CN112977875B - Multi-section constraint sequence optimization method for assembly gap of wing box - Google Patents
Multi-section constraint sequence optimization method for assembly gap of wing box Download PDFInfo
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Abstract
The invention discloses a method for optimizing a multi-section constraint sequence of assembly gaps of a wing box of an aircraft, which eliminates the assembly gaps which are generated in the step-by-step assembly process of a typical aircraft major component, namely the wing box of the aircraft and exist between a wing wallboard and a framework by designing a device for controlling the assembly gaps of the wing box based on inflation and compression of a segmented air bag, and ensures that the local area of the wallboard is not easy to deform or generate wrinkles by optimizing the multi-section constraint action sequence.
Description
Technical Field
The invention relates to the technical field of digital assembly and manufacturing, in particular to a method for optimizing a multi-section constraint sequence of assembly gaps of a wing box.
Background
In the assembly and manufacturing stage of a typical airplane large component 'wing box', error sources such as component manufacturing errors and assembly deformation are continuously transmitted and accumulated in the step-by-step assembly process of the wing box, so that an assembly gap exists between a wing wall plate and a framework. After the wing wall plate and the framework are adjusted and aligned, an automatic hole making device is needed to process a pre-connecting hole and install a pre-connecting piece such as a piercing clamp or a bolt. However, the existence of the wing box assembly gap may cause that burrs enter the gap to scratch a product when the pre-connecting hole is manufactured, the position of the wall plate is difficult to align with the pre-connecting hole on the framework when the wall plate is disassembled and reset, and the wing box part bulges after pre-connection and the like. In order to solve the problem, the assembly clearance control device based on the inflation and compression of the segmented air bags can be eliminated, but the improper multi-section constraint action sequence can cause the deformation of local areas of the wall plate to be poor and even cause wrinkles.
Disclosure of Invention
The invention aims to solve the technical problem of providing a device for controlling the assembly clearance of a wing box of an aircraft and a method for optimizing a multi-section constraint sequence.
In a first aspect, the invention provides a wing box assembly gap control device, which comprises at least two gap control units, wherein each gap control unit comprises a front beam support, a back beam support, a wall plate pressing main body and a plurality of segmented airbags;
one end of the front beam support is connected with the front beam positioning tool, one end of the back beam support is connected with the back beam positioning tool, two ends of the wallboard pressing main body are fixedly connected with the other ends of the front beam support and the back beam support respectively, the segmented airbags are fixedly arranged on the inner side of the arc of the wallboard pressing main body in sequence, the wallboard pressing main body is arranged on the outer side of the wallboard through the segmented airbags in a pressing mode, and the wallboard is pressed to eliminate assembly gaps after the segmented airbags inflate.
Further, the front beam support and the back beam support can move within a set distance in the thickness direction of the wing box and are used for adjusting the distance between the wall plate pressing main body and the wall plate.
Furthermore, the wallboard pressing main body is an arc-shaped pressing strip, and the radian of the arc-shaped pressing strip is consistent with that of the appearance of the wallboard.
In a second aspect, the present invention provides a method for optimizing a multi-section constraint sequence of an assembly gap of a wing box, which needs to provide the apparatus of the first aspect, the method includes:
step 10, setting m assembly gap observation points at preset intervals on a connecting line of a wing box wall plate and a framework of the wing, setting n assembly deformation observation points at preset intervals on the wing box, and then constructing an optimization objective function G obj Minimizing the optimization objective function by adopting an ant colony optimization algorithm,
wherein gap (j) is the assembly gap at the jth assembly gap observation point, and j is equal to [1, m ]]Def (i) is the ith assembly variationAssembly distortion at observation point, i ∈ [1, n ]]Phi and phi are weight coefficients, v, set to balance the effect of assembly gap and assembly distortion on the optimization process j Weight, ω, for the jth set-up gap observation point i Weights for the ith assembly distortion observation point;
step 20, in finite element analysis software, establishing a multi-section constraint finite element analysis model for compressing the segmented airbags according to the wing box assembly gap control device, and presetting N linear loads at N segmented airbags for applying the compression force of the segmented airbags;
step 30, designing a fitness function F according to the objective function obj Taking the inverse of the objective function as the fitness function, i.e. F obj ＝1/G obj Randomly generating a multi-section constraint action sequence for ant colony algorithm variable initialization, calling finite element analysis software, carrying out simulation analysis according to the generated multi-section constraint action sequence to obtain an assembly gap (j) and an assembly deformation def (i) at each observation point, and calculating the fitness F obj ；
Step 40, judgment F obj If the current sequence is less than a set value, jumping out of the loop and outputting the current sequence as the optimal multi-section constraint action sequence, if not, evolving the multi-section constraint action sequence through an ant colony optimization algorithm, and then entering step 50;
step 50, calculating the assembly clearance gap (j) and the assembly deformation def (i) at each observation point by using finite element analysis software, and acquiring the fitness F obj And then returns to step 40.
