Thrust distribution method of underwater operation robot, electronic equipment and medium

Abstract

The invention relates to a thrust distribution method of an underwater operation robot, electronic equipment and a medium. Comprising the following steps: establishing an underwater operation robot body coordinate system; determining a vector arrangement matrix according to the position layout parameters of the horizontal plane propeller and the vertical plane propeller, and calculating the theoretical maximum thrust and torque; the thrust and the torque are divided into a horizontal plane and a vertical plane, and the initial thrust or torque is calculated through the output control quantity of the controller; calculating an additional moment and an additional thrust according to the influence of the decoupled thrust on the opposite surface; subtracting the corresponding additional thrust or additional torque from the initial thrust or torque to obtain comprehensive thrust or comprehensive torque to be distributed; according to the comprehensive thrust or the comprehensive torque, thrust distribution results of the horizontal plane propeller and the vertical plane propeller are calculated respectively. According to the method, the calculation of thrust distribution is simplified, and the thrust coupling of the horizontal plane and the vertical plane of the ROV is considered, so that the final thrust distribution result conforms to the expected motion state of the ROV.

Description

Technical Field

[0001] The present invention belongs to the field of underwater working robot control, and in particular relates to a thrust distribution method, electronic equipment and medium of an underwater working robot. Background Art

[0002] As the shortage of land resources and energy depletion become increasingly serious, opening up new ways to obtain resources is an unavoidable issue. The ocean is rich in resources such as oil, gas, and minerals. Therefore, the exploration and development of marine resources is an important way to solve the shortage of land resources. The operational remote-controlled underwater operation robot (ROV) can complete high-intensity, high-load and high-precision operations in the deep-sea environment, and is one of the major technical equipment indispensable for the exploration and development of deep-sea resources. Generally, for deep-sea operation ROVs, in order to ensure the ROV's underwater six-degree-of-freedom operation capability, the ROV body is equipped with 7 or 8 vector-arranged thrusters to provide power for the ROV movement. The ROV six-degree-of-freedom motion control requires reasonable and effective control of these 7 or 8 thrusters to enable the ROV to achieve the desired motion state. How to reasonably and effectively control these 7 or 8 thrusters so that the ROV can reach the desired motion state is the problem to be solved by the thrust distribution method. Therefore, the thrust distribution method is particularly important for the motion control of the ROV. However, the current thrust distribution method for this underwater operation robot has the following problems:

[0003] First, the problem of thrust output saturation. At present, the most widely used and representative thrust distribution method in practical engineering is the pseudo-inverse method and its improved algorithm. However, this thrust distribution method does not take into account the output capacity of the thruster, which may cause the output thrust of the thruster to exceed its output capacity range, which leads to the problem of thrust output saturation. In addition, even some thrust distribution methods that have been proposed to avoid the problem of saturated output, such as mathematical programming method, intelligent allocation algorithm and other optimization algorithms, have complex calculation process, large amount of calculation, and insufficient real-time performance. Or even if the algorithm proposed at present is simple to calculate and can avoid the problem of saturated output, there are some empirical parameters such as weight coefficients or amplification coefficients to be determined during the implementation of the algorithm. These parameters are subjective and need to be confirmed by technicians with relevant experience, which undoubtedly limits the scope of use of the algorithm.

[0004] Secondly, the thrust distribution method has a complex calculation process. At present, the common ROV propulsion distribution methods include pseudo-inverse distribution method and its improved algorithm, mathematical programming method, intelligent distribution algorithm, etc. In practical application, the calculation process of these distribution algorithms is complicated to a certain extent, with large amount of calculation and insufficient real-time performance. This is not conducive to practical engineering with high real-time requirements. Therefore, in order to simplify the thrust distribution calculation process and improve the real-time performance of the calculation, it is of great engineering significance to develop a thrust distribution calculation method with simple calculation. The pseudo-inverse distribution method does not need to consider the execution capacity range and position saturation constraints, and the calculation results will not be consistent with the actual expectations, and there will be problems such as thruster saturation and deficiency. The mathematical programming method is more complicated to solve the optimal problem, the calculation speed is slow, and there may be insufficient real-time performance. The method has the problem that iteration at the local extreme point cannot converge to the global optimum, and due to the relaxation of the restriction conditions during the solution, the thrust after distribution may not achieve the expected effect.

[0005] Finally, there is the problem of thrust distribution accuracy. In order to simplify the thrust distribution of overdriven operational ROVs, some existing thrust distribution methods divide the ROV's thrusters into horizontal thrusters and vertical thrusters for decoupling control according to the plane of ROV motion during thrust distribution. Although this thrust distribution method reduces the dimensionality and design difficulty of the operational ROV motion control system and simplifies thrust distribution, the mutual influence between horizontal and vertical motion is ignored after decoupling the horizontal and vertical motions. This mutual influence is not considered in the thrust distribution and compensated for, resulting in the phenomenon that the motion state of the ROV does not match the actual expectations as a result of the thrust distribution. Summary of the invention

[0006] The present invention provides a thrust distribution method, electronic equipment and medium for an underwater working robot, the purpose of which is to solve the saturation problem of thrust output and simplify the calculation of thrust distribution, and to consider the thrust coupling between the horizontal and vertical surfaces of the ROV so that the final thrust distribution result conforms to the expected motion state of the ROV.

