Cleaning robot carpet recognition method

Abstract

The application provides a carpet recognition method for a cleaning robot, the cleaning robot comprising a sleeve and an ultrasonic sensor fixed in the sleeve, the recognition method comprising: setting a standard echo signal of a normal ground; controlling the ultrasonic sensor to vertically emit an ultrasonic signal to a current ground and receive an actual echo signal reflected by the current ground; judging whether the actual echo signal is different from the standard echo signal, and if so, recognizing the current ground as a carpet surface. The method can improve the accuracy and precision of carpet recognition.

Description

[0001] This application is a divisional application of Chinese patent application number CN202010125236.3, the original application date being February 27, 2020, and the publication date being August 27, 2021. Technical Field

[0002] This invention relates to the field of smart homes, and more specifically, to a method for carpet recognition by a cleaning robot. Background Technology

[0003] In recent years, with the rapid development of computer technology and artificial intelligence, intelligent robot technology has gradually become a hot topic in the field of modern robotics research. Among them, the robotic vacuum cleaner, as one of the most practical intelligent robots, can automatically complete the task of cleaning the floor with a certain degree of artificial intelligence. The development direction of robotic vacuum cleaners will be towards better cleaning effects, higher cleaning efficiency, and larger cleaning area brought about by more advanced artificial intelligence.

[0004] Currently, more and more families are installing carpets. Since robotic vacuum cleaners use different cleaning modes on carpets and normal floors, carpet recognition is necessary. Existing smart robotic vacuum cleaners generally use a single cliff-sensing infrared sensor to identify carpets, but this infrared sensor is easily affected by material color or ambient light, resulting in low recognition accuracy.

[0005] Therefore, during the long-term research and development, the inventors conducted extensive research on the structure of cleaning robots and proposed a carpet recognition method for cleaning robots to solve one of the aforementioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide a carpet recognition method for cleaning robots, which can solve at least one of the aforementioned technical problems. The specific solution is as follows:

[0007] According to a specific embodiment of the present invention, the present invention provides a carpet recognition method for a cleaning robot, wherein the cleaning robot includes a sleeve and an ultrasonic sensor, and the recognition method includes:

[0008] The ultrasonic sensor is controlled to emit ultrasonic signals toward the ground and to receive the actual echo signals reflected by the ground.

[0009] Based on the difference between the actual echo signal and the standard echo signal, it is determined whether the current ground surface is a carpet surface;

[0010] The sleeve included in the cleaning robot has a hollow structure;

[0011] Furthermore, the sleeve is used to increase the deviation between the standard echo signal and the actual echo signal generated on the carpet surface, thereby improving the accuracy and precision of the recognition results when the cleaning robot implements the carpet recognition method.

[0012] In some embodiments, the standard echo signal includes an echo signal formed by reflection from the normal ground and then reflected within the sleeve.

[0013] In some embodiments, the standard echo signal is configured in the following ways:

[0014] According to the factory standard settings of the cleaning robot, the standard echo waveform of a normal ground surface is obtained.

[0015] In some embodiments, the standard echo signal setting method further includes:

[0016] Based on the actual cleaning performance of the cleaning robot on a designated normal surface, the standard echo waveform is adjusted through intelligent learning.

[0017] In some embodiments, adjusting the standard echo waveform through intelligent learning based on the actual cleaning performance of the cleaning robot on a designated normal surface includes:

[0018] A room map is pre-created, which includes at least one area;

[0019] Control the ultrasonic sensor to emit ultrasonic signals toward a designated normal ground surface and receive the designated reflected echoes;

[0020] By intelligently learning the specified echo and adjusting the standard echo waveform, a standard echo waveform for each region is generated and automatically saved at the corresponding location on the room map.

[0021] In some embodiments, the standard echo signal is configured in the following ways:

[0022] Provide users with a learning mode and guide them to collect echo data from normal ground surfaces and carpet surfaces;

[0023] Based on the echo data of the normal ground and the echo data of the carpet surface, the standard echo signal of the normal ground is obtained.

[0024] In some embodiments, the sleeve is disposed at the bottom of the cleaning robot.

