JP2020091213A - Surface contamination density measurement system - Google Patents

Abstract

To provide a surface contamination density measurement system capable of ensuring desired measurement accuracy regardless of the measurer by unmanning each operation of sampling and surface contamination density measurement while reducing the exposure risk of measurer by eliminating the need to enter the control area of the measurer.SOLUTION: A surface contamination density measurement system 100 includes: a self-propelled sampling unit 1 that moves autonomously within the controlled area on the basis of map information and sampling at a predetermined point; and a surface contamination density measuring device 30 that is installed out of the measurement area and measures the surface contamination density of the sample collected by the self-propelled sampling device.SELECTED DRAWING: Figure 8

Description

The present invention relates to a surface contamination density measuring system for measuring the surface contamination density of a radiation-related facility.

Radiation-related facilities such as nuclear power plants are required by law to regularly measure the pollution status in the controlled area. However, when this legal measurement is performed by a man, there is a risk that the measurer will be exposed when sampling is performed at a high dose work place. In addition, there are multiple work steps for sampling, surface contamination density measurement, input of measurement results and preparation of measurement records. The error was easy to occur.

Patent Literature 1 and Patent Literature 2 are known as labor-saving systems for solving these problems.

Patent Document 1 describes "Smear filter paper with the same probe as the floor contamination measurement by the direct method in which the probe for surface contamination measurement is lowered and brought close to the floor while self-propelled in the measurement area in the solution section of the abstract. In addition to performing two types of radiation measurement on the floor surface F, including the floor contamination measurement by the indirect method using the method, after the radiation measurement at the predetermined measurement points, the wheel contamination detection probe for the wheels as well as self-propelled to the survey area. Decontamination of radioactive substances by spraying decontamination water from a radiation survey and decontamination water nozzles, so radiation measurement can be performed across multiple measurement areas with different management levels without requiring human work. As described above, a traveling-type radiation monitor for measuring the contamination state of a floor surface on a traveling route by two methods, a direct method and an indirect method, is disclosed. This traveling radiation monitor moves while monitoring the situation with a camera, as described in paragraph 0018 of the same document.

Further, Japanese Patent Application Laid-Open No. 2004-242242 describes, in a solution section of an abstract, "The floor surface contamination measuring robot includes a main body portion, a moving means that is provided in the main body portion, and that moves the main body portion on the floor surface, and a lower surface side of the main body portion. And a radiation detecting means for detecting radiation on the floor surface. The main body part is formed in a circular shape in a top view. The radiation detecting means and the moving means are arranged from the outer peripheral surface of the main body part in a top view. It is mounted inside and is provided so as not to protrude from the outer peripheral surface of the main body portion.", a floor surface contamination measuring robot for measuring the floor surface contamination state by a direct method is disclosed. By arranging the respective parts as described above, this floor contamination measuring robot prevents the robot from becoming immovable due to collision with an obstacle, as described in paragraph 0020 of the same document.

JP, 2005-24345, A JP, 2016-148585, A

When measuring the surface contamination density in a radiation-related facility, a measurer with specialized knowledge selects a measurement location and conducts a contamination inspection. In many cases, the indirect method using smear filter paper is used to check the contamination of the floor of the facility. When performing a contamination inspection by the direct method, it is a prerequisite that a background value that does not affect the measurement can be obtained at the measurement site, and if the background value cannot be secured, a shield is required. In addition, there is a risk of exposure when entering a work place with a high dose in human measurements, which may lead to body contamination in the measurement of surface contamination density.

To solve this problem, Patent Document 1 makes it possible to unmanned the surface contamination density measurement by using a self-propelled radiation monitor that stores a traveling route. However, with this method, it is necessary to store the travel route in advance, and if there is a difference between the situation of the work place and the stored travel route, manned remote control using a camera is also required, which saves labor. The effect diminishes. Further, although it has a decontamination mechanism when the tire portion of the main body is contaminated, it is necessary to move to a dedicated place because it is decontamination by watering, and there is a possibility that the pollution is propagated during the movement.