[0007] To achieve the above object, the present invention provides a thrust distribution method for an underwater working robot in a first aspect, comprising the following steps:

[0008] Establishing a main body coordinate system of the underwater working robot, wherein the main body coordinate system of the underwater working robot includes a longitudinal axis, a transverse axis and a vertical axis, and the origin of the coordinate system is located at the center of gravity of the underwater working robot;

[0009] According to the position layout parameters of the horizontal and vertical thrusters in the coordinate system of the underwater working robot, the vector layout matrices of the horizontal and vertical planes are determined respectively, and the theoretical maximum thrust and torque of each degree of freedom in each direction are calculated;

[0010] The thrust and torque of the underwater working robot are divided into the horizontal plane and the vertical plane, and the initial thrust or torque of the horizontal plane and the vertical plane are calculated through the output control quantity of the controller;

[0011] According to the influence of the decoupled thrust on the opposite surface, the additional moment of the horizontal thrust on the vertical surface and the additional thrust of the vertical surface moment on the horizontal surface are calculated respectively;

[0012] Subtract the corresponding additional thrust or additional torque from the initial thrust or torque on the horizontal plane and the vertical plane, respectively, to obtain the comprehensive thrust or comprehensive torque to be distributed;

[0013] According to the comprehensive thrust or comprehensive torque, the thrust distribution results of the horizontal and vertical thrusters are calculated respectively.

[0014] Furthermore, the horizontal plane vector arrangement matrix is ​​determined by the following thrust equation:

[0015]

[0016] The vertical plane vector arrangement matrix is ​​determined by the following thrust equation:

[0017]

[0018] In formula (1): x For along O b X b Longitudinal thrust of the shaft, τ y O b Y b Transverse thrust of the shaft, τ N For around O b Z b The yaw moment of the axis, A is the horizontal plane vector arrangement matrix, T1 is the output thrust of the 1# thruster, T2 is the output thrust of the 2# thruster, T3 is the output thrust of the 3# thruster, and T4 is the output thrust of the 4# thruster;

[0019] In formula (2): Z For along O b Z b Axis lifting thrust, τ R For around O b X b Heeling moment of the axis, τ p For around O b Y b The longitudinal tilt moment of the axis, B is the vertical plane vector arrangement matrix, T5 is the output thrust of the 5# thruster, T6 is the output thrust of the 6# thruster, T7 is the output thrust of the 7# thruster, and T8 is the output thrust of the 8# thruster.

[0020] Furthermore, the method for calculating the theoretical maximum thrust and moment of each degree of freedom in each direction includes:

[0021] According to the following relationship, the relationship between the thrust or torque and the control quantity of each degree of freedom in the horizontal and vertical planes is constructed respectively:

[0022]

[0023] In formula (3): T xmax , T ymax , T Nmax are the maximum longitudinal force, maximum lateral force and maximum yaw moment corresponding to single free motion, u xmax 、u ymax 、u Nmax are the control quantities corresponding to the maximum longitudinal thrust, maximum lateral thrust and maximum yaw moment, respectively, u x 、u y 、u N are the control quantities corresponding to the initial longitudinal thrust, initial lateral thrust and initial yaw moment output by the underwater robot operator or controller at the current moment, T x1 , T y1 , T N1 They are the initial longitudinal thrust, initial lateral thrust and initial yaw moment of the underwater working robot at the current moment;

[0024] In formula (4): T zmax , T Rmax , T Pmax They are the maximum lifting force, maximum heeling moment and maximum pitching moment during single free motion; u zmax 、u Rmax 、u Pmax are the control quantities corresponding to the maximum lifting force, the maximum heeling moment and the maximum pitching moment respectively; u z 、u R 、u P are the control quantities corresponding to the initial lifting force, initial heel moment and initial pitch moment output by the underwater robot operator or controller at the current moment; T z1 , T R1 , T P1 They are the initial lifting force, initial heel moment and initial pitch moment of the underwater working robot at the current moment respectively;

[0025] For formula (3), the maximum longitudinal force, maximum lateral force and maximum yaw moment on the horizontal plane are calculated according to the following formulas:

[0026]

[0027] In formula (5): T hA is the rated thrust of the horizontal thruster; 11 , A 21 , A 31 Arrange the three elements of the first column of the matrix for the established horizontal plane vectors respectively;

[0028] For formula (4), the maximum lift force, maximum heel moment and maximum pitch moment on the vertical plane are calculated according to the following formulas:

[0029]

[0030] In formula (6): T v is the rated thrust of the vertical thruster, B 11 , B 21 , B 31 The three elements of the first column of the matrix are arranged for the established perpendicular plane vectors respectively.

[0031] Furthermore, according to the influence of the decoupled thrust on the opposite surface, the method of respectively calculating the additional moment of the horizontal thrust on the vertical surface and the additional thrust of the vertical surface moment on the horizontal surface includes:

[0032] Determine the initial longitudinal thrust and initial lateral thrust in the horizontal plane;

[0033] Determine the distance parameter between the horizontal plane thruster and the center of gravity of the underwater operation robot;

[0034] The initial longitudinal thrust, initial lateral thrust and distance parameters are used to calculate the pitch moment and heel moment exerted on the vertical plane by the initial longitudinal thrust and initial lateral thrust on the horizontal plane.

[0035] Determine the initial thrust of the vertical plane and its relative position parameters to the horizontal plane;

[0036] Calculate the lateral thrust exerted on the horizontal plane by the initial heeling moment and the initial pitching moment on the vertical plane.

