based on the tilt direction and tilt angle of pole 83 and the relationship between reference reflecting portion 84 and the bottom end of pole 83.

[0118] Furthermore, the inclination of the pole 83 obtained here is an inclination with respect to the distance measurement optical axis 53, and the distance measurement optical axis 53 itself is not necessarily horizontal. The tilt angle and tilt direction of the distance measurement optical axis 53 with respect to the reference optical axis O can be measured by the emission direction detection unit 38. Furthermore, the tilt angle and tilt direction of the reference optical axis O with respect to the horizontal can be measured by the attitude detector 36.

[0119] Therefore, it is possible to measure the inclination angle and inclination direction of the pole 83 relative to the horizontal or vertical. By correcting the measurement result based on the inclination angle and inclination direction of the pole 83 relative to the horizontal or vertical, it is possible to accurately measure the distance, elevation angle, and horizontal angle for the accurate measurement point P (the point indicated by the bottom end of the pole 83) regardless of the inclination of the pole 83.

[0120] Therefore, even when measuring in a place where the target device 5 cannot be supported upright, such as a corner of a wall or a ceiling, accurate measurements can be performed if the measurement point can be indicated with the lower end of the pole 83 (or the upper end if measuring a ceiling).

[0121] When the measurement of the measurement point P is completed, the target device 5 is moved to the next measurement point to be measured.

[0122] When the target device 5 is moved to the next measurement point, the surveying device main body 3 continues to perform local scanning using the local scan pattern 77' while the target device 5 is moving, and tracks the reference reflector 84.

[0123] Next, tracking of the reference reflector 84 will be described in detail with reference to Figs. 8 to 12(c). FIG. 8 is a block diagram showing a schematic configuration of the arithmetic and control unit of this embodiment. FIG. 9 is a schematic diagram showing a first specific example of folding back and inverting the intensity distribution of a light receiving signal from a light receiving element. FIG. 10 is a schematic diagram showing a second specific example of folding back and inverting the intensity distribution of a light receiving signal from a light receiving element. FIG. 11 is a schematic diagram showing a third specific example in which the intensity distribution of a received light signal from a light receiving element is folded back and inverted. FIG. 12 is a schematic diagram showing a fourth specific example in which the intensity distribution of the light receiving signal from the light receiving element is folded back and inverted.

[0124] 8, the calculation control unit 28 of this embodiment has an accumulation cycle control counter 281, a weight calculation unit 282, an accumulation unit 283, and an output restriction unit 284. Every time the calculation control unit 28 detects a light receiving signal from the light receiving element 55 during execution of the local scan pattern 77', it updates the three-dimensional data of the measurement target (i.e., the reference reflector 84 and the linear reflector 85) based on the deviation data as the detection result by the emission direction detection unit 38 and the distance measurement data as the detection result by the distance measurement unit 42. A specific example of the tracking action of the surveying system 1 will be described below.

[0125] The integration cycle control counter 281 sets the number of pieces of data that can be acquired in one revolution of the scan pattern 77', i.e., the number of integrations, based on the light emission rate (Hz) of the light emitting element 45 and the rotation speed (Hz) of the scan pattern 77'. The integration cycle control counter 281 also counts up the addresses of the storage unit 29 in accordance with the number of integrations.

[0126] Each time the three-dimensional data is updated, weight calculation unit 282 generates weights for detecting a reference point and for detecting a rotation angle of the measurement object according to the distance from intersection 78. Specifically, each time the three-dimensional data is updated, weight calculation unit 282 generates weights for detecting a reference point of the measurement object such that the closer the distance from intersection 78 of scan pattern 77' is, the larger the weight. Also, each time the three-dimensional data is updated, weight calculation unit 282 generates weights for detecting a rotation angle of the measurement object such that the larger the distance from intersection 78 of scan pattern 77' is, the larger the weight.

[0127] Furthermore, the weight calculation unit 282 further generates correction data for use in detecting the rotation angle of the object to be measured, by folding back and inverting the intensity distribution of the light receiving signal from the light receiving element 55 on the orthogonal coordinate axes in the scan pattern 77'.

[0128] Specifically, since the measurement target has a rod-shaped linear reflecting portion 85 having a predetermined length in the vertical direction, the portions 851 and 852 of the received light signal having a high intensity appear approximately at the top and bottom as shown in Figs. 9(a), 10(a), 11(a) and 12(a). The portions 851 and 852 of the received light signal having a high intensity are portions of high reflection intensity when the local scan pattern 77' crosses the linear reflecting portion 85. Furthermore, since the measurement target has a reference reflecting portion 84 provided in the approximately center of the linear reflecting portion 85, the portion 781 of the received light signal having a high intensity appears between the upper portion 851 and the lower portion 852. The portion 781 of the received light signal having a high intensity is a portion of high reflection intensity when the local scan pattern 77' crosses the reference reflecting portion 84.

