RU2799176C1 - Method for position-force control of an autonomous uninhabited underwater vehicle with a multistage manipulator - Google Patents

Abstract

FIELD: robotics.

SUBSTANCE: invention can be used to create control systems for autonomous uninhabited underwater vehicles (AUVs) with multi-stage manipulators (MM). For position-force control of an autonomous uninhabited underwater vehicle with a multi-stage manipulator in the mode of its hovering and preliminary stabilization, before the start of force operations with the object, taking into account the linear displacements of the underwater vehicle in space, determined by the technical vision system, and its angular displacements, determined by on-board gyroscopic sensors, variable desired values and directions of force effects exerted by the working body of the manipulator are set, the base of which is fixed under the centre of magnitude of the underwater vehicle. The object at each point of the trajectory of the movement of the operating body of the manipulator is formed using a 3D model of this object, whereas the inputs of the corresponding propellers of the underwater vehicle are supplied with control signals that reduce its deviations from the initial position when the manipulator moves in a viscous medium.

EFFECT: consistently accurate automatic performance of various technological operations by the AUV manipulator, requiring precise force interaction of the operating body (OB) of the MM with underwater objects.

1 cl, 1 dwg

Description

The invention relates to robotics and can be used to create control systems for autonomous uninhabited underwater vehicles (AUVs) with multi-stage manipulators (MM).

A known method for controlling the movement of a multi-stage anthropomorphic AUV manipulator, which consists in applying control actions to the electric drives of the joints to bring the working body (RO) of the MM to a given position at a given speed for a given time, calculated in the form of algebraic and transcendental expressions based on simplified dynamic models of electric drives and dynamic model of the MM formulated on the basis of the kinematic model of the manipulator, built using the Denavit-Hartenberg approach, and the dynamic model of the MM to achieve its final state is transformed into a system of differential equations that determine the angles of rotation of the MM links around their longitudinal and transverse axes, the right parts of which contain only desired controls. (Balabanov A. N., Bezuglaya A. E., Shushlyapin E. A. Control of the underwater robot manipulator // Informatics and automation. - 2021. - T. 20. - No. 6. - P. 1307-1332).

The disadvantage of this method is that the control actions applied to the electric drives of the MM joints are formed on the basis of dynamic models of the MM and electric drives that do not take into account the actual force and moment effects on the underwater vehicle from the side of the work object, transmitted through the links and joints of the manipulator to the point fixing the MM to the base of the AUV. But these impacts occur immediately after the establishment of the power contact of the RO (tool) MM with the surface of the object of work during the performance of any power technological operation. As a result, these impacts lead to an uncontrolled displacement of the AUV in space, and as a result, to a violation of the specified technological operation.

A known method of position-force control of AUV with MM, which consists in the formation of the law of control of the position of the vehicle with a manipulator and the force exerted on the surface of the object of work, based on their mathematical model, as a single object, using the assessment of Coriolis and centrifugal forces and moments, hydrostatic and hydrodynamic forces and moments of resistance to the movement of AUV with MM, including viscous friction and attached masses of fluid, while the errors in the assessment of these forces and moments are compensated by using a controller with a variable structure. (Barbalata C., Dunnigan M. W., Petillot Y. Coupled and decoupled force/motion controllers for an underwater vehicle-manipulator system // Journal of Marine Science and Engineering. - 2018. - Vol. 6. - No. 3. - P. 96).

The disadvantage of this method is that when forming the law for controlling the position of the AUV with the MM, the dynamic characteristics of the electric drives in the joints of the MM are not taken into account, as well as the force and moment effects acting on the AUV with the MM from the side of the object of work, caused by the reaction of the support during the force effect of the RO of the manipulator on surface of the work object. Because of this, in the process of performing a technological operation by the manipulator, a periodic loss of contact between the tool fixed at the end of the manipulator and the surface of the object of work is possible, and, as a result, a violation of the technological process.

There is a known method for controlling the AUV in the mode of its hovering near or above the object of work during the operation of the MM installed on it, including the supply to the inputs of the engines of all degrees of mobility of the manipulator of signals determined by the desired program trajectory of its motion in space in the aquatic environment and formed on the basis of analytical relationships obtained after solving the inverse problem of kinematics for a specific kinematic scheme of the MM, and to the inputs of the corresponding AUV propulsors - signals that compensate for the force and moment effects on this vehicle from the MM, which arbitrarily moves in a viscous medium, and the control signals for the AUV propulsors along an open loop are formed in real time based on analytical expressions that determine the force and moment with which this manipulator acts on the AUV, taking into account all the effects of mutual influence between all degrees of mobility of the MM, as well as hydrostatic and hydrodynamic forces of resistance to its movement, including viscous friction and the attached masses of the surrounding fluid ( Filaretov V.F., Alekseev Yu.K., Lebedev A.V. Control systems for underwater robots. - M.: All year round. - 2001. - C.171-179; 223-227).

Its disadvantage is that the analytical expressions that determine the force and moment with which the MM acts on the underwater vehicle do not take into account the force effects exerted by the working body of the manipulator on the objects of work during the performance of technological operations. In addition, the open loop stabilization of the underwater vehicle in space does not allow for accurate compensation of all forces and moments acting on it from the side of the manipulator, causing its inevitable displacement from the initial specified spatial location.

There is also known a method of position-force control of an AUV with a four-stage manipulator in the mode of its hovering and preliminary stabilization before the start of power operations with the object of work, which are carried out in the future, taking into account the linear displacements of the underwater vehicle in space, determined by the technical vision system, and its angular displacements, determined by onboard gyroscopic sensors, which consists in setting variable desired values and directions of force effects exerted by the working body of the manipulator, the base of which is fixed under the center of magnitude of the underwater vehicle, on the object of work at each point of the trajectory of its working body, which is formed using a 3D model of this at the same time, control signals are applied to the inputs of the corresponding propellers of the underwater vehicle, which reduce its deviations from the initial position when the manipulator moves in a viscous medium, while the control system of the AUV with MM is built using observers only of the total values of external moments acting on the output shafts of the drives of all degrees of mobility of the MM, these values form control signals for the MM drives and create the desired force effects of the MM on the objects of work at the current point of the RO movement trajectory and additional control signals for the MM drives that ensure the movement of this RO along the specified trajectory, and signals are sent to the inputs of the corresponding AUV propellers controls that compensate for the dynamic effects on this vehicle from the MM, these signals are calculated according to a recurrent algorithm that determines the total value of the force and moment impact on the AUV when moving its MM in a viscous medium and with the force impact of the RO on the objects of work (Konoplin A.Yu., Krasavin N.A., Yurmanov A.P., Pyatavin P.A., Katsurin A.A. Position-Force Control System for Underwater Vehicles with Multilink Manipulators to Perform Contact Manipulation Operations // Underwater Research and Robotics. - 2022. - No. 4. - P. 40-52).

