36 results about "Viscous friction" patented technology

The invention is suitable for the field of tracking rotary tables, and provides a tracking rotary table follow-up adjustment control system and method based on dynamic identification, and the method comprises the steps: building a discretization mathematical model of a tracking rotary table servo system; running a recursive least square algorithm with a variable forgetting factor by using the collected running state data; the equivalent rotational inertia and the total viscous friction coefficient are obtained based on identification; adjusting the gain of a feedback controller in real time according to the equivalent rotational inertia obtained by identification and a preset system closed-loop bandwidth index; carrying out superposition synthesis on the feedforward compensation torque and the feedback control torque, and carrying out parameter validity verification and amplitude safety verification on the synthesized control quantity to generate a motor driving signal for driving a tracking turntable to eliminate tracking errors; by means of variable forgetting factor identification and a composite control strategy, the problems of load time varying and nonlinear interference are solved, bandwidth constant keeping and zero phase lag tracking are achieved, and dynamic response and steady state precision are remarkably improved.

The invention relates to the technical field of intelligent inspection of rail transit, and discloses a compensation method for joint friction force of a mechanical arm of a metro underbody inspection robot, which comprises the following steps of: acquiring angular velocity, angular position and temperature data in real time through a joint angle and temperature sensor, and establishing an improved LuGre friction force dynamic model; a temperature correction term is introduced to accurately characterize coulomb friction, viscous friction and a Stribeck effect. A recursive least square algorithm is adopted to realize online identification of model parameters, a predicted friction force compensation item is introduced into a servo control loop, and unmodeled disturbance correction is realized in combination with PID control, sliding mode control and an extended Kalman filter. And in the low-speed interval, a gain coefficient is adopted to enhance friction compensation and inhibit joint crawling. According to the method, trajectory tracking errors can be remarkably reduced in a complex environment, and the operation stability and detection precision of the inspection robot are improved.

The invention discloses a self-adaptive identification and compensation method for friction nonlinear characteristics of a feeding system of a numerical control machine tool. According to the method, parameters of a LuGre friction model are initialized by collecting an actual position signal, an actual speed signal, an actual current signal and an instruction position signal of a feeding system; friction parameter self-adaptive identification is carried out based on motion state segments, coulomb friction parameters and viscous friction parameters are updated by adopting a least square method in a constant speed stage, and bristle rigidity parameters, bristle damping parameters and Stribeck speed parameters are updated by adopting an extended Kalman filter in an acceleration stage and a deceleration stage; generating a friction force estimation value according to the identified friction parameter, converting the friction force estimation value into a compensation current signal, and adding the compensation current signal to a servo driver current instruction after phase lead compensation. According to the method, the friction characteristic change can be adaptively identified on line, tracking errors and vibration caused by friction nonlinearity are effectively inhibited, and the machining precision and stability of the numerical control machine tool are improved.

The application discloses a kind of industrial robot dynamics identification method with nonlinear viscous friction, it is related to robot dynamics modeling and control field.The method is considered in robot modeling, nonlinear term of viscous friction, different from traditional coulomb viscous friction model, its content includes robot friction model construction, excitation trajectory model selection, parameter optimization and dynamics parameter solving.In excitation trajectory selection optimization, the trajectory model of five order Fourier series and five polynomials is selected, and the genetic algorithm with penalty function is used to optimize the parameters of excitation trajectory;In solving process, based on interior point method, iteration fitting is carried out, and complete dynamics parameters of robot are obtained.The friction model considered in the application has higher modeling accuracy, and the problem of system jitter at start and end position is overcome, the efficiency and accuracy of robot dynamics parameter identification are improved, and can be used in robot mobile handling, polishing and polishing and heavy load hydraulic industrial scene.

