Single-robot air pollutant source tracing method based on iSurge algorithm

Abstract

The application discloses a single robot air pollutant tracing method based on an ISurge algorithm. Due to irregular and violent fluctuation of airflow information in a ventilation environment, diffusion and concentration distribution of air pollutants are irregular, so that air pollutant tracing has great challenges. At present, there are mainly fixed sensor network method and robot olfaction method for pollutant tracing, and the latter is widely applied due to its high efficiency and strong adaptability. However, the single robot tracing method is prone to losing a smoke plume in the ventilation environment, and the success rate and search efficiency are low. Therefore, the application comprehensively utilizes concentration information and airflow information, calculates a moving direction through a robot executing the ISurge algorithm, searches for the smoke plume and continuously tracks the smoke plume to approach a pollutant release source, and then the robot confirms whether the source is found through a concentration maximum value method. The ISurge algorithm adopted in the application improves the success rate and efficiency of the robot in the ventilation environment, and effectively avoids the problem of the robot falling into a local optimum.

Description

Technical Field

[0001] This invention relates to the field of environmental safety and robotic detection, and in particular to a single-robot method for tracing the source of air pollutants based on the ISurge algorithm. Background Technology

[0002] With the development of science and technology and the improvement of living standards, people have higher requirements for air quality. On the one hand, air pollution can seriously endanger people's health and safety; on the other hand, air pollution can seriously affect the production and research and development of high-precision materials such as chips and vaccines. Quickly and accurately determining the location of pollution sources is crucial to combating air pollution and is of great significance for protecting people's health and reducing property damage.

[0003] Currently, the main methods used for pollutant source tracing are fixed sensor networks and mobile robot olfactory methods. The former typically uses the pollutant concentration detected by a limited number of sensors to infer the source location. The latter usually uses robots equipped with sensors to autonomously search for target pollutants, track plumes, and ultimately locate the pollution source. Compared to fixed sensor networks, mobile robot olfactory methods do not require pre-deployment of sensors or solving complex pollutant diffusion equations, can be deployed quickly, and are highly adaptable to unknown environments.

[0004] A ventilated environment is one with constantly flowing air. Because ventilation methods are not uniform, typically including mechanical ventilation, natural ventilation, and unidirectional flow ventilation, airflow velocity and direction vary, resulting in different flow fields such as turbulence and eddies. The diffusion and concentration distribution of pollutants become more complex in this environment, increasing the difficulty of robotic source tracing. Furthermore, irregularly diffused plumes are fragmented and dispersed by dynamic airflow, creating multiple localized concentration extremes within the room. Robots can easily become trapped in these localized extremes and struggle to escape, making it difficult to accurately pinpoint the source location.

[0005] Most current single-robot source tracing methods are based on chemotacticity algorithms, wind-oriented algorithms, and biomimetic algorithms. These methods rely primarily on single indicators such as pollutant concentration or airflow information. In ventilated environments, robots are prone to losing plume information or getting stuck in local extremes, resulting in low success rates and efficiency in source tracing. Therefore, this invention, based on the wind-oriented Surge algorithm, introduces concentration information and proposes an ISurge-based source tracing method to improve the performance of single-robot source tracing. Summary of the Invention

[0006] This invention proposes a single-robot air pollutant source tracing method based on the ISurge algorithm, comprising the following steps:

[0007] Step 1: Place the robot in the environment to be tested and start the robot to collect airflow information and target pollutant concentration information in the environment;

[0008] Step 2: The robot executes the ISurge algorithm to calculate the direction of movement based on the collected concentration and airflow information, and continues to move closer to the pollutant release source;

[0009] The robot's direction of movement is equal to the direction of the vector combination of the concentration term direction and the headwind term direction:

[0010]

[0011] Where t is the number of steps the robot moves; Let be the displacement vector of the robot at step t+1; L be the unit step size of the robot; S(t) be the time-averaged concentration value detected by the robot at step t. Let be the concentration term vector of the robot at step t; Let the headwind term be the robot's headwind term at step t.

[0012] After the robot moves t steps to reach a new position, it determines whether the average concentration value detected at the current position is greater than the average concentration value at the previous position. If so, the concentration term vector... The direction is the direction the robot moved in the previous step; if not, the concentration term vector The direction is the opposite of the robot's previous movement direction;

[0013] After the robot moves t steps to reach a new position, the headwind term at step t is calculated.