[0129] 9(a) to 12(c), the intensity of the received light signal from the light receiving element 55 is displayed as the diameter of a circle (i.e., a bubble). Therefore, the parts indicated by solid lines other than the parts 781, 851, and 852 where the received light signal has a high intensity are parts where the received light signal has a low intensity compared to the parts 781, 851, and 852.

[0130] Here, as described above, the weight calculation unit 282 generates weights for detecting the reference point and the rotation angle of the measurement object according to the distance from the intersection 78 each time the three-dimensional data is updated. Therefore, if the integrating unit 283 integrates the three-dimensional data of the measurement object as is, the intensities of the light receiving signals from the light receiving elements 55 may cancel each other out. For example, if the integrating unit 283 integrates the three-dimensional data of the measurement object as is, an upper part 851 where the intensity of the light receiving signal is strong and a lower part 852 where the intensity of the light receiving signal is strong may cancel each other out.

[0131] Therefore, the weight calculation unit 282 of this embodiment generates correction data by folding back and inverting the intensity distribution of the light receiving signal from the light receiving element 55 on the orthogonal coordinate axes in the scan pattern 77'.

[0132] For example, when the intensity distribution of the light receiving signal from the light receiving element 55 is the intensity distribution shown in FIG. 9(a), the weight calculation unit 282 folds back the intensity distribution below the x-axis of the orthogonal coordinate axes in the scan pattern 77' on the x-axis, as indicated by the arrow A11 shown in FIG. 9(a). The x-axis in this embodiment is an example of the "one coordinate axis" of the present invention, and is a horizontal axis passing through the intersection 78. The intensity distribution when the weight calculation unit 282 folds back the intensity distribution below the x-axis on the x-axis is as shown in FIG. 9(b). For convenience of explanation, the intensity distribution folded back on the x-axis is shown by a dashed line in FIG. 9(b).

[0133] Next, as shown by the arrow A12 in FIG. 9B, the weight calculation unit 282 further inverts only the intensity distribution folded over the x-axis around the y-axis. In the present specification, "invert" means to rotate 180° around any axis. The y-axis in this embodiment is an example of the "other coordinate axis" of the present invention, and is a vertical axis passing through the intersection 78. The intensity distribution when the weight calculation unit 282 further inverts only the intensity distribution folded over the x-axis around the y-axis is as shown in FIG. 9C. In this way, the weight calculation unit 282 generates first correction data for detecting the rotation angle of the measurement object. In this case, as shown by the solid arrow in FIG. 9C, even if the integration unit 283 integrates the three-dimensional data of the measurement object, the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong do not cancel each other out. According to this, the weight calculation unit 282 can prevent the upper part 851, where the intensity of the received light signal is strong, and the lower part 852, where the intensity of the received light signal is strong, from canceling each other out when the accumulating unit 283 accumulates the three-dimensional data of the object to be measured.

[0134] Also, for example, when the intensity distribution of the received light signal from the light receiving element 55 is the intensity distribution shown in Fig. 10(a), the weight calculation unit 282 folds back the intensity distribution on the left side of the y-axis on the y-axis, as indicated by the arrow A21 shown in Fig. 10(a). The intensity distribution shown in Fig. 10(a) is the same as the intensity distribution shown in Fig. 9(a). The intensity distribution when the weight calculation unit 282 folds back the intensity distribution on the left side of the y-axis on the y-axis is as shown in Fig. 10(b). For convenience of explanation, the intensity distribution folded back on the y-axis is shown by a dashed line in Fig. 10(b).

[0135] Next, as shown by the arrow A22 in FIG. 10(b), the weight calculation unit 282 further inverts only the intensity distribution folded over the y axis around the x axis. The intensity distribution when the weight calculation unit 282 further inverts only the intensity distribution folded over the y axis around the x axis is as shown in FIG. 10(c). In this way, the weight calculation unit 282 generates second correction data for detecting the rotation angle of the measurement object. In this case, as shown by the dashed arrow in FIG. 10(c), when the integrating unit 283 integrates the three-dimensional data of the measurement object, the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong cancel each other out. Therefore, in this case, the weight calculation unit 282 selects the first correction data of the first and second correction data for detecting the rotation angle of the measurement object.

