Measuring device

Abstract

To provide a measuring device capable of maintaining analysis accuracy by correctly acquiring measurement data from a sensor mounted inside even when an attitude in a pipe changes.SOLUTION: A measuring device 1 is inserted into a pipeline to measure the position of the pipeline, and includes an inner housing 3 holding an inertial sensor 32 therein, and an outer housing 2 holding the inner housing 3 therein. The inside housing 3 is supported by the outside housing 2 so as to be turnable around a shaft 31 along the conduit direction, and includes an energizing part for energizing force for maintaining a posture in the turning direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a measurement device. [Background technology]

[0002] When identifying the route of underground pipelines such as power pipelines, communication pipelines, water pipes, and gas pipes, the route is sometimes measured using a measuring device that moves inside the pipeline. The measuring device is equipped with a camera, a gyro sensor, an acceleration sensor, etc., and the route of the pipeline is identified by determining the moving position from data acquired from these sensors. For example, Patent Document 1 discloses a measuring device that measures the state of bending inside the pipeline by inserting a detector consisting of a gyro and an accelerometer housed in a waterproof bag into the pipe and pulling it up. Furthermore, Patent Document 2 discloses an inspection system that inspects pipes by moving a sensor head in the longitudinal direction of the pipe by winding or feeding out a cable connected to the sensor head, which includes an ultrasonic sensor and an imaging device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-201069 [Patent Document 2] Japanese Patent Publication No. 2023-78544 Summary of the Invention [Problem to be solved by the invention]

[0004] When measuring the path, the measuring device moves inside the pipe, and as the device moves, it may come into contact with the inner wall of the pipe, or pass over steps inside the pipe, causing the position of the measuring device to change. This change in position changes the orientation of the sensor installed inside, resulting in incorrect measurement data and affecting the accuracy of analysis.

[0005] The present invention has been made based on this background, and aims to provide a measuring device that can correctly acquire measurement data from an internal sensor and maintain analysis accuracy even when the position inside the pipe changes. [Means for solving the problem]

[0006] In order to achieve the above object, a measuring device according to the present invention comprises: A measuring device that is inserted into a pipeline and measures the position of the pipeline, an inner housing that holds the inertial sensor therein; an outer housing that holds the inner housing therein; The inner housing is supported by the outer housing so as to be rotatable about an axis extending in the pipe direction, and includes a biasing portion that applies a force to maintain an attitude in the rotation direction. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a measuring device that can correctly acquire measurement data from an internally mounted sensor and maintain analysis accuracy even when its posture within a pipe changes. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are schematic diagrams showing an example of the configuration of a measurement device according to an embodiment of the present invention, in which FIG. 1A is a cross-sectional view seen from the side, and FIG. 1B is a cross-sectional view seen from the front. [Figure 2] 1A is a cross-sectional view of another example of the configuration of a measuring device according to an embodiment of the present invention, as viewed from the side, and FIG. 1B is a cross-sectional view of yet another example of the configuration of a measuring device according to an embodiment of the present invention, as viewed from the side. [Figure 3] FIG. 2 is a diagram showing an example of an electrical configuration of a measurement device according to an embodiment of the present invention. [Figure 4] 1 is a diagram illustrating measurement of a pipe path using a measurement device according to an embodiment of the present invention. [Figure 5]1. FIG. 4 is a cross-sectional view seen from the front of an example in which the arrangement of components mounted inside the measuring device of FIG. 1 is changed. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a measuring device according to an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same or equivalent parts are designated by the same reference numerals.

[0010] The measuring device 1 is inserted into an underground electric power pipe or other pipe and measures its position as it moves through the pipe to determine the pipe's location. The measuring device 1 incorporates various inertial sensors, which will be described later. As shown in FIG. 1, the measuring device 1 has a cylindrical outer housing 2. The diameter of the cylinder is determined to be large enough to pass through the pipe, depending on the inner diameter of the pipe to be measured. However, if the diameter of the cylinder is too small compared to the inner diameter of the pipe, the measuring device 1 will move around in the pipe when inserted and removed, resulting in significant changes in its position and posture. Therefore, the diameter of the cylinder is set to be close to the inner diameter of the pipe. FIG. 1 shows an example of a measuring device 1 with a diameter large enough to pass through a standard pipe with a minimum diameter of 50 mm.

