A robot and a linear motion control method and data processing device thereof

Abstract

The present application discloses a robot and a method for controlling the straight-line movement thereof, which uses the real-time image acquired by the camera to locate the distance between the vehicle body and the edge of the photovoltaic panel array, and identifies the reference line in each frame of the real-time image through coordinate changes, calculates the real-time distance between the reference line and the origin, and determines whether the real-time distance is within a preset distance threshold range; at the same time, the real-time angle of the angle between the actual moving direction of the vehicle body and the preset direction is acquired, and determines whether the real-time angle is within a preset angle threshold range; when the real-time distance is outside the preset distance threshold range and the real-time angle is within the preset angle threshold range, the vehicle body is controlled to adjust the moving direction to the left or right until the distance difference is within the preset distance difference threshold range. Therefore, the robot walks in a straight line on the photovoltaic panel according to the preset route, and the recognition accuracy is high and the degree of automation is high.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent robots, and in particular to a robot and a linear motion control method thereof. Background Art

[0002] Solar energy is a renewable and clean energy source. Photovoltaic power generation technology is becoming more and more mature and has been widely used in countries around the world. However, the top surface of photovoltaic panels is prone to accumulation of dust, dirt and other dirt, which will seriously affect the efficiency and power generation. Therefore, there is a need for an automated device in the market to efficiently clean the panel surface.

[0003] Since the photovoltaic panel is an inclined plane, the dirt and dust generated after cleaning will slide down from top to bottom. Therefore, the best way to clean is to clean horizontally from top to bottom, row by row. During the cleaning process, it is necessary to ensure that every space on the panel surface is swept, leaving no dead corners, and to minimize the area that is repeatedly swept to improve work efficiency and reduce repeated work. Therefore, it is necessary to ensure that the robot can move in a straight line along the planned route without deviation.

[0004] Chinese patent (CN106325276B) discloses a method for determining and controlling a robot driving in a straight line on a slope plane, which compares the real-time direction data of an acceleration sensor with a standard direction database. The disadvantages of this method are that, first, the accuracy of the acceleration sensor is very high, resulting in high cost of the robot and lack of competitiveness; second, since the inclination angles of photovoltaic panels are not completely consistent, the inclination angles of different panel arrays in the same power station may be different, so each time the robot is placed on the panel array, the standard direction database needs to be reset, which is cumbersome to operate. Summary of the invention

[0005] The purpose of the present invention is to provide a robot and a linear motion control method thereof, so as to solve the technical problems existing in the prior art that the robot has high cost and is difficult to operate.

[0006] To achieve the above-mentioned purpose, the present invention provides a robot linear motion control method, comprising the following steps: a direction setting step, controlling a robot to move along a preset direction on a photovoltaic panel array; the robot comprises a vehicle body; an image acquisition step, acquiring real-time images on both sides of the vehicle body, wherein the display content of the real-time image is a part of the photovoltaic panel array; a coordinate transformation step, establishing a world coordinate system with the center point of the vehicle body as the origin, and performing coordinate transformation processing on each frame of the real-time image; a reference line identification step, identifying a reference line from each frame of the real-time image; and a reference line coordinate calculation step, calculating the coordinate of the reference line. A coordinate set of a straight line in a world coordinate system; a distance and angle comparison step, calculating the real-time distance between the reference line and the origin, and determining whether the real-time distance is within a preset distance threshold range; simultaneously obtaining the real-time angle of the angle between the actual moving direction of the vehicle body and the preset direction, and determining whether the real-time angle is within a preset angle threshold range; and a direction adjustment step, when the real-time distance is outside the preset distance threshold range and the real-time angle is within the preset angle threshold range, controlling the vehicle body to adjust the moving direction to the left or right until the distance difference is within the preset distance difference threshold range, and returning to the direction setting step.

[0007] Furthermore, the reference line identification step specifically includes the following steps: identifying at least one visible line segment from each frame of the real-time image, each visible line segment being an image of a frame of a photovoltaic panel in the real-time image; calculating the slope and position of the straight line where each visible line segment is located in the world coordinate system; selecting at least one straight line whose slope is within a preset slope range from the straight lines where the visible line segment is located as a candidate straight line; calculating the distance between each candidate straight line and the origin; and selecting at least one straight line that is closest to the origin from the candidate straight lines as a reference line.

[0008] Furthermore, in the reference line identification step, after the step of calculating the distance between each candidate straight line and the origin, the following step is also included: determining whether the distance between each candidate straight line and the origin is within a preset distance threshold range, and if not, filtering out the candidate straight line.

[0009] Furthermore, after the image acquisition step, the following step is also included: determining whether the brightness of the real-time image is less than a preset brightness threshold; if so, starting a fill light device and returning to the step of acquiring images on both sides of the vehicle body.

[0010] Furthermore, the direction adjustment step includes the following steps: obtaining a maximum threshold and a minimum threshold according to the preset distance difference threshold range; obtaining a camera number corresponding to a real-time picture showing the reference line; judging a relative position of the reference line and the vehicle body according to a relative position of the camera and the vehicle body; when the reference line is located on the left side of the vehicle body and the distance difference is greater than the maximum threshold, or when the reference line is located on the right side of the vehicle body and the distance difference is less than the minimum threshold, controlling the vehicle body to adjust its direction to the left; when the reference line is located on the right side of the vehicle body and the distance difference is greater than the maximum threshold, or when the reference line is located on the left side of the vehicle body and the distance difference is less than the minimum threshold, controlling the vehicle body to adjust its direction to the right.