[0025] In some embodiments, the sleeve is disposed at the front end of the cleaning robot.

[0026] In some embodiments, the standard echo signal is configured in the following ways:

[0027] The echo data of the normal ground and the echo data of the carpet surface are compared with the factory standard data of the cleaning robot to determine whether the echo data of the normal ground and the echo data of the carpet surface exceed the preset error range.

[0028] If the echo data of the normal floor and the echo data of the carpet surface exceed the preset error range, the echo data of the normal floor and the echo data of the carpet surface will be adjusted according to the factory standard data.

[0029] Based on the adjusted echo data of the normal ground surface and the echo data of the carpet surface, the standard echo signal of the normal ground surface is obtained.

[0030] In some embodiments, identifying whether the current ground surface is a carpet surface based on the difference between the actual echo signal and the standard echo signal includes:

[0031] Determine whether the number of peaks in the actual echo signal is less than the number of peaks in the standard echo signal; if it is less, then identify the current ground surface as a carpet surface.

[0032] In some embodiments, identifying whether the current ground surface is a carpet surface based on the difference between the actual echo signal and the standard echo signal includes:

[0033] Based on multiple actual echo signals already received on the current ground, the currently received actual echo signal is adjusted through intelligent learning;

[0034] Determine whether the adjusted actual echo signal is different from the standard echo signal.

[0035] In some embodiments, the sleeve is directly formed in the body of the cleaning robot.

[0036] In some embodiments, the sleeve is a cylinder.

[0037] In some embodiments, identifying whether the current ground surface is a carpet surface based on the difference between the actual echo signal and the standard echo signal includes:

[0038] The received actual echo signal is then denoised.

[0039] Determine whether the actual echo signal after denoising is different from the standard echo signal.

[0040] In some embodiments, identifying whether the current ground surface is a carpet surface based on the difference between the actual echo signal and the standard echo signal includes:

[0041] If the ultrasonic signal reflected from the ground is scattered at the bottom edge of the sleeve, then the received actual echo signal is subjected to waveform compensation processing.

[0042] Compared with the prior art, the above-described solution of the present invention achieves multiple echoes from a normal surface by setting a downward-emitting ultrasonic sensor on the lower front side of the cleaning robot and fixing the ultrasonic sensor in a sleeve. This results in a greater deviation between the ultrasonic echo waveform of the normal surface and the ultrasonic echo waveform of the carpet surface, thus improving the accuracy and precision of the cleaning robot in identifying carpets during the cleaning process. Attached Figure Description

[0043] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0044] Figure 1A A top view schematic diagram of a cleaning robot according to an embodiment of the present invention is shown;

[0045] Figure 1B A bottom-view schematic diagram of a cleaning robot according to an embodiment of the present invention is shown;

[0046] Figure 2 A perspective view of a fixing unit after the sleeve and washer are assembled according to an embodiment of the present invention is shown;

[0047] Figure 3 It is shown in accordance with Figure 1A and 1B A perspective view of the cleaning robot with a cylindrical opening at the front bottom is shown;

[0048] Figure 4A The diagram illustrates the echo waveforms received from a normal ground by two ultrasonic sensors, one with a sleeve and the other without, according to an embodiment of the present invention.

[0049] Figure 4B The diagram shows echo waveforms received from a carpet surface by two ultrasonic sensors, one with a sleeve and the other without, according to an embodiment of the present invention.

[0050] Figure 5 A perspective view of an ultrasonic sensor assembled into a fixing unit according to an embodiment of the present invention is shown;

[0051] Figure 6A perspective view of an ultrasonic sensor fixed in a cover plate according to an embodiment of the present invention is shown.

[0052] Figure 7 A flowchart illustrating a carpet recognition method for a cleaning robot according to an embodiment of the present invention is shown;

[0053] Figure 8 A flowchart illustrating a method for a cleaning robot to adjust the standard echo waveform based on the actual cleaning performance of the cleaning robot on a designated normal surface according to an embodiment of the present invention is shown.

