A multi-robot anti-collision method and system

Abstract

The present invention discloses a method and system for multi-robot anti-collision, belonging to the technical field of multi-robot cooperative control. For at least two robots, each robot is equipped with a set of wireless ad hoc network communication equipment; calculation is performed on the robot end to obtain the robot's own target speed, and the anti-collision speed is calculated according to the distance with other robots in the network, and the target speeds of other robots in the network are obtained and each adjustment coefficient is determined according to their distance; the robot's own target speed, the anti-collision speed, and the adjustment speed vectors of other robots are added to calculate the final target speed of the robot; each robot in the network calculates its own final target speed and runs according to its own final target speed. The present invention can realize fast and effective transmission of information between robots, the method is simple and reliable, and can adapt to various complex formations and any number of robots.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-robot cooperative control, in particular to a multi-robot anti-collision method and system. Background Art

[0002] With the advancement of world science and technology, computer, communication and automation control technologies are changing with each passing day, and robot (including unmanned vehicles, drones, etc.) technology has achieved rapid development. Due to its unique advantages, robots are now widely used in military, warehousing, logistics, aerial photography, surveying and mapping, plant protection, power inspection, disaster relief and other fields. Multi-robot collaborative control can greatly improve the success probability of tasks, improve the efficiency of task completion, and can also realize formation performances, etc., and its application is becoming more and more extensive.

[0003] While multi-robot collaborative control brings huge advantages, it also brings hidden dangers to the safety of robot operation. Since there are multiple robots in the same area at the same time, the probability of collision between robots increases, especially when multiple robots are moving in formation and collaborating to perform tasks such as search and cargo delivery. How to avoid collisions between robots is a major obstacle to the development of multi-robot collaborative control technology.

[0004] For multi-robot anti-collision control, the dispatch center is usually used for unified dispatching, which controls the overall movement of the formation to reduce the intersection of the robot's movement paths, or controls the position change of all robots in batches to avoid collisions when the robots move. This method has complex processing logic, low efficiency, and poor processing effect on complex transformation situations. Summary of the invention

[0005] The technical task of the present invention is to address the above deficiencies and provide a multi-robot anti-collision method and system, which can realize fast and effective transmission of information between robots. The method is simple and reliable and can adapt to various complex formations and any number of robots.

[0006] The technical solution adopted by the present invention to solve the technical problem is:

[0007] A multi-robot anti-collision method, for at least two robots, each robot is equipped with a set of wireless ad hoc network communication equipment, the communication equipment can add all robots in the same working area to the same network, so that any robot in the network can communicate with all other robots, and any robot in the network broadcasts its own speed and position information to other robots;

[0008] Calculation is performed on the robot side to obtain the robot's own target speed, calculate the anti-collision speed based on the distance from other robots in the network, obtain the target speeds of other robots in the network and determine the adjustment coefficients of each target speed based on their distances to form an adjustment speed; the robot's own target speed, anti-collision speed, and other robots' adjustment speed vectors are added together to calculate the robot's final target speed;

[0009] Each robot in the network calculates its own final target speed and runs according to its own final target speed.

[0010] Among them, the robot's own target speed can make the robot move towards the target point; the anti-collision speed enables the robot to move away from other robots when it is close to other robots to avoid collision; the adjustment speed of other robots enables the robot to make advance adjustments according to the movement of other robots.

[0011] This method uses wireless ad hoc network technology combined with the robot's computing and processing capabilities to design a multi-robot anti-collision method with strong adaptability and fast processing speed. The wireless ad hoc network enables any robot to obtain information about other robots in the system in a timely and effective manner; the final result can be obtained by simply and quickly processing the data on the robot side, without the need for complex calculations and forwarding by the dispatch center; there is no need to consider the formation transformation logic in various situations, and it can adapt to various complex formation situations and systems with any number of robots.

[0012] Furthermore, a safety distance S is set, that is, when the distance between two robots is greater than S, it is considered that the two robots will not collide; the robot data greater than the safety distance S is not processed, and for the robots within the safety distance, after receiving the position and speed information of other robots, each calculates its final target speed.

[0013] Preferably, the safety distance S is determined according to the maximum moving speed and acceleration of the robot:

[0014] S=Vmax 2 / 2a+L,

[0015] Among them, Vmax is the maximum speed that the robot can reach, a is the maximum acceleration that the robot can reach, and L is the maximum diameter of the robot.

