A consistent distributed control method for block-based spatial structures

Abstract

The present invention provides a consistent distributed control method for a block-type spatial structure, the method comprising: using the Cardan angle to establish a rotation matrix of a substructure platform, and obtaining a kinematic inverse solution of the substructure platform from the rotation matrix; establishing a transfer matrix between sensor measurement values ​​and actual control quantities based on the structural parameters of a single substructure; describing the posture information transmission relationship between substructures based on the concept of a graph, and judging whether the system can achieve consistency; and constructing a closed-loop control system to achieve consistent distributed control of the postures of multiple substructures.

Description

Technical Field

[0001] The present invention relates to a consistent distributed control method for a block-type spatial structure. Background Art

[0002] The notable feature of large and ultra-large satellite-borne equipment, represented by large-array detection antennas and large deployable optical mirrors, is that the overall structure is usually composed of block-type structures, and the position and posture of each substructure are adjusted individually to meet the high surface accuracy requirements of the spliced ​​overall structure. In order to improve performance indicators such as imaging accuracy, the overall structure size is bound to become larger and larger, and the number of substructures that need to be controlled will increase accordingly. However, traditional centralized control laws are difficult to adapt to such application scenarios with huge structural sizes, numerous system variables, and highly dispersed sensors and actuators. As a result, it is impossible to complete the spatial structure surface adjustment on-orbit within limited time and limited computing power, which ultimately makes it impossible for satellite-borne equipment to complete its established on-orbit mission. Summary of the Invention

[0003] Purpose of the invention: In order to solve the problem of distributed coordination of multiple substructures in the existing technology when performing surface control on block-spliced ​​spatial structures of large-array detection antennas and large-scale deployable optical mirrors, the present invention provides a consistent distributed control method for block-type spatial structures, which can maintain good surface accuracy of the overall structure through distributed sensing and control of substructures.

[0004] The method of the present invention comprises the following steps:

[0005] Step 1: Establish a six-degree-of-freedom substructure parallel platform system;

[0006] Step 2, solving the control problem of the six-degree-of-freedom substructure parallel platform system;

[0007] Step 3: Based on the results of step 2, the six-degree-of-freedom substructure parallel platform system is controlled.

[0008] In step 1, the six-degree-of-freedom substructure parallel platform system is composed of block-type substructure platforms. Each substructure platform serves as a load-bearing object and is supported by six actuator rods arranged in parallel. The actuator rods are connected to the substructure platform and the base through ball joints at the upper and lower parts, respectively, to form a 6-SPS Stewart platform. The substructure platform can move in six degrees of freedom in space by controlling the output displacement of the actuator. The adjacent substructure platforms communicate with each other through edge sensors, so that the posture of the entire six-degree-of-freedom substructure parallel platform system is consistent and reaches the expected target posture.

[0009] In step 2, for the six-degree-of-freedom substructure parallel platform system, the actuator rod is defined to be connected to the substructure platform through a spherical joint A, and the i-th hinge point is Ai , i=1,2,3; the actuator is connected to the base through a spherical joint B, and the i-th hinge point is B i ;

[0010] The coordinate systems and parameters are defined as follows: the dynamic coordinate system O′x′y′z′ is fixed to the substructure platform, the static coordinate system Oxyz is fixed to the base, and both O and O′ are located at the geometric center of the triangle formed by the hinge point;

[0011] The coordinate of the substructure platform center O′ in the static coordinate system is marked as [O′ x ,O′ y ,O′ z ] T The Cardan angles of the substructure platform rotating around the x-axis, y-axis and z-axis of the static coordinate system are denoted as a, b and g respectively, and the length of the actuator rod is denoted as d i , i=1,2...,6;

[0012] The adjacency matrix of the system communication graph is recorded as n ij Represents the element in the i-th row and j-th column of the matrix N. The Laplacian matrix is ​​recorded as l ij Represents the element in the i-th row and j-th column of the matrix L; is an N×N dimensional real matrix.

