Anisotropic large-scale structure attitude adjustment trajectory planning method

Abstract

The invention provides an anisotropic large-scale structure attitude adjustment trajectory planning method which specifically comprises the following steps: firstly, carrying out dynamic modeling on an attitude adjustment mechanism by adopting a Newton-Euler method so as to calculate driving force of each shaft of a positioner during attitude adjustment of a large-scale structure; dividing the attitude adjustment track into an acceleration section, a constant speed section and a deceleration section, fitting the attitude adjustment track by using a quartic polynomial, and calculating track parameters of the large structure in different directions; and finally, constructing a positioner driving force and speed constraint model, and performing attitude adjustment duration search by adopting a dichotomy, thereby improving the efficiency of attitude adjustment of the large-scale structure. According to the method, different time parameters (the proportion of a constant-speed section) are adopted for planning the motion trails of the large-scale structure in different directions, the performance of a servo control system can be brought into full play, and therefore the attitude adjustment efficiency of the large-scale structure is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of large structure pose adjustment trajectory planning, and in particular to a large structure pose adjustment trajectory planning method with anisotropy. BACKGROUND

[0002] In an automatic assembly system of aerospace large structure, large structure pose adjustment trajectory planning is an important factor affecting the efficiency and stability of large structure pose adjustment. At present, the pose adjustment mechanism for large structure assembly is usually composed of three or more than three positioners, which together with the large structure form a redundant drive parallel pose adjustment mechanism. Since the number of drive shafts of the redundant drive parallel pose adjustment mechanism is greater than the degree of freedom of the end, in order to ensure that the constraint relationship between the drive shafts can still be maintained during the pose adjustment process, the end Cartesian space trajectory planning method needs to be used. Since the motion characteristics of the large structure in different dimensions show obvious anisotropy, in the traditional Cartesian space trajectory planning method, the trajectories of the large structure in different directions are fitted using the same time parameter, which causes the response speed of some dimensions to be forced to be reduced during the adjustment of the attitude of the large structure, greatly affecting the assembly efficiency of the large structure. Therefore, the present application proposes a large structure pose adjustment trajectory planning method with anisotropy, which uses different time parameters to plan the motion trajectories of the large structure in different directions, thereby improving the efficiency of the attitude adjustment of the large structure. SUMMARY

[0003] The purpose of the present application is to provide a large structure pose adjustment trajectory planning method with anisotropy to solve the problems raised in the background. As a specific embodiment, it includes the following steps: first, a dynamics model of the pose adjustment mechanism is established to calculate the driving force of each axis of the positioner; then, a quartic polynomial is used to fit the pose adjustment trajectory and calculate the trajectory parameters of the large structure in different directions; finally, the pose adjustment time is searched under the condition that the motion speed and driving force of the positioner do not exceed a certain threshold, thereby improving the efficiency of the attitude adjustment of the large structure.

[0004] To achieve the above purpose, the present application provides the following technical scheme: a large structure pose adjustment trajectory planning method with anisotropy, comprising the following steps:

[0005] S1: using Newton-Euler method to model the dynamics of the pose adjustment system, calculating the driving force of each axis of the positioner during the adjustment of the attitude of the large structure;

[0006] S2: dividing the pose adjustment trajectory into acceleration segment, constant speed segment and deceleration segment, using a quartic polynomial to fit the motion trajectory of the large structure in the acceleration segment and the deceleration segment, and calculating the trajectory parameters of the large structure in different directions;

[0007] S3: constructing a constraint model of the pose adjustment system and searching for the total pose adjustment time using the bisection method to complete the adjustment of the attitude of the large structure.

[0008] As an improvement, in S1, the specific steps for calculating the driving force of each axis of the positioner are as follows:

[0009] S11: Establish the coordinate system in the large-scale structural attitude adjustment system

[0010] The coordinate system in a large structure attitude adjustment system includes the global coordinate system O. g -xyz and local coordinate system O c -xyz, and equipped with a locator and a ball joint; the ball joint includes a ball head and a ball socket, and the center of the i-th ball joint is the common point of the i-th locator and the large structure, where i = {1,2,3};

[0011] S12: Let the coordinates of the i-th ball joint center in the local coordinate system of the large structure be... At a certain moment, the coordinates of the i-th ball hinge center in the global coordinate system are: Based on the principle of coordinate system transformation, the following equation is obtained:

[0012]

[0013] in, This represents the attitude matrix of the large structure relative to the global coordinate system. Let be the position vector of the large structure relative to the global coordinate system, and their expressions are as follows:

[0014]

[0015] The spatial pose of a large structure relative to the global coordinate system is obtained, represented as a six-dimensional vector w = [αβγx yz]. T The coordinates of the ball joint center in the global coordinate system are adjusted through the coordinated movement of the three positioners. To achieve the change of spatial pose w of a large structure, formula (1) is the kinematic model of the pose adjustment mechanism.