[0054] Figure 9 A flowchart illustrating a method for a cleaning robot to acquire a standard echo signal of a normal floor based on echo data from the normal floor and echo data from a carpet surface, according to an embodiment of the present invention, is shown. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0056] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0057] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0058] It should be understood that although the terms first, second, third, etc., may be used to describe... in the embodiments of the present invention, these... should not be limited to these terms. These terms are only used to distinguish... For example, first... may also be referred to as second... without departing from the scope of the embodiments of the present invention, and similarly, second... may also be referred to as first...

[0059] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0060] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0061] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0062] Example 1

[0063] Figure 1A and 1B This is a schematic diagram illustrating the structure of a cleaning robot 10 according to an exemplary embodiment. Figure 1A An exemplary top view of the cleaning robot 10 is shown. Figure 1B An exemplary bottom view of the cleaning robot 10 is shown. Figure 1A and Figure 1B As shown, the cleaning robot 10 includes: a robot body 1, a control unit (not shown in the figure), a fixing unit 2, and an ultrasonic sensor 3.

[0064] The robot body 1 forms the outer shell of the cleaning robot 10 and houses other components, such as other sensing units, drive units, cleaning units, energy units, and human-machine interaction units. These units are not illustrated; any existing cleaning robot components can be integrated onto the robot body of this invention to complete the overall operation of the cleaning robot 10 described in this embodiment. The integration or positional relationship of these units can be obtained with reference to existing technologies and will not be elaborated here. Optionally, the robot body is a flattened cylinder, and further, the bottom edge of the cylinder is chamfered to enable obstacle-crossing functionality.

[0065] The control unit is located within the robot body 1, specifically on a circuit board within the robot body 1. The control unit includes a processor, which can comprehensively determine the current ground condition based on the echo signals fed back from the sensing units. Optionally, the processor is an MCU (Microcontroller Unit) or an AP (Analog Processing Unit).

[0066] The aforementioned floor surfaces include normal floors and carpeted surfaces. Normal floors include smooth surfaces such as wood flooring, floor tiles, and ceramic tiles. Carpeted surfaces refer to floor surfaces covered with carpet; here, "carpet" can be interpreted broadly to include items containing plush materials such as clothing and other soft objects.

[0067] The fixing unit 2 is located at the front of the chassis of the robot body 1 and is used to fix the ultrasonic sensor 3, facilitating immediate judgment of the ground shape. Specifically, the fixing unit 2 includes a sleeve 21, which is a hollow cylinder with open sides. The central axis of the hollow cylinder is perpendicular to the ground. This structure allows the echo signal of the ultrasonic sensor 3 to undergo uniform diffuse reflection within the hollow cylinder, thereby fixing the return time of the echo signal. Optionally, such as... Figure 2 As shown, the sleeve is a cylinder directly opened at the bottom front end of the robot body 1. If the bottom of the ultrasonic sensor 3 is exposed through the cylinder, a hollow cylinder of the same size can be added to the bottom of the main cylinder. This sleeve structure can save manufacturing costs and installation time. In other embodiments, the sleeve 21 and the robot body 1 can be two independent structures, and these two structures are assembled.

[0068] Preferably, the surface of the sleeve 21 facing the ground is flat, i.e., parallel to the ground, which allows it to receive more effective echoes during cleaning. However, in some embodiments, the chassis edge of the cleaning robot 10 has a chamfer. To conform to the overall shape of the cleaning robot 10, the flat surface of the sleeve 21 facing the ground needs to be set to the same shape as the chamfer; otherwise, the flat sleeve 21 is easily damaged during the movement of the cleaning robot 10. Optionally, the bottom edge of the sleeve 21 is set as a slope.

[0069] like Figure 3 As shown, the ultrasonic sensor 3 is fixed inside the sleeve 21 and electrically connected to the control unit. The ultrasonic sensor 3 is used to transmit ultrasonic signals to the ground and receive echo signals reflected from the ground. The ultrasonic sensor 3 is also used to send the received echo signals to the control unit. The type of ultrasonic sensor can be selected according to actual needs and is not limited here.