[0013] In step 2, the Cardan angles a, b, and g are used to describe the posture of the substructure platform, and the rotation matrix Rot of the substructure platform is obtained:

[0014]

[0015] Hinge Point A i The coordinate of the moving axis is marked as A′ i =[x′ ai y′ ai z′ ai ] T , where x′ ai y′ ai z′ ai The hinge point A i The coordinate values ​​on the x', y' and z' axes in the moving coordinate system, the superscript T is the transposition symbol; correspondingly, the hinge point A i The meditation is marked as A i =[x ai y ai z ai ] T , where x ai y ai z ai The hinge point A iThe coordinate values ​​on the x-axis, y-axis and z-axis in the static coordinate system;

[0016] The hinge point A is rotated by the rotation matrix Rot i The moving coordinate A′ i Transform to static coordinate A i :

[0017] A i =Rot·A′ i +[xyz] T (2)

[0018] The hinge point B i The static coordinate is represented by B i =[x bi y bi z bi ] T , where x bi y bi z bi Hinge point B i The coordinate values ​​on the x-axis, y-axis and z-axis in the static coordinate system;

[0019] Then the length vector d of the actuator in the static coordinate system is i Expressed as:

[0020] d i =A i -B i (3)

[0021] The magnitude of the rod length vector is:

[0022]

[0023] Step 2 also includes: establishing a transfer matrix: reading the relative positions between adjacent substructure platforms through edge sensors;

[0024] Edge Sensor S j Two sensors are placed in a group on two adjacent substructures, j = 1, 2, ..., 12; two sensors are placed on each side of each substructure, and are symmetrical about the midline of the substructure edge. The distance between the two sensors is (a-2f), where a is the length of the substructure side and f is the distance from the sensor to the nearest substructure vertex; the distance from the end of each edge sensor to the edge of the substructure is g; h is the distance between the three hinge points A on the substructure. i The height of the equilateral triangle, i = 1, 2, 3;

[0025] Let hinge point A i The z-axis increment at is Δz i , when the substructure platform rotates around the straight line passing through the other two hinge points, the edge sensor S jThe reading increment Δs at j for:

[0026]

[0027] where r ji For edge sensor S j To the hinge point A i The distance of the determined axis of rotation; if the z-axis increment Δz1 exists only at the hinge point A1, then the geometric relationship yields:

[0028]

[0029] The following relationship is obtained from the symmetry of the structure:

[0030]

[0031] Step 2 also includes: defining the control matrix element C ji Hinge point A i When the z-axis increment of 1 μm is generated at the edge sensor S j The reading increment is:

[0032] C ji =r ji / h (8)

[0033] Thus, the sensor reading increment Δs is obtained j and the z-axis increment Δz at the hinge point i Relationship:

[0034]

[0035] In formula (9), i = 1, 2, 3, j = 1, 2, ..., 12;

[0036] By controlling the matrix C = [C ji ] Take the pseudo-inverse to get the matrix U = [U ij ],U ij Represents the element in the i-th row and j-th column of the matrix U, and obtains the z-axis increment Δz at the hinge point i and sensor reading increment Δs j Relationship:

[0037]

[0038] Step 2 also includes: establishing the following system communication topology: considering a structure array consisting of 7 six-degree-of-freedom substructures, 1 to 7 are substructure platform numbers, R is the distribution circle radius of substructure platforms 1 to 6, and γ is the gap between substructure platforms;

[0039] Taking the origin O of the static coordinate system of substructure platform No. 7 as the origin, establish the coordinate system OXYZ to describe the positional relationship of the substructure platforms. The Y axis is perpendicular to one side of the hexagon, the X axis is perpendicular to the Y axis and passes through the vertex of the hexagon, and the Z axis is perpendicular to the OXY plane, forming a right-handed system. The initial position coordinates of the center points of each substructure platform are written as:

[0040] [Rcos(60°·i-30°) Rsin(60°·i-30°) H] T (11)

[0041] Where i = 1, 2, ..., 6, H is the initial height of the substructure platform, and T represents the matrix transpose.

[0042] Step 2 also includes: when consistent distributed control is adopted, substructure platform No. 7 is set as the single leader, and the topological structure of the system communication relationship is described using the concept of a graph, that is, each substructure is represented by a circle, and the communication relationship between substructures is indicated by an arrow.

