Recharging control method and system for mobile robot, and computer program product

Abstract

The present application relates to a recharging control method and system for a mobile robot, and a computer program product. The recharging control method comprises the following steps: when a mobile robot needs to be recharged, and upon a preset movement condition being met, controlling the mobile robot to move to a first preset location; controlling the mobile robot to rotate at the first preset location, and determining whether the mobile robot is able to acquire a first recharging signal; if the mobile robot is unable to acquire the first recharging signal, determining whether the mobile robot is able to acquire a second recharging signal; and if the mobile robot is able to acquire the second recharging signal, guiding the mobile robot to perform recharging according to the second recharging signal. In this way, when a mobile robot is unable to acquire a first recharging signal at a first preset location, the mobile robot can be guided to recharge by means of another recharging signal, such as a second recharging signal. This allows mobile robots to be guided to recharging stations by means of different recharging signals, thereby improving the success rate of mobile robot recharging.

Description

Method and system for return charging control of mobile robot, and computer program product TECHNICAL FIELD

[0001] The present application relates to the technical field of robots, in particular to a method and system for return charging control of a mobile robot, and a computer program product. BACKGROUND

[0002] When the mobile robot needs to return to a charging station due to insufficient power or other reasons, the mobile robot can autonomously move to the charging station and perform operations such as connection to the charging station, monitoring of the charging process, and automatic disconnection after completion of the charging process.

[0003] In general, the mobile robot moves to a preset or previously memorized position, acquires an infrared feature signal of the charging station at the position, locates the charging station based on the infrared feature signal, and then moves to the charging station based on the infrared feature signal to dock and start charging. If the infrared feature signal cannot be acquired at the preset or previously memorized position, the mobile robot acquires a current position based on a positioning sensor such as a gyroscope and an odometer, acquires a position of the charging station based on the current position, and then moves to the charging station to charge.

[0004] However, the positioning sensor such as the gyroscope and the odometer of the mobile robot has cumulative errors, and when the cumulative errors are too large, a large positioning error is caused, resulting in a return charging failure. SUMMARY

[0005] Therefore, it is necessary to provide a method and system for return charging control of a mobile robot, and a computer program product to improve the success rate of return charging.

[0006] In a first aspect, the present application provides a method for return charging control of a mobile robot, comprising the following steps:

[0007] When the mobile robot needs to return to a charging station, if a preset movement condition is met, the mobile robot is controlled to move to a first preset position, the mobile robot is controlled to rotate at the first preset position, and it is determined whether the mobile robot can acquire a first return charging signal. If the mobile robot cannot acquire the first return charging signal, it is determined whether the mobile robot can acquire a second return charging signal. If the mobile robot can acquire the second return charging signal, the mobile robot is guided to return to the charging station based on the second return charging signal.

[0008] In a second aspect, the present application provides a mobile robot back charging control system, comprising: a moving module, configured to control the mobile robot to move to a first preset position when the mobile robot needs to be back charged, if a preset moving condition is met; a rotating module, configured to control the mobile robot to rotate at the first preset position; a first judging module, configured to judge whether the mobile robot can acquire a first back charging signal; a second judging module, configured to judge whether the mobile robot can acquire a second back charging signal, if the first judging module judges that the mobile robot cannot acquire the first back charging signal; and a back charging module, configured to guide the mobile robot to be back charged according to the second back charging signal, if the mobile robot can acquire the second back charging signal.

[0009] In a third aspect, the present application provides a computer program product, which stores computer readable instructions executable by at least one processor to cause the at least one processor to perform the steps of the mobile robot back charging control method.

[0010] The above introduces a mobile robot back charging control method and system, and a computer program product, comprising the following steps: when the mobile robot needs to be back charged, controlling the mobile robot to move to a first preset position if a preset moving condition is met; controlling the mobile robot to rotate at the first preset position, and judging whether the mobile robot can acquire a first back charging signal; if the mobile robot cannot acquire the first back charging signal, judging whether the mobile robot can acquire a second back charging signal; and if the mobile robot can acquire the second back charging signal, guiding the mobile robot to be back charged according to the second back charging signal. Thus, when the mobile robot cannot acquire the first back charging signal at the first preset position, the mobile robot can be guided to be back charged by other back charging signals, such as the second back charging signal, and the mobile robot can be guided to be back charged by different back charging signals, thereby improving the success rate of the mobile robot back charging. BRIEF DESCRIPTION OF DRAWINGS

[0011] FIG. 1 is a structural schematic diagram of a mobile robot back charging control system according to the present application;

[0012] FIG. 2 is a side view structural schematic diagram of a mobile robot according to the present application;

[0013] FIG. 3 is a rear view structural schematic diagram of a mobile robot according to the present application;

[0014] FIG. 4 is a bottom view structural schematic diagram of a mobile robot according to the present application;

[0015] FIG. 5 is a magnetic field strength distribution schematic diagram of a guide line according to an embodiment of the present application;

[0016] FIG. 6 is a flow diagram of a method for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0017] FIG. 7 is a flow diagram of another method for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0018] FIG. 8 is a flow diagram of yet another method for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0019] FIG. 9 is a flow diagram of yet another method for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0020] FIG. 10 is a flow diagram of yet another method for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0021] FIG. 11 is a block diagram of a system for controlling a mobile robot to return to a charging station according to an embodiment of the present application;

[0022] FIG. 12 is a block diagram of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely intended to explain the present application and should not be used to limit the present application.

[0024] Referring to FIG. 1, FIG. 1 is a structural diagram of a system for controlling a mobile robot to return to a charging station, as shown in FIG. 1, the system includes a mobile robot and a charging station, when the mobile robot needs to be charged, the mobile robot will return to the charging station to be charged.

[0025] Referring to FIG. 2, the mobile robot is provided with a visual sensor assembly, an infrared signal receiver and a satellite positioning device (not shown in the figure). The visual sensor assembly is used to detect or perceive the surrounding environment information of the mobile robot, so as to achieve obstacle avoidance, positioning and recharging. Specifically, the visual sensor assembly includes at least one visual sensor (for example, the mobile robot shown in FIGS. 2 and 3, the visual sensor assembly includes a first visual sensor, a second visual sensor and a third visual sensor, the second visual sensor is used to detect the environment information in front of the mobile robot, and the first visual sensor and the third visual sensor are used to detect the environment information on the side of the mobile robot), and the visual sensor can be a monocular or multi-view camera. When the visual sensor detects the characteristic information of the charging station, the characteristic information can be used as a visual recharging signal to guide the mobile robot to return to the charging station. The infrared signal receiver is used to receive the infrared signal sent by the charging station, and guide the mobile robot to move towards the charging station or control the mobile robot to avoid the charging station according to the infrared signal. The infrared signal receiver is located on the front side of the mobile robot and near the visual sensor assembly. Specifically, if the visual sensor is a monocular camera, the infrared signal receiver is arranged near the second visual sensor, and if the visual sensor is a multi-view camera, the infrared signal receiver is arranged between two cameras. More specifically, if the visual sensor is a binocular sensor, the binocular sensor is located on the center axis of the mobile robot or is symmetric about the center axis, and the infrared signal receiver is located between the binocular sensor, which helps to improve the synchronization processing capability of the visual signal and the infrared signal. The satellite positioning device is used to receive satellite signals to guide the mobile robot to move according to the satellite signals, especially when the mobile robot does not receive the characteristic information of the charging station, the infrared signal, and the magnetic field signal (which will be introduced below), the mobile robot is mainly guided to move according to the satellite signals.

[0026] Referring to FIG. 4, FIG. 4 is a structural schematic diagram of the mobile robot viewed from the bottom. As shown in FIG. 4, the chassis of the mobile robot is further provided with a magnetic induction sensor assembly, specifically including a first magnetic induction sensor and a second magnetic induction sensor. Further, the first magnetic induction sensor and the second magnetic induction sensor can be arranged on the front side in the walking direction of the mobile robot, and the first magnetic induction sensor and the second magnetic induction sensor are symmetrically arranged relative to the center axis of the mobile robot, the distance between the first magnetic induction sensor and the second magnetic induction sensor is 7cm-9cm, and the distance between the first magnetic induction sensor and the second magnetic induction sensor from the ground is equal. So that the first magnetic induction sensor and the second magnetic induction sensor can accurately detect the deviation direction of the mobile robot relative to the magnetic field signal generating device.

