Collision-avoidance formation control method and system for mobile robots subject to perturbations and communication limitations

Abstract

A method and system for controlling collision avoidance formation of mobile robots subject to perturbations and communication limitations. [Solution] A formation system model of multiple mobile robots is constructed, the total perturbation is estimated, a reference trajectory of the first virtual leader in the formation of mobile robots is set, a corresponding desired formation is formed based on the set desired distance and desired angle between the robots, distance error and angle error during the formation are created, and the created distance error and angle error are limited so that they are always within the corresponding specified limits using specified performance control technology, and a perturbation suppression formation system controller is constructed using dynamic surface control technology according to the distance error, angle error and estimated total perturbation.

Description

[Technical field]

[0001] The present invention relates to the technical field of mobile robot control, and more particularly to a method and system for controlling a collision avoidance formation of a mobile robot subject to perturbations and communication limitations. [Background technology]

[0002] The description in this section merely provides background information related to the present invention and does not necessarily constitute prior art.

[0003] Robots (e.g., wheeled robots) are widely used in the fields of environmental monitoring, target search, agricultural machinery, mining and military. Robot systems have the advantages of rapid response, high flexibility, high reliability and flexible mechanical structure. Multi-robot cooperative formation control can provide efficiency, fault tolerance and economy that cannot be achieved by a single robot, and can realize efficient cooperative operation on a target. In cooperative formation, multi-robot systems can share environmental perception and single-unit state information, dynamically adjust the formation shape according to the task and external environment constraints, and significantly improve the task completion and execution efficiency. To solve the problem of multi-robot formation control, various control strategies have been adopted, including behavior-based control, virtual structure and leader-follower structure. Among them, the leader-follower formation structure has attracted more attention due to its simplicity and scalability.

[0004] In the actual formation control of multiple mobile robots, it is obviously very important to ensure that the whole system always operates stably. In the actual case, since there are various mobile robots, the model parameters have uncertainty, and various unknown disturbances may be received during the actual formation running. Therefore, it has become particularly important to design a control strategy that can offset these total perturbations, including disturbances and model parameter uncertainties, and minimize the impact on the system. At present, although research on perturbation suppression of a single mobile robot is relatively advanced, the formation control of multiple mobile robots is still mostly stuck on ideal assumptions, and the effects of model uncertainty and disturbances are not taken into account. Therefore, in the present invention, a perturbation estimator is designed to offset the total perturbation, so that the formation control has higher robustness.

[0005] In the formation control, not only is it very important to finally form a stable formation, but it is also necessary to consider the distance and angle between each robot in the process of forming the final formation. If the distance or angle is too large, the communication between the robots may be interrupted or more resources may be required for communication, and if the distance is too small, the robots may collide with each other, and the movement trajectory of the robot may be deviated, and even physical damage may affect the movement. Therefore, in the formation control process, it is very important to set upper and lower limits for the distance and angle between the robots. However, the current formation control of mobile robots rarely takes this into consideration. The present invention adopts a prescribed performance control technology to ensure that the distance and angle between the robots are always within a predetermined allowable range.

[0006] In the design of control strategies for mobile robots, most current research uses the backstepping method. The backstepping method refers to a nonlinear control method designed based on the Lyapunov stability theory. By designing the virtual control input of the system step by step, the Lyapunov function of the system is gradually reduced at each step, and the derivative of the previous step is used to design the control rate of each step, thereby achieving system stability. However, in the case of high-dimensional systems, the problem of differential explosion is likely to occur. Summary of the Invention

[0007] In order to solve the above problems, the present invention provides a method and system for collision avoidance formation control of mobile robots subjected to perturbations and communication limitations. In the present invention, by utilizing a leader-follower structure, prescribed performance control technology and dynamic surface control technology to construct a perturbation estimator, the mobile robots can not only eventually complete formation running even in the presence of perturbations, but also avoid collisions and maintain communication at all times.

[0008] According to some embodiments, the present invention adopts the following technical solutions.