[0037] Furthermore, the calculation formulas for the pitch moment, heel moment and lateral thrust are as follows:

[0038]

[0039] In formula (7): is the heeling moment; is the pitch moment; is the lateral thrust; T x1 is the initial longitudinal thrust; T y1 is the initial lateral thrust; T P1 is the initial pitch moment; T R1 is the initial heeling moment; z hx is the distance from the origin of the underwater robot's coordinate system to the axis of the horizontal propeller; v is the distance from the vertical thruster to the x-axis of the underwater robot's coordinate system; v is the distance from the vertical thruster to the y-axis of the underwater working robot's body coordinate system; β is the angle between the vertical thruster and the positive z-axis of the underwater working robot's body coordinate system.

[0040] Furthermore, the calculation formula for the comprehensive thrust or torque to be distributed is as follows:

[0041]

[0042] In formula (8): T x1 is the initial longitudinal thrust; T x is the comprehensive longitudinal thrust; T y1 is the initial lateral thrust; is the initial heeling moment T on the vertical plane R1 With the initial pitch moment T P1 Transverse thrust applied to the horizontal plane; T y is the comprehensive lateral thrust; T N1 is the initial yaw moment, T N is the integrated yaw moment;

[0043] In formula (9): T Z1 is the initial lifting force; T z is the comprehensive lifting force; T R1 is the initial heeling moment; is the initial thrust T on the horizontal plane y1 Heeling moment applied to the vertical surface; T R is the comprehensive heeling moment; T P1 is the initial pitch moment, is the pitch moment exerted by the initial thrust on the horizontal plane on the vertical plane, T P is the comprehensive pitch moment.

[0044] Furthermore, the calculation method of the thrust distribution result of the horizontal plane thruster includes:

[0045] The comprehensive longitudinal force, comprehensive lateral force and comprehensive yaw moment of the horizontal plane are decomposed respectively to obtain the thrust expression of each thruster on the horizontal plane:

[0046]

[0047] In formula (10): T x is the comprehensive longitudinal thrust; T y is the comprehensive lateral thrust; T N is the comprehensive yaw moment; A ij(i=1,2,3,4;j=1,2,3,4) are the elements of the established horizontal plane vector arrangement matrix, and T1, T2, T3, and T4 are the output thrusts of the four thrusters on the horizontal plane after thrust distribution.

[0048] Furthermore, the calculation method of the thrust distribution result of the vertical thruster includes:

[0049] The lift force, heel moment and pitch moment of the vertical plane are decomposed respectively to obtain the thrust expression of each thruster in the vertical plane:

[0050]

[0051] In formula (11): T z is the comprehensive longitudinal thrust, T R is the comprehensive lateral thrust, T P is the comprehensive yaw moment, B ij (i=1,2,3,4;j=1,2,3,4) are the elements of the established vertical plane vector arrangement matrix, and T5, T6, T7 and T8 are the output thrusts of the four thrusters in the vertical plane after thrust distribution.

[0052] To achieve the above-mentioned purpose, the second aspect of the present invention provides an electronic device, including a processor and a memory, wherein the processor is used to implement the steps of the thrust distribution method of the underwater working robot when executing a computer program stored in the memory.

[0053] To achieve the above-mentioned purpose, the third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the thrust distribution method of the underwater working robot.

[0054] Beneficial effects of the present invention:

[0055] Compared with the prior art, the thrust distribution method, electronic device and medium of an underwater working robot provided by the present invention realize the limitation of the thrust output of the propeller within its capability range by reconstructing the relationship between the thrust expected to be output in each degree of freedom of the ROV and its corresponding control quantity, and solve the problem of thrust output saturation. Specifically, the method not only considers the relationship between the thrust and the control quantity of a single degree of freedom, but also introduces the coupling effect between the related degrees of freedom, thereby effectively avoiding the overload of the propeller in multi-degree-of-freedom motion. At the same time, by decomposing the six-degree-of-freedom motion of the ROV into horizontal and vertical plane motions and decoupling them respectively, and then combining the vector arrangement matrix to derive the general thrust distribution formula, the calculation process is greatly simplified and the complexity of real-time calculation is reduced. In addition, the present invention ensures that the motion state of the ROV after thrust distribution meets expectations by calculating and compensating for the additional force or torque generated by the coupling between the horizontal and vertical plane motions, and significantly improves the accuracy and precision of thrust distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0057] Figure 1 It is a schematic diagram of a body coordinate system of an operational ROV disclosed in an embodiment of the present invention.

[0058] Figure 2 It is a schematic diagram of the arrangement of four horizontal thrusters disclosed in an embodiment of the present invention.

[0059] Figure 3 It is a schematic diagram of the arrangement of four vertical thrusters disclosed in an embodiment of the present invention.