[0027] Please refer to Fig. 1 again, the charging station is provided with an infrared signal transmitter, the infrared signal transmitter alternately transmits a first infrared signal and a second infrared signal, the first infrared signal and the second infrared signal transmitted by the infrared signal transmitter are received by an infrared signal receiver on the mobile robot to guide the mobile robot to return to the charging station. Wherein, the infrared signal transmitter can be set to alternately transmit the first infrared signal and the second infrared signal at different times or frequencies. Specifically, the time for turning on the second infrared signal can be set to 100 ms, and the time for turning on the first infrared signal can be set to 200 ms; or the first infrared signal is transmitted twice, and then the second infrared signal is transmitted once, whereby the infrared signal receiver can accurately distinguish the second infrared signal from the first infrared signal. It should be pointed out that the difference between the first infrared signal and the second infrared signal lies in that the radiation distances of the two are different, that is, the farthest radiation distances of the first infrared signal, the visual back charging signal and the second infrared signal decrease in turn, and by setting the gradient of the signal radiation distance, the mobile robot can gradually reduce the search range during the back charging process, and finally realize accurate docking with the charging station, thereby improving the accuracy and efficiency of the back charging. For example, the radiation distance of the first infrared signal can be 7 m, the farthest radiation distance of the visual signal can be 3 m, and the radiation distance of the second infrared signal can be 2 m.

[0028] Specifically, as shown in Fig. 1, the area range covered by various different back charging signals guiding the mobile robot to return to charge is shown. The coverage area range of the first infrared signal is area 1, that is, its radiation range covers area 1. The coverage area range of the second infrared signal is area 2, that is, its radiation range covers area 2, and the coverage area of the visual back charging signal is area 3. The mobile robot can detect that the area in which the visual back charging signal can be detected (i.e. the coverage area of the visual back charging signal) has a first intersection with the coverage area of the first infrared signal, and the coverage area of the second infrared signal is in the first intersection.

[0029] That is, under normal circumstances, if the mobile robot is in the range of area 1 excluding area 3, its infrared signal receiver can detect the first infrared signal sent by the charging station; if the mobile robot is in area 3, its visual sensor can detect the visual back charging signal of the charging station, and the mobile robot is guided to return to charge by the visual back charging signal; if the mobile robot is in area 2, its infrared signal receiver can detect the second infrared signal sent by the charging station, and the mobile robot is guided to return to charge by the second infrared signal.

[0030] Wherein, area 1 can be a sector, or petal, or elliptical area with an angle range of 160-180 degrees and a radius of 7-9 m, area 2 can be a sector, or petal, or elliptical area with an angle range of 160-180 degrees and a radius of 1-2 m, and area 3 can be a sector area with an angle range of 160-180 degrees and a radius of 2-3 m.

[0031] Please refer to Fig. 1 again, the charging station further comprises a base for the mobile robot to stop and a guide line for guiding the mobile robot to return to charging, the guide line is arranged on the back or front of the base and is symmetrical about the central axis of the base. Since the guide line is arranged on the base, a closed guide area (the width L of the guide area is about 18-22 cm) is formed by the arrangement of the guide line, and when the central axis of the mobile robot is approximately coincident with the central axis of the base, the first magnetic induction sensor and the second magnetic induction sensor are located in the closed guide area. Since the guide line is in an energized state, a magnetic field signal can be generated near the base of the charging station, and the magnetic induction sensor assembly of the mobile robot detects the magnetic field signal of the guide line within a certain range. Further, the processor of the mobile robot can determine the distance and direction of the mobile robot from the charging station according to the polarity and intensity of the magnetic field signal, and then send a control signal to control the mobile robot to adjust the moving direction so that the central axis of the mobile robot is approximately coincident with the central axis of the base.

[0032] Please refer to Fig. 5, which is a schematic diagram of the magnetic field intensity distribution of the guide line. Assuming that the first magnetic induction sensor is arranged at the right side of the front side of the mobile robot in the walking direction, and the second magnetic induction sensor is arranged at the left side of the front side of the mobile robot in the walking direction, when the intensity of the magnetic field signal detected by the first magnetic induction sensor is weaker than that of the magnetic field signal detected by the second magnetic induction sensor, the mobile robot can be controlled to adjust the position to the left; when the intensity of the magnetic field signal detected by the first magnetic induction sensor is stronger than that of the magnetic field signal detected by the second magnetic induction sensor, the mobile robot can be controlled to adjust the position to the right; when the intensity of the magnetic field signal detected by the first magnetic induction sensor is not much different from that of the magnetic field signal detected by the second magnetic induction sensor (within a preset range), the mobile robot can be controlled to move straight. The mobile robot detects the magnetic field signal in real time and adjusts the walking direction in real time. The mobile robot moves relatively slowly and rotates with a small amplitude when adjusting the direction, so as to make correction at any time.

[0033] Please refer to Fig. 1 again, the coverage area of the magnetic field signal is area 4, and the area of the area 4 is larger than the closed guide area formed by the guide line, because the magnetic field signal can radiate to both sides of the guide line. The coverage area of the visual return-to-charging signal intersects with the coverage area of the magnetic field signal.

[0034] The front side of the mobile robot is further provided with a charging connector, and the charging station further comprises a charging pole, wherein the charging pole is symmetrical about the central axis of the base, and the projection of the end of the charging pole on the base is located in the guide area. When the mobile robot moves along the central axis of the charging station under the guidance of the guide line until the charging connector of the mobile robot touches and connects with the charging pole, the controller of the mobile robot can recognize the charging state of the mobile device and control the mobile robot to stop moving.

[0035] The above is the basic structure of the mobile robot and the charging station, and the mobile robot back charging control method is designed based on the basic structure. Details are described below.

[0036] Referring to FIG. 6, FIG. 6 is a flowchart of a mobile robot back charging control method according to an embodiment of the present application. As shown in FIG. 6, the back charging control method of the embodiment includes the following steps:

[0037] Step S1: When the mobile robot needs to be charged, if the preset movement condition is met, the mobile robot is controlled to move to a first preset position.

[0038] The conditions under which the mobile robot needs to be charged include the following:

[0039] First: the mobile robot determines that its power is insufficient and needs to be charged;

[0040] Second: the mobile robot receives a back charging instruction;

[0041] Third: a key component in the mobile robot fails, such as a wheel or various positioning sensors, affecting the mobile robot to continue working;

[0042] Fourth: the mobile robot completes a work task;

[0043] Fifth: the cleaning device on the charging station needs to clean the mobile robot, such as cleaning the vision sensor on the mobile robot, or cleaning the action wheel of the mobile robot, or cleaning the mowing assembly on the mowing robot, etc.

[0044] Sixth: the storage box on the mobile robot is full, such as the grass in the grass collecting frame of the mowing robot being full.

[0045] The first preset position usually refers to a position where the mobile robot can be successfully charged, and can include any one of the following positions:

[0046] 1. A position about 0-3 meters in front of the charging station and near the central axis of the charging station;

[0047] 2. A position point in the coverage area of the visual back charging signal;

[0048] 3. A position point in the coverage area of the first infrared signal;

[0049] 4. A position point in the magnetic field signal area generated by the guide line;

[0050] 5. A position point in the intersection of the coverage area of the visual back charging signal and the coverage area of the first infrared signal.

[0051] The first preset position can be a fixed position point set in advance, or a position point dynamically calculated based on the charging station position and the current position of the mobile robot. By flexibly setting the first preset position, the mobile robot can more efficiently perform the rotating action and obtain the charging information during the return to the charging station.

[0052] The first position is a position point obtained by further narrowing the first preset position to the central axis of the charging station and a preset distance from the charging station. By narrowing the range of the first preset position, the accuracy and efficiency of the mobile robot in detecting the charging information when performing the rotating action are improved, and the return charging process is further optimized.

