Personnel emergency evacuation method and system based on improved vector vector diagram

Abstract

The invention discloses a personnel emergency evacuation method and system based on an improved vector vector diagram, and belongs to the technical field of emergency simulation, and the method comprises the steps: carrying out the initialization of an evacuation environment, including the initialization of static environment space elements and the initialization of evacuation crowd individual positions; establishing a visual field containing a plurality of sensing points according to individual positions and speed directions of the evacuated crowd; and for each individual in the evacuated crowd, individual movement is carried out based on the established visual field and through continuous perception of the static environment and interaction among the individuals in the crowd, and crowd evacuation is completed. According to the method and the system, the information exchange among the groups and the perception-feedback process of the crowd to the environment are fully considered in the evacuation simulation process, and the authenticity of the simulation process is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of emergency simulation, and more particularly to a personnel emergency evacuation method and system based on an improved vector diagram. Background Art

[0002] Natural disasters often cause drastic changes in the urban environment, such as damage to infrastructure such as buildings and roads. At this time, in order to save lives and reduce losses, the most effective measure is for people to quickly leave the dangerous environment. However, this process is often difficult to conduct field experiments due to its huge cost and complex operation. Computer simulation, as an efficient and low-cost research method, is of great help to the problem of urban emergency evacuation under natural disasters: such as calculating the evacuation time of the crowd, the number of casualties and evaluating the evacuation process. Some parameters can reveal the nature and key of the evacuation, and the construction of the evacuation model is crucial, which directly affects the accuracy and scientificity of the evacuation simulation.

[0003] At present, the known emergency simulation evacuation models need to establish the movement rules of individuals in the environment, which mainly include three types: cellular automata, social force model and multi-agent system.

[0004] Among them, the cellular automaton discretizes the space into grid cells and realizes movement through different cell states and neighboring conversion rules; the social force model completes the movement by vector superposition of the "force" generated by each element; the multi-agent model sets a series of individual movement rules to ultimately reach the destination. However, most of the above models lack a description of the real evacuation environment, and have not established a good perception-feedback process of the crowd on the environment, and lack definition and description of the entire evacuation process.

[0005] Therefore, how to improve the feedback perception ability of the crowd to the environment in the emergency simulation evacuation model is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0006] In view of this, the present invention provides a personnel emergency evacuation method and system based on an improved vector graph, which is used to improve the feedback perception ability of the crowd to the environment in an emergency simulation evacuation model.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] Firstly, the present invention discloses a personnel emergency evacuation method based on an improved vector diagram, which comprises the following steps:

[0009] Initialize the evacuation environment, including the initialization of static environment space elements and the initialization of individual positions of the evacuees;

[0010] Establish a visual field containing multiple perception points based on the individual positions and speed directions of the evacuated people;

[0011] For each individual in the evacuated crowd, crowd evacuation is completed by individual movement based on the established visual field and through continuous perception of the static environment and interaction between individuals within the group.

[0012] Furthermore, the static environmental space elements include indoor environmental elements and outdoor environmental elements.

[0013] Furthermore, the individual positions of the evacuated people are initialized by the following steps:

[0014] Randomly generate the initial positions of the evacuated individuals in the evacuation grid environment;

[0015] Or, based on crowd distribution information, the initial positions of the evacuated individuals in the evacuation grid environment are obtained.

[0016] Furthermore, a visual field containing multiple perception points is established according to the individual positions and speed directions of the evacuated people, including:

[0017] For each individual in the evacuated crowd, a vector is established with the individual's position as the starting point, and the radius of the visual field is determined according to the length of the individual's line of sight;

[0018] Determine the visual angle of the visual field based on the individual's velocity direction: in represents the movement speed direction of individual i at time t, θ, represents the set visual half-field angle;

[0019] Discretize the visual field and evenly divide the visual angle of the visual field into several sub-directions;

[0020] In each sub-direction, several sensing points are set according to the distance from the starting point.

