Photovoltaic cleaning robot self-adaptive deviation correction method based on three-level feedback adjustment mechanism

Abstract

The invention belongs to the field of photovoltaic cleaning robots, and provides a photovoltaic cleaning robot self-adaptive correction method based on a three-level feedback adjustment mechanism in order to solve the problem of operation correction of a hanging rail type photovoltaic cleaning robot on a limited rail. Based on multi-data fusion of motor pulse, an operation attitude angle and a motor current characteristic value of the cleaning robot, a set of hierarchical feedback regulation system is established and comprises a speed loop, an angle loop and a current loop. Through the three independent closed-loop control systems, a hierarchical feedback mechanism is formed, and real-time monitoring and step-by-step reporting of the state of the robot are achieved. Therefore, mutual correction of the data sources in the operation process of the robot is completed, the inclination phenomenon of the robot during operation is accurately detected and corrected, and the cleaning efficiency of the photovoltaic cleaning robot is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic cleaning robots, and in particular to a photovoltaic cleaning robot self-adaptive deviation correction method based on a three-level feedback adjustment mechanism of a cleaning robot motor pulse, a running posture angle and a motor current characteristic value. Background Art

[0002] With the rapid advancement of solar energy technology, photovoltaic power plants have become one of the preferred renewable energy solutions in many regions around the world. However, the performance of photovoltaic systems is affected by a variety of external factors, the most notable of which is the dust, bird droppings and other pollutants covering the photovoltaic panels, which greatly reduce the photoelectric conversion efficiency of photovoltaic cells. Therefore, ensuring the cleanliness of the surface of photovoltaic panels is crucial to maintaining the efficient operation of the entire photovoltaic power generation system. In order to effectively meet this challenge, a series of cleaning robots designed specifically for photovoltaic panels have been introduced. Through automated cleaning methods, they not only improve cleaning efficiency, but also reduce the cost and risk of manual maintenance, becoming an indispensable technical means to improve the performance of photovoltaic power plants.

[0003] Figure 1 As shown in the figure, the rail-mounted photovoltaic cleaning robot is a common photovoltaic module cleaning device. The rail-mounted photovoltaic cleaning robot is a common device currently used to maintain the cleanliness of photovoltaic modules. This type of robot is designed to move along the long edges of both sides of the rectangular photovoltaic panel. Its structure includes a bar-shaped main body and two wheels installed at both ends of the main body. The two wheels are driven by the main motor and the driven motor respectively, so that the entire device can move smoothly on the photovoltaic panel. In addition, limit mechanisms are also equipped at both ends of the bar-shaped main body. These mechanisms are close to the side of the photovoltaic panel to ensure that the robot can move freely on the surface of the photovoltaic panel without slipping, and limit sensors are installed on the front and rear sides of the limit device to ensure that the robot can accurately drive into the parking position and stop. In order to ensure smooth operation, the distance between the limit mechanisms is slightly larger than the actual width of both sides of the photovoltaic panel. This ingenious design gives the rail-mounted photovoltaic cleaning robot a wide coverage area and efficient cleaning ability, making it widely used. However, in actual operation, due to the unevenness of the edges of the photovoltaic panel, the accumulation of external dirt, wind force or mechanical failure, the rail-mounted photovoltaic cleaning robot sometimes deviates from the track. Such deviation may not only lead to poor cleaning results, but in severe cases may even cause damage to the PV panels.

[0004] At present, in order to solve the problem of deviation correction of the rail-mounted photovoltaic cleaning robot on a limited track, the industry has carried out a variety of research, as shown in the table below. These include adding additional sensors, steering structures and other devices on the outside, using angle sensors, ultrasonic sensors and other sensors to collect data and perceive changes in the robot's posture.

[0005]

[0006] Patent [1] mainly uses data acquisition modules and steering mechanisms to monitor and correct the path deviation of the photovoltaic robot in real time. However, this research method does not take into account the displacement path deviation caused by the robot slipping, accidental jamming, etc. This deviation cannot truly reflect the robot's posture deviation.

[0007] Patent [2] mainly adopts follower arms, side wheels, swing detection elements and elastic reset parts to prevent the robot from getting stuck. However, this research method does not completely solve the problem of deflection. It only avoids the risk of the robot getting stuck during operation, and does not consider the cleaning efficiency and operating power of the robot in the case of deflection.