[0053] Step S2: control the mobile robot to rotate at the first preset position, and determine whether the mobile robot can obtain the first charging signal.

[0054] The first charging signal can be a visual charging signal (the coverage area of the visual charging signal is area 3 shown in FIG. 1), which can include feature information of the charging station, or feature information of a feature marker arranged on the charging station. As described above, the visual charging signal can be obtained by the vision sensor of the mobile robot. Specifically, the image captured by the vision sensor can be analyzed by color recognition, shape matching, edge detection, etc. to extract information related to the features of the charging station. By comparing the color, shape, size, etc. attributes, the extracted features are matched with the preset charging station features. If the matching is successful, it means that the vision sensor has obtained the feature information of the charging station. If the matching is not successful, it means that the vision sensor has not obtained the feature information of the charging station. At the same time, it can also be verified by actual verification to confirm whether the acquisition result of the vision sensor is accurate. For example, it can be manually checked whether the charging station really exists, or cross-verified by other sensors.

[0055] After reaching the first preset position, the advancing direction of the mobile robot may not be towards the charging station, and the field of view angle of the vision sensor of the mobile robot is limited. Therefore, even if the charging station is in front of the mobile robot, the mobile robot cannot obtain the effective first charging signal. Therefore, the robot needs to be controlled to rotate to try to obtain the first charging signal. During the rotation of the robot, the collected environmental information needs to be analyzed in real time, and the environmental information represents the feature information of the charging station.

[0056] Since the mobile robot can encounter various environmental changes during movement, such as obstacles, changes in illumination, failure of a vision sensor, etc., it is possible that the first return charging signal cannot be acquired at the first preset position. Therefore, in this step, when moving to the first preset position, it is determined whether the first return charging signal is acquired, i.e., whether the feature information of the charging station is detected. If the first return charging signal is not acquired, the process jumps to step S3, and if the first return charging signal is acquired, the process jumps to step S4.

[0057] Step S3: If the mobile robot cannot acquire the first return charging signal, it is determined whether the mobile robot can acquire the second return charging signal.

[0058] The second return charging signal can include an infrared signal (the coverage area of the infrared signal is area 1 and area 2 shown in FIG. 1, wherein if the infrared signal is a first infrared signal, the coverage area thereof is area 1 shown in FIG. 1, and if the infrared return charging signal is a second infrared signal, the coverage area thereof is area 2 shown in FIG. 1, the relationship between area 1, area 2, and area 3 is shown in FIG. 1 and described above, and will not be described again here). As described above, the infrared signal is emitted by the charging station, and thus can guide the mobile robot to return to charging. In this step, if the first return charging signal cannot be acquired, it is determined whether other return charging signals, such as the second return charging signal, can be acquired. If the second return charging signal can be acquired, the process jumps to step S5. If the second return charging signal cannot be acquired, the process jumps to step S6.

[0059] Step S4: If the mobile robot can acquire the first return charging signal, the mobile robot is guided to return to charging according to the first return charging signal.

[0060] Step S5: If the mobile robot can acquire the second return charging signal, the mobile robot is guided to return to charging according to the second return charging signal.

[0061] Specifically, the direction of the second return charging signal (i.e., the infrared signal) can be acquired first, then the mobile robot is controlled to rotate to the direction, and the mobile robot is controlled to move in the direction, so as to guide the mobile robot to move towards the charging station.

[0062] Step S6: If the mobile robot cannot acquire the second return charging signal at the first preset position, the mobile robot is controlled to move to a second preset position, and the first return charging signal and / or the second return charging signal is continued to be acquired.

[0063] Specifically, the mobile robot is controlled to rotate at the second preset position, and it is determined whether the first return charging signal and / or the second return charging signal is acquired; if the first return charging signal and / or the second return charging signal is acquired, the mobile robot is guided to return charging according to the first return charging signal and / or the second return charging signal. Since the mobile robot may encounter various environmental changes such as obstacles and illumination changes during movement, the positioning of the mobile robot is affected, and accumulated positioning errors are generated. Therefore, the "first preset position" to which the mobile robot moves according to the preset rule may not be the actual first preset position. At this time, the mobile robot may not be able to detect the first return charging signal and the second return charging signal, and thus the return charging cannot be implemented. Therefore, in this step, when the first return charging signal and the second return charging signal cannot be acquired after moving to the first preset position, the mobile robot is controlled to move to the second preset position to attempt to acquire the first return charging signal and / or the second return charging signal at another position, thereby increasing the probability of acquiring the two return charging signals and thus increasing the success rate of return charging.

[0064] Therefore, in the case that the mobile robot of the present application cannot acquire the first return charging signal for return charging at the first preset position, it is determined whether the second return charging signal is acquired. If the second return charging signal is acquired, the mobile robot is guided to return charging according to the second return charging signal, which is not limited to the first return charging signal guiding the mobile robot to return charging. Different return charging signals can be selected to guide the mobile robot to return charging. The technical problem of how to accurately find the charging station and successfully return charging in a complex environment when the mobile robot needs to return charging is solved, and the success rate and efficiency of return charging are improved.

[0065] In the foregoing introduction, the first return charging signal is a visual return charging signal, and the second return charging signal is an infrared signal. In another embodiment, the first return charging signal is an infrared signal, and the second return charging signal is a visual return charging signal. Therefore, the following two cases exist:

[0066] The first case: the first return charging signal is an infrared signal, and the second return charging signal is a visual signal. When the mobile robot rotates at the first preset position, it can first determine whether the infrared signal can be detected. If the infrared signal cannot be detected, it can be further determined whether the visual return charging signal is acquired. If the visual return charging signal is acquired, it means that the return charging signal is acquired, and the mobile robot is guided to return charging based on the visual return charging signal.

[0067] The second case: the first return charging signal is a visual signal, and the second return charging signal is an infrared signal. When the mobile robot rotates at the first preset position, it can first determine whether the visual return charging signal can be detected. If the visual return charging signal cannot be detected, it can be further determined whether the infrared signal can be acquired. If the infrared signal can be acquired, it also means that the return charging signal is acquired, and the mobile robot is guided to return charging based on the infrared signal.

[0068] Referring to FIG. 7, FIG. 7 is a flowchart of a method for controlling a mobile robot to return to a charging station according to an embodiment of the present application. As shown in FIG. 7, the step of determining whether the mobile robot meets the predetermined movement condition in step S1 can include the following steps.

[0069] Step S11: Determine whether the mobile robot leaves the charging station actively.

[0070] Active leaving of the charging station refers to the mobile robot leaving the charging station actively due to performing a cleaning, patrol, or other task. Passive leaving of the charging station refers to the mobile robot leaving the charging station accidentally due to an external factor (e.g., human movement, collision, etc.).

[0071] Specifically, it can be determined whether at least one of the following conditions exists: the angle value of the IMU sensor of the mobile robot is less than a predetermined angle value, and / or the ground clearance sensor is not activated, and there is a last stop point, a received work instruction, and an uncompleted task. If so, it is determined that the mobile robot leaves the charging station actively, and if not, it is determined that the mobile robot leaves the charging station passively.

[0072] If the angle of the IMU sensor changes too much, is greater than or equal to a predetermined angle value, or the ground clearance sensor is activated, it means that the mobile robot can be moved, resulting in a large tilt angle and ground clearance.

[0073] When the mobile robot actively stops, a stop point is recorded on the path of the stop, which is usually near the charging station. If the stop point does not exist, it means that the mobile robot is not actively stopped, for example, it can be passively stopped due to being moved by a person from the charging station.

[0074] If the mobile robot does not receive a work instruction and suddenly stops charging and stops, it can be determined that the mobile robot leaves the charging station passively.

[0075] If there is no work task, i.e., all work tasks have been completed, and the mobile robot leaves the charging station, it can be determined that the mobile robot leaves the charging station passively.

[0076] If there is a communication connection between the charging station and the mobile robot, the communication log or signal record can be analyzed. If an abnormal signal or communication interruption is found, it can be determined that the mobile robot leaves the charging station passively.