[0021] Furthermore, the continuous perception of the static environment specifically includes the following steps:

[0022] S31. Determine the travel cost of each individual in the kth direction based on the exit location and static environment space elements in the evacuation environment

[0023]

[0024] Among them, the first part + represents the exit position direction weight of individual i at time t, represents the velocity direction of individual i at time t, is the unit direction of individual i from its current position to the exit position at time t; the second part Represents a sector p K The environmental factor impact value on xy )=Envi(p xy ) represents the position coordinates of the individual in the evacuation grid environment at position (x, y), K o (d w ) represents the weights of perception points at different distances;

[0025] S32. According to the travel cost of each individual in the kth direction Determine the optimal moving direction of the individual after perceiving the static environment at time t:

[0026]

[0027] S33. The optimal moving direction Obj after each individual perceives the static environment at time t i t determines the perception of the static environment:

[0028]

[0029] Where β is the static environment amplitude adjustment coefficient, is the optimal moving direction of individual i after perceiving the static environment at time t, a i is the basic acceleration of individual i.

[0030] Furthermore, in step S31, the exit position direction weight of individual i at time t is Obtained by the following formula:

[0031]

[0032] In the formula, γ represents the adjustment coefficient, It is the angular deviation between the current velocity direction of individual i and the exit direction at time t.

[0033] Furthermore, the interaction between individuals within a group is obtained by constructing an interaction quantity equation between individuals within a group, and the interaction quantity equation between individuals within a group specifically includes the following expression:

[0034]

[0035] where a i is the basic acceleration of individual i, m i is the mass of individual i, Represents the pressure gradient generated by the surrounding individuals for individual i at time t.

[0036] Furthermore, the pressure gradient of individual i at time t due to the surrounding individuals is obtained by the following steps:

[0037]

[0038] Among them, α is the pressure adjustment coefficient; It is called the neighboring group of individual i, which means that at time t, the perception radius r is centered around individual i. p the set of individuals within the scope; Represented as the adjacent group at time t The pressure value exerted by any individual j on individual i; It represents the kernel function that measures the importance or influence of other individuals j in the adjacent group on the central individual i at time t. Represents the kernel function The gradient function of .

[0039] Furthermore, the kernel function Specifically, it is expressed by the following expression:

[0040]

[0041] Where U is the distance variable; r i is the physical radius of individual i; r j is the physical radius of individual j; Represents the center point of individual i and the adjacent groups at time t The distance between the center point of any individual j in the p is the perception radius of individual i.

[0042] Secondly, the present invention also discloses a personnel emergency evacuation system based on an improved vector diagram, comprising:

[0043] Evacuation environment construction module: used for the spatial elements of the evacuation environment and completes the initialization of the evacuation environment, including the initialization of the static environment spatial elements and the initialization of the individual positions of the evacuees;

[0044] A multi-sensing point visual field construction module: used to establish a visual field including multiple sensing points according to the individual positions and speed directions of the evacuated people in the evacuation environment;

[0045] Crowd evacuation model based on perception-feedback: Crowd evacuation is completed by individual movement based on the established visual field and through continuous perception of the static environment and interaction between individuals within the group.

[0046] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a method and system for emergency evacuation of personnel based on an improved vector diagram:

[0047] The present invention first discretizes the evacuation environment to obtain a two-dimensional grid that can reflect the characteristics of the real environment. The personnel aim to reach the evacuation destination, while considering the influence of obstacles and other individuals. With the basic idea of ​​vector graph, the personnel will establish a discrete visual field containing multiple perception points to quickly extract information from the grid environment, and combine the exit position to obtain the travel cost of each sub-direction in the local environment, and preliminarily obtain the optimal movement direction of the personnel at this position. The crowd density related to the distance is obtained based on the perception kernel function of the personnel, and the density gradient is further converted into the pressure effect of other individuals. The above-mentioned optimal movement direction is corrected so that a certain distance is maintained between individuals during the movement process. After the personnel move in the corrected direction, the next step of perception is carried out.

[0048] Through the above method and system, the present invention fully considers the information exchange between groups and the perception-feedback process of the crowd to the environment during the evacuation simulation process, thereby improving the authenticity of the simulation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0050] Figure 1 A schematic diagram of the overall process of the personnel emergency evacuation method based on the improved vector diagram provided by the present invention.

[0051] Figure 2 This is a flow chart for setting the initial state of evacuation provided by the present invention.

[0052] Figure 3 This is an evacuation update flow chart provided by the present invention.