Preferably, in the step 40, the evolving the multi-section constraint action sequence through the ant colony optimization algorithm further includes:
adding global pheromone for the evolutionary process of the ant colony optimization algorithm based on a social level system, and adding additional global pheromone xi when the footmarks of ants k from the segmented air bag u to the segmented air bag v are similar to the footmarks of leader ants a, b and c uv Encourages the ants to use the footprints of the collar-sleeve ants,
χ uv ＝ζ uv +ξ uv
wherein theta represents the evaporation coefficient of the pheromone on the footprint of the ant, 1-theta represents the persistence coefficient of the pheromone on the footprint of the ant, and l a ,l b ,l c The fitness function values, zeta, of ants a, b, c, respectively uv Is the pheromone xi of the conventional ant colony algorithm uv Is a global pheromone, χ uv Is the pheromone of the optimized ant colony algorithm.
The embodiment of the invention at least has the following technical effects or advantages:
1. the wing box assembly gap control device based on the inflation and compaction of the segmented air bags can realize that: when the automatic hole making equipment is adopted for making holes of the pre-connection holes, the interlayer clearance between the wall plate and the framework of the aircraft wing box is effectively inhibited;
2. the method for optimizing the multi-section constraint sequence of the wing box assembly gap of the airplane is based on group intelligent optimization, can realize the arrangement combination optimization of the multi-section constraint of the segmented air bag used for inhibiting the assembly gap, and can provide theoretical guidance and technical support for the formulation of the digital assembly process specification of the airplane wing.
The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.
Drawings
The invention will be further described with reference to the following examples with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a gap control unit according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a multi-section constraint implementation of assembly gap control in accordance with an embodiment of the present invention.
Detailed Description
The technical scheme in the embodiment of the application has the following general idea:
s1, considering that the framework and the wall plate of the outer wing box of the domestic large aircraft are metal structures at present and in a future period of time, and the actual assembly process of the outer wing box of the domestic large aircraft is based on the framework shape, and the assembly gaps are mainly distributed at the maximum section of the rib between the framework and the wall plate. Providing an assembly gap control strategy based on multi-section constraint by adopting pressing force, and realizing effective fitting of the wall plate and the framework in a pressing stage;
s2, the multi-section constraint sequence optimization nature when the sectional air bags sequentially press the wall plates is a permutation and combination optimization problem, and the problem can be solved by adopting an ant colony optimization algorithm;
s3, considering that the optimization problem of the multi-section constraint action sequence is a nonlinear optimization problem, and the relation between the objective function and the design variable cannot be expressed by an analytic expression. Therefore, the ant colony algorithm and finite element analysis are combined, and the multi-section constraint action sequence optimization is implemented;
s4, considering that the problem of premature convergence exists when the ant colony optimization algorithm is adopted to carry out multi-section constraint action sequence optimization, a new global pheromone strengthening and updating mechanism is added to the evolution process of the ant colony optimization algorithm based on the social level system in the Cantonese wolf optimizer.
The present embodiment firstly provides a wing box assembly gap control device, as shown in fig. 1, which includes at least two gap control units 1 (in practical operation, the number of the gap control units 1 may be set according to the requirement of the wing box assembly pre-connection, and is usually plural), each of the gap control units includes a front beam support 11, a back beam support 12, a wall plate pressing body 13, and plural segmented airbags 14;
one end of the front beam support 11 is connected with a front beam positioning tool 21, one end of the back beam support 12 is connected with a back beam positioning tool 22, two ends of the wallboard pressing main body 13 are fixedly connected with the other ends of the front beam support 11 and the back beam support 12 respectively, the segmented airbags 14 are fixedly arranged on the inner side of the arc of the wallboard pressing main body 13 in sequence, the wallboard pressing main body 13 is arranged on the outer side of the wallboard 23 through the segmented airbags 14 in a pressing mode, the wallboard 23 is pressed after being inflated through the segmented airbags, and the assembly gap 31 between the wallboard 23 and the framework 24 is eliminated.