[0011] To achieve the above-mentioned purpose, the present invention also provides a data processing device, including a memory for storing executable program code; and a processor, connected to the memory, for reading the executable program code to run a computer program corresponding to the executable program code, so as to execute the robot straight-line motion control method described above.

[0012] To achieve the above object, the present invention also provides a robot comprising the data processing device mentioned above.

[0013] Furthermore, the robot also includes a body capable of moving on the photovoltaic panel array; and cameras arranged on the left and right sides of the body; the lenses of the cameras are facing the photovoltaic panel array to capture images on both sides of the body; the data processing equipment is arranged in the body and connected to the cameras.

[0014] Furthermore, the robot also includes a fill light device connected to the data processing equipment; when the brightness of the image captured by the camera is less than or equal to a preset brightness threshold, the fill light device is activated.

[0015] Furthermore, the robot also includes a gyroscope connected to the data processing device, and the gyroscope is used to obtain the real-time moving direction of the vehicle body in real time.

[0016] Any of the above technical solutions has the following advantages or beneficial effects: providing a robot and a method for controlling straight-line movement thereof, using the real-time image acquired by the camera to locate the distance between the vehicle body and the edge of the photovoltaic panel array, and using the image recognition technology to identify the position of the reference line in each frame of the real-time image, with a high recognition accuracy of the reference line. The robot controls the vehicle body to move in a straight line on the photovoltaic panel array according to the relative position of the reference line and the vehicle body, and can automatically adjust the direction to return to the preset route when the vehicle body deviates from the preset route during the movement, with a high degree of automation.

[0017] When the reference line is located on the left side of the vehicle body and the distance difference is greater than the maximum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, or when the reference line is located on the right side of the vehicle body and the distance difference is less than the minimum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, the vehicle body is controlled to adjust its direction to the left so that the robot walks in a straight line on the photovoltaic panel according to the preset route.

[0018] When the reference line is located on the right side of the vehicle body and the distance difference is greater than the maximum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, or when the reference line is located on the left side of the vehicle body and the distance difference is less than the minimum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, the vehicle body is controlled to adjust its direction to the right, so that the robot walks in a straight line on the photovoltaic panel according to the preset route. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The technical solution and other beneficial effects of the present application will be made apparent by describing in detail the specific implementation methods of the present application in conjunction with the accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the structure of the robot moving on the photovoltaic panel array according to an embodiment of the present application.

[0021] Figure 2 This is a functional diagram of the robot according to an embodiment of the present application.

[0022] Figure 3 This is a structural schematic diagram of the robot from the first perspective of the embodiment of the present application.

[0023] Figure 4 This is a schematic diagram of the structure of the robot from a second perspective according to an embodiment of the present application.

[0024] Figure 5 This is a schematic diagram of the structure of the robot from a second perspective according to an embodiment of the present application.

[0025] Figure 6 This is a flow chart of the robot straight-line motion control method according to an embodiment of the present application.

[0026] Figure 7 This is a flowchart of the reference line identification steps of an embodiment of the present application.

[0027] Figure 8 This is a flow chart of the direction adjustment steps of an embodiment of the present application.

[0028] The components of the attached drawings are identified as follows:

[0029] 100. Robots; 200. Photovoltaic panel arrays;

[0030] 1. Vehicle body; 2. Camera;

[0031] 3. Fill light device; 4. Gyroscope;

[0032] 5. Positioning sensor; 6. Data processing equipment;

[0033] 20. Photovoltaic panel; 21. Upper edge line;

[0034] 22. Bottom line; 23. Left line;

[0035] 24, right line; 51, processor;

[0036] 52. Memory; 11. Motor;

[0037] 12. Nose; 13. Fuselage. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0039] like Figure 1 As shown, this embodiment provides a robot 100 for cleaning an inclined photovoltaic panel array 200, wherein the four edge lines of the photovoltaic panel array 200 include an upper edge line 21 and a lower edge line 22 parallel to each other, and a left edge line 23 and a right edge line 24 parallel to each other. Figure 1 As shown, the extension direction of the upper edge line 21 is the first direction x, and the extension direction of the left edge line 23 is the second direction y. The photovoltaic panel array 200 is an array-type planar structure composed of more than two photovoltaic panels 20. Each photovoltaic panel 20 is provided with an uninterrupted metal frame (not shown) at the edge. In this embodiment, the photovoltaic panel 20 is rectangular, and its four frames are made of aluminum alloy. The four edge lines of the photovoltaic panel array 200 are all composed of the frames of multiple photovoltaic panels arranged in the same straight line.

[0040] like Figure 2 As shown, the robot 100 includes a body 1, a camera 2, a fill light device 3, a gyroscope 4, a positioning sensor 5 and a data processing device 6, and the camera 2, the fill light device 3, the gyroscope 4 and the positioning sensor 5 are all connected to the data processing device 6.

[0041] like Figure 1-Figure 5As shown, the vehicle body 1 can travel on the photovoltaic panel array 200. The vehicle body 1 includes a motor 11, a head 12 and a body 13, wherein the motor 11 is installed in the head 12 or the body 13 to provide a power source, so that the robot 100 can move back and forth along the first direction x or the second direction y on the photovoltaic panel array 200. A cleaning part is provided at the front end or the rear end of the vehicle body 1. The cleaning part of this embodiment is preferably one or more roller brushes, and a controllable roller brush motor is provided in the vehicle body 1 to drive the roller brush to rotate.