[0053] Figure 4 A schematic diagram of an individual visual field provided by an embodiment of the present invention.

[0054] Figure 5 A schematic diagram of the initial layout of a classroom and the initial positions of students provided in an embodiment of the present invention.

[0055] Figure 6 A schematic diagram of an evacuation grid environment of a classroom constructed according to an embodiment of the present invention.

[0056] Figure 7 A schematic diagram for comparing the simulation results of the present invention and the actual situation of a classroom provided in an embodiment of the present invention.

[0057] Figure 8 The figure is a schematic diagram for comparing the simulation effects of the present invention and other existing simulation methods for a classroom. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] A method for emergency evacuation of personnel based on improved vector diagram Figure 1 As shown, the following steps are included: initializing the evacuation environment, including initializing the static environment space elements and initializing the individual positions of the evacuated people;

[0060] Establish a visual field containing multiple perception points based on the individual positions and speed directions of the evacuated people;

[0061] For each individual in the evacuated crowd, crowd evacuation is completed by individual movement based on the established visual field and through continuous perception of the static environment and interaction between individuals within the group.

[0062] Specifically, the automated modeling of the evacuation environment classifies the spatial elements in the urban environment and maps them onto a two-dimensional grid; then, it describes the movement capabilities of people based on the basic characteristics of the crowd and establishes a visual field; finally, it plans the overall evacuation path in the established evacuation environment, and determines the evacuation destination of each individual based on the initial position distribution of the crowd.

[0063] The present invention as a whole can utilize the crowd evacuation model based on perception-feedback for local path planning of evacuation, including: 1) perception of static environmental information 2) interaction between individuals within the group;

[0064] Based on the initial environmental information, a grid environment for evacuation simulation is constructed, and the initial position of the crowd is generated; the overall direction of crowd evacuation is calculated to ensure that the evacuation path is reasonable; the crowd's response to environmental changes is simulated by combining the perception-feedback model to guide the crowd to complete the movement. This process realizes the simulation of the entire process from establishing the evacuation environment to the movement of the crowd, ensuring the efficiency and safety of the evacuation process.

[0065] The automatic modeling of the evacuation environment in the present invention includes:

[0066] Key elements are extracted based on the main environmental information of the city, including roads, buildings, obstacles, etc.; the impact of spatial elements on the evacuation process is analyzed in detail and classified, and finally mapped to a two-dimensional grid to establish a two-dimensional grid environment for evacuation.

[0067] The main reason for classification is that various elements in the environment have different effects on evacuation. For example, roads and open spaces are the main routes for evacuation. They are conducive to evacuation and the degree of their benefit to evacuation is different. For example, the wider the road, the more conducive it is to evacuation. However, buildings, rivers, tables and chairs hinder evacuation, and people need to take detours. Moreover, the degree of obstruction of these elements to evacuation is different. The classified elements are stored in the raster environment with different values ​​for distinction.

[0068] The grid stores basic information about environmental elements, and its accuracy can be controlled by the grid size. It can effectively construct the evacuation environment at both micro and macro scales, laying the environmental foundation for the subsequent evacuation process, and is also an important manifestation of the versatility of the model.

[0069] The basic characteristics of the crowd in the present invention are constructed, wherein inherent attributes include people, mass, speed range, etc., which mainly affect the individual's movement ability; and the visual field is the main way of the perception process, and its role is to input environmental information.

[0070] The establishment of the individual visual field in the crowd in the present invention mainly includes determining the main direction of the viewing angle according to the speed direction, and its size is 2θ=180°; determining the radius of the visual field according to the line of sight length, and the visual radius will be adjusted according to the spatial scale.

[0071] The overall path planning described in the present invention mainly determines the main evacuation direction and destination of each individual in the group based on the established environment and the location of the evacuation destination. This process is carried out according to the distance law. The destination, as the end point of the entire evacuation, will play a role in the entire movement process of the individual.

[0072] The perception process in the present invention not only considers the influence of the static environment, but also considers other moving individuals, making the perception process more real and comprehensive. The destination is the end point of the entire feedback mode, while local route planning and speed adjustment constitute the main process, which can be described as:

[0073] M=L(D,E,C)

[0074] Where M represents the local movement (Movement) during the evacuation process, L represents the perception-feedback rule (Law), D represents the evacuation destination (Destination), and E represents the evacuation local environment information (Environment). In the above perception-feedback process, the evacuation local environment information E and the evacuation destination D have been set in advance, and the basic characteristics of the crowd C include the above-mentioned motion attributes and visual field. Under the perception-feedback rule L, the local movement M of the evacuation is completed.

