Nose cone acoustic liner hole end effector path planning method

Abstract

This invention discloses a path planning method for the end effector of borehole drilling in aero-engine nacelles, relating to the field of aero-engine manufacturing. The method includes the following steps: calculating the equivalent machining hole and its corresponding end effector machining pose parameters; constructing an objective function for the equivalent machining hole drilling path planning problem; establishing a multi-spindle drilling path optimization model for aero-engine nacelle acoustic liner robot; solving for the optimal drilling path; and proposing to initialize the population by selecting the smallest individual as the population individual. This invention obtains the shortest movement path for the multi-spindle drilling end effector, facilitating the efficiency and processing safety of acoustic liner hole drilling, thereby shortening the manufacturing cycle of aero-engine nacelle acoustic liner parts.

Description

Technical Field

[0001] This invention relates to the field of aero-engine manufacturing, and in particular to a method for planning the path of the end effector for the acoustic liner bore of an aero-engine nacelle. Background Technology

[0002] Aircraft engine noise is the primary source of aircraft noise, and fan noise is a major component of aircraft engine noise. Fan noise control level is a crucial indicator of the sophistication of modern aircraft engines. To reduce aircraft engine fan noise, an acoustic liner is installed inside the aircraft engine nacelle. Based on the Helmholtz resonance principle, sound energy is dissipated along the noise radiation propagation path through acoustic liner holes and honeycomb cavities. Because the large number, complex arrangement, and precise positioning of the acoustic liner holes all affect the acoustic impedance of the liner, the hole fabrication is a critical step in nacelle acoustic liner manufacturing.

[0003] Conventional single-spindle robotic hole-making systems are insufficient to meet the high-efficiency hole-making requirements of nacelle acoustic liner. To significantly improve the hole-making efficiency of acoustic liner, a multi-spindle robotic hole-making system for nacelle acoustic liner has been developed. The system uses a multi-spindle hole-making end effector to achieve array-style multi-spindle hole-making of the nacelle acoustic liner. The multi-spindle hole-making end effector can complete the machining of acoustic liner holes in one positioning operation, up to the same number as the number of spindles. The process of the multi-spindle hole-making end effector machining multiple acoustic liner holes at one time can be regarded as machining an equivalent hole. The number of acoustic liner holes corresponding to different equivalent holes is not the same.

[0004] When drilling holes in the acoustic liner of the nacelle, a large number of acoustic liner holes in the drilling area are mapped to a small number of equivalent machining holes. By optimizing the layout of these equivalent machining holes, the number of equivalent machining holes can be effectively reduced and the drilling efficiency improved. Based on the acoustic liner hole pose parameters corresponding to the equivalent machining holes, the end effector machining pose corresponding to different equivalent machining holes can be calculated. Given a fixed layout of equivalent machining holes and end effector machining pose, different drilling paths for equivalent machining holes have a causal relationship with the robot's drilling efficiency. Inappropriate drilling paths may worsen drilling efficiency and machining safety.

[0005] In view of this, the inventors of this case conducted in-depth research on the above-mentioned problems, which led to the creation of this case. Summary of the Invention

[0006] The purpose of this invention is to provide a path planning method for the end effector of the acoustic liner hole making process in aero-engine nacelles, so as to obtain the shortest movement path of the multi-spindle hole making end effector, thereby facilitating the efficiency and processing safety of the acoustic liner hole making process.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The end effector path planning method for the acoustic liner orifice of an aero-engine nacelle is carried out according to the following steps:

[0009] S1, through optimization of the equivalent machining hole layout and calculation of the end effector machining pose, k equivalent machining holes are obtained. and its corresponding end effector machining pose parameters;

[0010] Define the i-th equivalent machined hole The end effector machining pose parameter six-tuple is ;

[0011] use This indicates the machining sequence of equivalent holes during the hole-making process. Construct the objective function for the equivalent machining hole-making path planning problem. The goal of the plan is to optimize the processing sequence. The state space constituted Find the objective function within. Minimize processing sequence ;

[0012] (1)

[0013] in:

[0014] These are the coordinates of the equivalent machined hole positions.

[0015] The end effector machining posture is represented by ZXY Euler angles;

[0016] For the machining sequence of a certain equivalent machining hole At that time, the first and The distance between equivalent machined holes ;

[0017] The first and The difference in ZXY Euler angles for each equivalent machined hole. , , ;

[0018] and The weights are set to balance the length of the path and the smoothness of the end effector's machining posture;

[0019] These are the weighting coefficients for the Euler angle difference of ZXY, respectively;

[0020] S2, with hole-making path and end effector attitude smoothness weighted sum The reciprocal of this comprehensive evaluation index is the fitness function, and a multi-spindle hole-making path optimization model for the acoustic liner robot of an aero-engine nacelle is established. ;

[0021] The optimal drilling path is obtained by using a genetic optimization algorithm. ;

[0022] (2);

[0023] S3 proposes to initialize the population by selecting individuals and generating an equivalent machining hole processing sequence population size during population initialization. of The number of individuals is multiples of the number of individuals;

[0024] Will smallest Each individual is initialized as a population individual.

[0025] Preferably, the equivalent machining hole layout optimization is based on the function Given a set of all possible equivalent machined holes with a certain arrangement order, generate a set of equivalent machined holes, including their layout and number of elements, where the machining points of the acoustic liner holes are mutually exclusive and the corresponding machining points cover the entire drilling area. This is done by following these steps:

[0026] SA1 defines the set of all possible equivalent machined holes. Arrange the equivalent machined holes in sequence Chromosomes as part of a genetic algorithm;

[0027] If the equivalent machining hole arrangement order contain If there are equivalent processing well numbers, then the chromosome is composed of... Each gene is composed of a single gene, and each gene corresponds to an equivalent processing pore layout coordinate. ;

[0028] in:

[0029] The x-coordinate of the equivalent machined hole on the plane of the hole-making area is its positional coordinate.

[0030] This represents the vertical coordinate of the equivalent machined hole on the plane of the hole-making area.

[0031] Equivalent machined holes defined in tuple form;

[0032] SA2, perform parameter initialization: set the initial population size for the equivalent machining hole arrangement order as follows. ,and The chromosome length in the equivalence processing pore arrangement order of the population is m;

[0033] Set the maximum number of iterations. Crossover probability Probability of mutation Interval ratio Initial values ​​for, etc.;

[0034] SA3, select all possible equivalent machined holes according to The coordinates are arranged in both sequential and reverse order. These two arrangements are used as two equivalent machining hole arrangement sequences (chromosomes). These two arrangements are then randomly shuffled to generate the remaining sequences. The chromosomes arranged in the equivalent processing pore sequence constitute the initial population of the equivalent processing pore sequence;

[0035] SA4, calculate the fitness function ;

[0036] By adopting a greedy selection strategy, based on the set of all possible equivalent machining holes in a certain order, we obtain the set of equivalent machining holes with the smallest number of equivalent machining holes and their layout.

[0037] (A1);

[0038] (A2);

[0039] in:

[0040] Let be a function value of the chromosome representing the equivalent machining hole arrangement order, and let be the preferred number of equivalent machining holes, determined by the function. The solution is obtained;

[0041] This is a preferred set of equivalent machined holes;

[0042] In SA11, let ,in Then with a certain probability Accept the new solution, as follows:

[0043] ;

[0044] in:

[0045] The energy of the current optimal solution;

[0046] The energy for the new solution.

