A test model quality attribute matching design method considering component motion

Abstract

The application provides a test model mass property matching design method considering component motion, which establishes a test model, a mass center relationship model of fixed components and moving components and a moment of inertia relationship model in component linear motion, calculates the mass, real-time position of the mass center and the moment of inertia relative to the mass center of the moving components based on the model, designs an entity test model based on the obtained mass properties, obtains the actual value, the theoretical value of the combined mass center position and the actual value, the theoretical value of the total moment of inertia of the moving components at the starting position, the ending position and the typical intermediate position based on the entity test model and the theoretical design model respectively, designs the mass properties of the counterweight by analyzing the difference between the actual value and the theoretical value, and realizes real-time simulation of dynamic changes of the mass properties of the entity test model to the theoretical design model in the component motion process. The technical scheme of the application solves the technical problem that the test model is difficult to accurately simulate the dynamic changes of the mass properties of the theoretical design model in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of test model quality attribute matching design, and particularly relates to a test model quality attribute matching design method considering component motion. BACKGROUND

[0002] With the continuous progress of aerospace technology, a new generation of aircraft usually focuses on more flexible flight patterns, which puts forward urgent demand for the research of aircraft deformation technology. When the aircraft deforms dynamically, its attitude angle, angular velocity and linear velocity of components and other parameters change over time, showing nonlinear coupling phenomena of aerodynamics, motion, structure and other disciplines, which brings challenges to the wind tunnel test research of such problems. At present, some wind tunnel test researches on deformable aircraft have been carried out at home and abroad, but the research contents mainly focus on test scheme design, test measurement accuracy, test data processing and other aspects, and the technical difficulties of test model design are less discussed, especially in considering the changes of quality attributes caused by component linear motion.

[0003] Limited by the cross-sectional size of the test section of the wind tunnel, the test model usually needs to be designed with a certain scale reduction, which leads to a significant compression of the structural space of the test model. In the design of the test model, compared with the non-deformable test model, the design of the test model considering the linear motion of the components will be significantly more difficult and complex. In addition to meeting the basic similarity theory of wind tunnel test, it also needs to focus on the dynamic process of the linear motion of the components. The linear motion of the components will directly change the physical quantities such as the center of mass and the moment of inertia of the test model, indirectly affect the change of the attitude angle of the test model in the wind tunnel, and further change its unsteady aerodynamic characteristics. Therefore, in order to truly reflect the kinematic and dynamic response in the dynamic deformation process of the actual aircraft, it is particularly important to simulate the dynamic changes of the quality attributes of the test model. However, considering the complexity of the deformation process, the research on such problems usually needs to be combined with the specific deformation process of the components to carry out targeted analysis. Based on this, the present application carries out related research on the dynamic changes of the quality attributes of the test model under the linear motion of the components, and provides a test model quality attribute matching design and analysis method under the linear motion of the components. SUMMARY

[0004] The present application provides a test model quality attribute matching design method considering component motion, which can solve the technical problem that the test model in the prior art cannot accurately simulate the dynamic changes of the quality attributes of the theoretical design model.

[0005] According to an aspect of the present application, a test model quality attribute matching design method considering component motion is provided, the test model comprising a fixed component as a test model body structure and a moving component arranged on the fixed component, the moving component moving along the interface with the fixed component, the method comprising:

[0006] Based on the rigid body kinematics relationship and the parallel axis theorem, a first mass center relationship model and a first moment of inertia relationship model of the theoretical design model, the fixed component and the moving component are established;

[0007] The total mass (m'+m) of the theoretical design model, the real-time position (x G (t),y G (t),z G (t)) of the combined mass center of the theoretical design model, the real-time values (J xG (t),J yG (t),J zG (t)) of the total moment of inertia of the theoretical design model, the mass m' of the fixed component, the position (x',y',z') of the mass center of the fixed component and the moments of inertia (J x ',J y ',J z ') of the fixed component relative to the mass center thereof are acquired, and the mass m of the moving component is calculated according to the total mass (m'+m) of the theoretical design model and the mass m' of the fixed component;

[0008] Based on the first mass center relationship model, the real-time position (x(t),y(t),z(t)) of the mass center of the moving component is calculated according to the real-time position (x G (t),y G (t),z G (t)) of the combined mass center of the theoretical design model, the total mass (m'+m) of the theoretical design model, the mass m' of the fixed component, the position (x',y',z') of the mass center of the fixed component and the mass m of the moving component;