[0136] Furthermore, when the intensity distribution of the light receiving signal from the light receiving element 55 is the intensity distribution shown in Fig. 11(a), the weight calculation unit 282 folds back the intensity distribution below the x-axis on the x-axis as indicated by the arrow A31 shown in Fig. 11(a). The intensity distribution when the weight calculation unit 282 folds back the intensity distribution below the x-axis on the x-axis is as shown in Fig. 11(b). For ease of explanation, the intensity distribution folded back on the x-axis is shown by a dashed line in Fig. 11(b).

[0137] Next, as shown by the arrow A32 in FIG. 11B, the weight calculation unit 282 further inverts only the intensity distribution folded over the x-axis around the y-axis. The intensity distribution when the weight calculation unit 282 further inverts only the intensity distribution folded over the x-axis around the y-axis is as shown in FIG. 11C. In this way, the weight calculation unit 282 generates the first correction data for detecting the rotation angle of the measurement object. In this case, as shown by the solid arrow in FIG. 11C, even if the integrating unit 283 integrates the three-dimensional data of the measurement object, the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong do not cancel each other out. According to this, the weight calculation unit 282 can prevent the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong from canceling each other out when the integrating unit 283 integrates the three-dimensional data of the measurement object.

[0138] Also, for example, when the intensity distribution of the light receiving signal from the light receiving element 55 is the intensity distribution shown in Fig. 12(a), the weight calculation unit 282 folds back the intensity distribution on the left side of the y-axis on the y-axis as indicated by the arrow A41 shown in Fig. 12(a). The intensity distribution shown in Fig. 12(a) is the same as the intensity distribution shown in Fig. 11(a). The intensity distribution when the weight calculation unit 282 folds back the intensity distribution on the left side of the y-axis on the y-axis is as shown in Fig. 12(b). For convenience of explanation, the intensity distribution folded back on the y-axis is shown by a dashed line in Fig. 12(b).

[0139] Next, as shown by the arrow A42 in FIG. 12(b), the weight calculation unit 282 further inverts only the intensity distribution folded over the y-axis around the x-axis. The intensity distribution when the weight calculation unit 282 further inverts only the intensity distribution folded over the y-axis around the x-axis is as shown in FIG. 12(c). In this way, the weight calculation unit 282 generates second correction data for detecting the rotation angle of the measurement object. In this case, as shown by the solid arrow in FIG. 12(c), even if the integrating unit 283 integrates the three-dimensional data of the measurement object, the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong do not cancel each other out. According to this, the weight calculation unit 282 can prevent the upper part 851 where the intensity of the received light signal is strong and the lower part 852 where the intensity of the received light signal is strong from canceling each other out when the integrating unit 283 integrates the three-dimensional data of the measurement object. In this case, the weight calculation section 282 selects at least one of the first correction data and the second correction data for use in detecting the rotation angle of the object to be measured.

[0140] The integrating unit 283 calculates the position of the reference point (i.e., the center of the reference reflecting unit 84) and the rotation angle of the measurement object, using the weighting for detecting the reference point and the weighting for detecting the rotation angle generated by the weighting calculation unit 282. The integrating unit 283 also calculates the rotation angle of the measurement object, using the weighting for detecting the rotation angle generated by the weighting calculation unit 282 according to the distance from the intersection, and at least one of the first correction data and the second correction data (see Figs. 9(a) to 12(c)) generated by the weighting calculation unit 282.

[0141] Furthermore, the integrating unit 283 discards the oldest three-dimensional data every time it detects a light receiving signal from the light receiving element 55 during execution of the local scan pattern 77', i.e., every time it acquires new three-dimensional data, and accumulates the acquired new three-dimensional data and stores it in the storage unit 29. This allows the integrating unit 283 to simplify the amount of calculation and the content of calculation required for each measurement point, and shorten the time required for calculation processing. Then, the calculation control unit 28 performs tracking of the reference reflector 84 based on the position of the reference point (i.e., the center of the reference reflector 84) and the rotation angle of the measurement target calculated by the integrating unit 283.

[0142] The output limiting unit 284 limits the amount of change when the amount of change or the rate of change of the reference point position and the rotation angle of the measurement target calculated by the integrating unit 283 is greater than a predetermined value. For example, when the amount of change of the reference point position of the measurement target calculated by the integrating unit 283 is greater than a predetermined amount of change, the output limiting unit 284 limits the movement range within the scan area. In addition, when the rate of change of the rotation angle is greater than a predetermined value, or when the difference between the weight of the reference point of the measurement target and the weight of the outer periphery point of the measurement target is greater than a predetermined value, the output limiting unit 284 determines that the outer periphery part of the scan pattern 77' does not capture the target device 5. Then, the surveying device main body 3 executes the above-mentioned search. By executing control related to such restrictions, the output limiting unit 284 can suppress unnecessary control of the motors 63, 64 from being executed.

