Automatic obstacle avoidance method and system for mobile robot

Abstract

The invention discloses an automatic obstacle avoidance method and system for a mobile robot, and relates to the field of robot automatic obstacle avoidance, two groups of data of robot basic data and obstacle contour data are collected, the obstacle contour data are analyzed and screened, and the screened obstacle contour data are reference base points for robot obstacle avoidance; different obstacle avoidance paths are calculated by using a robot obstacle avoidance rotation angle formula according to the obtained reference base point, and the robot automatically selects one obstacle avoidance path to perform moving obstacle avoidance; through real-time detection in the moving process of the robot, it is ensured that the robot does not touch the obstacle in the moving process, and obstacle avoidance is successful. According to the invention, the external contour point of the detected obstacle is simplified into one or more reference base points, so that the obstacle avoidance processing efficiency, precision and stability of the robot are improved; the method not only reduces the complexity of data processing and calculation, but also improves the operational capability and obstacle avoidance performance of the robot.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of automatic obstacle avoidance of robots, and specifically to an automatic obstacle avoidance method and system for mobile robots. Background Art

[0002] Robot obstacle avoidance is a key link in robotics technology, which involves the robot sensing and judging obstacles in the surrounding environment to plan a safe movement path. Robot obstacle avoidance technology is widely used in various fields, such as sweeping robots and smart washing machines in smart homes, which help robots avoid collisions with obstacles in the home; smart express vehicles and robot food delivery in logistics and distribution, which improve the efficiency and safety of logistics and distribution; unmanned combat and electronic reconnaissance in the military field, which help robots avoid collisions with terrain and enemy obstacles.

[0003] When the robot perceives environmental obstacles, it still has the following defects: 1. Too much obstacle data is detected, resulting in low efficiency of the robot processing system in data processing. The complicated data processing reduces the robot system's computing power, and it seems that it cannot achieve the best state in real-time processing; 2. The robot processing system has a high-load operation for a long time, which leads to an increase in the system error rate, affecting the normal operation time of the robot and reducing its service life. In summary, there is an obstacle avoidance data optimization problem in the existing technology that needs to be solved urgently. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide an automatic obstacle avoidance method and system for a mobile robot to solve the technical problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The automatic obstacle avoidance method for a mobile robot comprises the following steps:

[0007] Collect two sets of data: basic data of the robot and obstacle contour data. The basic data of the robot specifically includes the robot rotation torque, the maximum width of the robot, and the maximum height of the robot; the obstacle contour data specifically includes a set of obstacle contour points obtained by a radar sensor set on the robot;

[0008] The obstacle contour data is analyzed and screened based on the basic data of the robot. The screened obstacle contour data is the reference base point for the robot to avoid obstacles. The reference base point is specifically the set of vertices at the left and right ends of the obstacle contour.

[0009] Based on the reference base point and the basic data of the robot, different obstacle avoidance paths are calculated using the preset robot obstacle avoidance rotation angle formula. According to the preset obstacle avoidance path selection conditions, the robot automatically selects one of the obstacle avoidance paths to move and avoid obstacles;

[0010] Based on intelligent algorithms and radar sensors, real-time detection is performed during the movement of the robot, and the robot's obstacle avoidance path is adjusted.

[0011] Preferably, the maximum height of the robot is the height from the ground to the highest point of the robot top, and the maximum width of the robot is the diameter of the largest circle formed by the robot outer contour sweeping when the robot remains stationary and rotates once, that is, the following conditions are met:

[0012] L=2r

[0013] L: represents the maximum width of the robot; r: represents the radius of the largest circle formed by the robot's outer contour when the robot rotates one circle.