[0016] S13: Constructing a dynamic model for a large structure

[0017] According to Newton's laws, the dynamic equation of a large structure consisting of positioners in the global coordinate system is:

[0018]

[0019] Among them, F i g G represents the force exerted by the i-th locator on the large structure in the global coordinate system. m =[0 0mg] T For the gravity matrix of large components, For the acceleration of a large structure, according to Euler's equations, the angular dynamics equation of the large structure in the local coordinate system is:

[0020]

[0021] In the formula, I is the inertia tensor matrix at the end point. Let be the angular velocity of the large structure relative to its own coordinate system. Angular acceleration;

[0022]

[0023] S14: Constructing the dynamic model of the locator

[0024] In addition to driving the movement of large components, the driving force of the positioner is also used to overcome its own inertial force. The dynamic equation of the positioner is established based on Newton's second law.

[0025] F i d -F i g =M i A i (7)

[0026] In the formula, F i d M i and A i M represents the driving force, inertia coefficient matrix, and acceleration matrix of the i-th positioner, respectively. i and A i The expressions are respectively

[0027]

[0028] in, These represent the masses of the X-axis translation stage, Y-axis translation stage, and Z-axis lifting stage of the i-th locator, respectively. The accelerations output by the i-th positioner along the X, Y, and Z axes;

[0029] S15: Solving for the positioner driving force

[0030] Substituting formula (7) into formulas (4) and (5) yields...

[0031]

[0032] Formula (10) can be written in the form of matrix multiplication.

[0033] H·F D =U (11)

[0034] In the formula

[0035]

[0036] Among them, E 3×3 It is a third-order identity matrix. yes The anti-oblique symmetric matrix can be written in the following form:

[0037]

[0038] Calculate the positioner driving force F D The least 2 norm solution is

[0039]

[0040] Obtain the positioner driving force F D It concerns the spatial pose of a large structure, w = [αβγx yz]. T function

[0041] F D =f FD (w) (17).

[0042] As an improvement, in S1, the global coordinate system O g -xyz is the reference coordinate system within the entire assembly space, with the z-axis perpendicular to the horizontal plane; the local coordinate system O c -xyz is a coordinate system fixed to the large structure itself, which moves with the adjustment of the large structure's own pose, representing the spatial position and attitude of the large structure; and each positioner is connected to the large structure through a ball joint, forming a redundant drive parallel mechanism; the positioner is used to support and adjust the pose of the large component, and has three degrees of freedom: x / y / z. The direction of each axis of the positioner is consistent with the global coordinate system.

[0043] As an improvement, in S2, the specific calculation process for the trajectory parameters of the large structure in all directions is as follows:

[0044] S21: The attitude adjustment trajectory of the large structure is divided into an acceleration phase, a constant velocity phase, and a deceleration phase. The acceleration and deceleration phases require the same amount of time. The trajectory planning principle is that the velocity and acceleration are finite and continuous. A fourth-order polynomial w(t) is used as the trajectory curve for the acceleration and deceleration phases of the large structure.

[0045]

[0046] In the formula, w j (t) represents the trajectory curve of the large structure in the j-th direction, and p0, p1, p2, p3, p4 represent the coefficient vector of the fourth-order polynomial.

[0047] S22: Constructing the constraint equations for attitude adjustment trajectory

[0048] Let the total time for adjusting the attitude of the large structure be t. e The proportions of uniform velocity segments in trajectories of different directions are respectively The initial pose of the large structure is w0, and the target pose is w e The constraint equations for obtaining the attitude adjustment trajectory are as follows:

[0049]

[0050] In the formula, / 2 represents the total duration of the acceleration segment in the j-th direction of the large structure, v j (t) and a j (t) represent the velocity and acceleration curves in the j-th direction of the large structure, respectively, w 0,j and w e,j These represent the j-th elements of the initial pose and target pose of the large structure, respectively, and have...