This method is closest to the claimed invention.

The main disadvantage of this method is that the creation of the desired force vector from the MM RO on the objects of work is carried out by simultaneously applying full control actions to all drives of all MM joints. As a result, this immediately creates a full vector of force on the AUV, equal to the desired vector of force on the object of work, but opposite to it in direction. Since, at the same time, the propellers of the AUV hovering over the object of work do not yet generate thrust at all to compensate for the full force vector that has already appeared on the AUV from the side of the MM, then, having received an instantaneous force and moment effect, this AUV immediately begins to shift under the action of these forces and moments, moving away from the object of work, that is, its stabilization over the object of work is immediately violated. As a result, the contact of the MM with the object of work and its force impact on this object disappear. Having received an impulse of force and moment, the AUV will continue to move away from the object.

Studies have shown that after some time the vision system will detect the departure of the AUV from the object of work, this information will be transmitted with a delay to its tracking system, and only after that its propellers, which have a large inertia, will start (from scratch) to unwind. As a result, the AUV will strongly deviate from its previous initial position, taking into account the continuously increasing deviation, which may already become irreversible. Simultaneously with the spinning of the screws, taking into account all the dynamic delays, the configuration of the MM will begin to change to restore the force contact with the object of work. Therefore, the AUV restoring its original position (under the action of its stabilization system) and the MM working tool will begin their simultaneous movement towards this object of work after some time. This will inevitably lead to the impact of the working tool on this object due to the inevitable inertia of the AUV. And all this described process of collisions, as studies of the proposed AUV and MM control system show, will constantly occur during the implementation of attempts to create force effects using MM on the object of work.

The second important drawback is the inability to create an arbitrary position-force control of the MM, which has only 4 degrees of mobility. This is not enough to set any spatial vector of force impact on objects. For this purpose, it is necessary to have six degrees of freedom. That is, the MM of the prototype, in principle, is not able to solve the problem of arbitrary force impact on the object of work.

The third disadvantage of the prototype is that when the RO MM moves along the trajectory to set the desired force on the object of work during this movement, additional control signals are supplied to the inputs of the manipulator drives, which are formed taking into account only this desired effort. But part of the indicated effort will certainly be spent on overcoming the dry sliding friction and the resistance of the material along the surface of the object. As a result, the magnitude and direction of the vector of this force will differ significantly from the desired ones, or the RO, in principle, will not move along the indicated trajectory.

And, finally, the fourth significant drawback of the prototype is that the observers used in it are used to estimate the values of only the total external moments acting on the output shafts of drives of all degrees of freedom of the MM, including the effects of mutual influence between all degrees of freedom of the manipulator, and hydrostatic forces, and hydrodynamic forces of resistance to the movement of links (including viscous friction, added masses and moments of inertia of the surrounding fluid), and possible force effects on the objects of work. At the same time, the determination of the components due to the force effects of the RO on the objects of work is carried out by subtracting from the total external moment on the output shaft of each MM drive the components of this external moment calculated using the recurrent algorithm, due to the hydrostatic and hydrodynamic forces of resistance to the movement of the links, as well as the effects of mutual influence between all degrees of mobility MM. But the inevitable presence of large errors in setting the estimated values of the added masses and the attached moments of inertia of the fluid to the MM links in the recurrent algorithm used, as shown by the research results, will necessarily lead to large errors in determining and setting the real values and directions of the force and moment action vectors, as well as to large errors in AUV stabilization at a given point in space. In this case, there will inevitably be loss of contacts between the objects of work and the working tools of the MM or periodic impacts of these tools on the specified objects of work, which can lead to breakage of the working tools or objects of work.

The remaining less significant disadvantages of the prototype will be presented and described in detail in the description and justification of each of the features of the distinctive part of the claims.

The objective of the claimed invention is to eliminate the above disadvantages, i.e. accurate automatic execution of AUV with MM required power technological operations over the entire surface of work objects in an aqueous (viscous) medium.

The technical result of the invention consists in the invariably accurate automatic performance by the AUV manipulator of various technological operations that require precise force interaction of the MM RO with underwater objects, when it is necessary to ensure the accurate movement of the RO along any spatial trajectories in the MM working area with the simultaneous creation of a force impact specified in magnitude and direction with RO side to these objects without possible loss of contacts with these objects.

In the claimed invention, this is proposed to be achieved by accurate stabilization of the AUV over an underwater object using a technical vision system and AUV orientation sensors in space by creating, after contact of the MM RO with the surface of the object, in real time the AUV propulsion devices coordinated in time and thrust, which, taking into account the current configuration of the MM will continuously and steadily ensure the creation of the required magnitude and direction of force and moment effects on the underwater object, as well as the precise program movement of the MM in space, which is formed due to signals supplied to the inputs of the corresponding MM drives, which simultaneously take into account external force and torque impacts caused by the interaction of this MM with the objects of work and its movement in a viscous medium.