[0014] Preferably, the analysis and screening is specifically to use the maximum height of the robot as a range reference, and to use an intelligent algorithm to analyze and screen the obstacle contour data, specifically satisfying the following equation:

[0015]

[0016] Among them, V1 and v2 represent the left vertex and the right vertex of the obstacle within the range reference of the robot's maximum height, respectively;

[0017] P o : represents the set of obstacle contour points within the range reference of the robot's maximum height;

[0018] CH(P o ): represents the tip of the obstacle contour point set within the range reference of the robot's maximum height;

[0019] Represents the vertex set corresponding to the tip set in the obstacle contour point set;

[0020] d(p1, p2): represents the vector modulus between vertex p1 and vertex p2 in the vertex set;

[0021] (v1, v2): indicates the reference point for the robot to avoid obstacles;

[0022] Represents the vertices p1 and p2 with the largest vector modulus.

[0023] Preferably, the set of reference base points is denoted as

[0024]

[0025] Among them, the reference base point v located at the left end of the obstacle contour i Satisfies the following equation:

[0026]

[0027] v i-1 , v i-2 :Represented as taking v2 as the reference, in the obstacle contour point set P o The two reference points to be found in

[0028] The reference base point v is located at the right end of the obstacle contour j Satisfies the following equation:

[0029]

[0030] v j-1 , v j-2 :Represented as taking v1 as the reference, in the obstacle contour point set P o Two reference points to look for in .

[0031] Preferably, the robot obstacle avoidance rotation angle formula is specifically as follows:

[0032]

[0033] Where, b: represents the minimum rotation angle required for the robot to avoid obstacles;

[0034] d v : Indicates the distance between the robot and the reference base point.

[0035] θ: represents the angle between the robot’s current orientation and the reference base point v.

[0036] Preferably, the obstacle avoidance path selection condition is specifically to select the path with the smallest obstacle avoidance rotation angle of the robot, and when the obstacle avoidance rotation angles of the robots are the same, the path with the smaller distance between the robot and the reference base point is preferentially selected.

[0037] An automatic obstacle avoidance system for a mobile robot, comprising a data acquisition module, a data processing module, a path simulation module, a control adjustment module, and a database;

[0038] The data acquisition module is connected to the data processing module and is used to directly input the basic data of the robot through the programming interface and obtain the obstacle contour data through the radar sensor, and send the obtained data to the data processing module in real time;

[0039] The data processing module is used to screen the obstacle contour data based on the basic data of the robot, extract the set of left and right vertices as reference base points, and calculate the rotation angle required for obstacle avoidance according to the obstacle avoidance rotation angle formula; and send the calculated reference base point and rotation angle to the path simulation module in real time;

[0040] The path simulation module is used to calculate multiple possible obstacle avoidance paths based on the reference base point and the basic data of the robot using the preset robot obstacle avoidance rotation angle formula; and automatically select an optimal obstacle avoidance path according to the preset obstacle avoidance path selection conditions;

[0041] The control adjustment module is used to receive obstacle data acquired by the radar sensor in real time during the robot's obstacle avoidance movement, and adjust the robot's obstacle avoidance path in real time; if a potential collision risk is detected, the robot's movement is immediately stopped, and the robot's obstacle avoidance path is readjusted;

[0042] The database is used to back up and store the system's reference base points, robot basic data, obstacle contour data, and obstacle avoidance paths.

[0043] In summary, the present invention mainly has the following beneficial effects:

[0044] In the optimization of robot obstacle avoidance processing, this system can greatly reduce the amount of data to be processed by simplifying the external contour points of the detected obstacles into a single or several reference base points. This not only reduces the complexity of data processing, but also reduces the consumption of computing resources, allowing the robot to handle obstacle avoidance tasks more efficiently; at the same time, after data simplification, the amount of calculation required by the robot is reduced, thereby increasing the computing speed. This enables the robot to respond to environmental changes more quickly, make obstacle avoidance decisions in a timely manner, and ensure safe movement.