[0011] A connecting portion 5 for connecting the wire 4 to the measuring device 1 is provided at one longitudinal end of the outer housing 2. The connecting portion 5 is composed of a connecting ring 51 attached to the outer housing 2 and a connecting fitting 52 attached to the connecting ring 51. The connecting fitting 52 is composed of a ring-shaped snap hook made up of a hook portion and an openable / closable opening / closing portion. The tip of the wire 4 is provided with a ring portion, which is connected to the snap hook through the openable / closable portion. This makes the measuring device 1 detachable from the wire 4. The wire 4 connected to the measuring device 1 moves the measuring device 1 within the pipeline by pulling up the measuring device 1 inserted into the pipeline. Note that the snap hook may be attached to the wire instead of the measuring device 1. Furthermore, the wire may be connected to the measuring device 1 with a carabiner instead of the snap hook.

[0012] A cylindrical inner housing 3 is provided inside the outer housing 2. The inner housing 3 has an axis 31 that runs longitudinally through the center of the circle. When the measuring device 1 is inserted into a pipeline, the axis 31 is oriented along the pipeline direction. Both ends of the axis 31 are supported by bearings 21 provided in the outer housing, and the inner housing 3 is journaled relative to the outer housing 2 so that it can rotate in the circumferential direction. In this way, the housing of the measuring device 1 has a double structure, with an axis and bearing provided in its center, and a mechanism is provided in which the inner housing 3 does not rotate even if the outer housing 2 rotates when the measuring device 1 is moved.

[0013] An inertial sensor 32, a single-board computer 33, a battery 34, and a weight 35 are provided inside the inner housing 3. The inertial sensor 32 is an inertial measurement unit (IMU) that has an angular velocity (gyro) sensor and an acceleration sensor and acquires inertial information. The inertial sensor 32 may consist of only an angular velocity sensor or only an acceleration sensor. The single-board computer 33 is a small computing device that includes a processor, a wireless communication module, a memory, etc. and executes various processes. The battery 34 supplies power to the inertial sensor 32 and the single-board computer 33.

[0014] The inertial sensor 32, single-board computer 33, and battery 34 are arranged near the axis 31 and parallel to the axis 31. The single-board computer 33 is provided in a position close to and above the axis 31, the battery 34 is provided in a position close to and below the axis 31, and the inertial sensor 32 is arranged above the single-board computer 33. By arranging each component close to the axis 31, it is possible to prevent the components from significantly shifting the center of gravity within the inner housing 3. The inertial sensor 32, single-board computer 33, and battery 34 are attached, for example, to a mounting base (not shown) extending from the inner wall of the inner housing 3. The order in which they are arranged is not limited to the above, but it is preferable to place the heavier components at the bottom.

[0015] The inner housing 3, which is rotatably attached to the outer housing 2, has a weight 35 as a biasing unit that applies a force to maintain its orientation in the rotational direction around the X-axis. The weight 35 is attached to the inner wall surface so that the center of gravity of the inner housing 3 is eccentric from the axis, and biases it in the direction of gravity by its own weight. Therefore, the inner housing 3 maintains its orientation so that the position where the weight 35 is attached is maintained below the axis 31. When the outer housing 2 is moved left and right around its center as indicated by the solid arrow, the inner housing 3 moves around the axis 31 in the direction opposite to the movement direction of the outer housing 2, as indicated by the dotted arrow. When the orientation of the inner housing 3 in the rotational direction is maintained by the weight 35, the inertial sensor 32 is arranged within the inner housing 3 so as to be maintained in a direction perpendicular to the direction of gravity.

