19 results about "Rotation velocity" patented technology

The invention relates to a biaxial rotation inertial navigation error modulation parameter selection method based on an error propagation equation, and belongs to the technical field of inertial navigation, and the method comprises the following steps: S1, constructing a biaxial rotation inertial navigation error propagation equation considering an error modulation effect; s2, setting a transposition sequence of the biaxial rotation inertial navigation; s3, based on the error propagation equation constructed in the step S1 and the transposition sequence set in the step S2, obtaining navigation errors at different rotation speeds and navigation errors at different rotation stopping time; and S4, determining the optimal rotation speed and rotation stop time based on the navigation errors at different rotation speeds and the navigation errors at different rotation stop time obtained in the step S3. The method improves the navigation precision of double-shaft rotation inertial navigation, is simple to operate, low in time consumption, low in cost, good in selection effect, high in navigation precision and good in practicability, and solves the problems of long time consumption, high cost, poor selection effect and low navigation precision of the existing empirical method.

Rotating structure (4) for civil applications, comprising - a fixed part (8) and a movable part (12) which rotates about an axis of rotation (XX) and is equipped with drive means (16) for its rotation about the axis of rotation (XX), - wherein the fixed part (8) and the movable part (12) are coaxial with respect to the axis of rotation (XX), - wherein the drive means (16) are arranged on an outer diameter of the movable part (12) antipodal to the axis of rotation (XX), - wherein the fixed part (8) and the movable part (12) are connected to each other at an inner circular interface (20), corresponding to an inner diameter on the side of the axis of rotation (XX), and at an outer circular interface (24), corresponding to an outer diameter, opposite the inner diameter along a radial direction (RR) perpendicular to and intersecting the axis of rotation (XX), - wherein the rotating structure (4) comprises a first position band (28) with indices and at least one first position encoder (32) configured for optical reading of the first position band (28) in order to provide a measurement of the angular position of the moving part (12), or encoder - wherein the rotating structure (4) comprises a first velocity band (36) with indices and at least one first velocity encoder (40) configured for optical reading of the first velocity band (36) in order to provide a measurement of the angular velocity of the moving part (12), - wherein the first position band (28) and the first position transmitter (32) are arranged according to the inner circular interface (20), - wherein the first speed band (36) and the first speed sensor (40) are arranged according to the outer circular interface (24), - wherein the first speed sensor (40) and the first position sensor (32) are functionally connected to the drive means (16) to enable feedback control of the drive of the drive means (16).

The invention relates to a method for commissioning a sensor unit (16), comprising an acceleration sensor and / or tilt sensor, which is / are connected to a motion unit (10) in any mounting orientation, and wherein the method comprises the following commissioning steps to perform a translational axis calibration of a sensor coordinate system (x1, y1), (x3, y3): performing a translational movement of the motion unit (10), acquiring the acceleration and / or rotational velocity values ​​occurring during the translational movement in order to determine a motion vector (x2, y2), (x4, y4), teaching in a correction factor to transform an axis of the original sensor coordinate system (x1, y1), (x3, y3) in the direction of the determined motion vector (x2, y2), (x4, y4).

To reduce the effects of bias error superposition in gyro sensors and the effects of unexpected disturbances, to estimate an SF error of the gyro sensors in real time, robustly, and with high accuracy, and to calculate attitude information of a moving body in real time, robustly, and with high accuracy.SOLUTION: An SF error estimation unit 4 subtracts a calculated value ra (close to a true value ωtrue) of a "rotation speed" of a moving body using observation information of GNSS receivers R1 to R3, from a calculated value rgyro (which deviates from the true value ωtrue) of a "rotation speed" of the moving body using angular velocity information ωgyro of a gyro sensor G, to estimate an SF error rωtrue of the gyro sensor G. A process noise adjustment unit 5 adjusts a "process noise" of a state equation of a state space model related to attitude information "a" of the moving body to be larger or smaller, as a square value of the estimated SF error rωtrue of the gyro sensor G is larger or smaller, respectively.SELECTED DRAWING: Figure 4

The application provides an image acquisition method and device, a terminal device and a computer readable storage medium. The method comprises: acquiring a speed deviation of a second carrier, the speed deviation being an angular velocity of the second carrier relative to a rotating object; determining a target angular velocity of a first carrier according to the speed deviation and a preset initial motion speed of the second carrier; adjusting a current angular velocity of the first carrier to the target angular velocity, and controlling an image sensor to acquire an image of the rotating object. The image acquisition method provided by the application can acquire the speed deviation of the second carrier carrying the first carrier, thereby adjusting the rotating speed of the first carrier, so that the image sensor carried on the first carrier can work at a stable rotating speed, and the quality of the acquired image is improved.