[0045] With the optimized intelligent algorithms, the robot's obstacle avoidance ability can be further enhanced. These algorithms can adaptively adjust parameters and optimize obstacle avoidance strategies, so that the robot can perform well in different environments and conditions. At the same time, through reasonable base point selection and algorithm optimization, the accuracy of obstacle avoidance can be improved while ensuring computational efficiency. The robot can more accurately identify the location and shape of obstacles, thereby formulating a more precise obstacle avoidance path;

[0046] Secondly, the application of data simplification and optimization algorithms can reduce the requirements for robot hardware to a certain extent. This means that while maintaining the same obstacle avoidance performance, a lower-cost hardware platform can be used to reduce the overall cost of the robot. Based on simplified data representation and optimized intelligent algorithms, the robot obstacle avoidance system is easier to expand and upgrade. With the continuous advancement of technology, new algorithms or technologies can be easily introduced to further enhance the robot's obstacle avoidance capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a framework diagram of the overall steps of the method of the present invention;

[0048] Figure 2 It is a framework diagram of the overall system structure of the present invention. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0050] Example

[0051] like Figure 1 He Ru Figure 2 As shown, the automatic obstacle avoidance method for a mobile robot comprises the following steps:

[0052] Collect two sets of data: robot basic data and obstacle contour data. The robot basic data specifically includes the robot rotation torque, the robot maximum width, and the robot maximum height; the obstacle contour data specifically includes the obstacle contour point set obtained by the radar sensor set on the robot;

[0053] The obstacle contour data is analyzed and screened based on the robot's basic data. The screened obstacle contour data is the reference base point for the robot to avoid obstacles. The reference base point is specifically the set of vertices at the left and right ends of the obstacle contour.

[0054] Based on the reference base point and the basic data of the robot, different obstacle avoidance paths are calculated using the preset robot obstacle avoidance rotation angle formula. According to the preset obstacle avoidance path selection conditions, the robot automatically selects one of the obstacle avoidance paths to move and avoid obstacles;

[0055] Based on intelligent algorithms and radar sensors, real-time detection is performed during the movement of the robot, and the robot's obstacle avoidance path is adjusted to ensure that the robot does not touch obstacles during movement and successfully avoids obstacles.

[0056] The maximum height of the robot is the height from the ground to the highest point on the top of the robot. The maximum width of the robot is the diameter of the largest circle formed by the robot's outer contour when the robot remains stationary and rotates once, that is, it meets the following conditions:

[0057] L=2r

[0058] L: represents the maximum width of the robot; it is the theoretical minimum width. In practical applications, a threshold is added to L to expand the width of the robot, but the threshold should not be too large, otherwise the controllable range of the robot's movement will become smaller. r: represents the radius of the largest circle formed by the robot's outer contour sweep after one rotation of the robot.

[0059] The analysis and screening specifically uses the robot's maximum height as a range reference, uses an intelligent algorithm to calculate the obstacle contour data, and obtains the reference base point for the robot's obstacle avoidance, which specifically satisfies the following equation:

[0060]

[0061] Among them, V1 and v2 represent the left vertex and the right vertex of the obstacle within the range reference of the robot's maximum height, respectively. In the application, they are the outer contour replacement of the obstacle. In robot obstacle avoidance, what is avoided is the contact between points and surfaces, or between points and points, so the object is simplified in this way.

[0062] P o : represents the set of obstacle contour points within the range reference of the robot's maximum height;

[0063] CH(P o ): represents the tip of the obstacle contour point set within the range reference of the robot's maximum height;

[0064] Represents the vertex set corresponding to the tip set in the obstacle contour point set;

[0065] d(p1, p2): represents the vector modulus between vertex p1 and vertex p2 in the vertex set;

[0066] (v1, v2): indicates the reference point for the robot to avoid obstacles;

[0067] Represents the vertices p1 and p2 with the largest vector modulus.

[0068] The set of reference base points is denoted by

[0069]

[0070] Among them, the reference base point v located at the left end of the obstacle contour i Satisfies the following equation:

[0071]

[0072] v i-1 , v i-2 :Represented as taking v2 as the reference, in the obstacle contour point set P o The two reference points to be found in

[0073] The reference base point v is located at the right end of the obstacle contour j Satisfies the following equation:

[0074]

[0075] v j-1 , v j-2 :Represented as taking v1 as the reference, in the obstacle contour point set P o Two reference points to look for in .

