A method and system for controlling the position of an airbag supporting a flexible raft vibration isolation system

Abstract

This invention belongs to the field of vibration reduction and noise reduction technology for surface ships and underwater vehicles. It discloses a method and system for attitude control of an airbag-supported flexible floating raft vibration isolation system. The method includes: obtaining the actual observation positions of multiple measuring points on the raft frame; using iterative reweighted least squares fitting to obtain a reference plane for the raft frame based on the actual observation positions; obtaining the rigid body displacements corresponding to the measuring points based on the reference plane, and obtaining the elastic deformation displacements corresponding to the measuring points based on the actual observation positions and rigid body displacements, thereby obtaining the rigid body displacements and elastic deformation displacements corresponding to the airbags; constructing an index system based on the rigid body displacements, elastic deformation displacements, and pressure corresponding to the airbags, and determining the airbags to be adjusted based on the index system. This invention achieves a more suitable reference plane for new installation processes and approximately separates the rigid body displacements and elastic deformation displacements of the raft frame, providing more comprehensive indicators and improving the accuracy of airbag selection.

Description

Technical Field

[0001] This invention belongs to the technical field of vibration reduction and noise reduction for surface ships and underwater vehicles, and more specifically, relates to a posture control method and system for an airbag-supported flexible floating raft vibration isolation system. Background Technology

[0002] With the development of vibration isolation technology, applying airbag vibration isolation technology to floating raft devices can significantly attenuate the transmission of equipment vibration to the hull, thus significantly improving the vibration isolation effect. However, as floating raft structures become larger, their stiffness inevitably decreases. Due to factors such as uneven weight distribution of equipment on the raft frame, equipment start-up and shutdown, slow airbag leakage, and external disturbances, the raft frame will undergo significant elastic deformation, making it difficult to maintain a stable equilibrium posture. This results in uneven stress on connecting pipelines, leading to a reduction in vibration isolation effectiveness and even threatening the safety of equipment and pipelines. Therefore, to achieve high-precision raft frame posture control while considering the elastic deformation of the raft frame, appropriate strategies are needed to accurately select the airbags and their inflation and deflation, and to rationally design control strategies.

[0003] In existing technologies, the reference plane of the raft is usually determined by the readings of displacement sensors at the four corners of the raft, and the displacement of the airbag supporting the raft is determined. The airbag to be adjusted is determined by combining the pressure and displacement parameters of the airbag. However, the determination of the reference plane is not comprehensive enough and does not fit the new installation process of the raft. Furthermore, the elastic deformation factor of the raft is not considered in the selection of the airbag to be adjusted, and the selection criteria for the airbag are relatively limited.

[0004] Furthermore, the selection of airbags is typically based on the direct multiplication of various parameters, resulting in an unclear physical meaning in the selection process. The control strategy does not incorporate feedback correction based on the actual adjustment effect, leading to a significant discrepancy between the expected and actual adjustment effects, thus impacting the raft attitude control. Therefore, existing technologies are insufficient in terms of airbag selection accuracy, and the control strategy design is inadequate. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides a posture control method and system for an airbag-supported flexible floating raft vibration isolation system. This method addresses the problem that the selection of the airbag to be adjusted in the existing airbag-supported flexible floating raft vibration isolation system does not take into account the elastic deformation factor of the raft frame, and the airbag selection index is relatively limited, resulting in insufficient accuracy in airbag selection.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for position control of an airbag-supported flexible floating raft vibration isolation system is provided, wherein the flexible floating raft vibration isolation system includes a raft frame supported on a plurality of airbags, and the position control method includes:

[0007] Obtain the actual observation positions of multiple preset measuring points on the raft frame, wherein the multiple measuring points include at least a plurality of points that are set up one-to-one with the airbag;

[0008] Based on the actual observation positions of multiple measuring points, the reference plane of the raft is obtained by fitting using the iterative reweighted least squares method; wherein, in the iterative reweighted least squares method, the error of the measuring point is obtained based on the deviation between the actual observation position of the measuring point and its position on the reference plane, and an error weight is assigned to the error of each measuring point, with the optimization objective being to minimize the weighted sum of the errors of multiple measuring points;

[0009] Based on the positional distance between the measuring points on the reference plane and the ideal pose plane, the rigid body displacement corresponding to the measuring points is obtained, and the elastic deformation displacement corresponding to the measuring points is obtained according to the actual observation position and the rigid body displacement, thereby obtaining the rigid body displacement and elastic deformation displacement corresponding to the airbag.

[0010] An index system is constructed based on the rigid body displacement, elastic deformation displacement, and pressure corresponding to the airbag. Based on the index system, the airbag to be adjusted is determined and its position and posture are controlled.

[0011] According to another aspect of the present invention, a posture control system for an airbag-supported flexible floating raft vibration isolation system is provided. The system includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it performs the posture control method for the airbag-supported flexible floating raft vibration isolation system described in any of the above claims.

[0012] Overall, compared with the prior art, the pose control method and system of the airbag-supported flexible floating raft vibration isolation system provided by the present invention are as follows:

[0013] 1. Based on the actual observation positions of multiple measuring points, an iterative reweighted least squares method is used to fit and obtain the reference reference plane of the raft. The elastic deformation of the raft is taken into account, and the reference reference plane that is more suitable for the new installation process is obtained. Then, the displacement of the actual observation position relative to the ideal pose plane is divided into rigid displacement and elastic displacement using the reference reference plane. The rigid displacement and elastic deformation displacement of the raft are approximately separated, providing a more comprehensive index for the selection of airbags and improving the accuracy of the selection of airbags to be adjusted.

[0014] 2. The approximate rigid body displacement and elastic deformation displacement of the raft were calculated. Then, the adjustment effect of the raft was predicted. Based on the change in rigid body displacement of all measuring points and the inflation / deflation correction coefficient after adjusting any airbag, the predicted value of the overall change trend of the raft after adjusting any airbag was proposed. Finally, the approximate optimal control pressure ratio parameter of the airbag was calculated, thus obtaining four indicators, making the selection of airbags more comprehensive.

[0015] 3. The airbag selection process has been optimized. By using multiple indicators in the indicator system and adopting a multi-indicator factor comprehensive decision-making method to select airbags, the accuracy of airbag selection has been improved, and the physical meaning of the airbag selection process has become more reasonable and clear.

[0016] 4. The control strategy design of the airbag-supported flexible floating raft was optimized. The selection of airbags was corrected based on the actual adjustment effect, which improved the control effect of the raft frame. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an airbag-supported flexible floating raft vibration isolation system according to the present invention;

[0018] Figure 2 This is a schematic diagram of the raft frame installation process;

[0019] Figure 3 This is a flowchart for the approximate calculation of rigid body displacement and elastic deformation displacement.