The application discloses a level environment self-adaptive error compensation algorithm method and device, belongs to the technical field of surveying and mapping services; for solving the problem of measurement jump, lag and overshoot caused by coupling of rotation speed change and angle switching under dynamic working condition. The method comprises the following steps: collecting angular velocity and angle switching data in real time; preprocessing and extracting speed change trend and switching time sequence; constructing a segmented adjustable response characteristic mapping based on double driving variables; combining historical deviation distribution and deviation mode characteristics to correct and fuse the initial compensation value; confirming the effectiveness of the compensation parameters through simulation verification; generating compensation instructions synchronized with the response of intelligent sensors by using time alignment mechanism; finally realizing closed-loop parameter updating based on feedback. The application adaptively adjusts the compensation parameters by sensing the speed change and switching action, significantly improving the measurement continuity, stability and overall accuracy of the level in the dynamic environment.

When the absolute value (|Tt−Tc|) of the difference between the turning time Tt of a log PW and the transport time Tc of the log PW is longer than a reference measurement time Ts, the turning-axis center line measurement time Tm is set to the absolute value (|Tt−Tc|) (Step S120), the rotation speed W of centering spindles 24a and 24b is set to a speed (Ws×Ts / Tm) lower than a reference rotation speed Ws, and also the measurement rotation angle α is set to an angle (αs×Ts / Tm) smaller than a reference measurement rotation angle as (Step S122). When the absolute value (|Tt−Tc|) is equal to or less than the reference measurement time Ts, the turning-axis center line measurement time Tm is set to the reference measurement time Ts (Step S116), the rotation speed W of the centering spindles 24a and 24b is set to the reference rotation speed Ws, and also the measurement rotation angle α is set to the reference measurement rotation angle αs (Step S118).

The invention discloses an ISAR (Inverse Synthetic Aperture Radar) image rotation speed estimation method based on sequence continuity, which depends on a SeqFormer network architecture and is combined with a decomposable instance query mechanism and a cross-frame feature modeling strategy to fully mine rotation consistency and geometric relevance between adjacent frames. According to the method, the rotation dynamic constraint is established among multiple frames of images, so that unified modeling and accurate analysis of continuous rotation features of the target are realized. In the feature extraction stage, a cross-frame feature interaction and fusion mechanism is utilized, the problem of local structure discontinuity caused by noise and shielding is effectively weakened, the morphological integrity of a target in a time sequence is kept, and stable geometric support is provided for rotation estimation. Furthermore, modeling and regression learning are carried out on rotation difference features between adjacent frames, the network can directly output the rotation speed of the target, the complex process depending on calibration or key point matching in a traditional method is avoided, and estimation precision and stability are remarkably improved.

The application discloses a table tennis rotation estimation method based on a motion trajectory and application thereof, and the method comprises the following steps: 1, fitting the relationship between the Magnus force coefficient and the linear velocity and angular velocity of the ball; 2, based on the fitting relationship between the Magnus force coefficient and the linear velocity and angular velocity of the ball, a linear equation group of the direction of the angular velocity vector is constructed by using a new trajectory of the table tennis flight, and the direction angle of the table tennis rotation angular velocity vector is obtained by solving the linear equation group; 3, based on the direction of the table tennis rotation angular velocity vector, a nonlinear function of the rotation angular velocity module is constructed by using the new trajectory of the table tennis flight, and the minimum value of the nonlinear function is solved to obtain the module of the table tennis rotation angular velocity. The application can accurately estimate the rotation speed of the ball in flight, thereby improving the precision of the table tennis trajectory prediction.

Method for estimating angular errors of coders in a looped system including a rotating actuator, an angle coder producing a position measurements, and a calculation device controlling the actuator, said device receiving a setpoint signal and the position measurements, for looping, and calculating in a corrector a control signal. In a test phase, a specific corrector Cω<sub2>rj< / sub2>(q) is synthesised for a constant rotation speed ωrj, the corrector having zero gain at the corresponding frequency and harmonics, resulting in opening the loop, a matrix relation is established between position measurements and a function of parameters characterizing coder errors and torque ripples, the test phase repeats with different rotation speeds, the matrix relations are concatenated producing an identifiable global matrix relation, the parameters are estimated by resolution of the global matrix relation.