[0008] Patent [3] mainly obtains the robot's azimuth during operation by obtaining the acceleration value and angular velocity value during operation, and monitors and executes correction instructions in real time by comparing with the preset azimuth. However, this research method does not take into account that the value of the Z-axis angular acceleration of the robot during operation will have cumulative errors. As the running time increases, the accuracy of its azimuth decreases, and it cannot accurately reflect the robot's posture during operation. At the same time, it also does not propose how to calibrate the data.

[0009] Patent [4] mainly uses mechanical means to detect the tilt angle between the upper walking mechanism and the lower walking mechanism, and amplifies the tilt angle of the photovoltaic cleaning robot so that the encoder can quickly detect the tilt angle and correct it. However, this research method does not take into account the wear error of the machine and the interference factors of the external environment. As the use time increases, the tilt angle cannot accurately reflect whether the two ends of the robot are actually deflected.

[0010] Patent [5] uses an edge detection sensor installed on the cleaning roller brush bracket at the front end of the walking cleaning robot to identify the edge of the component frame on the power station bracket and determine whether the robot has deviated from the cleaning route due to the imbalance of the driving wheel or the tilt of the power station bracket causing the robot to slip sideways. This research method proposes installing an edge detection sensor, which requires manual regular cleaning of the exposed edge detection sensor, and does not consider the use of edge detection sensors in harsh environments.

[0011] Patent [6] mainly uses ultrasonic detectors to monitor the distance between the two guide wheels on the same side and the side of the photovoltaic panel, so as to determine whether the photovoltaic cleaning robot is tilted and the tilt direction. In actual environmental testing, ultrasonic detectors have special requirements for installation height and position. On this type of rail-mounted photovoltaic cleaning robot equipment, the distance between the guide wheel position and the photovoltaic panel surface is close to the effective distance detected by the ultrasonic detector. This research method does not take into account the blind spot problem caused by the ultrasonic detector being too close to the photovoltaic panel surface, as well as the gap error at the connection between the photovoltaic panels.

[0012] Patent [7] mainly analyzes the current change trend of the robot's main motor and slave motor in real time, compares the current difference between the main motor and the slave motor with the preset reference value, intelligently judges the motor's operating status, and detects the robot's posture. This research method uses current data to avoid the additional cost of external devices and the cumulative error caused by the external environment. However, during the research process, it was found that the method described in the patent mentioned the need for additional preset reference values, which greatly reduced the universality of the method. The motor current values ​​of the same machine in different environments and years of use vary to a certain extent. This requires the operator to conduct multiple tests on the robot in a fixed environment and quantity each time to obtain an accurate reference value. In addition, the motor current is affected by environmental factors such as photovoltaic brackets and weather, and there is a certain range of fluctuations. Therefore, the preset value is a real-time error correction, which lacks flexibility.

[0013] Combining the above-mentioned major research directions in the industry, in order to realize robot deflection detection and correction, the research method mainly uses external devices or sensors to collect additional data to perceive the robot's operating posture.

[0014] In the above-mentioned patent [3-4] research method, the angle sensor data used, after the on-site angle sensor use test, whether using a six-axis or nine-axis sensor, its yaw angle in the Z-axis direction is easily disturbed by the running vibration or magnetic field, and will produce cumulative errors in long-term operation. Therefore, it is necessary for the robot to have a clear fixed direction or data reflecting the accurate posture of the robot every time a period of time passes to correct the angle data error. In the patent [3-4] research method, it uses a single data source, and only the angle data can reflect the running posture of the robot, and it does not clearly propose how to solve or correct the cumulative error of the angle sensor. Therefore, when the data has errors, the data source cannot be calibrated, resulting in the data being unable to correctly reflect whether the two ends of the robot are actually deflected. In the research methods of patents [1-2] and [5-6], the external devices and other sensors used have the same situation as patent [3-4], that is, the single data source cannot perform timely data calibration when there are cumulative errors or wear errors in the data.

[0015] Patent [7] innovatively proposed that there is no need to install additional external devices and sensors, and only the internal motor current data of the robot can be used as the basis for robot operation deviation detection. Its core method is: collect and analyze the motor current change trend of the robot under different operation postures, compare the motor current value of the robot under normal operation without deviation, extract the characteristic value of the current data, and set the corresponding threshold value to achieve effective detection of the robot's deviation state. Therefore, according to patent [7], two different robots of the same model were tested under the same conditions and the same machine was tested in different venues and at different speeds. The collected motor current change curves were compared and analyzed, and it was found that there were obvious differences in the motor current operation trends in the tests under the above conditions. Obviously, as described in patent [7], the preset motor current reference value as the threshold for sensing the robot's running posture change cannot be applied to all operating conditions; in the field test, it was also found that when the robot runs through the metal bridge between the photovoltaic panels, the motor current will produce data fluctuations, which will cause the robot to misjudge the posture deviation. Similarly, the research method of patent [7] also only uses a single data source. Therefore, for the misjudgment problem caused by the fluctuation of motor current data due to the above-mentioned abnormal situation, it is also impossible to use other data that can reflect the accurate operating posture of the robot for auxiliary judgment, and the preset baseline value method it adopts cannot cover all operating conditions. Summary of the invention

