Inland ship active-disturbance-rejection control method based on guidance law and parameter self-adaption

Abstract

The invention relates to the technical field of inland ship control, in particular to an inland ship active-disturbance-rejection control method based on a guidance law and parameter self-adaption, which comprises the following steps: S1, determining a course control strategy of an inland ship, and analyzing lateral displacement data of the inland ship to obtain a drift angle of the inland ship, performing drift angle compensation on the course control strategy to obtain a guidance law; s2, designing a parameter adaptive strategy of the controller of the inland ship; and S3, the control system of the inland ship adjusts the navigation state of the inland ship according to the guidance law and the parameter adaptive strategy. The invention provides an inland ship active-disturbance-rejection control method based on a guidance law and parameter self-adaption, solves the technical problems that in the prior art, the navigation control precision of an inland ship is low, and fixed controller parameters cannot adapt to course and track control of different tasks at various navigational speeds, and improves the navigation control precision of the inland ship.

Description

Technical Field

[0001] The present invention relates to the technical field of inland ship control, and particularly to an active disturbance rejection control method for inland ships based on a guidance law and parameter adaptation. Background Technique

[0002] Inland waterway shipping plays a key role in promoting regional trade and economic development due to its advantages such as large carrying capacity, low cost, and small energy consumption. Compared with sea navigation, inland navigation faces challenges such as narrow waterways and limited water depth, which require ships to precisely control their course and speed during navigation. To adapt to the particularity of inland waterways, inland ships are usually designed with a shallower draft and a wider hull, which makes them less capable of withstanding wind compared to seagoing ships. In addition, the hydrological conditions in different sections of inland waterways vary significantly, and the influence of water level fluctuations and downstream tides makes the water flow condition complex and changeable, and the water flow disturbance effect is more intense. In view of this, it is particularly crucial to deeply study the technology for achieving high-precision control of inland ships under the interference of different speeds and wind and current environments.

[0003] In the prior art, the commonly used active disturbance rejection controller is a linear active disturbance rejection control, and the controller parameters and observer parameters are determined through continuous debugging and will not change with the change of the ship's motion state. When the ship's speed changes and causes the maneuverability to change, the traditional linear active disturbance rejection control will be difficult to maintain an ideal control effect. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the related art. For this purpose, the present invention provides an active disturbance rejection control method for inland ships based on a guidance law and parameter adaptation, which solves the technical problems of low accuracy of inland ship navigation control and inability of fixed controller parameters to adapt to course and track control under various speeds in different tasks in the prior art, and improves the navigation control accuracy of inland ships.

[0005] The present invention provides an active disturbance rejection control method for inland ships based on a guidance law and parameter adaptation, including: S1, determining the course control strategy of the inland ship, analyzing the lateral displacement data of the inland ship to obtain the drift angle of the inland ship, and compensating the course control strategy for the drift angle to obtain a guidance law, specifically , where represents the course command, represents the angle between the track segment and the due north direction, represents the track deviation, represents the forward-looking vector, represents the lateral velocity signal of the inland ship, represents the speed of the inland ship; S2, designing a parameter adaptation strategy for the controller of the inland ship, and the parameter adaptation strategy is , where represents the first parameter of the controller, represents the second parameter of the controller, represents the turning index, represents the responsiveness index; S3. The control system of the inland river ship adjusts the navigation state of the inland river ship according to the guidance law and the parameter adaptive strategy.

[0006] A further improvement of the active disturbance rejection control method for inland river ships based on guidance law and parameter adaptation of the present invention is that the S1 step includes: The guidance law adopts a straight-line line-of-sight navigation algorithm, and the starting waypoint of the inland river ship is set as , the first target waypoint of the inland river ship is set as , the second target waypoint of the inland river ship is set as , then the first target track of the inland river ship is , the second target track of the inland river ship is , The current position of the inland river ship when traveling on the first target track is set as , At this time is the angle between the first target track segment and the due north direction, and the calculation method is ; The track deviation of the inland river ship at the current position is calculated as being . The spatial meaning of the track deviation is the vertical distance from the current position of the inland river ship to the first target track segment.

