CN-122015859-A - Under-actuated AUV event trigger cooperative path tracking control method based on self-adaptive fixed time disturbance observer

CN122015859ACN 122015859 ACN122015859 ACN 122015859ACN-122015859-A

Abstract

The invention provides an under-actuated AUV event triggering cooperative path tracking control method based on a self-adaptive fixed time disturbance observer, belongs to the technical field of underwater vehicles, designs a distributed fixed time cooperative guidance law based on a fluid coordinate system, realizes cooperation of AUVs on path parameters and expected speeds by combining a fixed time line-of-sight guidance method and a fixed time cooperative path parameter updating law, and provides a kinematic basis for AUV formation cooperative path tracking. The invention also introduces a self-adaptive fixed time disturbance observer to estimate the composite disturbance consisting of external disturbance and model uncertainty in fixed time, avoids the problem that the traditional disturbance observer is often based on the pre-condition of disturbance upper bound known, designs a fixed time integral sliding mode dynamics control law based on the composite disturbance compensation, realizes fixed time dynamics control, and designs a switch threshold event triggering mechanism to reduce communication burden. Compared with the traditional control method, the method has better convergence performance and control precision.

Inventors

DING WENJUN
Zhang Guozong
Huang Fengtianyi
ZHU PENGFEI
MAO ZHAOYONG
TIAN WENLONG
LIU YI
ZHAO PENGCHENG

Assignees

西北工业大学

Dates

Publication Date: 20260512
Application Date: 20260210

Claims (10)