[0075] The local environment information E includes 1) static environment information, which mainly includes information such as buildings, roads, obstacles, etc. stored in the grid environment, and 2) dynamic environment information, that is, other moving individuals around. Individuals complete the corresponding speed adjustment in the local perception process to reasonably respond to the local environment during the evacuation process.

[0076] The influence of the static environment mainly comes from the influence of obstacles and roads on the overall route. This part of information is stored in the grid environment. The perception points in each direction of the individual visual field extract the values ​​in the corresponding grid environment and evaluate each direction to adjust the speed direction.

[0077] The role of the dynamic environment is the interaction between individuals during movement. Here we establish a corresponding smooth kernel function to calculate the crowd density value at each individual position, and then convert the density gradient into a pressure gradient. The acceleration generated by the pressure gradient continuously adjusts the individual speed.

[0078] The environmental modeling method of the embodiment of the present invention is used to construct a grid environment for evacuation. The influence of various spatial elements such as roads, buildings, obstacles, etc. on the evacuation process will be analyzed in detail, and then classified and mapped to the classic two-dimensional grid. The environmental accuracy can be achieved through the grid size to effectively construct the evacuation environment at the micro and macro scales. The evacuation environment shows good versatility. Such a concentrated description and abstract expression is necessary, which simplifies the difficulty of establishing the spatial model, and the subsequent perception-feedback is also established in this process.

[0079] The process of setting the initial state of crowd evacuation is as follows: Figure 2 As shown, the following steps are included:

[0080] Automated modeling of evacuation environments classifies and processes spatial elements in urban environments and maps them onto a two-dimensional grid;

[0081] Describe the movement capabilities of people based on the basic characteristics of the crowd and establish a visual field;

[0082] The overall evacuation route is planned based on the established evacuation grid environment, and the evacuation destination of each individual is determined based on the initial location distribution of the crowd;

[0083] The crowd evacuation model based on perception-feedback is used for local path planning of evacuation, including: 1) perception of static environmental information 2) interaction between individuals within the group.

[0084] Based on the initial environmental information, a grid environment for evacuation simulation is constructed, and the initial position of the crowd is generated. The overall direction of crowd evacuation is calculated to ensure that the evacuation path is reasonable. By combining the perception-feedback model to simulate the response of the crowd to environmental changes, the crowd is guided to complete the movement. This process realizes the simulation of the entire process from establishing the evacuation environment to the movement of the crowd, ensuring the efficiency and safety of the evacuation process.

[0085] In one embodiment of the present application, after the environmental elements are classified and processed, a raster environment is generated through mapping. Examples of the values ​​of this mapping rule are shown in Table 1 and Table 2. By querying Table 1, the values ​​of indoor environmental elements are obtained, and by querying Table 2, the values ​​of outdoor environmental elements are obtained.

[0086] Table-1:

[0087] type Value Example boundary 1 wall exit -1 Door obstacle 1 Furniture, counters the way -1 aisle other 0 Useless space

[0088] Table-2:

[0089] type Value Example Safe Area -10 Parks and playgrounds obstacle high Buildings, lakes the way -width Urban roads of all levels other 0 Other Spaces

[0090] The value of environmental factors is necessary in the subsequent environmental perception process. The individual perception point eventually falls on the grid environment, and environmental information is obtained quickly and efficiently to evaluate the travel cost in that direction. This process is inseparable from the above-mentioned classification of environmental factors. Environmental information is the basis for measuring the travel cost in each direction.

[0091] In one embodiment of the present application, the basic characteristic information of the population and its values ​​are shown in Table 3.