[0016] Preferably, let one of the robots be A, and A's own target speed be V1;

[0017] There are robots B, C, and D within the safe distance of A. The distances between A and B, C, and D are Sab, Sac, and Sad, respectively. Then, according to Sab, Sac, Sad, and the maximum movement speed of robot A, the anti-collision speeds Vab, Vac, and Vad are calculated, respectively, where the magnitudes of Vab, Vac, and Vad are inversely proportional to Sab, Sac, and Sad, respectively; the directions of Vab, Vac, and Vad are from B, C, and D to A, respectively; the vector sum of Vab, Vac, and Vad is calculated, which is the anti-collision speed, represented by V2, and V2=Vab+Vac+Vad;

[0018] The current actual moving speeds of robots B, C, and D are Vb, Vc, and Vd respectively. The coefficients of Vb, Vc, and Vd are determined according to Sab, Sac, and Sad. The speed multiplied by the coefficient is the adjustment speed. The sum of the adjustment speeds is called the lead adjustment speed, which is represented by V3.

[0019] Then the final target speed of robot A is: V=V1+V2+V3.

[0020] Preferably, the specific calculation formulas of the anti-collision speed quantities Vab, Vac, and Vad are as follows:

[0021] Vab=3×Vmax×(S-Sab) / Sab,

[0022] Vac=3×Vmax×(S-Sac) / Sac,

[0023] Vad = 3 × Vmax × (S-Sad) / Sad,

[0024] Where Vmax is the maximum movement speed that robot A can achieve.

[0025] Preferably, the advance adjustment speed V3 = KbVb+KcVc+KdVd, wherein the magnitudes of coefficients Kb, Kc, and Kd are inversely proportional to Sab, Sac, and Sad, respectively.

[0026] Preferably, the distance between the robot A and robots B, C, D is a two-dimensional space distance, and each robot sends its two-dimensional coordinate position to other robots in the network; the V1, Vb, Vc, Vd and Vab, Vac, Vad are all two-dimensional vectors.

[0027] Preferably, the distance between the robot A and robots B, C, and D is the Euclidean distance, and each robot sends its three-dimensional coordinate position to other robots in the network; the V1, Vb, Vc, Vd and Vab, Vac, and Vad are all three-dimensional vectors.

[0028] The present invention also claims protection for a multi-robot anti-collision system, wherein the system has at least two robots, each robot being equipped with a set of wireless ad hoc network communication equipment, through which any robot can communicate with all other robots;

[0029] Each robot in the system calculates its own final target speed according to the above-mentioned multi-robot anti-collision method and runs according to its own final target speed.

[0030] Preferably, each robot has a built-in processor that calculates its own target speed, anti-collision speed, advance adjustment speed and final target speed.

[0031] Compared with the prior art, the multi-robot anti-collision method and system of the present invention has the following beneficial effects:

[0032] This method is based on wireless ad hoc network technology, which can realize fast and effective information transmission and improve efficiency;

[0033] The final target speed of the robot is calculated by adding the robot's own target speed, anti-collision speed, and the speed vectors of other robots. The method is simple and reliable and can adapt to various complex formations and any number of robots.

[0034] Calculation is performed on the robot side, without going through the dispatch center, which improves the real-time nature of the adjustment. All robots can move at the same time, greatly shortening the time for robot position adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a diagram of the implementation process of the multi-robot anti-collision method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with specific embodiments.

[0037] An embodiment of the present invention provides a multi-robot collision avoidance method. For at least two robots, each robot is installed with a set of wireless ad hoc network communication equipment. The communication equipment can add all robots in the same working area to the same network, so that any robot in the network can communicate with all other robots, and any robot in the network broadcasts its own speed and position information to other robots.

[0038] The robot has its own processor, and the anti-collision calculations are performed on the robot side.

[0039] The robot obtains its own target speed V1 to move towards its own final target position; by obtaining the position information of other robots in the network, each anti-collision speed is calculated according to the distance from other robots, and the anti-collision speed V2 is obtained by adding them up; the target speeds of other robots in the network are obtained and each adjustment coefficient is determined according to their distance, and each adjustment speed is obtained by combining the target speed of each robot with its adjustment coefficient, and the advance adjustment speed V3 is obtained by adding the three vectors of the robot's own target speed V1, the anti-collision speed V2, and the advance adjustment speed V3 to obtain the final target speed of the robot.

[0040] Each robot in the network calculates its own final target speed and runs according to its own final target speed.

