JP7224833B2 - Distance measurement device and position calculation system - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act (1) Announced in the publication "The Institute of Image Information and Television Engineers 2018 Annual Conference Proceedings" published on August 15, 2018 by the Institute of Image Information and Television Engineers ( 2) Announced on August 31, 2018 at the ITE 2018 Annual Conference held by the Institute of Image Information and Television Engineers from August 29 to 31, 2018.

The present invention relates to a distance measuring device that measures a distance to an object to be measured, and a position calculation system that calculates the position of the object to be measured from the measured distance.

2. Description of the Related Art Conventionally, in program production and movie production, it has been widely practiced to synthesize CG or another image with an image captured by a camera while it is moving. In order to generate the camera data of the photographic camera when synthesizing, a method of measuring the position of the photographic camera has been proposed (for example, see Patent Document 1). The method described in Patent Literature 1 is to keep the tension of a wire tied to a photographing camera constant, measure the length and direction of the wire, and determine the position of the photographing camera based on the measured length and direction.

Japanese Patent Application Laid-Open No. 2013-92441 (Patent No. 5941261)

However, the conventional technique described above has a problem that the measurement result is easily affected by the vibration and bending of the wire, and the accuracy is low.

Accordingly, an object of the present invention is to provide a highly accurate distance measuring device and a position calculating system.

In view of the above-described problems, a distance measuring device according to the present invention is a distance measuring device for measuring the distance between a moving measurement object and a preset measurement reference object, wherein The attached sensor mounting member, the laser sensor attached to the sensor mounting member, and the string-like body arranged on the measurement reference object and connected to the sensor mounting member maintain tension as the measurement object moves. A winding/unwinding mechanism for winding and unwinding a string-like body, and a laser reflector having an insertion hole through which the string-like body is inserted and attached to the winding/unwinding mechanism via a second follower. , the laser reflector and the laser sensor are maintained facing each other, the laser sensor irradiates the laser reflector with laser light, and the distance is measured by the reflected light from the laser reflector.

According to such a distance measuring device, when the object to be measured moves, the sensor mounting member attached via the first driven portion also moves. Further, in the distance measuring device, the string-like body connected to the sensor mounting member is wound or unwound by a winding/unwinding mechanism arranged on a predetermined measurement reference object through the insertion hole of the laser reflector. be done. In the distance measuring device, since the wound or unwound string-like body maintains tension, the laser sensor and the reflective surface always maintain a posture facing each other even if the object to be measured moves. Therefore, the distance measuring device can always measure the distance even if the positional relationship between the measurement object and the measurement reference object changes due to the movement of the measurement object. At this time, since the distance measuring device uses a laser sensor to measure the distance, the measurement result is less susceptible to the shaking and bending of the string-shaped body.

In view of the above-described problems, a position calculation system according to the present invention includes a first distance measuring device and a second distance measuring device, which are the distance measuring devices according to the present invention, and an object to be measured which is supported at a predetermined position. The configuration includes a support arm to be moved, a support mechanism having a support leg for supporting the support arm, an elevation angle measurement sensor for measuring the elevation angle of the support arm, and a position calculation device.

According to such a position calculation system, the position calculation device uses a trigonometric function to calculate the height of the object to be measured from the preset length of the arm, the height of the tripod, and the elevation angle of the arm measured by the elevation angle measurement sensor. By point surveying, the plane position of the object to be measured is calculated from the distances calculated by the first distance measuring device and the second distance measuring device.

As described above, the first distance measuring device and the second distance measuring device can always measure the distance even if the positional relationship between the measurement object and the measurement reference object changes due to the movement of the measurement object. At this time, since the first distance measuring device and the second distance measuring device use laser sensors for distance measurement, the measurement results are less likely to be affected by the shaking and bending of the string-shaped body.

Note that the position calculation system may include a height measurement sensor that measures the height of the object to be measured instead of the elevation angle measurement sensor.
Also, the position calculation system may be provided with a total of three sets of distance measurement devices by adding one set of distance measurement devices instead of the elevation angle measurement sensor and the height measurement sensor.

ADVANTAGE OF THE INVENTION According to this invention, there exists the following outstanding effects.
According to the present invention, even if the positional relationship between the measurement object and the measurement reference object changes due to movement of the measurement object, the distance can always be measured. Furthermore, according to the present invention, since a laser sensor is used to measure the distance, the measurement result is less susceptible to the shaking and bending of the string-like body, and accuracy can be improved.

