CN102629283A - Simulation analysis method for effects of rotating part on flexible dynamics - Google Patents

Abstract

The invention discloses a simulation analysis method for effects of a rotating part on flexible dynamics. The simulation analysis method includes analyzing features of a large rotating part, and building a dynamic model of the large rotating part; performing structural dynamic analysis to flexible accessories of the large rotating part, generating a linearized vibration model described by a modal coordinate after modal truncation, building a multibody dynamic model with the flexible accessories according to a rigid body dynamic model; building a flexible satellite attitude dynamic and control system model based on the built models, and performing simulation by using the flexible satellite attitude dynamic and control system model; and performing time domain and frequency domain analysis to simulation data to obtain perturbation features. The simulation analysis method can be used not only for conformation of design results in attitude and obit control and dynamic design processes, but also for failure determination and inversion during obit operation. The simulation analysis method for the effects of the rotating part on flexible dynamics solves the practical engineering problem of the effects of the rotating part on flexible dynamics, and has the advantage that stability and reliability of platforms are improved.

Description

A kind of rotatable parts are to the simulating analysis of flexible kinetic effect

Technical field

The present invention relates to Structural Dynamics and dynamics, more particularly, relate to the simulating analysis of a kind of rotatable parts flexible kinetic effect.

Background technology

Development along with modern technologies; Pointing accuracy and degree of stability to satellite; And long-life and high reliability etc. require day by day to improve; Rotatable parts in the satellite and structure flexible appendage coupled vibrations more and more cause people's attention to effect of kinetics, and flexible Dynamic Modeling becomes the important topic that space industry is studied with analysis.

In flight and control procedure; Disturbing force (moment) and control (moment) not only can cause the change of position and attitude; And can evoke the elastic vibration of the flexible appendage in the rotatable parts, the elastic vibration of flexible appendage and then have influence on control accuracy and the load imaging stability of satellite again.The cyclic torque that particularly produces when rotatable parts causes flexible appendage easily and resonates during with the coupling of flexible appendage vibration frequency, has a strong impact on the operate as normal of satellite, can cause the flexible appendage fatigue damage when coupled vibrations is serious even also.Therefore, in dynamic analysis and controlling Design, must analyze and can emulation rotatable parts motion artifacts be coupled with accessory structure is flexible, and to the effect of kinetics degree.But also there is not such method in the prior art.

Summary of the invention

Lack the defective of analyzing when the objective of the invention is to overcome prior art, thereby a kind of simulating analysis accurately and rapidly is provided rotatable parts and flexible appendage generation coupling thereof.

For solving the problems of the technologies described above, the invention provides the simulating analysis of a kind of rotatable parts to flexible kinetic effect, comprising:

Step 1), the characteristic of large-scale rotatable parts is analyzed, set up the kinetic model of said large-scale rotatable parts;

Step 2), to rotatable parts with flexible appendage carry out the Structural Dynamics analysis, through generating the model of vibration that linearizing modal coordinate is described down after the mode truncation, have the many-body dynamics model of flexible appendage in conjunction with the rigid dynamics modelling;

Step 3), in step 1) and step 2) set up Flexible Satellite Attitude dynamics and control system model on the model based set up, utilize this model to carry out emulation;

Step 4), the emulated data that step 3) is obtained are carried out the time-domain and frequency-domain analysis, obtain perturbation features.

In the technique scheme, in described step 1), the kinetic model of said large-scale rotatable parts is the unbalancing value, static-unbalance of said rotatable parts perturbed force F and the moment T to whole star barycenter;

$F={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_j\cos {\mathrm{\β}}_j\\ B_j\sin {\mathrm{\β}}_j\\ 0\end{array}\right],$ $T={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_d\sin {\mathrm{\β}}_d-z_a{B}_j\cos {\mathrm{\β}}_j\\ B_d\cos {\mathrm{\β}}_d+z_a{B}_j\sin {\mathrm{\β}}_j\\ x_a{B}_j\cos {\mathrm{\β}}_j-y_a{B}_j\sin {\mathrm{\β}}_j\end{array}\right]$

Wherein, B _jBe static-unbalance size, B _jBe static-unbalance phase place, B _dBe unbalancing value size, β _dBe unbalancing value phase place, [x _a, y _a, z _a] be that RP is at body series coordinate, ω _rBe the rotatable parts rotating speed.