[0009] Based on the first moment of inertia relationship model, the moments of inertia (J xG (0),J yG (0),J zG (0)) of the moving component relative to the mass center thereof are calculated according to the total mass (m'+m) of the theoretical design model, the real-time values (J x (t),J y (t),J z (t)) of the total moment of inertia of the theoretical design model, the mass m' of the fixed component, the position (x',y',z') of the mass center of the fixed component, the moments of inertia (J x ',J y ',J z ') of the fixed component relative to the mass center thereof, the mass m of the moving component and the real-time position (x(t),y(t),z(t)) of the mass center of the moving component;

[0010] based on the calculated real-time position (x(t), y(t), z(t)) of the mass center of the moving part and the moment of inertia (J x (0), J y (0), J z (0)) of the moving part relative to its mass center, a designed entity moving part is obtained, and the designed entity moving part is installed on the designed entity fixed part to obtain an entity test model;

[0011] a second mass center relationship model and a second moment of inertia relationship model are established among the counterweight, the theoretically designed model and the entity test model;

[0012] the actual value of the mass center position and the actual value of the total moment of inertia of the moving part in the entity test model at the start position, the end position and the intermediate position of the movement are measured respectively, and based on the real-time position (x G (t), y G (t), z G (t)) of the mass center of the theoretically designed model and the real-time value (J xG (t), J yG (t), J zG (t)) of the total moment of inertia of the theoretically designed model, the theoretical value of the mass center position and the theoretical value of the total moment of inertia when the moving part is at the start position, the end position and the intermediate position of the movement are calculated respectively;

[0013] the actual value of the mass center position and the theoretical value of the mass center position at the start position, the end position and the intermediate position of the movement are compared, and the mass center position (x p , y p , z p ) of the counterweight is determined according to the structure space of the entity test model;

[0014] based on the second mass center relationship model and the determined mass center position (x p , y p , z p ) of the counterweight, the mass m p of the counterweight is calculated;

[0015] based on the second moment of inertia relationship model and the mass m p of the counterweight, the moment of inertia (J xp , J yp , J zp ) of the counterweight relative to its mass center is calculated.

[0016] Further, the first mass center relationship model of the theoretically designed model, the fixed part and the moving part is:

[0017] x G (t) = [m'x' + m x(t)] / (m' + m),

[0018] y G (t) = [m'y' + m y(t)] / (m' + m),

[0019] z G (t) = [m'z' + m z(t)] / (m' + m),

[0020] Further, the first moment of inertia relationship model of the three of the theoretical design model, the fixed component and the moving component is:

[0021] J xG (t) = J x (0) + J' x + [m'm / (m' + m)] d 2 ,

[0022] J yG (t) = J y (0) + J' y + [m'm / (m' + m)] d 2 ,

[0023] J zG (t) = J z (0) + J' z + [m'm / (m' + m)] d 2 ,

[0024] d 2 = [x(t) - x'] 2 + [y(t) - y'] 2 + [z(t) - z'] 2 ,

[0025] In the above formula, d 2 represents the square of the distance from the center of mass of the moving component to the center of mass of the fixed component.

[0026] Further, the second center of mass relationship model between the three of the counterweight, the theoretical design model and the entity test model is:

[0027] m p = (m' + m) [x" G (t) - x G (t)] / [x G (t) - x p ],

[0028] m p = (m' + m) [y" G (t) - y G(t)] / [y G (t)-y p ],

[0029] m p =(m'+m)[z G (t)-z G (t)] / [z G (t)-z p ],

[0030] Further, the second moment of inertia relationship model between the counterweight, the theoretical design model and the physical test model is:

[0031] J xG (t)=J xG (t)+(m'+m){[x G (t)-x G (t)] 2 +[y G (t)-y G (t)] 2 +[z G (t)-

[0032] z G (t)] 2}+J xp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2},

[0033] J yG (t)=J yG (t)+(m'+m){[x G (t)-x G (t)] 2 +[y G (t)-y G (t)] 2 +[z G (t)-

[0034] z G (t)] 2}+J yp +m p {[x G (t)-x p ] 2 +[y G(t) - x p 2 (t) - y G p 2

[0035] (t) - z zG zG G G 2 G G 2 G

[0036] G 2 zp p G p 2 G p 2 G p 2

[0037] x G y G z G G G G

[0038] ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​The technical scheme of the application provides a test model mass property matching design method considering component motion, which is based on rigid body kinematics relation and parallel axis theorem, and establishes a center of mass relation model and a moment of inertia relation model of the test model, a fixed component and a moving component in component linear motion, calculates the real-time position of the center of mass of the moving component and the moment of inertia of the moving component relative to the center of mass of the moving component based on the model, designs an entity test model based on the mass properties of the moving component obtained in the foregoing, measures the actual values of the combined center of mass position and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position based on the entity test model, then establishes a center of mass relation model and a moment of inertia relation model among the counterweight, the theoretically designed model and the entity test model, obtains the theoretical values of the combined center of mass position and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position based on the model, and designs the mass properties of the counterweight to be added or deleted by analyzing the differences of the combined center of mass and the moment of inertia between the test model in the theoretical state and the actual state, realizes real-time simulation of dynamic changes of the mass properties of the entity test model to the theoretically designed model in the component motion process, and can be used to guide the test model design of a deformable aircraft. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is readily understood that the drawings are merely illustrative of some embodiments of the application and therefore should not be taken to limit the scope of the application, as described herein, as the scope of the application is defined solely by the appended claims.