[0041] This embodiment takes a two-dimensional space as an example. A safety distance S is set. The value of the safety distance S is determined in advance according to the actual situation and is a fixed value. It needs to be determined according to the maximum moving speed and acceleration of the robot. In this embodiment, the determination method of the safety distance S is as follows:

[0042] S=Vmax 2 / 2a+L,

[0043] Among them, Vmax is the maximum speed that the robot can reach, a is the maximum acceleration that the robot can reach, and L is the maximum diameter of the robot.

[0044] When the distance between two robots is greater than S, it is considered that there is no possibility of collision between the two robots; the data of robots that are greater than the safety distance S are not processed, and for robots within the safety distance, after receiving the position and speed information of other robots, each calculates its final target speed.

[0045] 1. Assume that one of the robots is A, and A's own target speed is V1 (two-dimensional vector); when robot A receives the distance between itself and other robots in two-dimensional space (three-dimensional space corresponds to Euclidean distance), it does not process the robot data that is greater than the safety distance S. For robots within the safety distance, assume that robots B, C, and D are within the safety distance of A, and the distances between A and B, C, and D are Sab, Sac, and Sad, respectively.

[0046] 2. According to Sab, Sac, Sad, we calculate an anti-collision speed Vab, Vac, Vad (all two-dimensional vectors), the magnitudes of Vab, Vac, Vad are inversely proportional to Sab, Sac, Sad, that is, the closer to A, the greater the corresponding speed. The directions of Vab, Vac, Vad are from B, C, D to A, respectively. The vector sum V2 of the three is calculated as V2=Vab+Vac+Vad. Among them,

[0047] Vab=3×Vmax×(S-Sab) / Sab,

[0048] Vac=3×Vmax×(S-Sac) / Sac,

[0049] Vad = 3 × Vmax × (S-Sad) / Sad,

[0050] Vmax is the maximum movement speed that robot A can achieve.

[0051] 3. Get the current actual moving speeds of robots B, C, and D as Vb, Vc, and Vd (all two-dimensional vectors), and then calculate an advance adjustment speed value V3 = KbVb + KcVc + Kd*Vd, where the coefficients Kb, Kc, and Kd are inversely proportional to Sab, Sac, and Sad, respectively, that is, the closer the distance to A, the larger the corresponding coefficient.

[0052] 4. The final target speed of robot A is V=V1+V2+V3.

[0053] Among them, speed V1 enables robot A to fly towards the target point; the anti-collision speed V2 enables robot A to move away from other robots when it is close to other robots to avoid collision; speed V3 enables robot A to make advance adjustments based on the movements of other robots, and the closer the robot is to A, the greater the impact on A.

[0054] Perform the above processing on other robots in the network formation, calculate their respective final target speeds, and run according to their respective final target speeds.

[0055] If the robot works in three-dimensional space, such as a drone, the same method is extended to three dimensions, and the calculation method is the same as that of two-dimensional space.

[0056] In military, warehousing, logistics, plant protection, formation performance and other application scenarios, multiple robots are required to coordinate control and complete tasks together, but the coordinated control of multiple robots also brings hidden dangers to the operation safety of robots. Since there are multiple robots in the same area at the same time, the probability of collision between robots increases. The multi-robot anti-collision method based on wireless ad hoc network provided by this method can make full use of wireless ad hoc network technology, combined with the computing and processing capabilities of robots, to improve the safety of multi-robot coordinated control and prevent collisions between robots; it has strong adaptability and fast processing speed. The wireless ad hoc network enables any robot to obtain information from other robots in the system in a timely and effective manner; the final result can be obtained by simply and quickly processing the data on the robot side, without the need for complex calculations and forwarding by the dispatch center; there is no need to consider the formation transformation logic in various situations, and it can adapt to various complex formation situations and systems with any number of robots.

[0057] The embodiment of the present invention further provides a multi-robot anti-collision system, wherein the system has at least two robots, each of which is equipped with a set of wireless ad hoc network communication devices, and any robot can communicate with all other robots through the wireless ad hoc network communication devices;

[0058] Each robot in the system calculates its own final target speed according to the multi-robot anti-collision method described in the above embodiment, and runs according to its own final target speed.

[0059] The built-in processor of each robot calculates its own target speed, anti-collision speed, advance adjustment speed and final target speed.

[0060] Through the above specific implementations, those skilled in the art can easily implement the present invention. However, it should be understood that the present invention is not limited to the above specific implementations. On the basis of the disclosed implementations, those skilled in the art can arbitrarily combine different technical features to achieve different technical solutions.

