JP2026073643A - Inspection equipment - Google Patents

Abstract

[Problem] To provide an inspection device capable of determining whether or not a perovskite-type solar panel is malfunctioning.
[Solution] The inspection device is an inspection device for a perovskite type solar panel, and comprises a wheel, a movement control unit that controls the movement of the wheel, an illumination unit that illuminates the solar panel, an imaging unit that generates at least one inspection image by photographing the area of the solar panel illuminated by the illumination unit, and a determination unit that determines whether or not the solar panel is faulty based on the inspection image.
[Selection Diagram] Figure 3

Description

This disclosure relates to a technology for inspecting solar panels.

Patent Document 1 discloses a cleaning device for detecting high-temperature areas of a solar power generation panel as fault locations. Specifically, the cleaning device of Patent Document 1 comprises a movable frame, a cleaning body, a detection means, and a damage detection means. The movable frame is movable in the horizontal direction. The movable frame consists of a pair of clamping members that clamp the solar power generation panel from above and below, and a guide rail that spans the pair of clamping members. The cleaning body is mounted on the guide rail so as to be vertically movable. The detection means is installed on the cleaning body and detects the surface condition of the solar panel. The detection means consists of a thermographic camera, a position information acquisition means, and an inspection image data transmission means. The thermographic camera takes surface images of the solar power generation panel at regular intervals. The position information acquisition means acquires the position information of the solar power generation panel captured by the thermographic camera and associates it with the surface images of the solar power generation panel. The inspection image data transmission means sequentially transmits the inspection image data to the damage detection means. The damage detection system automatically extracts inspection image data containing high-temperature areas from the received inspection image data and identifies damaged or defective areas of the solar power generation panel based on the location information.

International Publication No. 2016-024304

The technology described in Patent Document 1 identifies damaged or defective areas based on the heat generated by the solar panel. However, when using perovskite-type solar panels, it is difficult to determine whether or not the solar panel is malfunctioning based solely on the heat generated.

This disclosure was made to address these issues and aims to provide an inspection device capable of determining whether or not a perovskite-type solar panel is malfunctioning.

An inspection apparatus in one aspect of this disclosure is an inspection apparatus for a perovskite-type solar panel, comprising: a wheel; a movement control unit for controlling the movement of the wheel; an illumination unit for illuminating the solar panel; an imaging unit for generating at least one inspection image by capturing a region of the solar panel illuminated by the illumination unit; and a determination unit for determining whether or not the solar panel is faulty based on the inspection image.

According to this disclosure, it is possible to determine whether or not a perovskite-type solar panel is malfunctioning.

This figure shows the external appearance of the inspection device in Embodiment 1. This is a cross-sectional view of the inspection apparatus shown in Figure 1, taken along line II-II. This block diagram shows the electrical configuration of the inspection device. This is a magnified view of a portion of a solar panel showing an area where mild yellowing has occurred. This is a magnified view of a section showing an area of severe yellowing occurring on a solar panel. This is a block diagram showing the configuration of the inspection device according to Embodiment 2. This is a cross-sectional view of the inspection device according to Embodiment 2. This is a block diagram showing the configuration of the inspection device according to Embodiment 3.

(The circumstances leading to one aspect of this disclosure)
In recent years, renewable energy has attracted attention from the perspective of environmental protection and preventing global warming. In particular, flexible perovskite-type solar panels, which can be made thinner and lighter, are attracting attention.

To efficiently operate perovskite-type solar panels, it is crucial to accurately inspect whether or not the panels are degrading. Furthermore, if degradation is significantly advanced, it is important to determine that the solar panels are faulty and replace them as necessary.

The inventors, through extensive research on perovskite-type solar panels, have found that the degradation of perovskite-type solar panels does not necessarily manifest as temperature changes, but can also manifest as changes in appearance. In other words, they have found that detecting the degradation of perovskite-type solar panels is difficult using methods such as the one disclosed in Patent Document 1, which involves using a thermographic camera to identify damaged or defective areas.

This disclosure is based on such findings.

(1) An inspection apparatus in one aspect of the present disclosure is an inspection apparatus for a perovskite-type solar panel, comprising: a wheel; a movement control unit for controlling the movement of the wheel; an illumination unit for illuminating the solar panel; an imaging unit for generating at least one inspection image by capturing an area of the solar panel illuminated by the illumination unit; and a determination unit for determining whether or not the solar panel is faulty based on the inspection image.

According to this configuration, whether or not a perovskite-type solar panel (hereinafter referred to as "solar panel") is faulty is determined based on inspection images generated by photographing the solar panel. In other words, the inspection device determines whether or not a solar panel is faulty based on its appearance. This allows for the determination of whether or not a perovskite-type solar panel is faulty.

(2) In the inspection apparatus described in (1) above, the imaging unit may further include an image synthesis unit that generates a plurality of inspection images and synthesizes the plurality of inspection images based on the movement amount of the inspection apparatus to generate a composite image, and the determination unit may determine whether or not the solar panel is malfunctioning based on the composite image.

In this configuration, the image synthesis unit generates a composite image by combining multiple inspection images using the movement of the inspection device. The determination unit determines whether or not the solar panel is faulty based on this composite image. In this way, even when the entire solar panel or a predetermined area of the solar panel does not fit within a single inspection image, the inspection device can determine whether or not the solar panel is faulty based on the composite image. Therefore, the inspection device can more reliably determine whether or not the solar panel is faulty.

(3) In the inspection apparatus described in (2) above, the image synthesis unit may extract a first feature point from the first inspection image among the plurality of inspection images, extract a second feature point corresponding to the first feature point from the second inspection image taken after the first inspection image, and estimate the amount of movement of the inspection apparatus based on the first feature point and the second feature point.

This configuration allows for a more accurate estimation of the inspection device's movement by utilizing feature points contained in the image. Furthermore, by generating a composite image based on the more accurately estimated movement, it becomes possible to produce a high-precision composite image.

(4) In the inspection apparatus described in (2) or (3) above, a wheel sensor for measuring the rotation speed of the wheel may be further provided, and the image synthesis unit may estimate the amount of movement of the inspection apparatus based on the rotation speed measured by the wheel sensor.

This configuration allows for a more accurate estimation of the inspection device's movement by utilizing the wheel rotation speed. Furthermore, by generating a composite image based on the more accurately estimated movement, it becomes possible to produce a high-precision composite image.

(5) In the inspection apparatus described in any one of (1) to (4) above, the illumination unit irradiates the solar panel with white light, the imaging unit generates a white inspection image which is the inspection image generated by imaging the solar panel irradiated with the white light, and the determination unit detects yellowed regions from the white inspection image where the pixel values satisfy the yellowed region conditions, and determines whether or not the solar panel is faulty based on the area of the yellowed regions.

When perovskite-type solar panels degrade, lead and iodine in the perovskite crystal structure combine, sometimes forming yellowed areas (mainly lead iodide). This phenomenon is referred to as "yellowing" in this specification.

According to the above configuration, whether or not a solar panel is faulty is determined based on the area of yellowing in the white inspection image. This allows for the detection of yellowing in the solar panel.

Furthermore, in the above configuration, the inspection device determines whether or not the solar panel is faulty based on the area of the yellowed region captured in the white inspection image. Therefore, the inspection device can determine, for example, that the solar panel is faulty when the yellowing has expanded to a certain extent.