This invention relates to the field of bearings, specifically to a noise-reducing bearing with an integrated micro-perforated plate sound-absorbing structure. Rolling elements are disposed between the inner and outer rings of the bearing, and these rolling elements are positioned at intervals by a cage. A sealing ring is disposed on one side of the outer ring. The sealing ring has a mounting structure for installing the micro-perforated plate. The micro-perforated plate is annular and installed at the sealing ring, with a uniform array of micropores. An air cavity is formed between the micro-perforated plate and the sealing ring, constituting the back cavity of the sound-absorbing structure. In this invention, by setting a micro-perforated plate sound-absorbing structure at the bearing's sealing structure, the bearing maintains its original sealing function while possessing active sound absorption capability. When noise generated during bearing operation propagates to the micro-perforated plate, sound waves enter the micropores, generating viscous friction and heat exchange between the air and the pore walls within the micropore channels, thereby converting some of the sound energy into heat energy and dissipating it.

The invention provides a motor rotational inertia identification method and device, electronic equipment and a storage medium, and relates to the technical field of automobiles. The method comprises the steps that a motor is driven to rotate according to a preset sine rotating speed instruction, and the motor output torque and the actual rotating speed of the motor are obtained; acquiring a motor output torque and a motor actual rotating speed; obtaining a differential signal of the actual rotating speed of the motor according to the actual rotating speed of the motor and a preset tracking function; and obtaining the rotational inertia of the motor according to the differential signals of the motor output torque and the actual rotating speed of the motor and the motor motion equation. According to the method, the load torque and the viscous friction torque in the motor motion equation are eliminated by utilizing the periodicity characteristic of the sine rotating speed instruction, the fundamental wave characteristic of the sine rotating speed instruction is tracked by utilizing the preset tracking function, and the effective signal of the actual rotating speed of the motor is extracted, so that the identification accuracy and stability of the rotational inertia of the motor are improved.

The application discloses a robot friction parameter identification method and device, a terminal and a medium. The method comprises the following steps: acquiring a dynamic speed threshold of a robot joint; identifying a static friction coefficient, a coulomb friction coefficient and a critical speed in a low-speed section where the speed of the robot joint is lower than the dynamic speed threshold; and identifying a viscous friction coefficient in a medium-high speed section where the speed of the robot joint is higher than the dynamic speed threshold, in combination with the obtained static friction coefficient, the coulomb friction coefficient and the critical speed. The application has the advantage that higher-precision robot friction parameters can be obtained, thereby facilitating the construction of a high-precision robot friction model.

The shock absorption structure of the submersible pump for the coal mine machine comprises a base, the top of the base is fixedly connected with a pump body, and the outer portion of the pump body is fixedly connected with a connecting base; the damping assembly comprises two damping rods, and the two damping rods are both fixedly connected to the bottom of the base; and the protection assembly comprises a steel mesh. When the device is used, the device is firstly mounted at a proper position, and the two damping rods are utilized based on the physical effect of damping. When an object is subjected to external force, vibration energy can be gradually converted into heat energy due to factors such as viscosity, friction and deformation of a medium, the vibration amplitude can be reduced in cooperation with a buffer spring, in the daily use process after installation, broken stones falling from the outside can be prevented from directly hitting the pump body through the protection frame, and the overall protection effect on the pump body is improved; and the durability and the stability of the whole device in the using process are improved.

The utility model provides a composite sound absorption structure and a vehicle provided with the composite sound absorption structure, the composite sound absorption structure comprises a perforated plate, a sound absorption part and a support part; a gap exists between the sound absorption part and the perforated plate, a square containing cavity is defined by the micro-perforated plate in the sound absorption part, and the honeycomb filler is arranged in the square containing cavity; the perforated plate is provided with a plurality of through holes to form a sound transmission channel in the compartment body, so that noise reaches the sound absorption component connected with the perforated plate through the through holes, the micro-perforated plate of the sound absorption component is a direct reflection surface of the noise, and sound waves consume energy due to a viscous friction effect when passing through micropores of the micro-perforated plate. Cavities and micropores in the honeycomb filler form resonance sound absorption; and compared with a single-layer micro-perforated plate which can only cover low and medium frequency sound, the micro-perforated plates encircle to form the square accommodating cavity to form three groups of double-layer micro-perforated plate structures, namely an up-down double-layer micro-perforated plate structure, a left-right double-layer micro-perforated plate structure and a front-back double-layer micro-perforated plate structure, so that the sound absorption frequency band can be expanded to