1 is a side view of a distance measuring device according to a first embodiment; FIG. 2 is an enlarged view of the laser sensor device of FIG. 1; FIG. It is an enlarged view of the wire winding and unwinding device of FIG. 1, (a) is a front view, (b) is a side view. FIG. 4 is an explanatory diagram illustrating postures of a laser sensor and a laser reflector in the first embodiment; It is a side view of the position calculation system which concerns on 2nd Embodiment. It is a block diagram which shows the structure of the position calculation apparatus which concerns on 2nd Embodiment. FIG. 11 is an explanatory diagram illustrating a method of calculating the height of a photographing camera in the second embodiment; FIG. 11 is an explanatory diagram illustrating a method of calculating a plane position of a photographing camera by triangulation in the second embodiment; 9 is a flow chart showing the operation of the position calculation system according to the second embodiment; It is a side view of the position calculation system which concerns on 3rd Embodiment. FIG. 11 is a block diagram showing the configuration of a position calculation device according to a third embodiment; FIG. It is a flow chart which shows operation of a position calculation system concerning a 3rd embodiment. It is a side view of the position calculation system which concerns on a modification.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. It should be noted that the drawings referred to in the following description are schematic representations of the embodiments, and therefore the scales, intervals, positional relationships, etc. of each member are exaggerated, or illustration of some of the members is omitted. Sometimes. Further, in the following description, the same names and symbols basically indicate the same or homogeneous members, and the detailed description will be omitted as appropriate. Furthermore, the directions shown in the figures indicate relative positions between components and are not intended to indicate absolute positions.

(First embodiment)
[Overview of distance measuring device]
An outline of a distance measuring device 1 according to the first embodiment will be described with reference to FIG.
As shown in FIG. 1, the distance measuring device 1 uses a laser sensor device 10 attached to a photographic camera (measurement target) T to measure the distance between the photographic camera T and a measurement reference position (measurement reference target) A. It is.
In each drawing, the horizontal direction is the X axis, the vertical direction is the Y axis, and the depth direction is the Z axis. Also, in FIG. 1, the laser beam emitted by the laser sensor device 10 is illustrated by a broken line.

The measurement reference position A is a reference position for measuring the distance, and is a position where the wire winding/unwinding device 20 described later is arranged. For example, the measurement reference position A can be set at an arbitrary position on the floor of the photography studio.

The photographing camera T is a general camera for photographing images such as television programs, and is mounted on a tripod Ta that can be moved in the photographing studio, for example. A cameraman takes a picture while moving a camera T mounted on a tripod Ta back and forth and right and left. Also, the cameraman can extend and retract the tripod Ta to move the photographing camera T up and down.

Here, as the photographing camera T moves, the positional relationship between the laser sensor device 10 attached to the photographing camera T and the measurement reference position A changes. On the other hand, it is preferable that the laser sensor device 10 faces the measurement reference position A in order for the laser sensor device 10 to measure the distance with high accuracy. Therefore, the distance measuring device 1 keeps the tension of the wire (string-like body) 30 tied to the laser sensor device 10 constant, thereby mechanically causing the orientation of the laser sensor device 10 to follow the measurement reference position A. bottom.

[Configuration of distance measuring device]
The configuration of the distance measuring device 1 will be described below.
The distance measuring device 1 includes a laser sensor device 10 , a wire winding/unwinding device 20 and a wire 30 .

<Laser sensor device>
The laser sensor device 10 measures the distance between the photographing camera T and the measurement reference position A. As shown in FIG. This laser sensor device 10 includes a plate 11 , a universal joint (first driven portion) 12 , a disk member (sensor mounting member) 13 , and a laser sensor 14 .

The plate 11 is a flat plate member on which the photographing camera T is placed. This plate 11 has a photographing camera T mounted on its upper surface and a universal joint 12 attached to the end of its lower surface. For example, an aluminum flat plate can be used as the plate 11 .
Note that the laser sensor device 10 may directly attach the universal joint 12 to the photographing camera T without using the plate 11 .

The universal joint 12 is a universal joint that faces in any direction. As shown in FIG. 2, the universal joint 12 includes a T-shaped portion 120, a joint 121, and a fixing member 122 so that the angle connecting the photographing camera T and the measurement reference position A can be freely changed.
The T-shaped portion 120 has a fixed shaft 120a having one end fixed to the center of the back surface of the disk member 13, and an arm portion 120b provided so as to be perpendicular to the other end of the fixed shaft 120a. The T-shaped portion 120 is rotatably supported through the first branched portion 121a of the joint 121 at both ends of the arm portion 120b. As a result, the T-shaped portion 120 is rotatable about the arm portion 120b so as to follow the arm portion 120b in one axial direction within a predetermined angle range.