(6) In the inspection apparatus described in any one of (2) to (5) above, the illumination unit irradiates the solar panel with white light, the imaging unit generates multiple white inspection images by imaging the solar panel irradiated with the white light, the image synthesis unit generates a white composite image by synthesizing the multiple white inspection images, and the determination unit detects yellowed regions from the white composite image where the pixel values satisfy the yellowed region conditions, and determines whether the solar panel is faulty based on the area of the yellowed regions.

According to this configuration, whether or not a solar panel is faulty is determined based on the area of yellowed regions in a white composite image generated from multiple white inspection images. This allows for determination of whether or not a solar panel is faulty, even when yellowing is present in various parts of the solar panel and it is difficult to capture all of these yellowed areas in a single white inspection image, by utilizing the white composite image.

(7) In the inspection apparatus described in any one of (2) to (6) above, the illumination unit irradiates the solar panel with white light and yellow light; the imaging unit photographs the solar panel irradiated with the white light to generate a plurality of white inspection images; photographs the solar panel irradiated with the yellow light to generate a plurality of yellow inspection images; the image synthesis unit generates a white composite image based on the plurality of white inspection images; and generates a yellow composite image based on the plurality of yellow inspection images; and the determination unit generates a difference image between the white composite image and the yellow composite image, and determines whether or not the solar panel is faulty based on the difference image.

This configuration generates a difference image based on a white-based composite image and a yellow-based composite image. In other words, an image is generated that highlights any abnormalities in the appearance of the solar panel. By using this difference image to determine whether or not the solar panel is faulty, the accuracy of the determination can be improved.

(8) In the inspection apparatus described in any one of (2) to (7) above, the determination unit may determine whether or not the solar panel is malfunctioning based on the change in the color intensity of a specific region in the composite image.

Perovskite-type solar panels may experience color changes in specific areas as they degrade. For example, the color of certain areas may become lighter.

According to the above configuration, the determination unit determines whether or not the solar panel is malfunctioning based on the color change of a specific area in the composite image, thereby enabling a more reliable determination of whether or not the solar panel is malfunctioning.

(9) In the inspection apparatus described in any one of (1) to (8) above, the imaging unit may capture the inspection image at the same imaging location at different times, and the determination unit may detect a change in the color intensity of a specific area in the inspection image each time the imaging unit captures an image, and determine whether or not the solar panel is malfunctioning based on the change in the color intensity of the specific area.

In this configuration, the inspection device captures inspection images at the same location but at different times. In other words, the inspection device periodically takes images at specific points on the solar panel. Through these periodic captures, the inspection device detects changes in the color intensity of specific areas of the solar panel and determines whether or not the solar panel is faulty. This allows for a more reliable determination of whether or not the solar panel is faulty.

(10) The inspection apparatus described in any one of (1) to (9) above may further include a main body and an adsorption mechanism disposed at the bottom of the main body for adsorbing the main body onto the solar panel.

This configuration allows the inspection device to be attached to the solar panel. This prevents the inspection device from falling off the solar panel due to its own weight when the perovskite solar panel is installed along a vertical surface such as a wall or window.

(11) The inspection device described in any one of (1) to (10) above may further include a main body and a cleaning unit disposed at the bottom of the main body for cleaning the surface of the solar panel.

This configuration allows the inspection device to move across the solar panels to check for malfunctions while simultaneously cleaning the panels' surfaces. This approach is more efficient than performing malfunction detection and surface cleaning separately.

(12) The inspection apparatus described in any one of (1) to (11) above may further include a repair mechanism comprising: a repair agent storage unit for storing a repair agent; and a repair agent application unit for applying the repair agent supplied from the repair agent storage unit to the surface of the solar panel.

This configuration allows the inspection device to move across the solar panels to check for malfunctions while simultaneously repairing them. This is more efficient than performing fault inspection and solar panel repair separately.

The embodiments of this disclosure will be described below with reference to the drawings. Note that the embodiments described below are all specific examples of this disclosure. The numerical values, shapes, components, steps, and order of steps shown in the following embodiments are examples only and are not intended to limit this disclosure. Furthermore, components in the following embodiments that are not described in the independent claim representing the highest-level concept will be described as optional components. Also, the contents of each embodiment can be combined.

(Embodiment 1)
Figure 1 shows the external appearance of the inspection device 100 in Embodiment 1 of the present disclosure. More specifically, Figure 1 shows the external appearance of the inspection device 100 when viewed from below. Figure 2 is a cross-sectional view of the inspection device 100 shown in Figure 1, taken along line II-II. Figure 3 is a block diagram showing the electrical configuration of the inspection device 100.

The inspection device 100 moves along the perovskite-type solar panel 50 (hereinafter simply referred to as the solar panel 50) and takes pictures of the solar panel 50 to generate inspection images. Based on these inspection images, it determines whether or not the solar panel 50 is malfunctioning.

The solar panel 50 according to this embodiment is installed on the surface of a window. The window is supported by a building's window frame or the like, and stands upright in the vertical direction (up and down direction). The window surface has a rectangular shape, with its longitudinal direction extending vertically and its transverse longitudinal direction extending horizontally. The solar panel 50, having a shape corresponding to this window surface, is attached to the window surface. That is, in this embodiment, a rectangular solar panel 50 is attached to the window surface. However, this is merely an example, and the solar panel 50 may also be attached to the surface of a horizontal base, an inclined base, etc.

As shown in Figures 1 to 3, the inspection device 100 mainly comprises a main body 1, wheels 2, a drive unit 3 (Figure 3), a wheel sensor 4 (Figure 3), a posture sensor 5 (Figure 3), a suction mechanism 6 (Figure 3), a lighting device 7, an imaging device 8, a processor 10 (Figure 3), and a memory 20 (Figure 3).

The main body 1 is a box-shaped housing. As shown in Figures 1 and 2, the main body 1 has a recess D formed by a portion of the lower surface 1a of the main body 1 being recessed upward.

The wheels 2 rotate by receiving torque from the drive unit 3, thereby moving the inspection device 100. The wheels 2 are mounted on the lower surface 1a of the main body 1, with a portion of the wheel 2 exposed. The inspection device 100 is equipped with two wheels 2. In this embodiment, the wheels 2 are made of circular tires. However, the wheels 2 may also be made of continuous tracks such as crawlers.

Referring to Figure 3, the drive unit 3 rotates the wheels 2 based on control signals received from the movement control unit 11, which will be described later. The drive unit 3 includes two motors corresponding to the two wheels 2. As the drive unit 3 rotates the wheels 2, the inspection device 100 moves across the solar panel 50.

The wheel sensor 4 measures the rotation speed of the wheel 2. The rotation speed of the wheel 2 is used to estimate the amount of movement of the inspection device 100.

The attitude sensor 5 measures the attitude of the inspection device 100. The attitude sensor 5 is composed of, for example, a gyroscope or an accelerometer. The attitude of the inspection device 100 is used to estimate the direction of movement of the inspection device 100.

Although not shown in the diagram, the inspection device 100 may further include various sensors, such as an infrared sensor for recognizing objects around the inspection device 100 and a GPS sensor for measuring the current location of the inspection device 100.

The suction mechanism 6 attaches the main body 1 to the surface of the solar panel 50. The suction mechanism 6 includes, for example, a suction cup 6a (Figure 1) positioned at the bottom of the main body 1, and a suction pump (not shown) housed within the main body 1 and connected to the suction cup 6a. The suction mechanism 6 utilizes the suction force generated by this suction pump to attach the main body 1 to the surface of the solar panel 50. The suction pump generates a suction force that prevents the inspection device 100 from detaching from the surface of the solar panel 50 while allowing the inspection device 100 to move across the surface of the solar panel 50.