The application discloses a kind of power transformer internal inspection robot fault diagnosis and monitoring method, it is related to motor control field, comprising: collecting motor ambient temperature, shell temperature, three-phase stator current and power consumption parameters, extract negative sequence intrinsic current component and construct heat dissipation barrier factor, generate negative sequence suppression attenuation coefficient to correct original negative sequence compensation voltage instruction, inhibit abnormal heating, for torque drop, based on the coefficient and static viscous friction threshold value calculation static friction torque gap, calculate negative direct-axis field-weakening current component to carry out thrust compensation, utilize extended back electromotive force online observation flux linkage amplitude, and generate dynamic limiting amplitude extreme value in combination with safety threshold to clamp direct-axis field-weakening current, based on presequence calculation parameter generation fault diagnosis and health monitoring data.The application realizes the collaborative balance of heat accumulation inhibition, thrust maintenance and permanent magnet demagnetization protection, guarantees the continuous safe operation of robot under fault state.

The utility model discloses a high vacuum solenoid valve which comprises a valve body and an electromagnetic control device, the valve body is provided with a flow channel, the electromagnetic control device is internally provided with a static iron core and a movable iron core which movably blocks the flow channel, the movable iron core is sleeved with a guide pipe, the end portion opposite to the static iron core is provided with a spiral groove, and the end, facing the valve body, of the movable iron core is provided with a rivet ring. The rivet ring is internally provided with an anti-leakage gasket which abuts against the end portion of the movable iron core. According to the high-vacuum electromagnetic valve, the structural framework arrangement is optimized, assembling is facilitated, the sealing performance is improved, the guide pipe is arranged on the outer side of the movable iron core, the QPQ processing technology is conducted on the guide pipe, outer surface processing is conducted on the guide pipe, the abrasion resistance is improved, the starting performance is better, the spring abuts against the end of the movable iron core, and the spiral groove is formed. The spiral dimpled grains enhance electromagnetic force through the edge magnetic field concentration effect in the initial stage of movement, viscous friction is reduced, the response speed is increased, and the electromagnetic iron core responds faster.

The invention relates to the technical field of computers, in particular to a variable damping control method and device based on a continuous friction model. The method comprises the following steps: acquiring construction parameter data of a continuous friction model; wherein the constructed parameter data comprises a nonlinear dynamic coefficient, coulomb friction, maximum static friction, turning speed, a viscous friction coefficient and an actual rotating speed of the motor; constructing a continuous friction model based on the construction parameter data; based on a continuous friction model, determining a differential function of friction torque to speed; determining a variable damping coefficient based on the differential function of the friction torque to the speed and a preset adjustment principle of an additional damping coefficient; determining the voltage of a permanent magnet synchronous motor of the space optical pointing servo system based on the variable damping coefficient; and controlling the permanent magnet synchronous motor of the space optical pointing servo system based on the voltage of the permanent magnet synchronous motor. Through the configuration mode, the control precision of the space optical pointing servo system can be improved.

This invention discloses a linear motor friction compensation method combining model feedforward and observer, belonging to the field of linear motor friction compensation. The invention addresses the problem of frictional abrupt changes in existing permanent magnet synchronous linear motors during positive and negative velocity crossings, where the Stribeck friction model leads to overcompensation. The method includes: calculating the current static frictional force F based on the current mover velocity v. f Take the current static friction force F f The friction force feedforward compensation is calculated as 0.5 times the current value. Simultaneously, an observer estimates the viscous friction force compensation as an auxiliary compensation for the current static friction force based on the q-axis current command and the current actual position of the mover. The friction force feedforward compensation and viscous friction force compensation are converted into a compensation current and then superimposed with the current control command output by the position loop controller to obtain a compensated current control command, which is then input to the current loop. This invention is used for friction force compensation in linear motors.