[0020] Figure 4 This is a control flowchart for a flexible floating raft. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0022] Please see Figure 1 and Figure 2 This embodiment provides a pose control method for an airbag-supported flexible floating raft vibration isolation system, wherein the flexible floating raft vibration isolation system includes a raft frame, the raft frame being supported on multiple airbags, and the pose control method includes:

[0023] Obtain the actual observation positions of multiple preset measuring points on the raft frame, wherein the multiple measuring points include at least a plurality of points that are set up one-to-one with the airbag;

[0024] Based on the actual observation positions of multiple measuring points, the reference plane of the raft is obtained by fitting using the iterative reweighted least squares method; wherein, in the iterative reweighted least squares method, the error of the measuring point is obtained based on the deviation between the actual observation position of the measuring point and its position on the reference plane, and an error weight is assigned to the error of each measuring point, with the optimization objective being to minimize the weighted sum of the errors of multiple measuring points;

[0025] Based on the positional distance between the measuring points on the reference plane and the ideal pose plane, the rigid body displacement corresponding to the measuring points is obtained, and the elastic deformation displacement corresponding to the measuring points is obtained according to the actual observation position and the rigid body displacement, thereby obtaining the rigid body displacement and elastic deformation displacement corresponding to the airbag; the distance between the actual observation position and the position on the ideal pose plane, i.e., the displacement minus the rigid body displacement, is the elastic deformation displacement.

[0026] An index system is constructed based on the rigid body displacement, elastic deformation displacement, and pressure corresponding to the airbag. Based on the index system, the airbag to be adjusted is determined and its position and posture are controlled.

[0027] In this embodiment, the flexible floating raft vibration isolation system includes a raft frame with related equipment mounted on it. The raft frame is supported by multiple airbags. Multiple measuring points are provided on the raft frame, with at least one measuring point corresponding to each airbag. Measuring points can also be provided at other locations. Optionally, in addition to the measuring points corresponding to each airbag, multiple additional measuring points are provided in the middle section of the raft frame. The actual observation position of each measuring point can be determined by sensors. The actual observation position and displacement of the measuring point corresponding to each airbag represent the actual observation position and displacement of the corresponding airbag.

[0028] like Figure 1 As shown in some specific embodiments, the airbag-supported flexible floating raft vibration isolation system of the present invention comprises six parts: equipment, base, airbags, displacement sensors, pressure sensors, and raft frame. The operating equipment is located on the raft frame, which is connected to the base via eight airbag vibration isolators evenly arranged on both sides. The system has a total of 12 sets of displacement sensors used to detect the height at various measuring points on the raft frame. One measuring point is set next to each airbag, and four measuring points are set in the middle of the raft frame. Each airbag is equipped with a pressure sensor to measure the actual pressure of the airbag. Two high-speed solenoid valves are connected to a high-pressure air source to realize the inflation and deflation of the airbags. The displacement sensors, airbags, and pressure sensors are all marked in the figure.

[0029] The airbag vibration isolation system effectively controls the raft by changing the amount of gas inside each airbag through inflation and deflation, thereby altering the internal pressure and height of the airbag. Specifically, the airbags are made of elastic materials with significant deformation capacity. By adjusting the air pressure inside the airbags, their stiffness and load-bearing capacity can be changed to adapt to different vibration isolation requirements. When airbags are inflated, the increased air pressure causes them to expand, increasing their stiffness and load-bearing capacity. With the force on the airbag remaining constant, the compression decreases, and the airbag height increases, corresponding to the raft's position. Conversely, when airbags are deflated, the decreased air pressure causes them to contract, reducing their stiffness and load-bearing capacity. With the force on the airbag remaining constant, the compression increases, and the airbag height decreases, corresponding to the raft's position.

[0030] Due to factors such as low structural stiffness of the raft, uneven weight distribution of equipment on the raft, equipment start-up and shutdown, slow air leakage of airbags, and external disturbances, the raft will not only deviate from its equilibrium posture, but will also produce large elastic deformation. At this time, the actual displacement at each measuring point on the raft is composed of the rigid body displacement and elastic deformation displacement of the raft, and the two are coupled with each other and difficult to completely separate.

[0031] First, the establishment of the system coordinate system:

[0032] (1) Control target of the raft and zero-point calibration of the displacement sensor:

[0033] Because the raft frame exhibits elastic deformation, its actual plane cannot be an ideal plane. To represent the overall pose of the raft, a reference plane needs to be iteratively and reweightedly fitted from the coordinates of the measuring points. Before adjusting the raft, the control objective needs to be determined: to adjust the raft's reference plane to the ideal pose plane while minimizing the elastic deformation of the raft and ensuring the pressure of each airbag is as uniform as possible. Figure 2 As shown, during the installation of the floating raft vibration isolation system, after various types of equipment are installed on the raft frame, a jack is installed between the base and the raft frame, next to each airbag. All airbags are in a fully deflated state, and the raft frame is supported by the jacks. Third-party tools (such as a spirit level, laser collimator, etc.) are used to check whether the raft frame is in the ideal pose plane. The height of the corresponding position of the raft frame is adjusted by changing the supporting force of each jack, thereby adjusting the raft frame to the ideal pose. At this time, the reference plane of the raft frame coincides with the ideal pose plane, and the height of each measuring point is its reference height. At this time, the output value of all displacement sensors is set to zero.

[0034] (2) Establishment of the system coordinate system and acquisition of the coordinates of the measuring points:

[0035] When a flexible floating raft vibration isolation system exhibits elastic deformation, controlling the raft's attitude requires first establishing a coordinate system. Taking this embodiment as the research object, the raft frame is considered as a plane, with the origin O of the coordinate system located at the center of gravity when the raft frame is in its ideal orientation plane. To accurately describe the positions of each measuring point and airbag in the system using mathematical methods, the direction of the airbag arrangement under the ideal orientation plane of the raft frame is taken as the Y-axis direction, the Z-axis is perpendicular to the ideal orientation plane of the raft frame and points upward, and the X-axis direction is determined by the right-hand screw rule. The final result of establishing the system coordinate system is as follows: Figure 1 As shown, the displacement sensor's detection value at this time is the displacement between the actual observed position and the initial ideal pose position.

