Escape method

Abstract

An escape method for a self-moving device. The method comprises: determining whether a self-moving device is in a trapping scene or not; if the self-moving device is in the trapping scene, acquiring circumferential obstacle information of the self-moving device, wherein the obstacle information comprises passing gaps meeting a preset distance condition and allowing the self-moving device to pass through; acquiring a current point of the self-moving device and a target point, wherein the target point is a local planning target point; and selecting a passing gap on the basis of the target point, so that in the direction from the current point to the target point, the self-moving device selects a nearby passing gap to escape, and thus the overall path is more reasonable, thereby avoiding escaping through the passing gap in a direction far away from the direction from the current point to the target point.

Description

Escape method Technical Field

[0001] The present invention relates to the field of self-propelled equipment, and more particularly to a method for escaping from distress. Background Art

[0002] Nowadays, mobile devices often encounter many complex siege scenarios during operation. Conventional methods such as obstacle avoidance are used to escape from siege scenarios. However, when trying to escape, the path is often complex and the escape efficiency is low. Even if the escape is successful, the subsequent path needs to be replanned, which may overlap with the path before being trapped, resulting in repeated work. Summary of the Invention

[0003] In order to solve at least one of the technical problems raised above, the present application provides a method for escaping from a predicament, which can combine local planning with a certain strategy to select the optimal path for escaping from a predicament, so as to make the overall path more reasonable.

[0004] The present application provides a method for escaping a self-propelled device, the method comprising:

[0005] Determine whether the self-moving device is in a siege scene; when the self-moving device is in a siege scene, obtain circumferential obstacle information of the self-moving device, the obstacle information including: a passage gap that meets a preset distance condition for the self-moving device to pass through; obtain the current point and target point of the self-moving device, the target point being a locally planned target point; select the passage gap according to the target point, so that the self-moving device selects the nearest passage gap from the current point toward the target point to escape.

[0006] Preferably, the method for selecting the passage gap according to the target point includes: calculating the angle bisector of the angle formed by the line connecting the two end points of the passage gap and the current point of the self-mobile device and the angle value formed by the line connecting the current point of the self-mobile device and the target point; comparing the angle values ​​corresponding to each passage gap, and selecting the passage gap corresponding to the minimum angle value as the passage gap closest to the direction of the self-mobile device from the current point toward the target point.

[0007] Preferably, the method of selecting the passage gap according to the target point includes:

[0008] Calculate the inclination value K from the current point of the mobile device to the target point goal :

[0009] Calculate the inclination value K of the angle bisector formed by the two end points of the passage gap and the current point of the mobile device bisector [i]: Kbisector [i]=normalization(K start [i],0.5*normalization(K end [i],-K start [i]))

[0010] Where i = 1…n

[0011] Calculate K goal and K bisector [i] The absolute value of the difference, the minimum value K of the absolute value is selected optimal , the minimum value K optimal The corresponding passage gap is the nearest passage gap in the direction from the current point to the target point of the mobile device: K optimal =min(abs(K bisector [i]-K goal )).

[0012] Preferably, determining whether the self-moving device is in a besieged scene includes:

[0013] Identify the circumferential obstacle information of the self-moving device, and determine whether the obstacles all meet the distribution condition, continuity condition, number of passage gaps condition, and minimum distance condition. If all conditions are met, the self-moving device is in a siege scenario; if any condition is not met, the self-moving device is not in a siege scenario.

[0014] Preferably, determining whether the obstacle satisfies the distribution condition includes:

[0015] Establishing a vehicle body coordinate system with the center of motion of the self-moving device as the origin and the front direction of the self-moving device as the positive direction of the X-axis;

[0016] The distribution of the circumferential obstacles of the self-moving device in the vehicle body coordinate system is determined. If obstacles are distributed in at least three quadrants of the vehicle body coordinate system, the distribution condition is satisfied.

[0017] Preferably, determining whether the obstacle satisfies the continuity condition includes: establishing a vehicle coordinate system with the center of motion of the self-moving device as the origin and the front direction of the self-moving device as the positive direction of the X-axis; calculating the distance between adjacent obstacle points, if it is less than a preset distance, it is a continuous obstacle; determining the continuity of the circumferential obstacles of the self-moving device in the vehicle coordinate system, if there are continuous obstacles in at least two quadrants of the vehicle coordinate system, the continuity condition is satisfied.