[0016] Because of the above-mentioned deficiencies in the prior art, the present invention proposes an innovative solution: an adaptive deviation correction method for a photovoltaic cleaning robot based on a three-level feedback adjustment mechanism. The method aims to enhance the operating accuracy and stability of the robot in a changing environment, and has the characteristics of real-time response, high fault tolerance and self-adaptation, without the need for preset thresholds.

[0017] This method combines the pulse data, current characteristic values ​​and heading angle data of the master and slave motors to establish a hierarchical feedback regulation system, including speed loop, angle loop and current loop. Through these three independent closed-loop control systems, a hierarchical speed-angle-current three-level feedback regulation mechanism is formed, which realizes real-time monitoring and step-by-step reporting of the robot status. The core point is: combined with the above angle sensor angle data has cumulative errors and cannot be accurately corrected, the current data is due to the poor universality of the preset reference value and the misjudgment factors under abnormal conditions. This mechanism uses the previous angle data to complete the collection and recording of the motor current characteristic reference value under the condition of stability and accuracy, and the factors of environmental interference of the current value during operation can be perceived by the angle data, thereby eliminating the misjudgment situation; similarly, the cumulative error in the angle data after the running time increases can also be used at a fixed interval during the operation process. The trend change of the current characteristic value is used to support the change of the angle data. If there is an error, the yaw angle reference value can be updated immediately, so as to complete the mutual correction of the data source during the operation of the robot, so as to accurately detect and correct the tilt phenomenon of the robot operation, and ensure the cleaning efficiency of the photovoltaic cleaning robot.

[0018] Through the three-level feedback adjustment mechanism based on motor pulse, motor current and running attitude angle, there is no need to use additional mechanical devices or optimize the mechanical structure, and its six-axis sensor is also directly integrated on the main control board, so as to realize a low-cost, high-efficiency, high-fault-tolerant photovoltaic cleaning robot adaptive correction method based on the three-level feedback adjustment mechanism. This method collects and analyzes the motor pulse, motor current, and running attitude angle data, and uses the hierarchical feedback adjustment mechanism to monitor and judge the robot's operating status in real time, and promptly discover and correct the tilt problem, thereby ensuring the cleaning quality of the photovoltaic module and the safe operation of the photovoltaic cleaning robot. This method can not only ensure the accuracy of the robot's correction in an ideal environment, but also use the hierarchical feedback adjustment mechanism to mutually verify the accuracy of the data in special circumstances, and timely correct the data errors. It has high data reliability, greatly reduces additional human intervention, and improves the operation and maintenance efficiency of photovoltaic power stations.

[0019] The present invention relates to a photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism. Through the pulse data of the main motor and the slave motor, the motor current characteristic value data and the robot heading angle data, and the establishment of a hierarchical feedback adjustment mechanism, the method realizes the accurate detection and correction of the robot's posture during operation. First, in the operation preparation stage, the heading angle of the robot at the parking position is collected as the heading angle reference value to ensure the initial state of the attitude angle. Then, the running distance between the main motor and the slave motor is calculated using the number of pulses generated by the motor operation, and the closed-loop control of the incremental PID technology is adopted to ensure that the running speed of the slave motor can be detected and compensated in real time. At the same time, when the robot runs stably and meets the collection conditions, the motor current data is collected and the collected current data is preprocessed to improve the accuracy and stability of the data. On this basis, the motor current characteristic reference value is determined. Finally, an independent closed-loop control system is established through three data, namely the speed loop-angle loop-current loop system, and a current-angle-speed loop hierarchical feedback adjustment mechanism is established to monitor the robot's operating status in real time and provide feedback to higher levels until the highest-level feedback adjustment mechanism receives feedback data and performs data analysis and compensation to achieve real-time monitoring of the robot's operating status and effective deviation correction. This method has the characteristics of real-time, high fault tolerance and adaptability. It does not require manual setting of thresholds. Through the mutual verification of multiple data, real-time error correction and update of data are achieved. It is particularly suitable for scenes with complex environments such as photovoltaic power stations and high requirements for track operation accuracy, greatly improving the cleaning efficiency and operation stability of the robot.