[0036] When the raft is in the ideal position, the reference position, i.e., the coordinates, of each measuring point on the raft is (X... j ,Y j ,0), where j=1~12, X j With Y j These represent the distances of each measuring point along the X and Y axes relative to the center of gravity of the raft. When the raft undergoes rigid body displacement and elastic deformation displacement, deviating from its ideal pose, the measuring points will deviate from their reference height, and the sensor reading h will change accordingly. j This is the result of the coupling of the rigid body displacement and elastic deformation displacement of the raft frame. At this time, the coordinates of the j-th measuring point along the Z-axis in the system coordinate system are:

[0037] z j =h j ;

[0038] If we consider the raft as a rigid body and only consider its rigid body displacement, where α is the roll angle of the raft about the X-axis and β is the pitch angle of the raft about the Y-axis, Let be the distance from the j-th measuring point to the X-axis in the ideal pose of the raft. Let be the distance from the j-th measuring point to the Y-axis in the ideal pose of the raft. After the pose of the raft changes:

[0039]

[0040] in, Let be the distance from the j-th measuring point to the X-axis after the pose of the raft changes. Let be the distance from the j-th measuring point to the Y-axis after the raft's pose changes. Due to the adjustable range of the airbag's vertical height, the maximum deviation angle of the raft from its ideal pose is very small, near 0°. Therefore, the cosine values ​​of α and β are both approximately 1. Hence:

[0041]

[0042] Therefore, if only the rigid body displacement of the raft is considered, the change in the coordinates of the measuring point caused by the change in the raft's attitude angle is very small, and the change in the X-axis of the measuring point before and after the change in the raft's attitude is negligible. j Y j The influence of coordinates is small, and due to the vertical elastic deformation displacement of the raft frame, the lateral coordinate X of the measuring point is also small. j Y j The influence is very small and can be ignored. Therefore, if the raft simultaneously generates rigid body displacement and elastic deformation displacement, the two are coupled to form the total displacement of the raft. The coordinates of each measuring point in the system coordinate system can be approximated as (X... j ,Y j ,z j ), where j = 1 to 12.

[0043] Approximate separation of rigid body displacement and elastic deformation displacement of the raft structure:

[0044] The raft's reference plane not only represents the overall pose of the raft but also approximately separates its rigid body displacement and elastic deformation displacement. Displacement sensor readings only characterize the coupling result of these two displacements. To accurately adjust the raft's pose, precise selection of airbags and their inflation / deflation is necessary. Therefore, it is crucial to determine the raft's reference plane, i.e., an approximate rigid body pose plane, to approximately separate the two displacements. The approximate rigid body displacement and elastic deformation displacement at each airbag's corresponding raft position are used as the two criteria for airbag selection.

[0045] If we only consider the rigid body displacement of the raft, the plane in which the raft is located, as a rigid body, is the rigid body pose plane. The displacement of this plane due to its deviation from the plane when it is in the ideal pose is called the rigid body displacement of the raft.

[0046] When obtaining the approximate rigid body pose plane, if the coordinates of the 12 measuring points are directly fitted into a plane using the ordinary least squares method, and the elastic deformation displacement of the raft is small and can be ignored, it can be approximately assumed that the 12 measuring points are located in the same plane, and the fitting result is relatively accurate.

[0047] However, due to various factors, the actual displacement measured by the displacement sensor is also affected by the elastic deformation of the raft. Some measuring points on the raft exhibit significant elastic deformation, and these points deviate considerably from the actual raft rigid body pose plane; these are called outliers. Since the influence of these outliers on the fitting plane is the same as that of ordinary points, they significantly affect the estimation parameters of the fitted raft rigid body pose plane equation when used in ordinary least squares, making the estimated raft rigid body pose plane inaccurate. Therefore, it is necessary to reduce the influence of these outliers by introducing a weight ω to the coordinate data of all measuring points. jWe assign smaller weights to data from measurement points that are far from the target and larger weights to data from measurement points that are close to the target. We use an iterative reweighted least squares method to approximate the optimal estimate based on the weighted least squares method, thereby obtaining an approximate rigid body pose plane of the raft. Finally, we calculate the approximate rigid body displacement and elastic deformation displacement of the raft.

[0048] The following section uses the iterative reweighted least squares method to obtain the approximate rigid body pose plane of the raft, i.e., the reference plane, and calculates the approximate rigid body displacement and elastic deformation displacement of the raft. The flowchart summarizing the solution steps is as follows: Figure 3 As shown. Specifically, based on the actual observed positions of multiple measuring points, the reference plane of the raft is obtained by fitting using an iterative reweighted least squares method, including:

[0049] The initial value of the error weights of the multiple measurement points is set to 1. In each iteration, the residual between the actual observed position of the measurement point and the regression fitted value is obtained. The error weights are updated using the Huber weight function based on the residual of the measurement point.

[0050] The iteration ends when the maximum change in the residuals at multiple measuring points relative to the previous iteration is less than the adjustment accuracy of the raft, or when the maximum number of iterations is reached, and the reference datum plane is obtained. The specific process is as follows:

[0051] (1) Definition of the optimization index function:

[0052] The general form of the plane equation can be written as:

[0053] Z = aX + bY + c;

[0054] Where a, b, and c are unknowns to be determined in the reference plane.

[0055] The plane equation has only three parameters to be estimated. If there are no measurement errors, the displacement values ​​at three different measuring points are sufficient to solve for a, b, and c. However, random errors always exist in each measurement, i.e.:

[0056] z j =Z j +v j ; or z j =aX j +bY j +c+v j ;

[0057] In the formula, z j For measurement data, Z j v is the true value. j For random error, j = 1 to 12.

[0058] Clearly, by adding up the errors of each measurement, we can obtain the total error:

[0059]

[0060] To minimize the total measurement error, the criterion is to minimize the sum of the squares of the errors from each measurement. Therefore, an optimization index function is defined, namely, minimizing the error function:

[0061]

[0062] Where, ω j Let be the error weight for the j-th measurement point.

[0063] This optimization index function represents the effect of plane fitting using the iterative reweighted least squares method. The iterative reweighted least squares method finds the best function match for the data by minimizing the sum of squared errors. The smaller J is, the better the plane fitting effect. Therefore, the plane equation corresponding to the minimum optimization index function J is the desired plane equation.

[0064] (2) Iterative reweighting to obtain approximate rigid body pose plane equations:

[0065] Finding the equation of a plane can be transformed into finding the equation of a plane. To find the three unknowns and minimize J, we can use the method of finding extrema:

[0066]

[0067] Further simplification of the above formula:

[0068]

[0069] Written in matrix form as follows:

[0070]

[0071] Solving the above matrix equation, we obtain the solutions for a, b, and c as follows: The equation of the plane is obtained as follows:

[0072]

[0073] Therefore, the iterative calculation steps of the iterative reweighted least squares method are as follows:

[0074] a. In the first iteration, the standard least squares method is used for fitting, i.e. The plane equations after the first iteration are obtained.

[0075] b. After the first iteration, the X values ​​of each measurement point are... j Y jSubstituting the coordinates into the plane equation obtained after the first iteration, we obtain the regression fit values ​​for each measuring point after the first iteration. The actual observed values ​​z at each measuring point j with regression fit value By subtracting, we can obtain the residual at each measurement point after the first iteration.

[0076]

[0077] c. The residuals at each measuring point Substituting these values ​​into the Huber weight function yields the new weights for each measurement point. Perform the next iteration to obtain the plane equation after the next iteration.

[0078] The Huber weight function is defined as follows:

[0079]

[0080] in, This represents the error weight of the j-th measurement point during the (n+1)-th iteration. γ is the residual at the j-th measurement point after the n-th iteration; γ is the clipping value, which is numerically equal to the adjustment accuracy σ of the raft.