[0018] Preferably, the value of the preset distance one is between 50 cm and 70 cm.

[0019] Preferably, determining whether the obstacle meets the passage gap number condition includes: calculating the distance between adjacent obstacle points, and recording it as a passage gap if it is greater than a preset distance of two; determining the number of passage gaps, and if it is not less than 1, the passage gap number condition is met.

[0020] Preferably, the preset distance 2 is 1.5 times the width of the body of the self-moving device.

[0021] Preferably, determining whether the obstacle meets the minimum distance condition includes: calculating the distance from the obstacle point to the center of motion of the self-moving device, and selecting the minimum distance value; determining the numerical value of the minimum distance value and the preset distance three, and if the minimum distance value is not less than the preset distance three, the minimum distance condition is met.

[0022] Preferably, the preset distance three is a preset value that satisfies the self-spinning of the mobile device.

[0023] Preferably, the self-moving device rotates with the center of motion as the center toward the selected passage gap; a local path is planned according to the current point, the target point, and the selected passage gap, and escapes according to the planned path.

[0024] Preferably, the self-moving device's escape process further includes: real-time detection of obstacle information, and determining whether the obstacle information satisfies a preset escape condition; if so, the self-moving device continues to escape, otherwise, the escape is terminated.

[0025] Preferably, the preset escape condition is: the distance between the obstacle point and the line connecting the current point of the self-moving device and the center point of the selected passage gap is greater than a preset distance of four.

[0026] Preferably, the preset distance 4 is half of the width of the self-moving device.

[0027] The present application also provides a self-moving device including a control unit, which uses an escape method, and the escape method includes: judging whether the self-moving device is in a siege scene; when the self-moving device is in a siege scene, obtaining circumferential obstacle information of the self-moving device, and the obstacle information includes: a passage gap that meets a preset distance condition for the self-moving device to pass through; obtaining the current point and target point of the self-moving device, the target point being a locally planned target point; selecting the passage gap according to the target point, so that the self-moving device selects the nearest passage gap from the current point toward the target point to escape.

[0028] Preferably, the self-moving device further includes: a vehicle body; a walking unit for enabling the self-moving device to move; a sensing unit for acquiring external information around the self-moving device; and an operating unit for enabling the self-moving device to operate.

[0029] Preferably, the sensing unit includes at least one of a laser sensor, a visual sensor, and an infrared sensor.

[0030] Preferably, the self-moving device is a smart lawn mower, a sweeper, or an outdoor swimming pool cleaner.

[0031] The present application also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned escape method when executing the computer program.

[0032] The present application provides a method for escaping a self-moving device, which selects a nearby passageway gap from a current point toward a local planned target point to escape, so that the self-moving device still approaches the local target point during the escape, rather than escaping in a direction away from the local planned target point. The escape path is better, and the self-moving device can have a more reasonable path during the overall operation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a flow chart of the method for escaping from distress provided by the present application;

[0034] FIG2 is a calculation flow chart of the escape method provided by this application;

[0035] FIG3 is a flow chart of identifying trapped scenes in the escape method provided by the present application;

[0036] FIG4 is a schematic diagram of a siege scenario of a self-mobile device provided by this application;

[0037] FIG5 is a schematic diagram of another siege scenario of a self-mobile device provided by this application;

[0038] FIG6 is a schematic diagram of another siege scenario of a self-moving device provided by this application;

[0039] FIG7 is a schematic diagram of the application of the escape method of the present application in the siege scene of FIG5;

[0040] Figure 8 shows a scenario where the self-moving device provided by this application does not meet the siege scenario;

[0041] FIG9 is another scenario of a self-moving device provided by this application that does not meet the siege scenario. DETAILED DESCRIPTION

[0042] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. For example, terms such as "upper," "lower," "front," and "rear" indicating orientation or positional relationships are based solely on the orientation or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the disclosure. They do not indicate or imply that the device or element referred to must have a specific orientation or be constructed or operated in a specific orientation. Therefore, they should not be construed as limiting the disclosure.

[0043] The present application discloses a self-moving device, including a body, a travel unit, a sensing unit, a control unit, and an operating unit. The sensing unit is used to obtain external information about the self-moving device. Specifically, the sensing unit is a laser sensor, a visual sensor, or an infrared sensor. The control unit is used to receive external information from the sensing unit and control the travel unit and / or the operating unit to operate according to the external information. The self-moving device of the present application can be a smart lawn mower, a sweeper, an outdoor pool cleaner, or other equipment.