[0051]

[0052] Where, p b,j Represents the trajectory parameter vector p b The j-th element; b = {0, 1, 2, 3, 4};

[0053] S23: Trajectory Parameter Solving

[0054] make

[0055] Obtain the trajectory parameters p of the large structure b Regarding the total duration t of posture adjustment e The proportion of uniform velocity segments in different trajectories function

[0056]

[0057] As an improvement, the specific search process for the total attitude adjustment time of large structures in S3 is as follows:

[0058] S31: Under the condition of ensuring the stability of the servo system, the velocity V of the positioner at time t. i (t) and driving force F i d If (t) cannot exceed the set threshold, then the constraint model of the attitude adjustment system is:

[0059]

[0060] in,

[0061] Substituting equation (22) into equations (1) and (16) respectively, we obtain the velocity V of the locator at time t. i(t) and driving force F i d (t) represents the total duration t of the posture adjustment. e The proportion of uniform velocity segments in different trajectories The function; V i (t) and F i d (t) is in the following form

[0062]

[0063] S32: Order The constraint model of the attitude adjustment system is as follows:

[0064]

[0065] The conditions for the attitude adjustment system to remain stable are:

[0066]

[0067] Where 1≤n≤18, The duration of the posture adjustment is represented by t. e The proportion of uniform speed segment hour The minimum value; when the attitude adjustment time is t. e At that time, there exists a set Make A value greater than 0 indicates that the current trajectory maintains system stability; A maximum value greater than 0 indicates that the system remains stable. It exists; The maximum value was solved using the particle swarm optimization algorithm, with 60 iterations and a time parameter. The optimization model is

[0068]

[0069] S33: Use the binary search method to perform the attitude adjustment time t e .

[0070] As an improvement, the specific steps for S33 to perform the search are as follows:

[0071] ① Let t e The initial value is like If formula (26) has a solution, then like When formula (26) has no solution, then Until When formula (26) has no solution and When formula (26) has a solution, k = 0;

[0072] ② like If formula (26) has a solution, then otherwise

[0073] ③ Repeat step ② until at this time The particle swarm optimization algorithm optimizes to achieve the minimum pose adjustment time. This represents the proportion of the uniform speed segment in the attitude adjustment trajectory when the attitude adjustment time is the shortest.

[0074] Among the steps This means assigning the value of A to B.

[0075] Beneficial effects: Compared with using the same time parameters (the proportion of the uniform speed segment) Compared with traditional trajectory planning methods that plan trajectories of large structures in different directions, the method of this invention is completely different when planning trajectories of large structures in different directions. It uses different time parameters for planning, which can give full play to the performance of the servo control system and improve the efficiency of attitude adjustment of large structures while ensuring the stability of the servo system. Attached Figure Description

[0076] Figure 1 This is a flowchart illustrating an anisotropic large-scale structure attitude adjustment trajectory planning method proposed in this invention.

[0077] Figure 2 For large-scale structural attitude adjustment systems;

[0078] Figure 3 This is a schematic diagram showing the positioning device and the fit between the ball head and the socket;

[0079] Figure 4 This is a schematic diagram of the velocity trajectory of a large structure.

[0080] In the diagram: 1. Large structure, 2. Ball joint one, 3. Ball joint two, 4. Positioner one, 5. Positioner two, 6. Ball joint three, 7. Positioner three, 8. Ball socket three, 9. Ball head three. Detailed Implementation

[0081] 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.

[0082] The purpose of this invention is to provide a method for planning the attitude adjustment trajectory of anisotropic large structures. Specific implementation methods are described below. Figure 1 As shown, firstly, the dynamic model of the attitude adjustment mechanism is performed to calculate the driving force of each axis of the attitude adjustment mechanism; then, a fourth-order polynomial is used as the trajectory curve to fit the attitude adjustment trajectory, and the trajectory parameters of the large component in different directions are calculated; finally, the attitude adjustment time is searched under the condition that the movement speed and driving force of the positioner do not exceed a certain threshold, thereby improving the efficiency of attitude adjustment of large structures.

[0083] See Figure 2 As shown, in a specific embodiment of the present invention, the large structure attitude adjustment system includes a large structure, three positioners, three ball sockets, three ball heads, and three ball hinges, specifically the large component 1, the first ball hinge 2, the second ball hinge 3, the first positioner 4, the second positioner 5, the third ball hinge 6, and the second positioner 7, wherein each ball hinge consists of a ball head and a ball socket.