[0016] Next, as another example of the measuring device 1, a measuring device 1 having a diameter large enough to pass through a pipe with a diameter larger than 50Φ is shown. As shown in FIG. 2, (a) shows a measuring device 1 having a diameter large enough to pass through a pipe with a diameter of 80Φ, and (b) shows a measuring device 1 having a diameter large enough to pass through a pipe with a diameter larger than 80Φ. This differs from FIG. 1 in that, in addition to the inertial sensor 32, an ultrasonic sensor 36 and a camera 37 are provided as sensors for measuring the inside of the pipe. The larger diameter allows for more sensors to be installed internally. A camera 37 for capturing images of the inside of the pipe, an LED (Light Emitting Diode) 38 for illumination, and an ultrasonic sensor 36 are provided on the outer wall of the inner housing 3 in the longitudinal direction opposite the side where the swivel is provided. Furthermore, the wall of the outer housing 2 facing the outer wall of the inner housing 3 on which the camera 37, LED 38, and ultrasonic sensor 36 are provided is made of a transparent filter 22. The camera 37 captures still and video images to confirm the conditions inside the pipe. The LED 38 is a light that illuminates the inside of the pipe so that the camera 37 can photograph the inside of the pipe, and irradiates the illuminating light into the pipe through the transparent filter 22. The camera 37 photographs the situation inside the pipe as observed through the transparent filter 22. The ultrasonic sensor 36 is a distance measuring sensor that can measure the distance to an obstacle without contact by emitting ultrasonic waves and measuring the reflection time it takes for the generated ultrasonic waves to reflect off the obstacle and return. The ultrasonic sensor 36 emits ultrasonic waves to the end of the pipe, which acts as an obstacle, and is used to constantly grasp the distance from the measuring device 1 to the end of the pipe.

[0017] Furthermore, for measuring devices 1 having a diameter that can pass through a pipe larger than 80Φ, an adapter 23 that matches the diameter of the pipe is provided, as shown in Figure 2(b). By fitting and attaching adapter 23 to the outer periphery of the outer casing 2 of measuring device 1 having a diameter that can pass through a pipe with a diameter of 80Φ as shown in Figure 2(a), a measuring device 1 that matches the required diameter is formed. By making adapter 23 detachable from measuring device 1 having a diameter that can pass through an 80Φ pipe and preparing multiple adapters 23 with different diameters, it becomes possible to measure pipes of multiple diameters.

[0018] Next, the electrical configuration of the measuring device 1 shown in Figure 2 will be described. As shown in Figure 3, the measuring device 1 includes a processor 331 that controls the entire device, a ROM (Read Only Memory) 333 that is a non-volatile storage circuit, a RAM (Random Access Memory) 334 that is a volatile storage circuit, a memory unit 335, a wireless communication module 332 that performs wireless communication, an input control circuit 336 that controls input via a power switch 39, an acceleration sensor 322 that detects acceleration, a gyro sensor 321 that detects angular velocity, an LED 38 for illumination, a camera 37, an ultrasonic sensor 36, and a battery 34 such as a secondary battery that supplies power to the above circuits. The acceleration sensor 322 and the gyro sensor 321 constitute an inertial sensor 32. The processor 331, the ROM 333, the RAM 334, the memory unit 335, the wireless communication module 332, and the input control circuit 336 constitute a single-board computer 33. The power switch 39 is a switch that supplies power from the battery 34 to each component of the measuring device 1.

[0019] The acceleration sensor 322 and gyro sensor 321, which are inertial sensor 32, measure the position of measuring device 1, i.e., the pipeline position. The acceleration sensor 322 is a three-axis acceleration sensor that detects acceleration in three mutually orthogonal axis directions, thereby measuring changes in the operating speed of measuring device 1 while it is moving within the pipeline.

[0020] The gyro sensor 321 is a three-axis angular velocity sensor that measures changes in the direction of movement of the measuring device 1 while it is moving within the pipeline by detecting the angular velocity of rotation around each of the three axes that define the acceleration in the acceleration sensor 322.

[0021] The camera 37 is, for example, a CMOS (Complementary Metal Oxide Semiconductor) camera, a CCD (Charge Coupled Device) camera, or the like, and is operated from the outside to take wide-angle images of the inside of the pipeline toward the end of the pipeline. The captured image signal is processed by the single-board computer 33 or the like, stored in the storage unit 335, and transmitted to the external device 6.