[0009] Building a formation system model of multiple mobile robots, taking into account uncertainties of model parameters and continuous bounded external perturbations; estimating the total perturbation consisting of the uncertainty in the model parameters and the disturbances; Setting a reference trajectory of a first virtual leader in a formation of mobile robots, forming a corresponding desired formation according to the set desired distance and desired angle between the robots, and creating a distance error and an angle error during the formation according to the desired distance and the actual distance, and the desired angle and the actual angle; Using a prescribed performance control technique to restrict the distance error and angle error so that they are always within the corresponding prescribed limits, and using a dynamic surface control technique to construct a perturbation suppression formation system controller according to the distance error, angle error and estimated total perturbation based on the Lyapunov stability theory; performing robot formation control by the formation system controller.

[0010] As an optional embodiment, a specific process of constructing a formation system model of multiple mobile robots includes creating a relationship between the coordinate position of each robot in the formation system of mobile robots, the running angle and angular velocity between the robot and the x-axis direction, and a relationship equation between each perturbation and the mobile robot.

[0011] In an optional embodiment, a total perturbation consisting of uncertainties in the model parameters and external disturbances is estimated based on velocity state information and control input information of the mobile robot.

[0012] As an optional embodiment, the process of forming the corresponding desired formation based on the set desired distance and desired angle between the robots includes: ensuring that each robot i can effectively follow its leader robot through a communication and control strategy between the robots, while maintaining the desired distance and desired angle between the leader and the followers; distance ra i (t) and angle θ i (t) represents the distance and angle between the leader and follower.

[0013] In an alternative embodiment, the specific process for limiting the distance and angle errors created by the prescribed performance control technique is as follows: A collision avoidance condition for each robot is set such that the distance between the leader and the follower is greater than a minimum safe distance; A communication maintenance condition for each robot is set such that the distance between the leader and the follower is smaller than the maximum range in which communication can be maintained; The angle constraint includes setting a maximum angle at which each follower robot can observe its leader using a stationary visual sensor.

[0014] Furthermore, upper and lower limits are set for the distance error and the angle error, respectively, and the formation error is converted into a logarithmic barrier function using a prescribed performance control method.

[0015] In an optional embodiment, the robot is a wheeled mobile robot, and the formation system controller for perturbation suppression comprises:

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[0016] a model building module configured to build a formation system model of the multi-mobile robots, taking into account uncertainties of model parameters and external continuous bounded perturbations; an estimation module arranged to estimate a total perturbation consisting of the uncertainty in the model parameters and the disturbances; an error calculation module configured to set a reference trajectory of a first virtual leader in a formation of the mobile robots, form a corresponding desired formation according to a desired distance and a desired angle between the set robots, and create a distance error and an angle error during the formation according to the desired distance and the actual distance, and the desired angle and the actual angle; a control module arranged to limit the created distance error and angle error so that they are always within corresponding specified limits by a specified performance control technique, to construct a perturbation-suppressing formation system controller by a dynamic surface control technique according to the distance error, the angle error, and the estimated total perturbation based on the Lyapunov stability theory, and to perform robot formation control by the formation system controller.

[0017] A computer-readable storage medium used to store computer instructions that, when executed by a processor, complete the steps in the above method.

[0018] An electronic device comprising a memory, a processor, and computer instructions stored in the memory and executable on the processor, the computer instructions, when executed by the processor, causing the device to complete the steps of the method.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] In a multi-wheeled mobile robot system, the present invention designs a perturbation estimator that can offset perturbations in a control strategy, whereas in conventional studies, perturbations are ignored or the offset effect of perturbations is insufficient.

[0021] In contrast to the fact that most current formation controllers for mobile robots do not take into account distance and angle in the formation formation process, the present invention utilizes specified performance control technology to ensure that the distance and error are always kept within a specified range throughout the entire process, thereby avoiding collisions and maintaining communication.

[0022] The present invention overcomes the deficiencies of the currently used backstepping method by utilizing dynamic surface control techniques and avoids the potential differential explosion problem.

[0023] In order to make the above objects, features and advantages of the present invention clearer and more comprehensible, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] The drawings in the specification which form a part of the present invention are intended to provide a further understanding of the present invention, and the illustrative embodiments of the present invention and the description thereof are intended to interpret the present invention and are not intended to unduly limit the present invention. [Brief description of the drawings]

[0025] [Figure 1] 1 is a flow chart of a method of the present invention. [Diagram 2] FIG. 1 is a schematic diagram of the structure of a wheeled mobile robot. [Diagram 3] This structure consists of a leader robot and a follower robot in the leader-follower formation method. [Figure 4] This is a schematic diagram of the trajectory of a formation system for a wheeled mobile robot over time in the x and y axis directions of the ground coordinate system. [Diagram 5] 13 is a graph of distance error erai in formation control. [Figure 6] 1 is a graph of an angle error eθi in formation control. [Figure 7] This is a comparison diagram of the average error EΛ using the control method of this embodiment and the control method related to the document [1] in formation control. [Figure 8] 1 is a graph of a left wheel control input τDLi and a left wheel control input τDRi. [Figure 9] Estimator state

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[0026] The formation perturbation suppression control method for avoiding collisions between the leader and followers and maintaining communication in a multi-wheeled mobile robot system according to the present invention will be further described with reference to the drawings.