[0020] The present invention provides a photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism.

[0021] The adaptive deviation correction method includes a three-level feedback adjustment mechanism, the first level is based on the current loop method, the second level is based on the angle loop method, and the third level is based on the speed loop method;

[0022] The speed loop method includes: real-time acquisition of the number of pulses generated by the operation of the main motor and the slave motor, judging whether deflection occurs based on the number of pulses, and if deflection occurs, triggering the speed loop to start the following adjustment mechanism: taking the main motor as a reference, using the incremental PID control method to compensate and adjust the running speed of the slave motor to achieve deviation correction;

[0023] The angle loop method includes: collecting the current heading angle in real time, judging whether deflection occurs based on the current heading angle and the heading angle reference value, and if deflection occurs, triggering the angle loop to start the following adjustment mechanism:

[0024] The current loop method comprises: collecting the current current characteristic value in real time, judging whether a deviation occurs based on the current current characteristic value and the current characteristic value reference value, and if a deviation occurs, triggering the current loop to start the following adjustment mechanism: executing the second-level feedback adjustment mechanism; the method comprises the following steps:

[0025] S1, if the heading angle of the robot at the parking position is within the preset range, the heading angle of the robot at the parking position is collected as the heading angle reference value, and the main motor and the slave motor are started to enter the first stage of operation;

[0026] S2, based on the actual working scenario of the robot, the area without photovoltaic panels within X meters of the parking position is defined as the parking position area. When the robot runs in the parking position area, the second-level feedback adjustment mechanism is executed to correct the deviation;

[0027] S3, when the robot runs more than X meters, it leaves the parking area and enters the second stage of operation. The second stage of operation is in the photovoltaic panel area. During the first T time of the second stage of operation, the robot's running speed has not yet accelerated to the set value, and the motor current data has not reached the peak value, so its motor current characteristic data cannot correctly represent the robot's running posture, so the second-level feedback adjustment mechanism is executed for correction;

[0028] S4, when the robot runs for a longer time than T in the second stage, while executing the second-level feedback adjustment mechanism to correct the deviation, it continuously collects the main motor current and the slave motor current data and converts them into motor current characteristic values;

[0029] S5, determining whether the angle loop is continuously triggered to start the adjustment mechanism within a preset time, and if not, taking the current motor current characteristic value as the motor current characteristic reference value;

[0030] S6, if yes, record the current motor current characteristic value, wait for a preset time and then repeat step S5, if still yes, record the current motor current characteristic value, wait for a preset time and then repeat step S5, repeat at most M times, take the average value of the M-times recorded current characteristic value as the motor current characteristic reference value;

[0031] S7, after obtaining the motor current characteristic reference value, the robot enters the third stage of operation. In this stage, the robot still operates in the photovoltaic panel area and executes the first-level feedback adjustment mechanism and the second-level feedback adjustment mechanism to jointly correct the deviation.

[0032] Preferably, the step S7 further includes the following steps:

[0033] S8, when the robot is in the third stage of operation, if neither the current loop start adjustment mechanism nor the angle loop start adjustment mechanism is triggered, that is, the robot has not deviated, in this case, the robot updates the current motor current characteristic value and heading angle to the motor current characteristic reference value and heading angle reference value every time it runs a preset distance;

[0034] S9, if the current loop start adjustment mechanism is not triggered, but the angle loop start adjustment mechanism is triggered: the misjudgment comes from the motor current data, and the motor current characteristic reference value is updated to the current motor current characteristic value;

[0035] S10, if the current loop is triggered to start the adjustment mechanism, but the angle loop is not triggered to start the adjustment mechanism: the misjudgment comes from the angle data, and the heading angle reference value is updated to the current heading angle;

[0036] At the same time, in the third stage of operation, S11 detects whether there is a limit sensor trigger. If not, repeat S8-10. If triggered, the robot reaches the end stop position, changes the running direction, and repeats S1-11.

[0037] Preferably, in S1, the preset range is 90°±3°.

[0038] Preferably, in S4, the conversion into motor current characteristic values ​​specifically includes preprocessing the current data including reducing noise, smoothing data, and processing abnormal values; and converting the preprocessed current data into motor current characteristic values ​​through a root mean square calculation formula.

[0039] Preferably, in S5 and S6, the preset time is 3 seconds.