In the technique scheme, described many-body dynamics model comprises:

Wherein, ω is an angular velocity, v _cBe mass center line speed; η is the mode variable, and Ω is the flexible appendage fundamental vibration frequency, and ξ is a flexible appendage vibration damping coefficient; BR, BT are respectively rotation, the translation coupling coefficient of the relative barycenter of flexible appendage, and F, T are respectively the dynamic and static imbalance of rotatable parts and cause perturbed force and moment.

The invention has the advantages that:

Can reflect real dynamic conditions accurately, the dynamics labile factor of rail control Subsystem Design scheme can be in time found and diagnosed out in the analysis of design time; Analysis in orbit can reappear in rail vibration situation fast and accurately, accurately locatees vibration cause, guarantees normal flight and service operation.

Description of drawings

Accompanying drawing 1 is the process flow diagram of method of the present invention in one embodiment;

Accompanying drawing 2 is a Coupled Dynamics realistic model framework related in the embodiments of the invention.

Embodiment

Below in conjunction with accompanying drawing and embodiment the present invention is further specified.

With reference to figure 1, method of the present invention may further comprise the steps:

Step 1), the characteristic of large-scale rotatable parts is analyzed, set up the kinetic model of said large-scale rotatable parts.

Rotatable parts have generally all carried out balancing when appearing on the scene, but still have remaining static-unbalance and remaining unbalancing value, and described remaining static-unbalance and remaining unbalancing value are the important indicators of examination rotatable parts dynamic performance.The disturbance torque of rotatable parts can be caused by remaining static-unbalance and remaining unbalancing value, therefore, the rotatable parts kinetic model that is used to export disturbance torque can be created by remaining static-unbalance and remaining unbalancing value.Said remaining static-unbalance and unbalancing value generally provide with the form of mould and phase place, in addition, when providing remaining static-unbalance with amount, must confirm reference point locations, generally it are selected in the nominal barycenter place of rotatable parts.The input quantity of the kinetic model that will create as shown in the table:

Table 1

Unbalancing value, static-unbalance can be expressed as respectively the perturbed force F and the moment T of whole star barycenter:

$F={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_j\cos {\mathrm{\β}}_j\\ B_j\sin {\mathrm{\β}}_j\\ 0\end{array}\right],$ $T={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_d\sin {\mathrm{\β}}_d-z_a{B}_j\cos {\mathrm{\β}}_j\\ B_d\cos {\mathrm{\β}}_d+z_a{B}_j\sin {\mathrm{\β}}_j\\ x_a{B}_j\cos {\mathrm{\β}}_j-y_a{B}_j\sin {\mathrm{\β}}_j\end{array}\right]---\left(1\right)$

The kinetic model that the expression formula of above-mentioned perturbed force F and moment T is just set up for said large-scale rotatable parts.

Step 2), to rotatable parts with flexible appendage carry out the Structural Dynamics analysis, through generating the model of vibration that linearizing modal coordinate is described down after the mode truncation, have the many-body dynamics model of flexible appendage in conjunction with the rigid dynamics modelling.

In this step, on classical mechanics theoretical foundation, use D'Alembert's principle and principle of conservation of momentum and derive flexible kinetics equation, be i.e. rigid dynamics model (like first, second equation in the hereinafter formula (2)); The Application of Lagrange's Equations and the principle of virtual work are set up the mathematical model of flexible appendage elastic vibration, i.e. flexible appendage elastic vibration equation (like the 3rd equation in the hereinafter formula (2)).Flexible appendage elastic vibration equation and flexible translation, rotational power equations simultaneousness are obtained flexible dynamics fundamental equation, i.e. many-body dynamics equation.The application constraint modal method is done mode truncation to fundamental equation, asks for approximate solution, and the fundamental equation that obtains under the hybrid coordinate is following:

Wherein, ω is an angular velocity, v _cBe mass center line speed; η is the mode variable, and Ω is the flexible appendage fundamental vibration frequency, and ξ is a flexible appendage vibration damping coefficient; BR, BT are respectively rotation, the translation coupling coefficient of the relative barycenter of flexible appendage, and F, T are respectively the dynamic and static imbalance of rotatable parts and cause perturbed force and moment.

Step 3), in step 1) and step 2) set up Flexible Satellite Attitude dynamics and control system model on the model based set up, utilize this model to carry out emulation.

As shown in Figure 2, described Flexible Satellite Attitude dynamics and control system model comprise rigid dynamics model, flexible appendage model of vibration, rotatable parts moment model and control system model.Wherein, described control system model is used for other models are done FEEDBACK CONTROL, and this model can pass through existing techniques in realizing.