1. An under-actuated AUV event triggering cooperative path tracking control method based on an adaptive fixed time disturbance observer is characterized by comprising the following steps: Step 1, an under-actuated AUV kinematic model and a dynamics model containing composite disturbance are established, wherein the composite disturbance is the sum of unknown external environment disturbance and unknown model internal uncertainty; Step 2, defining a directed graph for describing the communication topological relation among multiple AUVs in the AUV formation based on the expected cooperative path and the AUV formation configuration; step 3, designing a distributed fixed time collaborative guidance law by combining sight guidance and collaborative path parameter updating law based on the kinematic model and the directed graph in a three-dimensional space coordinate system, and calculating the guidance speed; step 4, based on the dynamics model, taking the disturbance value of which the upper bound is estimated to be unknown in fixed time as a target, designing a self-adaptive fixed time disturbance observer, calculating error dynamics of the self-adaptive fixed time disturbance observer, and estimating the value of the composite disturbance; And 5, designing a fixed time integral sliding mode dynamics control law and a switching threshold event trigger mechanism cooperated with the fixed time integral sliding mode dynamics control law based on the guidance speed calculated in the step 3 and the composite disturbance estimated value estimated in the step 4, wherein the switching threshold event trigger mechanism triggers the fixed time integral sliding mode dynamics control law to update when the dynamics control output error is above a set threshold value, so that the fixed time cooperated path tracking control of underactuated AUV formation is realized.
2. The under-actuated AUV event-triggered collaborative path tracking control method according to claim 1, wherein step 3 specifically comprises the steps of: Step 3.1 combining the first based on the kinematic model in step 1 Describing an underactuated AUV formation configuration by using a three-dimensional space reference coordinate system of the AUV, and defining a first AUV The three-dimensional space coordinate system comprises a Serset-Fernet coordinate system, a fluid coordinate system and a fixed coordinate system; Step 3.2 based on the first step Calculating the tangential angle in a given path of the underactuated AUV by utilizing the coordinate transformation relation between different coordinate systems in the three-dimensional space coordinate system Tracking error of three-dimensional path of underactuated AUV; And 3.3, designing a three-dimensional fixed time guidance law based on the three-dimensional path tracking error, designing a fixed time cooperative path parameter updating law based on the directed graph, obtaining a distributed fixed time cooperative guidance law based on the fixed time cooperative path parameter updating law and the three-dimensional fixed time guidance law, and obtaining the guidance speed of each underactuated AUV.
3. The underactuated AUV event triggered collaborative path tracking control method of claim 2, wherein in step 3.3, the derivative term of the guidance speed is obtained by designing the following fixed time filter: Wherein the method comprises the steps of 、、 Respectively represent the first AUV (autonomous Underwater vehicle) A channel(s), A channel(s), The filtering error of the channel is determined, 、、 Representing the filtered output 、、 With respect to the derivative of time, 、、、、、、、、 A positive constant is indicated and a positive constant is indicated, Indicating a positive constant greater than 0 and less than 1, Indicating a positive constant greater than 1.
4. The under-actuated AUV event-triggered collaborative path tracking control method according to claim 1, wherein step 4 specifically comprises the steps of: Step 4.1, reconstructing the dynamic model in the step 1; Step 4.2, based on the reconstructed dynamics model, taking the disturbance value of which the upper bound is estimated to be unknown in the fixed time as a target, designing a self-adaptive fixed time disturbance observer, calculating the error dynamics of the self-adaptive fixed time disturbance observer, and adjusting and optimizing the self-adaptive fixed time disturbance observer based on the error dynamics; And 4.3, estimating the composite disturbance encountered by the underactuated AUV formation control by using a self-adaptive fixed-time disturbance observer based on the actual speed and power output of the underactuated AUV, and obtaining an estimated value of the composite disturbance.
5. The method of claim 4, wherein in step 4.2, the expression of the adaptive fixed-time disturbance observer is: The error dynamic is expressed as: Wherein the method comprises the steps of The error function of the design is represented, Representing error functions of a design Is used for the purpose of determining the derivative of (c), Represented AUV velocity vector in body coordinate system With respect to the derivative of time, Representing an inertia matrix of the device, Representing the velocity vector of the AUV in the body coordinate system, Representing the approximate kinetic function of the design, Representing the derivative of the time of the approximate kinetic function, Representing the output of the AUV dynamics control, Representing composite disturbances Is used for the estimation of the (c), Representing composite disturbances Is used to estimate the error of the (c) signal, Indicating a positive constant greater than 0 and less than 1, Representing a positive constant greater than 1, Representing the upper bound of the composite disturbance Is used for the estimation of the (c), 、、、、、、 Representing a positive constant.
6. The under-actuated AUV event-triggered collaborative path tracking control method according to claim 1, wherein step 5 specifically comprises the steps of: Step 5.1, obtaining a speed integral error based on the guidance speed and the actual speed calculated in the step 3, and designing an integral sliding mode surface based on the speed integral error; Step 5.2, designing a fixed time integral sliding mode dynamics control law based on the integral sliding mode surface and the composite disturbance estimated value obtained in the step 4; step 5.3, designing a switch threshold event trigger mechanism to realize the switching of a fixed time integral sliding mode dynamics control law between the fixed threshold event trigger mechanism and a relative threshold event trigger mechanism; and 5.4, triggering the updating of the fixed-time integral sliding mode dynamics control law when the dynamics control output error is above a set threshold value.
7. The underactuated AUV event-triggered collaborative path tracking control method of claim 6, wherein in step 5.2, the expression of the fixed time integral sliding mode dynamics control law is: Wherein the method comprises the steps of 、、 Respectively represent the first Before the AUV event trigger mechanism A channel(s), A channel(s), The dynamics of the channel control the output, 、、 Respectively shown in A channel(s), A channel(s), The inertia vector on the channel is set to be, 、、 Respectively represent designed A channel(s), A channel(s), The sliding mode surface of the channel is provided with a sliding mode surface, 、、 Respectively represent the desired speed of the distributed cooperative guidance law 、 A channel(s), The output of the channel is provided with a signal, 、、 Respectively represent Composite disturbance estimates for channel, q-channel, r-channel, 、、 Respectively represent A channel(s), A channel(s), The velocity of the channel integrates the error derivative, 、、、、、、、、、、、 Representing a constant.
8. The method of claim 7, wherein in step 5.3, the fixed threshold event trigger mechanism is satisfied by , , The dynamics control output of each channel is set as follows: Relative threshold event trigger mechanism, satisfy , , The dynamics control output of each channel is set as follows: Wherein the method comprises the steps of 、、 Respectively represent A channel(s), A channel(s), The dynamics of the channel over time control the output, 、、 A positive constant is indicated and a positive constant is indicated, 、、 Respectively represent A channel(s), A channel(s), The dynamics control output of the channel at a fixed threshold time trigger, 、、 Respectively represent A channel(s), A channel(s), The channel triggers a dynamics control output at a relative threshold event, 、、、、、、、、 Representing an arbitrary time-varying continuous function with an absolute value less than 1, 、、、、、、、、 Representing a positive constant.
9. The underactuated AUV event-triggered collaborative path tracking control method of claim 8, wherein in step 5.4, the fixed time integral sliding mode dynamics control law is updated according to the following settings: Wherein the method comprises the steps of 、、 Respectively represent A channel(s), A channel(s), The dynamics of the channel control the output error, An input update time representing a dynamics control law, the dynamics control law being to be when the dynamics control output error is above a corresponding threshold The dynamics output value is updated at the moment.
10. The underactuated AUV event-triggered collaborative path tracking control method of claim 2, wherein the guidance command parameters in the three-dimensional fixed time guidance law in step 3.3 include a synthetic velocity Pitch angle rate Yaw rate of angular velocity Track angle And azimuth angle 。