The problem is solved by the fact that the method of position-force control of an autonomous uninhabited underwater vehicle with a manipulator in the mode of its hovering and preliminary stabilization before the start of power operations with the object of work, which are carried out in the future, taking into account the linear displacements of the underwater vehicle in space, determined by the vision system , and its angular displacements, determined by onboard gyroscopic sensors, which consists in setting variable desired values and directions of force effects exerted by the working body of the manipulator, the base of which is fixed under the center of magnitude of the underwater vehicle, on the object of work at each point of the trajectory of its working body, which is formed using a 3D model of this object of work. At the same time, control signals are fed to the inputs of the corresponding propellers of the underwater vehicle, which reduce its deviations from the initial position when the manipulator moves in a viscous medium. The outer body of the underwater vehicle is made symmetrical about its main vertical axis in the form of an ellipsoid flattened along this axis, and the projection of this body on a plane passing through the other two main axes of symmetry has the shape of a circle. Six propellers of the underwater vehicle are fixed in pairs on its main axes of symmetry at the same distance relative to its center of magnitude so that the axes of their rods in pairs are always perpendicular to the axes of the rods of the remaining pairs of propulsors and provide the underwater vehicle with six degrees of freedom. The kinematic scheme of the manipulator of the underwater vehicle also has six degrees of freedom, three of which are portable and three are orienting. It enables its working body to provide any spatial orientation of the vectors of force and moment impact on the objects of work, before the start of any working operations during the test movements of the manipulator with the body of the underwater vehicle fixed in space, using the Kalman filter, the masses and moments of inertia of the surrounding fluid are identified, attached to the two main links of the portable degrees of freedom of the manipulator, after the approach of the underwater vehicle and its stabilization near the object of work, by identifying the current spatial location of the underwater vehicle and the starting point of the formed trajectory using the technical vision system and three markers, and also knowing the initial location of the manipulator, after solving the inverse problem of kinematics determine the laws of change in time of all its generalized coordinates, after which the working body of the manipulator is transferred from the initial position to the starting point of the trajectory, synchronously, as a function of time, giving signals corresponding to the indicated laws of change in generalized coordinates, to the inputs of servo drives of all degrees of freedom of the manipulator, providing a smooth transfer of its working body from the initial position to contact with the object at the starting point of the formed trajectory. At the same time, according to the well-known recurrent algorithm for solving the inverse problem of dynamics, taking into account the previously identified added masses and moments of inertia of the liquid, the force and moment effects on the underwater vehicle from this manipulator moving in the aquatic environment are calculated in real time, which are compensated by a smooth change in the thrust of its corresponding propulsors , stabilizing the underwater vehicle at a given point in space, after detecting by a typical tactile sensor the contact of the working body of the manipulator with the object of work, using recurrence relations, taking into account the current configuration of the manipulator, determine the laws of change in time of the desired thrusts of the corresponding propulsion of the underwater vehicle and the desired external moments in all joints of the manipulator , with the help of which the desired values of the input signals to the corresponding propulsion of the underwater vehicle and the manipulator drives are also formed as a function of time, the synchronous implementation of these signals ensures a smooth increase from zero to the final value of the program force and moment effects from the working body on the object of work at the beginning of the trajectory . At the same time, the original current configuration of the manipulator is kept unchanged, while at the same time providing more accurate stabilization of the position and orientation of the underwater vehicle in the absolute coordinate system due to the compensation of smoothly increasing force and moment effects from the manipulator by its propulsors, the actual inaccuracies of the specified software compensation are eliminated using a typical stabilization system , which uses information received from the vision system and negative feedbacks over all degrees of freedom of the underwater vehicle, using this system, create additional control signals for the corresponding propulsion devices that keep the underwater vehicle at its initial point in space with the initial orientation, after the formation of the initial force vector impacts from the working body of the manipulator on the object of work form a new value and direction of this vector, which already takes into account additional components of dry friction and resistance to movement of the working body at the beginning of the constructed trajectory, this vector is also formed using the propulsion of the underwater vehicle by supplying smoothly and synchronously changing input signals to the corresponding propellers and drives of the manipulator, after constructing the mentioned vector, depending on the program being executed, the speed of movement of the working body of the manipulator along the previously formed trajectory is set and this movement is started by applying to the inputs of the position-force control systems of the manipulator drives the corresponding signals, which include software and the actual values of the generalized coordinates of the manipulator, their velocities and accelerations, as well as the program and actual values of external moments, due only to the force interaction of the working body of the manipulator with the surface of the object of work, and the actual values of these external moments are determined using diagnostic observers of the total values of the generalized external moments, from which the components of mutual influences with real values of the masses and moments of inertia of the links of the manipulator, moments from the action of hydrostatic forces, moments of viscous friction, as well as moments due to the presence of already identified added masses and moments of inertia of the liquid are subtracted. During the movement of the manipulator along the formed trajectory, the force and moment effects that the manipulator moving in the aquatic environment exerts on the underwater vehicle at the point of its attachment to the latter are determined, these effects are calculated using a recurrent algorithm using the identified values of the attached masses and moments of fluid inertia, friction arising from the movement of all links of the manipulator in the aquatic environment, moments of mutual influence between all degrees of freedom of the manipulator, as well as forces and moments acting from the side of the object of work on the working body of the manipulator. All these impacts on the underwater vehicle are synchronously and smoothly compensated by its propellers. At the same time, due to inaccuracies in determining some parameters of force effects, the said system for stabilizing the position and orientation of the underwater vehicle in the absolute coordinate system is additionally used, with the help of which additional signals for controlling its propulsion are formed.

The compared analysis of the features of the proposed method with the features of analogues and the prototype testifies to the compliance of this method with the criterion of "novelty".

In this case, the distinctive features of the claims solve the following functional tasks.

The sign "... the outer body of the underwater vehicle is made symmetrical about its main vertical axis in the form of an ellipsoid flattened along this axis, and the projection of this body on a plane passing through the other two main axes of symmetry has the shape of a circle, ...", in contrast to that used in prototype of the shape of the body of the underwater vehicle, allows for additional passive stabilization of the underwater vehicle with a manipulator, which is an unstable inverted pendulum, along its main vertical axis due to its special shape of an ellipsoid flattened along this axis.

The sign "... and six propellers of the underwater vehicle are fixed in pairs on its main axes of symmetry at the same distance relative to its center of magnitude so that the axes of their rods in pairs are always perpendicular to the axes of the rods of the remaining pairs of propulsors and provide the underwater vehicle with six degrees of freedom, ..." allows you to provide a simple and reliable controllability of the apparatus in all six of its degrees of freedom due to the proposed arrangement of its propellers symmetrically with respect to its center of magnitude. With the propeller configuration used in the prototype, where the main propellers are located not on one of the main axes of symmetry of the underwater vehicle body, but are shifted to its rear part, in the process of turning along the angle of the apparatus’s heading, linear displacements of its geometric center inevitably occur, which must be compensated for by other pairs of propellers . In contrast to the above configuration, due to the arrangement of all propulsion devices of the underwater vehicle symmetrically about its center of magnitude, the new solution made it possible to ensure independent control of the vehicle in all six degrees of freedom.

The sign "... the kinematic scheme of the underwater vehicle manipulator also has six degrees of freedom, three of which are portable and three are orienting, it enables its working body to provide any spatial orientation of the force and moment effect vectors on the objects of work, ...", in contrast to the one used in the prototype of a four-degree manipulator, allows you to provide any spatial orientation of the vectors of force and moment impact of the working body of the manipulator on the objects of work within its working area through the use of a kinematic scheme with three portable and three orienting degrees of freedom.

The sign “... before the start of any work operations during the test movements of the manipulator with the body of the underwater vehicle fixed in space, using the Kalman filter, the masses and moments of inertia of the surrounding fluid are identified, attached to the two main links of the portable degrees of freedom of the manipulator, ...” allows you to accurately determine the values attached to the main links of the portable degrees of mobility of the mass manipulator and the moments of inertia of the surrounding fluid, taking into account the direction of the fluid flows incident on these links. In contrast to the use in the prototype of some averaged values of the attached masses and moments of inertia of the fluid, the new solution proposes and uses the exact identification of these values. The use of these values allows, with a much smaller error, to determine the force and moment acting on the hull of the underwater vehicle from the side of the manipulator moving in a viscous medium. In addition, the same values are included in the total moments developed by the corresponding manipulator drives. In the proposed solution, in contrast to the prototype, it was possible to isolate those parts of the moment as a function of time that are necessary to create the required movement in a specific degree of mobility of the manipulator and at the same time the required moment, which, taking into account the moments formed in its other degrees of freedom, provides the required force effect of the working body manipulator on the object of work. Without this, using only already known methods, it is impossible to implement simultaneous high-quality positional-force control of each degree of manipulator mobility, and as a result, the required precise movement of the manipulator working body as a whole along a given trajectory with a given force effect on the object.