[0084] See Figure 2 As shown, the coordinate system in the large structure attitude adjustment system includes a global coordinate system and a large structure local coordinate system. Specifically, the global coordinate system O... g -xyz is the reference coordinate system within the entire assembly space, with its z-axis perpendicular to the horizontal plane; the local coordinate system O for large structures c -xyz is a coordinate system fixed to the large structure 4 itself, which moves as the pose of the large structure 4 is adjusted, representing the position and attitude of the large structure 4.

[0085] See Figure 3 As shown, the positioner has three freedoms: x, y, and z. The directions of each axis of the positioner are consistent with the global coordinate system. The third ball joint 6 includes a third ball socket 8 and a third ball head 9.

[0086] See Figure 4 The figure shows the velocity trajectory curve of the large structure. Specifically, the total time for the attitude adjustment of the large structure is t. e The duration of both the acceleration and deceleration phases is The proportion of the time spent in the constant speed segment is The trajectory curves of the acceleration and deceleration phases are fourth-order polynomials.

[0087] Figure 1 The specific embodiments of the present invention shown include the following steps:

[0088] Step 1: Calculate the driving force of each axis of the positioner, as follows:

[0089] (1) Let the coordinates of the i-th ball hinge center in the local coordinate system of the large structure be expressed as:

[0090] Let i = {1, 2, 3}, and the coordinates of the i-th spherical hinge center in the global coordinate system at a certain moment be expressed as: Based on the principle of coordinate system transformation, the following equation can be obtained.

[0091]

[0092] in, This represents the attitude matrix of the large structure relative to the global coordinate system. Let be the position vector of the large structure relative to the global coordinate system, and its expressions are as follows.

[0093]

[0094] Therefore, the spatial pose of a large structure relative to the global coordinate system can be represented by a six-dimensional vector w = [αβγx yz]. T This indicates that the coordinates r of the ball joint center in the global coordinate system are adjusted through the coordinated movement of the three positioners. i g This can change the spatial pose of a large structure, and formula (1) is the kinematic model of the pose adjustment mechanism.

[0095] (2) According to Newton's laws, the dynamic equation of a large structure consisting of positioners in the global coordinate system is:

[0096]

[0097] Among them, F i g G represents the force exerted by locator i on the large structure in the global coordinate system. m =[0 0mg] T For the gravity matrix of large components, Let be the acceleration of the large structure. According to Euler's equations, the rotational dynamics equation of the large structure in the local coordinate system is:

[0098]

[0099] In the formula, I is the inertia tensor matrix at the end point. Let be the angular velocity of the large structure relative to its own coordinate system. ω is angular acceleration.

[0100]

[0101] (3) The driving force of the positioner is used not only to drive the movement of large components, but also to overcome its own inertial force. The dynamic equation of the positioner is established based on Newton's second law.

[0102] F i d -Fi g =M i A i (7)

[0103] In the formula, F i d M i and A i M represents the driving force, inertia coefficient matrix, and acceleration matrix of positioner i, respectively. i and A i The expressions are respectively

[0104]

[0105] in, Let be the masses of the X-axis translation stage, Y-axis translation stage, and Z-axis lifting stage of the i-th positioner, respectively. The acceleration output of the i-th positioner along the X, Y, and Z axes

[0106] (4) Substituting formula (7) into formulas (4) and (5) yields

[0107]

[0108] Formula (10) can be written in the form of matrix multiplication.

[0109] H·F D =U (11)

[0110] In the formula

[0111]

[0112] Among them, E 3×3 It is a third-order identity matrix. It is r i c The anti-oblique symmetric matrix can be written in the following form:

[0113]

[0114] A smaller driving force can improve the system's control accuracy and motion stability. The positioner driving force F can be calculated. D The least 2 norm solution is

[0115]

[0116] Therefore, the positioner driving force F D It concerns the spatial pose of a large structure, w = [αβγx yz]. T function

[0117] F D =fFD (w) (17)

[0118] Step 2: Calculate the trajectory parameters of the large structure in all directions, as follows:

[0119] (1) The attitude adjustment trajectory of a large structure can be divided into an acceleration segment, a constant speed segment, and a deceleration segment, in which the acceleration segment and the deceleration segment require the same amount of time. The principle of trajectory planning is that the velocity and acceleration are finite and continuous. Therefore, a fourth-order polynomial is used as the trajectory curve for the acceleration and deceleration segments of the large structure.