[0022] The ultrasonic sensor 36 emits an ultrasonic pulse toward the end of the pipeline when an external trigger pulse is input. When the ultrasonic pulse hits the end of the pipeline, it is reflected, and the ultrasonic sensor 36 receives this reflected signal. The received signal is processed by the single-board computer 33 or the like to calculate the distance from the end of the pipeline. Note that the ultrasonic sensor 36 is just one example, and other distance measuring sensors such as a laser sensor may also be used.

[0023] The processor 331 is connected to each circuit via a bus, and executes a control program stored in the ROM 333 to realize various functions and control the entire device.

[0024] The ROM 333 stores a control program and various fixed data used by the processor 331 to control the entire device. The RAM 334 functions as a work area for the processor 331. The storage unit 335 is a non-volatile memory such as a flash memory. The storage unit 335 stores programs used by the processor 331 to perform various processes and data generated or acquired by the various processes. By executing a predetermined control program, the processor 331 controls the measurement operations of the acceleration sensor 322 and the gyro sensor 321, the saving and reading of sensor data to the RAM 334 and the storage unit 335, and the transmission of inertial data to the external device 6 via the wireless communication module 332.

[0025] The wireless communication module 332 has an interface for communicating with the external device 6 via close proximity wireless communication such as wireless LAN (Local Area Network) or Bluetooth (registered trademark), and communicates wirelessly with the external device 6 via an antenna (not shown). The inertial data acquired by the measuring device 1 is transmitted to the external device 6 via the wireless communication module 332.

[0026] The input control circuit 336 converts the signal input from the power switch 39 into data and transmits it to the processor 331 , and also controls various measurements based on control signals from the processor 331 .

[0027] The external device 6 transmits operation signals to the measuring device 1 to instruct the measuring device 1 to perform various operations, which will be described later. The external device 6 also receives inertial data, image data, and ranging data transmitted from the measuring device 1 via the wireless communication module 332. The external device 6 analyzes the received inertial data and the like and displays the analysis results. The external device 6 is, for example, a smartphone, a tablet terminal, a personal computer, etc.

[0028] An operation program that instructs the measurement device 1 to perform various operations is stored in the external device 6, and operations are performed on the measurement device 1 via an operation screen displayed on the display unit of the external device 6. For example, the operation screen displays the following operation menu, and when the measurement device 1 is started up, the operator presses each button on the operation menu to execute the program. (1) Sensor information graph display Angular velocity data obtained by the gyro sensor 321 and acceleration data obtained by the acceleration sensor 322 are received in real time from the measuring device 1, and the received angular velocity data and acceleration data are processed and displayed as a graph on the screen. This allows the angular velocity and acceleration occurring in the measuring device 1 to be visually grasped. (2) Inertial sensor measurement Angular velocity data obtained from the gyro sensor 321 and acceleration data obtained from the acceleration sensor are received in real time from the measuring device 1, and the received angular velocity data and acceleration data are processed in chronological order at predetermined time intervals to output attitude angle data of roll (φ) and pitch (θ) and save it as a file. (3) Camera photography During measurement inside the pipe, in order to check the condition inside the pipe in real time, the camera 37 in the measuring device is remotely controlled by the external device 6 to take pictures of the inside of the pipe. (4) Distance measurement and camera photography When measuring the distance from the measuring device 1 to the end of a pipeline, an ultrasonic sensor 36 and a camera 37 are used in combination so that the position from the end of the pipeline can be visually grasped. The camera 37 takes images of the inside of the pipeline at predetermined time intervals, and at the same time, the ultrasonic sensor 36 measures the distance to the end of the pipeline. The captured image data is added with data on the distance to the end of the pipeline at the time of capture and saved as a file. Here, as an example of adding distance data, the file name of the image data can be the measured distance. (5) Sending emails The created files of each measurement data are sent by e-mail to a pre-registered address.

[0029] Next, we will explain an example of measuring the path of a pipeline using the measuring device 1. As shown in Fig. 4, a pipeline 41 to be measured extends along the inner wall of a manhole 40. An electric winch 42 is provided inside the manhole 40 to pull up the wire 4 connecting the measuring device 1 from the pipeline 41.