Sign “... after the approach of the underwater vehicle and its stabilization near the object of work, having identified the current spatial location of the underwater vehicle and the starting point of the formed trajectory using the technical vision system and three markers, and also knowing the initial location of the manipulator, after solving the inverse problem of kinematics, determine the laws of change in time of all its generalized coordinates, after which the working body of the manipulator is transferred from the initial position to the starting point of the trajectory, synchronously as a function of time, giving signals corresponding to the indicated laws of change in generalized coordinates, to the inputs of servo drives of all degrees of freedom of the manipulator, ensuring a smooth transfer of its working body from from the initial position to contact with the object at the initial point of the formed trajectory, at the same time, according to the well-known recurrent algorithm for solving the inverse problem of dynamics, taking into account the previously identified added masses and moments of inertia of the liquid, the force and moment effects on the underwater vehicle from this moving vehicle are calculated in real time the aquatic environment of the manipulator, which are compensated by a smooth change in the rods of its respective propellers, stabilizing the underwater vehicle at a given point in space, ... "provides an accurate transfer of the working body of the manipulator from its current position to its original position at the beginning of the trajectory formed on the surface of the work object until the working body touches this object . During this transfer, with the help of the propulsion rods of the underwater vehicle, its position and orientation are smoothly stabilized by compensating for force and moment effects transmitted to its body from the side of the moving manipulator, which are due to viscous friction moments, mutual influences between the manipulator links moving in a viscous medium, and also the presence of precisely defined added masses and moments of inertia of the surrounding fluid.

The sign "... after a typical tactile sensor detects contact of the working body of the manipulator with the object of work, ..." allows you to identify the fact of the appearance of contact between the working body of the manipulator and the object of work when this working body is transferred to the starting point of the trajectory. As a result, it is possible to exclude a possible gap between the surface of the object of work and the working body of the manipulator, and, consequently, the possible collision of this body with the object at the stage of the appearance of a force impact on this object.

Feature “... using recurrent relations, taking into account the current configuration of the manipulator, the laws of change in time of the desired thrusts of the corresponding propulsors of the underwater vehicle and the desired external moments in all joints of the manipulator are determined, with the help of which the desired values of the input signals to the corresponding propulsors of the underwater vehicle are also formed as a function of time and manipulator drives, the synchronous implementation of these signals ensures a smooth increase from zero to the final value of the program force and torque effects from the working body on the work object at the beginning of the trajectory, while maintaining the original current configuration of the manipulator unchanged, while providing more accurate stabilization of the position and orientation of the underwater apparatus in the absolute coordinate system due to the compensation by its propulsors of smoothly increasing force and moment effects from the side of the manipulator, the actual inaccuracies of the specified software compensation are eliminated using a typical stabilization system using information received from the vision system and negative feedbacks for all degrees of freedom underwater vehicle, using this system, create additional control signals for the corresponding propulsion devices that keep the underwater vehicle at its initial point in space with the initial orientation, ... "allows for a smooth increase in force and moment effects on the work object from zero to a given value due to the formation of the main vector and the main moment of the thrusts by all propulsion units of the underwater vehicle, while maintaining the initial configuration of the manipulator, as well as the initial position and orientation of the said vehicle in space. This is a fundamental difference from the prototype, in which the formation of vectors of force and torque effects on the object of work is carried out by applying appropriate control signals to the manipulator drives, without providing a gradual and smooth formation of these vectors. But with the simultaneous supply of final stepped input signals at once to the drives of all joints of the manipulator without the preliminary required spin-up of the corresponding propulsors, the underwater vehicle, taking into account the real dynamic delay in these propulsors, will immediately be thrown away from its original position, in many cases losing contact between the working tool and the object of work. .

Sign "... after the formation of the initial vector of the force impact from the side of the working body of the manipulator on the object of work, a new value and direction of this vector is formed, which already takes into account additional components of dry friction and resistance to movement of the working body at the beginning of the constructed trajectory, this vector is also formed with the help of underwater propellers of the device by applying smoothly and synchronously changing input signals to the corresponding propulsors and drives of the manipulator, after constructing the mentioned vector, depending on the program being executed, the speed of movement of the working body of the manipulator along the previously formed trajectory is set and this movement begins, ... "allows for the movement of the working body of the manipulator along the formed trajectories with the required force effect on the surface of the work object, depending on the technological operation, taking into account the force of dry friction and other resistance to the movement of the working body along the surface to be treated. In contrast to the method used in the prototype of setting the desired force impact on the object of work in the process of movement of the working body of the manipulator along the formed trajectory, the forces of dry friction and other resistance to the movement of this body are taken into account when forming the thrusts of the propulsors of the underwater vehicle.

Sign "... by supplying to the inputs of the position-force control systems of the manipulator drives the corresponding signals, which include program and actual values of the generalized coordinates of the manipulator, their speeds and accelerations, as well as program and actual values of external moments, due only to the force interaction of the working body of the manipulator with the surface of the object of work, and the actual values of these external moments are determined using diagnostic observers of the total values of generalized external moments, from which the components of mutual influences are subtracted with the real values of the masses and moments of inertia of the manipulator links, the moments from the action of hydrostatic forces, the moments of viscous friction, as well as the moments, due to the presence of already identified added masses and moments of inertia of the fluid, ... "allows for the precise movement of the working body of the manipulator along the formed trajectory with the simultaneous creation of accurate force and moment effects on the surface of the object of work. Unlike the prototype, when forming feedbacks of position-force control systems, the new solution uses the identified actual values of the external moments of the manipulator drives, due to the impact of the working body on the object of work. Without this, it is simply impossible to implement high-quality positional-force control of each degree of manipulator mobility. To calculate these actual values, the proposed solution uses the total values of generalized external moments determined with the help of diagnostic observers, from which the components of the mutual influences of the degrees of freedom of the manipulator on each other, the moments from the action of hydrostatic forces, the moments of viscous friction, as well as the moments due to the presence of precisely identified current values of the added masses and moments of inertia of the fluid.