Further, in the floor surface contamination measuring system of Patent Document 2, as in Patent Document 1, the moving route is stored in advance and the surface contamination density is measured by self-propelled. The measurement method is a direct method, and it is possible to create a distribution map by evaluating the degree of contamination with a threshold value. However, since no shield is installed, the detection limit value becomes large due to the influence of the background in a work environment with a radiation dose, and therefore the presence or absence of contamination cannot be determined. In the direct method, taking a GM tube type survey meter as an example, it is recommended that the moving speed of the detection part be about several cm/sec, and it takes time when trying to measure the entire large floor. Will end up.

As described above, in both Patent Documents 1 and 2, the main body is provided with a means for measuring the surface contamination density, but no shield is provided, and the measuring means is used in a work place with a radiation dose. The use of is restricted. Further, in both Patent Document 1 and Patent Document 2, self-propelling is possible by storing the moving route in advance, but when the situation of the work place and the stored traveling route differ, the moving route There is no mechanism that corrects, and it may not be possible to measure at the correct measurement point.

Therefore, in the present invention, each work of sampling and surface contamination density measurement is performed by a self-propelled sampler that autonomously travels in a high-dose control area, and a surface contamination-density measurement apparatus installed outside a low-dose measurement area. By not dividing the exposure risk of the measurer by eliminating the need for the measurer to enter the controlled area, by unmanning each work of sampling and surface contamination density measurement, It is an object of the present invention to provide a surface contamination density measuring system capable of realizing highly accurate surface contamination density measurement regardless of the person who measures it.

In order to achieve the above object, the surface contamination density measurement system of the present invention is a self-propelled sampling device that autonomously moves within a controlled area based on map information and samples at a predetermined location, and outside the measurement area. A surface contamination density measuring device that is installed and measures the surface contamination density of the sample collected by the self-propelled sampler.

ADVANTAGE OF THE INVENTION According to this invention, a measurer can sample a sample at an accurate measurement point without entering a controlled area, and it is possible to automate the preparation of a measurement record. This leads to reduction of exposure, prevention of body pollution, and improvement of work efficiency.

The schematic perspective view of the self-propelled sampler concerning one Example. The bottom view of the self-propelled sampler of FIG. FIG. 2 is a side view of a sampling portion of the self-propelled sampling device in FIG. 1. FIG. 2 is a top view of a sampling portion of the self-propelled sampling device in FIG. 1. The side view of the self-propelled sampler of FIG. 1 is a schematic perspective view of a surface contamination density measuring device according to an embodiment. The top view of the surface contamination density measuring apparatus of FIG. 1 is a schematic perspective view of a surface contamination density measuring system according to an embodiment.

A surface contamination density measuring system 100 according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 8 is a schematic perspective view of a surface contamination density measuring system 100 of the present embodiment, which measures the surface contamination density of radiation related facilities such as a nuclear power plant. This surface contamination density measuring system 100 is a system in which each work of sampling and measuring surface contamination density is shared by a sampling device and a sample analysis device. Specifically, it autonomously runs in a high-dose controlled area. However, the self-propelled sampling device 1 that samples at a designated place, and the surface contamination density that measures the surface contamination density of the collected sample outside the low-dose measurement area where a background value that does not affect the measurement can be obtained It is a system including a measuring device 30. In the following, the self-propelled sampling device 1 and the surface contamination density measuring device 30 will be described individually, and then the operation method of the surface contamination density measuring system 100 that combines the two will be described.
<Self-propelled sampling device 1>
FIG. 1 is a schematic perspective view of a self-propelled sampling device 1 that constitutes a surface contamination density measuring system 100 of this embodiment. This self-propelled sampling device 1 is provided with a main body 2 formed in a circular shape in a top view like many commercially available robot cleaners, and various devices to be described later are provided therein.

An environmental sensor 3 (infrared sensor 3a, ultrasonic sensor 3b, camera sensor 3c) is provided on the outer peripheral surface of the main body 2 for observing the external environment and preventing a collision with a wall or an obstacle. In addition, in FIG. 1, as the environment sensor, a configuration in which a pair of infrared sensor 3a, ultrasonic sensor 3b, and camera sensor 3c are provided on the front surface of the main body 2 is illustrated. A gyro sensor, a distance sensor, or the like may be used in combination as the environment sensor 3.