[0027] As shown in Fig. 2, in the formation system of multi-wheeled mobile robots, when there exists uncertainty and disturbance of model parameters, a formation controller is constructed based on the system error and estimated total perturbation by the prescribed performance control technique and the dynamic surface control technique, and each wheeled mobile robot forms a desired formation motion. The method includes the following steps 1 to 5.

[0028] In step 1, considering the influence of nonlinear dynamic system, disturbance, uncertainties of system model parameters and formation control input signals in the Euler-Lagrange system, the following dynamics model of the formation system of multi-wheeled mobile robots is constructed.

[0029]

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[0030] Here, i=1,2,...,N represents the i-th robot in a formation system consisting of N wheeled mobile robots. i =[x i ,y i ,φ i ] T where x i , y i are the x-axis and y-axis position coordinates of the i-th robot in the formation system in the ground coordinate system, respectively, and φ i is the travel angle between the i-th robot in the formation system and the x-axis direction. Vector

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[0031] As shown in Figure 2, G i represents the center of mass of the i-th wheeled mobile robot, and C i represents the geometric center of a wheeled mobile robot. The robot includes a pair of drive wheels, the wheels being spaced apart by 2L i and the radius of each wheel is R i Also, the parameter b i is the geometric center C i From the center of mass G i The system parameter M 1i , M 2i , L i and R i , and the centrifugal and Coriolis coefficients h i and damping coefficient I 1i and I 2i are assumed to be constants for the uncertainties arising from modeling. Here, M ri represents the total mass of the i-th wheeled mobile robot, g is the gravitational acceleration, z1, z2, z3, z4, z5, z6, and z7 are unknown constants representing friction and perturbation coefficients. 1i and dZ 2i constitutes part of the disturbance acting on the i-th robot. The linear velocity of the i-th robot, ν fi and angular velocity νwi , and

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[0032] Therefore, the dynamic model of the wheeled mobile robot can also be expressed by the following relational equation:

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[0033] Wheeled mobile robots have limitations,

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[0034] In this embodiment, there are two predetermined conditions: (1) the acceleration of the wheeled mobile robot;

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[0035] In step 2, a perturbation estimator is designed based on its own speed state information and control input information.

[0036] Configure the filter as follows:

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[0037]

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[0038] It is important to note that the variable γ i is the filter state

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[0039] In step 3, a desired formation is formed based on the desired distance and desired angle between the set robots. A distance error and an angle error during the formation are generated based on the desired distance and the actual distance, and the desired angle and the actual angle. The process includes the following steps S301 and S302.

[0040] In S301, a desired formation of a multi-wheeled mobile robot is constructed.

[0041] The main goal of this embodiment is to formulate a control strategy for each robot in the multi-wheeled mobile robot. Through the communication and control strategy between the robots, we ensure that each robot i can effectively follow its leader robot i-1, while maintaining the desired distance and desired angle between the leader and the follower (i∈{1,2,3,...,n}). The leader of the first robot is a virtual robot, and the specific trajectory is the reference trajectory p0=[x0,y0,φ0]. T The diagram shows the relationship between the leader and the follower during formation. In the following, the distance between the leader and the follower is defined as ra i (t) and angle θ i (t) is defined.

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[0042] However, the following applies:

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[0043] Function θ i (t) is smooth and bounded, with a well-defined solution in the continuous interval (-π,π]. By the definition of atan2(y,x), x i-1 (t)-x i (t)=0 and y i-1 (t)-y i(t)=0 at the same time, ra i It can be seen that atan2(y,x) is indefinite, since (t) is 0. This means that collision avoidance is essential in such formation control. Moreover, such a control method is implemented based on communication between the robots and has specific requirements for the distance between the two robots. Thus, the formation control not only ensures collision avoidance, but also maintains the distance required for communication.