Sign “... during the movement of the manipulator along the formed trajectory, the force and moment effects that the manipulator moving in the aquatic environment exerts on the underwater vehicle at the point of its attachment to the latter are determined, these effects are calculated using a recurrent algorithm using the identified values of the attached masses and moments of fluid inertia , moments of viscous friction arising from the movement of all parts of the manipulator in the aquatic environment, moments of mutual influence between all degrees of freedom of the manipulator, as well as forces and moments acting from the side of the object of work on the working body of the manipulator, all these effects on the underwater vehicle synchronously and smoothly compensate for it propellers, while due to inaccuracies in determining some parameters of force effects, the above-mentioned system for stabilizing the position and orientation of the underwater vehicle in the absolute coordinate system is additionally used, with the help of which additional control signals for its propulsors are formed ... "allows for accurate stabilization of the underwater vehicle in the process of performing power technological operations. Unlike the underwater vehicle stabilization method used in the prototype only with the help of its tracking systems, the proposed new solution due to special identification and taking into account the current values of the attached masses and moments of inertia of the fluid, as well as accurately calculated viscous friction and moments due to mutual influences between the degrees of mobility of the moving in the viscous medium of the manipulator, allows you to more accurately determine the magnitude of the force and torque effects on the body of the underwater vehicle from the side of the moving manipulator and compensate for them by smoothly changing thrusts of the propellers of the specified apparatus, applying extremely accurately calculated program signals to their inputs. And only nevertheless appearing, but small displacements of the underwater vehicle from its initial position are compensated by the previously mentioned typical stabilization systems, using information coming with a delay from its vision systems and gyroscopic sensors.

2 – шестистепенной ММ с рабочим органом (РО) 3, закрепленный в нижней части АНПА на его вертикальной центральной оси симметрии; 4 – система технического зрения (СТЗ) с двумя вращательными взаимно перпендикулярными степенями подвижности, закрепленная в нижней части корпуса АНПА в его вертикальной плоскости симметрии; 5 – объект работ (ОР); 6 – очередная траектория движения конца РО, оказывающего силовое воздействие на ОР в процессе этого движения; A, B – начальная и конечная точки траектории 6; M₁, M₂ и M₃ – неподвижные маркеры, находящиеся в поле зрения СТЗ в процессе движения ММ; OXYZ – абсолютная система координат (АСК) (ее ось Z направлена вертикально вниз); C – геометрический центр корпуса АНПА 1; D – точка крепления ММ 2 к корпусу АНПА 1;

– система координат (СК), связанная с корпусом АНПА (оси СК совпадают с главными центральными осями симметрии АНПА);

– СК, связанная со светочувствительной матрицей СТЗ АНПА (ее ось

направлена вдоль оптической оси СТЗ); τ,

– соответственно, главный вектор и главный момент тяг, создаваемых всеми движителями, действующие в центре симметрии АНПА;

– соответственно, главный вектор и главный момент сил, действующих на АНПА со стороны ММ в точке

– соответственно, главный вектор и главный момент сил, действующих в точке D при формировании движителями АНПА векторов

– соответственно, векторы силы и момента, действующие со стороны РО ММ на ОР.The claimed invention is illustrated by a drawing (see Fig. 1), on which the following designations are introduced: 1 - AUV hull controlled in six degrees of freedom by six propulsion units installed in its hull and having pairs of parallel rods Pi,

2 - six-degree MM with a working body (RO) 3, fixed in the lower part of the AUV on its vertical central axis of symmetry; 4 – vision system (VS) with two rotational mutually perpendicular degrees of freedom, fixed in the lower part of the AUV body in its vertical plane of symmetry; 5 - object of work (OP); 6 - the next trajectory of the movement of the end of the RO, which has a force effect on the OR in the process of this movement; A, B are the start and end points of trajectory 6; M ₁ , M ₂ and M ₃ are fixed markers that are in the field of view of the VS during the MM movement; OXYZ is the absolute coordinate system (ACS) (its Z-axis is directed vertically down); C is the geometric center of the AUV 1 hull; D - point of attachment of MM 2 to the body of AUV 1;

– coordinate system (SC) associated with the AUV body (SC axes coincide with the main central symmetry axes of the AUV);

– SC associated with the photosensitive matrix of the STZ AUV (its axis

directed along the optical axis of the STZ); τ,

- respectively, the main vector and the main moment of the thrusts created by all propulsors, acting in the center of symmetry of the AUV;

- respectively, the main vector and the main moment of forces acting on the AUV from the MM at the point

- respectively, the main vector and the main moment of forces acting at point D during the formation of vectors by the propellers of the AUV

- respectively, the force and moment vectors acting from the MM RO on the OR.

симметрично располагают по паре движителей, силы тяги которых направлены перпендикулярно соответствующим осям этой СК. Для обеспечения большей устойчивости АНПА точка крепления основания ММ 2 располагается на оси

под центром величины C его корпуса. Внешний корпус АНПА 1 выполняют симметричным относительно его главной вертикальной оси в виде эллипсоида, сплющенного вдоль этой оси, причем проекция этого корпуса на плоскость, проходящую через две другие главные оси симметрии, имеет форму круга. Кинематическая схема ММ 2 также имеет шесть степеней свободы (подвижности), три из которых – переносные и три – ориентирующие, давая возможность его РО 3 обеспечивать любую пространственную ориентацию векторов силового

и моментного

воздействий на ОР 5 в его рабочей зоне.The claimed method is implemented as follows. To ensure accurate performance of contact (power) operations under water, the AUV 1 has a propulsion arrangement that ensures its control over all six degrees of freedom at once. This arrangement is shown in Fig. 1, where on each axis of the SC

symmetrically placed on a pair of propellers, the traction forces of which are directed perpendicular to the corresponding axes of this SC. To ensure greater stability of the AUV, the attachment point of the MM 2 base is located on the axis

under the center of magnitude C of its hull. The outer body of the AUV 1 is made symmetrical about its main vertical axis in the form of an ellipsoid flattened along this axis, and the projection of this body on a plane passing through the other two main axes of symmetry has the shape of a circle. The MM 2 kinematic scheme also has six degrees of freedom (mobility), three of which are portable and three are orienting, enabling its RO 3 to provide any spatial orientation of the force vectors.

and instant

impacts on OP 5 in its working area.

Before the start of any contact (force) operations, the masses attached to the moving parts of the manipulator and the moments of inertia of the surrounding fluid are identified, but since the links of the orienting degrees of freedom of the MM always have small lengths, these attached masses and the moments of inertia of the fluid are determined only in its two main moving parts. MM 2 links. To do this, the AUV 1 body is fixedly fixed in the aquatic environment, and for its MM 2 motion is set along test trajectories, and these trajectories are formed so that all generalized coordinates of the portable degrees of mobility of MM 2 change simultaneously. When moving along the specified trajectories on the output shafts of the electric drives of each of the three portable degrees of freedom of the MM 2 are affected by generalized external moments due only to the effects of mutual influence between the two main links of the MM, as well as hydrostatic and hydrodynamic forces of resistance to its movement, including viscous friction, as well as the attached masses and moments of inertia of the surrounding fluid. That is, in these generalized external moments there are no components due to the force interaction of RO 3 MM 2 with OR 5.

