Data-driven double-event-triggered unmanned ship course control method and device

Abstract

The invention relates to the field of artificial intelligence and automatic control, in particular to a data-driven double-event-triggered unmanned ship course control method and device. The method includes: acquiring course angle errors of the unmanned ship at various moments; establishing a nonlinear terminal sliding mode surface function and a second-order discrete sliding mode function according to the course angle error of the unmanned ship; designing an equivalent increment control equation and a switching control equation, and constructing a control model of an unmanned ship controller; inputting the course angle error of the unmanned ship at the current moment into a controller, and outputting a control signal at the current moment; determining a target control signal at the current moment according to a designed input trigger condition and transmitting the target control signal to an actuator; the actuator regulates the course of the unmanned ship according to the target control signal at the current moment; calculating an output course angle at the current moment and sending the output course angle to a sensor; determining a target output signal at the current moment according to a designed output triggering condition and transmitting the target output signal to a controller; and the steps are cycled, and accurate control over the course of the unmanned ship is achieved within the operation time.

Description

Technical Field

[0001] The present invention relates to the field of artificial intelligence and automatic control technology, and in particular to a data-driven dual-event triggered unmanned boat heading control method and device. Background Art

[0002] Driven by the trend of increasing attention to the exploration and development of marine resources, unmanned vehicles (USVs) have been widely developed and applied in recent years. USVs are equipped with autonomous planning and navigation capabilities, and can perform tasks such as patrolling, surveillance, reconnaissance and environmental monitoring, improve the safety and efficiency of water missions, and reduce manpower costs and risks. These capabilities have attracted great attention from researchers.

[0003] For USVs, heading control is a crucial issue. Accurate heading control can enable ships to perform various tasks safely and effectively. However, at different speeds, the hydrodynamic coefficients change significantly due to changes in the wetted surface area, draft and other physical parameters of the hull, making it difficult to obtain an accurate model and thus difficult to accurately control the heading of the ship.

[0004] In the prior art, most of the control methods for unmanned boats are to first establish an initial model of the surface ship, and then design a control system to complete the heading control of the surface ship. However, this method requires continuous identification of the model and the control effect is poor, resulting in a waste of time and computing power. Alternatively, a single model-free adaptive control method is used for heading control. However, a single model-free adaptive control may be sensitive to external interference, noise, and measurement errors, thereby affecting the control performance of the unmanned boat and failing to fully meet the robustness and accuracy requirements of USVs. At the same time, in practical applications, energy consumption is also equally important. Considering the limited bandwidth of maritime communications, communication resources are often limited. In order to ensure that the system can still operate normally within the limited bandwidth, the heading control of unmanned boats that reduces the burden of signal transmission and saves communication resources is more meaningful in navigation practice.

[0005] In summary, the problems in the existing technology that it is difficult to obtain an accurate model of the unmanned boat and thus difficult to perform accurate heading control and that communication resources are often limited need to be solved urgently. Summary of the invention

[0006] To this end, the technical problem to be solved by the present invention is to overcome the problem in the prior art that it is difficult to obtain the precise model of the unmanned boat for precise heading control, and the communication resources are limited.

[0007] In order to solve the above technical problems, the present invention provides a data-driven dual-event triggered unmanned boat heading control method, comprising the following steps:

[0008] Obtain the actual heading angle and expected heading angle of the unmanned boat at each moment, and obtain the heading angle error of the unmanned boat at each moment;

[0009] A nonlinear terminal sliding surface function is established according to the heading angle error of the unmanned boat, and a second-order discrete sliding function is established according to the nonlinear terminal sliding surface function; based on the nonlinear terminal sliding surface function and the second-order discrete sliding function, an equivalent incremental control equation and a switching control equation are designed and a control model of the controller of the unmanned boat is constructed;

[0010] Inputting the heading angle error of the unmanned boat at the current moment and the previous moment into the controller of the unmanned boat, and outputting the control signal at the current moment;