[0007] A further improvement of the active disturbance rejection control method for inland river ships based on guidance law and parameter adaptation of the present invention is that the S1 step further includes: Design the initial heading command of the inland river ship according to the track deviation as , where represents the initial heading command, represents the forward-looking vector.

[0008] A further improvement of the active disturbance rejection control method for inland river ships based on guidance law and parameter adaptation of the present invention is that the S1 step further includes: The inland river ship has a tracking differentiator module to obtain the lateral displacement data of the inland river ship during actual navigation, input the lateral displacement data into the tracking differentiator module, and then the tracking differentiator module outputs a lateral velocity signal ; Obtain the ship speed of the inland river ship, and based on the lateral velocity signal The drift angle of the inland river ship can be calculated as ; Adding the drift angle compensation to the initial heading command, the heading command of the guidance law can be obtained as .

[0009] A further improvement of the active disturbance rejection control method for inland river ships based on the guidance law and parameter adaptation of the present invention lies in that the step S2 includes: The controller of the inland river ship is a second-order system, and the time-domain differential equation of the second-order system is , where represents the angular velocity of the bow, that is, the turning rate of the bow, represents the acceleration of the bow, represents the turning index, represents the responsiveness index, represents the rudder angle; Assuming that the initial condition is zero, the transfer function obtained after Laplace transform is: where is the natural frequency of the system, is the damping ratio of the system, represents the Laplace variable; According to the comparison of the time-domain differential equation and the transfer function, it is obtained that , Setting the system damping ratio , the gain of the controller can be obtained as .

[0010] A further improvement of the active disturbance rejection control method for inland river ships based on the guidance law and parameter adaptation of the present invention lies in that the rotational speed of the propeller of the inland river ship is 60 rpm to 120 rpm.

[0011] A further improvement of the active disturbance rejection control method for inland river ships based on the guidance law and parameter adaptation of the present invention lies in that after the step S3, it further includes performing a simulation test on the course and track control of the inland river ship based on the MATLAB simulation platform.

[0012] A further improvement of the active disturbance rejection control method for inland river ships based on the guidance law and parameter adaptation of the present invention lies in that it further includes: constructing a simulation model of the inland river ship, an environmental disturbance model, a course control module and a track control module on the MATLAB simulation platform to perform a course control of the inland river ship at different speeds and a simulation test on the track control under the influence of wind and current disturbances.

[0013] In one or more of the above technical solutions in the embodiments of the present invention, the guidance law can be obtained by adding drift angle compensation to the initial heading command. This guidance law fully considers the dynamic characteristics of inland river ships in complex environments. Especially when facing external disturbances such as water flow and wind, it can significantly improve the accuracy and stability of heading control. The compensation of the drift angle not only optimizes the navigation trajectory of the ship but also effectively reduces the heading deviation caused by environmental factors. In practical applications, this guidance law can ensure that inland river ships maintain the expected heading under various working conditions, thereby greatly improving the safety and efficiency of navigation. Furthermore, the parameter control method is improved based on the second-order system of inland river ships, and combined with parameter adaptive control, it can dynamically adjust control parameters according to the actual operating state of the ship, further enhancing the robustness and adaptability of the system.

[0014] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 It is a block diagram of the active disturbance rejection control method for inland river ships based on the guidance law and parameter adaptation provided by the embodiments of the present invention.

[0017] Figure 2 It is a schematic diagram of the straight-line line-of-sight navigation algorithm.

[0018] Figure 3 It is a schematic diagram of the speed and yaw rate curves of an inland river ship at different propeller speeds.

[0019] Figure 4 It is a schematic diagram of the heading control result at a propeller speed of 120 rpm for a 30° heading control task in the simulation test.