The values of generalized external moments, as well as the speed and acceleration of changes in the generalized coordinates of MM 2 are determined in real time using diagnostic observers (Zhirabok A.N., Zuev A.V., Filaretov V.F., Shumsky A.E. Identification of defects in nonlinear systems based on sliding observers with weakened existence conditions // Izvestiya RAN. Theory and control systems. - 2022. - No. 3. - P. 21-30), taking into account the dynamic features of actuators. From the obtained generalized moments, the components of the mutual influences of the portable degrees of freedom on each other are subtracted, taking into account the masses and moments of inertia of only two indicated MM links, calculated analytically (Shahinpur M. Course of robotics. - M .: Mir. - 1990. - C. 312-333) , as well as moments from the action of hydrostatic forces (they are considered standard) and viscous friction forces. To calculate the moments of viscous friction, each of the two indicated links MM 2 is divided into a finite number of elementary parts of the same length and calculated by a known method (Filaretov V.F., Konoplin A.Yu. Automatic stabilization system for an underwater vehicle in hover mode with a multi-link manipulator operating. Part 1 // Mechatronics, automation, control. - 2014. - No. 6. - P. 53-56) the viscous friction force acting on each of these parts, taking into account the value of the Reynolds number for all moving parts of the link. The remaining part of the generalized moment in each degree of mobility of the MM, due only to the presence of unknown added masses and moments of inertia of the fluid, is presented in an analytical form and converted into a linear regression form by grouping unknown parameters with respect to known components. In this case, the added fluid masses are specified in a known way (Fossen T.I. Guidance and control of oceanic vehicles. - John Willei and Sons. - 1994. - P. 117-121) in a matrix form that takes into account the change in the value of the attached mass of the link depending on its orientation to oncoming fluid flow. Further, the unknown values of the added masses and moments of inertia of the fluid are accurately determined using the Kalman filter (Ikonen E. Advanced process identification and control / E. Ikonen, K. Najim. - Marsel Dekker Inc. - 2002. - P. 37-45), using information about the change in the generalized coordinates of MM 2 and their derivatives at each moment in time of the movement of its RO 3 along test trajectories.

(в качестве маркеров можно использовать особенности конструкции ОР или рельефы дна) на ОР 5 или на дне вблизи него позволяет обеспечить с помощью СТЗ 4 привязку АНПА (его точку C) к некоторой исходной точке трехмерного водного пространства над ОР 5. Then, using STZ 4, before the start of work operations, the AUV 1 is automatically moved in the aquatic environment so that the parts of interest OR 5 are in the working area of MM 2. Mutual arrangement of at least three arbitrary markers

(you can use the design features of the OP or the bottom topography as markers) on the OP 5 or on the bottom near it, it allows using the STZ 4 to bind the AUV (its point C) to some starting point of the three-dimensional water space above the OP 5.

After stabilization of the point C of the AUV 1 in the underwater space with the help of the STZ 4, a 3D model of the OP 5 is formed, for which, as a function of time, the desired trajectories of the RO 3 movement are built, which are presented in the memory of the control controller as a set of sequentially located points or in the form of an analytical description by splines, with its required orientation in the ASC, as well as with the direction and magnitude of the force impact (or moment) on the OR 5 at each point of these trajectories, which should be located in the working area of the MM 2 and in the field of view of the STZ 4 with a movable optical axis. Then, for each point of the trajectories 6, also as a function of time, solving typical inverse kinematic problems (KK) on the control controller (Fu K., Gonzales R. C., Lee C. S. G. Robotics: control, sensing, vision and intelligence // McGraw Hill. - 1987. - P. 53-75) for the well-known design of MM 2, determine and store in the memory of the control controller the desired laws of change in time of all generalized coordinates of this MM 2 for each trajectory of its RO 3.

после решения ОЗК для этого ММ, определяют законы изменения во времени всех его обобщенных координат при переводе РО 3 ММ 2 из его исходного положения в точку A траектории 6 и затем подают уже определенные законы изменения всех обобщенных координат на входы приводов соответствующих степеней подвижности ММ 2 в функции времени, обеспечивая перевод его РО 3 из исходного положения до касания ОР 5 в точке A. Во время этого перевода, непрерывно в реальном масштабе зрения решая обратную задачу динамики (ОЗД) для ММ 2 по известному рекуррентному алгоритму (Филаретов В.Ф., Коноплин А.Ю. Система автоматической стабилизации подводного аппарата в режиме зависания при работающем многозвенном манипуляторе. Часть 1 // Мехатроника, автоматизация, управление. – 2014. – № 6. – С. 53-56) с учетом ранее идентифицированных присоединенных масс и моментов инерции жидкости, определяют плавно изменяющиеся силовое

и моментное

воздействия на АНПА 1 со стороны перемещающегося в вязкой среде ММ 2. Эти воздействия автоматически компенсируют плавными изменениями тяг соответствующих движителей

АНПА 1, которые формируют, подавая соответствующие рассчитываемые сигналы на их входы. Оставшиеся неточности отработки движителями смещений точки C АНПА 1 от ее исходной позиции в пространстве и от горизонтального расположения осей

обусловленных воздействиями

со стороны движущегося ММ 2, определяют и дополнительно компенсируют с помощью имеющихся следящих систем стабилизации АНПА 1 при наличии дополнительной информации, получаемой от его бортовой навигационной системы и от СТЗ 4, которая фиксирует смещения точки C АНПА 1 относительно маркеров

Further, knowing the current location of point C and point A (using the readings of STZ 4) in the ASC, as well as the initial location of MM 2 in the associated SC

after solving the OZK for this MM, determine the laws of change in time of all its generalized coordinates when transferring RO 3 MM 2 from its initial position to point A of the trajectory 6 and then apply the already defined laws of change of all generalized coordinates to the inputs of the drives of the corresponding degrees of freedom of MM 2 in functions of time, ensuring the transfer of its RO 3 from its original position to touching OP 5 at point A. During this transfer, continuously in the real scale of vision, solving the inverse problem of dynamics (OZD) for MM 2 according to the well-known recurrent algorithm (Filaretov V.F., Konoplin A.Yu. Automatic stabilization system of an underwater vehicle in the hovering mode with a working multi-link manipulator. Part 1 // Mechatronics, automation, control. - 2014. - No. 6. - P. 53-56) taking into account previously identified attached masses and moments fluid inertia, determine the smoothly changing force

and instant

impacts on AUV 1 from the side of MM 2 moving in a viscous medium. These impacts are automatically compensated by smooth changes in the thrust of the corresponding propulsors