[0040] Figure 1 Fig. 1 shows a center of mass change principle diagram of test model component linear motion according to a specific embodiment of the application;

[0041] Figure 2 Fig. 3 shows a principle diagram of adding a counterweight to change the mass properties of a test model according to a specific embodiment of the application. DETAILED DESCRIPTION

[0042] It should be noted that the embodiments described in this application and characteristics in the embodiments can be combined with each other in the case of no conflict. The technical solutions in the embodiments will be described clearly and completely in combination with the drawings of the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the application and use of the application or the application and use of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0043] It should be noted that the terms used herein are only intended to describe specific embodiments, and are not intended to limit the exemplary embodiments according to the application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, there is a feature, step, operation, device, component and / or combination thereof.

[0044] Unless specifically stated otherwise, the relative arrangement of the components and steps illustrated in these embodiments do not limit the scope of the application. At the same time, it should be understood that the size of each part shown in the drawings is not drawn in accordance with the actual proportion relationship. The technology, methods and devices known to those skilled in the art can not be discussed in detail, but in appropriate cases, the technology, methods and devices should be considered as part of the authorized description. In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, and not as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0045] The purpose of the present application is to provide a quality attribute matching design and analysis method of a wind tunnel test model in a component linear motion process. The method closely surrounds the development needs of the deformation capability of a new generation of aircraft, focuses on the test model design difficulties of the dynamic deformation process, focuses on the quality attribute changes of the model center of mass, moment of inertia and other problems caused by component deformation, and gives relevant solutions. It should be noted that the deformation process described in the present application is the deformation of rigid body components, and the deformation technology involved is structural motion deformation, which is a simple linear displacement process. In order to facilitate discussion, the present application uses a simplified test model composed of a moving component and a fixed component to carry out method research, wherein the moving component is located above the fixed component and can move along the interface between the two. During the linear motion of the component, the combined center of mass and total moment of inertia of the test model will change in real time. For a specific test model, the fixed component can be regarded as the body structure of the test model, and the moving component can be regarded as the linear motion structure of the model.

[0046] In the design of the test model, the body structure (fixed component) design of the test model usually needs to be carried out under the constraints of meeting the size envelope, structural strength, structural weight and the like. After the above design is completed, the envelope of the structural space size is basically determined, and the design of the moving component under the above space usually has certain difficulty, which puts forward potential constraint conditions for the design of the mass, real-time position of the center of mass and the moment of inertia of the moving component. In addition, after the designed test model is processed, there is usually a certain deviation between the measured value and the designed value of the quality attribute of the model, and the influence of this deviation is similar to that caused by the component slip motion, which will also affect the kinematics and dynamics characteristics of the model, and further change the stress characteristics of the test model. In view of this problem, the present application adopts the method of adding or deleting counterweight blocks to match the quality attribute of the processed test model.

[0047] The present application will mainly focus on the above two technical difficulties, and through dimensional analysis, rigid body planar kinematics relationship, parallel axis theorem and other analysis means, the research and discussion are carried out from the theoretical level, and a test model quality attribute matching design and analysis method under the linear motion of the component is given, which provides technical reference for relevant personnel to carry out test model design of deformation aircraft.

[0048] Specifically, according to the specific embodiment of the present application, a test model quality attribute matching design method considering component motion is provided, the test model includes a fixed component as a body structure of the test model and a moving component arranged on the fixed component, the moving component moves along the interface with the fixed component, and the method includes:

[0049] Based on the rigid body kinematics relationship and the parallel axis theorem, a first center of mass relationship model and a first moment of inertia relationship model of the three of the theoretical design model, the fixed component and the moving component are established;

[0050] Obtain the total mass (m'+m) of the theoretical design model and the real-time position (x) of the center of mass of the theoretical design model. G (t),y G (t),z G (t)), Real-time value of total rotational inertia of theoretical design model (J) xG (t),J yG (t),J zG (t)), the mass m′ of the fixed component, the position of the center of mass of the fixed component (x′, y′, z′), and the moment of inertia of the fixed component relative to its own center of mass (J). x ′,J y ′,J z The mass m of the moving part is calculated based on the total mass (m'+m) of the theoretical design model and the mass m′ of the fixed part.