[0060] Figure 4 It is a simplified diagram of the implementation steps of an operational thrust distribution disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0061] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0062] According to an embodiment of the present invention, it should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0063] like Figure 1-Figure 4 As shown, the present invention provides a thrust distribution method for an underwater working robot, the method comprising the following steps:

[0064] Step S100, establishing a main body coordinate system of the underwater working robot, wherein the main body coordinate system of the underwater working robot includes a longitudinal axis, a transverse axis and a vertical axis, and the origin of the coordinate is located at the center of gravity of the underwater working robot;

[0065] Step S200, according to the position layout parameters of the horizontal and vertical thrusters in the coordinate system of the underwater working robot body, respectively determine the vector layout matrices of the horizontal and vertical planes, and calculate the theoretical maximum thrust and torque of each degree of freedom in each direction;

[0066] Step S300, dividing the thrust and torque of the underwater working robot into the horizontal plane and the vertical plane, and calculating the initial thrust or torque of the horizontal plane and the vertical plane through the output control quantity of the controller;

[0067] Step S400, according to the influence of the decoupled thrust on the opposite surface, respectively calculating the additional moment of the horizontal thrust on the vertical surface and the additional thrust of the vertical surface moment on the horizontal surface;

[0068] Step S500, subtracting the corresponding additional thrust or additional torque from the initial thrust or torque of the horizontal plane and the vertical plane respectively to obtain the comprehensive thrust or comprehensive torque to be distributed;

[0069] Step S600: Calculate thrust distribution results of the horizontal and vertical thrusters respectively according to the comprehensive thrust or comprehensive torque.

[0070] This embodiment solves the thrust output saturation problem by reconstructing the relationship between the thrust (torque) expected to be output by each degree of freedom of the ROV and the control quantity, and ensures that the thruster works normally within its capacity. At the same time, the six-degree-of-freedom motion is decomposed into horizontal and vertical plane motion for decoupling, and a simplified thrust distribution expression is derived in combination with the vector arrangement matrix, thereby greatly reducing the computational complexity and improving real-time performance. In addition, by compensating for the additional force or torque generated during the decoupling process, the accuracy of thrust distribution is guaranteed, so that the actual motion state of the ROV meets expectations. This method not only improves the efficiency and accuracy of thrust distribution, but also enhances the reliability and response speed of the system.

[0071] In step S100, the underwater operation robot (ROV) of this embodiment is equipped with eight thrusters, four of which are horizontal and four are vertical. Figure 1 The ROV body coordinate system O shown b -X b Y b Z b , the origin of the coordinate system is located at the center of gravity of the ROV, and the longitudinal axis O b X b Along the bow of the underwater working robot pointing forward, the horizontal axis O b Y b Perpendicular to the longitudinal axis O b X b Pointing to the starboard side of the underwater operation robot, the longitudinal axis O b X b With horizontal axis O b Y b Constitute the horizontal base surface of the underwater operation robot; b Z b Point to the bottom of the underwater working robot and are respectively aligned with the longitudinal axis O b X b , horizontal axis O b Y b The underwater robot can move in six degrees of freedom, namely along O b X b The longitudinal movement of the axis along O b Y b Transverse movement of the axis, along O b Z b The lifting motion of the axis, around O b X b Heeling motion of axis rotation, around O b Y b Pitch motion of the axis, around O b Z b Yaw motion of the axis.

[0072] In step S200, the four thrusters on the horizontal plane control the longitudinal, lateral and yaw motions of the underwater working robot. The four thrusters on the horizontal plane are the same, and the rated thrust of each thruster is T H Newton. The arrangement of the four thrusters on the horizontal plane is as follows Figure 2 As shown, two horizontal thrusters are installed at the front of the underwater working robot and connected to the O of the underwater working robot. b X b The angles of the positive directions of the axes are all α, and the other two horizontal thrusters are installed at the rear of the underwater working robot and at the same angle as the O axis of the underwater working robot. b X bThe angles in the opposite directions of the axes are all α. The four horizontal thrusters are located below the center of gravity of the underwater working robot. The distance from the center of gravity of the underwater working robot to the axis of the horizontal thrusters is z. h , the distances from the four thrusters on the horizontal plane to the x-axis and y-axis are x h ,y h From the position parameters of the above-mentioned horizontal thruster arrangement, the horizontal vector arrangement matrix can be obtained. Assuming that the horizontal vector arrangement matrix is ​​A, the horizontal thrust equation is:

[0073]

[0074] In formula (1): x For along O b X b Longitudinal thrust of the shaft, τ y O b Y b Transverse thrust of the shaft, τ N For around O b Z b The yaw moment of the axis, A is the horizontal plane vector arrangement matrix, T1 is the output thrust of the 1# thruster, T2 is the output thrust of the 2# thruster, T3 is the output thrust of the 3# thruster, and T4 is the output thrust of the 4# thruster;

[0075] The four thrusters on the vertical plane control the lifting, heeling and pitching movements of the underwater operation robot. The four thrusters on the vertical plane are the same, and the rated thrust of each thruster is T v Newton. The arrangement of the four thrusters on the vertical plane is as follows Figure 3 As shown, two vertical thrusters are installed at the front of the underwater working robot and are connected to the O b -Y b Z b The other two vertical thrusters are installed at the rear of the underwater working robot and are also parallel to the O of the underwater working robot. b -Y b Z b The installation axis of the four vertical thrusters is parallel to the O b Z b The angles of the axes are all β, the four vertical thrusters are located above the center of gravity of the underwater working robot, and the distance from the center of gravity of the underwater working robot to the axis of the vertical thrusters is z v , the distances from the four thrusters in the vertical plane to the x-axis and y-axis are x v ,y v From the above position parameters of the vertical thruster arrangement, the vertical vector arrangement matrix can be obtained. Assuming that the vertical vector arrangement matrix is ​​B, the vertical thrust equation is:

[0076]

[0077] In formula (2): Z For along O b Z b Axis lifting thrust, τ R For around O b X b Heeling moment of the axis, τ p For around O b Y b The longitudinal tilt moment of the axis, B is the vertical plane vector arrangement matrix, T5 is the output thrust of the 5# thruster, T6 is the output thrust of the 6# thruster, T7 is the output thrust of the 7# thruster, and T8 is the output thrust of the 8# thruster.