[0070] Optionally, the ultrasonic sensor 3 has two metal plugs 31 on its top, which are used for electrical connection with the control unit for signal transmission. Specifically, the connection can be made via wiring. In other embodiments, the top of the ultrasonic sensor 3 may have gold fingers (not shown in the figure), which consist of multiple gold-colored conductive contacts. The signal from the ultrasonic sensor 3 can be transmitted to the control unit through these gold fingers.

[0071] In an exemplary embodiment of the present invention, by fixing the ultrasonic sensor 3 inside the sleeve 21, the accuracy of the cleaning robot in identifying carpets can be improved. Below, through... Figure 4A and Figure 4B Explain the specific principles behind improving carpet recognition accuracy. Figure 4A The example shows the echo waveforms received from a normal ground by two ultrasonic sensors, one with a sleeve and the other without. Figure 4B The illustrations exemplify the echo waveforms received from a carpet surface by ultrasonic sensors with and without sleeves. Figure 4A As shown, without the sleeve 21 surrounding the ultrasonic sensor 3, i.e., with the ultrasonic sensor 3 exposed, the control unit controls the ultrasonic sensor 3 to emit ultrasonic signals towards the normal ground and receive echoes. Similarly, with the sleeve 21 surrounding the ultrasonic sensor 3, the control unit controls the ultrasonic sensor 3 to emit ultrasonic signals towards the normal ground and receive echoes, receiving 6 to 10 echo peaks. Compared to the ultrasonic sensor 3 without the sleeve 21, the ultrasonic sensor 3 with the sleeve 21 achieves multiple echoes from the normal surface. Figure 4B As shown, the ultrasonic sensors 3 with and without sleeves reflect off the carpet surface. Since the ultrasonic waves are almost completely absorbed by the carpet, the reflections of both types of echoes are short, with only 1-2 peaks.

[0072] Therefore, based on the above... Figure 4A and 4B The comparison shows that, with the sleeve in place, the ultrasonic echo waveform on a normal surface deviates more from that on a carpet surface, which greatly improves the accuracy and precision of carpet identification.

[0073] Furthermore, the fixing unit 2 includes a fixing part 22, which is used to fix the ultrasonic sensor 3 inside the sleeve 21. Optionally, the fixing part 22 is a step located on the inner wall of the sleeve 21 and is an integral structure of the sleeve 21 formed by injection molding. The step can support the ultrasonic sensor 3, thereby achieving fixation. The shape of the step matches the shape of the ultrasonic sensor 3, and is not specifically limited. Of course, the fixing part 22 is not limited to being inside the sleeve 21, but can also be outside the sleeve 21, as long as it can prevent the ultrasonic sensor 3 from falling off.

[0074] Optionally, the fixing unit 2 further includes a fixed anchor point 23 and a movable anchor point 24, which are spaced apart on the outer side of the top of the sleeve 21 for fixing the ultrasonic sensor 3.

[0075] Optional, such as Figure 5 As shown, the fixing unit 2 also includes a washer 25, which is disposed at the contact position between the fixing part 22 and the ultrasonic sensor 3. Specifically, when installing the ultrasonic sensor 3, the washer 25 is placed on the step first, and then the ultrasonic sensor 3 is placed. In this way, when the cleaning robot 10 performs the cleaning task, the washer 25 can play a shock-absorbing role, thereby extending the service life of the ultrasonic sensor 3.

[0076] Optional, such as Figure 6 As shown, the fixing unit 2 includes a cover plate 26, which is placed on top of the ultrasonic sensor 3 for fixing the ultrasonic sensor 3 from above. Specifically, the cover plate 26 is provided with screw holes 260 for fixing the ultrasonic sensor 3 with screws. Optionally, the cover plate 26 is also provided with a first groove / hole 261 corresponding to the fixed anchor point 23 and a second groove / hole 262 corresponding to the movable anchor point 24. The first groove / hole 261 matches the fixed anchor point 23 precisely and is fixed after installation. The second groove / hole 262 is used to accommodate the movable anchor point 24 and allows the movable anchor point 24 to be finely adjusted within the second groove / hole 262 to facilitate the installation of the screws. After installation, the cover plate 26 is fixedly connected to the robot body 1. The shape of the cover plate 26 is not limited and can be selected according to the internal structure of the ultrasonic sensor or the robot body.