[0077] Therefore, the above different conditions can be used to determine whether the mobile robot leaves the charging station actively or passively. By considering different conditions comprehensively, the accuracy of determining the way the mobile robot leaves the charging station can be improved.

[0078] Step S12: If the mobile robot leaves the charging station actively, a step of controlling the mobile robot to move to a first predetermined position is performed.

[0079] If the mobile robot leaves the charging station actively, it means that it leaves the charging station to perform a task or the like, there is a normal moving path, that is, the positioning of the mobile robot is relatively accurate, and then the mobile robot can autonomously navigate to the first preset position according to a path planning algorithm.

[0080] Step S13: If the mobile robot leaves the charging station passively, the mobile robot is controlled to rotate at the current position to obtain the first charging back signal or / and the second charging back signal.

[0081] If it is judged that the mobile robot leaves the charging station passively, it means that the current positioning accuracy of the mobile robot is low, and then the mobile robot can be controlled to perform a rotating action at the current position. Through rotation, the mobile robot can obtain the surrounding environment information to obtain the charging station information, that is, to obtain the first charging back signal and / or the second charging back signal, and then reposition and move according to the obtained charging back signal.

[0082] It is worth noting that if the mobile robot leaves the charging station passively and is moved to another area that is not connected to the charging station, it is directly judged as a situation that cannot be charged back, and the mobile robot does not need to perform a rotating action, but directly reports an error. Avoiding the robot to perform invalid operation in the situation that cannot be charged back, and timely informing the user to intervene. And after reporting an error and stopping, the mobile robot is in a dormant state, and a message or / and a voice prompt is sent to the user to indicate that the charging back fails.

[0083] The embodiment executes different charging back strategies based on whether the mobile robot leaves the charging station actively or passively. When the mobile robot leaves the charging station actively, the robot is controlled to move to the first preset position; and when the robot leaves the charging station passively, the robot is controlled to rotate at the current position to ensure that the signal for charging back can be received. The method solves the problem of how the mobile robot effectively charges back in different leaving states. For the case of actively leaving the charging station, it is ensured that the robot can accurately return to the charging position; and for the case of passively leaving, the position is adjusted through rotation to receive the charging back signal. Through the above control strategy, the charging back efficiency and accuracy of the mobile robot can be improved, the energy waste caused by charging back failure can be reduced, the autonomous operation ability of the robot can be improved, and it is ensured that the robot can successfully charge back in various situations, thereby prolonging the working time and improving the work efficiency.

[0084] In one embodiment, the specific method of controlling the mobile robot to move to the first preset position in step S1 can be to plan a navigation path for the mobile robot, and the navigation path can specifically include the following:

[0085] The first kind: obtaining the coordinates of the current position of the mobile robot and the coordinates of the first preset position, planning a shortest path from the current position to the first preset position, judging whether there is an obstacle on the shortest path, if there is an obstacle, generating a planning path to avoid the obstacle;

[0086] The second kind: based on the historical map, obtaining a satellite signal map of the working area, and obtaining a region where the intensity of the satellite signal is greater than a preset value, and planning a navigation path into the region where the intensity of the satellite signal is greater than the preset value;

[0087] The third kind: planning a path to avoid direct sunlight of the visual sensor. Specifically, if the direction of sunlight is perpendicular to the optical window of the sensor, it is considered that the sunlight directly strikes the visual sensor, and at this time, the planned path is required to be as possible as to form an angle greater than 30 degrees with the direction of sunlight, so as to avoid the sunlight from interfering with the visual sensor.

[0088] Different navigation paths can be planned according to different situations, for example, if it is noon with sufficient sunlight, the navigation path can be planned in the first kind or the second kind to avoid the influence of sunlight, if the working area is in a remote place and the intensity of satellite signal is weak, the navigation path can be planned in the first kind or the third kind to avoid the influence of satellite signal, and so on. Thus, the planned navigation path can be more in line with the current moving conditions.

[0089] After the navigation path is planned, the mobile robot moves to the first preset position according to the navigation path. Specifically, the environment information obtained by the satellite positioning device and the visual sensor can be used for positioning, and the mobile robot is controlled to move along the navigation path to the first preset position according to the positioning information. In the area where the quality of satellite signal is good, only the satellite positioning device can be used for positioning, in the area where the quality of satellite signal is not good, the visual sensor or the visual sensor and the satellite positioning device can be used for positioning, or only the visual sensor can be used for positioning. The robot is controlled to move along the navigation path through the positioning information of the robot. Therefore, the movement of the mobile robot can be positioned in real time through the positioning device, and the mobile robot moves combined with the real-time positioning information and the navigation path, which can avoid temporary obstacles and the like, thereby ensuring that the mobile robot can move smoothly.

[0090] In an embodiment, if the mobile robot is actively leaving the charging station, and the first return charging signal and the second return charging signal are not acquired at the first preset position, the mobile robot is controlled to move to the second preset position to continue acquiring the first return charging signal and / or the second return charging signal at the second preset position, i.e., step S6 is performed. However, before the mobile robot moves to the second preset position, the number of times of movement of the mobile robot can be further determined. For details, refer to FIG. 8, which is a flowchart of a return charging control method of a mobile robot according to an embodiment of the present application. As shown in FIG. 8, the method can include the following steps:

[0091] Step S21: Determine whether the number of times of movement of the mobile robot is less than a preset number of times.

[0092] Step S22: If the number of times of movement is less than the preset number of times, perform a step of controlling the mobile robot to move to the second preset position.

[0093] Step S23: If the number of times of movement is greater than or equal to the preset number of times, control the mobile robot to stop moving.

[0094] In an embodiment, the preset number of times is not greater than 3. Since the reasons for failure of the mobile robot to acquire the first return charging signal and the second return charging signal are complex, it is not possible to determine whether the problem is with the vision sensor of the mobile robot itself or with the surrounding environment. If the problem is with the surrounding environment, the mobile robot can avoid the interference by moving. If the problem is with the vision sensor of the mobile robot itself, the mobile robot cannot acquire the first return charging signal and the second return charging signal by changing the position. Therefore, after multiple movements still fail to acquire the first return charging signal and the second return charging signal, the mobile robot stops moving, and the mobile robot is in a dormant state. The mobile robot sends a message and / or a voice prompt to the user to indicate that the return charging has failed. In this embodiment, by setting a preset number of times, the system can determine whether to continue moving the mobile robot or stop moving the mobile robot according to the number of times of movement, thereby solving the problem of how to effectively control the mobile robot to stop moving after completing a task, avoiding waste of resources and reduction of efficiency, effectively saving energy, and improving work efficiency.

[0095] The second preset position is set in the same way as the first preset position, i.e., at a position where the mobile robot can be successfully returned to the charging station. Specifically, the first preset position and the second preset position can satisfy the following relationship:

[0096] AB = BC and AB is perpendicular to BC,

[0097] A is the position coordinate of the center of the wheel shaft of the mobile robot when the mobile robot is docked on the charging station, B is the coordinate of the first preset position, and C is the coordinate of the second preset position.

[0098] That is, the first preset position and the second preset position are equidistant from the charging station, and the second preset position is one of the two positions on the two sides of the first preset position relative to the charging station, and the two lines of the first preset position and the second preset position are perpendicular to the line connecting the first preset position and the charging station. The coverage area of the visual charging back signal is collected, and in a normal case, the first preset position and the second preset position can both obtain the visual charging back signal (i.e., the first charging back signal) through the visual sensor. By defining the geometric relationship (isosceles right triangle) between the second preset position and the first preset position (i.e., the position of the mobile robot wheel center on the charging station), it is ensured that the mobile robot can face the charging station at a suitable angle and distance when moving to the second preset position, solving the problem of how to accurately control the mobile robot to reach a position that is conducive to charging back, improving the accuracy and success rate of the mobile robot charging back, and reducing the charging back failure caused by improper position.