In the simulation process, the rotatable parts moment model generates time dependent perturbed force F and moment T, sends to the rigid dynamics model; The rigid dynamics model comprises translation and rotational power is learned model, and input quantity is the mode variable n of rotatable parts perturbed force F, disturbance torque T and flexible appendage vibration, and output quantity is Eulerian angle Euler, angular velocity omega and mass center line speed v _cThe flexible appendage model of vibration receives angular velocity omega and the mass center line speed v from the rigid dynamics model _c, output modalities coordinate n returns to the rigid dynamics model; That the control system model comprises is definite, control and topworks's model, gathers Eulerian angle Euler and angular velocity omega, with the angular momentum exchanged form to carrying out FEEDBACK CONTROL.

Step 4), the emulated data of said Flexible Satellite Attitude dynamics and control system model is analyzed and assessed.

The resulting emulated data of step 3) (in the rail data) is carried out time and frequency domain analysis, obtain perturbation features.The time-domain analysis fundamental purpose be investigate receive the rotatable parts disturbance after, whether still satisfy index request, draw the rotatable parts disturbance to flexible effect of kinetics degree.Function is analyzed in the fast Fourier transform (FFT) of the main Origin Pro software capable of using of frequency-domain analysis, high pass (High Pass), low pass (Low Pass), band logical (Band Pass), band resistance (Band Block) etc.; Obtain the spectral characteristic of data, be used for the anti-characteristic that pushes away disturbing source and bang path.

Obtain rotatable parts to flexible kinetic effect degree after, those skilled in the art combine existing knowledge, can be according to the design of these information guidings or in the rail fault analysis.

Method of the present invention can be used in rail control and the dynamics Design process design result being verified, also is used in the fault verification and the inverting of rail run duration.

Obviously, those skilled in the art can carry out various changes and distortion to the present invention and not break away from the spirit and scope of the present invention.Like this, if these modifications and distortion belong within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and is out of shape interior.

Claims (3)

1. rotatable parts comprise the simulating analysis of flexible kinetic effect:

Step 1), the characteristic of large-scale rotatable parts is analyzed, set up the kinetic model of said large-scale rotatable parts;

Step 2), to rotatable parts with flexible appendage carry out the Structural Dynamics analysis, through generating the model of vibration that linearizing modal coordinate is described down after the mode truncation, have the many-body dynamics model of flexible appendage in conjunction with the rigid dynamics modelling;

Step 3), in step 1) and step 2) set up Flexible Satellite Attitude dynamics and control system model on the model based set up, utilize this model to carry out emulation;

Step 4), the emulated data that step 3) is obtained are carried out the time-domain and frequency-domain analysis, obtain perturbation features.

2. rotatable parts according to claim 1 are to the simulating analysis of flexible kinetic effect; It is characterized in that; In described step 1), the kinetic model of said large-scale rotatable parts is the unbalancing value, static-unbalance of said rotatable parts perturbed force F and the moment T to whole star barycenter;

$F={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_j\cos {\mathrm{\β}}_j\\ B_j\sin {\mathrm{\β}}_j\\ 0\end{array}\right],$ $T={\mathrm{\ω}}_r^2\left[\begin{array}{c}{B}_d\sin {\mathrm{\β}}_d-z_a{B}_j\cos {\mathrm{\β}}_j\\ B_d\cos {\mathrm{\β}}_d+z_a{B}_j\sin {\mathrm{\β}}_j\\ x_a{B}_j\cos {\mathrm{\β}}_j-y_a{B}_j\sin {\mathrm{\β}}_j\end{array}\right]$

Wherein, B _jBe static-unbalance size, β _jBe static-unbalance phase place, B _dBe unbalancing value size, β _dBe unbalancing value phase place, [x _a, y _a, z _a] be that RP is at body series coordinate, ω _rBe the rotatable parts rotating speed.

3. rotatable parts according to claim 2 is characterized in that to the simulating analysis of flexible kinetic effect described many-body dynamics model comprises:

Wherein, ω is an angular velocity, v _cBe mass center line speed; η is the mode variable, and Ω is the flexible appendage fundamental vibration frequency, and ξ is a flexible appendage vibration damping coefficient; BR, BT are respectively rotation, the translation coupling coefficient of the relative barycenter of flexible appendage, and F, T are respectively the dynamic and static imbalance of rotatable parts and cause perturbed force and moment.

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