The invention discloses a truss manipulator zero-force dragging teaching method, which comprises the following steps of S1, building a truss manipulator kinetic model: obtaining parameters including gravity torque, static friction force and viscous friction coefficient by building a single-axis kinematics model of a truss manipulator; s2, designing an action process, and identifying each parameter of the kinetic model; and S3, compensating torque output required during mechanical movement according to the obtained identification parameters, and realizing zero-force dragging. The invention provides a zero-force dragging teaching method for a truss manipulator, which can enable an operator to enable the manipulator to move along an expected running track in a dragging manner, and after the dragging is finished, a system records the motion track during the dragging motion of the manipulator and reproduces the motion track during automatic running. Therefore, an operator only needs to understand the action technological process of the manipulator and does not need to have programming skills, application of the manipulator can be achieved, and the operation process is simplified.

This invention discloses a shock-resistant relay, relating to the field of relay technology. It includes a base body with an electromagnetic system assembly mounted on its top. In use, the shock-resistant pad isolates the electromagnetic system assembly and the shock-absorbing plate from the base body, absorbing some of the vibration energy. Vibration energy is dissipated through the viscous friction of a liquid magnetorheological fluid. The negative Poisson's ratio honeycomb panel has a negative Poisson's ratio honeycomb structure, with highly elastic silicone rubber filling the honeycomb cells to disperse the impact load transmitted by the base body. Through the tensile effect, it achieves three-dimensional vibration energy absorption. A piezoelectric ceramic sheet converts mechanical vibration into electrical energy to power the excitation coil, achieving "self-harvesting of vibration energy." After the excitation coil is energized, the magnetorheological fluid transforms into a near-solid-state damping layer, improving the shock resistance in complex vibration environments. Dynamic shock absorption is achieved through the switching between liquid and solid states of the magnetorheological fluid.

The utility model relates to the technical field of bearing machining, in particular to an efficient heat dissipation bearing lubricating device which comprises a workbench, a lubricating table is fixedly connected to one side of the workbench, a conveying sliding way is fixedly connected to the outer wall of the workbench through a supporting base, a sliding groove is formed in the conveying sliding way, and an L-shaped conveying belt is arranged in the sliding groove. And a plurality of bearings are placed in the L-shaped conveying belt. The micro heat pipe is arranged above the bearing seat, so that heat generated by viscous friction during bearing lubrication can be transferred out, the heat sequentially passes through the evaporation section, the heat insulation section and the condensation section of the micro heat pipe, and steam is condensed, refluxed and circularly radiated under the action of cold air of the cooling box and the radiating fins; compared with a traditional air cooling heat dissipation mode which is low in heat dissipation efficiency, complex in liquid cooling structure and prone to leakage, the heat dissipation mode is efficient and stable, the surface temperature of the bearing can be effectively kept stable, lubricating grease performance reduction caused by high temperature is avoided, and it is ensured that the lubricating effect is lasting and good.

The present application relates to the technical field of unmanned aerial vehicle flight control, and relates to an unmanned aerial vehicle wind resistance adaptive control method based on real-time environment sensing, which comprises issuing a desired rotating speed instruction to an electronic speed regulator according to an attitude control loop, synchronously acquiring actual quadrature axis current and absolute physical acquisition time; extracting a quadrature axis current sequence to identify and update rotor aerodynamic drag coefficients and motor viscous friction coefficients; combining the identified coefficients to calculate a desired quadrature axis current and construct a time domain reference sequence, deducing a synchronous desired quadrature axis current and subtracting the actual quadrature axis current, mapping actuating current residuals into single-rotor disturbance torque residuals; inverting a three-dimensional wind speed vector of the machine body and using a confidence decay coefficient to correct and generate an effective wind field vector; calculating a dynamic weighted feedforward control vector and fusing it with a feedback control vector to solve a desired angular velocity instruction and execute wind resistance control. The present method does not require a physical anemometer, and can realize environment wind field sensing and adaptive feedforward compensation only by online identification of underlying electrical data and parameters.

The application discloses a kind of calculation methods of friction torque of planetary roller screw pair, comprising: establishing roller thread load distribution model;Solving the contact characteristic index of planetary roller screw pair;Calculate the elastic hysteresis friction torque caused by elastic deformation hysteresis before and after rigid body loading and unloading;Calculate the spin slip friction torque caused by the fact that the actual rotation axis of roller is not perpendicular to the common normal of contact surface;Calculate the differential slip friction caused by the relative sliding between screw, roller and nut;Calculate the lubricant viscous friction torque caused by the surface viscous force of lubricant;Iterate the above friction torque to obtain the friction torque of the whole planetary roller screw pair.The thread load distribution law and contact characteristics of the planetary roller screw pair can effectively and accurately derive each part friction torque, which can effectively improve the transmission efficiency of the planetary roller screw pair, and has guiding significance for the parameter design of the planetary roller screw pair.