[0020] Figure 5 It is a schematic diagram of the heading control result at a propeller speed of 90 rpm for a 30° heading control task in the simulation test.

[0021] Figure 6 It is a schematic diagram of the heading control result at a propeller speed of 60 rpm for a 30° heading control task in the simulation test.

[0022] Figure 7It is a schematic diagram of the heading control result at a propeller speed of 120 rpm under the 60° heading control task in the simulation test.

[0023] Figure 8 It is a schematic diagram of the heading control result at a propeller speed of 90 rpm under the 60° heading control task in the simulation test.

[0024] Figure 9 It is a schematic diagram of the heading control result at a propeller speed of 60 rpm under the 60° heading control task in the simulation test.

[0025] Figure 10 It is a schematic diagram of the track control result of the embodiment of the present invention. Detailed implementation manners

[0026] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0027] The following combines Figure 1 and Figure 2 to describe an active disturbance rejection control method for inland river ships based on guidance law and parameter adaptation of the present invention, including: S1. Determine the heading control strategy of the inland river ship, analyze the lateral displacement data of the inland river ship to obtain the drift angle of the inland river ship, and perform drift angle compensation on the heading control strategy to obtain a guidance law, specifically , where represents the heading command, represents the angle between the track segment and the due north direction, represents the track deviation, represents the forward-looking vector, represents the lateral velocity signal of the inland river ship, represents the speed of the inland river ship; S2. Design the parameter adaptation strategy of the controller of the inland river ship, and the parameter adaptation strategy is , where represents the first parameter of the controller, represents the second parameter of the controller, represents the gyration index, represents the response rudder index; S3. The control system of the inland river ship adjusts the navigation state of the inland river ship according to the guidance law and the parameter adaptation strategy.

[0028] In a preferred embodiment of the active disturbance rejection control method for inland river ships based on guidance law and parameter adaptation, step S1 includes: In order to make the track deviation of the inland river ship asymptotically converge to zero, the guidance law adopts the straight-line line-of-sight navigation algorithm, and the starting waypoint of the inland river ship is set as Set the first target waypoint of the inland river ship as Set the second target waypoint of the inland river ship as Then the first target track of the inland river ship is The second target track of the inland river ship is , Set the current position of the inland river ship when traveling on the first target track as , At this time Is the angle between the first target track segment and the due north direction, and the calculation method is ; Calculate the track deviation of the inland river ship at the current position Is The spatial meaning of the track deviation is the perpendicular distance from the current position of the inland river ship to the first target track segment.

[0029] According to the angle between the first target track segment and the due north direction and the track deviation , use the straight-line line-of-sight navigation algorithm to generate the desired heading angle of the inland river ship, and this desired heading angle is used to guide the inland river ship to travel along the first target track.

[0030] Specifically, step S1 further includes: Design the initial heading command of the inland river ship according to the track deviation as , Among them, Represents the initial heading command, Represents the forward-looking vector, usually selected as 2 to 5 times the length of the inland river ship.

[0031] Furthermore, in the inland river environment, the wind and current disturbance information received by the inland river ship is relatively strong. Only setting the track control strategy according to the initial heading command will result in a static error in track control; Specifically, step S1 further includes: The heading control of the inland river ship has a tracking differentiator module, which obtains the lateral displacement data of the inland river ship during actual navigation, inputs the lateral displacement data into the tracking differentiator module, and then the tracking differentiator module outputs a lateral velocity signal , the lateral velocity signal reflects the tendency and its rate of change of an inland river ship deviating from the predetermined track during navigation. Through this signal, the system can capture the dynamic behavior of the ship more accurately, providing a key basis for subsequent adjustment of control strategies; Obtain the ship speed of an inland river ship , based on the lateral velocity signal The drift angle of the inland river ship can be calculated as ; Adding the drift angle compensation to the initial heading command, the heading command of the guidance law can be obtained as .