Description

Under-actuated AUV event trigger cooperative path tracking control method based on self-adaptive fixed time disturbance observer Technical Field The invention belongs to the technical field of underwater vehicles, and particularly relates to an under-actuated AUV event triggering cooperative path tracking control method based on a self-adaptive fixed time disturbance observer. Background With the continuous development of ocean technology in various countries, automatic Underwater Vehicles (AUV) have been applied to various fields such as underwater target detection, deep sea resource investigation, and submarine surveying and mapping. The developed AUV has the advantages of flexible maneuverability, good concealment and the like, and due to the limited capacity of a single AUV, the recently developed technology for forming a formation and executing tasks by utilizing a plurality of AUVs can fully improve the detection performance of the plurality of AUVs. Two types of disturbance influence are usually encountered in the task execution process of multiple AUV formation, wherein the first type is external environment disturbance such as impact force generated by wind, sea wave, ocean current and the like on the AUV, and the second type is AUV internal disturbance such as AUV formation internal disturbance caused by unmodeled dynamics and parameter uncertainty. Since the hydrodynamic model of the AUV is based on commercial fluid calculation software or pool experimental measurements, model uncertainty is unavoidable. Moreover, although the two types of disturbance do not necessarily exist at the same time, the stability and the effectiveness of the control system are negatively affected, and the disturbance value cannot be directly measured by using a sensor. Based on these adverse factors, the accuracy of multi-AUV formation motion control will be directly affected, and therefore the disturbances described above need to be handled in the AUV control design. In a complex marine environment, the anti-interference control has important engineering significance for normal navigation of the AUV. The disturbance observer is used as an effective method for estimating and compensating unknown disturbance, and the core idea is to consider the uncertainty and disturbance of the system as a composite disturbance, and then rapidly and accurately estimate the composite disturbance by using the disturbance observer, thereby realizing the compensation of the system state. At present, a traditional disturbance observer is often designed based on the condition that the disturbance upper bound is known as a precondition, and only meets asymptotically stable conditions, so that the disturbance observer cannot be well adapted to high-performance control of a plurality of AUVs in a marine environment. Meanwhile, underwater communication resources are limited, and stable communication of a plurality of AUVs for a long time cannot be met. Disclosure of Invention The invention aims to solve the problems that the traditional disturbance observer in the prior art depends on the known disturbance upper bound, can only realize asymptotic stability and is difficult to meet the high-performance control requirement of a multi-AUV system in a marine environment, and provides an under-actuated AUV event triggering cooperative path tracking control method based on a self-adaptive fixed time disturbance observer. And introducing estimated composite disturbance, performing disturbance compensation based on the estimated composite disturbance, designing a fixed time integral sliding mode dynamics control law, realizing fixed time dynamics control, and introducing a switching threshold event trigger mechanism to reduce communication burden. In order to achieve the above purpose, the technical solution provided by the present invention is: The invention provides an underactuated AUV event triggering cooperative path tracking control method based on a self-adaptive fixed time disturbance observer, which comprises the following steps: step 1, an under-actuated AUV kinematic model and a dynamics model containing composite disturbance are established, wherein the composite disturbance is the sum of unknown external environment disturbance and the internal uncertainty of the unknown model; Step 2, defining a directed graph for describing the communication topological relation among multiple AUVs in the AUV formation based on the expected cooperative path and the AUV formation configuration; Step 3, designing a distributed fixed time collaborative guidance law based on a kinematic model and a directed graph and combining with line-of-sight guidance and collaborative path parameter updating law under a three-dimensional space coordinate system, and calculating the guidance speed; Step 4, based on a dynamics model, taking a disturbance value of which the upper bound is estimated to be unknown in a fixed time as a target, designing a self-adaptive fixed t