[0042] Since the photovoltaic panel array is an inclined plane, the robot 100 is usually provided with an adsorption device on its bottom surface in order to improve its grip and prevent the robot 100 from sliding off the panel. However, there is usually a gap between two adjacent rows of panels. If the gap is always located below the robot 100 during the robot 100's walking process, the adsorption device will fail. Therefore, in order to prevent the robot 100 from sliding off, the robot 100 cannot move above the gap between two rows of panels when cleaning each row of photovoltaic panels.

[0043] During the cleaning process, dust, garbage and sewage will slide along the panel surface. In order to ensure the cleaning effect, the robot 100 should start from the lower left corner or lower right corner of the photovoltaic panel matrix, and drive straight from the lower end of the matrix to the upper end along the left line or right line of the photovoltaic panel matrix, and then move along the first direction x on the matrix, turn left or right at the edge of the matrix, and continue to move in the opposite direction along the first direction x on the matrix. The height of the robot 100 moving in the first direction x is lower than the height of its previous movement in the first direction x.

[0044] Before the robot 100 is placed on the photovoltaic panel array 200, the size of the photovoltaic panel array 200 is an unknown parameter for the robot 100. Due to the different sizes of the photovoltaic panel arrays 200, the robot 100 has different optimal routes on the panel array, and the number of turns on the same row of panels is also different, and its working mode is also different. The robot 100 needs to automatically calculate the size of each panel in the photovoltaic panel array during its movement, especially the length of each row of panels in its tilt direction, and calculate the number and distance that the robot 100 needs to reciprocate on each row of panels based on its size, and calculate the number and position of the robot 100's turn to ensure that every corner of each row of panels can be cleaned.

[0045] The panel array area that the vehicle body 1 passes through each time it moves in the first direction x can be defined as a cleaning channel. Each cleaning channel is equal to or less than the width of the cleaning part (roller brush). When the vehicle body 1 moves in a cleaning channel, its cleaning part (roller brush) may extend outside the cleaning channel.

[0046] At least one photovoltaic panel 20 in the same row can be divided into N cleaning channels extending in the first direction x, extending from the left side of the photovoltaic panel array 200 to the right side thereof, where N is the integer part of the quotient of the length of the photovoltaic panel 20 in this row on the inclined surface and the width of the cleaning portion plus one. For example, if the length of a row of panels is 2 meters, the width of the roller brush is 0.7 meters, and N is 3, then this row of panels needs to be divided into three horizontal cleaning channels, and the cleaning robot 100 can only sweep the entire row of panels after three reciprocating movements without leaving any dead corners. The three cleaning channels are the first channel, the second channel, and the third channel from top to bottom, and the widths of the three cleaning channels can be set to 0.7 meters, 0.6 meters, and 0.7 meters, respectively. When the vehicle body 1 is traveling in the second channel in the middle, the edges of its roller brush at both ends will extend into the first channel and the third channel.

[0047] In this solution, when the vehicle body is traveling in a straight line in a certain cleaning channel, how to ensure that the vehicle body 1 does not deviate from its preset direction during travel is a key technical issue.

[0048] The camera 2 is arranged on the outer side walls on the left and right sides of the vehicle body 1, and the lens of the camera 2 faces the photovoltaic panel array 200 to collect images on both sides of the vehicle body 1. The camera 2 located on the left side of the vehicle body 1 is a left camera 201, and the camera 2 located on the right side of the vehicle body 1 is a right camera 202.

[0049] The positioning sensor 5 is arranged on the left and right sides of the vehicle body 1 and fixed to the bottom of the vehicle body, or one end of the positioning sensor 5 is fixed to the side wall of the vehicle body 1 and the other end of the positioning sensor 5 extends to the bottom of the vehicle body 1; each positioning sensor 5 is located in the same straight line with a camera 2. Among them, the positioning sensor 5 located on the left side of the vehicle body 1 is the left positioning sensor 501, and the positioning sensor 5 located on the right side of the vehicle body 1 is the right positioning sensor 502. The left and right positioning sensors are metal sensors 5, which establish communication connection with the data processing device 6. The metal sensor 5 is used to detect metal substances within a certain distance, and has the characteristics of a small detection range and high sensitivity. The general detection range is tens of millimeters.

[0050] When the distance between the metal sensor 5 and the metal frame is less than a preset threshold value (in this embodiment, the preset threshold value is 2.5 cm), an electrical signal is generated and sent to the data processing device 6. In this embodiment, the vertical distance between the metal sensor 5 and the photovoltaic panel 20 is about 2 cm, that is, when the metal sensor 5 is located directly above the metal frame, the projection of the metal sensor 5 on the photovoltaic panel is located on the metal frame, and an electrical signal can be generated in the metal sensor 5.

[0051] The robot 100 is initially placed at the lower left corner or lower right corner of the photovoltaic panel array. When the vehicle body is started for the first time, the vehicle body should move in a straight line along the second direction y, and the metal sensor 55 on the left or right side of the vehicle body is always located directly above the left line or right line where the multiple metal frames of the photovoltaic panel array are located.