On the upper surface of the main body 2, there is provided an operation panel 4 having buttons and a liquid crystal screen for the operator to operate. Further, a control device 5 is provided inside the main body 2. The control device 5 is a computer including a storage device such as a semiconductor memory and an arithmetic device such as a CPU that realizes a desired function by executing a program read in the storage device. Then, the control device 5 controls the drive mechanism 6b, which will be described later, and sequentially superimposes the data obtained from each sensor, and determines the self-position and the movement amount of the main body 2 from the movement amount of the scan data at the time of the superposition. The mapping AI, which is sequentially estimated, is realized.

FIG. 2 is a bottom view of the self-propelled sampling device 1. As shown here, the self-propelled sampling device 1 includes wheels 6 a provided on both left and right sides of the bottom surface of the main body 2 and a moving device 6 including a drive mechanism 6 b provided inside the main body 2. .. The drive mechanism 6b is a combination of a motor, a speed change device and the like, and the control device 5 changes the rotational speed of the left and right wheels 6a via the drive mechanism 6b to enable autonomous movement in the front, rear, left and right directions.

Further, the bottom surface of the main body 2 is provided with an auxiliary wheel that also functions as a traveling sensor 3d that detects inability to travel while traveling, and a connecting portion 7 for electrically connecting to the surface contamination density measuring device 30. There is. Then, the control device 5 can communicate with the surface contamination density measuring device 30 via the connection portion 7, and the rechargeable battery (not shown) inside the main body 2 is charged by the power supply from the surface contamination density measuring device 30. Is possible.

Further, inside the main body 2, a sampling section 10 for measuring the surface contamination density of the radiation-related facility by the indirect method is provided. The sample collecting unit 10 has a mechanism in which a filter paper crimping tool 12 to which a smear filter paper 11 is attached is projected from the bottom of the main body 2 and the smear filter paper 11 is crimped to the floor surface of the work place.

FIG. 3 is a side view of the sample collecting unit 10 of the self-propelled sample collecting apparatus 1. As shown here, the sample collecting unit 10 is divided into three regions: a pre-collection filter paper storage unit 10a, a filter paper pressure bonding unit 10b, and a post-collection filter paper storage unit 10c. The pre-collection filter paper storage unit 10a is an area in which a plurality of unused smear filter papers 11a mounted in a dedicated holder can be stored. The filter paper crimping portion 10b is an area provided with the filter paper crimping tool 12 and the crimping motor 12a. The rotational force of the crimping motor 12a is converted into the vertical movement of the filter paper crimping tool 12, and the filter paper crimping tool 12 is projected to smear. The filter paper 11b is pressure-bonded to the floor surface, and a sample at that location is collected. The post-collection filter paper storage unit 10c is an area capable of storing a plurality of sampled smear filter papers 11c.

FIG. 4 is a top view of the sample collecting unit 10 of the self-propelled sample collecting device 1, in which the smear filter paper 11 mounted on the dedicated holder is transferred from the pre-collection filter paper storing unit 10a to the filter paper crimping unit 10b and further to the filter paper crimping unit. It shows a state of sequentially transferring from 10b to the filter paper storage unit 10c after collection. The smear filter paper 11 is transferred by rotating the rotating mechanism 13 provided in the lower portion of the sample collecting unit 10 in a desired direction with the filter paper crimping tool 12 being pulled up. More specifically, the transfer from the pre-collection filter paper storage unit 10a to the filter paper pressure bonding unit 10b is performed by rotating the rotating mechanism 13a having a rotation axis at the boundary between both regions in the clockwise direction, and the transfer from the filter paper pressure bonding unit 10b is performed. The transfer to the filter paper storage unit 10c after collection is performed by rotating the rotation mechanism 13b having a rotation axis at the boundary between both regions counterclockwise.

As shown in FIG. 3, since many unused smear filter papers 11a are stored in the pre-collection filter paper storage unit 10a, the smear filter papers 11b of the filter paper crimping unit 10b are stored in the post-collection filter paper storage unit 10c. After that, the unused smear filter paper 11a can be replenished from the pre-collection filter paper storage unit 10a to the filter paper pressure bonding unit 10b.