[0081] The adjustment accuracy σ of the raft frame is the minimum height change among all measuring points after a single adjustment of any airbag. It represents the minimum effect that adjusting the airbag can produce on the raft frame. σ is used as a clipping value to determine whether a measuring point is an outlier, thereby reducing the weight of outliers. A single adjustment includes both inflation and deflation adjustments, and the adjustment time is a preset time. Similarly, when determining the airbag to be adjusted and performing pose adjustment, the adjustment time is also a preset time.

[0082] If the residual of the measuring point is less than the clipping value γ, i.e. the adjustment accuracy σ of the raft, it means that the residual of the measuring point is so small that it is meaningless for improving the pose of the raft. Therefore, it is considered that the actual observed value and the regression fitted value of the measuring point are relatively close, and the measuring point is not an outlier. Otherwise, if the residual of the measuring point is greater than the clipping value γ, it is considered that the measuring point is an outlier. It is necessary to determine the weight of the measuring point in the next iteration based on the magnitude of the residual of the measuring point to weaken the influence of the measuring point on the fitting plane.

[0083] d. Repeat steps b and c, using the new weights for each measurement point for iterative fitting, until the maximum value of the change in the residuals of all measurement points relative to the residuals after the (n-1)th iteration is obtained after the nth iteration. Less than the adjustment accuracy σ of the raft frame, that is:

[0084]

[0085] This indicates that the effect of fitting the plane equation in the nth iteration is no longer meaningful compared to improving the raft's pose. Since the iteration process is a convergent process, the plane equation obtained at this point is already quite close to the desired true rigid body pose plane equation, so the iteration stops. The plane equation obtained after the nth iteration is the raft's reference plane equation, which is also the approximate rigid body pose plane equation. The iteration count can also be used as the criterion for ending the iteration; no specific limitation is imposed.

[0086] (3) Calculation of approximate rigid body displacement and elastic deformation displacement of the raft:

[0087] The rigid body displacement and elastic deformation displacement of the raft can be approximately separated by the plane equations approximating the rigid body pose of the raft. The plane equations are obtained after the nth iteration. This is the approximate rigid body pose plane equation for the raft, where the X values ​​at each measuring point are... j Y j Substituting the coordinates into this plane equation yields the regression fit values ​​for each measuring point. This is the approximate rigid body displacement at the measuring point, and the residual corresponding to each measuring point. This is the approximate elastic deformation displacement at that measuring point. The approximate rigid body displacement and elastic deformation displacement at each measuring point together constitute the total displacement at that measuring point, i.e., the actual observed value z. j ,Right now:

[0088]

[0089] Furthermore, constructing the indicator system also includes:

[0090] Obtain the rigid body displacement change at all measuring points after any airbag inflation adjustment, and the inflation correction coefficient at all measuring points after any airbag inflation adjustment. The inflation correction coefficient is the proportionality coefficient between the actual observed position change of the measuring point and the rigid body displacement change after any airbag inflation adjustment. The overall inflation adjustment trend prediction value of any airbag is obtained by multiplying the rigid body displacement change of the measuring point with the inflation correction system and summing the results at all measuring points.

[0091] Accordingly, the rigid body displacement change of all measuring points after any airbag deflation adjustment is obtained, as well as the deflation correction coefficient of all measuring points after any airbag deflation adjustment, where the deflation correction coefficient is the proportionality coefficient between the actual observed position change of the measuring point and the rigid body displacement change after any airbag deflation adjustment; the overall trend prediction value of the deflation adjustment of any airbag is obtained by multiplying the rigid body displacement change of the measuring point with the deflation correction system and summing all measuring points;

[0092] Based on the actual observation locations of the multiple measuring points, the predicted value of the overall change trend of the airbag inflation adjustment or the predicted value of the overall change trend of the airbag deflation adjustment are selected and added to the index system.

[0093] The specific predictions for the adjustment effect of the flexible raft frame are as follows:

[0094] After approximately separating the rigid body displacement and elastic deformation displacement of the raft, two indicators for airbag selection are obtained. However, due to the complex structural deformation of the flexible raft, the trend and magnitude of displacement changes at various measuring points on the raft after the airbags are inflated and deflated are unknown. To further improve the accuracy of airbag selection, it is necessary to predict the adjustment effect of the raft.

[0095] In the initial state of the system, i.e., under the ideal pose plane, the eight airbags are inflated and deflated for the same duration. Before and after each adjustment, the actual observed values ​​of the total displacement of each measuring point are recorded, and the approximate rigid body pose plane of the raft is calculated from these values. This yields the approximate rigid body displacement at each measuring point on the raft, and the change in rigid body displacement at each measuring point before and after the adjustment is calculated. In other words, starting from the ideal pose, all airbags are inflated and deflated once, and the change in rigid body displacement at all measuring points before and after the adjustment is recorded. This represents the rigid body displacement effect brought about by the airbag adjustment.

[0096] After completing the system initialization inflation / deflation process, let the change in rigid body displacement at the j-th measuring point before and after the i-th airbag inflation be denoted as . The change in rigid body displacement at the j-th measuring point before and after the i-th airbag is deflated. The actual observed change in the total displacement of the j-th measuring point before and after the inflation of the i-th airbag is: The actual observed change in the total displacement of the j-th measuring point before and after the i-th airbag deflates is:

[0097] Therefore, the correction coefficients for the predictive model of the flexible raft adjustment effect are obtained:

[0098]

[0099] In the formula, The inflation correction coefficient for the j-th measuring point after the i-th airbag inflation adjustment; Let be the deflation correction coefficient corresponding to the j-th measuring point after the i-th airbag deflation adjustment; write all coefficients in matrix form to obtain the correction coefficient matrix:

[0100]

[0101] In the formula, K c K f These are the correction coefficient matrices for the raft under inflated and deflated conditions, respectively.

[0102] The sign and absolute value of the correction coefficient reflect the change in displacement relative to the rigid body of the raft, the trend of the total displacement change at the j-th measuring point before and after the inflation and deflation of the i-th airbag, and the magnitude of the deformability at the location of the raft corresponding to that measuring point, respectively. Therefore, the correction coefficient is determined by the properties of the raft itself, and the influence of pressure changes on the correction coefficient is negligible; the correction coefficient can be approximated as constant under different pressure changes.

[0103] Therefore, in a more general case:

[0104]

[0105] Right now:

[0106]

[0107] in, This is the predicted value of the total displacement change of the j-th measuring point relative to the ideal pose plane before and after the i-th airbag is inflated / deflated in any pose of the flexible raft. This represents the change in rigid body displacement at the j-th measuring point before and after the i-th airbag is inflated / deflated.

[0108] Define the rigid body displacement response matrix of the raft:

[0109]

[0110] In the formula, ΔG c ΔG f These are the rigid body displacement response matrices of the raft under inflated and deflated conditions, respectively.