[0043] Step 2 also includes: based on the system communication topology, determining whether the system can achieve global consistency according to the following theorem:

[0044] Theorem 1: For a controlled multi-agent network with an arbitrary topology, global consensus can be achieved if L + Ω is non-singular and one of the following conditions holds:

[0045] Condition 1: L+Ω is an M matrix;

[0046] Condition 2:

[0047] Where L is the Laplacian matrix of the graph; Ω is a diagonal matrix, Ω = diag(w1…w N ), whose diagonal elements ω i Defined as: when the i-th agent is the leader w i =1, i=1,2,...N; Re represents the real part of the complex number, l i (L+Ω) represents the i-th eigenvalue of the matrix (L+Ω);

[0048] For a system using consistent distributed control, the leader acts as a benchmark and does not accept information from other substructures. The leader and followers are connected by single arrows. Followers communicate with adjacent followers and are connected by double-headed arrows. The adjacency matrix N is:

[0049]

[0050] The Laplacian matrix L is:

[0051]

[0052] There is only one leader, so there are:

[0053]

[0054] The matrix L+Ω is found to be a non-singular matrix, and Theorem 1 is satisfied, that is, the system based on consistent distributed control can achieve global consistency.

[0055] Step 3 includes:

[0056] Initially, the substructure platform is aligned and the edge sensor readings are calibrated to determine the zero point. Afterwards, the substructure platform is subjected to external disturbances and deviations occur, causing the sensor readings to change. The sensor reading increment is solved as the required adjustment amount at the hinge point by formula (10) in step 2. The hinge point adjustment amount is then used to determine the actuator adjustment amount of the parallel structure. After the actuator makes the corresponding adjustment, the substructure platform posture is updated. The sensor reads again, thus forming a closed-loop control.

[0057] When the method described in steps 1 to 3 is performed, the shape and surface control of the block-type spatial structure is achieved.

[0058] The present invention has the following beneficial effects:

[0059] (1) Distributed control reduces the computational load of a single control system and increases the overall scale limit;

[0060] (2) Modular structure facilitates system expansion;

[0061] (3) The substructures serve as references to each other, improving the overall accuracy;

[0062] (4) When the system scale is large, the control response is faster. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent.

[0064] Figure 1 It is a schematic diagram of the six-degree-of-freedom substructure array.

[0065] Figure 2 It is a schematic diagram of the six-degree-of-freedom substructure model.

[0066] Figure 3 is the edge sensor layout diagram.

[0067] Figure 4 This is a top view of the six-degree-of-freedom substructure array.

[0068] Figure 5 It is a system communication relationship diagram.

[0069] Figure 6 It is the system control flow chart.

[0070] Figure 7a It is a schematic diagram of the response curve of the substructure platform's translational freedom in the x-axis direction.

[0071] Figure 7b It is a schematic diagram of the response curve of the substructure platform's translational freedom in the y-axis direction.

[0072] Figure 7c It is a schematic diagram of the response curve of the substructure platform's translational freedom in the z-axis direction.

[0073] Figure 7d It is a schematic diagram of the response curve of the substructure platform's rotational freedom around the x-axis.

[0074] Figure 7e It is a schematic diagram of the response curve of the substructure platform's rotational freedom around the y-axis.

[0075] Figure 7f It is a schematic diagram of the response curve of the substructure platform's rotational freedom around the z-axis. DETAILED DESCRIPTION

[0076] The present invention provides a consistent distributed control method for a block-type spatial structure. The present invention is directed to a six-degree-of-freedom substructure parallel platform system, and its structural diagram is as follows: Figure 1 As shown. Each substructure platform serves as a bearing object and is supported by six actuator rods arranged in parallel. The actuator rods are connected to the substructure platform and the base through ball joints at the top and bottom, respectively, to form a 6-SPS Stewart platform. The substructure platform can achieve six degrees of freedom in space by controlling the output displacement of the actuator. Adjacent substructures communicate with each other through edge sensors to achieve posture information consistency of the entire structural system and achieve the expected target posture, meeting the requirements of high surface accuracy. In addition, the present invention focuses on the kinematic and control problems of multi-substructure systems. The specific steps of the invention are described as follows:

