Anti-falling system and method for a photovoltaic panel cleaning robot

Abstract

The present invention discloses an anti-falling system and method for a photovoltaic panel cleaning robot, belonging to the technical field of photovoltaic cleaning. The system includes: a sensing and monitoring module, which is used to collect distance signals through a ranging sensor arranged on the photovoltaic panel cleaning robot; a hysteresis comparison module, which is used to perform hysteresis comparison on the distance signals according to the upper threshold of the distance signal and the lower threshold of the distance signal, define a hysteresis region, and generate an edge state signal of the ranging sensor; an anti-falling module, which is used to control the photovoltaic panel cleaning robot to perform an edge detection anti-falling task based on the edge state signal of the ranging sensor according to the anti-falling method. The present invention solves the problem that the photovoltaic panel cleaning robot is prone to fall at the edge of the photovoltaic panel.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic cleaning, and particularly relates to an anti-falling system and method for a photovoltaic panel cleaning robot. Background Art

[0002] As a clean and renewable energy source, solar energy has gradually become an important part of the global energy structure optimization due to its rich resources and good environmental benefits. Therefore, photovoltaic power generation technology has been widely used, especially occupying an important position in renewable energy power generation systems. The efficiency of photovoltaic power generation is often affected by many factors, and the accumulation of dirt on the surface of photovoltaic panels is one of the main factors. At present, large-scale photovoltaic power stations are generally deployed in arid and less rainy areas, and a large amount of dust in the air will accumulate on the surface of photovoltaic modules over time, thus significantly affecting the energy conversion of photovoltaic power stations, and further affecting the power generation efficiency and economic benefits of the entire photovoltaic system. For the cleaning of large photovoltaic modules, manual cleaning is mainly used. The method of manually cleaning photovoltaic panels not only has low efficiency and high cost, but may also cause irreversible damage to the surface of photovoltaic panels if the operation is improper.

[0003] Using a photovoltaic panel cleaning robot for cleaning can improve the cleaning efficiency. With the vigorous development of the photovoltaic cleaning industry, photovoltaic panel cleaning robots are usually equipped with precise sensors, actuators and electronic components, and these components are extremely vulnerable to damage when dropped. In order to ensure the stability and cleaning efficiency of photovoltaic panel cleaning robots, more and more portable photovoltaic panel cleaning robots have begun to try different adsorption technologies to ensure that they can firmly adhere to the smooth surface of photovoltaic panels and efficiently complete the cleaning tasks. However, the existing anti-falling technologies for cleaning robots are still difficult to avoid the risk of the robot falling during operation in special areas such as the edge of the working area, and cannot fully guarantee the cleaning effect of the edge position of the photovoltaic panel. Summary of the Invention

[0004] Aiming at the above deficiencies in the prior art, an anti-falling system and method for a photovoltaic panel cleaning robot provided by the present invention solves the problem that the photovoltaic panel cleaning robot is prone to falling at the edge of the photovoltaic panel.

[0005] In order to achieve the above invention purpose, the technical solution adopted by the present invention is as follows:

[0006] On the one hand, an anti-falling system for a photovoltaic panel cleaning robot provided by the present invention includes a sensing and monitoring module for collecting distance signals through a ranging sensor arranged on the photovoltaic panel cleaning robot;

[0007] A hysteresis comparison module for performing hysteresis comparison on the distance signal according to the upper threshold and lower threshold of the distance signal, defining a hysteresis region, and generating an edge state signal of the ranging sensor;

[0008] The anti - falling module is used to control the photovoltaic panel cleaning robot to perform edge detection and anti - falling tasks based on the edge state signal of the ranging sensor according to the anti - falling method.

[0009] Further, the ranging sensors on the photovoltaic panel cleaning robot include a left - front sensor, a right - front sensor, a left - rear sensor, a right - rear sensor, a front sensor, and a rear sensor.

[0010] Further, the hysteresis comparison module includes:

[0011] A threshold definition sub - module for defining the upper threshold of the distance signal and the lower threshold of the distance signal;

[0012] An edge judgment sub - module for comparing the size relationship between the distance signal and the upper threshold of the distance signal and the lower threshold of the distance signal to obtain the edge detection result of the ranging sensor. Among them, if the distance signal is greater than the upper threshold of the distance signal, the edge detection result is that an effective edge is detected; if the distance signal is less than the lower threshold of the distance signal, the edge detection result is that no edge is detected; if the distance signal is less than the upper threshold of the distance signal and greater than the lower threshold of the distance signal at the same time, the edge detection result is edge detection noise fluctuation.