[0092] Table-3:

[0093]

[0094] The mass here is given as the general weight of an adult male, 70kg, and other values ​​can also be taken. The basic acceleration can also be adjusted. The physical radius of a person can be 0.3m, and the perception radius can be 2.0m. Such a large value is in line with the actual situation and can achieve better results in the simulation. The pressure adjustment coefficient α adjusts the strength of the interaction between individuals in the crowd, and the static environment amplitude adjustment coefficient β represents the impact of the static environment on the movement of individuals. The sum of the two is 1. Under normal circumstances, the values ​​of both are 0.5, which means that the influence of environmental factors and surrounding individual factors is considered simultaneously and equivalently. If the stimulus effect of the environment is stronger than that of the surrounding people, the environmental influence is dominant, and the value of β can be increased while the value of α can be reduced.

[0095] Obtain the distribution of the crowd, initialize the individual positions, and then establish the visual field of each individual.

[0096] In the absence of basic distribution information of the crowd, the initial position of the people in the environment is randomly generated; in the case of distribution information, the initial position of the crowd is directly read based on the distribution information.

[0097] The visual field is established based on the position and velocity direction of each individual. The direction of the visual field is determined by the velocity direction, and the size is 2θ = 180°. Combined with the velocity direction, the viewing angle direction is The visual radius (line of sight length) of the visual field is related to the individual's environment. In an indoor environment, the line of sight length L In =4 meters, while in outdoor environment L Out =8 meters.

[0098] The individual visual field established is Figure 4 As shown, there are two obstacles Barrier1 and Barrier2 in the environment, and the position of individual i at time t The speed direction is The viewing angle is 2θ and the viewing angle range is For the exit direction, three sensing points are set in each sub-direction in the figure (indicated by the black dots in the figure). Then, through the selection and determination of the evacuation destination, global path planning is performed: global path planning mainly refers to individual i locking the evacuation destination according to the principle of the closest distance. At time t, each individual i has a clear exit location destination direction and moves in this direction with a certain acceleration. The overall evacuation process is as follows Figure 3 shown.

[0099] The exit location destination direction can be expressed as:

[0100]

[0101] in is the position of individual i at time t, E i is the location of the target point, is the vector difference between the two, is the modulus in this direction, so In fact, it is the unit direction of individual i from its current position to the exit position at time t.

[0102] The maximum acceleration of an individual in the present invention is obtained by superimposing the speed perception of the static environment and the interaction between individuals in the group: in represents the speed perception of individual i in the static environment at time t, It represents the amount of interaction between individuals in the group at time t.

[0103] In this embodiment, the speed perception amount in a static environment is represented by a traffic cost. The process of obtaining the speed perception amount in a static environment by using the traffic cost is described in detail below.

[0104] First, the travel cost of individual i in the kth direction at time t in the individual visual field is determined by the exit position and environmental factors: It can be specifically expressed by the following formula:

[0105]

[0106] In the traffic cost formula, the first part represents the exit direction weight, and the second part represents a sector p K The environmental factors above affect the value. The following is a detailed description of the two parts of the toll.

[0107] The first part of the travel cost, the exit direction weight, can be expressed by the following expression:

[0108]

[0109] In the formula, the γ adjustment coefficient can be taken as 2 in practice; is the velocity direction of individual i at time t and individual i points from its current position to the exit position at time t The angle deviation measures the angle difference between each sub-direction of individual i and the exit direction at different times. The smaller the difference, the smaller the travel cost.

[0110] The angle deviation can be obtained by the following numerical formula. In this method, the visual field needs to be discretized, and the complete visual field is discretized into multiple different sub-directions, and each sub-direction is numbered. For example, in a specific embodiment, 15° can be used as a sub-direction, and the sub-directions are numbered in a counterclockwise direction. At this time, the entire circumference has 24 sub-directions, and the viewing angle occupies 12 sub-directions. In the kth direction (1≤k≤12), m perception points distributed from near to far are set. At each position, the individual forms a complete visual field through 12×m perception points. The angular deviation between k1 and k2 in any two directions is denoted by L P (k1, k2) = |Num(k1) - Num(k2)|, where Num(k1) and Num(k2) are two numbers in the counterclockwise direction among the 24 directions.

[0111] From this we can see that the speed direction of individual i at time t is and individual i points from its current position to the exit position at time t Angular deviation It can be expressed as:

[0112]

[0113] Num() represents the direction number. The visual field is discretized, with 15° as a sub-direction. The sub-directions are numbered in a counterclockwise direction. There are 24 sub-directions in the entire circumference, and the viewing angle occupies 12 sub-directions. In the kth direction (1≤k≤12), m perception points distributed from near to far are set. At each position, the individual forms a complete visual field through 12×m perception points.