[0047] Preferably, the method for generating equal-sized machined holes is performed according to the following steps:

[0048] SB1 unfolds the curved surface of the nacelle acoustic lining perforation area into a plane, and completes the process according to a certain row spacing and column spacing. Each sound liner hole processing point After arrangement, equivalent machining holes are used. The machining points of the acoustic liner holes are equivalent, and the equivalent machining holes are defined in the form of tuples. ;

[0049] (B1);

[0050] in:

[0051] The number of acoustic liner holes machined after positioning the equivalent machining holes. ;

[0052] , is the set of machining hole points on the plane corresponding to the equivalent machining holes and The set has no more than ;

[0053] These are the machining points for the acoustic liner holes to be machined, corresponding to each spindle arranged in sequence. The set has fewer than The machining point corresponding to the spindle that does not participate in machining is empty;

[0054] SB2 defines the boundary direction of the bottom surface of the multi-spindle hole-making end effector as being the same as the row and column direction of the acoustic liner holes within the hole-making area;

[0055] The drilling operation of the multi-spindle drilling end effector is regarded as a sequential scanning operation of the acoustic liner hole machining points. The position of the multi-spindle drilling end effector covering the acoustic liner hole machining points is determined, and thus... One equivalent machining hole and the corresponding set of acoustic liner hole processing points Finally, a set of machining points corresponding to the acoustic liner holes of the equivalent machining holes is obtained. ;

[0056] (B2);

[0057] in:

[0058] Let S be the position of the set of equivalent machined hole locations in the set S.

[0059] The set of all equivalent machined holes corresponding to the sound liner holes is a subset of the set S;

[0060] SB3, under the condition of satisfying formulas (B1) and (B2), generates equivalent machined holes based on a greedy selection strategy, prioritizing the generation of the number of machined holes. Larger equivalent machined holes In the single-positioning machining process of the multi-spindle hole-making end effector, each spindle is fully utilized. The specific steps are as follows:

[0061] SB31, determined based on the number of spindles in the multi-spindle hole-making end effector. ,make , ;

[0062] SB32, select the appropriate one according to the current equivalent machining hole sequence. Enter SB33;

[0063] SB33, if There is Enter SB34;

[0064] Otherwise Return to SB32;

[0065] SB34, if ,make , Enter SB35;

[0066] Otherwise Return to SB32;

[0067] SB35, if Established and entered SB37;

[0068] Otherwise proceed to SB36;

[0069] SB36, Judgment Is it true? If it is true, then... and Enter SB37;

[0070] Otherwise Enter SB32;

[0071] SB37 outputs the set of all equivalent machined holes. ;

[0072] in:

[0073] This is a set of records of the points that have been processed.

[0074] Preferably, when machining the acoustic liner holes in the nacelle, all acoustic liner holes in the drilling area are machined, and the same acoustic liner hole will not be machined repeatedly. Formula (B2) is modified to include the constraint condition of formula (B3).

[0075] (B3).

[0076] Preferably, .

[0077] Preferably, the end effector machining pose planning method is performed according to the following steps:

[0078] SC1, through mapping The simultaneous machining of multiple acoustic liner holes based on a multi-spindle hole-making end effector is mapped to the machining of a single acoustic liner hole based on a single-spindle hole-making end effector. Each sound liner has ;

[0079] (C1);

[0080] in:

[0081] ( The acoustic liner holes, machined synchronously in a single positioning operation by a multi-spindle end effector, are located in the nacelle acoustic liner product coordinate system. The pose parameters in the middle;

[0082] These are the coordinates of the acoustic liner hole;

[0083] for The normal vector of the acoustic lining surface at that location;

[0084] For the equivalent machined hole coordinate system in the product coordinate system The pose matrix in the middle;

[0085] SC2 defines that the axis of the acoustic liner hole is collinear with the normal vector of the acoustic liner surface at its location, based on mapping. The normal vector of the acoustic liner hole is used to calculate the equivalent machined hole coordinate system. The shaft, and the specific steps include;

[0086] SC21, according to the mapping When machining a certain equivalent machining hole, determine the corresponding actual machined acoustic liner hole, and mark the position coordinates of that acoustic liner hole as follows: ;

[0087] SC22 uses offline programming software to extract the normal vector of the acoustic liner surface at the acoustic liner hole. ;

[0088] SC23 normalizes the mean value of the normal vector of the actual acoustic liner hole corresponding to the equivalent machined hole, and uses it as the coordinate system of the equivalent machined hole. Axial direction;

[0089] (C2);

[0090] in:

[0091] The average normal vector of the acoustic liner hole;

[0092] Equivalent machining hole coordinate system of Axial unit vector;

[0093] SC3, when mapping Number of medium acoustic liner holes At that time, enter SC4;

[0094] Mapping Number of medium acoustic liner holes At that time, enter SC5;

[0095] in:

[0096] It is a natural number greater than 0;

[0097] SC4, setting the coordinate system of the equivalent machined hole. Axial direction Simultaneously, based on the design geometric parameters of the end effector spindle array, the origin of the equivalent machining hole coordinate system is calculated. The specific steps include:

[0098] SC41, based on robot base coordinate system calibration results Obtain the robot's base coordinate system of Negative unit vector in the nacelle acoustic liner product coordinate system Description in ;

[0099] SC42, and Cross product yields ,Will Unitization As the coordinate system of the equivalent machined hole Axial direction;

[0100] (C3);

[0101] SC43, unit vector and Cross product, yielding the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ;

[0102] (C4);

[0103] SC44, when Establish a coordinate system on the machining plane, and use the coordinates of ... and for shaft and In the axial direction, the coordinates of the equivalent machined hole in this coordinate system are: ,in It depends on the design geometry of the end effector spindle array;

[0104] SC45, solve for the position coordinates of the origin of the equivalent machined hole coordinate system. ;

[0105] (C5);

[0106] SC5, based on the position coordinates of any two acoustic liner holes, determines the equivalent machined hole coordinate system. The axis direction and origin, and the specific steps include:

[0107] The SC51 multi-spindle hole-making end effector features parallel spindle axes and flush ends. Machining an equivalent hole can be considered as all hole-making spindles operating on the same machining plane. The machining plane equation is set as follows: [Machining the acoustic liner hole] ;

[0108] According to SC2, machine the plane. The normal vector is Make the machining plane coefficients in the equation They are respectively equal to The sum of squares of the deviations between the actual acoustic liner hole position coordinates and the fitted plane is calculated using the least squares algorithm. Minimum coefficient ;

[0109] (C6);

[0110] in:

[0111] Let be the objective function, and let be the optimization model. ;

[0112] For the first The coordinates of the location of each acoustic liner hole;

[0113] SC52, Calculate the mapping Coordinates of the location of the medium acoustic liner hole On the machining plane Projection on;

[0114] (C7);

[0115] (C8);

[0116] in:

[0117] For the first The coordinates of the location of each acoustic vent The projection;

[0118] For the first The coordinates of the location of each acoustic liner hole;

[0119] SC53, on the machined plane Construct a Cartesian coordinate system in the plane to calculate vectors. and origin Determine the coordinate system for the nacelle acoustic liner product. The equivalent machining hole coordinate system The axis direction and origin, the specific process includes:

[0120] SC531, according to formula (C7), the first... and The coordinates of the position of each acoustic liner hole are on the machining plane. Projection on and ;

[0121] SC532, Calculate the machining plane Upward projection Pointing to projection vector And after unitization, we obtain ;

[0122] SC533, the machining plane obtained by combining formula (C2) unit normal vector We can obtain this through cross product. ;

[0123] SC534, based on unit vectors and Establish a Cartesian coordinate system ;

[0124] SC535 can calculate vectors according to formulas (C9) and (C10). and origin ;

[0125] (C9);

[0126] (C10);

[0127] in: ;

[0128] SC536, for vectors Unitization This will serve as the coordinate system for the equivalent machined holes. Axial direction ;

[0129] SC537, unit vector and Cross product, to obtain the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ;

[0130] (C11);

[0131] Take the coordinates of one of the acoustic liner holes as the origin, establish a Cartesian coordinate system, and calculate the vector according to the above process. and origin ;

[0132] SC54, based on the equivalent machining hole coordinate system Axial unit vector and in-situ position coordinates The equivalent machining hole is obtained in the nacelle acoustic liner product coordinate system. pose description matrix Transform it to the robot's base coordinate system This refers to the target machining pose of the multi-spindle end effector.