[0076] V1 and V2 represent the reference base points with the largest vector modulus length in the set of vertices at the left end and right end of the obstacle within the range reference of the robot's maximum height, respectively;

[0077] v i-1 is the reference point with v2 as the second largest vector modulus in the vertex set, v i It is the reference base point with the third largest vector modulus in the vertex set;

[0078] v j-1 is the reference point with v1 as the second largest vector modulus in the vertex set, v j It is the reference base point with the third largest vector modulus in the vertex set.

[0079] The robot's obstacle avoidance rotation angle formula is as follows:

[0080]

[0081] Where, b: represents the minimum rotation angle required for the robot to avoid obstacles;

[0082] d v : Indicates the distance between the robot and the reference base point.

[0083] θ: represents the angle between the robot’s current orientation and the reference base point v.

[0084] The obstacle avoidance path selection condition is specifically to select the path with the smallest obstacle avoidance rotation angle of the robot. When the obstacle avoidance rotation angles of the robots are the same, the path with the smallest distance between the robot and the reference base point is preferentially selected.

[0085] An automatic obstacle avoidance system for a mobile robot includes a data acquisition module 10, a data processing module 20, a path simulation module 30, a control adjustment module 40, and a database 50;

[0086] The data acquisition module 10 is connected to the data processing module 20 and is used to directly input the basic data of the robot through the programming interface and obtain the obstacle contour data through the radar sensor, and send the obtained data to the data processing module 20 in real time;

[0087] The data processing module 20 is used to screen the obstacle contour data based on the basic data of the robot, extract the set of vertices at the left and right ends as the reference base points, and calculate the rotation angle required for obstacle avoidance according to the obstacle avoidance rotation angle formula; and send the calculated reference base point and rotation angle to the path simulation module 30 in real time;

[0088] The path simulation module 30 is used to calculate multiple possible obstacle avoidance paths based on the reference base point and the basic data of the robot using the preset robot obstacle avoidance rotation angle formula; and automatically select an optimal obstacle avoidance path according to the preset obstacle avoidance path selection conditions.

[0089] The control adjustment module 40 is used to receive obstacle data obtained by the radar sensor in real time during the robot's obstacle avoidance movement, and adjust the robot's obstacle avoidance path in real time; if a potential collision risk is detected, the robot's movement is immediately stopped and the robot's obstacle avoidance path is readjusted.

[0090] The database 50 is used to back up and store the system's reference base points, robot basic data, obstacle contour data, and obstacle avoidance paths; and is used to generate reports for the robot's obstacle avoidance experiments and provide a reference for the robot's obstacle avoidance.

[0091] It should be noted that, in this embodiment, in the data acquisition module 10, within the height range of the robot and with an additional 10 cm fault tolerance space, the original contour point set P of the obstacle in front of the robot under radar detection is o , and for the set P o Directly obtain 6 reference points at both ends of the obstacle, that is, 3 at each end. Find the two vertices v1 and v2 that are farthest apart, which roughly correspond to the two ends of the obstacle. For each endpoint, such as V1, in Among the vertices, find the second and third farthest vertices from the endpoint, recorded as v3 and v4; similarly, for the v2 endpoint, find v5 and v6 accordingly; these 6 vertices constitute the reference point set for calculating the robot's obstacle avoidance route.

[0092] In the data processing module 20, by We can directly determine v1, v2, and accordingly find Determine the second farthest vertex and the third farthest vertex Based on the same logic, for the v2 endpoint, find v5 and v6 accordingly, that is, The argmax operation here may return multiple points if the distance is the same, but in practical applications, we usually need to select a unique point, which can be achieved by adding an additional rule, that is, selecting the first point encountered; reference point set for:

[0093] Then using the radar data, we can get the set of obstacle reference points The angle θ relative to the current orientation of the robot is usually obtained by measuring the angle difference between the radar beam and the reflected wave of the obstacle. According to the distance data d, measured by the radar, the minimum passable width of the robot is close to L. In actual calculations, L can be enlarged, that is, a value greater than L is set to represent the passable width of the robot to avoid scratching with obstacles. Taking v1 as the reference point, the minimum angle b that the robot needs to turn is calculated by the above-mentioned formula. If the robot needs to turn in another direction, that is, v2, the calculation process is similar, but the sign of the angle will be opposite.