[0052] When the vehicle body 1 drives to the upper edge or lower edge of the photovoltaic panel array 200, the vehicle body 1 automatically turns or makes a U-turn and moves in a straight line along the first direction x. The metal sensor 5 on the left or right side of the vehicle body 1 is always located directly above the metal frame of the upper edge or lower edge of the photovoltaic panel array 200.

[0053] Although there are gaps between the multiple photovoltaic panels 20 in the photovoltaic panel array 200, the gap width is small, and even if the metal sensor 5 is located directly above the gap, it can sense the metal frames on both sides of the gap. Therefore, as long as the vehicle body 1 moves in a straight line along the edge of the photovoltaic panel array at the edge of the array, there is always a metal frame within the sensing range of the metal sensor 5, and the metal sensor 5 will continue to generate an electrical signal.

[0054] When the vehicle body 1 deviates from its preset traveling direction, the projection of the metal sensor 5 on the top surface of the photovoltaic panel 20 is outside the metal frame, and there is no metal in the effective sensing range of the metal sensor 5, so the metal sensor 5 cannot generate an electrical signal. The data processing device 6 includes a control system of the robot 100, which monitors whether the vehicle body 1 moves along a straight line according to the real-time signal of the metal sensor 5, and determines in real time whether the vehicle body 1 deviates during travel. When it deviates, it adjusts the direction appropriately to return it to the original travel route.

[0055] The above method is only suitable for the case where the robot 100 walks in a straight line along the edge of the photovoltaic panel array 200. If the robot 100 needs to move in the middle of the photovoltaic panel array 200, the metal sensors 5 on its left and right sides cannot be located directly above the metal frame. At this time, it is necessary to find at least one other straight line for the robot 100 as a reference line.

[0056] When the robot 100 moves in the middle of the photovoltaic panel array 200, the two cameras on its left and right sides can collect images of one or two photovoltaic panel array edges in real time. The data processing device 6 uses a suitable algorithm to perform coordinate transformation processing on the edge images in the real-time picture, so that when the robot 100 moves, the real-time distance between the center point of the vehicle body 1 and the edge is obtained in real time. The edge of the photovoltaic panel array is used as a reference line to determine whether the distance between the vehicle body 1 and the reference line is constant. If it is constant, it means that the vehicle body 1 is moving in a straight line along the preset direction. If it increases or decreases, the data processing device 6 can control the vehicle body 1 to appropriately adjust its moving direction.

[0057] In this embodiment, during the process of cleaning the photovoltaic panel 20, the camera 2 or the positioning sensor 5 can be used alone to determine whether the vehicle body 1 deviates from the preset route. Of course, the camera 2 and the positioning sensor 5 can also be used simultaneously.

[0058] The robot 100 provided in this embodiment collects images of both sides of the vehicle body 1 in real time through the camera 2, and performs coordinate transformation processing on each frame of real-time image by means of coordinate transformation, so as to convert the coordinates of the edge line of the photovoltaic panel array in the image into coordinates in the world coordinate system, and then obtain the distance between the vehicle body 1 and the edge line of the photovoltaic panel array 200 on its left and right sides, so that the robot 100 can keep walking in a straight line on the photovoltaic panel 20 according to the preset route.

[0059] When at least one photovoltaic panel 20 in the same row can be divided into three or more cleaning channels extending in the first direction, the robot 100 needs to move back and forth horizontally on the photovoltaic panel array 200 in the row for more than three times.

[0060] Specific, combined Figure 1 As shown, when the robot 100 moves along the first direction x to clean the photovoltaic panel array 200, the robot 100 is close to the upper metal frame and the lower metal frame of the photovoltaic panel 20, that is, the robot 100 is located in the first cleaning channel and the last cleaning channel of the photovoltaic panel 20, and the position of the vehicle body 1 on the photovoltaic panel array 200 can be obtained in real time through the positioning sensor 5; when the robot 100 is located in other cleaning channels, the image of both sides of the vehicle body 1 can be collected in real time through the camera 2, so as to obtain the position of the vehicle body 1 on the photovoltaic panel array 200 in real time. Of course, in the process of cleaning the entire photovoltaic panel array 200, the robot 100 can only use the camera 2 without the positioning sensor 5 to obtain the position of the vehicle body 1 on the photovoltaic panel array 200 in real time. In theory, the robot 100 can ensure that it moves in a straight line by finding a reference line. The reference line can be collected by the camera or by the metal sensor 5. Considering the accuracy of image recognition and metal recognition, two reference lines can also be used to correct the direction at the same time to improve the accuracy and reduce the recognition error.

[0061] When the sun is bright during the day, the photovoltaic panel array 200 needs to operate normally. The panel cleaning work of the robot 100 will affect the power generation efficiency of the photovoltaic panel array 200 to a certain extent. Therefore, the cleaning work of the photovoltaic panel can also be completed at night, but the surface light of the panel array 200 is insufficient at night, which will affect the brightness of the panel image collected by the camera 2. If the image brightness is insufficient, the accuracy of image recognition will be affected, and the straight-line movement of the vehicle body cannot be guaranteed. For this reason, two fill light devices 3 are specially set in this embodiment, which are respectively located next to the two cameras 2 and their directions are consistent with the direction of the camera 2.