[0032] The ship speed can be obtained in real time through the ship speed sensor carried by the ship, ensuring the accuracy and real-time nature of the data. The calculation of the drift angle is derived based on the ship dynamics principle, combining the lateral velocity signal and the ship speed, which reflects the degree of deflection of the ship under the action of lateral force during navigation. Adding the calculated drift angle compensation to the initial heading command can effectively offset the influence of external factors such as wind and current on the ship track, thereby improving the accuracy and stability of track control. The heading command of the guidance law obtained in this way can better fit the actual navigation state of the inland river ship, providing a more accurate heading reference for subsequent active disturbance rejection control strategies.

[0033] To further improve the control accuracy and robustness, a parameter adaptive mechanism is introduced. According to the actual navigation state of the inland river ship and the changes in the external environment, the control parameters are dynamically adjusted to ensure that the inland river ship can stably and accurately track the desired heading angle, thereby achieving the asymptotic convergence of the track.

[0034] In a specific implementation case, the design process of the parameter adaptive active disturbance rejection controller is as follows: The dynamic model of the inland river ship's bow direction is , which is a simplified first-order model describing the bow movement of the inland river ship. Among them, represents the bow angular velocity, that is, the turning rate of the bow, represents the bow acceleration, represents the rudder angle, represents the total system disturbance, represents the turning index, represents the response rudder index; The turning index and the response rudder index can be obtained through ship maneuverability tests .

[0035] Specifically, expand the total system disturbance into three state variables , and select the three state variables as: , among which, is the actual ship heading, is the heading derivative, is the total system disturbance, and thus the extended state space equation is obtained as , where , in which ; through state extension, the total system disturbance is regarded as an observable and compensable quantity, enhancing the system robustness.

[0036] Furthermore, the linear extended state observer (LESO) corresponding to the extended state space equation can be designed as: , where is the observed value of the state matrix , is the actual ship heading, is 's estimated value, is the output matrix, , in which represents the observed value of the state variable , represents the observed value of the state variable , represents the observed value of the state variable , is the gain matrix of the error feedback control of the linear extended state observer. By adjusting the gain matrix, can quickly track the true states of the three state variables , realizing the real-time estimation of .

[0037] Preferably, according to the mathematical relationship, it can be known that the heading derivative i.e., represents the heading angular velocity , that is, , then the derivative of the heading angular velocity represents the derivative of the heading derivative , thus having , and further substituting it into the dynamic model of the inland river ship's heading, we can obtain ; Generally, in ship maneuvering control, the relationship between the control input and the rudder angle is introduced. Assuming and have a linear relationship , this linear relationship is assumed according to , aiming to convert the rudder angle into the form of the control input; Substitute into and simplify to obtain , and since , it can be further transformed into ; ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Assume that there is an expected heading acceleration , for After rearrangement, we get .

[0038] Furthermore, by combining and applying the PD control law, we obtain , where represents the PD control law, represents the first parameter of the controller, represents the second parameter of the controller; By transforming , we have . Currently, the gain parameters of the controller are selected in the traditional active disturbance rejection controller .

[0039] In practical applications, the natural frequency of the system needs to be adjusted according to the speed and steady-state requirements of the system output tracking target. A small parameter will result in a slow convergence speed, and a large parameter will cause system oscillation. To address this issue, the adjustment relationship of the gain parameters is further improved.

[0040] Furthermore, step S2 includes: The controller of the inland river ship is a second-order system, and the time-domain differential equation of the second-order system is , where represents the heading angular velocity, i.e., the turning rate, represents the heading acceleration, represents the turning index, represents the response rudder index, represents the rudder angle; According to the properties of the Laplace transform: If The Laplace transform of is , then its derivative The Laplace transform of is (in the case of zero initial conditions); Taking the Laplace transform of both sides of the time-domain differential equation simultaneously: The left side of the equation After transformation, it becomes , After transformation, it becomes ; The right side of the equation , Let The Laplace transform of is , then after transformation, it becomes ; At this time, we get ; Further extracting the common factor , we get ; According to the definition of the transfer function (the ratio of the Laplace transform of the system output to the Laplace transform of the input), then ; The standard transfer function form of a second-order system is: where is the natural frequency of the system, is the damping ratio of the system, represents the Laplace variable; By comparing and parameters, we get , Set the system damping ratio , and the gain of the controller can be obtained as .