[0143] According to the surveying system 1 of this embodiment, the calculation control unit 28 controls the deflection by the optical axis deflection unit 35, executes a two-dimensional scan with the distance measurement light 49 approximately centered on the distance measurement optical axis 53, and controls the two-dimensional scan with scan patterns 77, 77', 81 having intersections 78, 82 at which the forward and backward paths of the two-dimensional scan intersect. Then, every time the calculation control unit 28 detects a light receiving signal during the two-dimensional scan, it updates the three-dimensional data of the measurement target based on the declination data as the detection result by the emission direction detection unit 38 and the distance measurement data as the detection result by the distance measurement unit 42. In this way, the calculation control unit 28 acquires and updates the three-dimensional data every time it detects a light receiving signal during the two-dimensional scan, so that it is possible to track the measurement target at high speed even if a predetermined amount of three-dimensional data is not accumulated. At this time, the calculation control unit 28 generates weights for detecting the reference point and the rotation angle of the measurement target according to the distance from the intersections 78, 82 of the scan patterns 77, 77', 81 every time the three-dimensional data is updated, and tracks the measurement target based on the reference point position and the rotation angle of the measurement target calculated using the weights. Therefore, even when the calculation control unit 28 acquires and updates three-dimensional data every time a light receiving signal is detected during two-dimensional scanning, it is possible to shorten the time required for calculation processing and track the measurement target at high speed. As a result, the surveying system 1 according to this embodiment is able to prevent the measurement target from being lost and to track the measurement target more reliably.

[0144] In addition, the calculation control unit 28 generates weighting for detecting the reference point of the measurement object so that the closer the distance from the intersections 78, 82 of the scan patterns 77, 77', 81 is, the larger the weighting value becomes, so that the reference point of the measurement object can be detected with higher accuracy. As a result, the surveying system 1 according to this embodiment can track the measurement object more reliably.

[0145] Furthermore, the calculation control unit 28 generates weighting for detecting the rotation angle of the measurement target so that the value increases as the distance from the intersections 78 and 82 of the scan patterns 77, 77', and 81 increases, so that the rotation angle of the measurement target can be detected with higher accuracy. As a result, the surveying system 1 according to this embodiment can track the measurement target more reliably.

[0146] The arithmetic control unit 28 further generates first correction data for detecting the rotation angle of the measurement object by folding back the intensity distribution of the received light signal on one of the orthogonal coordinate axes in the two-dimensional scan (x-axis in this embodiment). The arithmetic control unit 28 further generates second correction data for detecting the rotation angle of the measurement object by folding back the intensity distribution of the received light signal on the other of the orthogonal coordinate axes in the two-dimensional scan (y-axis in this embodiment). The arithmetic control unit 28 then tracks the measurement object based on the rotation angle of the measurement object calculated using the weighting for detecting the rotation angle generated according to the distance from the intersections 78 and 82 of the scan patterns 77, 77', and 81, and at least one of the first correction data and the second correction data. Therefore, even when the arithmetic control unit 28 generates the weighting for detecting the reference point and the weighting for detecting the rotation angle of the measurement object according to the distance from the intersections 78 and 82 of the scan patterns 77, 77', and 81, it is possible to prevent the intensity distributions of the received light signals from canceling each other out. This allows the survey system 1 according to this embodiment to more reliably track the measurement target.

[0147] The calculation control unit 28 also generates first correction data by folding back the intensity distribution of the received light signal on one coordinate axis (x-axis in this embodiment) and then further inverting only the intensity distribution folded back on one coordinate axis (x-axis in this embodiment) around the other coordinate axis (y-axis in this embodiment). The calculation control unit 28 also generates second correction data by folding back the intensity distribution of the received light signal on the other coordinate axis (y-axis in this embodiment) and then further inverting only the intensity distribution folded back on the other coordinate axis (y-axis in this embodiment) around one coordinate axis (x-axis in this embodiment). Therefore, even if the measurement target does not extend in the vertical and horizontal directions (see FIG. 11(a) and FIG. 12(a)), that is, even if the measurement target is inclined with respect to the vertical and horizontal directions, it is possible to prevent the intensity distributions of the received light signals from canceling each other out. As a result, the surveying system 1 according to this embodiment can more reliably track the measurement target.