[0011] Based on the target control signal at the last input trigger moment, determine whether the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition; if so, set the current moment as the current input trigger moment, and send the control signal at the current moment as the target control signal at the current input trigger moment to the actuator; if not, send the target control signal at the last input trigger moment as the target control signal at the current input trigger moment to the actuator;

[0012] The actuator adjusts and controls the heading of the unmanned boat according to the target control signal received at the current moment; calculates the output heading angle at the current moment according to the target control signal at the current moment and sends it to the sensor;

[0013] Based on the target output signal at the last output trigger moment, determine whether the difference between the output heading angle at the current moment and the output heading angle at the last output trigger moment meets the output trigger condition; if so, set the current moment as the current output trigger moment, and send the output heading angle at the current moment to the controller of the unmanned boat as the target output signal at the current output trigger moment; if not, send the output heading angle at the last output trigger moment as the target output signal at the current output trigger moment to the controller of the unmanned boat;

[0014] At the same time, when the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition, the pseudo partial derivative in the equivalent incremental input control equation and the switching control equation is updated according to the target control signal at the current input trigger moment, the target output signal at the current output trigger moment, and the pseudo partial derivative value at the previous input trigger moment, and transmitted to the controller of the unmanned boat; when the sum of the equivalent incremental control value and the switching control value at the current moment does not meet the input trigger condition, the pseudo partial derivative value at the previous input trigger moment is transmitted to the controller of the unmanned boat;

[0015] The above steps are iterated repeatedly until the preset running time is reached, and the heading control of the unmanned boat is ended.

[0016] Preferably, the heading angle error of the unmanned boat is expressed as follows:

[0017] E(k)=y d (k)-y(k)

[0018] Among them, y d y(k) represents the expected heading angle at the current moment k, and y(k) represents the actual heading angle at the current moment k.

[0019] Preferably, the nonlinear terminal sliding surface function is expressed as follows:

[0020] s(k)=E(k)+α 1 E(k-1)+α 2 sig γ (E(k-1))

[0021] Among them, sig γ (E(k))=|E(k)| γ sgn(E(k)), sgn() is the sign function; α 1 , α 2 , γ are constant parameters, satisfying 0<α 1 <1、0<α 2 <1, 0<γ<1;

[0022] The second-order discrete sliding mode function is expressed as follows, where -1<β<0 represents the design parameter:

[0023]

[0024] Preferably, the equivalent increment control equation is expressed as follows:

[0025]

[0026] Among them, Δu eq (k) represents the equivalent incremental control value, represents the pseudo partial derivative The estimated value of represents the pseudo partial derivative, σ represents a design constant; d(k) represents the interference value k receives at the current moment, Δd(k) = d(k) - d(k-1);

[0027] The switching control equation is expressed as follows:

[0028]

[0029] Among them, Δu sw (k) represents the switching control value, λ sand q are constant parameters, satisfying the following conditionλ s >D, 0<q<1, D represents a positive real number.

[0030] Preferably, the control model of the controller of the unmanned boat is expressed as follows:

[0031] u(k)=u(k-1)+Δu eq (k)+Δu sw (k)

[0032] Among them, u(k) represents the control signal of the unmanned boat at the current moment, Δu eq (k) represents the equivalent incremental control value at the current moment, Δu sw (k) represents the switching control value at the current moment.

[0033] Preferably, the input trigger condition includes:

[0034] Define k r (r=1,2,...,) is the input trigger time that satisfies the input trigger condition; r represents the number of successful triggering of the input trigger condition, and the input trigger time k that satisfies the input trigger condition is designed. r (r=1,2,...,) as follows:

[0035]

[0036] Among them, z 1 (k) = Δu eq (k)+Δu sw (k); when z 1 (k) greater than When , it is successfully triggered; represents a positive constant, δ represents a constant parameter, satisfying 0<δ<1;

[0037] Combined with the input trigger condition, the control signal at the current moment can be expressed as:

[0038]

[0039] Preferably, the output heading angle at the current moment is expressed as follows:

[0040]

[0041] y(k+1)=F(k+1)+G 1 I(k+1)

[0042] Among them, F(k), I(k), u(k) represent the heading angle, angular velocity, and rudder angle of the current moment k, respectively. O and T represent the maneuvering coefficient. T s represents the sampling time, G1 >0 indicates angular velocity feedback gain.