In one possible embodiment, the front beam support 11 and the rear beam support 12 are movable in the thickness direction of the wing box by a set distance for adjusting the distance between the panel pressing body 13 and the panel 23, ensuring that the assembly gap control device presses the panel 23 in the inflated state of the segmented bag 14.
In a possible embodiment, the panel pressing body 13 is an arc-shaped pressing strip, and the radian of the arc-shaped pressing strip is consistent with that of the outer shape of the panel 23, so that the panel pressing strip can be well attached to the panel 23. In other embodiments, the working surface of the arc-shaped pressing strip is in a structural form similar to that of the wallboard appearance clamping plate, and the radian can be set according to the specific requirement of assembly clearance control.
On the basis of the wing box assembly gap control device, the present embodiment further provides a wing box assembly gap multi-section constraint sequence optimization method, which optimizes the inflation sequence of the segmented airbags, so as to better implement assembly gap control, as shown in fig. 2, including:
step 10, setting m assembly gap observation points at preset intervals on a connecting line of a wing box wall plate and a framework of the wing, setting n assembly deformation observation points at preset intervals on the wing box, and then constructing an optimization objective function G obj Minimizing the optimization objective function by adopting an ant colony optimization algorithm,
wherein gap (j) is the assembly gap at the jth assembly gap observation point, and j is equal to [1, m ]]Def (i) is the assembly deformation at the ith assembly deformation observation point, i e [1, n ]]Phi and phi are weight coefficients, v, set to balance the effect of assembly gap and assembly distortion on the optimization process j Weight, ω, for the jth set-up gap observation point i Weights for the ith assembly distortion observation point;
step 20, in finite element analysis software (for example, Abaqus), establishing a multi-section constraint finite element analysis model for compressing the segmented airbags according to the wing box assembly gap control device, and presetting N linear loads at N segmented airbags for applying the compression force of the segmented airbags;
step 30, designing a fitness function F according to the objective function obj Taking the inverse of the objective function as the fitness function, i.e. F obj ＝1/G obj (fitness is used for evaluating the quality degree of an individual, the larger the fitness is, the better the individual is, otherwise, the smaller the fitness is, the worse the individual is, in the multi-practical problem, the solved target is usually the minimum rather than the maximum benefit, so the target needing to be solved the minimum needs to be converted into the form of solving the maximum target according to the non-negative principle of a fitness function), a multi-section constraint action sequence is randomly generated to initialize ant colony algorithm variables, finite element analysis software is called, simulation analysis is carried out according to the generated multi-section constraint action sequence, the assembly gaps gap (j) and the assembly deformation def (i) at each observation point are obtained, and the fitness F is calculated obj ；
Step 40, judgment F obj If the current sequence is less than a set value, jumping out of the loop and outputting the current sequence as the optimal multi-section constraint action sequence, if not, evolving the multi-section constraint action sequence through an ant colony optimization algorithm, and then entering step 50;
step 50, calculating the assembly clearance gap (j) and the assembly deformation def (i) at each observation point by using finite element analysis software, and acquiring the fitness F obj And then returns to step 40.
And inflating the segmented air bag according to the output optimal multi-section constraint action sequence, so that the arrangement and combination of the multi-section constraints of the segmented air bag for the assembly gap suppression are optimized, and the assembly gap control and the assembly gap suppression are better realized.
In a possible implementation manner, in the step 40, the evolving the multi-section constraint action sequence through the ant colony optimization algorithm further includes:
adding global pheromone for the evolutionary process of the ant colony optimization algorithm based on the social ranking system, and when the footmark of the ant k from the segmented air bag u to the segmented air bag v is similar to the footmarks of the leader ants a, b and cWhen, add extra global pheromone xi uv Encourages the ants to use the footprints of the collar-sleeve ants,
χ uv ＝ζ uv +ξ uv
wherein theta represents the evaporation coefficient of the pheromone on the footprint of the ant, 1-theta represents the persistence coefficient of the pheromone on the footprint of the ant, and l a ,l b ,l c The fitness function values, zeta, of ant a, b, c uv Is the pheromone xi of the conventional ant colony algorithm uv Is a global pheromone, χ uv Is the pheromone of the optimized ant colony algorithm.
By adding global pheromones to the evolution process of the ant colony optimization algorithm, the problem of premature convergence possibly existing in the conventional ant colony algorithm can be avoided.