The lighting device 7 illuminates the solar panel 50 by emitting light according to a control signal received from the lighting control unit 12, which will be described later. The lighting device 7 is composed of a light-emitting element capable of changing the color of the emitted light to various colors such as white, yellow, and purple. For example, the lighting device 7 is composed of a full-color LED. As shown in Figures 1 and 2, the lighting device 7 is mounted on the upper (bottom) surface of the recess D. The inspection device 100 includes two lighting devices 7. Figure 2 illustrates the light L emitted from the lighting device 7. However, this is merely shown to facilitate understanding of this disclosure and is not intended to limit the illumination range of the lighting device 7. The lighting device 7 is an example of a lighting unit.

The imaging device 8 is a camera that generates at least one inspection image by capturing the area illuminated by the illumination device 7 on the solar panel 50. The imaging device 8 is configured, for example, as an RGB camera. That is, the imaging device 8 is configured as a camera capable of capturing color images. As shown in Figures 1 and 2, the imaging device 8 is mounted on the upper (bottom) surface of the recess D and positioned between the two illumination devices 7. The imaging device 8 is an example of an imaging unit.

Referring again to Figure 3, the processor 10 is composed of, for example, a central processing unit (CPU) located inside the main unit 1. The processor 10 includes a movement control unit 11, an illumination control unit 12, a shooting control unit 13, an image synthesis unit 14, and a determination unit 15. The movement control unit 11 through the determination unit 15 may be implemented by the processor 10 executing an information processing program stored in the memory 20, or they may be configured as dedicated hardware circuits such as an ASIC.

The movement control unit 11 controls the amount of movement of the inspection device 100. Specifically, the movement control unit 11 controls the rotation speed of the two motors included in the drive unit 3 individually by inputting a control signal to the drive unit 3. This rotates each wheel 2, moving the inspection device 100 forward or backward by a predetermined distance. The movement control unit 11 also stops the rotation of each wheel 2, thereby stopping the inspection device 100.

Furthermore, the movement control unit 11 controls the direction of movement of the inspection device 100. For example, the movement control unit 11 rotates the inspection device 100 and changes its direction of travel by stopping one of the motors included in the drive unit 3 and driving the other motor.

The movement control unit 11 moves the inspection device 100 along a predetermined movement route. The predetermined movement route is, for example, a route that covers the entire surface of the solar panel 50. In this embodiment, the movement control unit 11 generates a virtual map corresponding to the shape of the surface of the solar panel 50 in order to generate the predetermined movement route. The virtual map is, for example, a two-dimensional map defined by the X axis and the Y axis. The movement control unit 11 generates the virtual map by, for example, using VSLAM (Visual Simultanate Localization and Mapping) technology. Specifically, the manager of the inspection device 100 has the inspection device 100 perform a trial run. During this trial run, the inspection device 100 moves along the surface of the solar panel 50, photographs its surface, and estimates its own position. Furthermore, it maps its own position onto the virtual map. As a result, the movement control unit 11 generates a virtual map corresponding to the shape of the surface of the solar panel 50. Furthermore, the administrator may improve the accuracy of the map by inputting information that identifies the photograph taken at the starting point of the inspection device 100's movement. The movement control unit 11, having generated the virtual map, calculates a movement route covering the entire area of the virtual map using a predetermined route search algorithm.

However, the above process is merely an example, and the movement route can be determined by any appropriate method. For example, the administrator of the inspection device 100 may prepare data specifying the movement route in advance and input this data into the inspection device 100. Furthermore, the movement route does not necessarily need to cover the entire surface of the solar panel 50. For example, the movement control unit 11 may generate a movement route that covers only a portion of the surface of the solar panel 50.

The movement control unit 11 sets at least one shooting spot on the movement route. A shooting spot is a point where the shooting device 8 takes a photograph. There may be only one shooting spot on a single movement route, or there may be multiple shooting spots. For example, if a movement route is generated that covers the entire surface of the solar panel 50, the movement control unit 11 sets the shooting spots so that the entire surface of the solar panel 50 can be photographed. Specifically, the movement control unit 11 refers to the field of view information of the shooting device 8. The field of view information of the shooting device 8 is stored in the memory 20 in advance. Here, let's assume that the field of view (shooting range) of the shooting device 8 is 10 cm square. In this case, the movement control unit 11 sets the shooting spots on the movement route at 10 cm intervals. That is, the movement control unit 11 sets the shooting spots so that the inspection device 100 moves 10 cm, takes a photograph, moves another 10 cm, takes another photograph, and so on, repeating this operation. In this way, the inspection device 100 can photograph the entire surface of the solar panel 50. However, this is just one example, and the shooting locations can be determined using any appropriate method. For example, the location and number of shooting locations may be predetermined by the administrator of the inspection device 100.

The movement control unit 11 stops the inspection device 100 when it reaches the shooting spot while moving along the movement route. It then inputs a signal (hereinafter referred to as the arrival signal) to the lighting control unit 12 indicating that the inspection device 100 has reached the shooting spot. Furthermore, when the movement control unit 11 receives a signal (hereinafter referred to as the shooting completion signal) from the shooting control unit 13 indicating that the shooting of the inspection image has been completed, it restarts the inspection device 100.

The lighting control unit 12 controls the light intensity and color of the light emitted by the lighting device 7 by inputting control signals to the lighting device 7. When the lighting control unit 12 receives an arrival signal from the movement control unit 11, it inputs a control signal to the lighting device 7 to turn it on. This control signal includes instructions specifying the light intensity and color of the light emitted by the lighting device 7. Once the lighting device 7 is turned on, the lighting control unit 12 inputs a signal indicating that the lighting device 7 has been turned on (hereinafter referred to as the "on signal") to the imaging control unit 13. The lighting control unit 12 also inputs a signal indicating the color of the light emitted by the lighting device 7 (hereinafter referred to as the "color signal") to the imaging control unit 13. When the lighting control unit 12 receives a shooting completion signal from the imaging control unit 13, it turns off the lighting device 7. However, the lighting control unit 12 may keep the lighting device 7 lit while the inspection device 100 is moving across the surface of the solar panel 50.

The shooting control unit 13 controls the timing of the shooting device 8's shooting. Specifically, the shooting control unit 13, upon receiving the lighting signal and color signal from the lighting control unit 12, causes the shooting device 8 to photograph the solar panel 50. Once the shooting by the shooting device 8 is complete, the shooting control unit 13 inputs a shooting completion signal to the movement control unit 11.

The imaging control unit 13 acquires inspection images from the imaging device 8. During this process, the imaging control unit 13 generates various metadata. For example, the imaging control unit 13 generates metadata such as image ID, date and time of capture, and location information. This metadata is generated each time an inspection image is captured and is associated with the inspection image. The dataset of inspection images and the various metadata associated with them is stored in the memory 20.

The image ID is identification information used to identify the examination image.

The shooting date and time information indicates the year, month, day, and time the inspection image was taken. The shooting control unit 13 generates the shooting date and time information based on the current time measured by a clock (not shown) installed in the inspection device 100.