[0041] Preferably, the propeller speed of the inland river ship is 60 rpm to 120 rpm.

[0042] Specifically, after step S3, it also includes based on the MATLAB simulation platform to conduct the track control simulation test of the inland river ship. On the MATLAB simulation platform, a simulation model of the inland river ship, an environmental disturbance model, a heading control module, and a track control module are constructed to conduct the heading control of the inland river ship at different speeds and the track control simulation test under the influence of wind and current disturbances.

[0043] In the simulation test of the maneuverability of the inland river ship at different propeller speeds, the target of the active disturbance rejection control method designed by the present invention is to solve the adaptive control problem of the change of the ship's maneuvering characteristics at different speeds. Therefore, first, the change of the maneuverability of the inland river ship at different speeds is tested. The propeller speeds of the ship are set to 60 rpm, 90 rpm, and 120 rpm respectively, and the ship speeds and the change rates of the heading rate at the three propeller speeds are recorded and the change rate of maneuverability is statistically analyzed. The test results are shown in Table 1: Table 1 By comparing the data at different propeller speeds, it can be clearly observed that as the propeller speed increases, the ship speed of the ship increases correspondingly, and the heading rate also rises. The change ratio of the heading rate shows the amplitude of the change of the ship's maneuverability at different propeller speeds. From the data in the table, it can be seen that when the propeller speed is increased from 60 rpm to 90 rpm, the heading rate increases by 50%, and when the propeller speed is increased from 90 rpm to 120 rpm, the heading rate increases by 36%. This shows that the maneuvering characteristics of the ship do change at different speeds, and this change is closely related to the propeller speed.

[0044] Course control simulation test: To test the control effect of the proposed self-disturbance rejection control method for inland river ship course based on parameter adaptation when the ship's navigation state changes, the control method of the present invention is tested under the same control conditions and environmental conditions as the traditional linear self-disturbance rejection control algorithm. Hereinafter, the control method of the present invention is denoted as IADRC, and the traditional control method is denoted as ADRC. By testing the course control effect at different ship speeds, the control performances of the two control algorithms are compared.

[0045] Set the initial ship speed of the inland river ship to 0 and the initial course to 0°. The commanded course is 30°. Test the course control effects under the conditions of propeller speeds of 120 rpm, 90 rpm, and 60 rpm respectively. To test the robustness to environmental disturbances, when the program runs to 500 seconds, random wind and current environmental disturbance information is added. The simulation results are as Figures 3 to 9 shown. It can be seen from Figure 3 that by adopting the guidance law and parameter adaptation control method of the present invention, when the inland river ship faces various external disturbances, the accuracy and stability of course control have been significantly improved, and the safety and efficiency of navigation have also been significantly enhanced, proving its strong robustness and adaptability.

[0046] As Figure 4 shown, under the IADRC control strategy, the course quickly converges to the target value, with a short response time, and the steady-state error is controlled within 1°. When a disturbance is introduced (at 500 seconds), the fluctuation of the course is small, and the system can return to the stable state in about 20 seconds. In contrast, although the ADRC control strategy has a rapid initial response, there is an overshoot of 5°. Under the action of the disturbance, the fluctuation amplitude of the course can reach 8°, and the recovery time exceeds 50 seconds. The conclusion points out that under high-speed conditions, IADRC effectively suppresses the overshoot phenomenon through the parameter adaptation mechanism, and its anti-disturbance ability is significantly better than that of the traditional ADRC, thus verifying the excellent stability of IADRC during high-speed ship navigation.