[0013] In this solution, the distance signal does not represent the distance value. A large distance signal represents a short distance, that is, a large intensity of the reflected signal from the photovoltaic panel, and a small distance signal represents a long distance, that is, a small intensity of the reflected signal from the photovoltaic panel. For example, an infrared ranging sensor is used.

[0014] In this solution, the distance from the front sensor to the line connecting the left - front sensor and the right - front sensor is greater than the gap of the solar photovoltaic panel, and the distance from the rear sensor to the line connecting the left - rear sensor and the right - rear sensor is greater than the gap of the solar photovoltaic panel.

[0015] A hysteresis region sub - module for defining the hysteresis region for quantifying edge detection noise fluctuation;

[0016] An edge detection sub - module for generating the edge state signal of the distance sensor based on the edge detection result and the hysteresis region, where the edge state signal corresponds to the state inside the solar photovoltaic panel or the state outside the solar photovoltaic panel.

[0017] Further, the anti - falling module includes:

[0018] A task start sub - module for starting the photovoltaic panel cleaning robot and making the photovoltaic panel cleaning robot detect and find the edge of the photovoltaic panel;

[0019] An instruction definition sub - module for defining the action instructions of the photovoltaic panel cleaning robot, where the action instructions include a forward instruction, a backward instruction, a left - turn instruction, and a right - turn instruction;

[0020] An instruction generation sub-module, configured to generate corresponding action instructions for the photovoltaic panel cleaning robot according to the edge status signal of the ranging sensor;

[0021] An instruction execution sub-module, configured to control the motor movement of the photovoltaic panel cleaning robot according to the action instructions of the photovoltaic panel cleaning robot, so that the photovoltaic panel cleaning robot performs a forward action, a backward action, a left turn action or a right turn action;

[0022] An anti-falling sub-module, configured to control the photovoltaic panel cleaning robot to perform an edge detection and falling prevention task when detecting and searching for the edge of the photovoltaic panel based on the anti-falling method and the edge status signal of the ranging sensor.

[0023] On the other hand, based on the anti-falling system of the above-mentioned photovoltaic panel cleaning robot, the present invention correspondingly provides an anti-falling method for performing an edge detection and falling prevention task based on the anti-falling system of the above-mentioned photovoltaic panel cleaning robot; the anti-falling method includes the following steps:

[0024] A1. Obtain the edge status signal of the ranging sensor;

[0025] A2. Determine whether the backward condition is satisfied according to the edge status signal of the ranging sensor. If so, generate a backward instruction and transmit it to the message queue, and enter A7; otherwise, enter A3;

[0026] A3. Determine whether the forward condition is satisfied according to the edge status signal of the ranging sensor. If so, generate a forward instruction and transmit it to the message queue, and enter A7; otherwise, enter A4;

[0027] A4. Determine whether the condition for advancing across a seam is satisfied according to the edge status signal of the ranging sensor. If so, generate a forward instruction and transmit it to the message queue, and enter A7; otherwise, enter A5;

[0028] A5. Determine whether the right turn condition is satisfied according to the edge status signal of the ranging sensor. If so, generate a right turn instruction and transmit it to the message queue, and enter A7; otherwise, enter A6;

[0029] A6. Determine whether the left turn condition is satisfied according to the edge status signal of the ranging sensor. If so, generate a left turn instruction and transmit it to the message queue, and enter A7; otherwise, enter A8;

[0030] A7. Control the motor movement of the photovoltaic panel cleaning robot according to the action instructions in the message queue, so that the photovoltaic panel cleaning robot performs the corresponding action;

[0031] A8. Repeat A1-A7 until the photovoltaic panel cleaning robot completes the execution of the planned complete cleaning path, and then completes the execution of the edge detection and anti-falling task.