[0133] (C12);

[0134] (C13);

[0135] in:

[0136] The calibration results for the robot's base coordinate system.

[0137] Preferably, the multi-spindle bore end effector includes an actuator frame, a spindle assembly, a feed assembly, a solenoid valve assembly, and a pressure foot assembly;

[0138] The actuator frame includes a front plate and a rear plate arranged opposite to each other. The spindle assembly, feed assembly and solenoid valve assembly are all arranged in the inner cavity of the actuator frame. The pressure foot assembly is arranged on the rear plate and located on the outside of the actuator frame. The feed assembly is arranged on the rear plate. One end of the spindle assembly is arranged corresponding to the feed assembly, and the other end passes through the front plate and is connected to the pressure foot assembly. The feed assembly is used to control the extension or retraction of the corresponding spindle assembly and pressure foot assembly.

[0139] It also includes a hole-making position error measurement system for measuring the angle between the hole-making direction of the equivalent machined hole of the multi-spindle hole-making end effector and the normal of the curved surface at the equivalent machined hole on the nacelle acoustic liner. The hole-making position error measurement system includes a laser displacement sensor group installed on the multi-spindle hole-making end effector. The laser displacement sensor group includes four laser displacement sensors for measuring the deviation between the actual tool coordinate system Z-axis and the ideal tool coordinate system Z-axis. The four laser displacement sensors are respectively installed at the four corners of the front plate, and the coordinate system Z-axis is parallel to the hole-making direction.

[0140] It also includes a hole-making direction deviation measurement system for measuring the position coordinates of pre-made reference holes on the nacelle acoustic liner and calculating the hole-making position error at each reference hole position coordinate. The hole-making direction deviation measurement system includes a vision unit mounted on the multi-spindle hole-making end effector. The vision unit includes a light source for providing good shooting lighting conditions and an industrial camera and telecentric lens for measuring the actual position coordinates of the reference holes. The direction of the light source is parallel to the direction of the spindle assembly.

[0141] Preferably, the spindle assembly includes n spindles, the feed assembly includes n cylinders, and the pressure foot includes n pressure feet, where n is an even number greater than 0. Each spindle and cylinder is configured in a one-to-one correspondence with a pressure foot, and each cylinder independently controls the extension and retraction of its corresponding spindle and pressure foot. The solenoid valve assembly includes n+1 solenoid valves, each of which has two interfaces: an air inlet and an air outlet. The n solenoid valves are used to control the extension and retraction of the cylinders, and the other solenoid valve is used for controlling the spindle air cooling switch.

[0142] A spring is provided between each presser foot and the front plate to press the presser foot against the surface of the sound liner perforated panel. The spring is correspondingly sleeved on the outer periphery of the spindle.

[0143] The front panel is also equipped with an ultrasonic sensor group, which includes four ultrasonic sensors for collision detection. The four ultrasonic sensors are installed at the four corners of the front panel.

[0144] By adopting the aforementioned design scheme, the beneficial effects of the present invention are as follows: The end effector path planning method for drilling holes in the acoustic liner of aero-engine nacelles of the present invention obtains the shortest movement path of the multi-spindle drilling end effector, which facilitates ensuring the efficiency and processing safety of the acoustic liner hole drilling, thereby shortening the manufacturing cycle of the acoustic liner parts of aero-engine nacelles, and providing a theoretical basis and technical support for specifying the multi-spindle drilling process specifications for aero-engine nacelle acoustic liner robots. Attached Figure Description

[0145] Figure 1 This is a schematic diagram of the spindle distribution of the multi-spindle hole-making end effector in this invention;

[0146] Figure 2 This is an equivalent schematic diagram of the machining points of the acoustic liner holes in this invention;

[0147] Figure 3 This refers to the machining limit position of the multi-spindle hole-making end effector in the hole-making area in this invention;

[0148] Figure 4 This is a flowchart illustrating the main steps of the equivalent machining hole layout for multi-spindle hole making according to the present invention.

[0149] Figure 5 This is a schematic diagram of the unit vector of the X-axis of the equivalent machining hole coordinate system when machining a single acoustic liner hole in this invention;

[0150] Figure 6 This is a schematic diagram illustrating the calculation of the origin of the equivalent machined hole when machining a single acoustic liner hole in this invention;

[0151] Figure 7 This is a schematic diagram of the planar coordinate system for machining the planar structure when machining multiple acoustic liner holes in this invention;

[0152] Figure 8 For calculating vectors in this invention and origin A diagram illustrating the audit relationship;

[0153] Figure 9 This is an isometric view of the multi-spindle bore end effector of the present invention;

[0154] Figure 10 This is a front view of the multi-spindle bore end effector of the present invention;

[0155] Figure 11 This is a top view of the multi-spindle bore end effector of the present invention;

[0156] Figure 12 This is a side view of the multi-spindle bore end effector of the present invention;

[0157] In the figure: multi-spindle end effector 3, actuator frame 31, first side plate 311, second side plate 312, spindle assembly 32, feed assembly 33, solenoid valve assembly 34, valve island 341, pressure foot assembly 35, spring 351, ultrasonic sensor assembly 36, laser displacement sensor assembly 37, vision unit 38, vacuum tube assembly 39. Detailed Implementation

[0158] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0159] Reference Figures 1 to 12

[0160] The end effector path planning method for the acoustic liner orifice of an aero-engine nacelle is carried out according to the following steps:

[0161] S1, through optimization of the equivalent machining hole layout and calculation of the end effector machining pose, k equivalent machining holes are obtained. and its corresponding end effector machining pose parameters;

[0162] Define the i-th equivalent machined hole The end effector machining pose parameter six-tuple is ;

[0163] use This indicates the machining sequence of equivalent holes during the hole-making process. Construct the objective function for the equivalent machining hole-making path planning problem. The goal of the plan is to optimize the processing sequence. The state space constituted Find the objective function within. Minimize processing sequence ;

[0164] (1)

[0165] in:

[0166] These are the coordinates of the equivalent machined hole positions.

[0167] The end effector machining posture is represented by ZXY Euler angles;

[0168] For the machining sequence of a certain equivalent machining hole At that time, the first and The distance between equivalent machined holes ;

[0169] The first and The difference in ZXY Euler angles for each equivalent machined hole. , , ;

[0170] and The weights are set to balance the length of the path and the smoothness of the end effector's machining posture;

[0171] These are the weighting coefficients for the Euler angle difference of ZXY, respectively;

[0172] S2, with hole-making path and end effector attitude smoothness weighted sum The reciprocal of this comprehensive evaluation index is the fitness function, and a multi-spindle hole-making path optimization model for the acoustic liner robot of an aero-engine nacelle is established. ;

[0173] The optimal drilling path is obtained by using a genetic optimization algorithm. ;

[0174] (2)

[0175] S3 proposes to initialize the population by selecting individuals and generating an equivalent machining hole processing sequence population size during population initialization. of The number of individuals is multiples of the number of individuals;

[0176] Will smallest Each individual is initialized as a population individual.