[0078] Due to the characteristics of the vector layout of the propeller, there is a coupling effect between the movements of each degree of freedom. When there are two or three degrees of freedom thrust (torque) output at the same time in the horizontal or vertical plane, it is possible that the output thrust of a certain propeller exceeds its output capacity range, which leads to the saturation problem of thrust output. In the conventional thrust distribution method, the thrust or torque of each degree of freedom and its corresponding control quantity are in a purely linear proportional relationship, and the mutual influence and coupling effect between the movements of each degree of freedom are not considered at all. In order to avoid the output saturation problem, when determining the relationship between the thrust or torque of each degree of freedom and the control quantity, the present invention not only considers the relationship between the thrust or torque of a certain degree of freedom and its corresponding control quantity, but also considers the influence of other degrees of freedom that are coupled with this degree of freedom on it. Specifically, the relationship between the thrust or torque and the control quantity of each degree of freedom in the horizontal and vertical planes is constructed respectively according to the following relationship.

[0079]

[0080] In formula (3): T xmax , T ymax , T Nmax are the maximum longitudinal force, maximum lateral force and maximum yaw moment corresponding to single free motion, u xmax 、u ymax 、u Nmax are the control quantities corresponding to the maximum longitudinal thrust, maximum lateral thrust and maximum yaw moment, respectively, u x 、u y 、u N are the control quantities corresponding to the initial longitudinal thrust, initial lateral thrust and initial yaw moment output by the underwater robot operator or controller at the current moment, T x1 , T y1 , T N1 They are the initial longitudinal thrust, initial lateral thrust and initial yaw moment of the underwater working robot at the current moment;

[0081] In formula (4): T zmax , T Rmax , T Pmax They are the maximum lifting force, maximum heeling moment and maximum pitching moment during single free motion; u zmax 、u Rmax 、u Pmax are the control quantities corresponding to the maximum lifting force, the maximum heeling moment and the maximum pitching moment respectively; u z 、u R 、u P are the control quantities corresponding to the initial lifting force, initial heel moment and initial pitch moment output by the underwater robot operator or controller at the current moment; T z1 , T R1 , T P1 They are respectively the initial lifting force, initial heel moment and initial pitch moment of the underwater working robot at the current moment.

[0082] For T in formula (3) xmax , T ymax , T Nmax It can be calculated as follows:

[0083]

[0084] In formula (5): T h A is the rated thrust of the horizontal thruster; 11 , A 21 , A 31 They are respectively the three elements of the first column of the horizontal plane vector arrangement matrix A in the horizontal plane thrust equation established according to formula (1).

[0085] For T in formula (4) zmax , T Rmax , T Pmax It can be calculated as follows:

[0086]

[0087] In formula (6): T v is the rated thrust of the vertical thruster, B 11 , B 21 , B 31 They are respectively the three elements of the first column of the vertical plane vector arrangement matrix B in the vertical plane thrust equation established according to formula (2).

[0088] It can be seen from equations (3) and (4) that, in single-degree-of-freedom motion, the expected thrust (torque) is in a purely linear proportional relationship with the corresponding control quantity; when the motion state exceeds a single degree of freedom, the expected thrust (torque) of a certain degree of freedom is not only related to the corresponding control quantity, but also to the control quantities corresponding to the expected thrust (torque) of other degrees of freedom that have an impact on this degree of freedom, which fully reflects the coupling between the expected thrust (torque) corresponding to the degrees of freedom that have an impact on each other.

[0089] In order to simplify the thrust distribution, the thrusters of the ROV are divided into horizontal thrusters and vertical thrusters, which are decoupled and then controlled separately. However, in reality, there is coupling between the horizontal thrust and the vertical thrust. Therefore, the present invention performs corresponding compensation after decoupling to offset the additional force or torque caused by the decoupling, so that the motion state of the ROV is consistent with the actual expectation. According to the layout diagram of the horizontal and vertical thrusters ( Figure 2 and Figure 3 ) can be judged that the initial longitudinal thrust T of the horizontal plane after decoupling x1 , initial lateral thrust T y1 The pitch moment applied to the vertical surface Heeling moment Initial heeling moment T on the vertical plane R1 With the initial pitch moment T p1 The lateral thrust applied to the horizontal plane. The specific calculation formula is as follows:

[0090]

[0091] In formula (7): is the heeling moment; is the pitch moment; is the lateral thrust; T x1 is the initial longitudinal thrust; T y1 is the initial lateral thrust; T P1 is the initial pitch moment; T R1 is the initial heeling moment; z h x is the distance from the origin of the underwater robot's coordinate system (i.e., the center of gravity) to the axis of the horizontal propeller; v is the distance from the vertical thruster to the x-axis of the underwater robot's coordinate system; v is the distance from the vertical thruster to the y-axis of the underwater working robot's body coordinate system; β is the angle between the vertical thruster and the positive z-axis of the underwater working robot's body coordinate system.