[0047] In the course control simulation results of 30° and 60°, as Figures 4 to 9 shown, at 120 rpm, both ADRC and IADRC show good control effects, and they basically coincide with the commanded course before the disturbance is added and there is no overshoot. However, as the ship speed decreases, ADRC has an overshoot, and the overshoot amount increases continuously as the ship speed decreases. For the IADRC algorithm, since the controller can adaptively change with the ship speed, from the course control response curve, when the ship speed decreases, the course control response does not change significantly, indicating that IADRC does not need to readjust the parameters when the ship's navigation state changes, showing strong self-adaptability.

[0048] As Figure 4As shown, this figure presents the comparison between IADRC and ADRC for 30° heading control at a propeller speed of 120 rpm. From Figure 4 it can be seen from (a) that IADRC responds quickly to the command in the initial stage, the heading curve is smooth and there is no overshoot, while ADRC has an overshoot of about 5°; Figure 4 as shown in (b), the heading error of IADRC converges to ±2° within 100 seconds, while the error of ADRC fluctuates greatly after the disturbance is added; in terms of rudder angle response ( Figure 4 (c)), the change of the rudder angle of IADRC is gentler, and the maximum rudder angle is only 15°, while ADRC has a sharp fluctuation of 25° after the disturbance, which indicates that IADRC has stronger anti-disturbance ability and stability at high speeds.

[0049] As Figure 5 shown, when the speed drops to 90 rpm, the inertia of the ship increases, Figure 5 in (a), IADRC can still maintain the accuracy of heading tracking, while ADRC has a deviation of about 8° after 500 seconds of disturbance; Figure 5 as shown in (b), the steady-state error of IADRC stabilizes at ±1°, while the error of ADRC continues to oscillate after the disturbance; in terms of the rudder angle ( Figure 5 (c)), the control command of IADRC is softer, and the average rudder angle is only 10°, while the fluctuation amplitude of the rudder angle of ADRC is as high as 20°. The results show that IADRC can still compensate for the dynamic changes of the system through parameter self-adaptation at low speeds.

[0050] As Figure 6 shown, at the lowest speed of 60 rpm, the ship's power drops significantly, Figure 6 as shown in (a), IADRC completes the heading adjustment within 150 seconds, while ADRC takes 250 seconds and there is a continuous deviation; Figure 6 in (b), the maximum error of IADRC is only 3°, while the error peak of ADRC reaches 12° after the disturbance; the rudder angle response ( Figure 6 (c)) shows that IADRC can still maintain effective control at low speeds through adaptive gain adjustment, and the change of the rudder angle is stable; ADRC has a sharp oscillation of the control command due to fixed parameters, and the highest rudder angle reaches 30°.

[0051] As Figure 7 shown, for large-angle turning (60°), IADRC shows a faster response speed at high speeds; Figure 7 as shown in (a), IADRC completes the turning within 200 seconds, while ADRC has an obvious delay; the heading error ( Figure 7(b), the maximum dynamic error of IADRC is only 5°, and the steady-state error is less than 1°. During the steering process of ADRC, the peak error reaches 15°, and it recovers slowly after disturbance; Rudder angle control ( Figure 7 (c) shows that by optimizing the control rate, IADRC keeps the rudder angle changing smoothly during large-angle steering, while ADRC shows high-frequency oscillation.

[0052] As Figure 8 shown, when the rotational speed decreases to 90 rpm, IADRC can still effectively compensate for the system nonlinearity; Figure 8 (a) shows that the heading curve of IADRC is close to the ideal step response, while there is a lag of about 10° in the initial stage of steering for ADRC; Figure 8 (b), the steady-state error of IADRC is always less than 2°, while the error of ADRC fluctuates continuously after disturbance; Rudder angle response ( Figure 8 (c) shows that through parameter adaptive adjustment, IADRC maintains the effectiveness of the rudder angle at low rotational speeds, while the rudder angle command of ADRC shows unnecessary high-frequency jitter.