[0077] (1) For Figure 2 The six-degree-of-freedom substructure model shown in the figure defines that the actuator rod is connected to the substructure platform through a spherical joint A, and the i-th hinge point is A i , i=1,2,3; the actuator is connected to the base through a spherical joint B, and the i-th hinge point is B iThe coordinate system and parameters are defined as follows: the dynamic coordinate system O′x′y′z′ is fixed to the substructure platform, the static coordinate system Oxyz is fixed to the base, and both O and O′ are located at the geometric center of the triangle formed by the hinge. The coordinate of the substructure platform center O′ in the static coordinate system is marked as [O′ x ,O′ y ,O′ z ] T The Cardan angles of the substructure platform rotating around the x, y and z axes of the static coordinate system are denoted as a, b, and g respectively, and the length of the actuator rod is denoted as d i (i=1,2...,6). The adjacency matrix of the system communication graph is recorded as The Laplacian matrix is ​​denoted as

[0078] (2) Using the Cardan angles a, b, and g to describe the posture of the substructure platform, the rotation matrix of the substructure platform is obtained:

[0079]

[0080] (3) Use the rotation matrix Rot to move the hinge point A i The moving coordinate A′ i =[x′ ai y′ ai z′ ai ] T Transform to static coordinate A i =[x ai y ai z ai ] T :

[0081] A i =Rot·A′ i +[xyz] T (2)

[0082] The hinge point B i The static coordinate is represented by B i =[x bi y bi z bi ] T , then the length vector d of the actuator in the static coordinate system is i Expressed as:

[0083] d i =A i -B i (3)

[0084] It can be seen that the modulus of the rod length vector is:

[0085]

[0086] (4) Transfer matrix

[0087] The relative positions between adjacent substructures are read by edge sensors. The edge sensor layout and related parameters are as follows: Figure 3 shown.

[0088] Among them: A i (i=1,2,3) is the hinge position where the actuator is connected to the substructure platform;

[0089] S j (j=1, 2, ..., 12) are edge sensors arranged on the substructure platform;

[0090] a is the side length of the hexagonal substructure platform;

[0091] f is the distance from the edge sensor to the nearest platform vertex;

[0092] g is the edge sensor size parameter;

[0093] h is the height of the equilateral triangle formed by the three hinge points.

[0094] Considering that the rotation angle of the substructure platform is small, let the hinge point A i The z-axis increment at is Δz i , the substructure platform rotates linearly around the other two hinge points, then the edge sensor S j The reading increment Δs at j Expressed as:

[0095]

[0096] where r ji For sensor S j To the hinge point A i The vertical distance of the rotation axis. If the z-axis increment z1 exists only at the hinge point A1, then Figure 3 The parameters a, h, g, and f in are calculated as follows:

[0097]

[0098] The following relationship is obtained from the symmetry of the structure:

[0099]

[0100] It can be verified that formula (6) satisfies the closed relationship.

[0101] (5) Define the control matrix element C ji Hinge point A i When the z-axis increment of 1um is generated at the sensor S j The reading increment is:

[0102] C ji =r ji / h (8)

[0103] Thus, the sensor reading increment Δs is obtained j and the z-axis increment Δz at the hinge point i Relationship:

[0104]

[0105] By controlling the matrix C = [C ji ] Take the pseudo-inverse to get the matrix U = [U ij ], and get the z-axis increment Δz at the hinge point i and sensor reading increment Δs j Relationship:

[0106]

[0107] Consider a structure array consisting of seven six-degree-of-freedom substructures, Figure 4 A top view of the structure array.