[0062] When the brightness of the image collected by the camera 2 is less than or equal to a preset brightness threshold, the data processing device 6 issues a control instruction to start the fill light device 3; conversely, when the brightness of the image is greater than the preset brightness threshold, the fill light device 3 does not need to be started. The fill light device 3 is a flashlight, and the user can judge whether the fill light device 3 is in a working state according to whether the fill light device 3 is flashing. If the fill light device 3 is in a flashing state, it means that the fill light device 3 is in a working state; if the fill light device 3 is in no state, it means that the fill light device 3 is in a shutdown or standby state. Therefore, the fill light device 3 can well solve the problem that the robot 100 cannot walk in a straight line on the photovoltaic panel array 200 in a low-light environment, so that the robot 100 can work normally at night.

[0063] The gyroscope 4 is arranged in the vehicle body 1 to obtain the real-time direction of the vehicle body 1, that is, the direction of the front of the vehicle, and can transmit the real-time angle of the vehicle body 1 to the data processing device 6. The gyroscope 4 can be a fiber optic gyroscope or a laser gyroscope. In this embodiment, in addition to using the gyroscope 4 to obtain the real-time direction of the vehicle body 1, other sensors can also be used instead, as long as the real-time direction of the vehicle body 1 can be obtained and the real-time angle of the vehicle body 1 can be transmitted to the data processing device 6, and no special limitation is made here.

[0064] The data processing device 6 is disposed in the vehicle body 1, and includes a memory 52 and a processor 51. Specifically, the memory 52 is used to store executable program codes. The processor 51 is connected to the memory 52, and runs a computer program corresponding to the executable program code by reading the executable program code, so as to execute the robot 100 straight line travel control method mentioned below.

[0065] The robot 100 provided in this embodiment uses a camera to obtain real-time images on both sides of the vehicle body 1, and uses the real-time image to locate the distance between the vehicle body 1 and the edge of the photovoltaic panel, thereby performing data fusion with the real-time angle obtained by the gyroscope, that is, by calculating the real-time distance between the reference line and the origin in each frame of the real-time image, and simultaneously obtaining the real-time angle of the angle between the time travel direction of the vehicle body 1 and the preset direction, when the real-time distance is outside the preset distance threshold range and the real-time angle is within the preset angle threshold range, the vehicle body is controlled to adjust the travel direction to the left or right until the distance difference is within the preset distance difference threshold range, thereby ensuring that the robot 100 can keep walking in a straight line along the preset route on the photovoltaic panel array 200.

[0066] like Figure 6 As shown, this embodiment provides a linear motion control method for the robot 100 mentioned above, comprising the following steps S1)-S8).

[0067] S1) direction setting step, controlling a robot 100 to move along a preset direction on a photovoltaic panel array 200; the robot 100 includes a body 1, and cameras 2 are provided on its left and right sides, facing the photovoltaic panel array 200 so that the edge of the array can be photographed.

[0068] Combination Figure 1 As shown, the robot 100 walks along a first direction x on a photovoltaic panel array 200, the left camera 201 is arranged on a side of the vehicle body 1 close to the upper edge line 21, and the right camera 202 is arranged on a side of the vehicle body 1 away from the upper edge line 21. When the robot 100 is moving, the gyroscope 4 is used to obtain the real-time moving direction of the vehicle body 1 in real time.

[0069] S2) an image acquisition step, acquiring real-time images of both sides of the vehicle body 1 , wherein the display content of the real-time image is a part of the photovoltaic panel array 200 .

[0070] Specifically, the left camera 201 obtains the real-time image of the left side of the vehicle body 1, and the right camera 202 obtains the real-time image of the right side of the vehicle body 1, and the left camera 201 and the right camera 202 transmit the obtained real-time images to the output processing device.

[0071] S3) determining whether the brightness of the real-time image is less than a preset brightness threshold; if so, S9) starting the fill light device 3 and returning to the step of acquiring images on both sides of the vehicle body 1.

[0072] Specifically, the output processing device performs a model change on the acquired real-time image, and then determines whether the brightness of the real-time image is within a set threshold range. If the brightness of the real-time image is less than a preset brightness threshold, it is necessary to start the fill light device 3 set on the vehicle body 1, otherwise, the next step is executed. The fill light device 3 can well solve the problem that the robot 100 cannot walk in a straight line on the photovoltaic panel array 200 in a low-light environment.

[0073] S4) coordinate transformation step, taking the center point of the vehicle body 1 as the origin, establishing a world coordinate system, performing coordinate transformation processing on each frame of the real-time image, and obtaining image parameters that are basically consistent with the scene on the top surface of the panel array 200, that is, world coordinates.

[0074] Specifically, from the perspective transformation formula we can know:

[0075]

[0076] Where u, v, w are the original image coordinates, and x', y', w' are the corresponding transformed image coordinates. u and x' are the distances in the first direction x, v and y' are the distances in the second direction y, and w and w' are the distances in the third direction z, where the third direction z is perpendicular to the first direction x and the second direction y.

[0077] The formula for the equation of a line is: A*x+B*y+C=0, where A and B are not all zero, and the coordinates of point P are (x0, y0), then the distance from the point to the line is:

[0078]

[0079] Therefore, based on the real-time images collected by the cameras 201 on the left and right sides of the vehicle body 1, and through the above-mentioned perspective transformation formula, a world coordinate system is established with the center point of the vehicle body 1 as the origin, and each frame of real-time image is transformed into an image in the world coordinate system. After the transformation, the distance between each pixel point in the image and the image origin is the real physical distance in the world coordinate system.