[0051] Based on the first centroid relation model, the real-time position of the resultant centroid (x) of the theoretically designed model is... G (t),y G (t),z G The real-time position (x(t), y(t), z(t)) of the center of mass of the moving part is calculated from the total mass (m'+m) of the theoretical design model, the mass m′ of the fixed part, the position (x′, y′, z′) of the center of mass of the fixed part, and the mass m of the moving part.

[0052] Based on the first rotational inertia relationship model, the total mass (m'+m) of the theoretically designed model and the real-time value of the total rotational inertia of the theoretically designed model (J) are used. xG (t),J yG (t),J zG (t)), mass m′ of the fixed component, position of the center of mass of the fixed component (x′, y′, z′), and moment of inertia of the fixed component relative to its own center of mass (J). x ′,J y ′,J z The moment of inertia (J) of the moving part relative to its own center of mass is calculated using the mass m of the moving part and the real-time position (x(t), y(t), z(t)) of the moving part. x (0),J y (0),J z (0));

[0053] Based on the calculated real-time position (x(t), y(t), z(t)) of the center of mass of the moving part and the moment of inertia (J) of the moving part relative to its own center of mass... x (0),J y (0),J zdesigning a physical moving component, mounting the designed physical moving component on the designed physical fixed component to obtain a physical test model;

[0054] establishing a second center-of-mass relationship model and a second moment-of-inertia relationship model among the counterweight, the theoretically designed model and the physical test model;

[0055] measuring actual values of the center-of-mass position and the total moment-of-inertia of the physical test model when the moving component is located at the start position, the end position and the intermediate position of movement respectively, and calculating theoretical values of the center-of-mass position and the total moment-of-inertia of the physical test model based on real-time positions (x G (t),y G (t),z G (t)) of the center-of-mass of the theoretically designed model and real-time values (J xG (t),J yG (t),J zG (t)) of the total moment-of-inertia of the theoretically designed model respectively;

[0056] determining the center-of-mass position (x p ,y p ,z p ) of the counterweight according to differences between the actual values and the theoretical values of the center-of-mass position corresponding to the start position, the end position and the intermediate position of movement respectively and the structure space of the physical test model;

[0057] calculating the mass m p of the counterweight based on the second center-of-mass relationship model and the determined center-of-mass position (x p ,y p ,z p ) of the counterweight;

[0058] calculating the moments of inertia (J p ,J xp ,J yp ) of the counterweight relative to its center-of-mass based on the second moment-of-inertia relationship model and the mass m zp .

[0059] With the configuration, a test model quality attribute matching design method considering component motion is provided, which is based on rigid body kinematics and parallel axis theorem, and a center of mass relationship model and a moment of inertia relationship model of the test model, the fixed component and the moving component in linear motion of the component are established, and real-time position of the center of mass of the moving component and moment of inertia of the moving component relative to the center of mass of the moving component are calculated based on the model; the entity test model is designed based on the obtained quality attributes of the moving component, and actual values of the combined center of mass and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position are measured based on the entity test model; then, a center of mass relationship model and a moment of inertia relationship model among the counterweight, the theoretically designed model and the entity test model are established, and theoretical values of the combined center of mass and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position are obtained based on the model; by analyzing the differences of the combined center of mass and the moment of inertia between the test model in the theoretical state and the actual state, the quality attributes of the counterweight to be added or deleted are designed, the real-time simulation of the dynamic change of the quality attributes of the entity test model to the theoretically designed model in the process of component motion is realized, and the test model design of the morphing aircraft can be guided. Compared with the prior art, the technical scheme of the present application can solve the technical problem that the test model is difficult to accurately simulate the dynamic change of the quality attributes of the theoretically designed model in the prior art.

[0060] Based on the above embodiment, the derivation and establishment process of the first center of mass relationship model, the first moment of inertia relationship model, the second center of mass relationship model and the second moment of inertia relationship model in the embodiment of the present application is as follows:

[0061] Please refer to Figure 1 , where t represents time, x, y and z represent three coordinates of the center of mass; subscripts 1 and 2 correspond to state 1 and state 2 respectively; subscript G represents the combined center of mass of the test model; u(t) and v(t) respectively correspond to the moving speed of the combined center of mass of the test model and the center of mass of the moving component itself. When the moving component of the test model moves from state 1 (t1, x1, y1, z1) to state 2 (t2, x2, y2, z2) at a speed of v(t), the combined center of mass of the test model will change from (t1, x G1 ,y G1 ,z G1 ) to (t2, x G2 ,y G2 ,z G2 ) at a speed of u(t). Through mathematical analysis, the kinematic relationship between the linear displacement of the center of mass of the moving component and the linear displacement of the combined center of mass of the test model can be established. Assuming that at any time t, the mass of the fixed component of the test model is m', and the center of mass (x', y', z') of the fixed component is independent of time t; the mass of the moving component is m, and the center of mass (x(t), y(t), z(t)) of the moving component, then:

[0062] Total structural mass:

[0063] M = m' + m (1)

[0064] The centroid of the model:

[0065]

[0066] From t1 to t2, the distance the center of mass of the moving part moves is:

[0067]

[0068] The relationship between the distances the centroid of the experimental model moved is as follows:

[0069]

[0070] It can be seen that the distance ΔS that the center of mass of the test model moves is the product of the distance Δs that the moving part moves and the proportionality coefficient m / (m'+m), which represents the ratio of the mass of the moving part to the total mass of the test model. Similarly, the ratio of the change distance of the three coordinates of the center of mass of the test model to the change distance of the three coordinates of the center of mass of the moving part both satisfy the above proportionality coefficient.

[0071] Formula (2) is the first centroid relationship model constructed based on the theoretical design model, fixed parts and moving parts.

[0072] After obtaining the aforementioned relationship between the coordinates of the center of mass and the displacement, this invention focuses on the change in the moment of inertia during this process. Let the moment of inertia of the fixed component relative to its own center of mass (x', y', z') be (J'). x ,J' y ,J' z The moment of inertia of the moving part remains unchanged throughout the deformation process. For the moving part, from time t1 to time t2, neglecting the shape change of the moving part itself (considering it as a rigid body) and assuming the mass distribution of the moving part remains constant, then the moment of inertia of the moving part relative to its center of mass is equal at different times, i.e.: J x (t)=J x (0), J y (t)=J y (0), J z (t)=J z (0).

[0073] For any time t, according to the parallel axis theorem, the x-axis rotational inertia generated by the moving parts and the stationary parts around the net mass center of the test model are, in order:

[0074] J xG_1 (t)=J x (0)+m{[x G(t) = J 2 + [m' d G (t) = -J 2 + [m' d G (t) = -J 2} (4)

[0075] J xG_2 (t) = J x + m' d 2 (t) = -J x + [m' d G (t) = -J 2 + [m' d G (t) = -J 2 + [m' d G (t) = -J 2} (5)

[0076] Summing and simplifying, the total moment of inertia about the center of mass of the test model in the x direction at time t is:

[0077] J xG (t) = J xG_1 (0) + J xG_2 (t)

[0078] = J x (0) + J x + [m' m / (m' + m)] · d 2 (6)

[0079] where,

[0080] d 2 = [x(t) - x'] 2 + [y(t) - y'] 2 + [z(t) - z'] 2 (7)

[0081] represents the square of the distance from the center of mass of the moving part to the center of mass of the fixed part. The steps for solving the moments of inertia in the y and z directions are consistent, and the specific expressions are as follows:

[0082] J yG (t) = J y (0) + J y + [m' m / (m' + m)] · d 2 (8)

[0083] J zG (t) = J z (0) + J z + [m' m / (m' + m)] · d 2 (9)

[0084] Wherein, the expression (4), (6), (8), (9) describes the test model dynamic deformation process of moving parts itself and the entire test model in the mass center moving distance and the conversion relationship of the moment of inertia. Expression (6), (7), (8), (9) constitutes the first moment of inertia relationship model based on the theoretical design model, the fixed parts and the moving parts of the three.

[0085] For wind tunnel test, the size envelope of the test model will be limited by the size of the selected test section of the wind tunnel, and usually needs to be scaled down on the basis of the original shape. Based on the dimensional analysis theory, it is not difficult to obtain that the test model and the real aircraft need to meet the following proportional relationship in total mass, combined mass center and total moment of inertia:

[0086] M 风洞 / M 飞行 =K ρb ×K l 3

[0087] x G风洞 / x G飞行 =y G风洞 / y G飞行 =z G风洞 / z G飞行 =K l (10)

[0088] J 风洞 / J 飞行 =K ρ K l 5

[0089] Wherein K ρb represent the average mass density ratio of the test model and the real aircraft, K l represent the size ratio of the test model and the real aircraft, K ρ represent the ratio of the flow density under the wind tunnel state and the flight state. It can be seen that when the wind tunnel is selected, the model scaling ratio K l is determined, and under the assumption that K ρb is consistent, the total mass, combined mass center and total moment of inertia of the wind tunnel test model can be uniquely determined by expression (10). At this time, M 风洞 , (x G风洞 , y G风洞 , z G风洞 ), J 风洞 are (m'+m), (x G (t), y G (t), z G (t)), (J xG (t), J yG(t),J zG (t)).