[0040] Preferably, the output is a signal for triggering the speed loop to start the adjustment mechanism; specifically, it includes: outputting a fixed number of pulses to increase or decrease the number of pulses of the main motor, thereby triggering the speed loop to start the adjustment mechanism, performing slave motor speed compensation, and thus correcting the robot's running posture.

[0041] Preferably, in S8, the preset distance is recorded as Y, and the setting value interval of Y is [5, 10]; the setting value interval of M is [3, 5]; the setting value interval of X is [1, 1.2]; and the setting value interval of T is [10, 15] seconds.

[0042] Preferably, the rail-mounted photovoltaic cleaning robot is used for cleaning rectangular photovoltaic panels.

[0043] Preferably, the heading angle is the attitude angle in the Z-axis direction calculated by a six-axis sensor carried on the robot main control board.

[0044] Preferably, judging whether deflection occurs based on the number of pulses specifically includes:

[0045] Get the circumference of the driving wheel and the driven wheel respectively;

[0046] The distance traveled by one end of the fuselage where the driving wheel is located is calculated by multiplying the circumference of the driving wheel by the number of pulses of one revolution of the main motor;

[0047] The distance traveled by one end of the fuselage where the driven wheel is located is calculated by multiplying the circumference of the driven wheel by the number of pulses in one revolution of the slave motor;

[0048] Whether or not a deviation occurs is determined based on the difference in the above distances.

[0049] The rail-mounted photovoltaic cleaning robot is used for cleaning rectangular photovoltaic panels;

[0050] The hanging rail is the edge of the long sides of the rectangular photovoltaic panel. The hanging rail type photovoltaic cleaning robot includes a strip-shaped fuselage, and a driving wheel and a driven wheel are respectively arranged at both ends of the fuselage; the driving wheel and the driven wheel are respectively driven by the main motor and the slave motor; limiting structures are also arranged at both ends of the fuselage, and the limiting structures at both ends of the fuselage are clamped on the edges of the long sides of the rectangular photovoltaic panel, so that the photovoltaic cleaning robot can move on the photovoltaic panel without falling from the photovoltaic panel; the distance between the limiting structures at both ends of the fuselage is greater than the distance between the long sides of the rectangular photovoltaic panel.

[0051] The parking area and the photovoltaic panel area are a bracket photovoltaic panel group composed of rectangular photovoltaic panels used in the rail-mounted photovoltaic robot, with the two ends of the bracket being the parking area and the middle being the photovoltaic panel area.

[0052] Preferably, the angle formed by the robot in the stationary state before departure from the parking position and the side bracket of the parking position is 90°, with an acceptable error range of ±3°, and according to quantitative tests, the robot's posture will not deviate within 20 seconds from the acceleration to stability after the robot leaves the parking position in the absence of external abnormalities.

[0053] Specifically, when a robot fails or stops running manually, the robot will enter the fault state or standby state accordingly. In this state, the robot will enter different loop feedback mechanism states according to its position and corresponding recovery conditions for operation. For details, see Figure 2 .

[0054] The beneficial effects of the present invention are as follows: 1) Real-time state detection of the movement of the rail-mounted photovoltaic cleaning robot is realized, and data accuracy is mutually verified by establishing and utilizing a hierarchical feedback adjustment mechanism, and data error correction is performed in a timely manner, and the robot's movement posture is compensated in real time to ensure that the robot can maintain a normal posture for cleaning operation. 2) Closed-loop control using incremental PID technology ensures real-time detection and compensation of the motor operating speed. 3) No additional devices are required, and correction processing is performed through multi-data fusion adaptive scenarios. 4) Closed-loop control system, establishes an independent closed-loop control system, namely a speed loop-angle loop-current loop system, to ensure the data stability of the robot under various operating conditions and improve the operating efficiency and reliability of the overall system. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a structural diagram of the rail-mounted cleaning robot of the present invention;

[0056] Figure 2 It is a curve diagram of the heading angle data change when the robot of the present invention is started at the parking position in three different postures;

[0057] Figure 3 It is a filter current variation curve diagram of the main motor at 200 window points when the robot of the present invention is started at three different postures at the parking position;

[0058] Figure 4 It is a curve diagram of filter current variation from the motor at 200 window points when the robot of the present invention is started at three different postures at the parking position;

[0059] Figure 5 It is a curve diagram showing the change of the RMS value of the main motor current when the robot of the present invention is started at the parking position in three different postures;

[0060] Figure 6 It is a curve diagram of the change of the RMS value of the motor current when the robot of the present invention is started in three different postures at the parking position. DETAILED DESCRIPTION

[0061] 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 a part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application. In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar promotions without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0062] In this embodiment, the rail-mounted photovoltaic cleaning robot is referred to as a robot. In this embodiment, when the robot is not in a fault or manual shutdown state, it only stops and waits at the parking positions at both ends. Specifically, in this embodiment, the parking position at the starting end of the robot is called the initial parking position, hereinafter referred to as the parking position; in addition, the parking position at the arrival end of the robot is called the limit position. When the robot stops at the parking position or the limit position, it means that the cleaning task has been completed or the cleaning task is waiting to be started.