[0032] Further, the backward condition is that the edge state signals of the front sensor, the left front sensor, and the right front sensor all correspond to the state outside the solar photovoltaic panel;

[0033] The forward condition is that the edge state signals of the front sensor, the left front sensor, and the right front sensor all correspond to the state inside the solar photovoltaic panel, or the edge state signals of the left front sensor, the right front sensor, the left rear sensor, and the right rear sensor all correspond to the state inside the solar photovoltaic panel;

[0034] The condition for advancing across the seam is that while the edge state signals of the left front sensor and the right front sensor both correspond to the state outside the solar photovoltaic panel, the edge state signal of the front sensor corresponds to the state inside the solar photovoltaic panel;

[0035] The right turn condition is that the edge state signals of the left front sensor and the left rear sensor both correspond to the state outside the solar photovoltaic panel, or the edge state signal of the left front sensor corresponds to the state inside the solar photovoltaic panel and the edge state of the right rear sensor corresponds to the state outside the solar photovoltaic panel;

[0036] The left turn condition is that the edge state signals of the right front sensor and the right rear sensor both correspond to the state outside the solar photovoltaic panel, or the edge state signal of the right front sensor corresponds to the state inside the solar photovoltaic panel and the edge state of the left rear sensor corresponds to the state outside the solar photovoltaic panel.

[0037] The beneficial effects of the present invention are as follows: The anti-falling system of a photovoltaic panel cleaning robot provided by the present invention collects distance signals in real time through a sensing and monitoring module, and combines a hysteresis comparison module to accurately analyze the distance signals under the allowable gap noise error of the photovoltaic panel. The anti-falling module can quickly respond to commands, effectively control the photovoltaic panel cleaning robot to perform anti-falling tasks, significantly improve the safety of the robot during operation, and avoid falling accidents caused by inaccurate distance judgment or slow reaction; in the present invention, the hysteresis comparison module effectively reduces misjudgment caused by signal fluctuations or noise interference by setting the upper threshold and lower threshold of the distance signal and defining the hysteresis region, enhances the stable judgment ability of the system to distance changes, and enables the photovoltaic panel cleaning robot to maintain a stable operation state in a complex environment; through the precise ranging and anti-falling methods of the present invention, the photovoltaic panel cleaning robot can complete the cleaning task more efficiently. When encountering an edge or a possible falling situation, the photovoltaic panel cleaning robot can quickly make a judgment and take corresponding measures, avoiding unnecessary pauses or repeated actions, thereby improving the overall operation efficiency; the present invention combines sensing and monitoring, hysteresis comparison, and anti-falling control to achieve intelligent operation of the photovoltaic panel cleaning robot. Through the collaborative work of algorithms and sensors, the photovoltaic robot can autonomously sense the surrounding environment and make intelligent decisions according to the actual situation, improving the autonomous operation ability and intelligent level of the robot.

[0038] Other advantages of the present invention will be analyzed in more detail in the subsequent embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can be obtained based on these drawings.

[0040] Figure 1 It is a block diagram of an anti-falling system of a photovoltaic panel cleaning robot in an embodiment of the present invention.

[0041] Figure 2 It is a schematic diagram of a ranging sensor on a photovoltaic panel cleaning robot in an embodiment of the present invention.

[0042] Among them: 1. Front sensor; 2. Right front sensor; 3. Left front sensor; 4. Right rear sensor; 5. Rear sensor; 6. Left rear sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but only represents the selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0044] As Figure 1 shown, in an embodiment of the present invention, the present invention provides an anti-falling system for a photovoltaic panel cleaning robot, including:

[0045] A sensing and monitoring module, configured to collect distance signals through a distance sensor disposed on the photovoltaic panel cleaning robot; in this solution, the distance signal is the signal corresponding to the distance measured by the distance sensor on the photovoltaic panel cleaning robot along a fixed direction towards the photovoltaic panel side.

[0046] As Figure 2 shown, the distance sensors on the photovoltaic panel cleaning robot include a left front sensor 3, a right front sensor 2, a left rear sensor 6, a right rear sensor 4, a front sensor 1, and a rear sensor 5; the distance from the front sensor 1 to the line connecting the left front sensor 3 and the right front sensor 2 is greater than the gap of the solar photovoltaic panel, and the distance from the rear sensor 5 to the line connecting the left rear sensor 6 and the right rear sensor 4 is greater than the gap of the solar photovoltaic panel.