[0094] The control adjustment module 40 is based on v3, v4, v5, and v6. After the robot starts to move, the system control adjustment module 40 can detect the relative distance between v3, v4, v5, and v6 and the robot in real time. If the distance is too small and there is a risk of collision, the robot stops replanning the obstacle avoidance path.

[0095] The path simulation module 30 in the system uses a reference point set Six feasible routes are proposed. By setting the obstacle avoidance path selection conditions, that is, selecting the path with the smallest obstacle avoidance rotation angle of the robot, and giving priority to the path with the smaller distance between the robot and the reference base point when the obstacle avoidance rotation angles of the robots are the same; the robot's obstacle avoidance movement is started.

[0096] If the robot needs to perform obstacle avoidance motion, the minimum rotation angle b needs to be converted into the angle that the front outer wheel of the robot responsible for turning needs to rotate. In practice, not all robots turn in this way. This embodiment uses a more common and common motion method for illustration.

[0097] This can be done by β = arctan(sin(b)sec 2 (b)) and obtain the angle β that the front outer wheel needs to rotate. The robot movement control system controls the rotation of the robot based on β.

[0098] The working principle of the present invention is:

[0099] Under radar detection, only the set of front obstacle contour points P within the robot's height range is obtained. o , optimize the data at the beginning of data collection, reduce unnecessary or non-essential reference data to be input into the control system, reduce the pressure on the system, and Find the two farthest vertices v1 and V2, where v1 and v2 represent the reference base points of the object's touchable outline.

[0100] According to the distance data d measured by radar v, that is, the distance between the robot and the reference base point, and based on the robot's minimum passable width L, with v1 as the reference base point, the minimum angle b that the robot needs to turn is calculated using the above-mentioned formula. If the robot needs to turn in another direction, that is, v2, the calculation process is similar, but the sign of the angle will be opposite.

[0101] The path simulation module 30 in the system plans several feasible routes through a set of reference points, and sets the obstacle avoidance path selection condition, that is, selects the path with the smallest obstacle avoidance rotation angle. When the obstacle avoidance rotation angles of the robots are the same, the path with a smaller distance between the robot and the reference base point is preferentially selected; the robot's obstacle avoidance movement begins; as for the remaining reference points, the system control adjustment module 40 can be used to detect the relative distance between the reference point and the robot in real time after the robot starts moving. If the distance is too small and there is a risk of collision, the robot stops replanning the obstacle avoidance path.

[0102] This can be done by β = arctan(sin(b)sec 2 (b)) and obtain the angle β that the front outer wheel needs to rotate. The robot movement control system controls the rotation of the robot based on β.

[0103] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention.

Claims

1. An automatic obstacle avoidance method for a mobile robot, characterized in that: The following steps are involved: S1. Data collection: Collect basic robot data and obstacle contour data. The basic robot data specifically includes the robot rotation torque, the maximum width of the robot, and the maximum height of the robot. The obstacle contour data specifically includes a set of obstacle contour points obtained by a radar sensor set on the robot. S2, data processing: Analyze and screen the obstacle contour data based on the basic data of the robot. The screened obstacle contour data is the reference base point for the robot to avoid obstacles. The reference base point is specifically the set of vertices at the left and right ends of the obstacle contour. S3, motion planning: Based on the reference base point and the basic data of the robot, different obstacle avoidance paths are calculated using the preset robot obstacle avoidance rotation angle formula. According to the preset obstacle avoidance path selection conditions, the robot automatically selects one of the obstacle avoidance paths to move and avoid obstacles; S4, motion execution: When moving on an obstacle avoidance path, based on intelligent algorithms and radar sensors, real-time detection is performed during the robot's movement to adjust the robot's obstacle avoidance path.