[0063] In this embodiment, the adaptive deviation correction method includes a three-level feedback adjustment mechanism, the first level is based on a current loop method, the second level is based on an angle loop method, and the third level is based on a speed loop method.

[0064] In this embodiment, the speed loop method includes: real-time collection of the number of pulses generated by the operation of the main motor and the slave motor, judging whether a deviation occurs based on the number of pulses, and if a deviation occurs, triggering the speed loop to start the following adjustment mechanism: taking the main motor as a reference, using an incremental PID control method to compensate and adjust the running speed of the slave motor to achieve deviation correction.

[0065] In this embodiment, the angle loop method includes: real-time acquisition of the current heading angle, judging whether deflection occurs based on the current heading angle and the heading angle reference value, and if deflection occurs, triggering the angle loop to start the following adjustment mechanism.

[0066] In this embodiment, the current loop method includes: real-time acquisition of the current characteristic value, judging whether a deviation occurs based on the current characteristic value and the current characteristic value reference value, and if a deviation occurs, triggering the current loop to start the following regulation mechanism: executing the second-level feedback regulation mechanism.

[0067] The robot is in the operation preparation stage, specifically, Figure 2As shown, the robot is within 200 sampling intervals, that is, within 20s. Obviously, within 20s, no matter it is started and operated in the parking position with three initial postures: no deviation, main motor deviation, and slave motor deviation, the change of its heading angle will not exceed 2°. At the same time, after testing in this embodiment, the distance traveled by the robot running at the minimum speed required by the safety regulations for 20s is fully able to meet the robot entering the second stage of operation. Therefore, when the heading angle of the robot is in the parking position, it is within the preset range, that is, the angle formed by the robot in the static state before the departure of the parking position and the side bracket of the parking position is 90±3°, then the heading angle of the current position of the robot is collected, and the current heading angle is used as the heading angle reference value. Specifically, in this embodiment, based on the actual working scene of the robot, the area without photovoltaic panels within X meters of the parking position is defined as the parking position area. When the robot runs in the parking position area, the second-level feedback adjustment mechanism is executed to correct the deviation.

[0068] In this embodiment, when the robot's running distance is greater than X meters, it leaves the parking area and enters the second stage of operation. The second stage of operation is in the photovoltaic panel area. During the first T time of the second stage of operation, the robot's running speed has not yet accelerated to the set value, and the motor current data has not reached the peak-to-peak value. Therefore, its motor current characteristic data cannot correctly represent the robot's running posture, so the second-level feedback adjustment mechanism is executed to correct the deviation.

[0069] In this embodiment, when the robot is running for more than T in the second stage, while executing the second-level feedback adjustment mechanism for correction, the main motor current and the slave motor current data are continuously collected and converted into motor current characteristic values. Specifically, when the robot is running for more than T in the second stage, the current data of the main motor and the slave motor will be continuously collected, and the sliding window mean filtering will be performed, and the window sampling points are 200. The current data of the main motor and the slave motor are removed for abnormal values ​​to reduce the interference of noise and instantaneous values, and the pre-processed current data is converted into motor current characteristic values ​​through the root mean square calculation formula. At the same time, it is determined whether the current overall state of the robot meets the recording conditions of the motor current characteristic reference value, that is, it is determined whether the angle ring is continuously triggered to start the adjustment mechanism within the preset time of 3s. Obviously, if yes, record the current motor current characteristic value, wait for the preset time and repeat step S5, if still yes, record the current motor current characteristic value, wait for the preset time of 3s and repeat step S5, repeat M times at most, and take the average value of the current characteristic value recorded M times as the motor current characteristic reference value.