The shooting location information indicates the location where the inspection image was captured. The shooting location information includes coordinate values (X and Y coordinate values) on a virtual two-dimensional map corresponding to the shape of the solar panel 50. The shooting location information may also include the latitude and longitude of the shooting location. The latitude and longitude of the shooting location are measured, for example, by a position sensor such as a GPS sensor (not shown) provided by the inspection device 100.

The image synthesis unit 14 generates a composite image by combining multiple inspection images. The image synthesis unit 14 combines multiple inspection images based on the movement amount of the inspection device 100. The image synthesis unit 14 estimates the movement amount of the inspection device 100 by the following method.

(First Method) The image synthesis unit 14 acquires information indicating the rotation speed of the wheel 2 measured by the wheel sensor 4 (so-called odometry information) and information indicating the circumference of the wheel 2. Based on this information, it estimates the amount of movement of the inspection device 100. The information indicating the circumference of the wheel 2 is pre-stored in the memory 20.

(Second Method) The image synthesis unit 14 estimates the amount of movement of the inspection device 100 by utilizing processing performed by VSLAM technology, panoramic image synthesis technology, Visual Odometry technology, etc. Specifically, the image synthesis unit 14 first extracts a first feature point from the first inspection image, which is one of several inspection images generated when the shooting device 8 takes pictures at each shooting spot. The first feature point is, for example, a characteristic point on the outline of the solar panel 50 that is captured in the first inspection image. Next, the image synthesis unit 14 extracts a second feature point from the second inspection image, which is taken after the first inspection image. The second feature point is a point that corresponds to the first feature point. The image synthesis unit 14 extracts the second feature point by, for example, matching the first inspection image and the second inspection image. Having extracted the first and second feature points, the image synthesis unit 14 calculates the relative amount of movement of the second feature point with respect to the first feature point. Based on this relative movement, the image synthesis unit 14 estimates the movement of the inspection device 100.

The image synthesis unit 14 may combine the first and second methods described above. Specifically, it estimates the movement of the inspection device 100 (referred to as the first movement) using the first method. Then, it estimates the movement of the inspection device 100 (referred to as the second movement) using the second method. Finally, it corrects the first movement using the second movement. In this way, the image synthesis unit 14 can estimate the movement of the inspection image more accurately.

The image synthesis unit 14 synthesizes images based on the estimated amount of movement. For example, suppose the image synthesis unit 14 estimates that the inspection image moved 10 cm between the time the first inspection image was taken and the time the second inspection image was taken. In this case, the image synthesis unit 14 calculates the image displacement corresponding to the physical displacement of 10 cm and adjusts the position between the first and second inspection images based on this displacement. Through this position adjustment, the image synthesis unit 14 corrects the displacement between the images, seamlessly connecting the first and second inspection images to generate a composite image. While this example describes generating a composite image based on the first and second inspection images, the image synthesis unit 14 may generate a composite image based on more inspection images. That is, it may generate a composite image by connecting three or more inspection images together.

The determination unit 15 determines whether the solar panel 50 is malfunctioning based on at least one of at least one of the inspection image and at least one composite image. The detailed processing of the determination unit 15 will be described later.

Memory 20 consists of non-volatile, rewritable storage devices such as hard disk drives and solid-state drives.

The operation of the inspection device 100, which has the above configuration, will be explained with specific examples.

(First Example) The inspection device 100 according to the first example detects whether or not the solar panel 50 contains areas that have turned yellow. The solar panel 50 according to this embodiment (perovskite type solar panel) includes a light-absorbing layer (not shown). The light-absorbing layer mainly contains lead iodide, which is a compound of iodine and lead. Lead iodide has the property of turning yellow when it reacts with water. Generally, the light-absorbing layer is covered by a coating layer, so that water does not reach the light-absorbing layer and lead iodide does not react with water. However, if the coating layer deteriorates over time, water may penetrate the light-absorbing layer through the deteriorated parts of the coating layer. In this case, the lead iodide in the light-absorbing layer turns yellow and dissolves in water. As a result, areas that have turned yellow are formed on the solar panel 50. In addition, if silver is used for the electrodes of the solar panel 50, it may change to silver iodide (yellow). Hereafter, the phenomenon in which yellow discoloration forms on the solar panel 50 will be referred to as "yellowing."

Figures 4 and 5 are enlarged sections of the solar panel 50. More specifically, Figure 4 is an enlarged view of the area of the solar panel 50 where mild yellowing has occurred. Figure 5 is an enlarged view of the area of the solar panel 50 where severe yellowing has occurred. The solar panel 50 shown in Figure 4 includes a first section A1 and a second section A2. The first section A1 is the area where no yellowing has occurred. The second section A2 is the area where mild yellowing has occurred. In other words, the second section A2 is experiencing early-stage yellowing. The solar panel 50 shown in Figure 5 includes a third section A3, a fourth section A4, and a fifth section A5. The third section A3 is the area where yellowing has not progressed. The fourth section A4 is the area where moderate yellowing has occurred. In other words, the yellowing has progressed to the middle stage in the fourth section A4. The fourth section A4 has a weak (pale) yellow color, for example, orange. Section 5A5 is an area where severe yellowing has occurred. In other words, the yellowing in Section 5A5 has progressed to the final stage. Section 5A5 has a strong (deep) yellow color. Hereafter, the area of the solar panel 50 where yellowing has occurred will be referred to as the yellowed area.

The inspection device 100 according to the first example moves along a movement route under the control of the movement control unit 11. The movement route covers the entire surface of the solar panel 50. The inspection device 100 according to the first example moves across the entire surface of the solar panel 50 by performing a so-called zigzag movement. This zigzag movement involves repeatedly moving in a first direction (e.g., the longitudinal direction of the solar panel 50) and moving in a second direction perpendicular to the first direction (e.g., the short direction of the solar panel 50). As described above, the solar panel 50 according to this embodiment has a rectangular shape. Specifically, the inspection device 100 moves straight from one end of the solar panel 50 in the longitudinal direction towards the other end. Upon reaching the other end in the longitudinal direction, it moves slightly along the short direction (reversing direction) and then moves straight from the other end in the longitudinal direction towards the first end. The inspection device 100 repeats this zigzag movement until it has traversed the entire surface of the solar panel 50.

In the first example, the shooting spots are set at 10 cm intervals. Therefore, the inspection device 100 in the first example takes a photograph every 10 cm along its movement route. This shooting operation captures the entire surface of the solar panel 50.

In the first example, the lighting control unit 12 controls the light intensity of the lighting control unit 12 to a constant level when shooting is performed. Furthermore, the lighting control unit 12 controls the color of the light from the lighting device 7 to white. In other words, the lighting control unit 12 controls the lighting device 7 so that the solar panel 50 is illuminated with a constant light intensity and white light.

Once the lighting environment setting by the lighting control unit 12 is complete, the imaging device 8 photographs the surface of the solar panel 50. That is, the imaging device 8 photographs the surface of the solar panel 50 illuminated by white light and generates an inspection image. Hereinafter, the inspection image generated by photographing the surface of the solar panel 50 illuminated by white light will be referred to as a white inspection image. In the first example, the imaging device 8 performs one photograph per shooting spot, generating one white inspection image. The movement of the inspection device 100, illumination by the lighting device 7, and photography by the imaging device 8 are repeated until the entire surface of the solar panel 50 has been photographed.

The image synthesis unit 14 synthesizes (stitches together) multiple white inspection images generated by the imaging device 8 taking images at each shooting spot. Hereinafter, the composite image generated based on multiple white inspection images will be referred to as the white composite image. In the first example, the image synthesis unit 14 generates one composite image corresponding to one solar panel 50. That is, it generates a single composite image that captures the entire surface of one solar panel 50.