[0030] During measurement, the length of the pipeline 41 to be measured and the conditions inside the pipeline 41 are roughly confirmed by the pipeline camera 43, and confirmation is made as to whether measurement is possible using the measuring device 1, how long the wire 4 is required, and how fast the wire 4 should be pulled up. The pipeline camera 43 has a structure in which a camera head is attached to the tip of a flexible rod, for example, and is operated by a worker 44 from the ground to insert the camera head into the pipeline 41 from the inner wall of the manhole 40, and then push the rod into the pipeline 41 to move the camera head forward, thereby photographing the inside of the pipeline 41.

[0031] When a power switch 39 provided on the measuring device 1 is turned on, power is supplied from a battery 34 to each component within the device. When the power is turned on, the measuring device 1 is waterproofed by covering it with a heat-shrinkable tube to prevent water from entering the housing during measurement, for example, through an opening provided for operating the power switch 39.

[0032] Once waterproofing has been performed, the measuring device 1 is connected to the wire 4 via a snap hook and is removably attached to the tip of the pipe camera 43. Alternatively, the measuring device 1 is not attached to the tip of the pipe camera 43, but is first inserted into the pipe 41. The pipe camera 43 is then inserted into the pipe 41, and the measuring device 1 is pushed in, moving the measuring device 1 to the pipe end 45, which is the measurement start position. When the measuring device 1 reaches the pipe end 45, the pipe camera 43 is retrieved from the inside of the pipe 41 by winding up the rod, leaving only the measuring device 1 behind.

[0033] When the measuring device 1 is placed at the pipe end 45, which is the measurement start position, and preparations for measurement are complete, measurement of the path of the pipe 41 begins. An operator 46 carries a smartphone as the external device 6, and by pressing the "inertial sensor measurement" button on the external device 6, acquisition of angular velocity data from the gyro sensor 321 and acceleration data from the acceleration sensor 322 begins.

[0034] When measurement begins, the electric winch 42 begins operating and winds up the wire 4 at a constant speed. As the wire 4 is wound up at a constant speed, the measuring device 1 is pulled up from the pipeline 41 and moves through the pipeline 41 at a constant speed. While the measuring device 1 is moving, the operator 46 can press the "Display sensor information graph" button on the operation screen of the external device 6 to display a graph of real-time measurements taken by the gyro sensor 321 and the acceleration sensor 322 during measurement. The operator 46 can also press the "Measure distance and take a camera shot" button on the operation screen of the external device 6 to take images at predetermined intervals, measure the distance from the pipeline end 45 at the time of shooting, and add the measured images to the image data and store them. The operator 46 can also press the "Take a camera shot" button on the operation screen of the external device 6 to check the conditions inside the pipeline 41 during measurement in real time using the captured images.

[0035] In this way, the electric winch 42 pulls up the measuring device 1 at a constant speed, and when the measuring device 1 moves from the measurement start position to the measurement end position, which is the entrance of the pipeline 41, the operator 46 presses the "measurement end" button on the operation screen of the external device 6. This causes the measuring device 1 to end the measurement.

[0036] When the measurement is complete, the operator 46 presses the "Send Email" button on the operation screen of the external device 6, and the created measurement data files are sent by email to a pre-registered destination. The recipient of the email analyzes the received measurement data to calculate the path of the pipeline 41. In calculating the path, the depth of the pipeline 41 is analyzed from the angular velocity around the Y-axis. The planar position of the pipeline 41 is also analyzed from the angular velocity around the Z-axis. Note that the angular velocity around the X-axis is not used in the analysis. The inner casing 3 maintains a predetermined posture even in response to changes in the outer casing 2, so there is no change around the X-axis. Therefore, it does not need to be taken into account in calculating the path. The acquired angular velocity [rad / s] is multiplied by a predetermined measurement time interval [s] to calculate the angular change [rad] per measurement time interval. The position of the pipeline 41 in the X-axis direction is calculated from the cosine value of the integrated value of the angular change [rad] per measurement time interval calculated for the angular velocity around the Z-axis, and the position of the pipeline 41 in the X-axis direction is calculated from the sine value of the integrated value. Similarly, the depth of the position of the pipeline 41 can be found from the angular velocity around the Y axis.