[0111] This matrix includes the changes in rigid body displacement under all adjustment conditions of the raft. The i-th row represents the changes in rigid body displacement at all j measuring points on the raft after adjusting the i-th airbag.

[0112] In the initial state, when selecting an airbag for the first time, or After the k-th airbag adjustment, if the airbag number after the k-th adjustment is i k Calculate the i-th k The change in rigid body displacement at the j-th measuring point before and after the inflation / deflation of an airbag is When selecting the airbag for the (k+1)th time, the i-th element of the rigid body displacement response matrix will be... k Line update, i.e. or

[0113] That is, starting from the ideal pose plane, an inflation and deflation adjustment experiment is conducted on all airbags to obtain the inflation correction coefficient and initial rigid body displacement change of all measuring points after the inflation adjustment of any airbag, and the deflation correction coefficient and initial rigid body displacement change of all measuring points after the deflation adjustment of any airbag.

[0114] When the airbag to be adjusted is determined for the first time and the position is adjusted, the predicted value of the overall change trend of the inflation adjustment in the index system of the airbag is determined based on the inflation correction coefficient of all measuring points corresponding to the airbag and the initial rigid body displacement change. The predicted value of the overall change trend of the deflation adjustment is determined based on the deflation correction coefficient of all measuring points corresponding to the airbag and the initial rigid body displacement change.

[0115] After identifying the airbag to be adjusted and performing pose control at any given time, the rigid body displacement change of the adjusted airbag is updated based on the actual rigid body displacement change of all measuring points after adjustment, for use in the next adjustment judgment.

[0116] Define the matrix for predicting the adjustment effect of the flexible raft:

[0117]

[0118] Therefore, the prediction matrix for the adjustment effect of the flexible raft is the dot product of the correction matrix and the rigid body displacement response matrix:

[0119]

[0120] Similarly:

[0121]

[0122] This matrix includes all adjustments to the flexible raft. The i-th row represents the predicted value of the total displacement change of all j measuring points on the raft after adjusting the i-th airbag, thus predicting the adjustment effect of the flexible raft.

[0123] Predicted value of the overall change trend of the raft frame after adjusting the i-th airbag. The sum of the rows in the i-th row of the matrix used to predict the adjustment effect of the flexible raft is:

[0124]

[0125] The airbag and its inflation / deflation selection strategy are as follows:

[0126] (1) The index system constructed based on the pressure corresponding to the airbag specifically includes:

[0127] Static analysis is performed on the flexible floating raft vibration isolation system to obtain the torque force balance equation of the multiple airbags. Under the torque force balance equation, the optimal control pressure of each airbag is obtained with the goal of minimizing the pressure variance of the multiple airbags.

[0128] The pressure ratio parameter of the airbag is obtained based on the ratio of the actual pressure of the airbag to the optimal control pressure, and the index system includes the pressure ratio parameter.

[0129] The approximate optimal control pressure proportional parameters for the airbag are as follows:

[0130] Based on the above analysis, the rigid body displacement of each airbag can be obtained. Elastic deformation displacement δ i Predicted value of the overall change trend of the raft after adjusting any airbag These three indicators only consider the changes in raft displacement. In order to improve the long-term stability and reliability of the system and extend its service life, it is also necessary to solve for the indicator of the near-optimal control pressure ratio parameter of the airbag. On the basis of ensuring the position control of the raft, the balance of airbag pressure should be taken into account to the maximum extent to prevent individual airbag pressure from being too high or too low.

[0131] If the raft is considered a rigid body, then the moment balance equations of the airbag vibration isolator about the X and Y axes and the force balance equations along the Z axis can be derived from statics theory as follows:

[0132]

[0133] Where P i Let X be the pressure of the i-th airbag. i Y i Let S be the coordinates of the i-th airbag. e G represents the effective area of ​​the airbag, and G is the total weight of the raft and the equipment on it.

[0134] At this point, the system is a statically indeterminate system, P i There are countless solutions. To ensure uniform load distribution across all airbags and reduce coupling between them, while increasing the uniformity of airbag pressure, the constraint is that the pressure variance of each airbag must be minimized. That is:

[0135]

[0136] Therefore, the optimal control pressure P for the i-th airbag is obtained. si as follows:

[0137]

[0138] The above formula represents the optimal control pressure for each airbag when the raft is a rigid body, which is also the approximate optimal control pressure when the raft is a flexible raft.

[0139] The ratio of actual pressure to approximate optimal pressure is defined as the airbag pressure proportionality parameter λ. i Choose the airbag that needs the most control:

[0140]

[0141] (2) Comprehensive decision-making based on multiple factors to select airbags:

[0142] The rigid body displacement of each airbag can be obtained from the above analysis. Elastic deformation displacement δ i Approximate optimal control pressure proportional parameter λ i Predicted value of the overall change trend of the raft after adjusting any airbag To achieve control over the raft's position and attitude, it is necessary to select the most suitable airbag inflation / deflation based on the above four indicators. The selection of airbags can be regarded as a comprehensive decision-making problem involving multiple indicators. Therefore, a subjective weighting method is used to assign weights to each indicator.

[0143] That is, based on the aforementioned indicator system, a multi-indicator factor comprehensive decision-making method is used to determine the airbag to be adjusted and to perform pose control, specifically including:

[0144] Each indicator in the indicator system is dimensionless, and then a subjective weighting method is used to assign weights to each indicator. A comprehensive evaluation index is obtained by weighted summation of the dimensionless indicators, and the airbag to be adjusted is determined based on the comprehensive evaluation index.

[0145] Based on the actual observation positions of the multiple measuring points, determine whether to inflate or deflate the airbag to be adjusted in order to control its position and posture.

[0146] Specifically, the dimensionless processing of each indicator in the indicator system includes:

[0147] Based on the actual observation positions of multiple measuring points, determine whether to use inflation or deflation adjustment strategies for pose control. Based on the favorable trends of various indicators under the adjustment strategy, identify indicators whose values ​​are more favorable as positive indicators and those whose values ​​are less favorable as negative indicators. Dimensionless processing is then applied to both positive and negative indicators. Details are as follows:

[0148] Selection of airbag inflation / deflation and dimensionless data processing:

[0149] Positive indicators are those with higher values, indicating better performance, while negative indicators are those with lower values, indicating better performance. When the raft is in different states, there are two options: inflating or deflating the airbags. Under different choices, the positive and negative indicators will also differ. To ensure that the airbag adjustments are directed in a way that benefits the raft's attitude, the data needs to be dimensionless before assigning weights to each indicator.