The determination unit 15 in the first example first detects (extracts) yellowed areas from the white composite image. A yellowed area is a portion of the white composite image that corresponds to a yellowed portion. In other words, it is the area where the yellowed portion is captured. As described above, the imaging device 8 in this embodiment is composed of an RGB camera. Therefore, each pixel constituting the white composite image is assigned an RGB value (an example of a pixel value). The determination unit 15 uses this RGB value to detect yellowed areas from the white composite image. Specifically, the determination unit 15 treats areas where the pixel value (RGB value) satisfies the following three yellowed area conditions as yellowed areas: (i) The R signal value is 200 or higher. (ii) The G signal value is 175 or higher. (iii) The B signal value is 150 or higher. Note that the numerical values for each condition from (i) to (iii) above are merely examples and can be changed as appropriate.

The determination unit 15, which detects (extracts) yellowed areas from the white composite image, calculates the area of the yellowed areas. Based on the area of the yellowed areas, the determination unit 15 then determines whether or not the solar panel 50 is malfunctioning.

When yellowing occurs, the power generation efficiency of the solar panel 50 decreases. Power generation efficiency is defined by the amount of electricity generated by the solar panel 50 per unit time. In the first example, the determination unit 15 determines that the solar panel 50 is faulty if its power generation efficiency is less than 50%, with the factory-shipped (new) solar panel 50's power generation efficiency being 100%.

There is a correlation between the proportion of the yellowed area in the white-based inspection image and the power generation efficiency of the solar panel 50. Specifically, the larger the yellowed area, the lower the power generation efficiency of the solar panel 50. To simplify the explanation, let's assume that a 1% increase in the proportion of the yellowed area corresponds to a 1% decrease in the power generation efficiency of the solar panel 50. In this case, the determination unit 15 determines whether the proportion of the yellowed area is 50% or more. If the proportion of the yellowed area is 50% or more, it considers the power generation efficiency of the solar panel 50 to be less than 50% and determines that the solar panel 50 is faulty. Note that the proportion of the yellowed area refers to the proportion of the yellowed area to the total surface area of the solar panel 50 as captured in the white-based composite image.

If the determination unit 15 determines that the solar panel 50 is malfunctioning, it generates a message notifying that the solar panel 50 is malfunctioning. The determination unit 15 then uses a communication module (not shown) provided in the inspection device 100 to transmit (output) this message to an information processing terminal, such as a smartphone or personal computer, owned by the administrator of the inspection device 100.

Furthermore, if the determination unit 15 determines that the solar panel 50 is not malfunctioning, it predicts when the solar panel 50 will malfunction (the remaining lifespan of the solar panel 50).

Assume that inspections by the inspection device 100 are performed regularly. For example, once a month, the inspection device 100 moves across the solar panel 50, takes pictures at each shooting spot, generates a composite image, and calculates the percentage of the yellowed area. Based on the information collected by the regular inspections by the inspection device 100, the determination unit 15 estimates the rate at which the yellowed area increases. For example, assume that one year after the installation of the solar panel 50 the percentage of the yellowed area is 10%. Then, assume that two years after the installation of the solar panel 50 the percentage of the yellowed area is 20%. Based on this data, the determination unit 15 estimates the rate at which the yellowed area increases. In this example, the determination unit 15 estimates that the yellowed area increases by 10% each year. Based on the estimated rate of increase and the current percentage of the yellowed area, the determination unit 15 predicts when the solar panel 50 will fail. Furthermore, the determination unit 15 may refer to various information such as sunshine duration and rainfall during the prediction process. The determination unit 15 transmits a message containing the above prediction results to the administrator's information processing terminal of the inspection device 100.

(Second Example) In the first example, the determination unit 15 determined whether the solar panel 50 was faulty without distinguishing between areas with severe yellowing (areas with a dark yellow color) and areas with moderate yellowing (areas with an orange color). The inspection device 100 in the second example distinguishes between these areas before determining whether the solar panel 50 is faulty.

The inspection device 100 in the second example moves along the solar panel 50, similar to the inspection device 100 in the first example, takes images at each shooting spot, and generates a single white composite image. This white composite image captures the entire surface of one solar panel 50.

The determination unit 15 in the second example identifies severe yellowing regions and moderate yellowing regions based on the pixel values (RGB values) of all pixels constituting the composite image.

The severe yellowing region is an area where the pixel value satisfies all of the following conditions (a) to (c): (a) The R signal value is 200 or higher. (b) The G signal value is 200 or higher. (c) The B signal value is 50 or higher and less than 150. The severe yellowing region corresponds to the part of the solar panel 50 where severe yellowing has occurred.

The moderate yellowing region is the area where the pixel values satisfy all of the following conditions (d) through (f): (d) The R signal value is 180 or greater and less than 200. (e) The G signal value is 150 or greater and less than 200. (f) The B signal value is 150 or greater. The moderate yellowing region corresponds to the part of the solar panel 50 where moderate yellowing occurs. Note that the numerical values for each condition from (a) to (f) are merely examples and can be changed as appropriate.

To simplify the explanation, let's assume the following: A 1% increase in the area of severely yellowed regions reduces the power generation efficiency of the solar panel 50 by 1%. Also, a 1% increase in the area of moderately yellowed regions reduces the power generation efficiency of the solar panel 50 by 0.5%.

Here, let X (%) be the percentage of the area of the severely yellowed region, and Y (%) be the percentage of the area of the moderately yellowed region. The determination unit 15 in the second example determines whether or not the solar panel 50 is malfunctioning using the following formula (F1).

X+Y×0.5>50...(F1)
The determination unit 15 determines that the solar panel 50 is faulty if the above formula (F1) is true. In other words, it determines that the power generation efficiency of the solar panel 50 is less than 50%. In this case, the determination unit 15 generates a message notifying that the solar panel 50 is faulty, similar to the determination unit 15 in the first example.

On the other hand, if the above equation (F1) does not hold true, the determination unit 15 determines that the solar panel 50 is not faulty. In this case, the determination unit 15 may predict the timing of the solar panel 50's failure, similar to the determination unit 15 in the first example.

(Third Example) The inspection device 100 in the third example generates a difference image based on an inspection image of the solar panel 50 irradiated with white light and an inspection image of the solar panel 50 irradiated with yellow light. Yellowing is detected based on this difference image.

The inspection device 100 in the third example takes two images at each shooting spot. During the first shooting, the lighting control unit 12 controls the lighting device 7 so that the solar panel 50 is illuminated with a constant amount of white light. The shooting control unit 13 causes the shooting device 8 to photograph the solar panel 50 illuminated with white light. That is, a white inspection image is generated. During the second shooting, the lighting control unit 12 controls the lighting device 7 so that the solar panel 50 is illuminated with the same amount of yellow light as in the first shooting. The shooting control unit 13 causes the shooting device 8 to photograph the solar panel 50 illuminated with yellow light. The inspection image generated by the second shooting is hereinafter referred to as the yellow inspection image. Note that when the yellowed area is illuminated with yellow light and photographed, an inspection image is generated in which the yellowed area stands out.

Except for the fact that the inspection image is captured twice, and that the solar panel 50 is illuminated with yellow light during the second capture, the processing of the movement control unit 11, illumination control unit 12, and image capture control unit 13 in the third example is the same as the processing of the movement control unit 11, illumination control unit 12, and image capture control unit 13 in the first example.