FIG. 5 is a side view of the self-propelled sampling device 1, and illustrates a configuration for decontaminating the wheel 6a and the auxiliary wheel (travel sensor 3d). As shown here, the wheels 6a and the auxiliary wheels are provided so as to be exposed from the bottom surface of the main body 2, and as a result, there is a space of several tens of mm between the floor surface and the bottom surface of the main body 2. Inside the main body 2, there is provided a decontamination device 8 for removing the contaminants adhering to the wheels 6a and the auxiliary wheels. The decontamination device 8 is pressed against the wheels 6a and the auxiliary wheels to wipe off the surfaces of them. can do. The decontamination by the decontamination device 8 is performed, for example, by a dry method using a take-up type chemical rag (a cloth having a decontamination effect by static electricity such as rayon nonwoven fabric). After the sample is collected, the wheel 6a is pressed for a certain period of time, and the wheel 6a and the auxiliary wheel are decontaminated while moving. After decontamination, the used parts such as chemical rags are rolled up.

In Patent Document 1, since decontamination water is used to decontaminate the wheels, the decontamination place is limited, but in the self-propelled sampling apparatus 1 of the present embodiment, the decontamination device described above is used. By using 8, the wheel can be decontaminated at any place.
<Surface contamination density measuring device 30>
FIG. 6 is a schematic perspective view of the surface contamination density measuring device 30 that constitutes the surface contamination density measuring system 100 of the present embodiment. This surface contamination density measuring device 30 is installed in a state connected to a commercial power source outside a low-dose controlled area where the risk of exposure to the measurer is low, and mainly consists of a central body 31 and left and right analysis thereof. It is composed of a front sample dish storage section 32a and a post-analysis sample dish storage section 32c.

On the front surface of the main body 31, there are provided an operation panel 39 composed of buttons operated by a measurer and a liquid crystal screen, and a connecting portion 34 for electrically connecting to the connecting portion 7 of the self-propelled sampling device 1. .. Further, on the front surface of the main body 31, there is provided a slope 38 that serves as a path when the self-propelled sampling device 1 approaches the connection portion 34, and a slope between the connection portion 34 and the slope 38 is opened and closed. A sample carry-in section 37 having a formal opening mechanism is provided. Then, the smear filter paper 11c that has been sampled is carried into the surface contamination density measuring device 30 connected to the self-propelled sample collecting device 1 via the sample carrying-in part 37, and mapping AI is carried out via the connecting part 34. The estimated collection place by is input.

Further, inside the main body 31, an analysis device 35 and a record creation unit 36 for recording the analysis result of the analysis device 35 are provided. The analysis device 35 is a device that measures the surface contamination density from the smear filter paper 11c that has been carried in, and is used in combination with, for example, a gas flow counter, a plastic scintillator, a ZnS scintillator, or the like. On the other hand, the record creating unit 36 records the analysis result of the analyzer 35 together with the estimated collection place of the collected sample. The main body 31 of the pollution density measuring device 30 can be connected to an external PC or a tablet terminal by wire or wirelessly, and can communicate information with each other.

FIG. 7 is a top view of the contamination density measuring device 30. As shown here, inside the main body 31 of the surface contamination density measuring device 30, a transfer unit 32b that rotates in both forward and reverse directions is provided. The transfer section 32b has a plurality of dents for transferring the sample dish to the outer periphery thereof, and the smear filter paper 11c loaded from the self-propelled sample collecting device 1 via the sample loading section 37 is placed on the sample dish. It can be transferred to a desired position.
<Surface contamination density measuring system 100>
A specific operation method of the surface contamination density measuring system 100 of this embodiment, which includes the self-propelled sampling device 1 and the surface contamination density measuring device 30 described above, will be sequentially described in detail below.
<Autonomous movement of the self-propelled sampling device 1 to the measurement point>
First, as shown in FIG. 8, in a state where the connecting portions of the self-propelled sampling device 1 and the surface contamination density measuring device 30 are connected to each other, an external PC or the like is used to measure the surface contamination density by the surface contamination density measuring device 30. Enter the necessary information (map information of radiation related facilities and sample collection point information). As a result, the self-propelled sampling device 1 can recognize the measurement range and the sampling place via the surface contamination density measuring device 30.