[0014]

[0015] in, The airflow velocity detected at step t; V max It is the threshold for the robot to measure airflow speed; yes Length; It is a random unit vector.

[0016] The robot moves in the manner described above. If the average concentration of the pollutant detected by the robot during any six consecutive steps remains unchanged, it proceeds to the next step.

[0017] Step 3: The robot determines whether the detected maximum time-averaged concentration value is greater than the threshold S. max If yes, the robot has found the source, ends the tracing process, and outputs the source location; if no, the robot has not found the source and proceeds to step 2.

[0018] The single-robot air pollutant source tracing method based on the ISurge algorithm is characterized in that the time-averaged concentration value is:

[0019]

[0020] Where η is the time-averaged concentration; n is the robot's data collection time; R i It is the instantaneous concentration value collected by the robot at time i.

[0021] The threshold S max Let be the average concentration value collected by M specific gaseous pollutant sensors within T s, wherein the M gaseous pollutant sensors are uniformly placed on a circle with a radius of X m centered on a continuously releasing pollution source.

[0022] The beneficial effects of the above technical solution of the present invention are as follows:

[0023] This invention discloses a single-robot air pollutant tracing method based on the ISurge algorithm. The robot uses the ISurge algorithm to continuously track pollutant plumes. It incorporates concentration information into the original Surge algorithm based on airflow information, which improves the ability of a single robot to continuously track pollutant plumes in complex flow field environments, and greatly enhances the success rate and efficiency of robot tracing. Attached Figure Description

[0024] Figure 1 This is a flowchart of a single-robot air pollutant source tracing method based on the ISurge algorithm disclosed in this invention;

[0025] Figure 2 This is a schematic diagram of robot movement for a single-robot air pollutant tracing method based on the ISurge algorithm disclosed in this invention. Detailed Implementation

[0026] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. The technical problems solved by the present invention and its beneficial effects are also described. It should be noted that the described embodiments are only intended to facilitate understanding of the present invention and do not constitute any limitation thereof.

[0027] The technical problem this invention aims to solve is that existing single-robot source tracing methods suffer from low success rates and low search efficiency in ventilated environments (turbulent flows) where air pollutants are irregularly distributed, fluctuate frequently and violently. Therefore, this invention provides a single-robot air pollutant source tracing method based on the ISurge algorithm. This method comprehensively utilizes target pollutant concentration information and airflow information to search for and continuously track the plume as it approaches the pollutant release source. This improves the ability of a single robot to continuously track pollutant plumes in complex flow field environments, significantly enhancing the success rate and efficiency of robot source tracing. The pollutants described in this invention typically refer to toxic, harmful, flammable, and explosive gaseous substances, volatile substances, semi-volatile substances, and particulate matter, such as carbon monoxide, formaldehyde, CH4, and dust.

[0028] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0029] This embodiment discloses a single-robot air pollutant source tracing method based on the ISurge algorithm, targeting CH4 gas leakage sources in indoor mechanical ventilation environments, such as... Figure 1 As shown, the specific implementation steps are as follows:

[0030] Step 1: Place the robot in the environment to be tested and start the robot to collect airflow information and CH4 gas concentration information in the environment;

[0031] Step 2: The robot executes the ISurge algorithm, such as... Figure 2 As shown, the direction of movement is calculated by collecting CH4 gas concentration information and airflow information, and the system continues to move closer to the pollutant release source.

[0032] The robot's direction of movement is equal to the direction of the vector combination of the concentration term direction and the headwind term direction:

[0033]

[0034] Where t is the number of steps the robot moves; Let be the displacement vector of the robot at step t+1; L be the unit step size of the robot; S(t) be the time-averaged concentration value detected by the robot at step t. Let be the concentration term vector of the robot at step t; Let the headwind term be the robot's headwind term at step t.

[0035] After the robot moves t steps to reach a new position, it determines whether the average concentration value detected at the current position is greater than the average concentration value at the previous position. If so, the concentration term vector... The direction is the direction the robot moved in the previous step; if not, the concentration term vector The direction is the opposite of the robot's previous movement direction;

[0036] After the robot moves t steps to reach a new position, the headwind term at step t is calculated.