[0043] Preferably, the output triggering condition includes:

[0044] Define k c (c=1,2,...,) is the output trigger time that meets the output trigger condition; c represents the number of successful triggering of the output trigger condition, and the output trigger time k that meets the output trigger condition is designed. c (c=1,2,...,) is as follows:

[0045]

[0046] in, h represents a positive constant, represents the standard trigger threshold, v(k) represents the dynamic parameter, and its update standard is as follows, where x represents the prefabricated parameter:

[0047]

[0048] Indicates the output heading angle at the current moment; combined with the output trigger condition, the output heading angle at the current moment can be expressed as:

[0049]

[0050] Preferably, the pseudo partial derivative updating scheme includes:

[0051]

[0052] in, μ represents a positive constant, η∈(0,1];

[0053] The pseudo partial derivative reset mechanism is designed as follows:

[0054]

[0055] Among them, ε represents a preset positive value, express The initial value of Preferably, a data-driven dual-event triggered unmanned boat heading control device comprises:

[0056] The data acquisition module is used to obtain the actual heading angle and expected heading angle of the unmanned boat at each moment, and obtain the heading angle error of the unmanned boat at each moment;

[0057] Constructing a control model module, which is used to establish a nonlinear terminal sliding surface function according to the heading angle error of the unmanned boat, and to establish a second-order discrete sliding function according to the nonlinear terminal sliding surface function; according to the nonlinear terminal sliding surface function and the second-order discrete sliding function, designing an equivalent incremental control equation and a switching control equation and constructing a control model of the controller of the unmanned boat;

[0058] A control signal generation module is used to input the heading angle error of the unmanned boat at the current moment and the previous moment into the controller of the unmanned boat, and output the control signal at the current moment;

[0059] An input trigger condition judgment module is used to judge whether the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition based on the target control signal at the previous input trigger moment; if so, the current moment is set as the current input trigger moment, and the control signal at the current moment is sent to the actuator as the target control signal at the current input trigger moment; if not, the target control signal at the previous input trigger moment is sent to the actuator as the target control signal at the current input trigger moment;

[0060] The heading control module is used for the actuator to adjust and control the heading of the unmanned boat according to the target control signal received at the current moment; the output heading angle at the current moment is calculated according to the target control signal at the current moment and sent to the sensor;

[0061] The output trigger condition judgment module is used to judge whether the difference between the output heading angle at the current moment and the output heading angle at the previous output trigger moment meets the output trigger condition based on the target output signal at the previous output trigger moment; if so, the current moment is set as the current output trigger moment, and the output heading angle at the current moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment; if not, the output heading angle at the previous output trigger moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment;

[0062] The pseudo partial derivative updating module updates the pseudo partial derivatives in the equivalent incremental input control equation and the switching control equation according to the target control signal at the current input trigger moment, the target output signal at the current output trigger moment, and the pseudo partial derivative value at the previous input trigger moment, and transmits them to the controller of the unmanned boat; when the sum of the equivalent incremental control value and the switching control value at the current moment does not meet the input trigger condition, the pseudo partial derivative value at the previous input trigger moment is transmitted to the controller of the unmanned boat;

[0063] The loop control module is used to loop and iterate the above steps until the preset running time is reached, thereby ending the heading control of the unmanned boat.