When recognizing the measurement range and the sampling place, the control device 5 of the self-propelled sampling device 1 controls the moving device 6 to start the autonomous movement to the sampling place. At the time of autonomous movement, information obtained from the infrared sensor 3a, the ultrasonic sensor 3b, the camera sensor 3c, and the traveling sensor 3d is integrated by the control device 5, and obstacle avoidance and self-position estimation by the mapping AI are processed in parallel. As a result, even when the surrounding environment changes, it is possible to move to the destination while avoiding obstacles and the like. In addition, the control device 5 stores the moving path in which the estimated self-position of the self-propelled sampling device 1 is continuously recorded, and decontamination is necessary even if the contamination is propagated by the wheel 6a or the like. You can narrow down the range.
<Sampling by the self-propelled sampling device 1>
When the self-propelled sample collecting device 1 arrives at the sample collecting place, the filter paper crimping tool 12 is projected from the sample collecting section 10 toward the floor surface as shown by the broken line in FIG. Then, the smear filter paper 11b is crimped to the floor surface by the filter paper crimping tool 12, and the self-propelled sampling device 1 is moved concentrically to collect a sample at this sampling place. When the sampling in a certain range is completed (for example, after the movement of about 100 cm ² is completed), the filter paper crimping tool 12 is stored in the main body. Then, in the sample collecting section 10, as shown in FIG. 4, the smear filter paper 11b used for sample collection is transferred to the filter paper storage section 10c after collection and the unused smear filter paper 11b transferred from the pre-collection filter paper storage section 10a. The smear filter paper 11a is attached to the filter paper crimping tool 12. When the replacement work of the smear filter paper 11 is completed, the self-propelled sample collection device 1 autonomously moves to the next sample collection place and executes the above sample collection work again.
<Surface contamination density measurement by surface contamination density measuring device 30>
When the sampling at all places designated by the measurer or the like is completed, the self-propelled sampling device 1 climbs the slope 38 of the surface contamination density measuring device 30 installed outside the controlled area, and connects itself. 7 is connected to the connecting portion 34 of the surface contamination density measuring device 30 by itself. When the connecting parts are connected to each other, the sample carrying-in part 37 of the surface contamination density measuring device 30 is opened, and the smeared filter paper 11c which has been sampled is transferred from the self-propelled sample collecting device 1 to the inside of the main body 31.

As shown in FIG. 7, since the transfer section 32b inside the surface contamination density measuring device 30 has a mechanism that rotates in both left and right directions, an empty sample dish and the smear filter paper 11c before and after the analysis are placed by this. The sample pan is transferred. Specifically, first, the empty sample dish supplied from the pre-analysis sample dish storing section 32a on the left side of FIG. 7 is transferred to the lower side of the sample loading section 37 on the lower side of FIG. 7 by the transfer section 32b. .. Then, the sample dish on which the smear filter paper 11c is placed is transferred to the vicinity of the analyzer 35 on the upper side of FIG. 7 by the transfer section 32b. When the analysis of the smear filter paper 11c by the analyzer 35 is completed, the sample dish on which the smear filter paper 11c is placed is transferred to the post-analysis sample plate storage part 32c by the transfer part 32b. This series of operations is executed for all the samples (smear filter paper 11c) in the self-propelled sampling device 1.
<Measurement record creation>
When the connection part of the self-propelled sample collecting device 1 and the surface contamination density measuring device 30 is connected, the controller 5 of the self-propelled sample collecting device 1 to the record creating part 36 of the surface contamination density measuring device 30 sends an external PC. The error between the map information input from the etc. and the actual environment detected by the mapping AI and the information of the sampling point are transmitted.

Further, when the measurement of the surface contamination density by the analyzer 35 is completed, the measurement result is stored in the recording creating unit 36. Then, the record creating unit 36 creates a measurement record in which the error of the actual environment and the measurement result of each place in the management area are reflected on the map of the management area input in advance. The measurement record created here is output to an external PC or the like connected to the surface contamination density measuring device 30, and the measurer confirms the surface contamination density or the like at various places in the controlled area via a monitor or the like of the external PC. It becomes possible.