[0047] In this solution, the distance sensors are disposed at the four top corners of the photovoltaic panel cleaning robot, at the center position of the brush head of the photovoltaic panel cleaning robot, and at the protruding position of the center of the tail opposite to the center position of the brush head, that is, the distance sensors are respectively the left front sensor 3, the right front sensor 2, the left rear sensor 6, the right rear sensor 4, the front sensor 1, and the rear sensor 5.

[0048] The distance from the front sensor 1 to the line connecting the left front sensor 3 and the right front sensor 2 is greater than the gap of the solar photovoltaic panel. The distance from the rear sensor 5 to the line connecting the left rear sensor 6 and the right rear sensor 4 is greater than the gap of the solar photovoltaic panel.

[0049] A hysteresis comparison module, configured to perform hysteresis comparison on the distance signal according to the upper threshold and the lower threshold of the distance signal, define a hysteresis region, and generate an edge state signal of the distance sensor;

[0050] Since the gaps between photovoltaic modules may cause fluctuations in the ranging values measured by the ranging sensor, it is difficult to ensure the stable operation of the photovoltaic panel cleaning robot only relying on the distance signals provided by the ranging sensor. In this solution, in edge detection, through the hysteresis comparison module, the robustness to noise and environmental changes is enhanced, ensuring that the photovoltaic panel cleaning robot can effectively handle the cross-gap scenario and accurately execute path planning.

[0051] The hysteresis comparison module includes:

[0052] A threshold definition sub-module for defining the upper threshold of the distance signal and the lower threshold of the distance signal;

[0053] The calculation expressions for the upper threshold of the distance signal and the lower threshold of the distance signal are as follows:

[0054] , ,

[0055] where, represents the upper threshold of the distance signal, represents the mean value of the distance signal, represents the upper threshold sensitivity factor, represents the standard deviation of the distance signal, represents the lower threshold of the distance signal, represents the lower threshold sensitivity factor, where, ;

[0056] An edge judgment sub-module for comparing the size relationship between the distance signal and the upper threshold of the distance signal and the lower threshold of the distance signal to obtain the edge detection result of the ranging sensor. Among them, if the distance signal is greater than the upper threshold of the distance signal, the edge detection result is that no valid edge is detected; if the distance signal is less than the lower threshold of the distance signal, the edge detection result is that an edge is detected; if the distance signal is less than the upper threshold of the distance signal and at the same time greater than the lower threshold of the distance signal, the edge detection result is edge detection noise fluctuation;

[0057] In this solution, when the intensity of the distance signal of the sensor exceeds the upper threshold of the distance signal, it is determined that no valid edge or gap is detected; when the distance signal of the sensor is lower than the lower threshold of the distance signal, it is considered that the current edge or gap exists. When the signal is between these two thresholds, the action of the photovoltaic panel cleaning robot is kept in the previous state unchanged, thus avoiding unnecessary actions caused by short-term fluctuations in the sensor measurement value. Through the dual-threshold mechanism, this solution can help the action of the photovoltaic panel cleaning robot maintain stability when the distance signal changes insignificantly and reduce false triggering phenomena.

[0058] A hysteresis region sub-module for defining a hysteresis region for quantifying edge detection noise fluctuation;

[0059] The calculation expression of the hysteresis region is as follows:

[0060] ,

[0061] ,

[0062] wherein, represents the hysteresis region, represents the initial hysteresis width, represents the distance signal at time t, represents belonging to, represents the adjustment factor for the fluctuation of the distance signal, represents taking the absolute value, represents not belonging to, represents the instantaneous error of the distance signal, represents the average value of the ranging signal;

[0063] By setting an appropriate hysteresis region through the hysteresis region sub-module to achieve hysteresis control, it can effectively filter out instantaneous changes and ensure the smooth movement of the photovoltaic panel cleaning robot when crossing gaps.

[0064] The edge detection sub-module is used to generate the edge state signal of the distance sensor based on the edge detection result and the hysteresis region, wherein the edge state signal corresponds to the state inside the solar photovoltaic panel or the state outside the solar photovoltaic panel.

[0065] The calculation expression of the edge state signal is as follows:

[0066] ,

[0067] wherein, represents the edge state signal, represents the allowable error range, wherein when the edge state signal corresponds to the state where the photovoltaic panel cleaning robot is inside the solar photovoltaic panel, and when the edge detection signal corresponds to the state where the photovoltaic panel cleaning robot is outside the solar photovoltaic panel.