[0061] Except for the technical features described in the specification, all other technical features are known technologies to those skilled in the art.

Claims

1. A multi-robot collision avoidance method, characterized in that: For at least two robots, each robot is equipped with a set of wireless ad hoc network communication equipment, which can add all robots in the same working area to the same network, so that any robot in the network can communicate with all other robots, and any robot in the network broadcasts its own speed and position information to other robots; Calculation is performed on the robot side to obtain the robot's own target speed, calculate the anti-collision speed based on the distance from other robots in the network, obtain the target speeds of other robots in the network and determine the adjustment coefficients of each target speed based on their distances to form an adjustment speed; The robot's own target speed, anti-collision speed, and other robots' adjusted speed vectors are added together to calculate the robot's final target speed; Each robot in the network calculates its own final target speed and runs according to its own final target speed; Assume one of the robots is A, and A's own target speed is V1; There are robots B, C, and D within the safe distance of A. The distances between A and B, C, and D are Sab, Sac, and Sad, respectively. Then, according to Sab, Sac, Sad, and the maximum movement speed of robot A, the anti-collision speeds Vab, Vac, and Vad are calculated, respectively, where the magnitudes of Vab, Vac, and Vad are inversely proportional to Sab, Sac, and Sad, respectively; the directions of Vab, Vac, and Vad are from B, C, and D to A, respectively; the vector sum of Vab, Vac, and Vad is calculated, which is the anti-collision speed, represented by V2, and V2=Vab+Vac+Vad; The specific calculation formulas of the anti-collision speed quantities Vab, Vac, and Vad are as follows: Vab=3×Vmax×(S-Sab) / Sab, Vac=3×Vmax×(S-Sac) / Sac, Vad=3×Vmax×(S-Sad) / Sad, Where Vmax is the maximum movement speed that robot A can reach, and S is the safety distance.

2. A multi-robot anti-collision method according to claim 1, characterized in that: A safety distance S is set, that is, when the distance between two robots is greater than S, it is considered that the two robots will not collide; the data of robots greater than the safety distance S are not processed, and for robots within the safety distance, after receiving the position and speed information of other robots, each calculates its final target speed.

3. A multi-robot anti-collision method according to claim 2, characterized in that: The safety distance S is determined according to the maximum moving speed and acceleration of the robot: S=Vmax² / 2a + L, Among them, Vmax is the maximum speed that the robot can reach, a is the maximum acceleration that the robot can reach, and L is the maximum diameter of the robot.

4. A multi-robot anti-collision method according to claim 2 or 3, characterized in that: The current actual moving speeds of robots B, C, and D are Vb, Vc, and Vd respectively. The coefficients of Vb, Vc, and Vd are determined according to Sab, Sac, and Sad. The speed multiplied by its coefficient is its adjustment speed. The sum of the adjustment speeds is called the lead adjustment speed, which is represented by V3. Then the final target speed of robot A is: V=V1+V2+V3.

5. A multi-robot anti-collision method according to claim 4, characterized in that: The advance adjustment speed V3=KbVb+KcVc+KdVd, wherein the magnitudes of coefficients Kb, Kc, and Kd are inversely proportional to Sab, Sac, and Sad, respectively.

6. A multi-robot anti-collision method according to claim 4, characterized in that: The distance between the robot A and robots B, C, and D is a two-dimensional space distance, and each robot sends a two-dimensional coordinate position to other robots in the network; the V1, Vb, Vc, Vd and Vab, Vac, and Vad are all two-dimensional vectors.

7. A multi-robot anti-collision method according to claim 4, characterized in that: The distance between the robot A and robots B, C, and D is the Euclidean distance, and each robot sends a three-dimensional coordinate position to other robots in the network; the V1, Vb, Vc, Vd and Vab, Vac, and Vad are all three-dimensional vectors.

8. A multi-robot anti-collision system, characterized in that: The system has at least two robots, each of which is equipped with a set of wireless ad hoc network communication equipment, through which any robot can communicate with all other robots; Each robot in the system calculates its own final target speed according to the multi-robot collision avoidance method according to any one of claims 1 to 7, and runs according to its own final target speed.

9. A multi-robot anti-collision system according to claim 8, characterized in that: The built-in processor of each robot calculates its own target speed, anti-collision speed, advance adjustment speed and final target speed.

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