As described above, according to the surface contamination density measurement system of the present embodiment, each work of sampling and surface contamination density measurement, a self-propelled sampling device that autonomously travels in a high-dose controlled area, The surface contamination density measurement device installed outside the low-dose measurement area is shared with the measurement device, eliminating the need for the operator to enter the controlled area, which not only suppresses the exposure risk of the operator but also contributes to sampling. By unmanning each work of surface contamination density measurement, highly accurate surface contamination density measurement can be realized regardless of the person who measures the surface.

100: Surface contamination density measuring system 1: Self-propelled sampling device 2: Main body 3: Environmental sensor 3a: Infrared sensor 3b: Ultrasonic sensor 3c: Camera sensor 3d: Running sensor 4: Operation panel 5: Control device 6: Move Device 6a: Wheel 6b: Drive mechanism 7: Connection part 8: Decontamination device 10: Sampling part 10a: Filter paper storage part before sampling 10b: Filter paper crimping part 10c: Filter paper storage part 11, 11a, 11b, 11c after sampling: Smear Filter paper 12: Filter paper crimping tool 12a: Pressing motors 13, 13a, 13b: Rotation mechanism 30: Surface contamination density measuring device 31: Main body 32a: Pre-analysis sample dish storage section 32b: Transfer section 32c: Post-analysis sample dish storage section 34 : Connection part 35: Analytical device 36: Record creation part 37: Sample loading part 38: Slope 39: Operation panel

Claims (10)

A self-propelled sampling device that autonomously moves within the controlled area based on map information and samples at a predetermined location,
A surface contamination density measuring device that is installed outside the measurement area and that measures the surface contamination density of the sample collected by the self-propelled sampling device,
A surface contamination density measuring system comprising: The surface contamination density measuring system according to claim 1,
The self-propelled sampling device,
An environmental sensor that observes the external environment,
A controller for estimating a self-position based on the output of the environment sensor,
A surface contamination density measuring system comprising: The surface contamination density measuring system according to claim 2,
The controller is a mapping AI that sequentially superimposes data obtained from the environment sensor and sequentially estimates the self-position and the movement amount from the movement amount of scan data at the time of superposition. Density measurement system. The surface contamination density measuring system according to claim 2 or 3,
The control device is
A surface contamination density measuring system characterized by storing a moving path in which the estimated self-position is continuously recorded. The surface contamination density measuring system according to claim 1,
The self-propelled sampling device,
A surface contamination density measuring system characterized by autonomously moving to the surface contamination density measuring apparatus after the sample collection is completed, and transferring the collected sample to the surface contamination density measuring apparatus. The surface contamination density measuring system according to claim 1,
The self-propelled sampling device,
It is equipped with a sample collection unit consisting of a filter paper storage unit before collection, a filter paper pressure bonding unit, and a filter paper storage unit after collection,
The smear filter paper stored in the pre-collection filter paper storage unit is transferred to the filter paper crimping unit, used for sampling, and then stored in the post-collection filter paper storage unit. .. The surface contamination density measuring system according to claim 1,
The self-propelled sampling device,
A moving device including wheels and a drive mechanism,
A decontamination device for wiping the surface of the wheel,
A surface contamination density measuring system comprising: The surface contamination density measuring system according to claim 1,
The surface contamination density measuring device,
After the measurement of the surface contamination density of the sampled sample was completed, the collection location of the sampled sample transmitted from the self-propelled sampler and the measurement result of the sampled sample were reflected on the map of the controlled area. A surface contamination density measuring system, characterized in that a measurement record is created. The surface contamination density measuring system according to claim 8,
The surface contamination density measuring device,
A surface contamination density measuring system characterized by creating a measurement record in which an error between the map information and an actual environment observed by the self-propelled sampling device is reflected on a map of the controlled area. The surface contamination density measuring system according to claim 1,
The surface contamination density measuring device,
A sample carry-in section into which a sample collected from the self-propelled sample collecting device is carried in;
A pre-analysis sample dish storage unit in which an empty sample dish is stored;
An analyzer for analyzing the surface contamination density of the collected sample placed on the sample dish,
A post-analysis sample dish storage unit for storing a sample dish after analysis,
A transfer unit for transferring the sample dish between them,
A surface contamination density measuring system comprising:

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