[0077] Optionally, the cover plate 26 is further provided with a connection opening 263, which is used for electrical connection between the ultrasonic sensor 3 and the control unit. When the cover plate 26 is fixed to the top of the ultrasonic sensor 3, the metal plug or gold finger on the top of the ultrasonic sensor 3 can be electrically connected to the control unit through the connection opening 263.

[0078] Optionally, the upper surface of the cover plate 26 is provided with reinforcing ribs 264. These reinforcing ribs 264 can strengthen the structure of the cover plate 26 and also support other sensors of the cleaning robot 10. For example, some of the reinforcing ribs 264 can be configured as side-curved surfaces to facilitate the fixing of obstacle sensors (not shown in the figure) located directly in front of the robot body 1. Of course, the specific structure of the reinforcing ribs can be processed according to the shape of other sensors, and there are no restrictions here.

[0079] It should be noted that the cleaning robot 10 can be not only a sweeping robot or a mopping robot, but also other intelligent robots with autonomous walking mechanisms that need to recognize the ground shape.

[0080] Finally, the cleaning robot 10 provided in this embodiment of the invention achieves multiple echoes from a normal surface by setting a downward-emitting ultrasonic sensor on the lower front side and fixing the ultrasonic sensor in a sleeve. This makes the ultrasonic echo waveform of the normal surface deviate more from the ultrasonic echo waveform of the carpet surface, thereby improving the accuracy and precision of the cleaning robot in identifying carpets.

[0081] Example 2

[0082] Please see Figure 7 This illustration shows an exemplary embodiment of a carpet recognition method for a cleaning robot. The carpet recognition method for a cleaning robot in this embodiment is applied to... Figure 1A and 1B The cleaning robot shown. Figure 7 As shown, the carpet recognition method for the cleaning robot includes the following steps:

[0083] S71, set a standard echo signal for a normal ground surface; wherein, the standard echo signal includes signals that can characterize sound waves, such as standard echo waveform and standard echo peak count.

[0084] Optionally, before the cleaning robot performs the cleaning task, the standard echo waveform of the normal floor is obtained according to the factory standard settings of the cleaning robot. The factory standard includes echo characteristics of the normal floor based on user big data, and may also include echo characteristics of carpeted floors, such as the number of echo peaks, to more accurately set the standard echo signal for the normal floor.

[0085] Optionally, based on obtaining the standard echo waveform of a normal surface according to factory standards, setting the standard echo signal for the normal surface further includes: adjusting the standard echo waveform through intelligent learning based on the actual cleaning performance of the cleaning robot on the designated normal surface. Specifically, as shown... Figure 8 As shown, the step of adjusting the standard echo waveform through intelligent learning based on the actual cleaning performance of the cleaning robot on a designated normal surface includes:

[0086] S711, A room map is pre-established, which includes at least one area. If multiple areas are included, the echo waveform corresponding to each area is the standard echo waveform. Of course, a room map can also be omitted, and the entire room can be considered as one area.

[0087] S712, control the ultrasonic sensor to emit ultrasonic signals towards a designated normal surface and receive the reflected designated echoes. Specifically, the user places the cleaning robot on a normal surface in the room and performs one or more cleaning cycles, receiving one or more designated echoes. The designated normal surface is a normal surface subjectively selected by the user to be cleaned, and the designated echo is the echo corresponding to the designated normal surface.

[0088] S713, by intelligently learning the specified echo and adjusting the standard echo waveform, generates a standard echo waveform for each area and automatically saves it to the corresponding position on the room map. It is understood that the standard echo waveform set for a normal floor can be adjusted according to the actual condition of the floor used by the user. As the number of cleaning sessions increases, the standard waveform will automatically learn and be saved on the corresponding room map.