[0090] For a given test model, after the basic design of the main structure of the test model is completed, in order to realize the real-time simulation of the moment of inertia and center of mass during motion, it is usually necessary to design the moving parts independently. Without considering other factors, the known physical quantities at this point include: the total mass of the test model (m'+m), the real-time position of the resultant center of mass (x...). G (t),y G (t),z G (t) and the real-time value of the total moment of inertia (J) xG (t),J yG (t),J zG (t)), the mass m' of the fixed component (the main structure of the test model), its own center of mass (x', y', z'), and its moment of inertia (J') relative to its own center of mass. x ,J' y ,J' z At this point, the mass m of the moving part is uniquely determined by the total mass of the model and the mass of the fixed part. Therefore, the proportionality constant m / (m'+m) is a known term, and the real-time position (x(t), y(t), z(t)) of the center of mass of the moving part can be obtained from expression (2). Substituting the obtained results into equations (6), (7), (8), and (9), the moment of inertia (J) of the moving part can be solved. x (0),J y (0),J z (0)). At this point, all mass attribute parameters of the moving parts are known quantities, and the independent design of the moving parts can be carried out based on the above parameter values ​​and the structural space of the experimental model.

[0091] Furthermore, the above derivation process only applies to theoretical cases. In reality, various constraints often exist during the design of experimental models, leading to certain deviations in the total moment of inertia or the position of the net center of mass obtained after the model is manufactured. These deviations may be caused by manufacturing accuracy or by differences between some finished devices inside the model and the actual aircraft. To address this problem, this invention uses the method of adding or removing counterweights during the model's actual testing to match the mass attributes. In this case, the constraints on the mass simulation in expression (10) are appropriately relaxed.

[0092] This invention is illustrated by adding counterweights, as shown in the embodiments below. Figure 2 As shown, m p x represents the mass of the counterweight. p y p z p The three coordinates representing the center of mass of the counterweight are J and J respectively. xp Jyp , J zp , J G , J G , J G , J xG , J yG , J zG , J G , J G , J G , J xG , J yG , J zG , J p , J p , J p , J p , J p , J p , J p , J

[0093] m p = (m' + m) [x G (t) - x G (t)] / [x G (t) - x p ]

[0094] m p = (m' + m) [y G (t) - y G (t)] / [y G (t) - y p ] (11)

[0095] m p = (m' + m) [z G (t) - z G (t)] / [z G (t) - z p ],

[0096] The inertia moment of the weight block and the model in the actual state is converted to the theoretical state, taking the inertia moment of x direction as an example, that is:

[0097] JxG (t)=J” xG (t)+(m'+m){[x G (t)-x” G (t)] 2 +[y G (t)-y” G (t)] 2 +[z G (t)-

[0098] z” G (t)] 2}+J xp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2}(12)

[0099] The moment of inertia J of the counterweight can be obtained from expression (12). xp Similarly, J can be obtained using the following formula. yp J zp :

[0100] J yG (t)=J” yG (t)+(m'+m){[x G (t)-x” G (t)] 2 +[y G (t)-y” G (t)] 2 +[z G (t)-

[0101] z” G (t)] 2}+J yp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2}(13)

[0102] J zG (t)=J” zG(t) + (m' + m){[x G (t) - x G (t)] 2 +[y G (t) - y G (t)] 2 +[z G (t) - z

[0103] z G (t)] 2}+J zp +m p {[x G (t) - x p ] 2 +[y G (t) - y p ] 2 +[z G (t) - z p ] 2}(14)

[0104] In the above formula, (J x ″ G (t), J y ″ G (t), J z ″ G (t)) represents the real-time value of the total moment of inertia of the entity test model, (x' G '(t), y' G '(t), z' G '(t)) represents the real-time position of the mass center of the entity test model.

[0105] The three expressions of formula (11) are the second mass center relationship model constructed based on the counterweight, the theoretical design model and the entity test model, and formula (12), (13) and (14) are the second moment of inertia relationship model constructed based on the counterweight, the theoretical design model and the entity test model. As can be seen from formula (11)-(14), the mass and moment of inertia of the counterweight are also functions of t, which indicates that, for the test model involving the deformation motion of the component, to eliminate the above error, the counterweight needs to be loaded into the test model in a new motion form. Obviously, this is not desirable. In the process of adjusting the mass properties of the test model, the position of the counterweight is usually fixed. Based on this, in the embodiment of the application, the difference of the mass properties at the boundary positions before and after the motion and the typical intermediate positions is analyzed, the optimal mass center position of the counterweight is determined by preferentially combining the mass center difference and the structure space, the mass of the counterweight is determined, and then the reasonable moment of inertia of the counterweight is designed by analyzing the difference of the moment of inertia at the motion boundaries and combining formula (12), (13) and (14).