[0099] If the first charging back signal and / or the second charging back signal is not obtained at the second preset position (e.g., position C in FIG. 1), the mobile robot is controlled to move from the second preset position to a third preset position (e.g., position D in FIG. 1), and the mobile robot is controlled to rotate at the third preset position to obtain the first charging back signal and / or the second charging back signal, wherein the third preset position and the second preset position are symmetrically arranged on the two sides of the first preset position (e.g., position B in FIG. 1). That is, if the first charging back signal and the second charging back signal are not obtained on one side of the first preset position, the mobile robot is controlled to move to the other side of the first preset position to continue to obtain the first charging back signal and / or the second charging back signal. In this way, the first charging back signal and the second charging back signal are continuously attempted to be obtained at other preset positions, thereby improving the probability of obtaining the first charging back signal and the second charging back signal. The second preset position and the third preset position are symmetrically arranged relative to the first preset position, which can ensure that the field of view of the mobile robot at the two positions is the same, and the difficulty of obtaining the first charging back signal and the second charging back signal is equivalent.

[0100] Referring to FIG. 9, FIG. 9 is a flowchart of another method for controlling the charging back of a mobile robot according to an embodiment of the present application. As shown in FIG. 9, in an embodiment, if the second charging back signal is obtained at the first preset position or the second preset position in step S3 or S6, the mobile robot is guided to charge back according to the second charging back signal, which can include the following steps:

[0101] Step S31: Determine whether the second charging back signal is the first infrared signal.

[0102] As described above, the first infrared signal is radiated at a long distance, such as the area 1 shown in FIG. 1. If it is the first infrared signal, go to step S32, and if it is the second infrared signal, i.e., radiated at a short distance (such as the area 2 shown in FIG. 1), go to step S33.

[0103] Step S32: If the first infrared signal is received, the mobile robot is guided to move according to the first infrared signal, and it is determined whether the first return charging signal and / or the third return charging signal is acquired.

[0104] Since the first infrared signal is emitted from a long distance, the current position of the mobile robot may not be able to acquire the visual return charging signal, and thus the mobile robot is guided to move according to the first infrared signal, and it is determined whether the first return charging signal and / or the third return charging signal is acquired during the movement, wherein the third return charging signal is a magnetic field signal emitted by the guide wire of the charging station.

[0105] If the first return charging signal and / or the third return charging signal is acquired, the process jumps to step S34, and if the first return charging signal and / or the third return charging signal is not acquired, the process jumps to step S35.

[0106] Step S33: If the second infrared signal is received, the first return charging signal and / or the third return charging signal is acquired at the current position, and the mobile robot is guided to continue the return charging according to the first return charging signal and / or the third return charging signal.

[0107] As shown in FIG. 1, the area covered by the second infrared signal is in the area covered by the first return charging signal, and thus if the second infrared signal is acquired, it indicates that the mobile robot is currently in the area covered by the first return charging signal (i.e., the visual return charging signal), and thus the first return charging signal can be acquired. Further, if the mobile robot is currently in the range of the magnetic field generated by the guide wire of the charging station due to the electric conduction, the third return charging signal can be further acquired. The mobile robot can be guided to continue the return charging according to the acquired first return charging signal and / or the third return charging signal.

[0108] Step S34: If the first return charging signal and / or the third return charging signal is acquired, the mobile robot is guided to continue the return charging according to the first return charging signal and / or the third return charging signal, and the coverage area of the visual return charging signal and the coverage area of the magnetic field signal have an intersection.

[0109] Step S35: An alarm is prompted.

[0110] In the embodiment, the second recharge signal is further divided into a first infrared signal and a second infrared signal, wherein the coverage area of the second infrared signal is located in the intersection of the coverage areas of the first infrared signal and the visual recharge signal. If the mobile robot acquires the first infrared signal, the mobile robot is guided to move into the coverage area of the visual signal according to the first infrared signal, so as to acquire the visual recharge signal. If the mobile robot acquires the second infrared signal, the mobile robot stops moving and acquires the visual recharge signal at the current position. The embodiment solves the positioning error problem caused by signal interference when the mobile robot approaches the recharge position. By refining the coverage range of the infrared signal and combining the visual signal for accurate positioning, the positioning accuracy and stability of the mobile robot during the recharge process are further improved, and the smooth progress of the recharge process is ensured.

[0111] In an embodiment, as described above and shown in FIGS. 2 and 3, the mobile robot comprises a first visual sensor, a second visual sensor and a third visual sensor, wherein the first visual sensor and the third visual sensor are arranged on the two sides, and the second visual sensor is arranged in front of the mobile robot, and the first visual sensor, the second visual sensor and the third visual sensor are used to acquire the first recharge signal. If only the third recharge signal is detected in steps S33 and S34, the mobile robot is controlled to rotate, and the first recharge signal is acquired by using the second visual sensor and the third sensor. Since the third recharge signal is acquired, it indicates that the mobile robot has been located near the charging station. Under normal circumstances, the visual sensor can acquire the first recharge signal (i.e. the charging station information of the charging station). If the first recharge signal cannot be acquired at this time, it indicates that the second visual sensor facing the charging station is at least partially damaged or blocked, or the optical window thereof is contaminated, and at this time the mobile robot needs to be controlled to rotate to acquire the first recharge signal by using other visual sensors. For example, if one of the binocular cameras of the second visual sensor cannot detect the first recharge signal, the mobile robot is rotated to face the charging station in the direction of the other binocular camera of the second visual sensor, so as to acquire the first recharge signal. For another example, if the second visual sensor cannot acquire the first recharge signal, the second sensor and the third sensor on the side are turned to face the charging station, so as to acquire the first recharge signal. The success rate of acquiring the first recharge signal can be improved. If all the visual sensors cannot acquire the first recharge signal, the mobile robot is stopped and an error is reported.

[0112] In an embodiment, if the first recharge signal and / or the third recharge signal is acquired, the mobile robot can be guided to recharge according to the first recharge signal and / or the third recharge signal, which can include one of the following schemes:

[0113] The first scheme: a recharge path is planned by using the first recharge signal, and the mobile robot is guided to recharge according to the recharge path.

[0114] Specifically, the mobile robot first pre-processes the image data of the acquired visual return charging signal (i.e., the first return charging signal), and then uses image processing techniques and computer vision algorithms (such as edge detection, color segmentation, shape matching, etc.) to identify the boundaries of the work area, obstacles (such as trees, rocks, etc.), and the location of the charging base station. By analyzing the feature information in the image, the relative positional relationship between the mobile robot and the charging base station is determined. Further, based on the results of image recognition and target detection, a path planning algorithm (such as A* algorithm, genetic algorithm, etc.) is used to generate an optimal path for the mobile robot from the current position to the charging base station. Considering the shape, size of the work area and the distribution of obstacles, the path planning algorithm will try to shorten the path length, reduce the travel time, and avoid collision with obstacles.

[0115] During the return charging process, various sensors such as inertial measurement units (IMU) and global navigation satellite systems (GNSS) can be further combined to realize real-time positioning of the mobile robot.

[0116] In this scheme, the return charging path can be planned by acquiring a visual return charging signal, and the navigation guidance for the mobile robot can be provided by combining the path planning results, ensuring that it can accurately travel to the charging base station according to the planned path, without the need to acquire visual return charging signals in real time, reducing the computing power of the mobile robot, thereby saving the cost of computing power.

[0117] The second scheme: in the process of controlling the mobile robot to return charge, the first return charging signal is acquired in real time, and the mobile robot is guided according to the first return charging signal.

[0118] In this scheme, in the process of controlling the mobile robot to return charge, the first return charging signal is acquired in real time, and the moving direction of the mobile robot is adjusted in real time according to the first return charging signal, so as to avoid the mobile robot from colliding with obstacles, especially temporary obstacles, and to ensure the safety of the mobile robot.

[0119] The third scheme: based on the first return charging signal, the mobile robot is controlled to move until the third return charging signal is detected, and then the mobile robot is guided according to the third return charging signal, the third return charging signal is the magnetic field signal emitted by the guide wire of the charging station, and the coverage area of the visual return charging signal and the coverage area of the magnetic field signal exist intersection.

[0120] In the scheme, the visual charging signal (i.e., the first charging signal) and the magnetic field signal (i.e., the third charging signal) are combined to control the mobile robot charging. The magnetic field signal is emitted by the guide wire of the charging station, and the visual sensor can only obtain part of the feature information of the charging station due to the field of view angle, which cannot fully reflect the characteristics of the charging station. In this case, combining the magnetic field signal to detect and locate the charging station can improve the accuracy of positioning and the success rate of charging.