[0150] If the sum of the total displacements of all measured points relative to the ideal pose plane is less than 0, that is... This indicates that the airbags need to be inflated to increase the overall displacement of the raft. The desired outcome is the predicted trend of the overall raft change after airbag adjustment, i.e., the predicted value of the overall change trend after inflation adjustment. The larger the value, the better. As positive indicators, when selecting airbags, the smaller the values ​​of rigid body displacement, elastic deformation displacement, and airbag pressure, the better. δ i , λ i This is a reverse indicator; if the sum of the total displacements of all measuring points is greater than 0, that is... The airbags need to be deflated to reduce the overall displacement of the raft, therefore the situation is reversed. As a reverse indicator, δ i , λ i It is a positive indicator.

[0151] The dimensionless processing of positive indicators is as follows:

[0152] The dimensionless processing of the contrarian indicator is as follows:

[0153] in:

[0154]

[0155] In the formula, a im The four indicators represent the i-th airbag. δ i , λ i The value of the m-th indicator, s im Let a be the result of dimensionless processing of the m-th index of the i-th airbag. min a represents the minimum value among different samples for the same indicator. max This represents the maximum value among different samples for the same indicator.

[0156] The weights of each indicator are determined as follows:

[0157] The G1 method, also known as the order relation method, is one of the commonly used subjective weighting methods. The specific steps are as follows:

[0158] The first step is to determine the order relation:

[0159] Rank the evaluation indicators by importance: The specific analysis is as follows.

[0160] Overall trend of raft structure changes after adjustments to each airbag This is of utmost importance for the attitude control of the raft. This indicator reflects whether the adjustment is effective. If the overall trend of change of the raft after the adjustment is opposite to the expected trend, the raft will deviate from the ideal attitude. In this case, the adjustment will have a negative effect on the attitude control of the raft.

[0161] Secondly, the rigid body displacement of the airbag This displacement reflects the overall position and orientation of the raft. On the premise of effective adjustment, the first priority should be to ensure that the overall position and orientation of the raft does not deviate too much from the ideal position and orientation.

[0162] Next is the elastic deformation displacement δ of each airbag. i This displacement reflects the degree of elastic deformation of the raft at the location of the airbag. Based on adjusting the overall orientation of the flexible raft towards the ideal orientation, adjustments are made specifically to address the elastic deformation of the raft.

[0163] Finally, the pressure ratio parameter λ for each airbag. i While meeting the requirements for raft frame adjustment, the pressure of each airbag is made as close as possible to the near-optimal control pressure of the airbag, so that the airbag pressure is not too high or too low, protecting the airbag, increasing the service life of the airbag, and making the system more robust.

[0164] The second step is to determine the importance ratio:

[0165] Once the order relationship is determined, the importance of the evaluation indicators is assigned values ​​based on relevant standards and the author's own experience:

[0166]

[0167] In the formula: r m ∈[1.0,2.0] represents the ratio of the importance of the (m-1)th indicator to the mth indicator; w m w m-1 These are the indicator weights for the m-th and m-1-th indicators, respectively.

[0168] The assignment of order relations is shown in the table below.

[0169] Table 1. Reference Table for Assigning Ordinal Relations

[0170]

[0171] In this embodiment, we take:

[0172]

[0173] The third step is to calculate the subjective weights of each indicator:

[0174] Based on the assigned values, calculate the subjective indicator weight w of the m-th indicator. m :

[0175]

[0176] In this embodiment, the above formula is used to calculate:

[0177]

[0178] Airbag selection:

[0179] After the weights are determined, multiple indicators for each airbag are summed using weighted averages, and the most suitable airbag is selected for adjustment. The comprehensive evaluation index value of the i-th airbag when the system selects an airbag for the k-th time is:

[0180]

[0181] If we let:

[0182]

[0183] Among them, Q k W represents the matrix of comprehensive evaluation index values ​​for the airbags when the system selects airbags for the kth time. k S is the subjective indicator weight matrix of the system when selecting an airbag for the kth time; k Let be the dimensionless index matrix of the system when selecting an airbag for the kth time. Then the above equation can be written in matrix form:

[0184] Q k =S k W k ;

[0185] When selecting an airbag for the kth time, the airbag with the highest comprehensive evaluation index value is selected for inflation and deflation adjustment.

[0186] Furthermore, the pose control method for the airbag-supported flexible floating raft vibration isolation system also includes:

[0187] The comprehensive evaluation index of the airbag is corrected by a reward and punishment factor, and the airbag to be adjusted is determined by the comprehensive evaluation index after the reward and punishment factor correction.

[0188] The reward / penalty factor for all airbags is initially 1;

[0189] After identifying an airbag to be adjusted and performing pose control, the adjustment effect index is obtained. Based on the adjustment effect index, the reward / penalty factor corresponding to the adjusted airbag is updated using a predefined reward / penalty function for the next adjustment judgment. In other words, the control strategy is designed as follows:

[0190] After the airbags are adjusted, to ensure system stability, the selection of airbags needs to be corrected based on the actual control effect. Therefore, the comprehensive evaluation index value of the airbags is corrected based on the actual parameter changes of the raft after adjustment. The control strategy is set with a weighted feedback correction mechanism with reward and penalty factors, so that the selection of airbags before the next adjustment is more in line with the actual situation of the raft, improving the adaptability of the control algorithm to complex working conditions and preventing the occurrence of extreme cases of non-convergence of the control system. The control flowchart of the flexible floating raft is summarized as follows: Figure 4 As shown.

[0191] (1) Calculation of the feedback volume after adjusting the airbag, i.e., the adjustment effect index:

[0192] Compared to the (k-1)th adjustment, after the kth adjustment of the airbag, the following two feedback quantities, i.e., two adjustment effect indicators, can be obtained:

[0193] Overall trend of raft structure change ΔZ trend k as follows:

[0194]

[0195] in, This is the sum of the total displacements of all measuring points relative to the ideal pose plane after the (k-1)th adjustment of the airbag; This represents the sum of the total displacements of all measuring points after the k-th adjustment of the airbag; Let be the change in the total displacement of all measuring points after the k-th adjustment of the airbag. The total displacement of the measuring points represents the difference between their actual observed positions and their positions in the ideal pose plane.

[0196] The change in the maximum total displacement Δz at all measuring points max k as follows:

[0197]

[0198] The overall trend of the raft structure reflects whether the adjustment has improved the control effect on the raft's attitude, while the change in the maximum total displacement among all measuring points reflects whether the adjustment has improved the control accuracy of the raft. Both indicators are inverse indicators; the smaller the value, the better the control effect.

[0199] (2) Feedback correction of the comprehensive evaluation index values ​​of each airbag:

[0200] The k-th adjustment of the i-thk After selecting one airbag, the comprehensive evaluation index value for the (k+1)th airbag selection adjustment needs to be determined. To provide feedback and make corrections, the reward and punishment functions are defined as follows:

[0201]

[0202] Among them, a μ and b μ The influence weights of the two indicators are controlled separately. Specifically, when k=0, It is the reward / penalty factor for the i-th airbag before the (k+1)-th adjustment.