[0089] Optionally, the standard echo signal for setting the normal floor surface is a user-defined signal. Specifically, setting the standard echo signal for setting the normal floor surface includes: providing a learning mode to the user and guiding the user to collect echo data from the normal floor surface and the carpet surface; and obtaining the standard echo signal for the normal floor surface based on the echo data from the normal floor surface and the carpet surface. Guiding the user to collect the echo data from the carpet surface is to further and more accurately determine the critical values ​​of the standard echo signal for the normal floor surface, such as the minimum number of peaks and the roughness of the standard echo waveform.

[0090] To avoid significant errors during the user's learning process, which could prevent the cleaning robot from activating its carpet mode, further judgment can be made using factory standard data to obtain standard echo signals from normal floor surfaces, thereby achieving more accurate carpet identification. Please refer to [link / reference]. Figure 9The step of obtaining the standard echo signal of the normal ground based on the echo data of the normal ground and the echo data of the carpet surface includes:

[0091] S714, compare the echo data of the normal ground surface and the echo data of the carpet surface with the factory standard data of the cleaning robot, and determine whether the echo data of the normal ground surface and the echo data of the carpet surface exceed the preset error range. The preset error range is set according to actual conditions and is not limited here.

[0092] S715, if the echo data of the normal ground and the echo data of the carpet surface exceed the preset error range, then the echo data of the normal ground and the echo data of the carpet surface are adjusted according to the factory standard data. For example, if the preset error range is set to 1-2, and the user collects 11 echo peaks from the normal ground, while the factory standard data shows 5-9 echo peaks from the normal ground, then the user-collected normal ground echo data is determined to be incorrect.

[0093] S716, Based on the adjusted echo data of the normal ground and the echo data of the carpet surface, obtain the standard echo signal of the normal ground.

[0094] S72, control the ultrasonic sensor to vertically transmit ultrasonic signals to the current ground and receive the actual echo signals reflected by the current ground;

[0095] Specifically, after setting the standard echo signal of the normal ground, the control unit controls the transmission of an electrical signal to the ultrasonic sensor. The ultrasonic sensor converts the electrical signal into an ultrasonic signal and transmits it downwards to the ground. The ultrasonic signal is reflected by the ground, received by the ultrasonic sensor, converted into an electrical signal, and transmitted to the control unit.

[0096] S73, determine whether the actual echo signal is different from the standard echo signal. If there is a difference, identify the current ground as a carpet surface.

[0097] In this step, determining whether the actual echo waveform differs from the standard echo signal to identify whether the current ground surface is a carpet surface includes:

[0098] The system determines whether the number of peaks in the actual echo signal is less than the number of peaks in the standard echo signal. If the number of peaks in the actual echo signal is less than the number of peaks in the standard echo signal, the current floor surface is identified as a carpet surface. Specifically, for different areas, the actual echo signal can be compared separately with the standard echo signal corresponding to the current area to improve the accuracy of carpet identification.

[0099] Optionally, the actual echo signal can be adjusted before the judgment and recognition process. Specifically, based on multiple received actual echo signals from the current ground, the currently received actual echo signal is adjusted through intelligent learning. This can be understood as the cleaning robot performing multiple recognitions based on the user's ground surface and automatically learning the actual echo signal received each time to improve the accuracy of carpet recognition.

[0100] Optionally, if the ultrasonic signal reflected from the ground is scattered at the bottom edge of the sleeve, waveform compensation processing is performed on the received actual echo signal. This can be understood as follows: when the bottom edge of the sleeve is a slope, the echo reflected from the ground will be scattered to a certain extent at the slope. Therefore, waveform compensation processing can be performed on the received actual echo signal before identification. Specific waveform compensation methods include: setting an amplitude threshold; and weighting and compensating for peaks smaller than the amplitude threshold to make the actual echo signal consistent with the actual echo signal received when the bottom edge is a plane. Of course, this method is not limited to any specific method; any method that makes the actual echo signal consistent with the actual echo signal received when the bottom edge is a plane is acceptable.