[0120]

[0121] In the formula, w j (t) represents the trajectory curve of the large structure in the j-th direction.

[0122] (2)S22: Constructing the constraint equations for attitude adjustment trajectory

[0123] Let the total time for adjusting the attitude of the large structure be t. e The proportions of uniform velocity segments in trajectories of different directions are respectively The initial pose of the large structure is w0, and the target pose is w e The constraint equations for obtaining the attitude adjustment trajectory are as follows:

[0124]

[0125] In the formula, / 2 represents the total duration of the acceleration segment in the j-th direction of the large structure, v j (t) and a j (t) represent the velocity and acceleration curves in the j-th direction of the large structure, respectively, w 0,j and w e,j These represent the j-th elements of the initial pose and target pose of the large structure, respectively, and have...

[0126]

[0127] Where, p b,j Represents the trajectory parameter vector p b The j-th element; b = {0, 1, 2, 3, 4};

[0128] S23: Trajectory Parameter Solving

[0129] make

[0130] Therefore, the trajectory parameters p of large structures b It concerns the total posture adjustment time of t. e The proportion of uniform velocity segments in different trajectories The function.

[0131]

[0132] Step 3: Search for the total pose adjustment time, as follows:

[0133] (1) Under the condition of ensuring the stability of the servo system, the velocity V of the positioner at time t. i (t) and driving force F i d If (t) cannot exceed a certain threshold, then the constraint model of the attitude adjustment system is:

[0134]

[0135] in, Substituting formula (22) into formulas (1) and (16), the velocity V of the i-th locator at time t is thus obtained. i (t) and driving force F i d (t) represents the total duration of posture adjustment, t. e The proportion of uniform velocity segments in different trajectories The function. V i (t) and F i d (t) can be written in the following form

[0136]

[0137] (2) Let The constraint model of the attitude adjustment system can then be written in the following form.

[0138]

[0139] Therefore, the condition for the attitude adjustment system to remain stable is

[0140]

[0141] Where 1≤n≤18, The duration of the posture adjustment is represented by t. e The proportion of uniform speed segment hour The minimum value. When the attitude adjustment time is t. e At that time, there exists a set Make A value greater than 0 indicates that the current trajectory can maintain system stability. A maximum value greater than 0 indicates that the system remains stable. Yes, it exists. The maximum value can be solved using the particle swarm optimization algorithm, with 60 iterations and a time parameter. The optimization model is

[0142]

[0143] (3) Posture adjustment time t e The search is performed using a binary search method, and the search steps are as follows:

[0144] ① Let t e The initial value is like If formula (24) has a solution, then like When formula (25) has no solution, then Until When formula (23) has no solution and When formula (25) has a solution, k = 0;

[0145] ② / 2, if If formula (25) has a solution, then otherwise

[0146] ③ Repeat step ② until at this time The particle swarm optimization algorithm optimizes to achieve the minimum pose adjustment time. This represents the proportion of the uniform speed segment in the attitude adjustment trajectory when the attitude adjustment time is shortest.

[0147] In the above steps This means assigning the value of A to B.

[0148] Example

[0149] The coordinates of the ball joint center in the local coordinate system of the large structure are (-310, 451.5, 58.3) mm, (310, 451.5, 58.3) mm, and mm(0, -451.5, 58.3). The mass m of the large structure is 18.1 kg, and the moment of inertia is diag(2.93, 7.15, 4.32) × 10⁻¹⁰. 6 kg·mm 2 The mass of the X-axis translation stage of the locator is 8.3 kg, the mass of the Y-axis translation stage is 7.5 kg, and the mass of the Z-axis lifting stage is 6.9 kg. The maximum operating speed of the locator is (10, 10, 6) mm / s, and the maximum driving force is (150, 150, 300) N. The initial pose w0 of the large structure is (0.212, -0.182, 0.313, 151.5, -162.1, 67.8), and the target pose w0 of the large structure is... e The values ​​are (-0.218, 0.219, -0.132, 250.2, 124.3, 80.7).