[0121] By using multiple types of charging signals (including visual charging signals and magnetic field signals) to guide the mobile robot charging, the problem of how to effectively guide the mobile robot charging under different conditions (such as insufficient light and blocked view) is solved, and the adaptability and robustness of the mobile robot charging are improved, ensuring successful charging in various environments.

[0122] The above several schemes for guiding the mobile robot charging according to the first charging signal have different effects, and in actual application, the appropriate charging scheme can be selected according to the actual situation, and the present application does not limit it.

[0123] As described above, the mobile robot includes two symmetrically arranged magnetic induction sensors (including a first magnetic induction sensor and a second magnetic induction sensor), which are used to obtain the magnetic field signal. In the third scheme described above, the visual charging signal and the magnetic field signal are combined to control the mobile robot charging, which can be further specified as follows: according to the first charging signal, the mobile robot is controlled to move until both magnetic induction sensors of the mobile robot detect the magnetic field signal, and then the mobile robot is guided to charge according to the magnetic field signal. In this way, when the mobile robot is far away from the charging station, the first charging signal is used to guide the mobile robot to move towards the charging station, and when the mobile robot is close to the charging station, the symmetrically arranged two magnetic induction sensors are used to detect the magnetic field signal emitted by the charging station. When both sensors detect the magnetic field signal, it means that the mobile robot has arrived near the charging station, and then the charging is guided according to the magnetic field signal, solving the problem of how to more accurately determine whether the mobile robot has arrived at the accurate position of the charging station, reducing the charging failure caused by position deviation, and further improving the accuracy and stability of the mobile robot charging.

[0124] Specifically, when guiding the mobile robot back to charge according to the magnetic field signal, the pose of the mobile robot can be adjusted so that the difference between the signal strengths of the two magnetic induction sensors is within a preset range. That is, if the absolute value of the difference between the third back charging signal detected by the first magnetic induction sensor and the third back charging signal detected by the second magnetic induction sensor is greater than a preset value, the mobile robot is controlled to adjust the moving direction; if the absolute value of the difference between the third back charging signal detected by the first magnetic induction sensor and the third back charging signal detected by the second magnetic induction sensor is less than or equal to the preset value, the mobile robot does not need to be controlled to adjust the moving direction. Because the two magnetic induction sensors are symmetrically arranged with respect to the center axis of the mobile robot, when the strengths of the magnetic field signals detected by the two magnetic induction sensors are equal, the alignment of the mobile robot and the charging station can be ensured. By detecting the magnetic field signal through the magnetic induction sensor, adjusting the pose of the mobile robot, and ensuring that the difference between the signal strengths of the two magnetic induction sensors is within a preset range, the problem that the mobile robot cannot be smoothly docked with the charging station due to inaccurate pose during magnetic field guided back charging is solved. By adjusting the pose, it is ensured that the mobile robot can accurately align with the charging station, thereby improving the back charging success rate.

[0125] It is worth noting that in the three schemes for guiding the mobile robot back to charge according to the first back charging signal introduced above, regardless of which scheme is adopted, the offset amount of the mobile robot can be obtained according to the first back charging signal, and the mobile robot is guided back to charge according to the offset amount. The offset amount includes an offset distance and an offset angle. By obtaining the offset amount (including the offset distance and the offset angle) between the mobile robot and the charging station through the first back charging signal (such as the visual back charging signal), and then guiding the mobile robot back to charge accordingly, the problem that the mobile robot cannot accurately dock with the charging station due to position or direction deviation during visual guided back charging is solved. By accurately calculating the offset amount and adjusting the position and direction of the mobile robot accordingly, more accurate back charging docking can be achieved, thereby improving the back charging success rate.

[0126] A further scheme for guiding the mobile robot back to charge according to the offset amount can be as shown in FIG. 10, including the following steps:

[0127] Step S41: determining the center axis of the charging station;

[0128] Step S42: determining the offset distance according to the current position of the mobile robot and the center axis, and determining the offset angle according to the current direction of the mobile robot and the vertical direction of the entrance of the charging station.

[0129] Step S43: controlling the mobile robot to move to the center axis of the charging station and align along the center axis according to the offset distance and the offset angle.

[0130] Specifically, when the charging connector of the mobile robot is docked with the charging pad of the charging station, the mobile robot is controlled to continue moving for a preset time and / or a preset distance and then stop moving. Because the charging connector and the charging pad are docked, the mobile robot can recognize that the charging station enters a charging state, but the charging connector is not in a stable electrical connection state, so the mobile robot needs to be controlled to continue moving to make the charging connector and the charging pad in close contact, increase the stability of the connection between the two, and thus improve the stability of the charging.

[0131] The embodiment first determines the offset distance and the offset angle between the mobile robot and the charging station, then guides the robot to move onto the center axis of the charging station according to the offset angle and the offset distance, and then piles up along the center axis, so that the mobile robot adjusts the posture of piling up on the center axis. The scheme further refines the acquisition of the offset and the recharging guidance process, including determining the center axis of the charging station, calculating the offset distance and the offset angle, and controlling the mobile robot to move onto the center axis of the charging station and pile up, solving the problem that the mobile robot may fail to recharge due to inaccurate judgment of the offset in the recharging process. Through accurate offset calculation and recharging guidance, it is ensured that the mobile robot can accurately dock with the charging station, and the recharging efficiency and success rate are improved.

[0132] It is worth noting that in the above description of the present application, all the schemes of controlling the mobile robot to rotate can be specifically: controlling the mobile robot to rotate according to a preset direction and angle, and stopping rotating if the first recharging information meeting the condition is obtained during the rotation. For example, the mobile robot can be controlled to rotate in a clockwise or counterclockwise direction, and if complete feature information of the charging station is obtained during the rotation, it can be considered that the first recharging information meeting the condition is obtained, and then the rotation is stopped. This scheme describes that in the process of controlling the mobile robot to rotate, the mobile robot rotates according to a preset direction and angle, and continuously detects whether the first recharging information meeting the condition is obtained during the rotation, and stops rotating immediately when the information meeting the condition is detected, solving the problem that the mobile robot blindly rotates when searching for a recharging point, resulting in low efficiency and waste of energy. By rotating according to a preset direction and angle and stopping when valid recharging information is detected, the efficiency and accuracy of searching for a recharging point are improved, the precise control and efficient operation of the mobile robot when searching for a recharging point are realized, unnecessary rotation and energy consumption are reduced, and the overall work efficiency is improved.

[0133] Further, before controlling the mobile robot to rotate, if the mobile robot detects at least part of the charging station in the visual back charging signal, the mobile robot is controlled to rotate according to the position of the charging station in the field of view of the mobile robot, so that the charging station is located in the center of the field of view. Before rotation, the information of the detected part of the charging station is determined to control the rotation of the mobile robot, which can further accurately control the direction of the rotation of the mobile robot, avoid unnecessary rotation and energy consumption, and improve the overall work efficiency.

[0134] Further, before controlling the mobile robot to rotate, it can be determined whether the rotation of the mobile robot is limited due to environmental obstacles, for example, whether there are obstacles around the mobile robot. If the rotation of the mobile robot is blocked (for example, there are obstacles), the mobile robot is controlled to move to a position where it can freely rotate in an open area before performing the rotation action. This avoids the mobile robot performing the rotation action in a limited position, which prevents the mobile robot from obtaining back charging information, and ensures that the mobile robot can successfully complete the back charging process.

[0135] Further, before controlling the mobile robot to rotate, if the mobile robot can detect at least one of the visual back charging signal, the infrared signal or the magnetic field signal, the mobile robot directly uses these signals for back charging without performing the rotation action. This reduces unnecessary rotation actions and improves the efficiency and response speed of the mobile robot back charging.