[0114] In angle deviation middle, is the velocity direction of individual i at time t, It is the unit direction of individual i from its current position to the exit position at time t; It can be understood as is the position of individual i at time t, E i is the location of the target point, is the vector difference between the two, For this direction.

[0115] The second part of the pass price is a sector p K The environmental factors on the value can be expressed by the following expression:

[0116]

[0117] Where H(p xy )=Envi(p xy ) represents the environmental grid value of the individual at the position (x, y) in the evacuation grid environment. The environmental grid is obtained by mapping the environmental elements. o (d w ) represents the weights of perception points at different distances, and represents the weights of perception points at different distances. The closer the perception point is to the center of individual i, the greater the weight.

[0118] When in an indoor environment,

[0119] When in an outdoor environment,

[0120] d w represents the distance from the perception point at different distances w to the center of individual i; r i Represents the physical radius of individual i. A fixed perception distance d is set in each direction w, describing the distance from the perception point to the individual center (after the perception radius is determined, multiple perception distances can be set in each direction to form a series of perception points, but these distances cannot be greater than the perception radius. Some reference values ​​are given below). For indoor environments, this setting reference value is d w (1≤w≤6)∈{0.5,0.8,1.2,1.8,2.4,3.6}(unit: m), the reference value for outdoor environment is d w (1≤w≤8)∈{0.5,0.8,1.2,2.4,3.6,4.8,6.4,7.2}(unit: m).

[0121] L In It represents the indoor sight length of individual i, usually L In =4m; L Out It represents the outdoor sight length of individual i, usually L Out =8 meters.

[0122] After obtaining the travel costs of individual i in all directions at time t, the optimal moving direction of individual i after static environment perception at time t is determined according to the travel costs.

[0123]

[0124] According to the optimal moving direction of individual i The speed perception of individual i in the static environment can be obtained. It can be obtained by the following formula:

[0125]

[0126] Where, β is the static environment amplitude adjustment coefficient, which can be taken as β = 0.5; a i Expressed as the basic acceleration of individual i.

[0127] According to the above content, the speed perception of the static environment can reflect the relevant influence of individual i in avoiding obstacles in the environment and approaching the destination and exit as quickly as possible.

[0128] In the personnel emergency evacuation simulation, after considering the impact of individuals on the static environment, it is also necessary to consider the interaction between individuals within the group. Specifically, in the embodiment of the present invention, the interaction between individuals within the group It is expressed by the following formula:

[0129]

[0130] where a i is the basic acceleration of individual i, m iis the mass of individual i, Represents the pressure gradient generated by the surrounding individuals for individual i at time t.

[0131] In the embodiment of the present invention It can be obtained by the following formula:

[0132]

[0133] Wherein, α is the pressure adjustment coefficient, which can be specifically taken as α=0.5; It is called the neighboring group of individual i, which means that at time t, the perception radius r is centered around individual i. p The set of individuals within the range, the individuals in this neighboring group have different distances from i, and their influence is also different. Represented as the adjacent group at time t The pressure value exerted by any individual j on individual i, specifically, the pressure value It can be directly measured by the density difference between individuals based on distance weights: in, and They represent the density values ​​of individual i and any individual j based on the distance weight at time t respectively. It represents the kernel function that measures the importance or influence of other individuals j in the adjacent group on the central individual i at time t. Represents the kernel function The gradient function of .

[0134] In the present invention, the density value of individual i based on the distance weight Calculated by the following formula:

[0135]

[0136] Where m j For neighboring groups The mass of any individual j in Represents the kernel function that measures the importance or influence of other individuals j in the adjacent group on the central individual i at time t.

[0137] Specific kernel function It can be expressed as follows:

[0138]

[0139] In the kernel function Where U is the distance variable; r i is the physical radius of individual i; +r j is the physical radius of individual j; Represents the center point of individual i and the adjacent groups at time t The distance between the center point of any individual j in the p is the perception radius of individual i.

[0140] The distance variable U is defined as:

[0141]

[0142] in, Represents the absolute distance between individuals i and j; Rst ij =r p -(r i +r j ) represents the absolute perception radius between individuals i and j.