[0203] therefore, This represents the comprehensive evaluation index value of the i-th airbag after feedback correction using reward and punishment factors. After the k-th adjustment, during the (k+1)-th airbag selection adjustment, the comprehensive evaluation index values ​​of all airbags are written in matrix form:

[0204] Q' k+1 =Q k+1 ⊙M k+1 =(S k+1 W k+1 )⊙M k+1 ;

[0205] Among them, Q' k+1 M represents the matrix of comprehensive evaluation index values ​​for the airbags after correction by reward and punishment factors at the (k+1)th airbag selection and adjustment; k+1 Let be the reward / penalty factor matrix for airbag adjustment during the (k+1)th airbag selection, and

[0206] (3) The design of the control process also includes:

[0207] After determining the airbag to be adjusted and adjusting its position at any time, determine whether the maximum total displacement of all measuring points relative to the ideal position plane is greater than the preset control accuracy requirement. If not, the adjustment ends.

[0208] If so, obtain the product of all reward and penalty factors corresponding to the airbag, determine whether the minimum value of the product among all airbags is less than a preset threshold, and determine whether the change in the maximum total displacement among all measuring points relative to the displacement before adjustment is less than the adjustment accuracy of the raft. If neither of these conditions is met, continue adjustment. If at least one condition is met, reduce the control accuracy requirement and / or reset the reward and penalty factors corresponding to all airbags and readjust. Details are as follows:

[0209] After the k-th adjustment and before the (k+1)-th airbag selection adjustment, all airbags in the system have k+1 historical values ​​of reward / penalty factors, that is, from the initial reward / penalty factor 1 before the first adjustment to the reward / penalty factor after the k-th adjustment, a total of k+1 values. For the i-th airbag, after the k-th adjustment, its reward / penalty intensity S is defined. i The product of all reward and penalty factors received by the airbag:

[0210]

[0211] In this formula, t represents the number of reward and punishment factors. If, after the k-th adjustment, the airbag is selected for adjustment in the (k+1)-th time:

[0212] a. The maximum total displacement among all measuring points is greater than the preset control accuracy requirement, i.e.: max(|z j |)>ε;

[0213] Where ε is the preset raft control accuracy value.

[0214] b. The reward or penalty applied to all airbags in the system is within the tolerance threshold, i.e.: min(S i )≥χ;

[0215] Where χ∈(0,1) is the tolerance threshold.

[0216] Then, at this point, the comprehensive evaluation index value Q' after adjustment by reward and punishment factors will continue to be used. k+1 Select the airbag for the (k+1)th adjustment until the raft reaches the required control accuracy, then stop adjusting.

[0217] If the raft does not meet the control accuracy requirements and at least one of the following extreme conditions exists in the system, the preset raft control accuracy requirements are considered too high. It is necessary to reduce the preset control accuracy requirements, reset the reward and punishment forces received by all airbags and readjust them to make the raft converge quickly and avoid system oscillation.

[0218] a. If min(S i ) is lower than χ, i.e., min(S) i If χ < χ, it means that the reward or punishment received by all airbags in the system exceeds the tolerance threshold, and adjusting the airbag pressure is no longer sufficient to improve the raft's position.

[0219] b. The largest change in total displacement among all measuring points The adjustment accuracy σ of the raft is less than that of the raft. They believe that the adjustment was ineffective.

[0220] In another embodiment, a posture control system for an airbag-supported flexible raft vibration isolation system is also provided. The system includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it performs the posture control method for the airbag-supported flexible raft vibration isolation system described above.

[0221] Furthermore, the problems to be solved in this embodiment are: the existing strategies for attitude control of airbag-supported flexible rafts are not perfect; the determination of the reference plane is not well-suited to the existing installation process; the indicators for airbag selection are not comprehensive enough; the physical meaning of the selection process is not clear enough and the accuracy is insufficient; and the design of the control strategy has imperfections. To solve the above technical problems, this embodiment provides the following technical solution:

[0222] An approximate method for calculating the rigid body displacement and elastic deformation displacement of a raft structure includes the following steps:

[0223] (1) Establish the system coordinate system O-XYZ and determine the coordinates of each measuring point. (2) Define the optimization index function to describe the effect of plane fitting. (3) Use the iterative reweighted least squares method to fit the reference plane of the raft, that is, the approximate rigid body pose plane of the raft, and approximately separate the rigid body displacement and elastic deformation displacement of the raft.

[0224] A multi-index comprehensive decision-making factor selection method for airbags includes the following steps: (1) When the raft is in different positions, select the inflation and deflation of the airbags. Under different selection conditions, perform dimensionless processing on the positive and negative index data of each airbag. (2) Use the subjective weighting method to determine the weight of each index, perform weighted summation on the multiple indexes of the airbags, and calculate the comprehensive evaluation index value of each airbag to select the airbag.

[0225] A control strategy design for an airbag-supported flexible raft includes the following steps: (1) Calculate the overall trend of change of the raft frame and the change in the maximum total displacement of the measuring points after adjusting the airbags. (2) Calculate the reward and punishment factors of each airbag using feedback quantity and reward and punishment function, and correct the comprehensive evaluation index value of each airbag based on feedback. (3) Calculate the maximum total displacement of all measuring points and the reward and punishment intensity of each airbag after adjusting the airbags. (4) If the maximum total displacement of all measuring points is greater than the preset control accuracy requirement, and the reward and punishment intensity of all airbags in the system is within the tolerance threshold, continue to adjust until the raft frame reaches the control accuracy requirement. (5) If the reward and punishment intensity of the airbags is outside the tolerance threshold after adjustment, or the change in the maximum total displacement of all measuring points is less than the adjustment accuracy of the raft frame, reduce the control accuracy requirement and reset the reward and punishment intensity of all airbags in the next adjustment.

[0226] This embodiment proposes a posture control strategy for an airbag-supported flexible raft. First, an iterative weighted least squares method, better suited to the new raft installation process, is employed to comprehensively consider all displacement sensor readings to obtain the raft's reference plane, i.e., the approximate rigid body posture plane equation. This represents the overall posture of the raft, and the approximate rigid body displacement and elastic deformation displacement are calculated. Next, the adjustment effect of the raft is predicted, obtaining a predicted value for the overall change trend of the raft after adjusting any airbag. Finally, the approximate optimal control pressure ratio parameter of the airbag is calculated, resulting in four indicators, making the airbag selection more comprehensive. Using these indicators, a multi-indicator factor comprehensive decision-making method is employed to obtain the comprehensive evaluation index value of the airbag, making the airbag selection more reasonable. The reward / penalty factor for each airbag is calculated based on the actual adjustment feedback, providing feedback correction for the airbag selection in the next adjustment, thereby improving the raft's control effect.