The application discloses a gas-floating type turbine cylinder pawl structure suitable for deep peak regulation and relates to the technical field of turbines.The gas-floating type turbine cylinder pawl structure comprises a cylinder, a pawl fixed to the side wall of the cylinder and a supporting platform, and a gas-floating gasket assembly is arranged between the pawl and the supporting platform; the gas-floating gasket assembly comprises a gas-floating gasket body fixedly connected with the pawl, a solid cavity is formed in the gas-floating gasket body, and a porous disc is arranged at the bottom of the gas-floating gasket body. The gas-floating gasket assembly is arranged between the pawl and the supporting platform, high-pressure air is introduced into the solid cavity, the high-pressure air is uniformly discharged through the porous disc to form a micron-level air film, traditional dry friction is changed into gas viscous friction, the friction force is reduced by more than 95%, the overturning force of the bearing box caused by the friction jam when the cylinder is heat-expanded is eliminated, and the temperature rise of the bearing bush and the abnormal wear failure of the shaft seal are avoided from the root.

The invention relates to the technical field of centrifugal pumps, and discloses an anti-blocking multistage energy-saving centrifugal pump which comprises a pump shell, the pump shell comprises an upper shell body and a lower shell body, a first liquid storage cavity is fixedly installed at the upper end of the interior of the upper shell body, and a second liquid storage cavity is fixedly installed at the upper end of the interior of the lower shell body; and inner cylinders are rotationally installed in the upper shell and the lower shell and located below the first liquid storage cavity and the second liquid storage cavity correspondingly, the two inner cylinders are symmetrically arranged, a water inlet pipe is fixedly installed on the outer wall of the upper half portion of the upper shell, and a water outlet pipe is fixedly installed on the outer wall of the upper half portion of the lower shell. According to the multi-stage pressurizing pump, multi-stage pressurizing conveying of water flow in the pump body is achieved through rotation of the multiple sets of impellers, the first protruding blocks and the second protruding blocks are fixedly installed on the outer walls of the tail ends of the blades, vortex and flowing separation of water flow at the tail ends of the blades can be restrained, and hydraulic losses are reduced; and meanwhile, the blade surface flow state can be adjusted, and mechanical energy loss caused by viscous friction resistance is reduced.

The application relates to the technical field of robot driving control, and discloses a high-precision driving control method and system for a dexterous hand, which comprises the following steps: collecting end voltage, phase current, rotor angular velocity and external contact force signal of a microminiature hollow cup motor; obtaining a coil resistance estimation value and an inverse electromotive force coefficient estimation value based on the end voltage and the phase current by using an extended Kalman filtering algorithm; mapping the coil resistance estimation value into a viscous friction coefficient evolution value, and mapping the external contact force signal into a Coulomb friction torque correction value; combining the rotor angular velocity to calculate a total friction compensation torque; and normalizing a total electromagnetic torque target value after superposition by using the inverse electromotive force coefficient estimation value to generate a driving current instruction. The application solves the problem of a thermal compensation blind area of a micro driving module without a temperature sensor, and realizes high-precision force and position control of the dexterous hand under complex working conditions with variable temperature and variable load.

This invention discloses a bearing thermo-mechanical coupling analysis method based on finite element thermal networks, comprising the following steps: calculating the initial radial deformation of the bearing under assembly conditions and centrifugal force; considering fluid viscous friction, improving the bearing pseudo-dynamic analysis, and calculating the precise distributed heat generation of the bearing; using the finite element thermal network method, precisely applying heat sources to calculate the refined temperature field of the bearing, its shaft, and bearing housing; based on the discrete temperature field, calculating the comprehensive radial deformation of the bearing under assembly conditions, centrifugal force, and temperature rise, and updating the geometric relationship; updating the heat generation and temperature field through pseudo-dynamic analysis, and iterating through pseudo-dynamic distributed heat generation-temperature field-comprehensive deformation coupling until the lubricating oil outlet temperature converges; outputting the bearing kinematic and dynamic parameters and the bearing temperature field. This invention achieves precise positioning of the bearing heat source and refined temperature distribution of the bearing, its shaft, and bearing housing, providing theoretical guidance for precise thermal analysis in the design and application of high-speed ball bearings.