[0092] It is understandable that in the present invention, the thruster of ROV is divided into a horizontal thruster and a vertical thruster, and this division allows them to be controlled separately, thereby simplifying the thrust distribution process. However, in fact, there is a coupling effect between the horizontal thrust and the vertical thrust. In order to ensure that the actual motion state of the ROV is consistent with expectations, the method offsets the additional force or torque caused by decoupling by compensation after decoupling. This means that the initial horizontal thrust (such as longitudinal and lateral thrust) will affect the vertical plane (such as pitch moment and roll moment), and vice versa. Therefore, by calculating these interactions and making corresponding compensation adjustments, the accuracy of thrust distribution can be improved, making the movement of the ROV more reliable and accurate.

[0093] Subtract the corresponding additional thrust / torque from the initial thrust / torque of the horizontal plane and the vertical plane to obtain the comprehensive thrust / torque of the horizontal plane and the vertical plane. The specific calculation formula is as follows:

[0094]

[0095] In formula (8): T x1 is the initial longitudinal thrust; T x is the comprehensive longitudinal thrust; T y1 is the initial lateral thrust; is the initial heeling moment T on the vertical plane R1 With the initial pitch moment T P1 Apply lateral thrust to the horizontal plane; T y is the comprehensive lateral thrust; T N1 is the initial yaw moment, T N is the integrated yaw moment;

[0096] In formula (9): T Z1 is the initial lifting force; T z is the comprehensive lifting force; T R1 is the initial heeling moment; is the initial lateral thrust T on the horizontal plane y1 Heeling moment applied to the vertical surface; T R is the comprehensive heeling moment; T P1 is the initial pitch moment, is the pitch moment exerted by the initial longitudinal thrust on the horizontal plane on the vertical plane, T P is the comprehensive pitch moment.

[0097] This process first identifies the additional forces or moments caused by decoupling, and then subtracts these additional values ​​from the initial thrust or moment in each direction (horizontal and vertical). The purpose of this is to ensure that the final thrust distribution accurately reflects the expected state of motion without being affected by errors that may be introduced during the decoupling process. For example, the initial longitudinal thrust in the horizontal plane may produce some roll or pitch moment in the vertical plane. By calculating and compensating for these additional moments, a more accurate combined thrust and torque can be obtained, thereby improving the overall control effect.

[0098] The comprehensive longitudinal force T on the horizontal plane x , comprehensive lateral force T y and the integrated yaw moment T N Decompose it and get the thrust expression of each thruster on the horizontal plane:

[0099]

[0100] In formula (10): T x is the comprehensive longitudinal thrust; T y is the comprehensive lateral thrust; T N is the comprehensive yaw moment; A ij (i=1,2,3,4;j=1,2,3,4) are the elements of the established horizontal plane vector arrangement matrix, and T1, T2, T3, and T4 are the output thrusts of the four thrusters on the horizontal plane after thrust distribution.

[0101] Similarly, the lifting force T on the vertical surface is z , heeling moment T R and the pitch moment T P Decompose it and get the thrust expression of each thruster in the vertical plane:

[0102]

[0103] In formula (11): T z is the comprehensive longitudinal thrust, T R is the comprehensive lateral thrust, T P is the comprehensive yaw moment, B ij (i=1,2,3,4;j=1,2,3,4) are the elements of the established vertical plane vector arrangement matrix, and T5, T6, T7 and T8 are the output thrusts of the four thrusters in the vertical plane after thrust distribution.

[0104] In the "Horizontal and Vertical Thrust Distribution" section, the compensated comprehensive thrust and torque are reasonably decomposed to determine the output thrust of each thruster. Specifically, this process involves decomposing the comprehensive longitudinal force, lateral force and yaw moment of the horizontal plane, and the lift force, roll moment and pitch moment of the vertical plane item by item. These comprehensive forces and moments are mapped to their corresponding thrusters, and the thrust value required to be generated by each thruster is obtained by using pre-defined vector arrangement matrices (horizontal plane matrix A and vertical plane matrix B). This method ensures that the various thrusters can work together to achieve the desired motion state of the ROV and effectively utilize their thrust capabilities.

[0105] The specific implementation steps of the present invention are as follows Figure 4 The detailed description is as follows:

[0106] The first step is to Figure 1 The ROV body coordinate system O shown b -X b Y b Z b , coordinate origin O b Located at the center of gravity of the ROV, the longitudinal axis O b X b Along the bow of the underwater robot pointing forward, the horizontal axis O b Y b Perpendicular to the longitudinal axis O b X b Pointing to the starboard side of the underwater robot, the vertical axis O b Z b point to the bottom of the underwater robot and are respectively aligned with the longitudinal axis O b X b , horizontal axis O b Y b Vertical, ROV body coordinate system O b -X b Y b Z b The direction conforms to the right-hand rule.

[0107] The second step is to calculate the maximum thrust and maximum torque of each degree of freedom of the ROV horizontal and vertical planes in theory. b -X b Y b Z b Position layout parameters, refer to the thrust equations of equations (1) and (2) to determine the horizontal plane vector layout matrix A and the vertical plane vector layout matrix B. And according to the rated thrust T of the horizontal and vertical thrusters h , T v And equations (5) and (6) respectively calculate the maximum longitudinal force T on the horizontal plane xmax, maximum lateral force T ymax and the maximum yaw moment T Nmax , the maximum lift force T on the vertical surface zmax , maximum heeling moment T Rmax , Maximum pitch moment T pmax .