The image synthesis unit 14 in the third example generates two composite images. One of the two composite images is a white composite image. The white composite image captures the entire surface of one solar panel 50. The other of the two composite images is a composite image generated by stitching together multiple yellow inspection images. This composite image will be referred to as the yellow composite image below. The yellow composite image captures the entire surface of one solar panel 50.

In the third example, the determination unit 15 converts the white composite image and the yellow composite image to grayscale. Then, it generates a difference image based on the grayscaled white composite image and the yellow composite image. This generates an image in which the contrast between the yellowed region and the non-yellowed region is clearly defined. The determination unit 15 performs thresholding on this difference image. Specifically, it determines whether or not pixels with a brightness higher than a predetermined reference brightness are included in the difference image. If the determination unit 15 finds pixels with a brightness higher than the reference brightness (hereinafter referred to as yellowed-corresponding pixels) in the difference image, it determines that a yellowed area has formed on the solar panel 50. Next, the determination unit 15 calculates the total number of yellowed-corresponding pixels and the percentage of the total number of yellowed-corresponding pixels relative to all pixels in the difference image. If this percentage is 50% or more, the determination unit 15 determines that the power generation efficiency of the solar panel 50 is less than 50% and that the solar panel 50 is malfunctioning.

In the third example, the determination unit 15 may transmit the difference image to the administrator's information processing terminal of the inspection device 100. That is, an image in which the contrast between the areas where yellowing has occurred and the areas where yellowing has not occurred is clearly defined may be transmitted to the administrator's information processing terminal. This allows the administrator to clearly recognize the areas where yellowing has occurred. In this case, the determination unit 15 may perform a binarization process on the difference image using the above-mentioned reference brightness as a threshold. This allows the administrator to recognize the areas where yellowing has occurred even more clearly.

(Fourth Example) The inspection device 100 in the fourth example takes one inspection image at each shooting spot. At this time, the lighting control unit 12 controls the lighting device 7 to irradiate it with purple light. Then, the shooting control unit 13 causes the shooting device 8 to photograph the solar panel 50, which is irradiated with purple light. Purple is the complementary color of yellow. When the yellowed portion is photographed by the shooting device 8 while irradiated with purple light, the yellowed portion appears as black in the inspection image. That is, the yellowed portion is depicted by black pixels in the inspection image. The image synthesis unit 14 in the fourth example generates a composite image based on the multiple inspection images generated by taking images at each shooting spot. Then, the determination unit 15 in the fourth example detects the black pixels (pixels corresponding to the yellowed portion) in the composite image and determines whether the solar panel 50 is faulty based on the ratio of the total number of these black pixels to the total number of pixels in the composite image.

Except for the fact that the lighting device 7 irradiates the solar panel 50 with purple light, and the determination unit 15 determines whether or not the solar panel 50 is malfunctioning based on the total number of black pixels, the processing of the inspection device 100 according to the fourth example is the same as the processing of the inspection device 100 according to the first example.

(Example 5) In a perovskite-type solar panel 50, when inorganic materials dissolve, the brown areas may disappear, causing the color to lighten. The inspection device 100 in Example 5 irradiates the solar panel 50 with white light and determines whether the solar panel 50 is malfunctioning based on the change in the intensity of the brown color.

As the brown color of the area becomes lighter, the power generation efficiency of the solar panel 50 decreases. The power generation efficiency of the solar panel 50 can be calculated by multiplying the intensity of the brown color by a predetermined coefficient. This predetermined coefficient is calculated, for example, based on experimental data showing the correlation between the intensity of the brown color and power generation efficiency. The determination unit 15 determines that the solar panel 50 is malfunctioning if its power generation efficiency is, for example, less than 50%.

The inspection device 100 in the fifth example, similar to the inspection device 100 in the first example, moves along the solar panel 50 and illuminates the solar panel 50 with white light at each shooting spot provided on the solar panel 50. It generates one white inspection image for each shooting spot and combines multiple white inspection images to generate a single white composite image that captures the entire surface of one solar panel 50. Hereinafter, the composite image initially generated by the inspection device 100 will be referred to as the reference image.

The determination unit 15 in the fifth example extracts a brown region (an example of a specific region) from the reference image. The brown region is the area corresponding to the brown portion of the solar panel 50, and is the region where the pixel values (RGB values) satisfy all of the following conditions from (α) to (γ): (α) The R signal value is 120 or greater and 180 or less. (β) The G signal value is 60 or greater and 120 or less. (γ) The B signal value is 0 or greater and 50 or less. Note that these values are examples and can be changed as appropriate.

The inspection device 100 in the fifth example generates a composite image periodically (for example, every month). Hereinafter, the composite image generated after the generation of the reference image will be referred to as the progress image. The procedure for generating the progress image is the same as the procedure for generating the reference image. Each time a progress image is generated, the inspection device 100 performs a matching process between the progress image and the reference image, and extracts a corresponding region from the progress image. The corresponding region refers to the region in the progress image that corresponds to the brown region of the reference image. Having extracted the corresponding region from the progress image, the inspection device 100 converts the progress image to grayscale and calculates the average brightness of the corresponding region.

As described above, the power generation efficiency of the solar panel 50 can be calculated by multiplying the intensity of the brown color in the brown area by a predetermined coefficient. The current intensity of the brown color in the brown area of the solar panel 50 is represented by the average brightness of the corresponding region in the latest progress image. Therefore, the determination unit 15 estimates the current intensity of the brown color in the brown area of the solar panel 50 based on the average brightness of the corresponding region in the latest progress image. Then, the determination unit 15 calculates the power generation efficiency of the solar panel 50 by multiplying the estimated intensity of the brown color in the brown area by a predetermined coefficient. If the power generation efficiency is less than 50%, the determination unit 15 determines that the solar panel 50 is malfunctioning.

In addition, the determination unit 15 in the fifth example may determine that the solar panel 50 is malfunctioning if the average brightness of the corresponding area in the most recent progress image is less than a predetermined threshold (reference average brightness).

(Example 6) In Example 6, the imaging device 8 of the inspection device 100 captures inspection images at the same location at different times. Each time the imaging device 8 captures an image, the determination unit 15 detects the color intensity of a specific area in the inspection image and determines whether the solar panel 50 is malfunctioning based on the change in color intensity of that specific area.

Specifically, the inspection device 100 in the sixth example designates a predetermined position on the surface of the solar panel 50 as a periodic imaging spot. The periodic imaging spot is an imaging spot where periodic imaging is performed by the imaging device 8. The determination unit 15 determines whether or not the solar panel 50 is malfunctioning based on the color change in the inspection image captured at the periodic imaging spot.

The inspection device 100 sets a location where at least a portion of the brown area of the solar panel 50 can be photographed as a periodic shooting spot. In this case, the inspection device 100 moves to the same shooting location (periodic shooting spot) at the same time every day (for example, 12:00 p.m.), irradiates the solar panel 50 with a constant amount of white light, and generates one inspection image.

Furthermore, whether the inspection device 100 has reached the regularly scheduled shooting spot, that is, whether the inspection device 100 has accurately reached the same shooting location, can be determined by the inspection device 100 estimating its own position using the VSLAM technology described above. Additionally, by setting a fixed starting point for the inspection device 100's movement, the inspection device 100 can determine whether it has accurately reached the regularly scheduled shooting spot based on the amount and direction of movement from the starting point.