The present application belongs to the technical field of wind tunnel test, and particularly relates to a precession simulation device for a helical flutter wind tunnel test. The present application solves the problem of designing a helical flutter wind tunnel test device for a rotorcraft, and studies key influencing parameters and influencing rules of the helical flutter of the rotorcraft by designing a precession motion simulation device for the rotorcraft. The present application can realize the rotation of the rotor in the wind tunnel, and adjust the rotation speed of the rotor through a motor. Meanwhile, the precession system realizes the decoupling of the pitch and yaw modes of the rotation shaft, and the pitch and yaw mode frequencies are independently adjustable. Meanwhile, the axes of the pitch and yaw axes coincide, so that the precession motion of the pitch and yaw degrees of freedom can be realized under the action of the gyroscopic moment. Meanwhile, the adjustment of the rotation inertia of the nacelle rotating mass, the weight and the center of mass of the nacelle can be realized. Finally, the rotation speed of the rotating mass such as the rotor and the hub can be adjusted through the speed regulation motor, so as to ensure the matching of the rotation speed and the incoming flow speed, and achieve the helical flutter state.

An angle error correction device includes an actual rotation angle measurement circuit that converts a rotation angle information of a rotation angle detection target to an angle counter value for each predetermined angle; an actual speed calculator that calculates an actual rotation speed for each predetermined angle from the angle counter value; a curve interpolation circuit that generates a curve interpolation equation from the angle counter value; an ideal speed estimator that calculates an estimated ideal rotation speed for each predetermined angle using the curve interpolation equation; an angle error detector that calculates an angle error for each predetermined angle by integrating an angle ripple ratio determined by the actual rotation speed and the estimated ideal rotation speed; an angle error table in which the angle error calculated by the angle error detector is stored; and a correction circuit that corrects the rotation angle information using the angle error table.

The invention relates to the technical field of experimental equipment, in particular to a dynamic shear friction experimental device which comprises a thrust unit capable of pushing an impact rod in the extension direction of the impact rod; the loading rod and the impact rod are coaxially arranged, the first end of the loading rod is provided with a first waveform shaper, and the impact rod can impact the first waveform shaper; the loading rod can impact the second waveform shaper and push the incident rod group to rotate around the central axis of the incident rod group; a sample group can be fixed and clamped between the incident rod group and the transmission rod, and the axial pressure assembly can apply a pushing force for pushing the transmission rod to face the incident rod group. In this way, the problem that control over the pulse duration, amplitude, rotation speed and waveform profile of incident waves in an existing dynamic shear friction experiment is limited greatly is solved, and particularly, the problem that shear and friction behaviors of materials cannot be accurately obtained at the high strain rate is solved.

The application discloses a kind of tropical cyclone evolution whole process three-dimensional wind field wind tunnel simulation device, system and method, the simulation device of the present application, the rotation angle and rotation speed of transverse blade structure are adjusted by driving mechanism, can make air flow after the flow guide of flow guide structure form the wind speed profile in line with the characteristics of tropical cyclone field;The guide angle of vertical blade structure at different heights is adjusted by driving mechanism, and the average wind profile in the wind tunnel and the twist of air flow direction can be changed.The simulation device and simulation system of the present application can realize various wind tunnel effects, including making guide angle change with height as exponential function law, making wind speed twist angle reach maximum on ground, etc., and it is convenient and fast to operate, can effectively improve experimental efficiency, simultaneously has the advantages of low implementation cost, strong use flexibility, high space utilization.

The invention relates to the technical field of air fryer simulation, in particular to an air fryer fan fluid simulation analysis method based on Fluent software, which comprises the following steps: S1, establishing a model; s2, carrying out meshing processing on the geometric model; s3, selecting a k-epsilon turbulence model of an RNG equation in the ANSYS Fluent; s4, adding the air densities and the air viscosities at different temperatures into the ANSYS Fluent; s5, setting a rotation speed, a rotation coordinate and a rotation direction of a rotation domain; s6, torque required by rotation of the fan is set in the monitor, so that the magnitude and the change trend of the torque are detected and recorded in real time during calculation; and S7, setting flow field initialization parameters according to the calculation working conditions. And S8, starting to calculate and solve, and calculating the power required by the converged fan fluid. The method has the beneficial effects that the temperature effect is considered during design, a more practical and accurate calculation result can be obtained, and fan parameters can be accurately optimized.