[0108] The third step is to decouple the horizontal plane from the vertical plane and calculate the initial thrust or torque of the ROV. The thrust and torque of the ROV are divided into the horizontal plane and the vertical plane for decoupling, and the initial longitudinal thrust T of the horizontal plane is calculated according to formula (3) based on the output control amount of the thrust or torque of the horizontal plane by the ROV operating handle or controller. x1 , initial lateral thrust T y1 , initial yaw moment T N1 According to the output control quantity of the thrust or torque of the vertical plane by the ROV operating handle or controller, the initial thrust or initial torque T of the vertical plane is calculated according to formula (4): z1 , T R1 , T p1 .

[0109] The fourth step is to calculate the additional thrust and torque. Calculate the additional torque of the horizontal thrust on the vertical plane and the additional influence of the vertical plane torque on the horizontal thrust after decoupling. Specifically, the initial longitudinal thrust T of the horizontal plane is calculated according to formula (7): x1 Pitch moment applied to vertical surface Initial lateral thrust T on the horizontal plane y1 Heeling moment about the vertical surface Initial heeling moment T on the vertical plane R1 With the initial pitch moment T p1 Transverse thrust on the horizontal plane

[0110] The fifth step is to calculate the comprehensive thrust and torque on the horizontal and vertical planes. According to equations (8) and (9), the initial thrust / torque on the horizontal and vertical planes is subtracted from the corresponding additional torque to obtain the comprehensive thrust or torque to be distributed on the horizontal plane T x , T y , T N , the integrated thrust or moment T to be distributed on the vertical surface z , T R , T p .

[0111] Step 6: Thrust distribution. The integrated thrust or torque T to be distributed on the horizontal plane x , T y , T N The combined thrust or moment T to be distributed on the vertical surface z , T R , Tp The thrust distribution is performed according to equation (10) and equation (11) respectively, and the output thrusts T1, T2, T3, and T4 of the horizontal thrusters and the output thrusts T5, T6, T7, and T8 of the vertical thrusters are obtained.

[0112] According to another aspect of an embodiment of the present application, there is also provided an electronic device, including a processor and a memory, wherein the processor is used to implement the steps of the thrust distribution method of the underwater working robot when executing a computer program stored in the memory.

[0113] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0114] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0115] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0116] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0117] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A thrust distribution method for an underwater working robot, characterized in that: The steps include: Establishing a main body coordinate system of the underwater working robot, wherein the main body coordinate system of the underwater working robot includes a longitudinal axis, a transverse axis and a vertical axis, and the origin of the coordinate system is located at the center of gravity of the underwater working robot; According to the position layout parameters of the horizontal and vertical thrusters in the coordinate system of the underwater working robot, the vector layout matrices of the horizontal and vertical planes are determined respectively, and the theoretical maximum thrust and torque of each degree of freedom in each direction are calculated; The thrust and torque of the underwater working robot are divided into the horizontal plane and the vertical plane, and the initial thrust or torque of the horizontal plane and the vertical plane are calculated through the output control quantity of the controller; According to the influence of the decoupled thrust on the opposite surface, the additional moment of the horizontal thrust on the vertical surface and the additional thrust of the vertical surface moment on the horizontal surface are calculated respectively; Subtract the corresponding additional thrust or additional torque from the initial thrust or torque on the horizontal plane and the vertical plane, respectively, to obtain the comprehensive thrust or comprehensive torque to be distributed; According to the comprehensive thrust or comprehensive torque, the thrust distribution results of the horizontal thruster and the vertical thruster are calculated respectively.

2. The thrust distribution method of the underwater working robot according to claim 1, characterized in that: The horizontal plane vector arrangement matrix is ​​determined by the following thrust equation: The vertical plane vector arrangement matrix is ​​determined by the following thrust equation: In formula (1): x For along O b X b Longitudinal thrust of the shaft, τ y O b Y b Transverse thrust of the shaft, τ N For around O b Z b A is the yaw moment of the axis, A is the horizontal plane vector arrangement matrix, T1 is the output thrust of the 1# thruster, T2 is the output thrust of the 2# thruster, T3 is the output thrust of the 3# thruster, and T4 is the output thrust of the 4# thruster; A ij (i=1,2,3,4; j=1,2,3,4) are the elements of the established horizontal plane vector arrangement matrix; In formula (2): Z For along O b Z b Axis lifting thrust, τ R For around O b X b Heeling moment of the axis, τ p For around O b Y b The longitudinal moment of the axis, B is the vertical plane vector arrangement matrix, T5 is the output thrust of the 5# thruster, T6 is the output thrust of the 6# thruster, T7 is the output thrust of the 7# thruster, and T8 is the output thrust of the 8# thruster; B ij (i=1, 2, 3, 4; j=1, 2, 3, 4) are elements of the established vertical plane vector arrangement matrix.