The joint 121 has a U-shaped first branched portion 121a, a barrel portion 121b provided at the first branched portion 121a, and a second branched portion 121c provided at the other end of the barrel portion 121b. . Also, the joint 121 has orthogonal directions in which the first branched portion 121a and the second branched portion 121c are attached to the trunk shaft portion 121b. The second branch portion 121c of the joint 121 is rotatably supported by a projecting portion 121d penetrating through the clamping portion 122a of the fixing member 122 in the Z-axis direction.
As a result, the joint 121 is rotatable in the axial direction perpendicular to the T-shaped portion 120, with the projecting portion 121d as an axis, so as to be driven within a predetermined angle range.
The fixing member 122 has a disk portion 122b fixed to the lower surface of the plate 11, and a holding portion 122a provided parallel to and spaced from the disk portion 122b. The joint 121 is attached to the fixing member 122 so as to follow the clamping portion 122a within a predetermined angle range.
Needless to say, the universal joint 12 is not limited to the structure shown in FIG.

The disk member 13 connects the tip of the wire 30 to the center of the surface, and attaches (fixes) the laser sensor 14 in the vicinity of the wire 30 . Also, the disk member 13 is attached to the photographing camera T (more precisely, the plate 11) via the universal joint 12. As shown in FIG.
In the universal joint 12, the wire 30 can be attached/detached from the disk member 13 by engaging an engagement hook provided at the tip of the wire 30 and an engagement ring provided at the center of the surface of the disk member 13. (not shown).

The laser sensor 14 is a general ranging sensor that measures distance using laser light. The laser sensor 14 irradiates a laser reflector 23 to be described later with a laser beam, and measures the distance between the photographing camera T and the measurement reference position A by the reflected light from the laser reflector 23 .

With the above configuration, the laser sensor device 10 can maintain a posture in which the laser reflector 23 and the laser sensor 14 face each other when the wire 30 is pulled and tension is maintained.

<Wire winding/unwinding device>
The wire winding/unwinding device 20 winds and unwinds the wire 30, and includes a winding/unwinding mechanism 21, a universal joint (second driven portion) 22, and a laser reflector 23. Prepare.

The winding/unwinding mechanism 21 keeps the wire 30 connected to the disk member 13 at a constant tension, and winds and unwinds the wire 30 as the photographing camera T moves. The winding/unwinding mechanism 21 is arranged at the measurement reference position A in advance. As shown in FIG. 3, the winding/unwinding mechanism 21 includes a housing 210, a bearing 211a, a bearing 211b, a rotating shaft 212a, a rotating shaft 212b, a support rod 213, a constant tension spring 214, A first pulley 215 , a second pulley 216 and a base 217 are provided.

The housing 210 has a substantially rectangular parallelepiped shape, and a partition plate 210a is provided in a partial region within the rectangular parallelepiped in order to dispose the universal joint 22, which will be described later. The partition plate 210 a has a through hole 210 b for allowing the wire 30 to reach the first pulley 215 inside the housing 210 . Further, the housing 210 is provided with a bearing 211a in the central portion of the side surface to support the rotating shaft 212a. Further, the housing 210 has a bearing 211b that passes through the partition plate 210a in the Z-axis direction, and supports the rotating shaft 212b with the bearing 211b. Further, the housing 210 fixes the support rod 213 of the constant tension spring 214 at the same height as the rotation shaft 212a on the right side of the side surface.

The constant-tension spring 214 is a figure-8 leaf spring wound around the rotating shaft 212 a and the support rod 213 . That is, the constant tension spring 214 is housed inside the housing 210, has both ends connected to the rotating shaft 212a and the support rod 213, and applies tension to the wire 30 in the winding direction of the rotating shaft 212a. Also, the constant tension spring 214 is arranged so as to be adjacent to the first pulley 215 on the rotating shaft 212a. Here, the constant tension spring 214 is provided with discs on both ends in the Z-axis direction, and since these discs contact the side plates of the first pulley 215, movement in the Z-axis direction on the rotation shaft 212a is restricted.
The first pulley 215 is a pulley for winding and unwinding the wire 30 . The first pulley 215 is housed inside the housing 210 and supported by a rotating shaft 212a so that the rotating surface of the second pulley 216 and the second pulley 216 are on the same plane.
The second pulley 216 is a pulley for guiding the wire 30 from the outside of the housing 210 to the first pulley 215 . The second pulley 216 is supported by a rotary shaft 212b so as to be aligned with the first pulley 215 in the X-axis direction.
The base 217 is a base portion that contacts the imaging floor. The base 217 is two parallel plates provided on the lower surface of the housing 210 .