[0080] S5) Reference line identification step, identifying the reference line from each frame of the real-time image, and finding the coordinates of each pixel point on the reference line in the world coordinate system from the image parameters after coordinate transformation of each frame. In the real-time image of the photovoltaic panel array 200, the photovoltaic panel 202 is generally dark in color, such as black, dark blue or dark gray, and the panel frame is generally made of silver-white aluminum alloy. The contrast in the image is very clear, but because the frame has a certain width, the two side lines of the frame are the inner side line and the outer side line, respectively. The inner side line directly connected to the top surface of the photovoltaic panel 20 is preferably used as the reference line to improve the accuracy of recognition.

[0081] S6) A reference line coordinate calculation step, calculating the coordinate set of the straight line where the reference line is located in the world coordinate system, and finding the coordinate set of the straight line where the reference line is located in the world coordinate system from the image parameters after the coordinate transformation of each frame.

[0082] S7) a distance and angle comparison step, calculating the real-time distance between the reference line and the origin, and determining whether the real-time distance is within a preset distance threshold range; and simultaneously obtaining the real-time angle of the angle between the actual moving direction of the vehicle body 1 and the preset direction, and determining whether the real-time angle is within a preset angle threshold range.

[0083] Specifically, during the working process, the robot 100 uses the gyroscope 4 to obtain the real-time forward direction of the vehicle body 1, that is, the direction of the vehicle head, and compares this direction with the preset direction, thereby obtaining the real-time angle of the angle between the actual forward direction of the vehicle body 1 and the preset direction (that is, the real-time angle of the gyroscope), and judges whether the real-time angle is within a preset angle threshold range. When the real-time angle is within the preset angle threshold range, it means that the real-time forward direction of the vehicle body 1 has not deviated, and there is no need to adjust the direction of the vehicle body 1. When the real-time angle is not within the preset angle threshold range, it means that the real-time forward direction of the vehicle body 1 has deviated, and the direction of the vehicle body 1 needs to be adjusted (that is, enter the next step). In the process of adjusting the real-time forward direction of the vehicle body 1, the real-time forward direction of the vehicle body 1 may also deviate from the previously preset route, such as moving up or down as a whole. At this time, the distance between the vehicle body 1 and the reference lines on both sides is different from the original. Therefore, it is necessary to calculate the real-time distance between the reference line and the origin, and judge whether the real-time distance is within a preset distance threshold range. When the real-time distance is within a preset distance threshold range, it means that the real-time forward direction of the vehicle 1 does not deviate from the previously preset route. When the real-time distance is not within a preset distance threshold range, it means that the real-time forward direction of the vehicle 1 deviates from the previously preset route, and the real-time distance from the vehicle 1 to the reference lines on both sides and the origin needs to be adjusted (i.e., proceed to the next step).

[0084] S8) A direction adjustment step, determining in real time whether the real-time angle is within a preset angle threshold range, and determining in real time whether the real-time distance is within a preset distance threshold range.

[0085] When the real-time angle is outside the preset angle threshold range, it means that the vehicle body 1 has seriously deviated from the preset direction, which may be caused by a large-scale skidding accident of the vehicle body 1. It is necessary to control the vehicle body 1 to adjust the travel direction to the left or right so that its travel direction is consistent with the preset direction, so that the real-time angle is within the preset angle threshold range. In some embodiments, it is also possible to first determine whether the position of the vehicle body 1 is within the preset cleaning channel. If not, adjust the vehicle body 1 back to its preset route and back to the position before the skidding accident occurred; then control the vehicle body 1 to adjust the travel direction to the left or right so that its travel direction is consistent with the preset direction.

[0086] When the real-time distance is outside the preset distance threshold range and the real-time angle is within the preset angle threshold range, it means that the vehicle body 1 has deviated as a whole, but the direction of the front of the vehicle is basically correct. The vehicle body 1 is controlled to adjust the direction of travel to the left or right until the distance difference is within the preset distance difference threshold range, and the direction setting step S1 is returned). For example: in the process of the vehicle body moving horizontally from the right line of the photovoltaic panel array to the left line in the first direction x, the left camera 201 detects the first distance between the vehicle body and the lower line in real time, and the right camera detects the second distance between the vehicle body and the upper line in real time. If the vehicle body has been moving in a straight line in the first direction, the first distance and the second distance are only within the preset distance threshold range. If the first distance increases and the second distance decreases, it means that the vehicle body is biased to the right and needs to be adjusted to the left. The data processing device issues an instruction to control the vehicle body to turn left. When the first distance and the second distance return to the preset distance threshold range, the direction is adjusted again to control the vehicle body to move along the preset direction. Similarly, if the first distance becomes smaller and the second distance becomes larger, it means that the vehicle body is biased to the left and needs to be adjusted to the right. The data processing device sends an instruction to control the vehicle body to turn right. When the first distance and the second distance return to the preset distance threshold range, the direction is adjusted again to control the vehicle body to move along the preset direction.

[0087] When the real-time distance is within the preset distance threshold range and the real-time angle is within the preset angle threshold range, it means that the vehicle body 1 has not deviated and the vehicle head direction is basically correct. No direction adjustment is required, and the process returns to the direction setting step S1).