[0044] During operation, mobile devices often encounter many obstacles that can affect their operation. The external information acquired by the sensing unit includes information about circumferential obstacles. This application also discloses a method for escaping from an obstacle. Upon receiving the information about circumferential obstacles, the control unit executes the method.

[0045] The escape method includes: determining whether the mobile device is in a trapped scene;

[0046] When the mobile device is in a besieged scene, obtain obstacle information around the mobile device, the obstacle information including: a passage gap that meets a preset distance condition for the mobile device to pass through;

[0047] Get the current point and target point from the mobile device. The target point is the local planning target point.

[0048] A passage gap is selected according to the target point so that the mobile device can choose the nearest passage gap to escape from the current point toward the target point.

[0049] Preferably, the control unit determines whether the mobile device is in a besieged scene based on the circumferential obstacle information obtained by the sensing unit, and the specific method includes:

[0050] Identify obstacles surrounding the mobile device and determine whether the obstacles meet the distribution, continuity, number of gaps, and minimum distance requirements. If all meet these requirements, the mobile device is considered trapped. If any of these requirements are not met, the mobile device is not considered trapped. The distribution, continuity, number of gaps, and minimum distance requirements can be determined simultaneously or sequentially according to a preset time sequence; this is not a limitation here.

[0051] Specifically, judging whether obstacles meet distribution conditions includes:

[0052] Establish a vehicle coordinate system with the center of motion of the self-moving device as the origin and the direction of the self-moving device's front as the positive direction of the X-axis. Determine the distribution of obstacles circumferential to the self-moving device in the vehicle coordinate system. If obstacles are distributed in at least three quadrants of the vehicle coordinate system, then the distribution angle of the obstacles in the vehicle coordinate system is greater than 180 degrees, and the distribution condition is met; otherwise, it is not met. For example, as shown in Figures 4, 5, and 6, obstacles are distributed in more than three quadrants, thus meeting the distribution condition. As shown in Figure 8, obstacles are distributed in only two quadrants, thus not meeting the distribution condition.

[0053] Specifically, judging whether the obstacle meets the continuity condition includes:

[0054] Calculate the distance between adjacent obstacle points. If it is less than the preset distance, it is a continuous obstacle.

[0055] The continuity of the circumferential obstacles of the self-moving device in the vehicle coordinate system is determined. If there are continuous obstacles in at least two quadrants of the vehicle coordinate system, the continuity condition is met. The continuity condition is used to avoid sparse obstacle points or continuous obstacles in only a local area. The preset distance one can be set to a specific parameter, any parameter between 50cm and 70cm, with the preferred preset distance one being 60cm. For example, as shown in Figure 9, the continuity condition is not met because the obstacle points are very sparse.

[0056] Specifically, determining whether an obstacle meets the number of clearance gaps includes:

[0057] Calculate the distance between adjacent obstacle points. If it is greater than the preset distance, record it as a passage gap.

[0058] Determine the number of passage gaps. If it is not less than 1, the passage gap number condition is met. The preset distance 2 is set according to the width of the vehicle body. It can be 1.2-1.8 times the width of the vehicle body so that the vehicle body has enough space to pass through the passage gap. Preferably, the preset distance 2 is 1.5 times the width of the vehicle body. For example, when the vehicle body width is 40 cm, the preset distance 2 is 60 cm. As shown in Figure 4, there is a passage gap a, which has 1 passage gap, and the passage gap number condition is met; as shown in Figure 5, there are passage gaps b1, b2, and b3, which have 3 passage gaps, and the passage gap number condition is met; as shown in Figure 6, there are passage gaps c1 and c4, and although openings c2 and c3 are gaps, they cannot be passed because the distance is less than the preset distance 2 and are not counted in the number. Therefore, there are 2 passage gaps, and the passage gap number condition is met.

[0059] Specifically, determining whether an obstacle meets the minimum distance condition includes:

[0060] Calculate the distance from the obstacle point to the center of motion of the mobile device and select the minimum distance;

[0061] The minimum distance value is compared to the preset distance 3. If the minimum distance value is not less than the preset distance 3, the minimum distance condition is met. The minimum distance condition is used to determine whether the self-moving device can spin in the siege scene, so the preset distance 3 is the preset value that satisfies the self-moving device's spinning.