[0177] Preferably, the equivalent machining hole layout optimization is based on the function Given a set of all possible equivalent machined holes with a certain arrangement order, generate a set of equivalent machined holes, including their layout and number of elements, where the machining points of the acoustic liner holes are mutually exclusive and the corresponding machining points cover the entire drilling area. This is done by following these steps:

[0178] SA1 defines the set of all possible equivalent machined holes. Arrange the equivalent machined holes in sequence Chromosomes as part of a genetic algorithm;

[0179] If the equivalent machining hole arrangement order contain If there are equivalent processing well numbers, then the chromosome is composed of... Each gene is composed of a single gene, and each gene corresponds to an equivalent processing pore layout coordinate. ;

[0180] in:

[0181] The x-coordinate of the equivalent machined hole on the plane of the hole-making area is its positional coordinate.

[0182] This represents the vertical coordinate of the equivalent machined hole on the plane of the hole-making area.

[0183] Equivalent machined holes defined in tuple form;

[0184] SA2, perform parameter initialization: set the initial population size for the equivalent machining hole arrangement order as follows. ,and The chromosome length in the equivalence processing pore arrangement order of the population is m;

[0185] Set the maximum number of iterations. Crossover probability Probability of mutation Interval ratio Initial values ​​for, etc.;

[0186] SA3, select all possible equivalent machined holes according to The coordinates are arranged in both sequential and reverse order. These two arrangements are used as two equivalent machining hole arrangement sequences (chromosomes). These two arrangements are then randomly shuffled to generate the remaining sequences. The chromosomes arranged in the equivalent processing pore sequence constitute the initial population of the equivalent processing pore sequence;

[0187] SA4, calculate the fitness function ;

[0188] By adopting a greedy selection strategy, based on the set of all possible equivalent machining holes in a certain order, we obtain the set of equivalent machining holes with the smallest number of equivalent machining holes and their layout.

[0189] (A1);

[0190] (A2);

[0191] in:

[0192] Let be a function value of the chromosome representing the equivalent machining hole arrangement order, and let be the preferred number of equivalent machining holes, determined by the function. The solution is obtained;

[0193] This is a preferred set of equivalent machined holes;

[0194] Coordinates of each element for Layout of intermediate-cost machined holes;

[0195] SA5 updates each chromosome in the population with equivalent processing pore arrangement by selecting chromosomes with equivalent processing pore arrangement order and by crossover and inversion mutations of genes with equivalent processing pore layout coordinates.

[0196] After SA6 and SA5, the offspring population will be determined according to the interval ratio. The populations of equivalent machining hole arrangements retained from the parent and offspring generations are recombined to obtain a new population of equivalent machining hole arrangements;

[0197] SA7, increment the algorithm iteration count by 1 if the algorithm iteration count reaches the maximum iteration count. Enter SA8;

[0198] Otherwise, return to SA4;

[0199] SA8 is the equivalent processing hole arrangement sequence chromosome with the best fitness in the population from which the equivalent processing hole arrangement sequence chromosome is output.

[0200] SA9, initial values ​​for simulated annealing algorithm parameters: The initial temperature is specified as... Set the current temperature Minimum temperature Cooling rate Chain length ;

[0201] SA10, in the simulated annealing algorithm, creates a new solution for the equivalent machining hole arrangement order based on the inversion mutation factor;

[0202] SA11, according to The criterion accepts a new solution for the equivalent machining hole arrangement order. The specific process is as follows: [The criterion is then used to] convert the function-based [method / method]... And the arrangement order of equivalent machined holes, and the preferred number of equivalent machined holes. Energy as a solution;

[0203] SA12, when temperature At this time, the cooling process ends, and it enters SA14;

[0204] If the current temperature Temperature iteration After that, Return to SA10;

[0205] SA13, obtained through SA12, yields the minimum energy value in the optimal solution for the equivalent machining hole arrangement sequence. ;

[0206] SA14, the equivalent machining hole arrangement order corresponding to the minimum energy is the global optimal solution of the genetic-simulated annealing optimization process, and the minimum energy corresponds to... Another output of the function Coordinates of each element The optimal equivalent machining hole layout.

[0207] Preferably, SA5 uses trigonometric functions to dynamically and nonlinearly adjust the crossover probability and mutation probability based on the fitness function values ​​of each chromosome during the population iteration process of the equivalent processing hole arrangement order, so as to accelerate the convergence speed of the algorithm.

[0208] Preferably, in SA11, let ,in Then with a certain probability Accept the new solution, as follows:

[0209] ;

[0210] in:

[0211] The energy of the current optimal solution;

[0212] The energy for the new solution.

[0213] Preferably, the method for generating equal-sized machined holes is performed according to the following steps:

[0214] SB1 unfolds the curved surface of the nacelle acoustic lining perforation area into a plane, and completes the process according to a certain row spacing and column spacing. Each sound liner hole processing point After arrangement, equivalent machining holes are used. The machining points of the acoustic liner holes are equivalent, and the equivalent machining holes are defined in the form of tuples. ;

[0215] (B1);

[0216] in:

[0217] The number of acoustic liner holes machined after positioning the equivalent machining holes. ;

[0218] , is the set of machining hole points on the plane corresponding to the equivalent machining holes and The set has no more than ;

[0219] These are the machining points for the acoustic liner holes to be machined, corresponding to each spindle arranged in sequence. The set has fewer than The machining point corresponding to the spindle that does not participate in machining is empty;

[0220] SB2 defines the boundary direction of the bottom surface of the multi-spindle hole-making end effector as being the same as the row and column direction of the acoustic liner holes within the hole-making area;

[0221] The drilling operation of the multi-spindle drilling end effector is regarded as a sequential scanning operation of the acoustic liner hole machining points. The position of the multi-spindle drilling end effector covering the acoustic liner hole machining points is determined, and thus... One equivalent machining hole and the corresponding set of acoustic liner hole processing points Finally, a set of machining points corresponding to the acoustic liner holes of the equivalent machining holes is obtained. ;

[0222] (B2);

[0223] in:

[0224] Let S be the position of the set of equivalent machined hole locations in the set S.

[0225] The set of all equivalent machined holes corresponding to the sound liner holes is a subset of the set S;

[0226] SB3, under the condition of satisfying formulas (B1) and (B2), generates equivalent machined holes based on a greedy selection strategy, prioritizing the generation of the number of machined holes. Larger equivalent machined holes In the single-positioning machining process of the multi-spindle hole-making end effector, each spindle is fully utilized. The specific steps are as follows:

[0227] SB31, determined based on the number of spindles in the multi-spindle hole-making end effector. ,make , ;

[0228] SB32, select the appropriate one according to the current equivalent machining hole sequence. Enter SB33;

[0229] SB33, if There is Enter SB34;

[0230] Otherwise Return to SB32;

[0231] SB34, if ,make , Enter SB35;

[0232] Otherwise Return to SB32;

[0233] SB35, if Established and entered SB37;

[0234] Otherwise proceed to SB36;

[0235] SB36, Judgment Is it true? If it is true, then... and Enter SB37;

[0236] Otherwise Enter SB32;

[0237] SB37 outputs the set of all equivalent machined holes. ;

[0238] in:

[0239] This is a set of records of the points that have been processed.

[0240] Preferably, when machining the acoustic liner holes in the nacelle, all acoustic liner holes in the drilling area are machined, and the same acoustic liner hole will not be machined repeatedly. Formula (B2) is modified to include the constraint condition of formula (B3).

[0241] (B3).

[0242] Preferably, .