The inspection device 100 checks for changes in the color of the brown area based on inspection images taken at the regularly scheduled shooting spots. Specifically, each time the inspection device 100 generates an inspection image, it converts the image to grayscale and obtains the average brightness from the image. The inspection device 100 then determines that the solar panel 50 has malfunctioned if the average brightness of the inspection image falls below a predetermined standard average brightness. In other words, the inspection device 100 in the sixth example grasps the change in the color of the brown area by understanding the change in the average brightness of the inspection images taken at the regularly scheduled shooting spots. It then determines that the solar panel 50 has malfunctioned when the color of the brown area becomes lighter than a certain level.

The operation of the inspection device 100 in the first to sixth examples described above is merely one example. The inspection device 100 may determine whether or not the solar panel 50 is faulty in various ways other than those described above. Furthermore, the inspection device 100 may determine whether or not the solar panel 50 is faulty by appropriately combining some of the operations from the first to sixth examples described above.

As described above, the inspection device 100 according to this embodiment determines whether or not the solar panel 50 is faulty based on the inspection image generated by photographing the solar panel 50. In other words, the inspection device 100 determines whether or not the solar panel 50 is faulty based on its appearance. Therefore, even if the deterioration and fault of the solar panel 50 are not reflected in the temperature changes of the solar panel, it is possible to detect whether or not the solar panel is faulty.

Furthermore, the inspection device 100 according to this embodiment moves along the solar panel 50, reaches a predetermined shooting spot, and then performs the shooting. In other words, it photographs the solar panel 50 from a very close distance. This configuration allows for the generation of clearer inspection images compared to a case where a fixed-point camera is installed at a predetermined distance from the solar panel 50 and this fixed-point camera photographs part or all of the solar panel 50. Additionally, since the presence or absence of a fault is determined based on a clearer inspection image, the accuracy of fault detection is improved.

Furthermore, since the inspection device 100 according to this embodiment is configured to be self-propelled, it does not require large-scale equipment like the conventional technology. Specifically, the inspection device 100 is configured to be self-propelled by wheels 2 and a drive unit 3 that is driven according to the control of the movement control unit 11. Therefore, unlike the conventional technology, the inspection device 100 does not require large-scale equipment such as a pair of upper and lower clamping members and guide rails that span across the pair of clamping members. Consequently, cost reductions can be expected compared to the conventional technology.

(Embodiment 2)
The inspection device 100A according to Embodiment 2 further includes a cleaning mechanism 9. In Embodiment 2, the same reference numerals are used for components identical to those in Embodiment 1, and their descriptions are omitted.

Figure 6 is a block diagram showing the configuration of the inspection device 100A according to Embodiment 2. Figure 7 is a cross-sectional view of the inspection device 100A according to Embodiment 2. As shown in Figure 6, the inspection device 100A further includes a cleaning mechanism 9. The cleaning mechanism 9 mainly includes a wiping section 91 (Figure 7), a first tank (not shown), a supply passage, and a first pump.

The wiping section 91 (an example of a cleaning section) is located at the bottom of the main body 1 and cleans the surface of the solar panel 50. In this embodiment, the wiping section 91 is positioned to cover substantially the entire lower surface 1a of the main body 1. The wiping section 91 is made of, for example, a sponge. Note that the wiping section 91 does not necessarily have to be located at the bottom; its position can be changed as needed.

The first tank is a tank for storing the cleaning fluid supplied to the wiping section 91. The first tank is housed, for example, inside the main body 1.

The supply channel is located between the first tank and the wiping section 91. The cleaning fluid stored in the first tank is supplied to the wiping section 91 through the supply channel.

The first pump, for example, is positioned in the supply line and generates pressure to send the cleaning fluid stored in the first tank to the wiping unit 91.

The inspection device 100A according to Embodiment 2 cleans the solar panel 50 as it moves along it. Specifically, as the inspection device 100A moves along a predetermined route, the wiping section 91 of the cleaning mechanism 9 contacts the surface of the solar panel 50, wiping away dirt from its surface. This allows for simultaneous determination of whether the solar panel 50 is faulty and cleaning of its surface. The inspection device 100A according to Embodiment 2 is more efficient than performing the cleaning of the solar panel 50 surface and the inspection for faults separately and independently.

Furthermore, the cleaning mechanism 9 may further include various cleaning devices such as wipers and brushes.

(Embodiment 3)
As described above, yellowing occurs in part due to the deterioration of the coating layer, which allows moisture to penetrate the light-absorbing layer through the deteriorated portion. Therefore, when the inspection device 100B according to Embodiment 3 detects a yellowed portion, it applies a coating agent (an example of a repair agent) to the deteriorated portion of the coating layer to form a protective film. In this way, the inspection device 100B prevents further moisture from penetrating the light-absorbing layer and suppresses the progression of yellowing. In Embodiment 3, the same reference numerals are used for components that are the same as in Embodiment 1, and their descriptions are omitted.

Figure 8 is a block diagram showing the configuration of the inspection device 100B according to Embodiment 3. As shown in Figure 8, the inspection device 100B further includes a repair mechanism 30. The repair mechanism 30 includes a coating agent application section (an example of a repair agent application section), a second tank (an example of a repair agent storage section), a supply passage, a second pump, and a pressing section.

The coating application unit applies the coating agent supplied from the second tank to the surface of the solar panel 50. The coating application unit has a configuration similar to the wiping unit 91 according to Embodiment 2. That is, in this embodiment, the coating application unit is composed of a sponge positioned over substantially the entire lower surface 1a of the main body 1. However, the configuration of the coating application unit is not limited to this, and can be appropriately selected depending on the shape of the solar panel 50 and the type of coating agent.

The second tank stores the coating agent. A supply channel is interposed between the second tank and the coating agent application section. The coating agent stored in the second tank is supplied to the coating agent application section through the supply channel. A second pump, for example, is positioned in the supply channel to generate the pressure required to deliver the coating agent stored in the second tank to the coating agent application section.

The pressing section applies pressure to the coating agent application section with a predetermined force, thereby pressing the coating agent application section against the surface of the solar panel 50. This applies (adds) the coating agent to the surface of the solar panel 50. Once the coating agent is applied to the surface of the solar panel 50 and a protective film is formed, the protective film may obstruct the passage of light, potentially reducing the amount of light reaching the light absorption layer of the solar panel 50. Therefore, forming the protective film over an unnecessarily wide area may reduce the power generation efficiency of the solar panel 50. For this reason, it is desirable that the protective film be formed to cover only the deteriorated portion of the coating layer.

The inspection device 100B according to this embodiment applies the coating agent only to the deteriorated portion of the coating layer. Specifically, the inspection device 100B first determines whether or not yellowing has occurred on the solar panel 50. If yellowing is determined to have occurred, it identifies the location of the yellowing (for example, the coordinate value on a virtual two-dimensional map). The inspection device 100B identifies the location of the yellowing based, for example, on the position of pixels on the composite image (the coordinate value of the pixels on the composite image) of pixels whose pixel values satisfy the above-mentioned yellowing region conditions. Then, the inspection device 100B activates the pressing part only when passing over the location of the yellowing, pressing the coating agent application part against the surface of the solar panel 50 with a predetermined force. This allows the coating agent to be applied only to the deteriorated portion of the coating layer, forming a protective film. In this way, the progression of yellowing can be suppressed while preventing a decrease in the power generation efficiency of the solar panel 50. As a result, the durability of the solar panel 50 is improved.