[0068] The anti-falling module is used to control the photovoltaic panel cleaning robot to perform the edge detection anti-falling task based on the edge state signal of the ranging sensor according to the anti-falling method.

[0069] The anti-falling module includes:

[0070] The task startup sub-module is used to start the photovoltaic panel cleaning robot and make the photovoltaic panel cleaning robot detect and find the edge of the photovoltaic panel;

[0071] The instruction definition sub-module is used to define the action instructions of the photovoltaic panel cleaning robot. Among them, the action instructions include forward instruction, backward instruction, left turn instruction, and right turn instruction;

[0072] The instruction generation sub-module is used to generate corresponding action instructions of the photovoltaic panel cleaning robot according to the edge state signal of the ranging sensor;

[0073] The instruction execution sub-module is used to control the motor movement of the photovoltaic panel cleaning robot according to the action instructions of the photovoltaic panel cleaning robot, so that the photovoltaic panel cleaning robot performs forward action, backward action, left turn action, or right turn action;

[0074] In the initial cleaning task stage, since the position of the photovoltaic panel cleaning robot is not always in the center of the photovoltaic panel, when the robot rotates to find the edge of the photovoltaic panel, it may approach or exceed the edge of the photovoltaic panel, posing a risk of falling. Falling will not only damage the photovoltaic panel cleaning robot, but also may damage the photovoltaic panel and affect its normal use. Therefore, this solution sets up an anti-falling sub-module to prevent the photovoltaic panel cleaning robot from falling from the photovoltaic panel when detecting and finding the edge of the photovoltaic panel.

[0075] The anti-falling sub-module is used to control the photovoltaic panel cleaning robot to perform the edge detection anti-falling task when detecting and finding the edge of the photovoltaic panel based on the anti-falling method and the edge state signal of the ranging sensor.

[0076] The solution of the present invention provides an anti-falling method for a photovoltaic panel cleaning robot, which is used to perform the edge detection anti-falling task based on the anti-falling system of the above-mentioned photovoltaic panel cleaning robot; the anti-falling method includes the following steps:

[0077] A1. Obtain the edge state signal of the ranging sensor;

[0078] A2. Determine whether the backward condition is satisfied according to the edge state signal of the ranging sensor. If so, generate a backward instruction and transmit it to the message queue, and enter A7; otherwise, enter A3;

[0079] The backward condition is that the edge state signals of the front sensor 1, the left front sensor 3, and the right front sensor 2 are all in the state outside the solar photovoltaic panel; in this solution, when the edge state signals of the front sensor 1, the left front sensor 3, and the right front sensor 2 are all in the state outside the solar photovoltaic panel, it indicates that the front side of the robot has exceeded the edge of the solar photovoltaic panel. After determining the backward condition, generate a backward instruction to reverse the motor to prevent the robot from continuing to move forward. Among them, the reverse speed is controlled by adjusting the PWM duty cycle to ensure that the robot gradually moves away from the edge area.

[0080] A3. Determine whether the forward condition is satisfied based on the edge status signal of the ranging sensor. If so, generate a forward command, transmit it to the message queue, and proceed to A7; otherwise, proceed to A4.

[0081] The forward condition is that the edge status signals of the front sensor 1, the left front sensor 3, and the right front sensor 2 all correspond to the state within the solar photovoltaic panel, or the edge status signals of the left front sensor 3, the right front sensor 2, the left rear sensor 6, and the right rear sensor 4 all correspond to the state within the solar photovoltaic panel.

[0082] A4. Determine whether the cross-seam forward condition is satisfied based on the edge status signal of the ranging sensor. If so, generate a forward command, transmit it to the message queue, and proceed to A7; otherwise, proceed to A5.

[0083] The cross-seam forward condition is that while the edge status signals of the left front sensor 3 and the right front sensor 2 both correspond to the state outside the solar photovoltaic panel, the edge status signal of the front sensor 1 corresponds to the state within the solar photovoltaic panel.

[0084] A5. Determine whether the right-turn condition is satisfied based on the edge status signal of the ranging sensor. If so, generate a right-turn command, transmit it to the message queue, and proceed to A7; otherwise, proceed to A6.