[0064] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0065] The data-driven dual-event triggered unmanned boat heading control method described in the present invention uses a model-free adaptive sliding mode control method, and can realize the heading control of the unmanned boat without knowing the internal model information of the unmanned boat; at the same time, the method of the present invention takes into account the limited network communication resources and the influence of network delay, and designs a dual-channel event triggered communication mechanism, which reduces the response time. The data information must meet the set trigger conditions to trigger the next event, saving computing resources and avoiding repeated transmission of data information, solving the above-mentioned problems, so that the method of the present invention meets the actual application conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0067] Figure 1 is a flow chart of the USVs heading control system of the method of the present invention;

[0068] Figure 2 It is a schematic diagram of the dual-channel event triggering principle in a specific implementation mode of the present invention;

[0069] Figure 3 is a photo of the "Dolphin 1" small USVs in a specific embodiment of the present invention;

[0070] Figure 4 It is the time-invariant heading tracking performance in a specific embodiment of the present invention;

[0071] Figure 5 It is the time-varying heading tracking performance in a specific embodiment of the present invention;

[0072] Figure 6 is a forward channel event triggering interval diagram in a specific implementation manner of the present invention;

[0073] Figure 7 is a feedback channel event triggering interval diagram in a specific implementation mode of the present invention

[0074] Figure 8 It is a comparison chart of the triggering times of the method of the present invention and the conventional single-channel event triggering method;

[0075] Fig. 9 It is the overall algorithm flow chart of the method of the present invention. DETAILED DESCRIPTION

[0076] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0077] Example 1

[0078] Reference Figure 1 As shown, it is a flow chart of the USVs heading control system of the method of the present invention. The present invention is a data-driven dual-event triggered unmanned boat heading control method, comprising the following steps:

[0079] S1: Obtain the actual heading angle and expected heading angle of the unmanned boat at each moment, and obtain the heading angle error of the unmanned boat at each moment;

[0080] The heading angle error of the unmanned boat is expressed as follows:

[0081] E(k)=y d (k)-y(k)

[0082] Among them, y d y(k) represents the expected heading angle at the current moment k, and y(k) represents the actual heading angle at the current moment k.

[0083] S2: establishing a nonlinear terminal sliding surface function according to the heading angle error of the unmanned boat, and establishing a second-order discrete sliding mode function according to the nonlinear terminal sliding surface function; designing an equivalent incremental control equation and a switching control equation and constructing a control model of the controller of the unmanned boat according to the nonlinear terminal sliding surface function and the second-order discrete sliding mode function;

[0084] Compared with the traditional sliding surface function, the nonlinear terminal sliding surface function can achieve fast convergence and reduce the response time. The specific nonlinear terminal sliding surface function is established as follows:

[0085] s(k)=E(k)+α 1 E(k-1)+α 2 sig γ (E(k-1))

[0086] Among them, sig γ (E(k))=|E(k)| γ sgn(E(k)), sgn() is the sign function; α 1 , α 2 , γ are constant parameters, satisfying 0<α 1 <1、0<α 2 <1, 0<γ<1;

[0087] According to the nonlinear terminal sliding surface function s(k), a second-order discrete sliding function is established. In discrete time, the second-order discrete sliding mode function is used to describe the change relationship between the state parameters of the unmanned boat at two or more adjacent discrete time points. The specific second-order discrete sliding mode function is It is established as follows, where -1<β<0 represents the design parameter:

[0088]

[0089] According to the nonlinear terminal sliding surface function and the second-order discrete sliding function, the equivalent incremental input control equation and the switching control equation are designed to construct the input trigger controller of the unmanned boat. The equivalent incremental input control equation is designed as follows:

[0090]

[0091] Among them, Δu eq (k) represents the equivalent incremental control value, represents the pseudo partial derivative The estimated value of represents the pseudo partial derivative, σ represents a design constant; d(k) represents the interference value k receives at the current moment, which can be set according to different environmental conditions; Δd(k) = d(k) - d(k-1);

[0092] In order to further improve the robustness of the designed input-triggered controller, a switching control equation is designed to supplement the input-triggered controller. The specific design is as follows:

[0093]

[0094] Among them, λ s and q are constant parameters, satisfying the following conditionλ s >D, 0<q<1, D represents a positive real number.