[0106] The scheme of deleting the counterweight in the present application is similar to the scheme of adding the counterweight, and will not be described here again.

[0107] Overall, the test model mass property matching design method considering component motion provided by the present application includes the following two main aspects:

[0108] (1) Based on the rigid body kinematics relationship and the parallel axis theorem, the real-time changes of the combined mass center and the total moment of inertia of the test model during the motion of the moving component along the interface line of the fixed component are analyzed, and the constraint conditions that the mass center and the moment of inertia of the moving component itself need to meet are given based on the dimensional analysis theory.

[0109] (2) Based on the rigid body kinematics relationship and the parallel axis theorem, the deviation between the design value and the measured value of the mass property of the model is analyzed. From the differences in the mass center and the moment of inertia between the theoretical state and the actual state, the mass center position and the moment of inertia of the added counterweight are analyzed.

[0110] In summary, the present application provides a test model mass property matching design method considering component motion. The method is based on the rigid body kinematics relationship and the parallel axis theorem, and establishes the mass center relationship model and the moment of inertia relationship model of the test model, the fixed component and the moving component during the linear motion of the component. The real-time position of the mass center of the moving component and the moment of inertia of the moving component relative to its mass center are calculated based on the model. The entity test model is obtained based on the mass properties of the moving component obtained as described above. The actual values of the combined mass center position and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position are measured based on the entity test model. Then, the mass center relationship model and the moment of inertia relationship model among the counterweight, the theoretical design model and the entity test model are established, and the theoretical values of the combined mass center position and the total moment of inertia of the moving component at the starting position, the ending position and the typical intermediate position are obtained based on the model. By analyzing the differences in the combined mass center and the moment of inertia between the theoretical state and the actual state of the test model, the mass properties of the counterweight that need to be added or deleted are designed, the real-time simulation of the dynamic changes of the mass properties of the entity test model to the theoretical design model during the motion of the component is realized, and the test model design of the morphing aircraft can be guided. Compared with the prior art, the technical scheme of the present application can solve the technical problem that the test model in the prior art is difficult to accurately simulate the dynamic changes of the mass properties of the theoretical design model.

[0111] For purposes of the description hereinafter, spatial or directional terms, for example, "above", "below", "upper", "lower", and the like, can be used, and relate to the device as illustrated in the figures. However, it is to be understood that no absolute or relative orientation of the device is intended or implied, unless specifically described as such. Terms concerning attachments, coupling and the like, such as "connected" and "coupled" and the like, are to be construed in accordance with their normal meanings, that is, as referring to an indirect or direct connection or coupling. Any reference to "comprising" or "containing" is to be construed as meaning "comprising or containing, but not limited to". Any reference to "comprising" or "containing" is to be construed as meaning "comprising or containing, but not limited to".

[0112] In addition, it should be pointed out that the use of the terms "first", "second" and the like, to describe various elements in the claims, is merely intended to distinguish between two steps or entities of the application, and is not intended to limit the scope of the present application, unless specifically stated otherwise. Thus, the terms "first", "second", and the like, are not intended to limit the scope of the present application, unless specifically stated otherwise.

[0113] The preferred embodiments herein disclosed are not intended to limit the scope of the application, but rather the application is to cover all modifications and alternatives within the scope and spirit of the application. Therefore, the above description should not be construed as limiting, but merely as illustrative of the present application.