[0062] Secondly, when the mobile device is in a besieged scenario, information about the passage gap, the current point of the mobile device, and the target point are obtained. The target point is the local planning target point.

[0063] A passage gap is selected according to the target point so that the self-moving device can choose the nearest passage gap to escape from the current point toward the target point. In this way, the self-moving device generally always moves in the direction toward the local planned target point, rather than in the direction "the opposite" to the local planned target point.

[0064] The method of selecting the nearest passage gap from the current point toward the target point in the present application is through angle comparison, but it is not limited thereto and can also be selected in other ways. Specifically, the angle bisectors of the angles formed by the line connecting the two end points of the passage gap and the current point of the mobile device and the angle value formed by the line connecting the current point of the mobile device and the target point are calculated; the angle values ​​corresponding to each passage gap are compared, and the passage gap corresponding to the minimum angle value is selected as the passage gap nearest to the direction from the current point of the mobile device toward the target point. For example, as shown in Figure 7, M is the target point, the angle bisectors of the passage gaps b1, b2, and b3 and the angle value between M and the origin are calculated, the angle values ​​are compared, and the passage gap b2 corresponding to the minimum angle value is selected to escape.

[0065] More specifically, it is implemented through the angle function, specifically:

[0066] Calculate the inclination angle K from the current point of the mobile device to the target point goal :

[0067] Calculate the inclination value K of the angle bisector formed by the two end points of the passage gap and the current point of the mobile device bisector [i]: K bisector [i]=normalization(K start [i],0.5*normalization(K end [i],-K start [i]))

[0068] Where i = 1…n

[0069] Calculate K goal and K bisector [i] The absolute value of the difference, select the minimum absolute value K optimal , minimum value K optimal The corresponding passage gap is the nearest passage gap in the direction from the current point of the mobile device to the target point: K optimal =min(abs(K bisector [i]-K goal )).

[0070] Prioritize, the self-moving device rotates around the center of motion toward the selected passage gap; local path planning is performed based on the current point, target point, and the selected passage gap, and escapes according to the planned path.

[0071] Furthermore, the process of freeing the mobile device from distress also includes:

[0072] Obstacle information is detected in real time to determine whether the obstacle information meets the preset escape conditions. If so, the self-moving device continues to escape; otherwise, the escape is terminated. After terminating the escape, it can be re-determined whether the siege conditions are met. If the siege conditions are met, the escape method of this application is re-circulated. The preset escape conditions are: the distance between the obstacle point and the line connecting the current point of the self-moving device and the center point of the selected passage is greater than a preset distance four, which is half the width of the self-moving device. During the escape process, the dynamic changes of the obstacle are monitored, and the optimal path can be adjusted at any time.

[0073] The present application also discloses an electronic device, which includes a memory, a processor and a computer program stored in the memory and runable on the processor, and the processor executes the computer program to implement the above-mentioned method of escape. The electronic device is a computing device such as a server, a desktop computer, a tablet computer, a cloud server and a mobile terminal. The memory is a hard disk or memory in the electronic device, or a USB flash drive, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, or a flash card (FlashCard) plugged into the electronic device. The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc.

[0074] The present application also discloses a computer-readable storage medium having a computer program stored therein, which implements the above-mentioned method of escape when the computer program is executed by a processor. The computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium.

[0075] As can be seen from the above, the escape method disclosed in the present application, when the self-moving device is in a besieged scene, selects the nearest passage gap in the direction from the current point of the self-moving device toward the target point, so that the self-moving device always runs in the general direction of the local planning. The overall path is more reasonable, can avoid repeated path planning, and save power waste of the self-moving device.

[0076] The present invention is not limited to the specific embodiments described above. Those skilled in the art will readily appreciate that many alternatives to the outer rotor motor of the present invention exist without departing from the principles and scope of the present invention. The scope of protection of the present invention shall be determined by the claims.

Claims

1. A method for escaping from a predicament applied to a self-moving device, characterized in that: The method for escaping from the predicament comprises: Determining whether the mobile device is in a siege scenario; When the self-moving device is in a besieged scene, obtaining circumferential obstacle information of the self-moving device, the obstacle information including: a passage gap that satisfies a preset distance condition for the self-moving device to pass through; Obtaining the current point and target point of the self-mobile device, wherein the target point is a local planning target point; The passage gap is selected according to the target point, so that the mobile device selects the nearest passage gap from the current point toward the target point to escape.