[0085] The right-turn condition is that the edge status signals of the left front sensor 3 and the left rear sensor 6 both correspond to the state outside the solar photovoltaic panel, or the edge status signal of the left front sensor 3 corresponds to the state within the solar photovoltaic panel and the edge status of the right rear sensor 4 corresponds to the state outside the solar photovoltaic panel.

[0086] A6. Determine whether the left-turn condition is satisfied based on the edge status signal of the ranging sensor. If so, generate a left-turn command, transmit it to the message queue, and proceed to A7; otherwise, proceed to A8.

[0087] The left-turn condition is that the edge status signals of the right front sensor 2 and the right rear sensor 4 both correspond to the state outside the solar photovoltaic panel, or the edge status signal of the right front sensor 2 corresponds to the state within the solar photovoltaic panel and the edge status of the left rear sensor 6 corresponds to the state outside the solar photovoltaic panel.

[0088] A7. Control the motor movement of the photovoltaic panel cleaning robot according to the action command in the message queue, so that the photovoltaic panel cleaning robot performs the corresponding action.

[0089] A8. Repeat A1 - A7 until the photovoltaic panel cleaning robot completes the execution of the planned complete cleaning path, and then completes the execution of the edge detection and anti-fall task.

[0090] In this embodiment, when the photovoltaic panel cleaning robot performs a left-turn action or a right-turn action once, the rotation angle range is greater than 0° and less than 90°. Based on the setting of the rotation angle in this solution, combined with the above methods A1 - A8, the photovoltaic panel cleaning robot can adapt to solar photovoltaic panels with any edge shape.

[0091] In this solution, after each action is completed, the system does not directly exit the current control logic, but continuously obtains the change of the edge status signal of the ranging sensor. When any sensor in the ranging sensor triggers a new sensor state, corresponding action instructions will be generated according to the logic execution process, and the motor movement of the photovoltaic panel cleaning robot will be controlled through the message queue, so that the photovoltaic panel cleaning robot performs the corresponding actions, ensuring that the robot can continuously and stably execute the next task until the edge detection and anti-fall task is completed.

[0092] In this embodiment, based on the above solution, the photovoltaic panel cleaning robot can record the entire maximum peripheral edge path of the photovoltaic panel in the clockwise direction after reaching the edge of the photovoltaic panel, so as to detect and find the complete edge of the solar photovoltaic panel. After detecting the complete edge of the solar photovoltaic panel, it can provide a basis for the photovoltaic panel cleaning robot to establish a cleaning map and prevent it from falling when performing the task of cleaning the photovoltaic panel.

[0093] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention.

Claims

1. A photovoltaic panel cleaning robot anti-fall system, characterized in that: include: The sensor monitoring module is used to collect distance signals through a distance measuring sensor provided on the photovoltaic panel cleaning robot; A hysteresis comparison module is used to perform hysteresis comparison on the distance signal according to the upper threshold of the distance signal and the lower threshold of the distance signal, define a hysteresis loop area, and generate an edge state signal of the distance measuring sensor; The hysteresis comparison module comprises: A threshold definition submodule is used to define an upper threshold of a distance signal and a lower threshold of a distance signal; The edge judgment submodule is used to compare the size relationship between the distance signal and the upper threshold of the distance signal and the lower threshold of the distance signal to obtain the edge detection result of the distance measuring sensor, wherein, if the distance signal is greater than the upper threshold of the distance signal, the edge detection result is that a valid edge is detected; if the distance signal is less than the lower threshold of the distance signal, the edge detection result is that no edge is detected; if the distance signal is less than the upper threshold of the distance signal and greater than the lower threshold of the distance signal, the edge detection result is edge detection noise fluctuation; The hysteresis region submodule is used to define the hysteresis region of the quantized edge detection noise fluctuations; An edge detection submodule, for generating an edge state signal of the distance sensor based on the edge detection result and the hysteresis region, wherein the edge state signal corresponds to a state of being inside the solar photovoltaic panel or a state of being outside the solar photovoltaic panel; The anti-fall module is used to control the photovoltaic panel cleaning robot to perform edge detection and anti-fall tasks based on the edge state signal of the ranging sensor according to the anti-fall method.