[0070] like Figure 3 , Figure 4 , Figure 5 , Figure 6As shown in the figure, after testing, the selection of the root mean square value of the current characteristic value of the robot's main motor and slave motor can more accurately and clearly express the operation status of the robot in different postures than directly using the motor current value. Specifically, when the motor current is used to judge the different postures of the robot's operation, the current data is difficult to intuitively reflect its trend characteristics. Obviously, when the motor current root mean square value is used, it can intuitively reflect the trend characteristics of different operating postures, and it is easier to judge whether the robot is in a skewed state, and it can accurately judge whether it is in the main motor skew or the slave motor skew. In comparison, Figure 5 , Figure 6 High accuracy and low error rate.

[0071] In this embodiment, the number of windows where the motor current root mean square is selected as the motor current characteristic value is 150. Specifically, the collected motor current characteristic reference value directly reflects the motor current characteristic reference value of the robot when it is running without deviation, without the need to manually set the threshold in advance. Next, compare whether the current characteristic values ​​of the main motor and the slave motor of the current robot are abnormal to the current characteristic reference value, and input the comparison result as the input into the current loop control system, setting its independent loop system as the first-level feedback regulation mechanism.

[0072] In this embodiment, after completing the collection of the motor current characteristic baseline value, the robot enters the third stage of operation. In this stage, the robot still operates in the photovoltaic panel area, and simultaneously executes the first-level feedback adjustment mechanism and the second-level feedback adjustment mechanism to jointly correct the deviation. Specifically, in combination with the above, the first judgment point is changed from the second-level feedback adjustment mechanism to the first-level feedback adjustment mechanism.

[0073] In this embodiment, when the first-level feedback adjustment mechanism is executed, if the current loop starts the adjustment mechanism, that is, the motor current characteristic value is different from the reference value. At this time, it is detected whether the angle loop starts the adjustment mechanism. If it is not triggered, it is considered that the robot has bumps, vibrations, and other interferences in the running posture during operation. At this time, if the robot is running stably and the angle loop adjustment mechanism is not continuously triggered, the current motor current characteristic data is updated to the new motor current characteristic reference value; if the angle loop adjustment mechanism is triggered, it is considered that the robot is deflected, and the incremental PID control method is used to compensate and adjust the running speed of the slave motor based on the main motor to achieve deviation correction.

[0074] Similarly, in this embodiment, when the current loop adjustment mechanism is not triggered and the angle loop adjustment mechanism is triggered, it is considered that the robot has accumulated errors in the heading angle data during operation and needs to clear the accumulated errors. At this time, when the robot is running stably and the adjustment mechanism is not triggered, the current heading angle data is updated to the new heading angle reference value. During the third stage of operation, when both the current loop adjustment mechanism and the angle loop adjustment mechanism are not triggered, it is determined that the robot is not deflected. In this case, the robot updates the current motor current characteristic data to the new motor current characteristic reference value and the current heading angle data to the new heading angle reference value every Y meters it runs.

[0075] In this embodiment, considering the situation that the robot has a fault or is stopped midway by human operation and enters a fault or standby state, when restarting in this case, the historical log will be called out first to trace the last running distance. Specifically, the position of the robot is determined, and different hierarchical adjustment mechanisms will be used to operate according to different positions to ensure cleaning efficiency and correction accuracy. Obviously, after the robot runs away from the initial parking position, the limit sensor detection is turned on. When the limit sensor is triggered, the robot reaches the terminal parking position. At this time, the robot turns the running direction and repeats the above steps to continue the cleaning task. The photovoltaic cleaning robot adaptive correction method based on the three-level feedback adjustment mechanism proposed by the present invention can realize real-time monitoring and effective correction of the robot's running state. This method has the characteristics of real-time, high fault tolerance and adaptability. It does not require artificial setting of thresholds. Through the mutual correction of multiple data, real-time error correction and update of data are realized. It is particularly suitable for scenes with complex environments such as photovoltaic power stations and high requirements for track operation accuracy, which greatly improves the cleaning efficiency and operation stability of the robot.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism, characterized in that: The adaptive deviation correction method includes a three-level feedback adjustment mechanism, the first level is based on the current loop method, the second level is based on the angle loop method, and the third level is based on the speed loop method; The speed loop method includes: real-time acquisition of the number of pulses generated by the operation of the main motor and the slave motor, judging whether deflection occurs based on the number of pulses, and if deflection occurs, triggering the speed loop to start the following adjustment mechanism: taking the main motor as a reference, using the incremental PID control method to compensate and adjust the running speed of the slave motor to achieve deviation correction; The angle loop method includes: collecting the current heading angle in real time, judging whether deflection occurs based on the current heading angle and the heading angle reference value, and if deflection occurs, triggering the angle loop to start the following adjustment mechanism: The current loop method comprises: collecting the current current characteristic value in real time, judging whether a deflection occurs based on the current current characteristic value and the current characteristic value reference value, and if a deflection occurs, triggering the current loop to start the following regulation mechanism: executing the second-level feedback regulation mechanism; The following steps are involved: S1, if the heading angle of the robot at the parking position is within the preset range, the heading angle of the robot at the parking position is collected as the heading angle reference value, and the main motor and the slave motor are started to enter the first stage of operation; S2, based on the actual working scenario of the robot, the area without photovoltaic panels within X meters of the parking position is defined as the parking position area. When the robot runs in the parking position area, the second-level feedback adjustment mechanism is executed to correct the deviation; S3, when the robot runs a distance greater than X meters, the second-level feedback adjustment mechanism is executed to correct the deviation within the first T time of the second stage operation; S4, when the robot runs for a longer time than T in the second stage, while executing the second-level feedback adjustment mechanism to correct the deviation, it continuously collects the main motor current and the slave motor current data and converts them into motor current characteristic values; S5, determining whether the angle loop is continuously triggered to start the adjustment mechanism within a preset time, and if not, taking the current motor current characteristic value as the motor current characteristic reference value; S6, if yes, record the current motor current characteristic value, wait for a preset time and then repeat step S5, if still yes, record the current motor current characteristic value, wait for a preset time and then repeat step S5, repeat at most M times, take the average value of the M-times recorded current characteristic value as the motor current characteristic reference value; S7, after obtaining the motor current characteristic reference value, executing the first-level feedback regulation mechanism and the second-level feedback regulation mechanism to jointly perform deviation correction.