[0150] The proportion of uniform speed segments is determined using the particle swarm optimization algorithm. During optimization, the inertia weight ω = 1, the learning factors c1 and c2 are both 0.5, and the total pose adjustment length t e The initial value range is (50, 100). It can be calculated that there exists... make Does not exist make Therefore, in the second iteration, t e The interval is (75, 100). After 9 iterations, the final value of t is... e = 65.3 seconds, When the proportion of uniform velocity segments in different directions is the same for a large structure, the binary search method is also used to search for the minimum attitude adjustment time, and finally t e = 83.7 seconds, Therefore, the anisotropic trajectory planning method proposed in this invention can achieve higher attitude adjustment efficiency.

[0151] The above examples were repeated six times. The initial pose, target pose, and pose adjustment time corresponding to different trajectory planning methods for the large structure in each component example are shown in the table below. It can be found that the anisotropic trajectory planning method proposed in this invention can reduce the pose adjustment time by an average of 20.1%.

[0152] Table 1. Adjustment time of the embodiment

[0153]

[0154]

[0155] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for planning the attitude adjustment trajectory of anisotropic large structures, characterized in that, Includes the following steps: S1: The Newton-Euler method is used to perform dynamic modeling of the attitude adjustment system and to calculate the driving force of each axis of the positioner when the attitude of a large structure is adjusted. S2: Divide the attitude adjustment trajectory into acceleration, constant speed and deceleration segments. Use a fourth-order polynomial to fit the motion trajectory of the large structure in the acceleration and deceleration segments, and calculate the trajectory parameters of the large structure in different directions. S3: Construct a constraint model for the attitude adjustment system and use a bisection method to search for the total attitude adjustment time to complete the attitude adjustment of the large structure.

2. The method for planning the attitude adjustment trajectory of an anisotropic large structure according to claim 1, characterized in that: in S1, the specific steps for calculating the driving force of each axis of the positioner are as follows: S11: Establish the coordinate system in the large-scale structural attitude adjustment system The coordinate system in a large structure attitude adjustment system includes the global coordinate system O. g -xyz and local coordinate system O c -xyz, and equipped with a locator and a ball joint; the ball joint includes a ball head and a ball socket, and the center of the i-th ball joint is the common point of the i-th locator and the large structure, where i = {1,2,3}; S12: Let the coordinates of the i-th ball joint center in the local coordinate system of the large structure be... At a certain moment, the coordinates of the i-th ball hinge center in the global coordinate system are: Based on the principle of coordinate system transformation, the following equation is obtained: in, This represents the attitude matrix of the large structure relative to the global coordinate system. Let be the position vector of the large structure relative to the global coordinate system, and their expressions are as follows: The spatial pose of a large structure relative to the global coordinate system is obtained, represented as a six-dimensional vector w = [αβγx yz]. T The coordinates r of the ball joint center in the global coordinate system are adjusted through the coordinated movement of the three positioners. i g To achieve the change of spatial pose w of large structures, formula (1) is the kinematic model of the pose adjustment mechanism. S13: Constructing a dynamic model for a large structure According to Newton's laws, the dynamic equation of a large structure consisting of positioners in the global coordinate system is: Among them, F i g G represents the force exerted by the i-th locator on the large structure in the global coordinate system. m = [0 0 mg] T For the gravity matrix of large components, For the acceleration of a large structure, according to Euler's equations, the angular dynamics equation of the large structure in the local coordinate system is: In the formula, I is the inertia tensor matrix at the end. Let be the angular velocity of the large structure relative to its own coordinate system. Angular acceleration; S14: Constructing the dynamic model of the locator In addition to driving the movement of large components, the driving force of the positioner is also used to overcome its own inertial force. The dynamic equation of the positioner is established based on Newton's second law. F i d -F i g =M i A i (7) In the formula, F i d M i and A i M represents the driving force, inertia coefficient matrix, and acceleration matrix of the i-th positioner, respectively. i and A i The expressions are respectively in, These represent the masses of the X-axis translation stage, Y-axis translation stage, and Z-axis lifting stage of the i-th locator, respectively. The accelerations output by the i-th positioner along the X, Y, and Z axes; S15: Solving for the positioner driving force Substituting formula (7) into formulas (4) and (5) yields... Formula (10) can be written in the form of matrix multiplication. H·F D =U (11) In the formula Among them, E 3×3 It is a third-order identity matrix. It is r i c The anti-oblique symmetric matrix can be written in the following form: Calculate the positioner driving force F D The least 2 norm solution is Obtain the positioner driving force F D It concerns the spatial pose of a large structure, w = [αβγx yz]. T function F D =f FD (w) (17)。 3. The method for planning the attitude adjustment trajectory of an anisotropic large structure according to claim 2, characterized in that: in S1, wherein, Global coordinate system O g -xyz is the reference coordinate system within the entire assembly space, with the z-axis perpendicular to the horizontal plane; the local coordinate system O c -xyz is a coordinate system fixed to the large structure itself, which moves with the adjustment of the large structure's own pose, representing the spatial position and attitude of the large structure; and each positioner is connected to the large structure through a ball joint, forming a redundant drive parallel mechanism. The positioner is used to support and adjust the pose of large components, and has three degrees of freedom: x, y, and z. The orientation of each axis of the positioner is consistent with the global coordinate system.