[0053] As Figure 9 shown, at an extremely low rotational speed of 60 rpm, the ship's maneuverability is severely limited; Figure 9 (a) shows that IADRC can still achieve a 60° turn, while the heading deviation of ADRC reaches 20° after disturbance; Figure 9 (b), the error of IADRC converges to ±3° within 300 seconds, while the error of ADRC continues to diverge; Rudder angle control ( Figure 9 (c) shows that by dynamically adjusting the control gain, IADRC can still output reasonable rudder angle commands at low rotational speeds, while due to fixed parameters, ADRC fails to control, and the rudder angle shows abnormal fluctuations.

[0054] To quantitatively analyze the control capabilities of the traditional active disturbance rejection control (ADRC) algorithm and the IADRC control algorithm proposed in the present invention under changes in ship conditions and environmental disturbances such as wind and current, the root mean square of the heading control error under different navigation states is recorded in Table 2; Table 2 It can be seen from Table 2 that during the entire heading control process, compared with the traditional ADRC algorithm, under the same simulation conditions, the control accuracy of the IADRC control algorithm proposed in the present invention can be improved by more than 2 times, further verifying the adaptability of the IADRC control algorithm designed in the present invention to changes in ship conditions and its strong robustness to environmental disturbances.

[0055] The IADRC significantly improves the control performance of inland river ships under different speeds and headings through a parameter adaptive mechanism. Compared with traditional ADRC, the IADRC performs better in terms of response speed, steady-state accuracy, disturbance rejection ability, and rudder angle smoothness, especially showing obvious advantages at low rotational speeds and large-angle turns. The trajectory control experiment further verifies the robustness and adaptability of the improved method in complex navigation scenarios, providing an effective solution for the intelligent control of inland river ships.

[0056] Trajectory control simulation test: As Figure 10 shown, adopting an indirect trajectory control strategy, converting trajectory control into heading control, the guidance law ILOS of the present invention and the traditional guidance law LOS without drift angle compensation convert the commanded trajectory into a commanded heading, and use the parameter adaptive strategy of the present invention to complete trajectory control. Compare the inland river ship trajectory control effects of the traditional guidance law LOS and the guidance law ILOS based on drift angle compensation proposed by the present invention under the conditions of no environmental disturbance and the presence of wind and current disturbances. As Figure 10 shown, the comparison between LOS (traditional trajectory control) and ILOS (improved type). Figure 10 (a), the trajectory of ILOS is closer to the target path, with a maximum lateral deviation of only 5 meters, while LOS has a deviation of 15 meters during turning. The trajectory error ( Figure 10 (b), where the ordinate track error represents the trajectory error) shows that the error of ILOS stabilizes at ±2 meters after 500 seconds, while the error of LOS continues to oscillate. In terms of the commanded rudder angle ( Figure 10 (c), where rudder represents the commanded rudder angle), ILOS outputs a smoother rudder angle command by fusing the adaptive parameters of heading control, avoiding the high-frequency oscillation in the LOS method and improving the stability of trajectory tracking and ship maneuverability.

[0057] To quantitatively analyze the differences between the guidance law ILOS and the traditional guidance law LOS without drift angle compensation, the root mean square of the trajectory control errors at a propeller speed of 120 rpm and under different guidance laws is recorded in Table 3; Table 3 It can be seen from Table 3 that during the entire heading control process, compared with the traditional guidance law LOS without drift angle compensation, the guidance law ILOS proposed by the present invention has improved control accuracy and significantly reduced trajectory errors under the same simulation conditions. It can be seen that ILOS has stronger disturbance rejection ability and can still maintain high control accuracy and stability when facing external environmental factors such as wind and current, which is crucial for the safety and efficiency of inland river ships during actual navigation and significantly improves the maneuverability of the ship.