The universal joint 22 is a universal joint that faces in any direction. As shown in FIG. 3, the universal joint 22 is arranged on the partition plate 210a. Further, the universal joint 22 includes a T-shaped portion 220 and a joint 221 so that the angle connecting the photographing camera T and the measurement reference position A can be freely changed.
The T-shaped portion 220 is formed so as to face an insertion hole 231 of the laser reflecting plate 23, which will be described later, so that the wire 30 can be inserted therethrough. This T-shaped portion 220 has a structure similar to that of the T-shaped portion 120 in FIG.
The joint 221 is connected to the T-shaped portion 220 and formed so that the wire 30 is inserted therethrough. This joint 221 is formed in a cylindrical shape so that the wire 30 can be inserted therethrough, and the rear end side is supported by a rotating shaft 212b. Also, the joint 221 is arranged so as to be aligned with the second pulley 216 in the X-axis direction. As a result, the wire 30 inserted inside the joint 221 is guided by the second pulley 216 toward the through hole 210 b and is wound up or unwound by the first pulley 215 . Otherwise, joint 221 is of similar construction to joint 121 of FIG.

The laser reflector 23 reflects laser light. For example, the laser reflecting plate 23 may have a reflecting surface 230 that reflects laser light coated or mirror-finished. Further, the laser reflector 23 is provided with an insertion hole 231 in the plate thickness direction at the center of the reflecting surface 230 so that the wire 30 can be inserted therethrough. This laser reflecting plate 23 is attached to the winding/unwinding mechanism 21 via the universal joint 22 in the same manner as the disk member 13 .

With the above configuration, the wire winding/unwinding device 20 can maintain a posture in which the laser reflector 23 and the laser sensor 14 face each other when the wire 30 is pulled and tension is maintained.

<Wire>
The wire 30 is a string-like material that connects the photographing camera T and the wire winding/unwinding device 20 . One end of the wire 30 is connected to the photographing camera T (more precisely, the disk member 13). Further, the wire 30 is wound by the winding/unwinding mechanism 21 or unwound from the winding/unwinding mechanism 21 as the photographing camera T moves.

[Action/effect]
In the distance measuring device 1, as shown in FIG. 4, when the photographing camera T moves from the position indicated by the broken line to the position indicated by the solid line, the disk member 13 attached via the universal joint 12 also moves. In the distance measuring device 1, the wire 30 connected to the disk member 13 is passed through the insertion hole 231 (FIG. 3) of the laser reflector 23 by the winding/unwinding mechanism 21 arranged at the measurement reference position A. rolled up or unrolled. In the distance measuring device 1, the winding/unwinding mechanism 21 maintains the tension of the wire 30 wound or unwound. Maintain an upright posture. Therefore, even if the positional relationship between the photographing camera T and the measurement reference position A changes due to the movement of the photographing camera T, the distance measuring device 1 can always measure the distance. At this time, since the distance measurement device 1 uses the laser sensor 14 to measure the distance, the measurement result is less likely to be affected by the shaking or bending of the wire 30, and the accuracy can be improved.

Here, advantages of the distance measuring device 1 when compared with existing methods for measuring the photographing camera T will be briefly described.
The existing method of measuring with a special pedestal with wheels has the problem of accumulating errors when the wheels slide on the floor of the photography studio. In addition, existing methods using infrared sensors placed on the ceiling have problems such as interference with lighting installed on the ceiling and expensive equipment. Furthermore, the existing method of measuring by image analysis using a stereo camera requires a lot of work in advance calibration, and there are problems such as occlusion caused by obstacles blocking the shooting camera. Compared to these existing methods, the distance measuring device 1 does not require the introduction of dedicated equipment, and can be introduced at a low cost by simply modifying existing equipment. By introducing this distance measuring device 1, it becomes possible to construct a virtual studio at a low cost and expand the range of video expression.

(Second embodiment)
[Configuration of position calculation system]
The configuration of the position calculation system 100 according to the second embodiment will be described with reference to FIG.
The position calculation system 100 uses two sets of the distance measurement device _1A and the distance measurement device _1B to measure the distance in two directions, and calculates the spatial position of the photographing camera T based on the principle of triangulation (triangulation). It is something to do. As shown in FIG. 5 , the position calculation system 100 includes a distance measurement device 1 _A and a distance measurement device 1 _B , a crane (support mechanism) 40 , an elevation angle measurement sensor 50 and a position calculation device 60 .

A distance measuring device (first distance measuring device) _1A includes a laser sensor device _10A , a wire winding/unwinding device _20A , and a wire _30A . Further, the distance measuring device (second distance measuring device) 1-- _B includes a laser sensor device 10-- _B , a wire winding/unwinding device 20-- _B , and a wire 30-- _B .
The laser sensor device 10- _A and the laser sensor device 10- _B are attached to the same photographing camera T. As shown in FIG. Then, the laser sensor device _10A and the laser sensor device _10B transmit the respective measured distances to the position calculation device 60 by wireless communication or wired communication.
Further, since the wire winding/unwinding device _20A is arranged at the measurement reference position A and the wire winding/unwinding device _20B is arranged at the measurement reference position B, the measurement reference position A and the measurement reference position B are different.
Other points, the distance measuring device _1A and the distance measuring device _1B , are the same as those in the first embodiment, so further explanation is omitted.