[0037]

[0038] in, The airflow velocity detected at step t; V max It is the threshold for the robot to measure airflow speed; yes Length; It is a random unit vector.

[0039] The robot moves in the manner described above. If the average concentration of CH4 detected by the robot in any six consecutive steps does not change, it proceeds to the next step.

[0040] Step 3: The robot determines whether the detected maximum time-averaged concentration value is greater than the threshold S. max If yes, the robot has found the source, ends the tracing process, and outputs the source location; if no, the robot has not found the source and proceeds to step 1.

[0041] When the robot reaches the termination step count N during the tracing process, it exits the tracing process and determines that the tracing has failed.

[0042] The time-averaged concentration value is:

[0043]

[0044] Where η is the time-averaged concentration; n is the robot's data collection time; R i It is the instantaneous concentration value collected by the robot at time i.

[0045] The threshold S max The average concentration value is collected over 300 seconds by eight specific gaseous pollutant sensors, which are evenly placed on a circle with a radius of 0.5 m centered on a continuously releasing pollutant source.

[0046] The beneficial effects of this invention are as follows:

[0047] This invention overcomes the challenges of single-robot source tracing in complex flow fields under ventilated conditions. It solves the problems of single-robot algorithms easily losing plumes and having low success rates and search efficiency in ventilated environments. By comprehensively utilizing the concentration information of air pollutants and airflow information to improve the algorithm, it enhances the robot's ability to track plumes over long distances in complex flow fields under ventilated conditions. At the same time, it greatly avoids the problem of the robot getting stuck in local concentration extreme areas and having difficulty escaping, thereby improving the success rate and positioning efficiency of robot source tracing.

[0048] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. For those skilled in the art, several improvements and modifications can be made without departing from the principles described in the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A single-robot air pollutant source tracing method based on the ISurge algorithm, characterized in that, Includes the following steps: Step 1: Place the robot in the environment to be tested and start the robot to collect airflow information and target pollutant concentration information in the environment; Step 2: The robot executes the ISurge algorithm to calculate the direction of movement based on the collected concentration and airflow information, and continues to move closer to the pollutant release source; The robot's direction of movement is equal to the direction of the vector combination of the concentration term direction and the headwind term direction: Where t is the number of steps the robot moves; Let be the displacement vector of the robot at step t+1; L be the unit step size of the robot; S(t) be the time-averaged concentration value detected by the robot at step t. Let be the concentration term vector of the robot at step t; Let the headwind term be the robot's headwind term at step t. After the robot moves t steps to reach a new position, it determines whether the average concentration value detected at the current position is greater than the average concentration value at the previous position. If so, the concentration term vector... The direction is the direction the robot moved in the previous step; if not, the concentration term vector The direction is the opposite of the robot's previous movement direction; After the robot moves t steps to reach a new position, the headwind term at step t is calculated. in, The airflow velocity detected at step t; V max It is the threshold for the robot to measure airflow speed; yes Length; It is a random unit vector; The robot moves in the manner described above. If the average concentration of the pollutant detected by the robot during any six consecutive steps remains unchanged, it proceeds to the next step. Step 3: The robot determines whether the detected maximum time-averaged concentration value is greater than the threshold S. max If yes, the robot has found the source, ends the tracing process, and outputs the source location; if no, the robot has not found the source and proceeds to step 2.

2. The single-robot air pollutant source tracing method based on the ISurge algorithm according to claim 1, characterized in that, When the robot reaches the termination step count N during the tracing process, it exits the tracing process and determines that the tracing has failed.

3. The single-robot air pollutant source tracing method based on the ISurge algorithm according to claim 1, characterized in that, The time-averaged concentration value is: Where η is the time-averaged concentration; n is the robot's data collection time; R i It is the instantaneous concentration value collected by the robot at time i.

4. The single-robot air pollutant source tracing method based on the ISurge algorithm according to claim 1, characterized in that, The threshold S max Let be the average concentration value collected by M gaseous pollutant sensors within T s, wherein the M gaseous pollutant sensors are uniformly placed on a circle with a radius of X m centered on a continuously releasing pollution source.

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