[0058] In one or more of the technical solutions in the embodiments of the present invention, a guidance law can be obtained by adding drift angle compensation to the initial heading command. This guidance law fully considers the dynamic characteristics of inland river ships in complex environments. Especially when facing external disturbances such as water flow and wind, it can significantly improve the accuracy and stability of heading control. The compensation of the drift angle not only optimizes the ship's navigation trajectory but also effectively reduces the heading deviation caused by environmental factors. In practical applications, this guidance law can ensure that inland river ships maintain the expected heading under various working conditions, thus greatly improving the safety and efficiency of navigation. Furthermore, the parameter control method is improved according to the second-order system of inland river ships, and combined with parameter adaptive control, the control parameters can be dynamically adjusted according to the actual operating state of the ship, further enhancing the robustness and adaptability of the system.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An inland ship active disturbance rejection control method based on guidance law and parameter adaptation, characterized in that: include: S1, determining the heading control strategy of the inland river vessel, analyzing the lateral displacement data of the inland river vessel to obtain the drift angle of the inland river vessel, and performing drift angle compensation on the heading control strategy to obtain the guidance law, specifically: ,in, Indicates heading instruction. It represents the angle between the track segment and the true north direction. Indicates the track deviation. represents the forward-looking vector, Indicates the lateral speed signal of an inland vessel, Indicates the speed of inland vessels; S2, design a parameter adaptive strategy for the controller of an inland vessel, the parameter adaptive strategy is ,in, Represents the first parameter of the controller, Indicates the second parameter of the controller, represents the rotation index, It represents the rudderability index; S3, the control system of the inland river vessel adjusts the navigation state of the inland river vessel according to the guidance law and the parameter adaptive strategy.

2. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 1 is characterized in that: The S1 step includes: The guidance law adopts the straight line of sight navigation algorithm and sets the starting waypoint of the inland ship as , set the first target waypoint of inland vessels to , set the second target waypoint of the inland river ship to , then the first target track of inland river ships is , the second target track of inland river vessels is , Set the current position of the inland river vessel when traveling on the first target track to , at this time is the angle between the first target track segment and the true north direction, and the calculation method is: ; Calculate the track deviation of the inland vessel at the current position for The spatial meaning of track deviation is the vertical distance from the current position of the inland vessel to the first target track segment.

3. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 2 is characterized in that: Step S1 also includes: The initial heading instruction of the inland ship is designed according to the track deviation: , in, Indicates the initial heading instruction, Represents the forward-looking vector.

4. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 3 is characterized in that: Step S1 also includes: The inland river vessel has a tracking differentiator module, which obtains the lateral displacement data of the inland river vessel during actual navigation, inputs the lateral displacement data into the tracking differentiator module, and then the tracking differentiator module outputs a lateral speed signal ; Get the ship speed of inland vessels , based on the lateral velocity signal The drift angle of inland river vessels can be calculated as ; By adding the drift angle compensation to the initial heading command, the heading command of the guidance law can be obtained as .

5. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 1 is characterized in that: The S2 step includes: The controller of the inland river vessel is a second-order system, and the time-domain differential equation of the second-order system is: ,in, represents the heading angular velocity, i.e. the turning rate, is the heading acceleration, represents the rotation index, represents the rudderability index, Represents the rudder angle; Assuming the initial condition is zero, the transfer function obtained after Laplace transform is: in, is the natural frequency of the system, is the system damping ratio, represents the Laplace variable; According to the comparison between the time domain differential equation and the transfer function, we can conclude , Set the system damping ratio , the controller gain is .

6. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 1 is characterized in that: The propeller speed of the inland river vessel is 60 rpm to 120 rpm.

7. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 1 is characterized in that: Step S3 also includes conducting a simulation test of the heading and track control of inland vessels based on the MATLAB simulation platform.

8. The inland ship active disturbance rejection control method based on guidance law and parameter adaptation according to claim 7 is characterized in that: Also includes: The simulation model of inland river vessels, environmental disturbance model, heading control module and track control module are constructed on the MATLAB simulation platform to carry out simulation tests on the heading control of inland river vessels at different speeds and the track control under the influence of wind disturbance.

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