The inspection device 100B according to this embodiment can repair deteriorated parts of the solar panel 50 while moving along the solar panel 50 to inspect whether or not the solar panel 50 is faulty. Therefore, it is more efficient compared to performing fault inspection and solar panel 50 repair separately and independently.

This disclosure may be modified as follows:

(1) The inspection device 100 may use image recognition technology such as pattern matching to determine whether or not yellowed areas are visible in the composite image. If it determines that yellowed areas are visible in the composite image, it may then determine that the solar panel 50 is malfunctioning.

(2) The determination unit 15 may identify the location of the yellowed area. For example, the location of the yellowed area may be identified based on the shooting location information attached to each inspection image. In this case, the determination unit 15 may generate a message including the result of identifying the fault location.

(3) In Embodiment 1, an example was described in which the solar panel 50 is determined to be faulty based on a composite image. However, the generation of a composite image is not essential. For example, the inspection device 100 may determine whether the solar panel 50 is faulty based on a single inspection image (for example, a single white inspection image).

(4) In Embodiment 1, an example was described in which a composite image is generated that captures the entire surface of one solar panel. However, the image synthesis unit 14 may generate multiple composite images that capture only a portion of the surface of the solar panel. For example, a composite image may be generated for each region (line) demarcated by the busbar electrodes. Based on these multiple composite images, it may be determined whether or not the solar panel is malfunctioning.

(5) In Embodiment 1, an example was described in which white, yellow, or purple light was irradiated onto the solar panel 50. However, various other colors of light may also be irradiated onto the solar panel 50. For example, the lighting device 7 may irradiate the solar panel 50 with red or blue light. The determination unit 15 may determine whether or not the solar panel 50 is malfunctioning based on an inspection image generated by photographing the solar panel 50 irradiated with red or blue light.

(6) In Embodiment 1, an example was described in which the lighting device 7 irradiates the solar panel 50 with visible light having a specific wavelength, such as white light or yellow light. However, the light irradiated by the lighting device 7 is not limited to visible light. For example, the lighting device 7 may irradiate the solar panel 50 with infrared light. In addition, ultraviolet light may be irradiated to the solar panel 50. The imaging device 8 may generate an inspection image by imaging the solar panel 50 irradiated with light such as infrared and ultraviolet light, and the determination unit 15 may determine whether or not the solar panel 50 is malfunctioning based on this inspection image.

(7) Perovskite-type solar panels may generate heat if the electrodes or electrical circuits deteriorate, making it difficult for electricity to flow through the cells. Therefore, the inspection device 100 may further include a thermographic camera. The inspection device 100 may determine whether or not there are areas on the solar panel 50 that are hotter than a predetermined reference temperature (heat-generating areas) by photographing the solar panel 50 using the thermographic camera. If areas hotter than the predetermined reference temperature are present, the inspection device 100 may determine that the solar panel 50 is faulty.

This disclosure is useful for detecting failures in solar panels.

1: Main body 1a: Bottom surface 2: Wheels 3: Drive unit 4: Wheel sensor 5: Attitude sensor 6: Suction mechanism 7: Lighting device (an example of a lighting unit)
8: Imaging device (an example of an imaging unit)
9: Cleaning mechanism 10: Processor 11: Movement control unit 12: Lighting control unit 13: Shooting control unit 14: Image synthesis unit 15: Judgment unit 20: Memory 30: Repair mechanism 50: Solar panel 91: Wiping unit 91 (Example of a cleaning unit)
100: Inspection device 100A: Inspection device 100B: Inspection device D: Recess L: Light

Claims (12)

An inspection device for perovskite-type solar panels,
Wheels and,
A movement control unit that controls the operation of the wheels,
The lighting unit that illuminates the aforementioned solar panel,
A camera unit that generates at least one inspection image by capturing a region illuminated by the illumination unit in the solar panel,
The system includes a determination unit that determines whether or not the solar panel is malfunctioning based on the aforementioned inspection image.
Inspection device. The imaging unit generates multiple inspection images,
The system further comprises an image synthesis unit that generates a composite image by combining the plurality of inspection images based on the amount of movement of the inspection device,
The determination unit determines whether or not the solar panel is malfunctioning based on the composite image.
The inspection apparatus according to claim 1. The aforementioned image synthesis unit,
A first feature point is extracted from the first inspection image among the aforementioned multiple inspection images.
A second feature point corresponding to the first feature point is extracted from a second inspection image taken after the first inspection image.
The amount of movement of the inspection device is estimated based on the first feature point and the second feature point.
The inspection apparatus according to claim 2. The system further includes a wheel sensor for measuring the rotation speed of the wheel,
The image synthesis unit estimates the amount of movement of the inspection device based on the rotation speed measured by the wheel sensor.
The inspection apparatus according to claim 2. The lighting unit irradiates the solar panel with white light,
The imaging unit generates a white inspection image, which is the inspection image generated by imaging the solar panel irradiated with the white light.
The determination unit,
Yellowed regions that satisfy the yellowed region conditions in terms of pixel values are detected from the white inspection image.
Based on the area of the yellowed region, it is determined whether or not the solar panel is malfunctioning.
The inspection apparatus according to any one of claims 1 to 4. The lighting unit irradiates the solar panel with white light,
The imaging unit generates multiple white inspection images by imaging the solar panel irradiated with the white light,
The image synthesis unit generates a white composite image by synthesizing the plurality of white inspection images.
The determination unit,
Yellow regions that satisfy the yellow region conditions in terms of pixel values are detected from the white composite image.
Based on the area of the yellowed region, it is determined whether or not the solar panel is malfunctioning.
The inspection apparatus according to any one of claims 2 to 4. The lighting unit irradiates the solar panel with white light and yellow light.
The aforementioned imaging unit is
The solar panel irradiated with the aforementioned white light is photographed to generate multiple white inspection images.
The solar panel illuminated by the aforementioned yellow light is photographed to generate multiple yellow inspection images.
The aforementioned image synthesis unit,
A white composite image is generated based on the aforementioned multiple white inspection images.
A yellow composite image is generated based on the aforementioned multiple yellow inspection images.
The determination unit,
A difference image is generated between the aforementioned white composite image and the aforementioned yellow composite image.
Based on the difference image, it is determined whether or not the solar panel is malfunctioning.
The inspection apparatus according to any one of claims 2 to 4. The determination unit determines whether or not the solar panel is malfunctioning based on the change in the color intensity of a specific region in the composite image.
The inspection apparatus according to any one of claims 2 to 4. The aforementioned imaging unit captures the inspection images at the same location at different times.
The determination unit,
Each time the imaging unit takes an image, the intensity of color in a specific area of the inspection image is detected.
Based on the change in the color intensity of the aforementioned specific area, it is determined whether or not the solar panel is malfunctioning.
The inspection apparatus according to any one of claims 1 to 4. The main body and
The system further comprises an adsorption mechanism located at the bottom of the main body, which adsorbs the main body onto the solar panel.
The inspection apparatus according to any one of claims 1 to 4. The main body and
The main body further comprises a cleaning unit located at the bottom of the main body for cleaning the surface of the solar panel.
The inspection apparatus according to any one of claims 1 to 4. The repair mechanism further includes a repair agent storage section for storing a repair agent, and a repair agent application section for applying the repair agent supplied from the repair agent storage section to the surface of the solar panel.
The inspection apparatus according to any one of claims 1 to 4.