[0095] Finally, the input trigger controller of the unmanned boat can be obtained, which is composed of the input control signal at the previous moment and the equivalent incremental input control equation Δu eq (k), switching control equation Δu sw (k) consists of three parts, as shown below:

[0096] u(k)=u(k-1)+Δu eq (k)+Δu sw (k)

[0097] S3: inputting the heading angle error of the unmanned boat at the current moment and the previous moment into the controller of the unmanned boat, and outputting the control signal at the current moment;

[0098] S4: Based on the target control signal at the last input trigger moment, determine whether the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition; if so, set the current moment as the current input trigger moment, and send the control signal at the current moment as the target control signal at the current input trigger moment to the actuator; if not, send the target control signal at the last input trigger moment as the target control signal at the current input trigger moment to the actuator;

[0099] When the unmanned boat is in a stable state, the amount of data in the input control signal changes very little. However, when using a periodic trigger mechanism, a large amount of duplicate data will continue to be transmitted even when the data changes very little. Therefore, the design of dual-channel trigger event control can effectively avoid the transmission of duplicate data.

[0100] Reference Figure 2 The figure shows the trigger principle framework of the dual-channel trigger event of the present invention. Therefore, the design input trigger condition specifically includes:

[0101] Define k r (r=1,2,...,) is the input trigger time that satisfies the input trigger condition; r represents the number of successful triggering of the input trigger condition, and the input trigger time k that satisfies the input trigger condition is designed. r (r=1,2,...,) as follows:

[0102]

[0103] Among them, z 1 (k) = Δu eq (k)+Δu sw (k); when z 1 (k) greater than When , it is successfully triggered; represents a positive constant, δ represents a constant parameter, satisfying 0<δ<1;

[0104] Combined with the input trigger condition, the input control signal at the current moment can be expressed as:

[0105]

[0106] By setting the input trigger condition, the method of the present invention can reduce 24% of energy waste compared with the existing method.

[0107] S5: The actuator adjusts and controls the heading of the unmanned boat according to the target control signal received at the current moment; calculates the output heading angle at the current moment according to the target control signal at the current moment and sends it to the sensor;

[0108] The actual heading angle at the next moment is expressed as follows:

[0109]

[0110] y(k+1)=F(k+1)+G 1 I(k+1)

[0111] Among them, F(k), I(k), u(k) represent the heading angle, angular velocity, and rudder angle of the current moment k, respectively. O and T represent the maneuvering coefficient. T s represents the sampling time, G 1 >0 indicates angular velocity feedback gain.

[0112] S6: Based on the target output signal at the last output triggering moment, determine whether the difference between the output heading angle at the current moment and the output heading angle at the last output triggering moment meets the output triggering condition; if so, set the current moment as the current output triggering moment, and send the output heading angle at the current moment as the target output signal at the current output triggering moment to the controller of the unmanned boat; if not, send the output heading angle at the last output triggering moment as the target output signal at the current output triggering moment to the controller of the unmanned boat;

[0113] Define k c (c=1,2,...,) as the output trigger condition, indicating the output trigger moment; c represents the number of times the output trigger condition is successfully triggered, and the output trigger condition k c (c=1,2,...,) The design is as follows:

[0114]

[0115] in, h represents a positive constant, represents the standard trigger threshold, x represents the prefabricated parameter, v(k) represents the dynamic parameter, and its update standard is as follows:

[0116]

[0117] Represents the estimated value of the actual heading angle y(k) at the current time k; after combining the output trigger condition, It can be expressed as:

[0118]

[0119] By setting the output triggering conditions, the method of the present invention can reduce 12.5% ​​of energy waste compared with the existing method.

[0120] At the same time, when the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition, the pseudo-partial derivative in the equivalent incremental input control equation and the switching control equation are updated according to the target control signal at the current input trigger moment, the target output signal at the current output trigger moment, and the pseudo-partial derivative value at the previous input trigger moment, and transmitted to the controller of the unmanned boat; when the sum of the equivalent incremental control value and the switching control value at the current moment does not meet the input trigger condition, the pseudo-partial derivative value at the previous input trigger moment is transmitted to the controller of the unmanned boat.