2. The automatic obstacle avoidance method for a mobile robot according to claim 1, characterized in that: The maximum height of the robot is the height from the ground to the highest point of the robot. The maximum width of the robot is the diameter of the largest circle formed by the robot's outer contour when the robot remains stationary and rotates once, that is, the following conditions are met: L＝2r L: represents the maximum width of the robot; r: represents the radius of the largest circle formed by the robot's outer contour when the robot rotates one circle.

3. The automatic obstacle avoidance method for a mobile robot according to claim 2, characterized in that: The analysis and screening specifically uses the maximum height of the robot as a range reference, uses an intelligent algorithm to analyze and screen the obstacle contour data, and obtains a reference base point for the robot to avoid obstacles, which specifically satisfies the following equation: Among them, V1 and V2 represent the left vertex and the right vertex of the obstacle within the range reference of the robot's maximum height, respectively; P o : represents the set of obstacle contour points within the range reference of the robot's maximum height; CH(P o ): represents the tip of the obstacle contour point set within the range reference of the robot's maximum height; Represents the vertex set corresponding to the tip set in the obstacle contour point set; d(p1, p2): represents the vector modulus between vertex p1 and vertex p2 in the vertex set; (v1, v2): indicates the reference point for the robot to avoid obstacles; Represents the vertices p1 and p2 with the largest vector modulus.

4. The automatic obstacle avoidance method for a mobile robot according to claim 3, characterized in that: The set of reference base points is denoted as Among them, the reference base point V located at the left end of the obstacle outline i Satisfies the following equation: v i-1 , v i-2 :Represented as taking v2 as the reference, in the obstacle contour point set P o The two reference points to be found in The reference base point v is located at the right end of the obstacle contour j Satisfies the following equation: v j-1 , v j-2 :Represented as taking v1 as the reference, in the obstacle contour point set P o Two reference points to look for in .

5. The automatic obstacle avoidance method for a mobile robot according to claim 2, characterized in that: The robot obstacle avoidance rotation angle formula is specifically as follows: Where, b: represents the minimum rotation angle required for the robot to avoid obstacles; d v : Indicates the distance between the robot and the reference base point. θ: represents the angle between the robot’s current orientation and the reference base point v.

6. The automatic obstacle avoidance method for a mobile robot according to claim 1, characterized in that: The obstacle avoidance path selection condition is specifically to select a path with the smallest obstacle avoidance rotation angle of the robot, and when the obstacle avoidance rotation angles of the robots are the same, a path with a smaller distance between the robot and the reference base point is preferentially selected.

7. An automatic obstacle avoidance system for a mobile robot, applied to the automatic obstacle avoidance method for a mobile robot according to any one of claims 1 to 7, characterized in that: It includes a data acquisition module (10), a data processing module (20), a path simulation module (30), a control adjustment module (40), and a database (50); The data acquisition module (10) is connected to the data processing module (20) and is used to directly input basic data of the robot through a programming interface and to obtain obstacle contour data through a radar sensor, and to send the obtained obstacle contour data to the data processing module (20) in real time; The data processing module (20) is used to screen obstacle contour data based on the basic data of the robot, extract the set of left and right end vertices as reference base points, and calculate the rotation angle required for obstacle avoidance according to the obstacle avoidance rotation angle formula; The calculated reference base point and rotation angle are sent to the path simulation module (30) in real time; The path simulation module (30) is used to calculate multiple possible obstacle avoidance paths based on the reference base point and the basic data of the robot using a preset robot obstacle avoidance rotation angle formula; and automatically select an optimal obstacle avoidance path according to a preset obstacle avoidance path selection condition; The control adjustment module (40) is used to receive obstacle contour point data acquired by the radar sensor in real time during the robot's obstacle avoidance movement, and adjust the robot's obstacle avoidance path in real time; if a potential collision risk is detected, the robot's movement is immediately stopped, and the robot's obstacle avoidance path is readjusted; The database (50) is used to back up and store the system's reference base points, robot basic data, obstacle contour data, and obstacle avoidance paths.

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