Claims

1. A test model quality attribute matching design method considering component motion, characterized by, The test model comprises a fixed component as a test model body structure and a moving component arranged on the fixed component, the moving component making translational motion along an interface with the fixed component, and the method comprises: Based on the rigid body kinematics relationship and the parallel axis theorem, a first center of mass relationship model and a first moment of inertia relationship model of the theoretical design model, the fixed component and the moving component are established; acquire total mass (m' + m) of the theoretical design model, real-time position (x G (t), y G (t), z G (t)) of the mass center of the theoretical design model, real-time values (J xG (t), J yG (t), J zG (t)) of the total moment of inertia of the theoretical design model, mass m' of the fixed component, mass center position (x', y', z') of the fixed component, and moments of inertia (J x ', J y ', J z ') of the fixed component relative to its mass center, and calculate the mass m of the moving component according to the total mass (m' + m) of the theoretical design model and the mass m' of the fixed component; calculating the real-time position (x(t),y(t),z(t)) of the mass center of the moving part based on the first mass center relation model according to the combined mass center real-time position (x G (t),y G (t),z G (t)) of the theoretical design model, the total mass (m'+m) of the theoretical design model, the mass m' of the fixed part, the mass center position (x',y',z') of the fixed part, and the mass m of the moving part; based on the first moment of inertia relationship model according to the total mass (m' + m) of the theoretical design model, the real-time value of the total moment of inertia (J xG (t), J yG (t), J zG (t)), the fixed component mass m', the fixed component mass center position (x', y', z'), the moment of inertia (J x ', J y ', J z ') of the fixed component relative to its own mass center, the moving component mass m, and the real-time position (x(t), y(t), z(t)) of the moving component mass center, the moment of inertia (J x (0), J y (0), J z (0)) of the moving component relative to its own mass center is calculated. based on the calculated real-time position (x(t), y(t), z(t)) of the mass center of the moving component and the moment of inertia (J x (0), J y (0), J z (0)) of the moving component relative to its mass center, a physical moving component is designed, and the designed physical moving component is installed on the designed physical fixed component to obtain a physical test model; A second center of mass relationship model and a second moment of inertia relationship model among the counterweight, the theoretical design model and the entity test model are established; measuring actual values of the center-of-mass position and the total moment of inertia of the moving part in the entity test model when the moving part is located at the start position, the end position and the intermediate position of movement, respectively, and calculating theoretical values of the center-of-mass position and the total moment of inertia of the moving part when the moving part is located at the start position, the end position and the intermediate position of movement, respectively, based on real-time values of the center-of-mass position (x G (t),y G (t),z G (t)) of the entity test model and real-time values of the total moment of inertia (J xG (t),J yG (t),J zG (t)) of the theoretical design model; and According to the difference between the actual value of the center-of-mass position corresponding to the starting position of the movement and the theoretical value of the center-of-mass position, the difference between the actual value of the center-of-mass position corresponding to the ending position of the movement and the theoretical value of the center-of-mass position, the difference between the actual value of the center-of-mass position corresponding to the intermediate position of the movement and the theoretical value of the center-of-mass position, and the structural space of the entity test model, the center-of-mass position (x p ,y p ,z p ) of the counterweight is determined. calculating a mass m p of the counterweight based on the second center of mass relationship model and the determined counterweight center of mass position (x p ,y p ,z p ); based on the second moment of inertia relationship model and the mass m p The moment of inertia of the counterweight relative to its own center of mass (J xp ,J yp ,J zp ) is calculated.

2. The method of claim 1, wherein, The first center of mass relationship model of the theoretical design model, the fixed component and the moving component is: x G (t) = [m'x' + m x(t)] / (m' + m), y G (t) = [m'y' + m - y(t)] / (m' + m), z G (t) = [m'z' + m - z(t)] / (m' + m).

3. The method of claim 2, wherein, The first moment of inertia relationship model of the theoretical design model, the fixed component and the moving component is: J xG (t) = J x (0) + J' x + [m'm / (m'+m)]·d 2 , J yG (t) = J y (0) + J' y + [m'm / (m'+m)]·d 2 , J zG (t) = J z (0) + J' z + [m'm / (m'+m)]·d 2 , d 2 = [x(t) - x'] 2 + [y(t) - y'] 2 + [z(t) - z'] 2 , In the above equation, d 2 represents the square of the distance from the center of mass of the moving part to the center of mass of the fixed part.

4. The method of claim 3, wherein, The second center of mass relationship model among the counterweight, the theoretical design model and the entity test model is: m p = (m' + m)[x G (t) - x G (t)] / [x G (t) - x p ], m p = (m' + m)[y G (t) - y G (t)] / [y G (t) - y p ], m p = (m' + m)[z G (t) - z G (t)] / [z G (t) - z p ].

5. The method of claim 4, wherein, The second moment of inertia relationship model among the counterweight, the theoretical design model and the entity test model is: J xG (t) = J xG (t) + (m' + m){[x G (t) - x G (t)] 2 + [y G (t) - y G (t)] 2 + [z G (t) - z G (t) 2}+J xp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2} J yG (t) = J yG (t) + (m' + m){[x G (t) - x G (t)] 2 + [y G (t) - y G (t)] 2 + [z G (t) - z G (t) 2}+J yp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2} J zG (t) = J zG (t) + (m' + m){[x G (t) - x G (t)] 2 + [y G (t) - y G (t)] 2 + [z G (t) - z G (t) 2}+J zp +m p {[x G (t)-x p ] 2 +[y G (t)-y p ] 2 +[z G (t)-z p ] 2} In the above equation, (J x In the above equation, (J G In the above equation, (J y In the above equation, (J G In the above equation, (J z In the above equation, (J G In the above equation, (J G In the above equation, (J G In the above equation, (J G In the above equation, (J

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