[0088] like Figure 7 As shown, S5) the reference line identification step specifically includes the following steps:

[0089] S501) Identify at least one visible line segment from each frame of the real-time image, each visible line segment is an image of the frame of a photovoltaic panel 20 in the real-time image. The photovoltaic panel is dark, and the panel frame is silvery white. After the image is binarized, the visible line segment corresponding to the panel frame is very clear. Since the frame has a certain width, the two side lines of the frame are the inner side line and the outer side line, and the inner side line directly connected to the top surface of the photovoltaic panel is preferably used as the reference line, and the color difference between the two is more obvious, so as to improve the accuracy of recognition.

[0090] S502) Calculate the slope and position of the straight line where each visible line segment is located in the world coordinate system.

[0091] Specifically, the data processing device 6 calculates the straight line on which each visible line segment is located according to the straight line equation The slope and position of the straight line where each visible line segment is located in the world coordinate system are obtained. Within the field of view of a camera, the frames of the photovoltaic panel array 200 in four directions are clearly visible. Therefore, in this step, the data processing device 6 can identify at least one panel frame at two edge lines parallel to the extension direction of the left and right side walls of the vehicle body 1 through the camera, and can also identify part of the panel frame at two edge lines perpendicular to the extension direction of the left and right side walls of the vehicle body 1. For example: when the vehicle body 1 is moving horizontally from the right line to the left line of the photovoltaic panel array 200 in the first direction x, the left camera 201 collects the lower line image of the photovoltaic panel array 200 in real time, and the right camera 202 collects the upper line image of the panel array 200 in real time. However, both the left camera 201 and the right camera 202 can collect partial images of the left and right lines of the photovoltaic panel array 200.

[0092] S503) At least one straight line with a slope within a preset slope range is selected from the straight lines where the visible line segment is located as a candidate straight line. The reference lines described in this embodiment are two side lines parallel to the extension direction of the left and right side walls of the vehicle body. The two side lines perpendicular to the extension direction of the left and right side walls of the vehicle body cannot be used as reference lines, so they must be selected to eliminate interference. The preset slope range is a slope range with a deviation of about 3-5% in both positive and reverse directions, with the slope of the straight line parallel to the extension direction of the left and right side walls of the vehicle body 1 as the center number.

[0093] S504) Calculate the distance between each candidate straight line and the origin.

[0094] Specifically, the distance between each candidate straight line and the origin is calculated by the data processing device 6. Since the vehicle body 1 has a certain size and the origin is the center point of the vehicle body 1, the distance between the candidate straight line and the origin can be defined as the distance between the vehicle body 1 and the candidate straight line.

[0095] S505) Determine whether the distance between each candidate straight line and the origin is within the preset distance threshold range. If not, S507) filter out the candidate straight line. In a photovoltaic power station, in order to improve space utilization, the distance between multiple photovoltaic panel 20 matrices will be relatively close. In the field of view of the camera, in addition to the image of the frame of the photovoltaic panel matrix where the vehicle body 1 is located, partial images of the frames of other photovoltaic panel matrices may also be displayed. These frames can also be identified as candidate straight lines, but these frames are sometimes not captured when the vehicle body 1 is moving. Their extension direction and distance from the vehicle body 1 do not have much reference value for the vehicle body 1, so they should be deleted. If there are light-colored debris in the shape of a straight line on the photovoltaic panel array 200, it may also be identified as a candidate straight line, but its extension direction has no reference value and should also be deleted to eliminate interference.

[0096] S506) At least one straight line closest to the origin is selected from the candidate straight lines as a reference line. After all straight lines that may cause interference are removed in step S505), the remaining candidate straight lines are only the inner and outer edges of the two frames parallel to the extension direction of the left and right side walls of the vehicle body 1. There may be other background patterns near the outer edges. The inner edge directly connected to the photovoltaic panel 20 is preferred, with obvious contrast and clear boundaries.

[0097] like Figure 8 As shown, S8) the direction adjustment step includes the following steps:

[0098] S801) Obtaining a maximum threshold and a minimum threshold according to the preset distance difference threshold range.

[0099] S802) Obtain the camera number corresponding to the real-time image showing the reference line, the left camera 201 or the right camera 202. Specifically, number each camera 2 corresponding to the real-time image showing the reference line, and determine whether the camera photographing the reference line is on the left side or the right side of the vehicle body.

[0100] S803) According to the relative position of the camera and the vehicle body, the relative position of the reference line and the vehicle body 1 is determined, and it is determined whether the real-time image showing the reference line is on the left side or the right side of the vehicle body.

[0101] If the reference line is located on the left side of the vehicle body 1,

[0102] S811) determines whether the distance difference is greater than the maximum threshold, if so, S812) adjusts the direction to the left; if not, S813) determines whether the distance difference is less than the minimum threshold, if so, S814) adjusts the direction to the right; if not, S815) does not adjust the direction.

[0103] If the reference line is located on the right side of the vehicle body 1,

[0104] S821) determines whether the distance difference is greater than the maximum threshold, if so, S822) adjusts the direction to the right; if not, S823) determines whether the distance difference is less than the minimum threshold, if so, S824) adjusts the direction to the left; if not, S825) does not adjust the direction.

[0105] Therefore, by adjusting the above steps, the robot 100 can maintain walking in a straight line within the preset walking threshold range.

[0106] The above steps S811-814 and steps S821-824 are executed synchronously, and in other embodiments, they can also be executed sequentially. Step S811 and step S813 are executed sequentially, and in other embodiments, they can also be executed synchronously. Step S821 and step S823 are executed sequentially, and in other embodiments, they can also be executed synchronously.