In FIG. 5, the laser sensor device _10A and the laser sensor device _10B are shown separated from each other to make the drawing easier to see, but it is preferable to attach them close to each other to reduce measurement errors. For example, the laser sensor device 10- _A and the laser sensor device 10- _B are attached so as to line up in the Z-axis direction in front of the lower surface of the plate 11 (FIG. 8). Also, since the distance between the laser sensor devices _10A and _10B is much shorter than the distance measured by each, the distance is ignored.

The crane 40 supports and moves the photographic camera T to a desired position, and includes an arm (support arm) 41 and a tripod (support leg) 42 . In this embodiment, the crane 40 is set on the floor of the photography studio.
The arm 41 moves the photographing camera T to a predetermined position. Also, the arm 41 has a photographing camera T mounted on one end thereof so as to keep it horizontal, and is supported by a tripod 42 on the rear end side of the center. By changing the length and direction of the arm 41, the photographing camera T can be moved to a desired position.
A tripod 42 supports the arm 41 . For example, the tripod 42 is a stationary tripod that supports the rear end side of the arm 41 . Note that the tripod 42 is not limited to a stationary tripod, and may be a mobile tripod that can move back and forth and left and right on the floor surface of the photography studio (not shown).

The elevation angle measurement sensor 50 is a rotation angle sensor (for example, a rotary encoder) attached to the rotation shaft of the arm 41 and measuring the elevation angle of the arm 41 . That is, the elevation angle measurement sensor 50 measures the angle of the arm 41 with respect to the floor surface (horizontal plane) of the photography studio. Then, the elevation angle measurement sensor 50 transmits the measured elevation angle of the arm 41 to the position calculation device 60 by wireless communication or wired communication.

[Configuration of position calculation device]
The configuration of the position calculation device 60 will be described with reference to FIG.
The position calculation device 60 calculates the spatial position of the photographing camera T, and is arranged behind the photographing camera T, for example. As shown in FIG. 6 , the position calculation device 60 includes height calculation means 61 , planar position calculation means 62 , and spatial position output means 63 .

The height calculation means 61 calculates the height of the photographing camera T from the preset length L of the arm 41, the height _H0 of the tripod 42, and the elevation angle θ of the arm 41 received from the elevation angle measurement sensor 50, using a trigonometric function. H is calculated. Then, the height calculation means 61 outputs the calculated height H of the photographing camera T to the planar position calculation means 62 and the spatial position output means 63 .
The plane position calculation means 62 calculates the plane position of the photographing camera T from the distance D _A and _{the distance D B received} from the distance measurement devices _1A and 1B by triangulation. Then, the planar position calculation means 62 outputs the calculated planar position of the photographing camera T to the spatial position output means 63 .
The spatial position output means 63 uses the height H of the photographic camera T input from the height calculation means 61 and the planar position of the photographic camera T input from the planar position calculation means 62 as the spatial position of the photographic camera T. This is the output.

<Calculation of spatial position>
Calculation of the spatial position of the photographing camera T will be specifically described with reference to FIGS. 7 and 8. FIG.
First, the length L of the arm 41 and the height _H0 of the tripod 42 are preset as parameters in the height calculation means 61 . As shown in FIG. 5, the length L of the arm 41 represents the length from the tip of the arm 41 to the rotation axis to which the elevation angle measurement sensor 50 is attached. Also, the height _H0 of the tripod 42 represents the height from the floor surface of the photography studio to the rotation axis to which the elevation angle measurement sensor 50 is attached.

As shown in FIG. 7, the height calculation means 61 uses the following equation (1) to calculate the photographing angle from the length L of the arm 41, the height _H0 of the tripod 42, and the elevation angle θ of the arm 41. A height H of the camera T is calculated.
H=L sin θ+H ₀ Expression (1)

Next, the planar position calculating means 62 calculates the irradiation angle φ _A of the laser sensor 14 _A using an inverse trigonometric function in order to obtain the horizontal component of the distance D _A . Here, the irradiation angle φ _A represents the angle of the laser beam irradiated by the laser sensor _14A with respect to the floor surface (horizontal surface) of the photography studio. Specifically, the planar position calculation means 62 calculates the irradiation angle φ _A from the height H of the photographing camera T and the distance _DA using the following equation (2).
φ _A = arcsin (H/D _A ) Equation (2)