[0136] First, the mobile robot can be controlled to rotate in place, i.e., to rotate with the center of the mobile robot as the rotation center. If the first back charging information is not obtained after rotating in place, the radius of the rotation is expanded, and the mobile robot is controlled to rotate with the expanded radius. By dynamically adjusting the rotation radius, the mobile robot can search for a back charging point in a wider range, solving the problem that the mobile robot may miss a back charging point due to a limited rotation range when rotating in place, and improving the coverage and success rate of the search.

[0137] Alternatively, different rotation center positions can be set according to the way the mobile robot leaves the charging station. If the mobile robot actively leaves the charging station, the rotation center is located inside the body, i.e., the mobile robot rotates with the center of the mobile robot as the rotation center. If the mobile robot is passive to leave the charging station, the rotation center is located outside the body, i.e., the radius of the rotation is expanded, and the mobile robot is controlled to rotate with the expanded radius. By reasonably setting the rotation center, the mobile robot can more effectively detect visual back charging information when performing the rotation action, and improve the success rate of back charging.

[0138] In the solution of expanding the radius of rotation, more specifically, the mobile robot can be controlled to rotate in a spiral manner, or to rotate with a specific position on the extension line of the wheel shafts of the two wheels of the mobile robot as the center. By further refining the rotation mode after expanding the radius of rotation (including rotating in a spiral manner or rotating with a specific position as the center), the mobile robot can more efficiently cover the possible recharging point area while expanding the search range, solving the problem of how to more efficiently rotate to find the recharging point after expanding the radius of rotation, and improving the speed and accuracy of finding the recharging point.

[0139] In addition, the speed of the mobile robot rotating at the plurality of preset positions is less than the speed of the mobile robot rotating when avoiding obstacles. For example, the speed of rotating at the first preset position or the second preset position or the fourth preset position is less than the speed of the mobile robot rotating when avoiding obstacles. When the mobile robot approaches the charging station for recharging, the rotation speed of the mobile robot at a specific preset position (such as the first preset position or the second preset position) is lower than the rotation speed when avoiding obstacles, solving the problem that the mobile robot may not be accurately docked or collide with the charging station due to the too fast rotation speed. By reducing the rotation speed, the mobile robot is more stable and accurate when docking the charging station during recharging, improving the success rate of recharging.

[0140] The embodiments of the present application also provide a recharging control system of a mobile robot, which is applied to the recharging control method described above. Please refer to FIG. 11, the recharging control system 100 of the mobile robot comprises:

[0141] The moving module 101 is configured to control the mobile robot to move to the first preset position when the mobile robot needs to be recharged, under the condition that a preset moving condition is met.

[0142] The preset condition is to determine whether the mobile robot is actively leaving the charging station. If the mobile robot is actively leaving the charging station, the preset moving condition is met, and the mobile robot is controlled to move to the first preset position. If the mobile robot is passively leaving the charging station, the preset moving condition is not met, and the mobile robot is controlled to rotate at the current position without moving to the first preset position. The specific determination process is as described above and will not be repeated here.

[0143] The rotating module 102 is configured to control the mobile robot to rotate at the first preset position.

[0144] The specific rotating method is as described above and will not be repeated here.

[0145] The first determining module 103 is configured to determine whether the mobile robot can obtain a first recharging signal.

[0146] If the first return charging signal is acquired, the mobile robot is guided to return to charging according to the first return charging signal, and the specific return charging process is as described above and will not be repeated here.

[0147] The second determining module 104 is configured to determine whether the mobile robot can acquire the second return charging signal when the first determining module determines that the mobile robot cannot acquire the first return charging signal.

[0148] If the second return charging signal cannot be acquired, the mobile robot can be controlled to move to the second preset position to acquire the first return charging signal and / or the second return charging signal in the case that the mobile robot actively leaves the charging station, and the specific scheme is as described above and will not be repeated here.

[0149] The return charging module 105 is configured to guide the mobile robot to return to charging according to the second return charging signal when the mobile robot can acquire the second return charging signal.

[0150] The specific scheme of guiding the mobile robot to return to charging according to the second return charging signal is as described above and will not be repeated here.

[0151] It should be understood that the return charging control system 100 of the embodiment can perform all the return charging control methods of the mobile robot as described above and will not be repeated here.

[0152] To solve the above technical problems, the embodiment of the present application further provides a computer device. For details, please refer to FIG. 12, which is a basic structure block diagram of the computer device of the embodiment.

[0153] The computer device 6 includes a memory 61, a processor 62, and a network interface 63 which are connected to each other through a system bus. It should be pointed out that only the computer device 6 with components 61-63 is shown in the figure, but it should be understood that it is not required to implement all the shown components, and more or fewer components can be alternatively implemented. Among them, those skilled in the art can understand that the computer device here is a device capable of automatically performing numerical calculation and / or information processing according to pre-set or stored instructions, and its hardware includes but is not limited to microprocessors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), embedded devices, etc.

[0154] The computer device can be a desktop computer, a notebook computer, a palm computer, a cloud server, or the like. The computer device can interact with a user through a keyboard, a mouse, a remote controller, a touchpad, a voice control device, or the like.

[0155] The memory 61 can include at least one type of readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory, or the like), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, or the like. In some embodiments, the memory 61 can be an internal storage unit of the computer device 6, such as a hard disk or a memory of the computer device 6. In other embodiments, the memory 61 can also be an external storage device of the computer device 6, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, or the like. Of course, the memory 61 can include both an internal storage unit and an external storage device of the computer device 6. In this embodiment, the memory 61 is generally used to store an operating system installed in the computer device 6, various information management operating systems, computer readable instructions of the mobile robot recharging control method, or the like. In addition, the memory 61 can also be used to temporarily store various data that has been output or will be output.

[0156] The processor 62 can be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip in some embodiments. The processor 62 is generally used to control the overall operation of the computer device 6. In this embodiment, the processor 62 is used to execute computer readable instructions or process data stored in the memory 61, such as computer readable instructions of the mobile robot recharging control method.

[0157] The network interface 63 can include a wireless network interface or a wired network interface, and is generally used to establish a communication connection between the computer device 6 and other electronic devices.

[0158] The present application also provides another embodiment, i.e., a computer program product storing computer readable instructions executable by at least one processor to cause the at least one processor to perform the steps of the mobile robot recharging control method as described above.

[0159] The embodiment of the application introduces a mobile robot back charging control method and system, including the following steps: when the mobile robot needs to be back charged, if the preset movement condition is met, the mobile robot is controlled to move to a first preset position; the mobile robot is controlled to rotate at the first preset position, and it is judged whether the mobile robot can obtain a first back charging signal; if the mobile robot cannot obtain the first back charging signal, it is judged whether the mobile robot can obtain a second back charging signal; if the mobile robot can obtain the second back charging signal, the mobile robot is guided to back charge according to the second back charging signal. Thus, when the mobile robot cannot obtain the first back charging signal at the first preset position, the mobile robot can be guided to back charge through other back charging signals, such as the second back charging signal, and the mobile robot can be guided to back charge through different back charging signals, thereby improving the success rate of the mobile robot back charging.

[0160] Through the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment method can be realized by means of software and the necessary general hardware platform, of course, it can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a plurality of instructions for making a terminal device (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) execute the method described in each embodiment of the present application.

[0161] The technical features of the above embodiments can be combined in any way. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0162] The above embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method of return charging control of a mobile robot, wherein, The method comprises the following steps: When the mobile robot needs to be recharged, if a preset moving condition is met, the mobile robot is controlled to move to a first preset position; The mobile robot is controlled to rotate at the first preset position, and it is determined whether the mobile robot can obtain a first recharging signal; If the mobile robot cannot obtain the first recharging signal, it is determined whether the mobile robot can obtain a second recharging signal; If the mobile robot can obtain the second recharging signal, the mobile robot is guided to be recharged according to the second recharging signal.

2. The recharging control method of claim 1, wherein, The preset moving condition comprises: It is determined whether the mobile robot actively leaves the charging station; If the mobile robot actively leaves the charging station, the step of controlling the mobile robot to move to the first preset position is performed; If the mobile robot passively leaves the charging station, the mobile robot is controlled to rotate at the current position to obtain the first recharging signal or / and the second recharging signal.