The wing box assembly gap control device based on segmented airbag inflation and compaction can effectively inhibit the interlayer gap between the wall plate and the framework of the aircraft wing box when an automatic hole making device is adopted to make a pre-connection hole; the method for optimizing the multi-section constraint sequence of the wing box assembly gap of the airplane is based on group intelligent optimization, can realize the arrangement combination optimization of the multi-section constraint of the segmented air bag used for inhibiting the assembly gap, and can provide theoretical guidance and technical support for the formulation of the digital assembly process specification of the airplane wing.
Although specific embodiments of the invention have been described above, it will be understood by those skilled in the art that the specific embodiments described are illustrative only and are not limiting upon the scope of the invention, and that equivalent modifications and variations can be made by those skilled in the art without departing from the spirit of the invention, which is to be limited only by the appended claims.
Claims (4)
1. A method for optimizing a multi-section constraint sequence of assembly gaps of wing boxes of wing is characterized by comprising the following steps: the device comprises at least two gap control units, wherein each gap control unit comprises a front beam support, a back beam support, a wall plate pressing main body and a plurality of segmented airbags;
one end of the front beam support is connected with the front beam positioning tool, one end of the back beam support is connected with the back beam positioning tool, two ends of the wallboard pressing main body are fixedly connected with the other ends of the front beam support and the back beam support respectively, the plurality of segmented air bags are fixedly arranged on the inner side of the arc of the wallboard pressing main body in sequence, the wallboard pressing main body is pressed on the outer side of the wallboard through the plurality of segmented air bags, and the wallboard is pressed to eliminate assembly gaps after the segmented air bags are inflated;
the method comprises the following steps:
step 10, setting m assembly gap observation points at preset intervals on a connecting line of a wing box wall plate and a framework of the wing, setting n assembly deformation observation points at preset intervals on the wing box, and then constructing an optimization objective function G obj Minimizing the optimization objective function by adopting an ant colony optimization algorithm,
wherein gap (j) is the assembly gap at the jth assembly gap observation point, and j belongs to [1, m ]]Def (i) is the assembly deformation at the ith assembly deformation observation point, i e [1, n ]]Phi and phi are weight coefficients, v, set to balance the effect of assembly gap and assembly distortion on the optimization process j Weight, ω, for the jth set-up gap observation point i Weights for the ith assembly distortion observation point;
step 20, in finite element analysis software, establishing a multi-section constraint finite element analysis model compressed by the segmented airbags according to the wing box assembly gap control device, and presetting N linear loads at N segmented airbags for applying the compression force of the segmented airbags;
step 30, designing a fitness function F according to the objective function obj Taking the reciprocal of the objective function as the fitnessFunction, i.e. F obj ＝1/G obj Randomly generating a multi-section constraint action sequence to initialize ant colony algorithm variables, calling finite element analysis software, carrying out simulation analysis according to the generated multi-section constraint action sequence to obtain assembly gaps gap (j) and assembly deformation def (i) at each observation point, and calculating the fitness F obj ；
Step 40, judgment F obj If the current sequence is less than a set value, jumping out of the loop and outputting the current sequence as the optimal multi-section constraint action sequence; if not, evolving the multi-section constraint action sequence through an ant colony optimization algorithm, and then entering step 50;
step 50, calculating the assembly clearance gap (j) and the assembly deformation def (i) at each observation point by using finite element analysis software, and acquiring the fitness F obj And then returns to step 40.
2. The method of claim 1, wherein: in step 40, the evolving the multi-section constraint action sequence through the ant colony optimization algorithm further includes:
adding global pheromone for the evolutionary process of the ant colony optimization algorithm based on a social level system, and adding additional global pheromone xi when the footmarks of ants k from the segmented air bag u to the segmented air bag v are similar to the footmarks of leader ants a, b and c uv Encourages the ants to use the footprints of the collar-sleeve ants,
χ uv ＝ζ uv +ξ uv
wherein theta represents the evaporation coefficient of the pheromone on the footprint of the ant, 1-theta represents the persistence coefficient of the pheromone on the footprint of the ant, and l a ,l b ,l c The fitness function values, zeta, of ant a, b, c uv Is the pheromone xi of the conventional ant colony algorithm uv Is a global pheromone, χ uv Is the pheromone of the optimized ant colony algorithm.
3. The method of claim 1, wherein: the front beam support and the back beam support can move within a set distance along the thickness direction of the wing box and are used for adjusting the distance between the wallboard pressing main body and the wallboard.
4. A method according to claim 1 or 3, characterized in that: the wallboard compresses tightly the main part and is an arc layering, the radian of arc layering is unanimous with the radian of wallboard appearance.
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