[0148] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the claims. The configurations of the above embodiments can be partially omitted or arbitrarily combined differently from the above. For example, in this embodiment, the surveying device main body 3 is used as a total station, but it may also be used as a laser scanner. [Explanation of symbols]

[0149] 1: Surveying system, 2: Tripod, 3: Surveying device main body, 4: Installation stand, 5: Target device, 6: Terminal device, 11: Base unit, 12: Horizontal rotation shaft, 13: Horizontal angle detector, 14: Horizontal rotation gear, 15: Horizontal pinion gear, 16: Horizontal motor, 17: Vertical rotation shaft, 18: Vertical rotation gear, 19: Pinion gear, 21: Vertical motor, 22: Vertical angle detector, 25: Distance measurement light emitting unit, 26: Light receiving unit, 27: Distance measurement calculation unit, 28: Calculation control unit, 29: Memory unit, 31: Imaging control unit, 32: Image processing unit, 33: Communication unit, 35: Optical axis deflection unit, 36: Attitude detector, 37: Measurement direction imaging unit, 38: Emission direction detection unit, 39: Motor driver, 41: Housing, 42: distance measuring section, 44: emission optical axis, 45: light emitting element, 46: light projecting lens, 47: first reflecting mirror, 48: second reflecting mirror, 49: distance measuring light, 51: light receiving optical axis, 52: reflected distance measuring light, 53: distance measuring optical axis, 54: imaging lens, 55: light receiving element, 57, 58: optical prism, 59, 60: ring gear, 61, 62: driving gear, 63, 64: motor, 66: frame, 67: sensor block, 68: first tilt sensor, 69: second tilt sensor, 70, 71: encoder, 73: first imaging optical axis, 74: imaging lens, 75: imaging element, 76: deflection, 77, 77': scan pattern, 78: intersection, 79a: outward path, 79b: return path, 81: scan pattern, 82: intersection, 83: pole, 84: reference reflector, 85: linear reflector, 180: relative rotation angle, 281: integration period control counter, 282: weight calculation unit, 283: integration unit, 284: output limiter, 781, 851, 852: part, A, B: deflection, C: composite deflection, O: reference optical axis, P: measurement point

Claims

1. A measurement target having a retroreflector; a measuring device main body that emits distance measuring light and measures the measurement target based on the distance measuring light reflected from the retroreflector; A surveying system comprising: The measuring device body includes: a distance measurement light emitting unit having a light emitting element that emits the distance measurement light and that emits the distance measurement light onto a distance measurement optical axis; a light receiving section having a light receiving element that receives the reflected distance measuring light and generates a light receiving signal; a distance measuring unit that measures the distance to the measurement object based on the light receiving signal from the light receiving element; an optical axis deflection unit having a reference optical axis and deflecting the distance measurement optical axis with respect to the reference optical axis; an emission direction detection unit that detects a deviation angle and a direction of the deviation angle of the distance measurement optical axis with respect to the reference optical axis; an arithmetic and control unit for controlling the deflection action of the optical axis deflection unit and the distance measurement action of the distance measurement unit; having The surveying system is characterized in that the calculation control unit controls the two-dimensional scan with a scan pattern having an intersection where the forward and backward paths of the two-dimensional scan intersect, updates the three-dimensional data of the measurement object based on the declination data as the detection result by the emission direction detection unit and the distance measurement data as the detection result by the distance measurement unit each time the light receiving signal is detected during the two-dimensional scan, generates weighting for detecting the reference point and the rotation angle of the measurement object in accordance with the distance from the intersection each time the three-dimensional data is updated, and tracks the measurement object based on the reference point position and rotation angle of the measurement object calculated using the weighting.

2. 2. The surveying system according to claim 1, wherein the calculation control unit generates the weighting for detecting the reference point so that the closer the distance from the intersection, the larger the weighting value.

3. 3. The surveying system according to claim 1, wherein the calculation control unit generates the weighting for detecting the rotation angle so that the weighting value increases as the distance from the intersection increases.

4. The surveying system according to any one of claims 1 to 3, characterized in that the calculation control unit further generates first correction data obtained by folding back the intensity distribution of the received light signal on one of the orthogonal coordinate axes in the two-dimensional scan, and second correction data obtained by folding back the intensity distribution of the received light signal on the other of the orthogonal coordinate axes, for use in detecting the rotation angle of the object to be measured, and tracks the object to be measured based on the rotation angle calculated using the weighting for detecting the rotation angle generated according to the distance from the intersection, and at least one of the first correction data and the second correction data.

5. The surveying system according to claim 4, characterized in that the calculation control unit generates the first correction data by folding back the intensity distribution of the received light signal on one coordinate axis, and then further inverting only the intensity distribution folded back on the one coordinate axis around the other coordinate axis, and generates the second correction data by folding back the intensity distribution of the received light signal on the other coordinate axis, and then further inverting only the intensity distribution folded back on the other coordinate axis around the one coordinate axis.

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