[0143] From the above kernel function, we can see that when individuals i and j are not within the scope of action, the kernel function when When d , the absolute distance between individuals i and j is less than or equal to 0, and the two individuals will cause a collision effect. ij ≤r ij When U∈[0,r p / (r p -r i -r j )).

[0144] According to the kernel function The expression of for:

[0145]

[0146] Similarly, based on the above density value of individual i based on distance weight It can be seen that for any individual j at time t, the density value based on the distance weight is -Calculated by the following formula:

[0147]

[0148] It should be understood that at this time represents the neighboring group of individual j at time t, m j is the mass of individual j, Represents the center point of individual j and the adjacent groups at time t The distance to the center point of any individual i in .

[0149] because, The influence of surrounding individuals on individual i can be directly converted into acceleration, which in turn affects its subsequent movement direction. Therefore, the interaction between individuals within the group can be expressed as:

[0150]

[0151] The final acceleration is obtained by superimposing the speed perception of the static environment and the interaction between individuals within the group: Individual i completes the evacuation process according to the final acceleration and direction.

[0152] Finally, determine whether the people in the current evacuation space have been evacuated, including:

[0153] For each individual in the evacuation space, check whether it has reached the evacuation exit area;

[0154] If the individual has reached the exit area, they are considered to have evacuated and removed from the current evacuation space;

[0155] When all individuals in the evacuation space have been judged to have been evacuated and moved out of the current space, further evacuation judgment of the space is stopped, and it is determined that the evacuation of the crowd in the evacuation space has been completed.

[0156] The effectiveness of the present invention is illustrated by a specific case.

[0157] In a certain earthquake, the evacuation of 70 students in a primary school classroom was fully recorded. The initial positions of the students were the seats in the classroom. The indoor space size was 6.6 meters × 8.8 meters. The classroom had a 1-meter-wide front door exit. The seven rows of desks and chairs in the classroom can be regarded as simple obstacles. First, let's restore the layout and evacuation simulation of the classroom. The accuracy of the grid environment is 0.1m. The initial layout of the classroom and the initial positions of the students are as follows: Figure 5 As shown, the evacuation grid environment is Figure 6 shown.

[0158] Because the objects to be evacuated are primary school students, we set the individual radius to 0.2m. In a crowded and chaotic environment, the individual perception radius will be smaller. The basic density sensing radius is set to 1m, and the pressure coefficient is 0.6. Because obstacles such as tables and chairs are densely distributed, four fixed values ​​of 0.3m, 0.6m, 0.8m, and 1.2m are set within the perception range to simulate the evacuation. The comparison between the simulation results of this method and the actual situation is shown in the figure below. Figure 7 As shown in the figure. The comparison of simulation results shows that during the evacuation process, people can avoid obstacles such as tables and chairs and choose the most familiar conventional channels to move to the exit. There are some slight squeezing and collision phenomena in this process. By comparison, the simulation path is consistent with the actual path. However, due to the overcrowding of tables and chairs in the classroom, some people move slowly, which leads to differences between the simulation and the actual situation in the later stage of the evacuation.

[0159] The present invention and other methods, such as the multi-agent model (ABM), the social force model (SF) and the cellular automation (CA), are used to perform simulations. The comparison of several results is shown in Figure 2. Figure 8 As shown in the figure. From the perspective of the overall evacuation time, the model (ABM+VFH) adopted by the present invention is closer to the actual result (about 36 seconds), while other models take longer. The real evacuation video shows that students did not start evacuating at the same time. Some students started evacuating slowly because they were organizing their personal belongings or had a long reaction time.

[0160] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0161] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A personnel emergency evacuation method based on improved vector diagram, characterized in that: The following steps are involved: Initialize the evacuation environment, including the initialization of static environment space elements and the initialization of individual positions of the evacuees; Establish a visual field containing multiple perception points based on the individual positions and speed directions of the evacuated people; For each individual in the evacuated crowd, crowd evacuation is completed by individual movement based on the established visual field and through continuous perception of the static environment and interaction between individuals within the group.

2. A personnel emergency evacuation method based on improved vector diagram according to claim 1, characterized in that: The static environmental space elements include indoor environmental elements and outdoor environmental elements.