[0243] Preferably, the end effector machining pose planning method is performed according to the following steps:

[0244] SC1, through mapping The simultaneous machining of multiple acoustic liner holes based on a multi-spindle hole-making end effector is mapped to the machining of a single acoustic liner hole based on a single-spindle hole-making end effector. Each sound liner has ;

[0245] (C1);

[0246] in:

[0247] ( The acoustic liner holes, machined synchronously in a single positioning operation by a multi-spindle end effector, are located in the nacelle acoustic liner product coordinate system. The pose parameters in the middle;

[0248] These are the coordinates of the acoustic liner hole;

[0249] for The normal vector of the acoustic lining surface at that location;

[0250] For the equivalent machined hole coordinate system in the product coordinate system The pose matrix in the middle;

[0251] SC2 defines that the axis of the acoustic liner hole is collinear with the normal vector of the acoustic liner surface at its location, based on mapping. The normal vector of the acoustic liner hole is used to calculate the equivalent machined hole coordinate system. The shaft, and the specific steps include;

[0252] SC21, according to the mapping When machining a certain equivalent machining hole, determine the corresponding actual machined acoustic liner hole, and mark the position coordinates of that acoustic liner hole as follows: ;

[0253] SC22 uses offline programming software to extract the normal vector of the acoustic liner surface at the acoustic liner hole. ;

[0254] SC23 normalizes the mean value of the normal vector of the actual acoustic liner hole corresponding to the equivalent machined hole, and uses it as the coordinate system of the equivalent machined hole. Axial direction;

[0255] (C2);

[0256] in:

[0257] The average normal vector of the acoustic liner hole;

[0258] Equivalent machining hole coordinate system of Axial unit vector;

[0259] SC3, when mapping Number of medium acoustic liner holes At that time, enter SC4;

[0260] Mapping Number of medium acoustic liner holes At that time, enter SC5;

[0261] in:

[0262] It is a natural number greater than 0;

[0263] SC4, setting the coordinate system of the equivalent machined hole. Axial direction Simultaneously, based on the design geometric parameters of the end effector spindle array, the origin of the equivalent machining hole coordinate system is calculated. The specific steps include:

[0264] SC41, based on robot base coordinate system calibration results Obtain the robot's base coordinate system of Negative unit vector in the nacelle acoustic liner product coordinate system Description in ;

[0265] SC42, and Cross product yields ,Will Unitization As the coordinate system of the equivalent machined hole Axial direction;

[0266] (C3);

[0267] SC43, unit vector and Cross product, yielding the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ;

[0268] (C4);

[0269] SC44, when Establish a coordinate system on the machining plane, and use the coordinates of ... and for shaft and In the axial direction, the coordinates of the equivalent machined hole in this coordinate system are: ,in It depends on the design geometry of the end effector spindle array;

[0270] SC45, solve for the position coordinates of the origin of the equivalent machined hole coordinate system. ;

[0271] (C5);

[0272] SC5, based on the position coordinates of any two acoustic liner holes, determines the equivalent machined hole coordinate system. The axis direction and origin, and the specific steps include:

[0273] The SC51 multi-spindle hole-making end effector features parallel spindle axes and flush ends. Machining an equivalent hole can be considered as all hole-making spindles operating on the same machining plane. The machining plane equation is set as follows: [Machining the acoustic liner hole] ;

[0274] According to SC2, machine the plane. The normal vector is Make the machining plane coefficients in the equation They are respectively equal to The sum of squares of the deviations between the actual acoustic liner hole position coordinates and the fitted plane is calculated using the least squares algorithm. Minimum coefficient ;

[0275] (C6);

[0276] in:

[0277] Let be the objective function, and let be the optimization model. ;

[0278] For the first The coordinates of the location of each acoustic liner hole;

[0279] SC52, Calculate the mapping Coordinates of the location of the medium acoustic liner hole On the machining plane Projection on;

[0280] (C7);

[0281] (C8);

[0282] in:

[0283] For the first The coordinates of the location of each acoustic vent The projection;

[0284] For the first The coordinates of the location of each acoustic liner hole;

[0285] SC53, on the machined plane Construct a Cartesian coordinate system in the plane to calculate vectors. and origin Determine the coordinate system for the nacelle acoustic liner product. The equivalent machining hole coordinate system The axis direction and origin, the specific process includes:

[0286] SC531, according to formula (C7), the first... and The coordinates of the position of each acoustic liner hole are on the machining plane. Projection on and ;

[0287] SC532, Calculate the machining plane Upward projection Pointing to projection vector And after unitization, we obtain ;

[0288] SC533, the machining plane obtained by combining formula (C2) unit normal vector We can obtain this through cross product. ;

[0289] SC534, based on unit vectors and Establish a Cartesian coordinate system ;

[0290] SC535 can calculate vectors according to formulas (C9) and (C10). and origin ;

[0291] (C9);

[0292] (C10);

[0293] in: ;

[0294] SC536, for vectors Unitization This will serve as the coordinate system for the equivalent machined holes. Axial direction ;

[0295] SC537, unit vector and Cross product, to obtain the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ;

[0296] (C11);

[0297] Take the coordinates of one of the acoustic liner holes as the origin, establish a Cartesian coordinate system, and calculate the vector according to the above process. and origin ;

[0298] SC54, based on the equivalent machining hole coordinate system Axial unit vector and in-situ position coordinates The equivalent machining hole is obtained in the nacelle acoustic liner product coordinate system. pose description matrix Transform it to the robot's base coordinate system This refers to the target machining pose of the multi-spindle end effector.

[0299] (C12);

[0300] (C13);

[0301] in:

[0302] The calibration results for the robot's base coordinate system.

[0303] Preferably, the multi-spindle bore end effector 3 is connected to the robotic arm via a flange. The multi-spindle bore end effector 3 includes an actuator frame 31, a spindle assembly 32, a feed assembly 33, a solenoid valve assembly 34, a pressure foot assembly 35, an ultrasonic sensor assembly 36, a laser displacement sensor assembly 37, and a vision unit 38. The actuator frame 31 is the mounting base for each component in the multi-spindle bore end effector 3.

[0304] The actuator frame 31 has a cubic frame structure. Two opposite side plates of the actuator frame 31 are defined as the first side plate 311 and the second side plate 312. The pressure foot assembly 35, the ultrasonic sensor assembly 36, the laser displacement sensor assembly 37 and the vision unit 38 are all mounted on the first side plate 311. The feed assembly 33 and the solenoid valve assembly 34 are all mounted on the second side plate 312. The spindle assembly 32 is mounted inside the actuator frame 31, and one end passes through the first side plate 311 and is correspondingly connected to the pressure foot assembly 35. The feed assembly 33 is used to control the extension or retraction of the corresponding spindle assembly 32 and pressure foot assembly 35.

[0305] Furthermore, the spindle assembly 32 consists of n spindles arranged in an array, the feed assembly 33 consists of n cylinders arranged in an array, and the pressure foot assembly 35 consists of n pressure feet arranged in an array, where n is an even number greater than 0. The number of spindle assemblies 32, feed assemblies 33, and pressure foot assemblies 35 is the same, and each spindle and cylinder is correspondingly arranged with a pressure foot. The cylinders are used to control the extension and retraction of the corresponding spindle and pressure foot. Preferably, a spring 351 is provided between each pressure foot and the first side plate 311 to press the pressure foot against the surface of the perforated acoustic liner panel. Each spring 351 is respectively sleeved on the outer periphery of the spindle. Driven by each cylinder, the pressure foot extends and presses against the surface of the perforated acoustic liner panel under the pressure of the spring, based on the friction between the end face of the pressure foot and the surface of the perforated panel. In this embodiment, the acoustic liner part and the spindle hole-making end actuator 3 are coupled into a whole to improve the rigidity and stability of the hole-making system and reduce vibration during the hole-making process.

[0306] In this embodiment, .