2. The photovoltaic cleaning robot adaptive deviation correction method based on the three-level feedback adjustment mechanism according to claim 1 is characterized in that: The step S7 further includes the following steps: S8, when the robot is in the third stage of operation, if neither the current loop start adjustment mechanism nor the angle loop start adjustment mechanism is triggered, the robot updates the current motor current characteristic value and heading angle to the motor current characteristic reference value and heading angle reference value every time it runs a preset distance; S9, if the current loop start adjustment mechanism is not triggered, but the angle loop start adjustment mechanism is triggered: the motor current characteristic reference value is updated to the current motor current characteristic value; S10, if the current loop is triggered to start the adjustment mechanism, but the angle loop is not triggered to start the adjustment mechanism: the heading angle reference value is updated to the current heading angle; At the same time, in the third stage of operation, S11 detects whether there is a limit sensor trigger. If not, repeat S8-10. If triggered, the robot reaches the end stop position, changes the running direction, and repeats S1-11.

3. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 1, characterized in that: In S1, the preset range is 90°±3°.

4. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 1, characterized in that: In S4, the conversion into motor current characteristic values ​​specifically includes preprocessing the current data including reducing noise, smoothing data, and processing abnormal values; and converting the preprocessed current data into motor current characteristic values ​​through a root mean square calculation formula.

5. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 1, characterized in that: In S5 and S6, the preset time is 3 seconds.

6. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 1, characterized in that: The output is a signal for triggering the speed loop to start the adjustment mechanism; specifically, it includes: outputting a fixed number of pulses to increase or decrease the number of pulses of the main motor, thereby triggering the speed loop to start the adjustment mechanism, performing slave motor speed compensation, and thus correcting the robot's running posture.

7. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 2, characterized in that: In S8, the preset distance is recorded as Y, and the setting value interval of Y is [5, 10]; the setting value interval of M is [3, 5]; the setting value interval of X is [1, 1.2]; and the setting value interval of T is [10, 15] seconds.

8. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 2, characterized in that: The rail-mounted photovoltaic cleaning robot is used for cleaning rectangular photovoltaic panels.

9. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 2, characterized in that: The heading angle is the attitude angle in the Z-axis direction calculated by the six-axis sensor carried on the robot main control board.

10. The photovoltaic cleaning robot adaptive deviation correction method based on a three-level feedback adjustment mechanism as claimed in claim 2, characterized in that: The step of judging whether deflection occurs based on the number of pulses specifically includes: Get the circumference of the driving wheel and the driven wheel respectively; The distance traveled by one end of the fuselage where the driving wheel is located is calculated by multiplying the circumference of the driving wheel by the number of pulses of one revolution of the main motor; The distance traveled by one end of the fuselage where the driven wheel is located is calculated by multiplying the circumference of the driven wheel by the number of pulses in one revolution of the slave motor; Whether or not a deviation occurs is determined based on the difference in the above distances.

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