3. The method for emergency evacuation of personnel based on improved vector diagram according to claim 1, characterized in that: The individual positions of the evacuees are initialized by the following steps: Randomly generate the initial positions of the evacuated individuals in the evacuation grid environment; Or, based on crowd distribution information, the initial positions of the evacuated individuals in the evacuation grid environment are obtained.

4. The method for emergency evacuation of personnel based on improved vector diagram according to claim 1, characterized in that: According to the individual positions and speed directions of the evacuated people, a visual field containing multiple perception points is established, including: For each individual in the evacuated crowd, a vector is established with the individual's position as the starting point, and the radius of the visual field is determined according to the length of the individual's line of sight; Determine the visual angle of the visual field based on the individual's velocity direction: in represents the movement speed direction of individual i at time t, θ, represents the set visual half-field angle; Discretize the visual field and evenly divide the visual angle of the visual field into several sub-directions; In each sub-direction, several sensing points are set according to the distance from the starting point.

5. The method for emergency evacuation of personnel based on improved vector diagram according to claim 1, characterized in that: The continuous perception of the static environment includes the following steps: S31. Determine the travel cost of each individual in the kth direction based on the exit location and static environment space elements in the evacuation environment Among them, the first part represents the exit position direction weight of individual i at time t, represents the velocity direction of individual i at time t, is the unit direction of individual i from its current position to the exit position at time t; the second part Represents a sector p K The impact value of environmental factors on xy )=Envi(p xy ) represents the position coordinates of the individual in the evacuation grid environment at position (x, y), K o (d w ) represents the weights of perception points at different distances; S32. According to the travel cost of each individual in the kth direction Determine the optimal moving direction of the individual after perceiving the static environment at time t: S33. The optimal moving direction after each individual perceives the static environment at time t Determine the perceived amount of a static environment: Where β is the static environment amplitude adjustment coefficient, is the optimal moving direction of individual i after perceiving the static environment at time t, a i is the basic acceleration of individual i.

6. A personnel emergency evacuation method based on improved vector graph according to claim 5, characterized in that: In step S31, the exit position direction weight of individual i at time t is Obtained by the following formula: In the formula, γ represents the adjustment coefficient, It is the angular deviation between the current velocity direction of individual i and the exit direction at time t.

7. The method for emergency evacuation of personnel based on improved vector diagram according to claim 1, characterized in that: The interaction between individuals within a group is obtained by constructing an interaction quantity equation between individuals within a group. The interaction quantity equation between individuals within a group specifically includes the following expression: where a i is the basic acceleration of individual i, m i is the mass of individual i, Represents the pressure gradient generated by the surrounding individuals for individual i at time t.

8. The method for emergency evacuation of personnel based on improved vector diagram according to claim 7, characterized in that: The pressure gradient generated by the surrounding individuals at time t for individual i is obtained by the following steps: Among them, α is the pressure adjustment coefficient; It is called the neighboring group of individual i, which means that at time t, the perception radius r is centered around individual i. p the set of individuals within the scope; Represented as the adjacent group at time t The pressure value exerted by any individual j on individual i; It represents the kernel function that measures the importance or influence of other individuals j in the adjacent group on the central individual i at time t. Represents the kernel function The gradient function of .

9. A personnel emergency evacuation method based on improved vector diagram according to claim 8, characterized in that: The kernel function Specifically, it is expressed by the following expression: Where U is the distance variable; r i is the physical radius of individual i; r j is the physical radius of individual j; Represents the center point of individual i and the adjacent groups at time t The distance between the center point of any individual j in the p is the perception radius of individual i.

10. A personnel emergency evacuation system based on improved vector diagram, characterized in that: include, Evacuation environment construction module: used for the spatial elements of the evacuation environment and completes the initialization of the evacuation environment, including the initialization of the static environment spatial elements and the initialization of the individual positions of the evacuees; A multi-sensing point visual field construction module: used to establish a visual field including multiple sensing points according to the individual positions and speed directions of the evacuated people in the evacuation environment; Crowd evacuation model based on perception-feedback: Crowd evacuation is completed by individual movement based on the established visual field and through continuous perception of the static environment and interaction between individuals within the group.

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