2. The anti-fall system of the photovoltaic panel cleaning robot according to claim 1, characterized in that: The ranging sensors on the photovoltaic panel cleaning robot include a left front sensor, a right front sensor, a left rear sensor, a right rear sensor, a front sensor and a rear sensor; the distance between the front sensor and the line connecting the left front sensor and the right front sensor is greater than the gap between the solar photovoltaic panels, and the distance between the rear sensor and the line connecting the left rear sensor and the right rear sensor is greater than the gap between the solar photovoltaic panels.

3. The anti-fall system of the photovoltaic panel cleaning robot according to claim 1, characterized in that: The anti-fall module comprises: The task start submodule is used to start the photovoltaic panel cleaning robot and make the photovoltaic panel cleaning robot detect and find the edge of the photovoltaic panel; The instruction definition submodule is used to define the action instructions of the photovoltaic panel cleaning robot, wherein the action instructions include forward instruction, backward instruction, left turn instruction and right turn instruction; The instruction generation submodule is used to generate corresponding photovoltaic panel cleaning robot action instructions according to the edge state signal of the ranging sensor; The instruction execution submodule is used to control the motor movement of the photovoltaic panel cleaning robot according to the action instruction of the photovoltaic panel cleaning robot, so that the photovoltaic panel cleaning robot performs a forward action, a backward action, a left turn action or a right turn action; The anti-fall submodule is used to control the photovoltaic panel cleaning robot to perform edge detection and anti-fall tasks when detecting and searching for the edge of the photovoltaic panel based on the edge state signal of the ranging sensor according to the anti-fall method.

4. A method for preventing a photovoltaic panel cleaning robot from falling, characterized in that: The anti-fall system of the photovoltaic panel cleaning robot according to any one of claims 1 to 3 is used to perform edge detection and anti-fall tasks; the anti-fall method comprises the following steps: A1. Obtain the edge status signal of the ranging sensor; A2, determine whether the retreat condition is met according to the edge state signal of the ranging sensor, if so, generate a retreat instruction and transmit it to the message queue, enter A7, otherwise enter A3; A3, judging whether the forward condition is met according to the edge state signal of the ranging sensor, if so, generating a forward instruction and transmitting it to the message queue, entering A7, otherwise entering A4; A4, judging whether the conditions for advancing across the seam are met according to the edge state signal of the distance measuring sensor, if so, generating an advance instruction and transmitting it to the message queue, entering A7, otherwise entering A5; A5. Determine whether the right turn condition is met according to the edge state signal of the ranging sensor. If so, generate a right turn instruction and transmit it to the message queue to enter A7. Otherwise, enter A6. A6, judging whether the left turn condition is met according to the edge state signal of the ranging sensor, if so, generating a left turn instruction and transmitting it to the message queue, entering A7, otherwise entering A8; A7. According to the action instructions in the message queue, the motor movement of the photovoltaic panel cleaning robot is controlled so that the photovoltaic panel cleaning robot performs the corresponding action; A8. Repeat A1-A7 until the photovoltaic panel cleaning robot completes the planned complete cleaning path and completes the edge detection and anti-falling task.

5. The anti-falling method of the photovoltaic panel cleaning robot according to claim 4, characterized in that: The retreat condition is that the edge state signals of the front sensor, the left front sensor and the right front sensor all correspond to being outside the solar photovoltaic panel; The forward condition is that the edge state signals of the front sensor, the left front sensor, and the right front sensor all correspond to the state inside the solar photovoltaic panel, or the edge state signals of the left front sensor, the right front sensor, the left rear sensor, and the right rear sensor all correspond to the state inside the solar photovoltaic panel; The cross-slit advancing condition is that the edge state signals of the left front sensor and the right front sensor correspond to the state outside the solar photovoltaic panel, while the edge state signal of the front sensor corresponds to the state inside the solar photovoltaic panel; The right turn condition is that the edge state signals of the left front sensor and the left rear sensor both correspond to being outside the solar photovoltaic panel, or the edge state signal of the left front sensor corresponds to being inside the solar photovoltaic panel and the edge state of the right rear sensor corresponds to being outside the solar photovoltaic panel; The left turn condition is that the edge state signals of the right front sensor and the right rear sensor both correspond to being outside the solar photovoltaic panel, or the edge state signal of the right front sensor corresponds to being inside the solar photovoltaic panel and the edge state of the left rear sensor corresponds to being outside the solar photovoltaic panel.

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