[0227] It should also be noted that the illustrations provided in the following embodiments are only schematic diagrams to illustrate the basic concept of the present invention. The illustrations only show the components related to the present disclosure and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the shape, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0228] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for position control of an airbag-supported flexible floating raft vibration isolation system, wherein the flexible floating raft vibration isolation system includes a raft frame, the raft frame being supported on multiple airbags, characterized in that, The pose control method includes: Obtain the actual observation positions of multiple preset measuring points on the raft frame, wherein the multiple measuring points include at least a plurality of points that are set up one-to-one with the airbag; Based on the actual observation positions of multiple measuring points, the reference plane of the raft is obtained by fitting using the iterative reweighted least squares method; wherein, in the iterative reweighted least squares method, the error of the measuring point is obtained based on the deviation between the actual observation position of the measuring point and its position on the reference plane, and an error weight is assigned to the error of each measuring point, with the optimization objective being to minimize the weighted sum of the errors of multiple measuring points; Based on the positional distance between the measuring points on the reference plane and the ideal pose plane, the rigid body displacement corresponding to the measuring points is obtained, and the elastic deformation displacement corresponding to the measuring points is obtained according to the actual observation position and the rigid body displacement, thereby obtaining the rigid body displacement and elastic deformation displacement corresponding to the airbag. An index system is constructed based on the rigid body displacement, elastic deformation displacement, and pressure corresponding to the airbag. Based on the index system, the airbag to be adjusted is determined and its position and posture are controlled.

2. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in claim 1, characterized in that, Based on the actual observation positions of multiple measuring points, the reference reference plane of the raft is obtained by fitting using an iterative reweighted least squares method, specifically including: The initial error weights for the multiple measurement points are all set to 1. In each iteration, the residual between the actual observed position of the measurement point and the regression fitted value is obtained. Based on the residual of the measurement point, the error weights are then used... The weighting function updates the error weights; The iteration ends when the maximum value of the change in residuals at multiple measuring points relative to the previous iteration is less than the adjustment accuracy of the raft, or when the number of iterations reaches the maximum number of iterations, and the reference reference plane is obtained.

3. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in claim 2, characterized in that, The The weighting function is defined as: ； in, For the first During the nth iteration Error weights for each measurement point; For the first After the nth iteration The residuals at each measuring point; The clipping value is numerically equal to the adjustment accuracy of the raft. .

4. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in any one of claims 1-3, characterized in that, The index system constructed based on the pressure corresponding to the airbag specifically includes: Static analysis is performed on the flexible floating raft vibration isolation system to obtain the torque force balance equation of the multiple airbags. Under the torque force balance equation, the optimal control pressure of each airbag is obtained with the goal of minimizing the pressure variance of the multiple airbags. The pressure ratio parameter of the airbag is obtained based on the ratio of the actual pressure of the airbag to the optimal control pressure, and the index system includes the pressure ratio parameter.

5. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in any one of claims 1-3, characterized in that, Building an indicator system also includes: The system obtains the rigid body displacement change at all measuring points after any airbag inflation adjustment, as well as the inflation correction coefficient at all measuring points after any airbag inflation adjustment. The inflation correction coefficient is the proportionality coefficient between the actual observed position change of the measuring point and the rigid body displacement change after any airbag inflation adjustment. By multiplying the rigid body displacement change of the measuring point by the inflation correction coefficient and summing all measuring points, the system obtains the overall predicted value of the inflation adjustment trend of any airbag. Accordingly, the changes in rigid body displacement at all measuring points after the deflation adjustment of any airbag are obtained, as well as the deflation correction coefficient at all measuring points after the deflation adjustment of any airbag. The deflation correction coefficient is the proportionality coefficient between the actual observed position change of the measuring point and the change in rigid body displacement after the deflation adjustment of any airbag. By multiplying the change in rigid body displacement of the measuring point by the deflation correction coefficient and summing all measuring points, the overall trend prediction value of the deflation adjustment of any airbag is obtained. Based on the actual observation locations of the multiple measuring points, the predicted value of the overall change trend of the airbag inflation adjustment or the predicted value of the overall change trend of the airbag deflation adjustment are selected and added to the index system.

6. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in claim 5, characterized in that, Initially, starting from the ideal pose plane, inflation and deflation adjustment experiments were conducted on all airbags to obtain the inflation correction coefficient and initial rigid body displacement change of all measuring points after inflation adjustment of any airbag, as well as the deflation correction coefficient and initial rigid body displacement change of all measuring points after deflation adjustment of any airbag. When the airbag to be adjusted is determined for the first time and the position is adjusted, the predicted value of the overall change trend of the inflation adjustment in the index system of the airbag is determined based on the inflation correction coefficient of all measuring points corresponding to the airbag and the initial rigid body displacement change. The predicted value of the overall change trend of the deflation adjustment is determined based on the deflation correction coefficient of all measuring points corresponding to the airbag and the initial rigid body displacement change. After identifying the airbag to be adjusted and performing pose control at any given time, the rigid body displacement change of the adjusted airbag is updated based on the actual rigid body displacement change of all measuring points after adjustment, for use in the next adjustment judgment.

7. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in any one of claims 1-3, characterized in that, Based on the aforementioned indicator system, a multi-indicator factor comprehensive decision-making method is used to determine the airbag to be adjusted and to perform pose control, specifically including: Each indicator in the indicator system is dimensionless, and then a subjective weighting method is used to assign weights to each indicator. A comprehensive evaluation index is obtained by weighted summation of the dimensionless indicators, and the airbag to be adjusted is determined based on the comprehensive evaluation index. Based on the actual observation positions of the multiple measuring points, determine whether to inflate or deflate the airbag to be adjusted for posture control.

8. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in claim 7, characterized in that, Also includes: The comprehensive evaluation index of the airbag is corrected by a reward and punishment factor, and the airbag to be adjusted is determined by the comprehensive evaluation index after the reward and punishment factor correction. The reward / penalty factor for all airbags is initially 1; After identifying the airbag to be adjusted and performing pose control, the adjustment effect index is obtained. Based on the adjustment effect index, the reward and penalty factors corresponding to the adjusted airbag are updated using a predefined reward and penalty function for the next adjustment judgment.

9. The pose control method for the airbag-supported flexible floating raft vibration isolation system as described in claim 8, characterized in that, Also includes: After determining the airbag to be adjusted and adjusting its position at any time, determine whether the maximum total displacement of all measuring points relative to the ideal position plane is greater than the preset control accuracy requirement. If not, the adjustment ends. If so, obtain the product of all reward and punishment factors corresponding to the airbag, determine whether the minimum value of the product among all airbags is less than the preset threshold, and determine whether the change in the maximum total displacement among all measuring points relative to the displacement before adjustment is less than the adjustment accuracy of the raft. If neither of the two situations occurs, continue the adjustment. If at least one situation occurs, reduce the control accuracy requirement and / or reset the reward and punishment factors corresponding to all airbags and readjust.

10. A position and posture control system for an airbag-supported flexible floating raft vibration isolation system, characterized in that, The system includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it performs the posture control method of the airbag-supported flexible floating raft vibration isolation system as described in any one of claims 1-9.

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