4. The method for planning the attitude adjustment trajectory of an anisotropic large structure according to claim 2, characterized in that: in S2, the specific calculation process of the trajectory parameters of the large structure in all directions is as follows: S21: The attitude adjustment trajectory of the large structure is divided into an acceleration phase, a constant velocity phase, and a deceleration phase. The acceleration and deceleration phases require the same amount of time. The trajectory planning principle is that the velocity and acceleration are finite and continuous. A fourth-order polynomial w(t) is used as the trajectory curve for the acceleration and deceleration phases of the large structure. In the formula, w j (t) represents the trajectory curve of the large structure in the j-th direction, and p0, p1, p2, p3, p4 represent the coefficient vector of the fourth-order polynomial. S22: Constructing the constraint equations for attitude adjustment trajectory Let the total time for adjusting the attitude of the large structure be t. e The proportions of uniform velocity segments in trajectories of different directions are respectively The initial pose of the large structure is w0, and the target pose is w e The constraint equations for obtaining the attitude adjustment trajectory are as follows: In the formula, v represents the total duration of the acceleration segment in the j-th direction of the large structure. j (t) and a j (t) represent the velocity and acceleration curves in the j-th direction of the large structure, respectively, w 0,j and w e,j These represent the j-th elements of the initial pose and target pose of the large structure, respectively, and have... in, p b,j Represents the trajectory parameter vector p b The j-th element; b = {0, 1, 2, 3, 4}; S23: Trajectory Parameter Solving make Calculate [p 0,j p 3,j p 4,j ] T =S j -1 D j (21) Obtain the trajectory parameters p of the large structure b Regarding the total duration t of posture adjustment e The proportion of uniform velocity segments in different trajectories function 5. The method for planning the attitude adjustment trajectory of anisotropic large structures according to claim 4, characterized in that: in S3, the specific search process for the total attitude adjustment time of the large structure is as follows: S31: Under the condition of ensuring the stability of the servo system, the velocity V of the positioner at time t. i (t) and driving force F i d If (t) cannot exceed the set threshold, then the constraint model of the attitude adjustment system is: in, Substituting equation (22) into equations (1) and (16) respectively, we obtain the velocity V of the locator at time t. i (t) and driving force F i d (t) represents the total duration t of the posture adjustment. e The proportion of uniform velocity segments in different trajectories The function; V i (t) and F i d (t) is in the following form S32: Order The constraint model of the attitude adjustment system is as follows: The conditions for the attitude adjustment system to remain stable are: Where 1≤n≤18, The duration of the posture adjustment is represented by t. e The proportion of uniform speed segment hour The minimum value; when the attitude adjustment time is t. e At that time, there exists a set Make A value greater than 0 indicates that the current trajectory maintains system stability; A maximum value greater than 0 indicates that the system remains stable. It exists; The maximum value was solved using the particle swarm optimization algorithm, with 60 iterations and a time parameter. The optimization model is S33: Use the binary search method to perform attitude adjustment time t e .

6. The method for planning the attitude adjustment trajectory of an anisotropic large structure according to claim 5, characterized in that: the specific steps of S33 for searching are as follows: ① Let t e The initial value is like If formula (26) has a solution, then like When formula (26) has no solution, then Until When formula (26) has no solution and When formula (26) has a solution, k = 0; ② like If formula (26) has a solution, then otherwise ③ Repeat step ② until at this time The particle swarm optimization algorithm achieves the minimum pose adjustment time. This represents the proportion of the uniform speed segment in the attitude adjustment trajectory when the attitude adjustment time is the shortest. Among the steps This means assigning the value of A to B.

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