[0044] In S302, the distance error and the angle error in the system are generated.

[0045] The following definitions explain distance error and angle error in formation control.

[0046] e rai (t)=ra i (t)-ra i,de (t) e θi (t)=θ i (t)-θ i,de (t) However, e rai (t) is the distance error, and e θi (t) is the angular error, ra i,de (t) is the desired distance, and θ i,de (t) is the desired angle.

[0047] Step 4: Using the specified performance control technique, the distance error and angle error are limited so that they are always within the specified limits, and using the dynamic surface control technique, the formation system controller with perturbation suppression is designed, which includes the following steps S401, S402 and S403.

[0048] In S401, the distance error and the angle error are limited.

[0049] The collision avoidance condition for robots is ra i (t)>ra i,min (t) where ra i,min (t)(ra i,min(t)>0) represents the minimum safe distance to prevent collisions. The prerequisite for robots to maintain communication is ra i (t) <ra i,max (t) and ra i,max (t)(ra i,max (t)>ra i,min (t)>0) represents the maximum range over which communication can be maintained. In addition to resolving the range constraints, this embodiment also considers angle constraints, |θ i (t)|<θ i,max (t), where θ i,max (t)>0 represents the maximum angle at which a follower robot i in a swarm can observe its leader i-1 with a stationary visual sensor. To prevent the transient performance from exceeding a predefined performance limit, the error e rai (t) and e θi We add constraints to the predefined performance settings of (t). The constraints that the error must satisfy are:

[0050]

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[0051]

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[0052] The designed parameters are

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[0053] In S402, the distance error and the angle error are converted by a specified performance control technique.

[0054] Based on the principle of prescribed performance control theory, the error e during formation Λi (t) is the logarithmic barrier function γ Λi Convert to (t).

[0055]

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[0056] Barrier function γ Λi (t) and formation error e Λi (t) is related to the barrier function γ Λi As (t) approaches zero, the formation error e Λi (t) also approaches zero. γ Λi The derivative of (t) can be expressed as follows:

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[0057] Therefore, γ rai (t) and γ θi The derivative of (t) is:

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[0058] In S403, a controller is designed using dynamic surface control technology.

[0059] Coordinate transformation is introduced. Specifically,

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[0060] Virtual control input δ li , δ 2i is as follows:

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[0061] However, Γ rai and Γ θi are all positive numbers.

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[0062]

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[0063] where the parameter matrix Γ 2i =diag[Γ 21i ,Γ 22i ], where Γ 2li >0.

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[0064] Step 5 performs theoretical verification and simulation verification, and includes the following steps S501 and S502.

[0065] In S501, the theoretical stability of the control method is verified by creating a Lyapunov function using the second Lyapunov method.

[0066] Lyapunov candidate function V i is as follows:

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[0067] Its first derivative can be expressed as follows:

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[0068] However, the following applies:

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[0069] J + (φ i ) is J(φ i ), where

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[0070]

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[0071] therefore,

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[0072] As is evident,

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[0073] therefore,

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[0074] Also, as t approaches infinity, e Λi Since (t) approaches 0, the effectiveness of the controller has been theoretically proven.

[0075] In S502, the present embodiment verifies the invented control method by computer software MATLAB. In the simulation, each step is as follows: 1. and 2.

[0076] 1. The parameters of the four robots in the wheeled mobile robot formation system are selected from Table 1 below. [Table 1]

[0077] Matrix parameters

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[0078] Some of the disturbances experienced by the system are: d 11 =50+cos(0.01t)+14sin(0.02t)-19sin(0.04t)+6cos(0.3t) d 12 =18-sin(0.01t)+14.5cos(0.02t)+11sin(0.06t)+8sin(0.2t) d 21 =26+15cos(0.01t)+13sin(0.02t)-5cos(0.3t) d 22 =12+12cos(0.02t)+12cos(0.06t) d31 =-27-15cos(0.01t)-6cos(0.3t) d 32 =13+25cos(0.02t) d 41 =33-12cos(0.01t)-3sin(0.04t) d 42 =19+14cos(0.08t)-2.5cos(0.3t)

[0079] Parameter z1 represents the coefficient of friction with the ground and changes only with the change in the robot's position. Parameters z2, z3, z4, z5, and z6 represent other friction and disturbance coefficients and change only with time. The values ​​of these parameters are:

[0080] -10m≦x i <80m and -20m≦y i If <40m, z1=0.02, 80m≦x i ≦160m and -20m≦y i If ≦130m, z1=0.05, -10m≦x i <80m and 40m≦y i If ≦130m, z1=0.08.