3. The thrust distribution method of the underwater working robot according to claim 2, characterized in that: Methods for calculating the theoretical maximum thrust and moment for each degree of freedom include: According to the following relationship, the relationship between the thrust or torque and the control quantity of each degree of freedom in the horizontal and vertical planes is constructed respectively: In formula (3): T xmax , T ymax , T Nmax are the maximum longitudinal force, maximum lateral force and maximum yaw moment corresponding to single free motion, u xmax 、u ymax 、u Nmax are the control quantities corresponding to the maximum longitudinal thrust, maximum lateral thrust and maximum yaw moment, respectively, u x 、u y 、u N are the control quantities corresponding to the initial longitudinal thrust, initial lateral thrust and initial yaw moment output by the underwater robot operator or controller at the current moment, T x1 , T y1 , T N1 They are the initial longitudinal thrust, initial lateral thrust and initial yaw moment of the underwater working robot at the current moment; In formula (4): T zmax , T Rmax , T Pmax They are the maximum lifting force, maximum heeling moment and maximum pitching moment during single free motion; u zmax 、u Rmax 、u Pmax are the control quantities corresponding to the maximum lifting force, the maximum heeling moment and the maximum pitching moment respectively; u z 、u R 、u P are the control quantities corresponding to the initial lifting force, initial heel moment and initial pitch moment output by the underwater robot operator or controller at the current moment; T z1 , T R1 , T P1 They are the initial lifting force, initial heel moment and initial pitch moment of the underwater working robot at the current moment respectively; For formula (3), the maximum longitudinal force, maximum lateral force and maximum yaw moment on the horizontal plane are calculated according to the following formulas: In formula (5): T h A is the rated thrust of the horizontal thruster; 11 , A 21 , A 31 Arrange the three elements of the first column of the matrix for the established horizontal plane vectors respectively; For formula (4), the maximum lift force, maximum heel moment and maximum pitch moment on the vertical plane are calculated according to the following formulas: In formula (6): T v is the rated thrust of the vertical thruster, B 11 , B 21 , B 31 The three elements of the first column of the matrix are arranged for the established perpendicular plane vectors respectively.

4. The thrust distribution method of the underwater working robot according to claim 1, characterized in that: According to the influence of the decoupled thrust on the opposite surface, the method of calculating the additional moment of the horizontal thrust on the vertical surface and the additional thrust of the vertical surface moment on the horizontal surface includes: Determine the initial longitudinal thrust and initial lateral thrust in the horizontal plane; Determine the distance parameter between the horizontal plane thruster and the center of gravity of the underwater operation robot; The initial longitudinal thrust, initial lateral thrust and distance parameters are used to calculate the pitch moment and heel moment exerted on the vertical plane by the initial longitudinal thrust and initial lateral thrust on the horizontal plane. Determine the initial thrust of the vertical plane and its relative position parameters to the horizontal plane; Calculate the lateral thrust exerted on the horizontal plane by the initial heeling moment and the initial pitching moment on the vertical plane.

5. The thrust distribution method of the underwater working robot according to claim 4, characterized in that: The calculation formulas for the pitch moment, heel moment and lateral thrust are as follows: In formula (7): is the heeling moment; is the pitch moment; is the lateral thrust; T x1 is the initial longitudinal thrust; T y1 is the initial lateral thrust; T P1 is the initial pitch moment; T R1 is the initial heeling moment; z h x is the distance from the origin of the underwater robot's coordinate system to the axis of the horizontal propeller; v is the distance from the vertical thruster to the x-axis of the underwater robot's coordinate system; v is the distance from the vertical thruster to the y-axis of the underwater working robot's body coordinate system; β is the angle between the vertical thruster and the positive z-axis of the underwater working robot's body coordinate system.

6. The thrust distribution method of the underwater working robot according to claim 1, characterized in that: The calculation formula for the comprehensive thrust or torque to be distributed is as follows: In formula (8): T x1 is the initial longitudinal thrust; T x is the comprehensive longitudinal thrust; T y1 is the initial lateral thrust; is the initial heeling moment T on the vertical plane R1 With the initial pitch moment T P1 Transverse thrust applied to the horizontal plane; T y is the comprehensive lateral thrust; T N1 is the initial yaw moment, T N is the integrated yaw moment; In formula (9): T Z1 is the initial lifting force; T z is the comprehensive lifting force; T R1 is the initial heeling moment; is the initial thrust T on the horizontal plane y1 Heeling moment applied to the vertical surface; T R is the comprehensive heeling moment; T P1 is the initial pitch moment, is the pitch moment exerted by the initial thrust on the horizontal plane on the vertical plane, T P is the comprehensive pitch moment.

7. The thrust distribution method of the underwater working robot according to claim 3, characterized in that: The calculation method of the thrust distribution result of the horizontal plane thruster includes: The comprehensive longitudinal force, comprehensive lateral force and comprehensive yaw moment of the horizontal plane are decomposed respectively to obtain the thrust expression of each thruster on the horizontal plane: In formula (10): T x is the comprehensive longitudinal thrust; T y is the comprehensive lateral thrust; T N is the comprehensive yaw moment; A ij (i=1,2,3,4;j=1,2,3,4) are the elements of the established horizontal plane vector arrangement matrix, and T1, T2, T3, and T4 are the output thrusts of the four thrusters on the horizontal plane after thrust distribution.

8. The thrust distribution method of the underwater working robot according to claim 1, characterized in that: The calculation method of the thrust distribution result of the vertical thruster includes: The lift force, heel moment and pitch moment of the vertical plane are decomposed respectively to obtain the thrust expression of each thruster in the vertical plane: In formula (11): T z is the comprehensive longitudinal thrust, T R is the comprehensive lateral thrust, T P is the comprehensive yaw moment, B ij (i=1,2,3,4;j=1,2,3,4) are the elements of the established vertical plane vector arrangement matrix, and T5, T6, T7 and T8 are the output thrusts of the four thrusters in the vertical plane after thrust distribution.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the processor is used to implement the steps of the thrust distribution method for the underwater working robot as claimed in any one of claims 1 to 8 when executing the computer program stored in the memory.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the thrust distribution method for the underwater working robot described in any one of claims 1 to 8 are implemented.

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