[0108] In the figure, 1 to 7 are substructure numbers, R is the radius of the distribution circle for substructures 1 to 6, and γ is the gap between the substructure platforms. With the origin O of the static coordinate system of substructure 7 as the origin, a coordinate system OXYZ (with the Z axis perpendicular to the plane and forming a right-handed system) is established to describe the positional relationship of the substructures. The initial position coordinates of the center points of each substructure platform are then written as:

[0109] [Rcos(60°·i-30°) Rsin(60°·i-30°) H] T ,(i=1,2...,6) (11)

[0110] Where H is the initial height of the substructure platform.

[0111] (7) When using consistent distributed control, set substructure 7 as the single leader. Use the concept of graph to describe the topology of the system communication relationship, such as Figure 5 As shown;

[0112] (8) Based on the system communication topology in step 6, determine whether it can achieve global consistency of the system according to the following theorem:

[0113] Theorem 1 For a controlled multi-agent network with an arbitrary topology, global consensus can be achieved if L + Ω is non-singular and one of the following conditions holds:

[0114] Condition 1: L+Ω is an M matrix;

[0115] Condition 2:

[0116] Where Ω=diag(w1...w N ), when the Nth agent is the leader w N =1.

[0117] (9) For systems using consistent distributed control, based on Figure 5 The system communication relationship diagram shown in the figure, the adjacency matrix is:

[0118]

[0119] The Laplacian matrix is:

[0120]

[0121] There is only one leader, so there are:

[0122]

[0123] The matrix L+Ω is found to be a non-singular matrix, and Theorem 1 is satisfied, that is, the system based on consistent distributed control can achieve global consistency.

[0124] (10) Construct a system control flow chart, such as Figure 6 As shown, the following steps are included:

[0125] The sensor parameters of the acquirer are obtained. According to the pose reference value and disturbance, the hinge adjustment amount is calculated from the sensor reading, the actuator adjustment amount is calculated from the hinge adjustment amount, and the substructure pose is updated by the actuator.

[0126] Example

[0127] This embodiment verifies the effectiveness of the proposed control method through the following examples.

[0128] for Figure 2 The six-degree-of-freedom substructure model setting parameters are:

[0129]

[0130] The position coordinates of the substructure platform center in the static coordinate system [xyz] T Cardan angle relative to the static coordinate axis of the substructure platform [abg] T To describe the posture of the substructure platform [xyzabg] T .

[0131] for Figure 3The substructure platform model setting parameters are: a=900mm, h=706mm, g=55mm, f=173mm. Figure 4 In the substructure array diagram shown, the parameters are set as R = 1600mm, g = 41.2mm, and H = 600mm. The initial position of each substructure platform is P i :

[0132] P i =[Rcos(60°·i-30°) Rsin(60°·i-30°) H 0 0 0] T ,(i=1,2...,6) (16)

[0133] On this basis, increase the disturbance ΔP i :

[0134] ΔP i =[10 10 10 1° 1° 1°] T ·rand(-1,1),(i=1,2...,6) (17)

[0135] Where rand(-1,1) means taking a random value between -1 and 1.

[0136] Set the pose of substructure platform No. 7 as the target pose:

[0137] P7=[0 0 H rand(-1,1) rand(-1,1) 0] T (18)

[0138] According to the above parameters, refer to Figure 5 The communication relationship shown in FIG. 1 is simulated using MATLAB software. The control method proposed in the present invention can realize the consistent distributed control of the system, and the following is obtained: Figure 7a 、 Figure 7b 、 Figure 7c 、 Figure 7d 、 Figure 7e 、 Figure 7f The substructure posture adjustment process is shown in the figure. It can be seen from the figure that under the control method used, the substructure can reach the desired posture.

[0139] The present invention provides a consistent distributed control method for block-based spatial structures. There are numerous methods and approaches for implementing this technical solution. The above is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the present invention. Any components not specified in this embodiment may be implemented using existing technologies.