[0037] Next, another example of the arrangement of components mounted inside the inner housing 3 will be shown. As shown in Fig. 5, the inertial sensor 32, single-board computer 33, and battery 34 are arranged parallel to the axis 31, but are all arranged below the axis 31, and are placed on the weight 35 in the order of battery 34, single-board computer 33, and inertial sensor 32. By placing these components on the weight 35, these components form part of the weight. Therefore, the weight and size of the weight 35 itself can be reduced, and more space can be secured for the components.

[0038] As described above, the housing of the measuring device 1 has a double structure consisting of the outer housing 2 and the inner housing 3, and the only contact surface between the outer housing 2 and the inner housing 3 is the shaft 31 and bearing 21 attached to the center, allowing the inner housing 3 to rotate relative to the outer housing 2. Furthermore, weight 35 is added to the bottom surface of the inner housing 3. As a result, even when the outer housing 2 rotates, the inner housing 3, which houses the inertial sensor 32, does not rotate. Therefore, even when the measuring device 1 moves, the orientation of the inertial sensor 32 is maintained in a predetermined direction, and there is no risk of the orientation of the inertial sensor 32 changing unnecessarily due to contact with the inner wall of the pipe 41 or due to steps, etc., preventing the measurement data from being unable to be acquired correctly, and preventing any impact on the analysis accuracy.

[0039] In the above embodiment, the inner casing 3 is rotatably supported relative to the outer casing 2 by providing the bearing 21 on the outer casing 2 and the shaft 31 on the inner casing 3, but the inner casing 3 may also be rotatably supported relative to the outer casing 2 by providing the bearing 21 on the inner casing 3 and the shaft 31 on the outer casing 2.

[0040] In the above embodiment, the external device 6 performs the process of creating a sensor information graph, the process of creating attitude angle data based on angular velocity data and acceleration data, and the process of creating a file by adding distance data to the pipe end 45 to the captured image data. However, these processes may be performed by the single-board computer 33 in the measuring device 1.

[0041] The above embodiments are merely examples, and the present invention is not limited to these. Various embodiments are possible within the scope of the invention as defined in the claims. The components described in the embodiments and variations can be freely combined. Furthermore, inventions equivalent to the inventions defined in the claims are also included in the present invention. In addition, even if the components of the inventions defined in the claims have the same names as the components described in the above embodiments, they are not limited to the components described in the above embodiments themselves, and can be modified and applied as appropriate. [Explanation of symbols]

[0042] 1. Measuring equipment 2 Outer housing 3 Inner housing 23 Adapter 31 axes 32 Inertial Sensor 35 weight 36 Ultrasonic Sensor 37 Camera

Claims

1. A measuring device that is inserted into a pipeline and measures the position of the pipeline, an inner housing that holds the inertial sensor therein; an outer housing that holds the inner housing therein; the inner housing is supported by the outer housing so as to be rotatable about an axis extending along the pipe line direction, and includes a biasing portion that applies a force to maintain an attitude in the rotation direction. Measuring device.

2. The biasing portion is provided so that the center of gravity of the inner housing is eccentric from the axis. The measuring device according to claim 1 .

3. the biasing portion is a weight attached to the inner housing, and maintains the orientation of the inner housing in the rotation direction by its own weight; The measuring device according to claim 2 .

4. the biasing unit is a component including the inertial sensor held inside the inner housing in addition to the weight; The measuring device according to claim 3 .

5. an adapter having an outer diameter corresponding to the diameter of the pipe and fitted onto the outer periphery of the outer housing; The measuring device according to claim 1 .

6. the inertial sensor is at least one of a gyro sensor and an acceleration sensor; The measuring device according to claim 1 .

7. The inner housing further includes at least one of a camera that photographs the inside of the pipeline and a distance measuring sensor that measures the distance to an end of the pipeline. The measuring device according to claim 1 .

Images