The invention relates to the technical field of robot control, in particular to a robot joint dynamic parameter identification method based on a CSFM nonlinear friction model and a mixed GWO-PSO algorithm. Comprising the following steps that a dynamic model is built, specifically, the relation between the joint position, speed, acceleration and joint driving torque of a robot operation arm is defined based on a centrosymmetric static friction model, and the robot dynamic model is built; an optimization algorithm: dynamically fusing a particle swarm optimization algorithm and a grey wolf optimization algorithm in stages; dynamic parameter identification: carrying out dynamic parameter identification on the robot dynamical model, firstly generating a motion track through a track generator, then respectively executing the motion track to the robot and the robot dynamical model to generate respective joint torques, inputting an error of the torques of the robot and the robot dynamical model into a target function defined by an optimization algorithm, and carrying out dynamic parameter identification; therefore, dynamic parameters are adjusted and optimized, and dynamic parameter identification is achieved. According to the method, the CSFM model describes the nonlinear friction characteristics of the robot joints, multiple factors such as static friction, coulomb friction, viscous friction and the Stribeck effect are fused, the hysteresis effect is considered, the friction behaviors of the joints under different working conditions can be reflected more comprehensively, and the adaptability to complex motion scenes is remarkably improved.

This invention discloses a friction feedforward compensation method and system for a servo system, comprising: identifying segmented friction force model parameters, including maximum static friction torque, Coulomb friction torque, viscous friction coefficient, and critical Stribeck speed, based on speed feedback signals and utilizing the steady-state response of the servo system to simple input signals; modeling the friction torque of the servo system as a piecewise function of speed according to the model parameters, constructing a segmented friction force model to calculate friction force; using the segmented friction force model as a feedforward compensator, calculating the current feedforward amount in each control cycle and superimposing it on the current loop command; calculating the friction compensation amount online according to the real-time speed command and injecting it into the servo system, working together with the original PI feedback control to offset friction disturbances; this invention, through a simplified segmented static model and parameter identification based on steady-state response, greatly reduces the complexity of the algorithm and the difficulty of engineering implementation while ensuring the compensation effect.

The invention relates to a robot dynamics modeling and parameter identification method considering friction normal force. Comprising the steps of 1, designing a motion track; 2, the friction torque and the contact surface normal force of the robot are extracted; 3, filtering the collected friction torque; 4, establishing a coupling model of the friction force and the contact normal force of the friction surface; 5, identifying parameters of the friction force and contact surface normal force coupling model; 6, designing an excitation track; 7, acquiring the position, speed, acceleration and torque data of the robot, and filtering; 8, a robot dynamic model based on the coulomb viscous friction model is constructed and linearized, and a least square method is adopted for parameter identification; and 9, establishing a robot dynamics model considering the influence of the normal force of the friction contact surface, and carrying out parameter identification. According to the invention, the coupling between the gravity, inertia force and the like of the robot and friction can be solved to a certain extent, and the problem of coupling between the gravity, inertia force and the like of a traditional dynamic model and friction is avoided.

The application discloses a rigid pressure stabilizing device for a petroleum drilling pump and belongs to the field of petroleum drilling equipment. The device comprises a main flow path formed by a connecting end one and a connecting end two connected to the side of the connecting end one. A gas bag buffer is fixed to the outer surface of the connecting end one, and the liquid inlet end of the gas bag buffer is communicated with the connecting end one. An inner cavity is formed in the connecting end two, and the inner cavity comprises a throat part formed in the middle part of the connecting end two. The gas bag buffer is matched with a throttling assembly to realize the pressure stabilizing function. When the pressure peak value comes, part of the fluid is rapidly compressed and absorbed by the gas bag of the gas bag buffer (energy is stored). Another part of the fluid passes through the throttling assembly, and the kinetic energy of the fluid is converted into heat energy through viscous friction and dissipated. When the pressure trough comes, the stored energy in the gas bag buffer is released, the compressed fluid is pushed back to the main flow path, the pressure of the main flow path is effectively supported and improved, and the trough value is compensated.