[0307] Furthermore, the multi-spindle hole-making end effector 3 also includes a vacuum tube group 39, which consists of n vacuum tubes arranged in an array. Each vacuum tube is installed on the side of the pressure foot. Based on the principle of vacuum chip removal, the chips generated during the sound liner hole-making process are collected from the pressure foot into a dust collector (not shown in the figure).

[0308] Furthermore, the solenoid valve assembly 34 consists of n+1 solenoid valves arranged in an array, each solenoid valve including two interfaces: an air inlet and an air outlet. Among them, One solenoid valve is used to control the extension and retraction of the cylinders in the cylinder array, and another solenoid valve is used for the spindle air cooling switch control. Preferably, the second side plate 312 is provided with a valve island 341 for installing the solenoid valve group 34. The valve island 341 can achieve independent control of the solenoid valves in the solenoid valve group 34 based on the same air source.

[0309] The ultrasonic sensor group 36 includes four ultrasonic sensors for collision detection, which are evenly distributed and installed at the four corners of the first side plate 311.

[0310] The laser displacement sensor group 37 includes four laser displacement sensors for measuring the deviation between the actual tool coordinate system Z-axis (the axis parallel to the drilling direction) and the ideal tool coordinate system Z-axis. The four laser displacement sensors are evenly distributed at the four corners of the first side plate 311 to provide a basis for end effector attitude correction.

[0311] The vision unit 38 includes a light source to provide good lighting conditions for shooting, and an industrial camera and telecentric lens for measuring the actual position coordinates of the reference holes. The optical axis is parallel to the directions of each spindle on the spindle assembly 32. The light source provides good lighting conditions for shooting, and the industrial camera and telecentric lens measure the actual position coordinates of the reference holes. A hole-making direction deviation measurement system controls the object distance and optical axis direction during industrial camera measurement. After calculating the deviation between the actual positions of multiple reference holes and their corresponding nominal positions, the hole-making positioning error can be calculated based on a certain interpolation compensation strategy, providing a basis for end effector position correction.

[0312] The positioning error measurement method for the multi-spindle end effector 3 is performed according to the following steps:

[0313] SD1 uses a vision unit integrated on the end effector of a robot multi-spindle hole-making system to capture images of reference holes;

[0314] Here, the camera's optical axis is defined as parallel to the axis of the principal array, and the object distance during visual shooting is defined as... and the perpendicularity of the optical axis to the acoustic liner surface The focal distance and the pose of the visual unit when the optical axis is perpendicular to the acoustic liner surface are obtained.

[0315] (D1);

[0316] in:

[0317] Visual unit coordinate system Relative nacelle acoustic liner product coordinate system The position;

[0318] For the calibrated robot base coordinate system Relative to the product coordinate system The position;

[0319] To obtain the robot flange coordinate system based on the robot kinematic model Relative to the robot's base coordinate system The position;

[0320] For the calibrated robot tool coordinate system Relative to the flange coordinate system The position;

[0321] For the already labeled hand-eye relationship, i.e., the visual unit coordinate system Relative to the tool coordinate system The position;

[0322] Indicates the focal distance;

[0323] This indicates that the optical axis is perpendicular to the acoustic liner surface, i.e., the angle is 90°.

[0324] SD2, following SD1, uses a robust, accurate, and efficient benchmark hole feature localization algorithm that integrates visual saliency and mean shift to obtain benchmark hole features in the benchmark hole image. The specific steps are as follows:

[0325] SD21, for the obtained original reference hole image Perform Gaussian filtering or median filtering to obtain the corresponding smoothed image. For smoothed images Perform image contrast stretching to obtain an enhanced image. The saliency of the original reference hole image is calculated according to formula (2). ;

[0326] (D2);

[0327] in:

[0328] This represents the calculation of the average pixel value of an image.

[0329] This indicates that the maximum pixel value of the image is retrieved;

[0330] This indicates that the minimum pixel value of the image is retrieved;

[0331] SD22 selects the saliency map of the reference hole image through region filtering. Obtain the centroid coordinates of the largest salient region in the region. Calculate the coordinates of each pixel position and the centroid coordinates of the saliency map according to formula (D3). Distance map ;

[0332] The weighted graph is calculated according to formula (D4). ;

[0333] According to formula (D5) weight diagram With saliency map Multiplying corresponding elements together removes fragmented salient regions from the salient map, resulting in an updated salient map. ;

[0334] (D3);

[0335] (D4);

[0336] (D5);

[0337] SD23, based on an automatic thresholding method or by selecting a suitable fixed threshold through repeatability testing, updates the saliency map of SD22. Threshold segmentation is performed to segment the reference hole feature region from the saliency map;

[0338] Using edge detection operators or contour extraction algorithms, the baseline hole contour is extracted from the threshold segmentation map of the saliency map. The contour point set is approximately divided into three continuous subsets. Contour points are randomly selected from the three subsets multiple times for circle fitting. The coordinates of the center of all fitted circles are stored in an array.

[0339] From all the candidate centers, one is randomly selected as the initial centroid. Using this as the center, and based on a preset scanning radius, the mean-drift algorithm is used to iteratively find the true centroid of the set of center centers, which serves as the coordinate system for the reference hole center. ;

[0340] SD3 sets the image coordinate system at the image center, with its coordinate axes aligned with the default image coordinate axes. Based on the coordinates of the reference hole center obtained from SD23... Combined with the calibrated intra-visual unit parameters and the known image width and height ;

[0341] The XY plane and its coordinate axes of the visual unit coordinate system are defined to coincide with the coordinate axes of the image coordinate plane and its coordinate system. The physical coordinates of the reference aperture in the visual unit coordinate system are obtained according to formula (D6). ;

[0342] (D6);

[0343] Based on formula (D7) combined with SD1, the following was obtained: The homogeneous transformation matrix of the reference hole in the product coordinate system is obtained. , By rotation matrix Translation vector composition;

[0344] Translation vector The transpose of the coordinates of the reference hole in the product coordinate system obtained by the vision unit measurement is given. ;

[0345] (D7);

[0346] Combining the nominal coordinates of the reference hole in the product coordinate system The hole positioning error at the reference hole is obtained. ;

[0347] (D8);

[0348] SD4. For all reference holes, repeat steps SD1 to SD3 to measure the hole positioning error at all reference holes using a vision system.

[0349] SD5 uses surface interpolation to obtain the hole positioning error at other hole locations within the influence area of ​​the reference hole, and compensates for these errors.

[0350] By adopting the aforementioned design scheme, the beneficial effects of the present invention are as follows: The end effector path planning method for drilling holes in the acoustic liner of aero-engine nacelles of the present invention obtains the shortest movement path of the multi-spindle drilling end effector, which facilitates ensuring the efficiency and processing safety of the acoustic liner hole drilling, thereby shortening the manufacturing cycle of the acoustic liner parts of aero-engine nacelles, and providing a theoretical basis and technical support for specifying the multi-spindle drilling process specifications for aero-engine nacelle acoustic liner robots.