Next, since the distance _DA measured by the distance measuring device 1A also includes a height component, the planar position calculation means 62 uses a trigonometric function to calculate the horizontal distance DA _' , which is the horizontal component of the distance _DA . calculate. Specifically, the plane position _calculation means 62 calculates the horizontal distance D A ′ from the distance D _A and the illumination angle φ _A using the following equation (3).
D _A '=D _A cos φ _A Expression (3)

Note that the planar position calculation means 62 calculates the irradiation angle φ _B by the formula (2) in the same manner as the irradiation angle φ _A , and calculates the horizontal distance D _B ' by the formula (3) as well as the horizontal distance D _A '. (not shown in FIG. 7).

As shown in FIG. 8, the distance D _AB between the measurement reference position A and the measurement reference position B is preset as a parameter in the planar position calculation means 62 . This distance D _AB can be measured in advance when the wire winding/unwinding device _20A and the wire winding/unwinding device _20B are installed. Then, the planar position calculating means 62 calculates the position of the photographing camera T on the floor surface of the photographing studio from the distances of the photographing camera T, the measurement reference position A, and the measurement reference position B by triangulation. That is, the planar position calculation means 62 calculates the planar position of the photographing camera T from the lengths of the three sides of the horizontal distance D _A ', the horizontal distance D _B ', and the distance D _AB by triangulation.

7 and 8, for the sake of simplicity of explanation, the sizes and mounting positions of the universal joint 12, the laser sensor 14, and the laser reflector 23 are ignored. These may be reflected in order to calculate the spatial position.

[Operation of position calculation system]
The operation of the position calculation system 100 will be described with reference to FIG.
As shown in FIG. 9, in the position calculation system 100, as parameters, the length L of the arm 41, the height H ₀ of the tripod 42, and the distance D _AB are set in advance (step S1).

The laser sensor _14A measures the distance _DA between the photographing camera T and the measurement reference position A. Also, the laser sensor _14B measures the distance D _B between the photographing camera T and the measurement reference position B (step S2). Although the distance D _A and the distance D _B are measured simultaneously in step S2, either the distance D _A or the distance D _B may be measured first.
The elevation angle measurement sensor 50 measures the elevation angle θ of the arm 41 (step S3).

The height calculation means 61 calculates the height H of the photographing camera T from the length L of the arm 41 and the height _H0 of the tripod 42 set in step S1 and the elevation angle θ of the arm 41 measured in step S3. do. Specifically, the height calculation means 61 calculates the height H of the photographing camera T using the formula (1) (step S4).

The planar position calculation means 62 calculates the planar position of the photographing camera T from the distance D _A and the distance D _B measured in step S2. Specifically, the plane position calculation means 62 calculates the irradiation angle φ _A and the irradiation angle φ _B using the above equation (2). Then, the plane position calculation means 62 calculates the horizontal distance D _A ' and the horizontal distance D _B ' using the above equation (3). Further, the plane position calculation means 62 calculates the plane position of the photographing camera T from the lengths of the three sides of the horizontal distance D _A ', the horizontal distance D _B ', and the distance D _AB using trilateration (step S5).

The spatial position output means 63 outputs the height H of the photographing camera T calculated in step S4 and the planar position of the photographing camera T calculated in step S5 as the spatial position of the photographing camera T (step S6).

[Action/effect]
As described above, the position calculation system 100 according to the present embodiment uses the distance measurement device _1A and the distance measurement device _1B , which are less susceptible to shaking and bending of the wire 30, so accuracy can be improved. Furthermore, the position calculation system 100 does not require the introduction of dedicated equipment, as in the first embodiment, and can be introduced at a low cost by simply modifying existing equipment.

(Third embodiment)
[Configuration of position calculation system]
With reference to FIG. 10, the configuration of the position calculation system 100A according to the third embodiment will be described with respect to the differences from the second embodiment.
The position calculation system 100 of FIG. 5 obtains the height H of the photographing camera T from the elevation angle θ measured by the elevation angle measurement sensor 50 . On the other hand, the position calculation system 100A of FIG. 10 differs in that the height measurement sensor 70 measures the height H of the photographing camera T. FIG.

As shown in FIG. 10, the position calculation system 100A includes a distance measurement device _1A and a distance measurement device _1B , a crane (support mechanism) 40A, a height measurement sensor 70, and a position calculation device 80. Since the distance measuring device _1A and the distance measuring device _1B are the same as those in the second embodiment, description thereof is omitted.