The invention provides a method for calculating pretightening force of an anti-slip clamping ring of a split bearing. The method comprises the following steps: S1, acquiring working condition parameters and structural parameters of the split bearing; s2, calculating the total friction torque Mf, wherein the total friction torque Mf = the friction torque MI caused by the rotational inertia + the friction torque Mr caused by the external load + the friction torque Mv generated by the viscous friction of the lubricant; s3, the pressure Fd needed for preventing the inner ring and the shaft from generating relative slip is calculated through an integral method; s4, the contact stress P caused by the temperature difference between the clamping ring and the inner ring is calculated; s5, the expansive force FZ, caused by the temperature difference, on a single connecting bolt between the clamping ring and the inner ring is calculated; s6, the pressure Fd and the expansion force FZ are integrated, the axial load PLmax needing to be borne by a single connecting bolt is calculated, and PLmax is the minimum pre-tightening force needed by the clamping ring; when the pretightening force is met, the inner ring of the split bearing and the clamping ring can be ensured not to slip in the operation process; and the pre-tightening force of the clamping ring meeting the condition that the interior of the split bearing does not slip can be solved.

The application provides a mechanical arm dynamics parameter identification method and device and related products. First, a single-joint independent excitation experiment is sequentially performed on N joints of the mechanical arm to obtain N sets of independent excitation data subsets. Then, based on the N sets of independent excitation data subsets, a regression equation with an upper triangular block structure is constructed by extracting torque observation data and a regression vector of a current motion joint, and a block matrix structure of the regression equation with the upper triangular block structure is used to block the reverse propagation of noise to identify a first set of dynamics parameters, which are gravity parameters and Coulomb friction parameters. Then, the first set of dynamics parameters is used to eliminate gravity terms and Coulomb friction terms in the torque measurement data of the mechanical arm, and a dynamics residual equation is constructed to identify a second set of dynamics parameters, which include an inertia tensor and a viscous friction coefficient. In this way, the accuracy of the identification of the dynamics parameters of the mechanical arm is improved.

The present application belongs to the technical field of deepwater exploration of ocean oil and gas, and provides a method for determining a model of viscous friction of a riser after separation and drilling leakage, which is fused with mechanism and data, the method comprising: step S1: obtaining original data, including the pressure difference between the top and bottom of the riser, the liquid column height, the cross-sectional area of the inner wall of the pipe, the flow rate of the liquid in the pipe, and the viscous friction of the leakage liquid of the inner wall of the pipe; step S2: analyzing the data characteristics, analyzing and screening the Top-N key features; step S3: processing and classifying the data, using the Min-Max scaling normalization method to perform data feature standardization operation; step S4: determining and optimizing the data-driven model structure, selecting a randomly configured neural network as the core tool; step S5: training the model, alternately executing the network node growth and Dropout regularization algorithm; step S6: testing the model, verifying whether the Top-N key features on the test data are consistent.

The invention discloses a robot friction compensation and external force estimation method based on an ANFIS, and the method comprises the steps: enabling a joint to walk through a static friction-Stribeck-viscous friction full speed range in a controlled environment, collecting the angular speed and motor torque, carrying out the preprocessing, training an ANFIS model, and obtaining a friction torque estimation value which can be output in real time; introducing the estimated value as feed-forward compensation into a generalized momentum observer, and calculating an external torque initial value; denoising is carried out through median filtering and Butterworth low-pass filtering, and a clean external torque signal is obtained; and finally, establishing an AR (1) noise model under the working condition of no external force, setting a dynamic collision threshold value by using the variance and the safety margin, and judging the collision if the signal exceeds the threshold value. Only a joint encoder and motor current are used in the whole process, an additional force sensor is not needed, and accurate and real-time external force sensing and collision protection can be provided for dragging teaching and man-machine cooperation.