[0351] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for planning the path of the end effector of the acoustic liner hole in an aero-engine nacelle, characterized in that: Follow these steps: S1, through optimization of the equivalent machining hole layout and calculation of the end effector machining pose, k equivalent machining holes are obtained. and its corresponding end effector machining pose parameters; Define the i-th equivalent machined hole The end effector machining pose parameter six-tuple is ; use This indicates the machining sequence of equivalent holes during the hole-making process. Construct the objective function for the equivalent machining hole-making path planning problem. The goal of the plan is to optimize the processing sequence. The state space constituted Find the objective function within. Minimize processing sequence ; （1） in: These are the coordinates of the equivalent machined hole positions. The end effector machining posture is represented by ZXY Euler angles; For the machining sequence of a certain equivalent machining hole At that time, the first and The distance between equivalent machined holes ; The first and The difference in ZXY Euler angles for each equivalent machined hole. , , ; and The weights are set to balance the length of the path and the smoothness of the end effector's machining posture; These are the weighting coefficients for the Euler angle difference of ZXY, respectively; S2, with hole-making path and end effector attitude smoothness weighted sum The reciprocal of this comprehensive evaluation index is the fitness function, and a multi-spindle hole-making path optimization model for the acoustic liner robot of an aero-engine nacelle is established. ; The optimal drilling path is obtained by using a genetic optimization algorithm. ; （2） S3 proposes to initialize the population by selecting individuals and generating an equivalent machining hole processing sequence population size during population initialization. of The number of individuals is multiples of the number of individuals; Will smallest Each individual is initialized as a population individual; Equivalent machining hole layout optimization based on function Given a set of all possible equivalent machined holes with a certain arrangement order, generate a set of equivalent machined holes, including their layout and number of elements, where the machined points of the acoustic liner holes are mutually exclusive and the corresponding machined points of the acoustic liner holes cover the entire hole-making area. This is done by following these steps: SA1 defines the set of all possible equivalent machined holes. Arrange the equivalent machined holes in sequence Chromosomes as part of a genetic algorithm; If the equivalent machining hole arrangement order contain If there are equivalent processing well numbers, then the chromosome is composed of... Each gene is composed of a single gene, and each gene corresponds to an equivalent processing pore layout coordinate. ; in: The x-coordinate of the equivalent machined hole on the plane of the hole-making area is its positional coordinate. This represents the vertical coordinate of the equivalent machined hole on the plane of the hole-making area. Equivalent machined holes defined in tuple form; in: The number of acoustic liner holes machined after positioning the equivalent machining holes. ; , is the set of machining hole points on the plane corresponding to the equivalent machining holes and The set has no more than ; These are the machining points for the acoustic liner holes to be machined, corresponding to each spindle arranged in sequence. The set has fewer than The machining point corresponding to the spindle that does not participate in machining is empty; SA2, perform parameter initialization: set the initial population size for the equivalent machining hole arrangement order as follows. ,and The chromosome length in the equivalence processing pore arrangement order of the population is m; Set the maximum number of iterations. Crossover probability Probability of mutation Interval ratio The initial value; SA3, select all possible equivalent machined holes according to The coordinates are arranged in both sequential and reverse order. These two arrangements are used as two equivalent machining hole arrangement sequences (chromosomes). These two arrangements are then randomly shuffled to generate the remaining sequences. The chromosomes arranged in the equivalent processing pore sequence constitute the initial population of the equivalent processing pore sequence; SA4, calculate the fitness function ; By adopting a greedy selection strategy, based on the set of all possible equivalent machining holes in a certain order, we obtain the set of equivalent machining holes with the smallest number of equivalent machining holes and their layout. （A1）； （A2）； in: Let be a function value of the chromosome representing the equivalent machining hole arrangement order, and be the preferred number of equivalent machining holes, determined by the function. The solution is obtained; This is a preferred set of equivalent machined holes; Coordinates of each element for Layout of intermediate-cost machined holes; SA5 updates each chromosome in the population with equivalent processing pore arrangement by selecting chromosomes with equivalent processing pore arrangement order and by crossover and inversion mutations of genes with equivalent processing pore layout coordinates. After SA6 and SA5, the offspring population will be determined according to the interval ratio. The populations of equivalent machining hole arrangements retained from the parent and offspring generations are recombined to obtain a new population of equivalent machining hole arrangements; SA7, increment the algorithm iteration count by 1 if the algorithm iteration count reaches the maximum iteration count. Enter SA8; Otherwise, return to SA4; SA8 is the equivalent processing hole arrangement sequence chromosome with the best fitness in the population from which the equivalent processing hole arrangement sequence chromosome is output. SA9, initial values ​​for simulated annealing algorithm parameters: The initial temperature is specified as... Set the current temperature Minimum temperature Cooling rate Chain length ; SA10, in the simulated annealing algorithm, creates a new solution for the equivalent machining hole arrangement order based on the inversion mutation factor; SA11, according to The criterion accepts a new solution for the equivalent machining hole arrangement order. The specific process is as follows: [The criterion is then used to] convert the function-based [method / method]... And the arrangement order of equivalent machined holes, and the preferred number of equivalent machined holes. Energy as a solution; SA12, when temperature At this time, the cooling process ends, and it enters SA14; If the current temperature Temperature iteration After that, Return to SA10; SA13, obtained through SA12, yields the minimum energy value in the optimal solution for the equivalent machining hole arrangement sequence. ; SA14, the equivalent machining hole arrangement order corresponding to the minimum energy is the global optimal solution of the genetic-simulated annealing optimization process, and the minimum energy corresponds to... Another output of the function Coordinates of each element For optimal equivalent machining hole layout; The method for generating equivalent machined holes is as follows: SB1 unfolds the curved surface of the nacelle acoustic lining perforation area into a plane, and completes the process according to a certain row spacing and column spacing. Each sound liner hole processing point After arrangement, equivalent machining holes are used. The machining points of the acoustic liner holes are equivalent, and the equivalent machining holes are defined in the form of tuples. ; （B1）； SB2 defines the boundary direction of the bottom surface of the multi-spindle hole-making end effector as being the same as the row and column direction of the acoustic liner holes within the hole-making area; The drilling operation of the multi-spindle drilling end effector is regarded as a sequential scanning operation of the acoustic liner hole machining points. The position of the multi-spindle drilling end effector covering the acoustic liner hole machining points is determined, and thus... One equivalent machining hole and the corresponding set of acoustic liner hole processing points Finally, a set of machining points corresponding to the acoustic liner holes of the equivalent machining holes is obtained. ; （B2）； in: Let S be the position of the set of equivalent machined hole locations in the set S. The set of all equivalent machined holes corresponding to the sound liner holes is a subset of the set S; SB3, under the condition of satisfying formulas (B1) and (B2), generates equivalent machined holes based on a greedy selection strategy, prioritizing the generation of the number of machined holes. Larger equivalent machined holes In the single-positioning machining process of the multi-spindle hole-making end effector, each spindle is fully utilized. The specific steps are as follows: SB31, determined based on the number of spindles in the multi-spindle hole-making end effector. ,make , ; SB32, select the appropriate one according to the current equivalent machining hole sequence. Enter SB33; SB33, if There is Enter SB34; Otherwise Return to SB32; SB34, if ,make , Enter SB35; Otherwise Return to SB32; SB35, if Established and entered SB37; Otherwise proceed to SB36; SB36, Judgment Is it true? If it is true, then... and Enter SB37; Otherwise Enter SB32; SB37 outputs the set of all equivalent machined holes. ; in: This is a set of records of the points that have been processed.

2. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: SA5 uses trigonometric functions to dynamically and nonlinearly adjust the crossover and mutation probabilities based on the fitness function values ​​of each chromosome during the population iteration process according to the equivalent processing hole arrangement order, in order to accelerate the convergence speed of the algorithm.

3. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: In SA11, let ,in Then with a certain probability Accept the new solution, as follows: ； in: The energy of the current optimal solution; The energy for the new solution.

4. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: Define that during the machining of acoustic liner holes in the nacelle, all acoustic liner holes in the drilling area are machined, and the same acoustic liner hole will not be machined repeatedly. Formula (B2) is modified to include the constraint condition of formula (B3). （B3）。 5. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: 。 6. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: The end effector machining pose planning method is performed according to the following steps: SC1, through mapping The simultaneous machining of multiple acoustic liner holes based on a multi-spindle hole-making end effector is mapped to the machining of a single acoustic liner hole based on a single-spindle hole-making end effector. Each sound liner has ; （C1）； in: ( The acoustic liner holes, machined synchronously in a single positioning operation by a multi-spindle end effector, are located in the nacelle acoustic liner product coordinate system. The pose parameters in the middle; These are the coordinates of the acoustic liner hole; for The normal vector of the acoustic lining surface at that location; For the equivalent machined hole coordinate system in the product coordinate system The pose matrix in the middle; SC2 defines that the axis of the acoustic liner hole is collinear with the normal vector of the acoustic liner surface at its location, based on mapping. The normal vector of the acoustic liner hole is used to calculate the equivalent machined hole coordinate system. The shaft, and the specific steps include; SC21, according to the mapping When machining a certain equivalent machining hole, determine the corresponding actual machined acoustic liner hole, and mark the position coordinates of that acoustic liner hole as follows: ; SC22 uses offline programming software to extract the normal vector of the acoustic liner surface at the acoustic liner hole. ; SC23 normalizes the mean value of the normal vector of the actual acoustic liner hole corresponding to the equivalent machined hole, and uses it as the coordinate system of the equivalent machined hole. Axial direction; （C2）； in: The average normal vector of the acoustic liner hole; Equivalent machining hole coordinate system of Axial unit vector; SC3, when mapping Number of medium acoustic liner holes At that time, enter SC4; Mapping Number of medium acoustic liner holes At that time, enter SC5; in: It is a natural number greater than 0; SC4, Set the coordinate system of the equivalent machined hole. Axial direction Simultaneously, based on the design geometric parameters of the end effector spindle array, the origin of the equivalent machining hole coordinate system is calculated. The specific steps include: SC41, based on robot base coordinate system calibration results Obtain the robot's base coordinate system of Negative unit vector in the nacelle acoustic liner product coordinate system Description in ; SC42, and Cross product yields ,Will Unitization As the coordinate system of the equivalent machined hole Axial direction; （C3）； SC43, unit vector and Cross product, yielding the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ; （C4）； SC44, when Establish a coordinate system on the machining plane, and use the coordinates of ... and for shaft and In the axial direction, the coordinates of the equivalent machined hole in this coordinate system are: ,in It depends on the design geometry of the end effector spindle array; SC45, solve for the position coordinates of the origin of the equivalent machined hole coordinate system. ; （C5）； SC5, based on the position coordinates of any two acoustic liner holes, determines the equivalent machined hole coordinate system. The axis direction and origin, and the specific steps include: The SC51 multi-spindle hole-making end effector features parallel spindle axes and flush ends. Machining an equivalent hole can be considered as all hole-making spindles operating on the same machining plane. The machining plane equation is set as follows: [Machining the acoustic liner hole] ; According to SC2, machine the plane. The normal vector is Make the machining plane coefficients in the equation They are respectively equal to The sum of squares of the deviations between the actual acoustic liner hole position coordinates and the fitted plane is calculated using the least squares algorithm. Minimum coefficient ; （C6）； in: Let be the objective function, and let be the optimization model. ; For the first The coordinates of the location of each acoustic liner hole; SC52, Calculate the mapping Coordinates of the position of the middle acoustic liner hole On the machining plane Projection on; （C7）； （C8）； in: For the first The coordinates of the location of each acoustic vent The projection; For the first The coordinates of the location of each acoustic liner hole; SC53, on the machined plane Construct a Cartesian coordinate system in the plane to calculate vectors. and origin Determine the coordinate system for the nacelle acoustic liner product. The equivalent machining hole coordinate system The axis direction and origin, the specific process includes: SC531, according to formula (C7), the first... and The coordinates of the position of each acoustic liner hole are on the machining plane. Projection on and ; SC532, Calculate the machining plane Upward projection Pointing to projection vector And after unitization, we obtain ; SC533, the machining plane obtained by combining formula (C2) unit normal vector We can obtain this through cross product. ; SC534, based on unit vectors and Establish a Cartesian coordinate system ; SC535 can calculate vectors according to formulas (C9) and (C10). and origin ; （C9）； （C10）； in: ; SC536, for vectors Unitization This will serve as the coordinate system for the equivalent machined holes. Axial direction ; SC537, unit vector and Cross product, to obtain the coordinate system of the nacelle acoustic liner product. Equivalent machining hole coordinate system Axial direction ; （C11）； Take the coordinates of one of the acoustic liner holes as the origin, establish a Cartesian coordinate system, and calculate the vector according to the above process. and origin ; SC54, based on the equivalent machining hole coordinate system Axial unit vector and in-situ position coordinates The equivalent machining hole is obtained in the nacelle acoustic liner product coordinate system. pose description matrix Transform it to the robot's base coordinate system This refers to the target machining pose of the multi-spindle end effector. （C12）； （C13）； in: The calibration results for the robot's base coordinate system.

7. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 1, characterized in that: The multi-spindle bore end effector includes an actuator frame, spindle assembly, feed assembly, solenoid valve assembly, and pressure foot assembly; The actuator frame includes a front plate and a rear plate arranged opposite to each other. The spindle assembly, feed assembly and solenoid valve assembly are all arranged in the inner cavity of the actuator frame. The pressure foot assembly is arranged on the rear plate and located outside the actuator frame. The feed assembly is arranged on the rear plate. One end of the spindle assembly is arranged corresponding to the feed assembly, and the other end passes through the front plate and is connected to the pressure foot assembly. The feed assembly is used to control the extension or retraction of the corresponding spindle assembly and pressure foot assembly. It also includes a hole-making position error measurement system for measuring the angle between the hole-making direction of the equivalent machined hole of the multi-spindle hole-making end effector and the normal of the curved surface at the equivalent machined hole on the nacelle acoustic liner. The hole-making position error measurement system includes a laser displacement sensor group installed on the multi-spindle hole-making end effector. The laser displacement sensor group includes four laser displacement sensors for measuring the deviation between the actual tool coordinate system Z-axis and the ideal tool coordinate system Z-axis. The four laser displacement sensors are respectively installed at the four corners of the front plate, and the coordinate system Z-axis is parallel to the hole-making direction. It also includes a hole-making direction deviation measurement system for measuring the position coordinates of pre-made reference holes on the nacelle acoustic liner and calculating the hole-making position error at each reference hole position coordinate. The hole-making direction deviation measurement system includes a vision unit mounted on the multi-spindle hole-making end effector. The vision unit includes a light source for providing good shooting lighting conditions and an industrial camera and telecentric lens for measuring the actual position coordinates of the reference holes. The direction of the light source is parallel to the direction of the spindle assembly.

8. The end effector path planning method for the acoustic liner hole of an aero-engine nacelle according to claim 7, characterized in that: The spindle assembly includes n spindles, the feed assembly includes n cylinders, and the pressure foot includes n pressure feet, where n is an even number greater than 0. Each spindle and cylinder is set up in a one-to-one correspondence with a pressure foot, and each cylinder independently controls the extension and retraction of the corresponding spindle and pressure foot. The solenoid valve assembly includes n+1 solenoid valves, each of which has two interfaces: an air inlet and an air outlet. The n solenoid valves are used to control the extension and retraction of the cylinders, and the other solenoid valve is used for the spindle air cooling switch control. A spring is provided between each presser foot and the front plate to press the presser foot against the surface of the sound liner perforated panel. The spring is correspondingly sleeved on the outer periphery of the spindle. The front panel is also equipped with an ultrasonic sensor group, which includes four ultrasonic sensors for collision detection. The four ultrasonic sensors are installed at the four corners of the front panel.

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