The crane 40A supports the photographing camera T and moves it to a desired position, and includes an arm 41 and a tripod 42A. That is, the crane 40A does not have the elevation angle measurement sensor 50 of FIG.
The tripod 42A has wheels and is a mobile tripod that can move forward, backward, leftward, and rightward on the floor surface of the photography studio. Note that the tripod 42A is not limited to a mobile tripod, and may be a stationary tripod (not shown).
Other points of the crane 40A are the same as those of the second embodiment, so further description is omitted.

The height measurement sensor 70 is a sensor that measures the height H of the photographing camera T, and may be fixed to the center of the lower surface of the plate 11 . For example, as the height measurement sensor 70, a general ranging sensor such as a laser sensor, an infrared sensor, an ultrasonic sensor, etc. can be used. Then, the height measurement sensor 70 transmits the measured height H of the photographing camera T to the position calculation device 80 by wireless communication or wired communication.

[Configuration of position calculation device]
The configuration of the position calculation device 80 will be described with reference to FIG. 11 .
The position calculation device 80 calculates the position of the photographing camera T, and includes planar position calculation means 81 and spatial position output means 82 as shown in FIG.

The plane position calculation means 81 calculates the plane position of the photographing camera T by triangulation from the distance D _A and the distance D _B received from the distance measurement devices _{1A and 1B} . Here, since the planar position calculation means 81 receives the height H of the photographing camera T from the height measurement sensor 70, it is not necessary to calculate the height H of the photographing camera T. FIG.
Other points, the plane position calculation means 81, are the same as those in the second embodiment, so further explanation will be omitted.

The spatial position output means 82 outputs the height H of the photographing camera T received from the height measurement sensor 70 and the plane position of the photographing camera T inputted from the plane position calculation means 81 as the spatial position of the photographing camera T. It is something to do.

[Operation of position calculation system]
The operation of the position calculation system 100A will be described with reference to FIG.
As shown in FIG. 12, the position calculation system 100A presets the distance _DAB as a parameter (step S10).

The laser sensor _14A measures the distance _DA between the photographing camera T and the measurement reference position A. Also, the laser sensor _14B measures the distance D _B between the photographing camera T and the measurement reference position B (step S11). Note that the process of step S11 is the same as the process of step S2 in FIG.
The height measurement sensor 70 measures the height H of the photographing camera T (step S12).

The planar position calculation means 62 calculates the planar position of the photographing camera T from the distance D _A and the distance D _B measured in step S11 (step S13). It is the same.
The spatial position output means 63 outputs the height H of the photographing camera T measured in step S12 and the planar position of the photographing camera T calculated in step S13 as the spatial position of the photographing camera T (step S14).

[Action/effect]
As described above, the position calculation system 100A according to this embodiment can improve the accuracy as in the second embodiment. Furthermore, the position calculation system 100A, like the second embodiment, does not require the introduction of dedicated equipment, and can be introduced at a low cost by simply modifying existing equipment.

(Modification)
Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and includes design changes and the like within the scope of the present invention.
In the second and third embodiments described above, the spatial position of the photographing camera is calculated by trilateration, but the method of trilateration is not limited to this.
In the second embodiment and the third embodiment described above, the position calculation device is arranged behind the photographing camera, but the arrangement position is not limited to this.

In each of the above-described embodiments, the photographic camera is mounted on a tripod, but the present invention is not limited to this. For example, the photographing camera may be a general shoulder-mounted camera that is placed on the shoulder of the photographer to photograph.
In each of the above-described embodiments, the object to be measured is a camera, but the object is not limited to this.

In each of the above-described embodiments, the winding/unwinding mechanism uses a constant tension spring, but the invention is not limited to this. The winding/unwinding mechanism may be any mechanism capable of winding and unwinding the wire while maintaining the tension of the wire.
In each of the above-described embodiments, the string-like body is a wire, but it is not limited to this. The string-like body may be any string-like material that can maintain tension between the measurement target and the winding/unwinding mechanism. For example, string-like bodies may include threads, ropes, and chains.

In each of the above-described embodiments, the first driven portion and the second driven portion have been described as universal joints, but the present invention is not limited to this. The first driven part and the second driven part may be anything as long as they can move the laser sensor in any direction. For example, the first driven portion and the second driven portion may be ball joints or flexible joints.

In the second and third embodiments described above, the position calculation system is provided with two sets of distance measurement devices, and the elevation angle measurement sensor and the height measurement sensor are used in combination. However, the present invention is not limited to this. As shown in FIG. 13, the position calculation system 100B adds a set of distance measurement devices (third distance measurement device) _1C instead of the elevation angle measurement sensor and the height measurement sensor, so that a total of three sets of distance measurement devices are added. 1 _A to 1 _C may be provided. In this case, the distance measuring devices 1 _A to 1 _C are attached to the same photographing camera T. FIG. On the other hand, the measurement reference positions A to C of the distance measuring devices 1 _A to 1 _C are different from each other. Accordingly, the position calculation system 100B (position calculation device 90) can calculate the spatial position of the photographing camera T from the distances measured by the distance measurement devices _1A to _1C by triangulation.