[0101] Optionally, the cleaning robot will emit operating noise during operation, such as from the fan, main brush rotation, side brush rotation, and wheel movement. This noise can affect the judgment of the actual echo signal, therefore, noise reduction processing of the actual echo signal is required. Optionally, the control unit can perform median filtering on the received actual echo signal. In other embodiments, the ultrasonic signal emitted by the ultrasonic sensor can be encoded, and operating noise in the actual echo signal can be removed based on the encoding. The specific noise reduction process can be found in existing noise reduction methods, and will not be elaborated here.

[0102] Furthermore, when the current floor surface is identified as a carpet surface, the control unit can control the cleaning robot to execute a carpet mode, such as increasing the suction power of the fan to better clean the carpet; or, if the cleaning robot has a mopping function, the control unit can control the cleaning robot to raise the mopping tool or stop it from working to prevent the carpet from getting wet.

[0103] Finally, the carpet recognition method for the cleaning robot provided in this embodiment of the invention solves the problems of low accuracy and poor recognition effect of infrared sensors for carpets by setting a downward ultrasonic sensor below the front end of the robot, and using ultrasonic waves to detect the ground condition. If the detection result is a carpet, the action mode of the cleaning robot is adjusted. This improves the accuracy and precision of the cleaning robot in recognizing carpets.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A method for carpet recognition by a cleaning robot, characterized in that, The cleaning robot includes a sleeve and an ultrasonic sensor, and the identification method includes: The ultrasonic sensor is controlled to emit ultrasonic signals toward the ground and to receive the actual echo signals reflected by the ground. Based on the difference between the actual echo signal and the standard echo signal, it is determined whether the current ground surface is a carpet surface; The cleaning robot includes a hollow sleeve, and the ultrasonic sensor is fixed inside the sleeve. Furthermore, the sleeve is used to cause the ultrasonic sensor to generate multiple echoes on a normal ground surface, thereby increasing the deviation between the standard echo signal and the actual echo signal generated on the carpet surface. The step of identifying whether the current ground surface is a carpet surface based on the difference between the actual echo signal and the standard echo signal includes: if the number of peaks in the actual echo signal is less than the number of peaks in the standard echo signal, then the current ground surface is identified as a carpet surface.

2. The method according to claim 1, characterized in that, The standard echo signal includes an echo signal formed by reflection from the normal ground and then reflected within the sleeve.

3. The method according to claim 1, characterized in that, The standard echo signal setting method includes: According to the factory standard settings of the cleaning robot, the standard echo waveform of a normal ground surface is obtained.

4. The method according to claim 1, characterized in that, The standard echo signal setting method also includes: Based on the actual cleaning performance of the cleaning robot on a designated normal surface, the standard echo waveform is adjusted through intelligent learning.

5. The method according to claim 4, characterized in that, The step of adjusting the standard echo waveform through intelligent learning based on the actual cleaning performance of the cleaning robot on a designated normal surface includes: A room map is pre-created, which includes at least one area; Control the ultrasonic sensor to emit ultrasonic signals toward a designated normal ground surface and receive the designated reflected echoes; By intelligently learning the specified echo and adjusting the standard echo waveform, a standard echo waveform for each region is generated and automatically saved at the corresponding location on the room map.

6. The method according to claim 1, characterized in that, The standard echo signal can be set in the following ways: Provide users with a learning mode and guide them to collect echo data from normal ground surfaces and carpet surfaces; Based on the echo data of the normal ground and the echo data of the carpet surface, the standard echo signal of the normal ground is obtained.

7. The method according to claim 1, characterized in that, The sleeve is located at the bottom of the cleaning robot.

8. The method according to claim 1, characterized in that, The sleeve is located at the front end of the cleaning robot.

9. The method according to claim 1, characterized in that, The sleeve is directly cut into the body of the cleaning robot.

10. The method according to claim 1, characterized in that, The sleeve is a cylinder.

11. A cleaning robot, characterized in that, include: A sleeve, which has a hollow structure, is disposed at the bottom or front end of the cleaning robot; An ultrasonic sensor is fixed inside the sleeve and electrically connected to the control unit; A control unit for performing the carpet recognition method for a cleaning robot as described in any one of claims 1-10.

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