AUV 1, which are formed by applying the appropriate calculated signals to their inputs. The remaining inaccuracies in working out by the movers of the displacement of point C of the AUV 1 from its initial position in space and from the horizontal position of the axes

due to impacts

from the side of the moving MM 2, are determined and additionally compensated using the available AUV 1 stabilization tracking systems in the presence of additional information received from its onboard navigation system and from STZ 4, which fixes the offset of the AUV 1 point C relative to the markers

и (или) момент

со стороны РО 3 на ОР 5.The fact of detecting the contact of RO 3 with OP 5 at point A is provided by standard tactile sensors installed at the attachment point of RO 3 to the last link of MM 2, or by other known means. After identifying this contact and finally restoring the initial position of the point C of the AUV in the space above OP 5 with the help of AUV tracking stabilization systems, using known recurrence relations (Filaretov V.F., Zuev A.V., Gubankov A.S. Control of manipulators when performing various technological operations. - M.: Nauka, 2018. - pp. 99-102), taking into account the current configuration of the MM, the desired values of external moments in all MM joints and the desired thrust of the AUV propulsors are determined, which together create at point A the initial desired and possibly variable in magnitude and direction force

and/or moment

from RO 3 to OP 5.

в точке D –

а в точке A при текущей конфигурации ММ 2 – требуемые исходные значения

и

. Величина указанного временного интервала зависит от величин

,

и динамических свойств движителей АНПА. Одновременно с подачей сигналов на движители АНПА в том же временном интервале путем типового решения ОЗД на вход каждого следящего привода соответствующей степени подвижности ММ 2 с учетом непрерывно вычисляемых для текущего момента времени

,

также равномерно во времени подают соответствующие программные сигналы, которые, обеспечивая равномерные нарастания внешних моментных воздействий на выходах всех приводов, создают равномерное реальное нарастание силовых и моментных воздействий

,

на ОР 5, не позволяя при этом ММ 2 изменять свою исходную (в момент первого контакта его РО 3 с ОР 5) конфигурацию. При этом сам АНПА 1, опирающийся на манипулятор сверху и представляющий собой неустойчивый перевернутый маятник, сохраняет свое устойчивое положение в пространстве (стабильные положение точки C и ориентацию осей

даже при некоторых погрешностях в определении создаваемых силовых и моментных воздействий. Это обеспечивают путем создания незначительных дополнительных тяг движителей АНПА, которые формируют следящими системами его стабилизации, устраняя появление со временем даже малых линейных смещений точки C и ориентаций осей

от их исходных позиций в АСК. Эти малые смещения также определяют с помощью СТЗ 4 и трех неподвижных маркеров М₁-М₃.Then, program signals are sent to the inputs of the corresponding AUV propulsors in a coordinated manner, changing smoothly and evenly in a given time interval from zero to their calculated values, which at point C form

at point D -

and at point A with the current configuration of MM 2 - the required initial values

And

. The value of the specified time interval depends on the values

,

and dynamic properties of AUV propellers. Simultaneously with the supply of signals to the AUV propulsion in the same time interval by a typical solution of the OZD to the input of each servo drive of the corresponding degree of mobility MM 2, taking into account continuously calculated for the current moment of time

,

the corresponding program signals are also given uniformly in time, which, providing a uniform increase in external torque effects at the outputs of all drives, create a uniform real increase in force and torque effects

,

on OP 5, while not allowing MM 2 to change its original (at the time of the first contact of its PO 3 with OP 5) configuration. At the same time, the AUV 1 itself, which rests on the manipulator from above and is an unstable inverted pendulum, retains its stable position in space (the stable position of point C and the orientation of the axes

even with some errors in determining the generated force and moment effects. This is ensured by creating insignificant additional thrusts of the AUV propulsors, which are formed by tracking systems for its stabilization, eliminating the appearance over time of even small linear displacements of point C and axis orientations.

from their original positions in the ACK. These small displacements are also determined using STZ 4 and three fixed markers M ₁ -M ₃ .

If RO 3 performs, for example, only taking samples of the bottom soil, then upon reaching the F _T value necessary to enter the RO into the soil, the process of deepening it with the help of MM 2 begins, which, when the AUV 1 is stationary, is provided by the control system of this MM. With the help of this system, when forming the appropriate control laws for all drives of all degrees of mobility of MM 2, continuously using the solutions of the OZK and OZD of the MM, taking into account all the forces of mutual influence between all degrees of its mobility on each other, the forces of viscous friction, as well as the attached masses and moments of inertia of the fluid , as well as the current readings of the STZ 4, provide the required linear movement of the RO 3 MM 2 deep into the bottom at a given angle to it, and then the sampler is removed from the soil in the reverse order.

If RO 3 needs to be displaced with given F _T and M _T (possibly variable), along the previously formed trajectory 6 along the surface of OP 5 from point A to point B, then vectors of dry friction forces are added to the initial force vector F _T and force impact on the object along the trajectory 6. As a result, new vectors of forces and moments (F _T and M _T ) are formed. These new vectors begin to be used when transferring RO 3 from the starting point A to the next point on the trajectory 6. At the same time, to obtain new vectors F _T and M _T with the current configuration of MM 2, new vectors F _D2 and M _D2 are calculated using the previously indicated recurrence relations, and then the thrust of all six propellers of the AUV 1. At the same time, new values of program signals are also generated, applied to all drives MM 2 to create external moments on the drives of all its degrees of freedom, corresponding to the values of the obtained new values F _T , M _T .

Before the start of the working movement MM 2, depending on the program being executed, a constant or variable speed of movement of the end of its RO 3 along the trajectory 6 from point A to point B with an already defined (possibly variable) force F _T and moment M _T effect of this RO 3 on the OR is set 5. The program values of generalized coordinates, their velocities and accelerations, as well as external moments, generated for each degree of mobility of MM 2, are fed to the inputs of position-force control systems (Filaretov V.F., Zuev A.V., Gubankov A.S. Control manipulators when performing various technological operations. - M.: Nauka, 2018. - pp. 93-99) by all MM 2 electric drives, which simultaneously minimize errors both in the position of the output shaft of the gearbox of each MM 2 electric drive, and in the developed external moment. This ensures accurate movement of RO 3 along trajectory 6 with an accurate force effect on OR 5. During this movement, to determine the actual values of the external moments of the MM drives, due to the effect of RO 3 on OR 5 and necessary for the implementation of feedback of these position-force systems, use total values of generalized external moments calculated with the help of diagnostic observers, from which, as noted earlier, the components of mutual influences with real values of masses and moments of inertia of MM links, moments from the action of hydrostatic forces, moments of viscous friction, as well as moments due to the presence of identified attached masses are subtracted and moments of inertia of the fluid.