The present invention can be used in television program production and movie production. In particular, the present invention makes it possible to perform processes such as synthesizing computer graphics with video in a virtual studio program, a drama program, or a sports broadcast, with high accuracy and efficiency.
In addition, the present invention can be used for measurement of various operating devices, wheelchairs for physically handicapped persons, and mobile robots.

1 Distance measuring device 1 _A distance measuring device (first distance measuring device)
1 _B distance measuring device (second distance measuring device)
1 _C distance measuring device (third distance measuring device)
10 laser sensor device 11 plate 12 universal joint (first driven part)
13 Disk member (sensor mounting member)
14, _14A , _14B laser sensor 20, _20A , _20B , _20C wire winding/unwinding device 21 winding/unwinding mechanism 22 universal joint (second driven part)
23 laser reflector 30 wire (string-like body)
40, 40A crane (support mechanism)
41 arm (support arm)
42, 42A tripod (support leg)
50 elevation angle measurement sensor 60 position calculation device 61 height calculation means 62 plane position calculation means 63 spatial position output means 70 height measurement sensor 80 position calculation device 81 plane position calculation means 82 spatial position output means 90 position calculation devices 100, 100A, 100B, 100C Position calculation system T Shooting camera (measurement target)
A, B, C Measurement reference position (measurement reference target)

Claims (6)

A distance measuring device for measuring the distance between a moving measurement object and a preset measurement reference object,
a sensor attachment member attached to the measurement object via a first driven portion;
a laser sensor attached to the sensor attachment member;
Winding/winding for winding and unwinding the string-like body as the measurement target moves so that the string-like body placed on the measurement reference object and connected to the sensor mounting member maintains tension. an exit mechanism;
a laser reflector having an insertion hole through which the string-shaped body is inserted and attached to the winding/unwinding mechanism via a second driven part;
Maintaining a posture in which the laser reflector and the laser sensor face each other,
A distance measuring device, wherein the laser sensor irradiates the laser reflector with a laser beam and measures the distance by the reflected light from the laser reflector. 2. The distance measuring device according to claim 1, wherein the first driven portion and the second driven portion are universal joints in which an angle connecting the measurement object and the measurement reference object can be freely changed. The second driven part is
a T-shaped portion formed facing the insertion hole of the laser reflector and through which the string-like body is inserted;
a joint connected to the T-shaped portion and through which the string-shaped body is inserted;
The T-shaped portion is uniaxially driven within a predetermined angle range,
3. The distance measuring device according to claim 2, wherein the joint is driven within a predetermined angle range in an axial direction perpendicular to the T-shaped portion. A first distance measuring device and a second distance measuring device, which are the distance measuring devices according to any one of claims 1 to 3;
a support mechanism having a support arm that supports and moves a measurement target to a predetermined position, and a support leg that supports the support arm;
an elevation angle measurement sensor that measures the elevation angle of the support arm;
Using a trigonometric function, the height of the object to be measured is calculated from the preset length of the support arm, the height of the support leg, and the elevation angle of the support arm measured by the elevation angle measurement sensor. a position calculation device that calculates the planar position of the measurement target from the distances calculated by the first distance measurement device and the second distance measurement device,
The first distance measuring device and the second distance measuring device are attached to the same measurement object, and the first distance measuring device and the second distance measuring device are arranged on different measurement reference objects. A position calculation system characterized by: A first distance measuring device and a second distance measuring device, which are the distance measuring devices according to any one of claims 1 to 3;
a height measurement sensor that measures the height of the object to be measured;
A position calculation device that calculates the planar position of the measurement target from the distances calculated by the first distance measurement device and the second distance measurement device by three-point survey,
The first distance measuring device and the second distance measuring device are attached to the same measurement object, and the first distance measuring device and the second distance measuring device are arranged on different measurement reference objects. A position calculation system characterized by: A first distance measuring device, a second distance measuring device, and a third distance measuring device, which are the distance measuring devices according to any one of claims 1 to 3;
A position calculation device that calculates the spatial position of the measurement target from the distances calculated by the first distance measurement device, the second distance measurement device, and the third distance measurement device by three-point survey,
The first distance measuring device, the second distance measuring device, and the third distance measuring device are attached to the same measurement object, and the first distance measuring device, the second distance measuring device, and the third distance measuring device A position calculation system characterized in that the devices are arranged on measurement reference targets different from each other.

Images