[0121] Among them, the pseudo partial derivative update scheme is expressed as follows:

[0122]

[0123] In order to make the pseudo partial derivative algorithm equation have a stronger ability to track time-varying parameters, the pseudo partial derivative reset mechanism is designed as follows:

[0124]

[0125] Where ε represents a preset positive value, express The initial value of

[0126] S7: The above steps are repeated repeatedly until the preset running time is reached, and the heading control of the unmanned boat is terminated. Fig. 9 The figure shows the overall algorithm flow chart of the method of the present invention.

[0127] Example 2

[0128] Based on Example 1, this example builds a small USV "Dolphin 1" to verify the correctness and effectiveness of the proposed method. Figure 3 As shown, the "Dolphin 1" small USV is 2 meters long and 1 meter wide, with a displacement of 55.0 kg. The maximum speed of the USV is 1.5 meters per second. The power drive mode is twin propellers or single propellers.

[0129] The USVs heading control subsystem model is:

[0130]

[0131] Where O and T represent the maneuvering coefficients, T s represents the sampling time. F(k), I(k), u(k) represent the heading angle, angular velocity and rudder angle respectively.

[0132] Redefine the USVs heading control subsystem, and the actual heading angle at the next moment is as follows:

[0133] y(k+1)=F(k+1)+G1 I(k+1)

[0134] Among them G 1 >0 is the angular velocity feedback gain.

[0135] The target heading is set to y d (k+1)=3.5sin(kπ / 50), interference d(k)=0.1(1+0.1cos(0.3k)+0.1sin(0.5k)), the main parameters are designed as μ=1, η=0.1, ε=1e-5, T=0.332, T s =0.1, G 1 =22,α 1 =0.2,λ s =0.0001, x=0.5, h=20, q=0.8, δ=0.001,

[0136] Reference Figure 4 It can be seen that the method proposed by the present invention converges when k=28, and then stably tracks the target trajectory. In contrast, the existing method does not converge until k=140, and is greatly affected by interference, causing fluctuations around the target trajectory. The method has fast convergence speed, strong anti-interference ability, and small tracking error.

[0137] Example 3

[0138] Based on Example 1, this example builds a small USV "Dolphin 1" to verify the correctness and effectiveness of the proposed method. Figure 3 The "Dolphin 1" small USV shown is 2 meters long and 1 meter wide. The displacement of the USV is 55.0 kg. The maximum speed of the USV is 1.5 meters per second. The power drive mode is twin propellers or single propellers.

[0139] The USVs heading control subsystem model is:

[0140]

[0141] Where O and T represent the maneuvering coefficients, T s represents the sampling time. F(k), I(k), u(k) represent the heading angle, angular velocity and rudder angle respectively.

[0142] Redefine the USVs heading control subsystem, and the actual heading angle at the next moment is as follows:

[0143] y(k+1)=F(k+1)+G 1 I(k+1)

[0144] Among them G 1>0 is the angular velocity feedback gain. The main parameters are designed as follows: μ = 1, η = 0.1, ε = 1e-5, T = 0.332, T s =0.1, G 1 =22,α 1 =0.2,λ s =0.0001, x=0.5, h=20, q=0.8, δ=0.001,

[0145] The target heading is set to y d (k+1)=3.5sin(kπ / 50), interference d(k)=0.1(1+0.1cos(0.3k)+0.1sin(0.5k)), such as Figure 5 We can see that the method proposed in this paper has stronger robustness and can achieve more accurate tracking. Figure 6 , 7 For the forward channel and feedback channel event trigger interval diagram of the present invention, refer to Figure 8 This is a comparison chart of the triggering times of the present method and the previous single-channel event triggering method. It can be seen that the method of the present invention can better meet the requirements of the heading control accuracy of the unmanned underwater vehicle and can better handle unknown interference.