[0107] The straight-line motion control method of the robot 100 provided in this embodiment uses the real-time image acquired by the camera to locate the distance between the vehicle body 1 and the edge of the photovoltaic panel array 200, and identifies the reference line in each frame of the real-time image through coordinate changes.

[0108] When the reference line is located on the left side of the vehicle body 1 and the distance difference is greater than the maximum threshold, and the real-time angle of the gyroscope 4 is within the preset angle threshold range, or when the reference line is located on the right side of the vehicle body and the distance difference is less than the minimum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, the vehicle body 1 is controlled to adjust its direction to the left.

[0109] When the reference line is located on the right side of the vehicle body and the distance difference is greater than the maximum threshold, and the real-time angle of the gyroscope is within the preset angle threshold range, or when the reference line is located on the left side of the vehicle body and the distance difference is less than the minimum threshold, and the real-time angle of the gyroscope 4 is within the preset angle threshold range, the vehicle body is controlled to adjust its direction to the right.

[0110] Therefore, the robot 100 walks in a straight line on the photovoltaic panel 20 according to a preset route, with high recognition accuracy and high degree of automation.

[0111] The above is a detailed introduction to a robot and a linear motion control method thereof provided in an embodiment of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solution and core idea of ​​the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present application.

Claims

1. A robot linear motion control method, characterized in that: The steps include: A direction setting step, controlling a robot to move along a preset direction on a photovoltaic panel array; the robot comprises a vehicle body; An image acquisition step, acquiring real-time images of both sides of the vehicle body, wherein the display content of the real-time image is a part of the photovoltaic panel array; A coordinate transformation step, taking the center point of the vehicle body as the origin, establishing a world coordinate system, and performing coordinate transformation processing on each frame of the real-time image; A reference line identification step, identifying a reference line from each frame of the real-time image; The reference line identification step specifically includes the following steps: Identify at least one visible line segment from each frame of the real-time image, each visible line segment being an image of a frame of a photovoltaic panel in the real-time image; Calculate the slope and position of the straight line of each visible line segment in the world coordinate system; Selecting at least one straight line whose slope is within a preset slope range from the straight lines where the visible line segment is located as a candidate straight line; Calculate the distance between each candidate straight line and the origin; Selecting at least one straight line which is closest to the origin from the candidate straight lines as a reference line; A reference line coordinate calculation step, calculating a coordinate set of the straight line where the reference line is located in the world coordinate system; The distance and angle comparison step calculates the real-time distance between the reference line and the origin, and determines whether the real-time distance is within a preset distance threshold range; at the same time, obtains the real-time angle of the angle between the actual moving direction of the vehicle body and the preset direction, and determines whether the real-time angle is within a preset angle threshold range; as well as a direction adjustment step, when the real-time distance is outside the preset distance threshold range and the real-time angle is within the preset angle threshold range, controlling the vehicle body to adjust the travel direction to the left or right until the distance difference is within the preset distance difference threshold range, and returning to the direction setting step; The direction adjustment step comprises the following steps: Acquire a maximum threshold and a minimum threshold according to the preset distance difference threshold range; Obtaining a camera number corresponding to a real-time image showing the reference line; Determining the relative position of the reference line and the vehicle body according to the relative position of the camera and the vehicle body; When the reference line is located on the left side of the vehicle body and the distance difference is greater than the maximum threshold, or when the reference line is located on the right side of the vehicle body and the distance difference is less than the minimum threshold, controlling the vehicle body to adjust its direction to the left; When the reference line is located on the right side of the vehicle body and the distance difference is greater than the maximum threshold, or when the reference line is located on the left side of the vehicle body and the distance difference is less than the minimum threshold, the vehicle body is controlled to adjust its direction to the right.

2. The robot linear motion control method according to claim 1, characterized in that: In the reference line identification step, After the step of calculating the distance between each candidate straight line and the origin, the following steps are also included: It is determined whether the distance between each candidate straight line and the origin is within a preset distance threshold range. If not, the candidate straight line is eliminated.

3. The robot linear motion control method according to claim 1, characterized in that: After the image acquisition step, the method further includes the following steps: Determine whether the brightness of the real-time image is less than a preset brightness threshold; if so, start the fill light device and return to the step of acquiring images on both sides of the vehicle body.

4. A data processing device, characterized in that: include A memory for storing executable program codes; as well as A processor is connected to the memory, and runs a computer program corresponding to the executable program code by reading the executable program code, so as to execute the robot straight-line motion control method according to any one of claims 1 to 3.

5. A robot, characterized in that: Comprising a data processing device as claimed in claim 4.

6. The robot according to claim 5, characterized in that: Also includes a vehicle body capable of traveling over the photovoltaic panel array; and Cameras are arranged on the left and right sides of the vehicle body; the lenses of the cameras face the photovoltaic panel array to collect images of the two sides of the vehicle body; The data processing device is arranged in the vehicle body and is connected to the camera.

7. The robot according to claim 5, characterized in that: Also includes A fill light device connected to the data processing device; When the brightness of the image collected by the camera is less than or equal to a preset brightness threshold, the fill light device is activated.

8. The robot according to claim 5, characterized in that: Also includes A gyroscope is connected to the data processing device, and is used to obtain the real-time moving direction of the vehicle body in real time.

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