2. The method for escaping from a difficult situation as claimed in claim 1, characterized in that: The method for selecting the passage gap according to the target point includes: Calculate the angle bisectors of the angles formed by the line connecting the two end points of the passage gap and the current point of the self-moving device and the angle value formed by the line connecting the current point of the self-moving device and the target point; The angle values corresponding to the passage gaps are compared, and the passage gap corresponding to the minimum angle value is selected as the passage gap closest to the direction of the mobile device from the current point toward the target point.

3. The method for escaping from a difficult situation according to any one of claims 1 or 2, characterized in that: The method for selecting the passage gap according to the target point includes: Calculate the inclination angle value K of the current point of the self - moving device to the target point goal : Calculate the inclination value K of the angular bisector of the angle formed by the two endpoints of the passing gap and the current point of the self - moving device bisector [i]: K bisector [i] = normalization(K start [i], 0.5 * normalization(K end [i], -K start [i])) Where i = 1…n Calculate K goal and K bisector [i] the absolute value of the difference, and select the minimum value K of the absolute value optimal , the minimum value K optimal the corresponding passage gap is the passage gap closest to the direction of the self-moving device from the current point towards the target point: K optimal = min(abs(K bisector [i] - K goal ))。 4. The method for escaping from a difficult situation as claimed in claim 1, characterized in that: Determining whether the mobile device is in a besieged scene includes: Identify the circumferential obstacle information of the self-moving device, and determine whether the obstacles all meet the distribution condition, continuity condition, passage gap quantity condition, and minimum distance condition. If all conditions are met, the self-moving device is in a siege scene; if any condition is not met, the self-moving device is not in a siege scene.

5. The method for escaping from a difficult situation as claimed in claim 4, characterized in that: Determining whether the obstacle satisfies the distribution condition includes: Establishing a vehicle body coordinate system with the motion center of the self-moving device as the origin and the front direction of the self-moving device as the positive direction of the X-axis; The distribution of the circumferential obstacles of the self-moving device in the vehicle body coordinate system is determined. If obstacles are distributed in at least three quadrants of the vehicle body coordinate system, the distribution condition is satisfied.

6. The method for escaping from a difficult situation as claimed in claim 4, characterized in that: Determining whether the obstacle satisfies the continuity condition includes: Establishing a vehicle body coordinate system with the motion center of the self-moving device as the origin and the front direction of the self-moving device as the positive direction of the X-axis; Calculate the distance between adjacent obstacle points. If it is less than the preset distance, it is a continuous obstacle. The continuity of the circumferential obstacles of the self-moving device in the vehicle body coordinate system is determined if there are continuous obstacles in at least two quadrants of the vehicle body coordinate system and if the continuity condition is met.

7. The method for escaping from a difficult situation as claimed in claim 4, characterized in that: Determining whether the obstacle meets the traffic gap quantity condition includes: Calculate the distance between adjacent obstacle points, and if it is greater than the preset distance two, record it as a clearance gap; Determine the number of passage gaps. If it is not less than 1, the passage gap number condition is met.

8. The method for escaping from a difficult situation as claimed in claim 4, characterized in that: Determining whether the obstacle meets the minimum distance condition includes: Calculate the distance from the obstacle point to the center of motion of the self-moving device and select the minimum distance; The minimum distance value and the preset distance three are determined. If the minimum distance value is not less than the preset distance three, the minimum distance condition is met.

9. The method for escaping from a difficult situation as claimed in claim 1, characterized in that: The self-moving device rotates with the center of motion as the center of the circle toward the selected passage gap; Perform local path planning based on the current point, the target point, and the selected traffic gap, and escape from the predicament along the planned path.

10. The method for escaping from a difficult situation as claimed in claim 1, characterized in that: The process of the self-moving device getting out of trouble also includes: Detect obstacle information in real time and determine whether the obstacle information meets a preset escape condition. If so, the self-moving device continues to escape, otherwise, the escape is terminated; The preset escape conditions are: The distance between the obstacle point and the line connecting the current point of the self-moving device and the center point of the selected passage gap is greater than a preset distance of four.

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