[0146] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0147] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0148] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0149] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0150] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A data-driven dual-event triggered unmanned boat heading control method, characterized in that: The following steps are involved: Obtain the actual heading angle and expected heading angle of the unmanned boat at each moment, and obtain the heading angle error of the unmanned boat at each moment; A nonlinear terminal sliding surface function is established according to the heading angle error of the unmanned boat, and a second-order discrete sliding function is established according to the nonlinear terminal sliding surface function; based on the nonlinear terminal sliding surface function and the second-order discrete sliding function, an equivalent incremental control equation and a switching control equation are designed and a control model of the controller of the unmanned boat is constructed; Inputting the heading angle error of the unmanned boat at the current moment and the previous moment into the controller of the unmanned boat, and outputting the control signal at the current moment; Based on the target control signal at the last input triggering moment, determining whether the sum of the equivalent incremental control value and the switching control value at the current moment meets the input triggering condition; If satisfied, the current time is set as the current input trigger time, and the control signal at the current time is sent to the actuator as the target control signal at the current input trigger time; If not, the target control signal at the last input triggering moment is sent to the actuator as the target control signal at the current input triggering moment; The actuator adjusts and controls the heading of the unmanned boat according to the target control signal received at the current moment; calculates the output heading angle at the current moment according to the target control signal at the current moment and sends it to the sensor; Based on the target output signal at the last output triggering moment, determine whether the difference between the output heading angle at the current moment and the output heading angle at the last output triggering moment satisfies the output triggering condition; If satisfied, the current moment is set as the current output trigger moment, and the output heading angle at the current moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment; if not satisfied, the output heading angle at the previous output trigger moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment; At the same time, when the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition, the pseudo partial derivative in the equivalent incremental input control equation and the switching control equation is updated according to the target control signal at the current input trigger moment, the target output signal at the current output trigger moment, and the pseudo partial derivative value at the previous input trigger moment, and transmitted to the controller of the unmanned boat; when the sum of the equivalent incremental control value and the switching control value at the current moment does not meet the input trigger condition, the pseudo partial derivative value at the previous input trigger moment is transmitted to the controller of the unmanned boat; The above steps are iterated repeatedly until the preset running time is reached, and the heading control of the unmanned boat is ended.

2. According to claim 1, a data-driven dual-event triggered unmanned boat heading control method is characterized in that: The unmanned boat heading angle error is expressed as follows: E(k)=y d (k)-y(k) Among them, y d y(k) represents the expected heading angle at the current moment k, and y(k) represents the actual heading angle at the current moment k.

3. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The nonlinear terminal sliding surface function is expressed as follows: s(k)=E(k)+α1E(k-1)+α2sig γ (E(k-1)) E(k) represents the heading angle error of the unmanned boat at the current moment k, sig γ (E(k))=|E(k)| γ sgn(E(k)), sgn() is a sign function; α1, α2, γ all represent constant parameters, satisfying 0<α1<1, 0<α2<1, 0<γ<1; The second-order discrete sliding mode function is expressed as follows, where -1<β<0 represents the design parameter:

4. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The equivalent incremental control equation is expressed as follows: Where E(k) represents the heading angle error of the unmanned boat at the current time k, Δu eq (k) represents the equivalent incremental control value, represents the pseudo partial derivative The estimated value of represents the pseudo partial derivative, σ represents a design constant; d(k) represents the interference value k receives at the current moment, Δd(k) = d(k) - d(k-1); The switching control equation is expressed as follows: Among them, Δu sw (k) represents the switching control value, λ s and q are constant parameters, satisfying the following conditionλ s >D, 0<q<1, D represents a positive real number.

5. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The control model of the controller of the unmanned boat is expressed as follows: u(k)=u(k-1)+Δu eq (k)+Δu sw (k) Among them, u(k) represents the control signal of the unmanned boat at the current moment, Δu eq (k) represents the equivalent incremental control value at the current moment, Δu sw (k) represents the switching control value at the current moment.

6. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The input trigger conditions include: Define k r (r=1,2,...,) is the input trigger time that satisfies the input trigger condition; r represents the number of successful triggering of the input trigger condition, and the input trigger time k that satisfies the input trigger condition is designed. r (r=1,2,...,) as follows: Where z1(k) = Δu eq (k)+Δu sw (k); when z1(k) is greater than When , it is successfully triggered; represents a positive constant, δ represents a constant parameter, satisfying 0<δ<1; Combined with the input trigger condition, the control signal at the current moment can be expressed as:

7. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The output heading angle at the current moment is expressed as follows: y(k+1)=F(k+1)+G1I(k+1) Among them, F(k), I(k), u(k) represent the heading angle, angular velocity, and rudder angle of the current moment k, respectively. O and T represent the maneuvering coefficient. T s represents the sampling time, and G1>0 represents the angular velocity feedback gain.

8. The data-driven dual-event triggered unmanned boat heading control method according to claim 1 is characterized in that: The output trigger conditions include: Define k c (c=1,2,...,) is the output trigger time that meets the output trigger condition; c represents the number of successful triggering of the output trigger condition, and the output trigger time k that meets the output trigger condition is designed. c (c=1,2,...,) is as follows: in, h represents a positive constant, represents the standard trigger threshold, v(k) represents the dynamic parameter, and its update standard is as follows, where x represents the prefabricated parameter: Indicates the output heading angle at the current moment; combined with the output trigger condition, the output heading angle at the current moment can be expressed as:

9. The data-driven dual-event triggered unmanned boat heading control method according to claim 9 is characterized in that: The pseudo partial derivative updating scheme includes: in, μ represents a positive constant, η∈(0,1]; The pseudo partial derivative reset mechanism is designed as follows: Among them, ε represents a preset positive value, express The initial value of 10. A data-driven dual-event triggered unmanned boat heading control device, characterized in that: include: The data acquisition module is used to obtain the actual heading angle and expected heading angle of the unmanned boat at each moment, and obtain the heading angle error of the unmanned boat at each moment; Constructing a control model module, which is used to establish a nonlinear terminal sliding surface function according to the heading angle error of the unmanned boat, and to establish a second-order discrete sliding function according to the nonlinear terminal sliding surface function; according to the nonlinear terminal sliding surface function and the second-order discrete sliding function, designing an equivalent incremental control equation and a switching control equation and constructing a control model of the controller of the unmanned boat; A control signal generation module is used to input the heading angle error of the unmanned boat at the current moment and the previous moment into the controller of the unmanned boat, and output the control signal at the current moment; An input trigger condition judgment module is used to judge whether the sum of the equivalent incremental control value and the switching control value at the current moment meets the input trigger condition based on the target control signal at the previous input trigger moment; If satisfied, the current time is set as the current input trigger time, and the control signal at the current time is sent to the actuator as the target control signal at the current input trigger time; If not, the target control signal at the last input triggering moment is sent to the actuator as the target control signal at the current input triggering moment; The heading control module is used for the actuator to adjust and control the heading of the unmanned boat according to the target control signal received at the current moment; the output heading angle at the current moment is calculated according to the target control signal at the current moment and sent to the sensor; An output trigger condition judgment module is used to judge whether the difference between the output heading angle at the current moment and the output heading angle at the last output trigger moment meets the output trigger condition based on the target output signal at the last output trigger moment; If satisfied, the current moment is set as the current output trigger moment, and the output heading angle at the current moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment; if not satisfied, the output heading angle at the previous output trigger moment is sent to the controller of the unmanned boat as the target output signal at the current output trigger moment; The pseudo partial derivative updating module updates the pseudo partial derivatives in the equivalent incremental input control equation and the switching control equation according to the target control signal at the current input trigger moment, the target output signal at the current output trigger moment, and the pseudo partial derivative value at the previous input trigger moment, and transmits them to the controller of the unmanned boat; when the sum of the equivalent incremental control value and the switching control value at the current moment does not meet the input trigger condition, the pseudo partial derivative value at the previous input trigger moment is transmitted to the controller of the unmanned boat; The loop control module is used to loop and iterate the above steps until the preset running time is reached, thereby ending the heading control of the unmanned boat.

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