During the precise movement of the MM 2 along the trajectory 6, the force and moment effects F _D1 , M _D1 , which the MM moving in the aquatic environment exerts on the AUV 1 at the point of its attachment to the latter, are determined. These impacts are calculated using the previously indicated recurrent algorithm for solving the OZD, but this algorithm already uses the identified values of the added masses and moments of inertia of the fluid, as well as the moments of viscous friction that occurs when all the MM 2 links move in the aquatic environment, the moments due to the mutual influences between all links and degrees of mobility of MM, and the values of the vectors of force - F _T and moment - M _T , acting from the side of OR 5 on RO 3 MM.

Simultaneously with the movement of the RO 3 MM 2 along the trajectory 6, not only the above-described target compensation F _D1 , M _D1 by the propellers of the AUV 1 is provided, which in reality may not be entirely accurate, but they also use additional stabilization of the position and orientation of the AUV 1 in the ASC using the installed it contains typical servo control systems, which, due to the introduction of negative feedbacks over all its degrees of freedom with the help of STZ 4, allows minimizing all errors, as well as inaccuracies in determining and working out real F _D1 , M _D1 AUV propulsors.

Claims (1)

Method for position-force control of an autonomous uninhabited underwater vehicle with a multistage manipulator in the mode of its hovering and preliminary stabilization before the start of power operations with the object of work, which are carried out in the future, taking into account the linear displacements of the underwater vehicle in space, determined by the technical vision system, and its angular displacements determined by onboard gyroscopic sensors, which consists in setting variable desired values and directions of force effects exerted by the manipulator working body, the base of which is fixed under the center of magnitude of the underwater vehicle, on the object of work at each point of the trajectory of its working body, which is formed using a 3D model this object of work, while the inputs of the corresponding propellers of the underwater vehicle are supplied with control signals that reduce its deviations from the initial position when the manipulator moves in a viscous medium, characterized in that the outer body of the underwater vehicle is symmetrical about its main vertical axis in the form of an ellipsoid flattened along this axis, and the projection of this body on a plane passing through the other two main axes of symmetry, has the shape of a circle, and six propellers of the underwater vehicle are fixed in pairs on its main axes of symmetry at the same distance relative to its center of magnitude so that the axes of their thrusts in pairs are always are perpendicular to the axes of the thrust of the remaining pairs of propellers and provided the underwater vehicle with six degrees of freedom, the kinematic scheme of the manipulator of the underwater vehicle also has six degrees of freedom, three of which are portable and three are orienting, it enables its working body to provide any spatial orientation of the force and moment action vectors on the objects of work, before the start of any work operations during the test movements of the manipulator with the body of the underwater vehicle fixed in space, using the Kalman filter, the masses and moments of inertia of the surrounding fluid are identified, attached to the two main links of the portable degrees of freedom of the manipulator, after the approach of the underwater vehicle and its stabilization near the object of work, by identifying the current spatial location of the underwater vehicle and the starting point of the formed trajectory using the technical vision system and three markers, as well as knowing the initial location of the manipulator, after solving the inverse problem of kinematics, the laws of change in time of all its generalized coordinates are determined, after which transfer the working body of the manipulator from the initial position to the starting point of the trajectory, synchronously as a function of time, giving signals corresponding to the specified laws of change in generalized coordinates, to the inputs of the servo drives of all degrees of freedom of the manipulator, ensuring a smooth transfer of its working body from the initial position to contact with the object in the initial at the point of the formed trajectory, at the same time, according to the well-known recurrent algorithm for solving the inverse problem of dynamics, taking into account the previously identified added masses and moments of inertia of the liquid, in real time, the force and moment effects on the underwater vehicle from this manipulator moving in the aquatic environment are calculated, which are compensated by a smooth change thrusts of its respective propellers, stabilizing the underwater vehicle at a given point in space, after detecting the contact of the working body of the manipulator with the object of work by a typical tactile sensor, using recurrence relations, taking into account the current configuration of the manipulator, determine the laws of change in time of the desired thrusts of the corresponding propulsors of the underwater vehicle and the desired external moments in all joints of the manipulator, with the help of which, also as a function of time, the desired values of the input signals to the corresponding propellers of the underwater vehicle and the manipulator drives are formed, the synchronous implementation of these signals ensures a smooth increase from zero to the final value of the program force and moment effects from the working body on the object work at the beginning of the trajectory, while maintaining the original current configuration of the manipulator unchanged, while providing more accurate stabilization of the position and orientation of the underwater vehicle in the absolute coordinate system due to the compensation of smoothly increasing force and moment effects from the manipulator by its propellers, the actual inaccuracies of the specified software compensation are eliminated using a typical stabilization system that uses information received from the vision system, and negative feedbacks for all degrees of freedom of the underwater vehicle, using this system, create additional control signals for the corresponding propulsion devices that keep the underwater vehicle at its initial point in space with its initial orientation, after the formation of the initial vector of force action from the side of the working body of the manipulator on the object of work, a new value and direction of this vector is formed, which already takes into account additional components of dry friction and resistance to movement of the working body at the beginning of the constructed trajectory, this vector is also formed using the propulsion of the underwater vehicle by supplying smoothly and synchronously changing input signals to the corresponding propulsors and drives of the manipulator, after constructing the mentioned vector, depending on the program being executed, the speed of movement of the working body of the manipulator along the previously formed trajectory is set and this movement is started by applying the appropriate signals to the inputs of the position-force control systems of the manipulator drives, which include program and actual values of the generalized coordinates of the manipulator, their velocities and accelerations, as well as program and actual values of external moments, due only to the force interaction of the working body of the manipulator with the surface of the work object, and the actual values of these external moments are determined using diagnostic observers of the total values of generalized external moments, from which the components of mutual influences with real values of masses and moments of inertia of the manipulator links, moments from the action of hydrostatic forces, moments of viscous friction, as well as moments due to the presence of already identified added masses and moments of fluid inertia, are subtracted during the movement of the manipulator along of the formed trajectory determine the force and moment effects that the manipulator moving in the aquatic environment exerts on the underwater vehicle at the point of its attachment to the latter, these effects are calculated using a recurrent algorithm using the identified values of the attached masses and moments of inertia of the fluid, the moments of viscous friction arising from movements of all links of the manipulator in the aquatic environment, the moments of mutual influences between all degrees of freedom of the manipulator, as well as the forces and moments acting from the side of the object of work on the working body of the manipulator, all these effects on the underwater vehicle are synchronously and smoothly compensated by its propulsors, while due to inaccuracies in determining some parameters of force effects additionally use the said system for stabilizing the position and orientation of the underwater vehicle in the absolute coordinate system, with the help of which additional signals for controlling its propulsion are formed.

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