[0081] When t<50s, z2=1.2, z3=0.7, z4=0.5, z5=0.8, z6=0.4, z7=0.3, When t ≥ 50s, z2=1.8, z3=1.5, z4=1.1, z5=1.6, z6=0.9, z7=0.8.

[0082] In this system, the length of a given robot is 2.5 m, and the safety distance to prevent collision is ra i,min (t) = 3m. In order to maintain communication, the maximum communication range is ra i,max (t) = 5m. The desired distance is ra i,de= 4m, and the maximum allowable angle is θ i,max = 1 rad, and the desired azimuth angle is θ i,de =0 rad.

[0083] Predefined performance functions

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[0084] 2. In this simulation, the reference trajectory p0 of the virtual leader in the formation system of wheeled mobile robots is as follows:

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[0085] However, the time constant t pc is 30s, and t2 is 0.02(tt pc ) is defined as pc If t is smaller than t, then the reference trajectory is a straight line. pc If the distance is greater than 100 m, the trajectory forms a circle with a radius of 60 m.

[0086] The initial position of the virtual leader robot is p0(0) = [0,0,0] T and the initial velocity is ν0(0)=[0,0] T The initial positions of the four robots are as follows:

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[0087] The explanation for the results is as follows:

[0088] As shown in Figure 4, the trajectory of the formation movement of the wheeled mobile robots following the leader is shown. Each different type of figure represents one wheeled mobile robot, and the time arrows represent the positions of all four wheeled mobile robots at a specific time.

[0089] As shown in Fig. 5 and Fig. 6, the distance error e rai and the angular error e θi is always bounded within a given range in the presence of perturbations, allowing the robot to avoid collisions and maintain communication, and all errors approach zero, proving the effectiveness of the control method.

[0090] As shown in Figure 7,

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[0091] Figure 8 shows the control input τ DLi and the control input τ of the left wheel DRi The curve of is shown.

[0092] Figures 9 and 10 show the estimator state

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[0093] Figures 11 to 14 show the total perturbation

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[0094] It will be apparent to one skilled in the art that the present invention may be implemented as a method, a system, or a computer program product. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. The present invention may also take the form of a computer program product executing on one or more computer usable storage media (including, but not limited to, magnetic disk storage devices, CD-ROMs, optical storage devices, etc.) containing computer usable program code.

[0095] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and combinations of flows and / or blocks in the flowcharts and / or block diagrams, can be realized by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, whereby the instructions executed by the processor of the computer or other programmable data processing apparatus create means for realizing the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams.

[0096] These computer program instructions may be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory create an article of manufacture including instruction means for implementing the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams.

[0097] These computer program instructions may be loaded into a computer or other programmable data processing apparatus to cause the computer or other programmable data processing apparatus to perform a series of operational steps to generate a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams.

[0098] The above is merely a preferred embodiment of the present invention, and is not intended to limit the present invention. Those skilled in the art can make various modifications and changes to the present invention. All modifications, equivalent replacements, improvements, etc. made by those skilled in the art without departing from the spirit and principle of the present invention and without requiring creative effort shall be included within the protection scope of the present invention.