Claims

1. A consistent distributed control method for a block-type spatial structure, characterized in that: The following steps are involved: Step 1: Establish a six-degree-of-freedom substructure parallel platform system; Step 2, solving the control problem of the six-degree-of-freedom substructure parallel platform system; specifically, for the six-degree-of-freedom substructure parallel platform system, defining the actuator rod and the substructure platform to be connected via a spherical joint A; using the Cardan angles a, b, and g to describe the substructure platform posture, and obtaining the rotation matrix of the substructure platform; establishing a transfer matrix; defining the control matrix element C ji Hinge point A i When the z-axis increment of 1 μm is generated at the edge sensor S j The reading increment is: establish the system communication topology; use the concept of graph to describe the topology of the system communication relationship; based on the system communication topology, determine whether the system can achieve global consistency; Step 3: Based on the result of step 2, the six-degree-of-freedom substructure parallel platform system is controlled; In step 1, the six-degree-of-freedom substructure parallel platform system is composed of block-type substructure platforms. Each substructure platform serves as a load-bearing object and is supported by six actuator rods arranged in parallel. The actuator rods are connected to the substructure platform and the base through ball joints at the upper and lower parts, respectively, to form a 6-SPS Stewart platform. The substructure platform can move in six degrees of freedom in space by controlling the output displacement of the actuator. The adjacent substructure platforms communicate with each other through edge sensors, so that the posture of the entire six-degree-of-freedom substructure parallel platform system is consistent and reaches the expected target posture.

2. The method according to claim 1, characterized in that In step 2, for the six-degree-of-freedom substructure parallel platform system, the actuator rod is defined to be connected to the substructure platform through a spherical joint A, and the i-th hinge point is A i , i=1,2,3; the actuator is connected to the base through a spherical joint B, and the i-th hinge point is B i ; The coordinate systems and parameters are defined as follows: the dynamic coordinate system O′x′y′z′ is fixed to the substructure platform, the static coordinate system Oxyz is fixed to the base, and both O and O′ are located at the geometric center of the triangle formed by the hinge point; The coordinate of the substructure platform center O′ in the static coordinate system is marked as [O x ′,O y ′,O z ′] T The Cardan angles of the substructure platform rotating around the x-axis, y-axis and z-axis of the static coordinate system are denoted as a, b and g respectively, and the length of the actuator rod is denoted as d i , i=1,2...,6; The adjacency matrix of the system communication graph is recorded as n ij Represents the element in the i-th row and j-th column of the matrix N. The Laplacian matrix is ​​recorded as l ij Represents the element in the i-th row and j-th column of the matrix L; is an N×N dimensional real matrix.

3. The method according to claim 2, characterized in that In step 2, the Cardan angles a, b, and g are used to describe the posture of the substructure platform, and the rotation matrix Rot of the substructure platform is obtained: Hinge Point A i The coordinate of the moving axis is marked as A′ i =[x′ ai y′ ai z′ ai ] T , where x′ ai y′ ai z′ ai The hinge point A i The coordinate values ​​on the x', y' and z' axes in the moving coordinate system, the superscript T is the transposition symbol; correspondingly, the hinge point A i The meditation is marked as A i =[x ai y ai z ai ] T , where x ai y ai z ai Hinge point A i The coordinate values ​​on the x-axis, y-axis and z-axis in the static coordinate system; The hinge point A is rotated by the rotation matrix Rot i The moving coordinate A i ' is transformed into static coordinate A i : TO i =Rot·A i ′+[xyz] T (2) The hinge point B i The static coordinate is represented by B i =[x bi y bi z bi ] T , where x bi y bi z bi Hinge point B i The coordinate values ​​on the x-axis, y-axis and z-axis in the static coordinate system; Then the length vector d of the actuator in the static coordinate system is i Expressed as: d i =A i -B i (3) The magnitude of the rod length vector is:

4. The method according to claim 3, characterized in that Step 2 also includes: establishing a transfer matrix: reading the relative positions between adjacent substructure platforms through edge sensors; Edge Sensor S j Two sensors are placed in a group on two adjacent substructures, j = 1, 2, ..., 12; two sensors are placed on each side of each substructure, and are symmetrical about the midline of the substructure edge. The distance between the two sensors is (a-2f), where a is the length of the substructure side and f is the distance from the sensor to the nearest substructure vertex; the distance from the end of each edge sensor to the edge of the substructure is g; h is the distance between the three hinge points A on the substructure. i The height of the equilateral triangle, i = 1, 2, 3; Let hinge point A i The z-axis increment at is Δz i , when the substructure platform rotates around the straight line passing through the other two hinge points, the edge sensor S j The reading increment Δs at j for: where r ji For edge sensor S j To the hinge point A i The distance of the determined axis of rotation; if the z-axis increment Δz1 exists only at the hinge point A1, then the geometric relationship yields: The following relationship is obtained from the symmetry of the structure:

5. The method according to claim 4, characterized in that Step 2 also includes: defining the control matrix element C ji Hinge point A i When the z-axis increment of 1 μm is generated at the edge sensor S j The reading increment is: C ji =r ji / h (8) Thus, the sensor reading increment Δs is obtained j and the z-axis increment Δz at the hinge point i Relationship: In formula (9), i = 1, 2, 3, j = 1, 2, ..., 12; By controlling the matrix C = [C ji ] Take the pseudo-inverse to get the matrix U = [U ij ],U ij Represents the element in the i-th row and j-th column of the matrix U, and obtains the z-axis increment Δz at the hinge point i and sensor reading increment Δs j Relationship:

6. The method according to claim 5, characterized in that Step 2 also includes: establishing the following system communication topology: considering a structure array consisting of 7 six-degree-of-freedom substructures, 1 to 7 are substructure platform numbers, R is the distribution circle radius of substructure platforms 1 to 6, and γ is the gap between substructure platforms; Taking the origin O of the static coordinate system of substructure platform No. 7 as the origin, establish the coordinate system OXYZ to describe the positional relationship of the substructure platforms. The Y axis is perpendicular to one side of the hexagon, the X axis is perpendicular to the Y axis and passes through the vertex of the hexagon, and the Z axis is perpendicular to the OXY plane, forming a right-handed system. The initial position coordinates of the center points of each substructure platform are written as: [Rcos(60°·i-30°)Rsin(60°·i-30°)H] T (11) Where i = 1, 2, ..., 6, H is the initial height of the substructure platform, and T represents the matrix transpose.

7. The method according to claim 6, characterized in that Step 2 also includes: when consistent distributed control is adopted, substructure platform No. 7 is set as the single leader, and the topological structure of the system communication relationship is described using the concept of a graph, that is, each substructure is represented by a circle, and the communication relationship between substructures is indicated by an arrow.

8. The method according to claim 7, characterized in that Step 2 also includes: based on the system communication topology, determining whether the system can achieve global consistency according to the following theorem: Theorem 1: For a controlled multi-agent network with an arbitrary topology, global consensus can be achieved if L + Ω is non-singular and one of the following conditions holds: Condition 1: L+Ω is an M matrix; Condition 2: Where L is the Laplacian matrix of the graph; Ω is a diagonal matrix, Ω=diag(ω1...ω N ), whose diagonal elements ω i Defined as: When the i-th agent is the leader, ω i =1, i=1,2,...N; Re represents the real part of the complex number, λ i (L+Ω) represents the i-th eigenvalue of the matrix (L+Ω); For a system using consistent distributed control, the leader, as a benchmark, does not accept information from other substructures. The leader and followers are connected by single arrows. Followers communicate with adjacent followers, and followers are connected with adjacent followers by double-headed arrows. The adjacency matrix N is: The Laplacian matrix L is: There is only one leader, so there are: The matrix L+Ω is found to be a non-singular matrix, and Theorem 1 is satisfied, that is, the system based on consistent distributed control can achieve global consistency.

9. The method according to claim 8, characterized in that Step 3 includes: Initially, the substructure platform is aligned and the edge sensor readings are calibrated to determine the zero point. Afterwards, the substructure platform is subjected to external disturbances and deviations occur, causing the sensor readings to change. The sensor reading increment is solved as the required adjustment amount at the hinge point by formula (10) in step 2. The hinge point adjustment amount is then used to determine the actuator adjustment amount of the parallel structure. After the actuator makes the corresponding adjustment, the substructure platform posture is updated. The sensor reads again, thus forming a closed-loop control. When the method described in steps 1 to 3 is performed, the shape and surface control of the block-type spatial structure is achieved.

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