3. The recharging control method of claim 2, wherein, The step of determining whether the mobile robot actively leaves the charging station further comprises: Whether at least one of the following conditions exists: The angle value of the IMU sensor of the mobile robot is less than a preset angle value, and / or the ground clearance sensor is not started, and there is a lower pile point, a received work instruction, and an unfinished task; If yes, it is determined that the mobile robot actively leaves the charging station; If no, it is determined that the mobile robot passively leaves the charging station.

4. The recharging control method of claim 1, wherein, The recharging control method further comprises: If the mobile robot fails to obtain the second recharging signal at the first preset position, the mobile robot is controlled to move to a second preset position; The mobile robot is controlled to rotate at the second preset position, and it is determined whether the first recharging signal and / or the second recharging signal is obtained; If the first recharging signal and / or the second recharging signal is obtained, the mobile robot is guided to be recharged according to the first recharging signal and / or the second recharging signal.

5. The recharging control method of claim 4, wherein, The step of controlling the mobile robot to rotate at the first preset position or at the second preset position further comprises: The mobile robot is controlled to rotate according to a preset direction and angle, and if a first recharging signal meeting the condition is obtained during the rotation, the rotation is stopped.

6. The recharging control method of claim 4, wherein, The first recharging signal is a visual recharging signal, and before the step of controlling the mobile robot to rotate at the first preset position or at the second preset position, the method comprises: If at least part of the charging station is detected in the visual recharging signal obtained by the mobile robot, the mobile robot is controlled to rotate according to the position of the charging station in the field of view of the mobile robot, so that the charging station is located at the center of the field of view.

7. The recharging control method of claim 4, wherein, Before the step of controlling the mobile robot to move to the second preset position, the method further comprises: It is determined whether the number of movements of the mobile robot is less than a preset number; If the number of movements is less than the preset number, the step of controlling the mobile robot to move to the second preset position is performed; If the number of movements is greater than or equal to the preset number, the mobile robot is controlled to stop moving.

8. The recharging control method of claim 4, wherein, The second preset position and the first preset position satisfy the following relationship: AB = BC and AB perpendicular to BC, wherein the A is a position coordinate of a wheel shaft center of the mobile robot when the mobile robot is parked on a charging station, the B is a coordinate of the first preset position, and the C is a coordinate of the second preset position.

9. The recharging control method of claim 8, wherein, The method further comprises: If the first return charging signal and / or the second return charging signal are not acquired at the second preset position, the mobile robot is controlled to move from the second preset position to a third preset position, and the mobile robot is controlled to rotate at the third preset position to acquire the first return charging signal and / or the second return charging signal, wherein the third preset position and the second preset position are symmetrically arranged on two sides of the first preset position.

10. The recharging control method of claim 2, wherein, The first return charging signal is a visual return charging signal, the second return charging signal is an infrared signal, the infrared signal includes a first infrared signal and a second infrared signal, the coverage area of the visual return charging signal and the coverage area of the first infrared signal have an intersection, and the coverage area of the second infrared signal is in the intersection; The step of guiding the mobile robot to return charge according to the second return charging signal further comprises: determining whether the second return charging signal is the first infrared signal; if the first infrared signal is determined, the mobile robot is controlled to move by using the first infrared signal, and it is determined whether the first return charging signal and / or a third return charging signal are acquired; if the first return charging signal and / or the third return charging signal are acquired, the mobile robot is guided to continue to return charge according to the first return charging signal and / or the third return charging signal, the third return charging signal is a magnetic field signal emitted by a guide wire of the charging station, and the coverage area of the visual return charging signal and the coverage area of the magnetic field signal have an intersection.

11. The recharging control method of claim 10, wherein, The step of guiding the mobile robot to return charge according to the first return charging signal and / or the third return charging signal further comprises: a return charging path is planned by using the first return charging signal, and the mobile robot is guided to return charge according to the return charging path; or in the process of controlling the mobile robot to return charge, the first return charging signal is acquired in real time, and the mobile robot is guided to return charge according to the first return charging signal; or based on the first return charging signal, the mobile robot is controlled to move until the third return charging signal is detected, and then the mobile robot is guided to return charge according to the third return charging signal.

12. The recharging control method of claim 11, wherein, The mobile robot comprises a first magnetic induction sensor and a second magnetic induction sensor which are symmetrically arranged, and the step of guiding the mobile robot to return charge according to the third return charging signal further comprises: if the absolute value of the difference between the third return charging signal detected by the first magnetic induction sensor and the third return charging signal detected by the second magnetic induction sensor is greater than a preset value, the mobile robot is controlled to adjust the moving direction. If the absolute value of the difference between the third charging signal detected by the first magnetic induction sensor and the third charging signal detected by the second magnetic induction sensor is less than or equal to the preset value, the mobile robot does not need to be controlled to adjust the moving direction.

13. The recharging control method of claim 11, wherein, The step of guiding the mobile robot to return to charging according to the first return charging signal further comprises: An offset of the mobile robot is obtained according to the first return charging signal, and the mobile robot is guided to return to charging according to the offset.

14. The recharging control method of claim 13, wherein, The offset comprises an offset distance and an offset angle. The step of obtaining the offset of the mobile robot according to the first return charging signal further comprises: A central axis of the charging station is determined. The offset distance is determined according to the current position of the mobile robot and the central axis, and the offset angle is determined according to the current direction of the mobile robot and the vertical direction of the charging station entrance. The step of guiding the mobile robot to return to charging according to the offset further comprises: The mobile robot is controlled to move to the central axis of the charging station and to align along the central axis according to the offset distance and the offset angle.

15. The recharging control method of claim 14, wherein, The step of aligning along the central axis further comprises: When the charging connector of the mobile robot is connected to the charging pad of the charging station, the mobile robot is controlled to continue moving for a preset time and / or a preset distance and then stop moving.

16. The recharging control method of claim 10, wherein, The mobile robot comprises a first visual sensor, a second visual sensor and a third visual sensor, wherein the first visual sensor and the third visual sensor are arranged on both sides, and the second visual sensor is arranged at the front of the mobile robot, and the first visual sensor, the second visual sensor and the third visual sensor are used to obtain the first return charging signal. The step of determining whether the first return charging signal and / or the third return charging signal is obtained further comprises: If only the third return charging signal is detected, the mobile robot is controlled to rotate, and the first return charging signal is obtained by using the second visual sensor and the third sensor.

17. The recharge control method of claim 1, wherein, The step of controlling the mobile robot to move to the first preset position further comprises: A navigation path is planned, comprising: The coordinates of the current position and the coordinates of the first preset position are obtained, a shortest path from the current position to the first preset position is planned, and it is determined whether there is an obstacle on the shortest path, if there is an obstacle, a planning path that avoids the obstacle is generated; or A satellite signal map of the working area is obtained, and a region where the satellite intensity is greater than a preset value is obtained, and the navigation path is planned to the region where the satellite intensity is greater than the preset value; or A path that avoids direct sunlight of the visual sensor is planned; The mobile robot is moved to the first preset position according to the navigation path.

18. The recharging control method of claim 17, wherein, The step of moving the mobile robot to the first preset position according to the navigation path further comprises: The mobile robot is positioned based on the environment information obtained by the satellite positioning device and the visual sensor, and the mobile robot is controlled to move to the first preset position along the navigation path according to the positioning information.

19. A return-to-base control system for a mobile robot, wherein, The return charging control system comprises: The mobile module is configured to control the mobile robot to move to a first preset position when the mobile robot needs to be recharged and a preset movement condition is met. The rotating module is configured to control the mobile robot to rotate at the first preset position. The first judging module is configured to judge whether the mobile robot can obtain a first recharging signal. The second judging module is configured to judge whether the mobile robot can obtain a second recharging signal when the first judging module judges that the mobile robot cannot obtain the first recharging signal. The recharging module is configured to guide the mobile robot to be recharged according to the second recharging signal when the mobile robot can obtain the second recharging signal.

20. A computer program product, wherein, The computer program product stores computer readable instructions which can be executed by at least one processor to enable the at least one processor to perform the steps of the recharging control method of the mobile robot according to claim 1.

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