Claims

1. Building a formation system model of multiple mobile robots, taking into account uncertainties of model parameters and continuous bounded external perturbations; estimating the total perturbation consisting of the uncertainty in the model parameters and the disturbances; Setting a reference trajectory of a first virtual leader in a formation of mobile robots, forming a corresponding desired formation according to the set desired distance and desired angle between the robots, and creating a distance error and an angle error during the formation according to the desired distance and the actual distance, and the desired angle and the actual angle; Using a prescribed performance control technique to restrict the distance error and angle error so that they are always within the corresponding prescribed limits, and using a dynamic surface control technique to construct a perturbation suppression formation system controller according to the distance error, angle error and estimated total perturbation based on the Lyapunov stability theory; and performing robot formation control by the formation system controller; The robot is a wheeled mobile robot, and the perturbation suppression formation system controller comprises: [74] and However, the matrix [Number 75] and the matrix Γ ２ｉ = diag [Γ ２１ｉ , Γ ２２ｉ ] and Γ ２ｌｉ >0, which is a parameter designed [76] and z σｌｉ >0, l ∈ {1, 2}, φ ｉ is the travel angle between the i-th robot in the formation system and the x-axis direction, [77] Let denote the left and right wheel angular velocities of the i-th wheeled mobile robot, and [78] is an estimate of [79] and the filtering virtual control vector [Number 80] and the virtual control input δ ｉ =[δ １ｉ , δ ２ｉ ] Ｔ and [Number 81] and ν ｆｉ and ν ｗｉ are the linear and angular velocities of the i-th robot, [0082] The distance between the pair of drive wheels is 2L ｉ and the radius of each wheel is R ｉ and S δｉ =[γ ｒａｉ μ ｒａｉ cos(θ), γ θｉ μ θｉ ] Ｔ where the logarithmic barrier function [Number 83] and e Λｉ (t) is the formation error, [Number 84] is the upper limit of [Number 85] is the logarithmic barrier function γ Λｉ (t) is a part of the first derivative of (t), where Λ∈{ra, θ}.

2. The collision avoidance formation control method for mobile robots with perturbation and communication restrictions as described in claim 1, characterized in that the specific process of constructing a formation system model of multiple mobile robots includes creating a relationship between the coordinate position of each robot in the formation system consisting of mobile robots, and the running angle and angular velocity between the robot and the x-axis direction, as well as a relationship between the acceleration of the system and each perturbation and the control input of the left and right wheels.

3. The collision avoidance formation control method for mobile robots subject to perturbations and communication limitations as claimed in claim 1, characterized in that a total perturbation consisting of uncertainties in model parameters and disturbances is estimated based on the speed state information and control input information of the mobile robots.

4. The process of forming the corresponding desired formation according to the set desired distance and desired angle between the robots includes: ensuring that each robot i can effectively follow its leader robot through the communication and control strategy between the robots, and maintaining the desired distance and desired angle between the leader and the followers; distance ra ｉ (t) and angle θ ｉ and expressing by (t) the distance and angle between the leader and the follower.

5. The specific process of limiting the distance error and angle error created by the specified performance control technology is as follows: A collision avoidance condition for each robot is set such that the distance between the leader and the follower is greater than a minimum safe distance; A communication maintenance condition for each robot is set such that the distance between the leader and the follower is smaller than the maximum range in which communication can be maintained; The collision avoidance formation control method for mobile robots subject to perturbations and communication limitations as described in claim 1, characterized in that the angle constraint condition includes setting that the follower robot among each robot can observe its leader at the maximum angle using a stationary visual sensor.

6. The collision avoidance formation control method for mobile robots subject to perturbations and communication limitations as claimed in claim 5, characterized in that an upper and lower limit are set for the distance error and the angle error, respectively, and the formation error is converted into a logarithmic barrier function by a prescribed performance control method.

7. A collision avoidance formation control system for a mobile robot subject to perturbation and communication restrictions, which is applied to the collision avoidance formation control method for a mobile robot subject to perturbation and communication restrictions according to any one of claims 1 to 6, comprising: a model building module configured to build a formation system model of the multi-mobile robots, taking into account uncertainties of model parameters and external continuous bounded perturbations; an estimation module arranged to estimate a total perturbation consisting of the uncertainty in the model parameters and the disturbances; an error calculation module configured to set a reference trajectory of a first virtual leader in a formation of the mobile robots, form a corresponding desired formation according to a desired distance and a desired angle between the set robots, and create a distance error and an angle error during the formation according to the desired distance and the actual distance, and the desired angle and the actual angle; a control module configured to limit the created distance error and angle error so that they are always within corresponding specified limits by a specified performance control technique, to construct a perturbation suppression formation system controller by a dynamic surface control technique according to the distance error, the angle error, and the estimated total perturbation based on the Lyapunov stability theory, and to perform robot formation control by the formation system controller.

8. A computer-readable storage medium, characterized in that it is used for storing computer commands which, when executed by a processor, cause the completion of steps in the method according to any one of claims 1 to 6.

9. 7. An electronic device comprising a memory, a processor, and computer commands stored in the memory and executed on the processor, the computer commands, when executed by the processor, causing the device to complete the steps of the method of any one of claims 1 to 6.

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