High-precision calculation method for weighing of livestock farm feed tower under wind load condition

Abstract

The invention provides a high-precision calculation method for weighing a farm feed tower under a wind load condition, and belongs to the technical field of weight calculation methods. The method specifically comprises the following steps that the dead weight of a feed tower, the total weight after feed is added and the static supporting force of each supporting leg are determined; the wind direction is measured, and the supporting legs are divided into a windward group and a leeward group according to the vertical symmetry plane, perpendicular to the wind direction, of the center of the material tower; respectively calculating the vertical distance from each supporting leg of the windward group and the leeward group to the symmetry plane, calculating the wind load force and the upsetting moment by combining the wind speed to establish a supporting leg counter-force mathematical model under the wind load, and obtaining the dynamic supporting force of each supporting leg; superposing the static supporting force and the dynamic supporting force of each supporting leg to obtain an estimated supporting force of each supporting leg; the estimated supporting force of each supporting leg under the wind load and the supporting force, measured in real time, of each supporting leg are used for conducting filtering calculation to obtain accurate dynamic supporting force of the wind load; and deducting the accurate wind load dynamic supporting force and the dead weight of the feed tower to obtain the actual accurate weight of the feed.

Description

Technical Field

[0001] This invention belongs to the technical field of weight calculation methods, specifically relating to a high-precision calculation method for weighing feed towers in livestock farms under wind load conditions. Background Technology

[0002] Feed silos are typically designed as tall structures, bearing the weight of large amounts of material and the influence of the external environment, especially wind. Wind load, as a type of external load, acts on the silo structure over a long period, potentially causing vibration and deformation, thus affecting the accuracy of the silo's weighing system. The silo's weighing system usually relies on the reaction force of the support legs to measure feed weight; deformation of the support legs caused by wind load will alter the distribution of the reaction force. For example, the Chinese patent CN117824809A describes a method for accurately weighing feed in livestock farms: This method achieves high-precision measurement of dynamic and static feed weight through data acquisition and preprocessing, and Kalman filtering optimization. The main technical process is as follows: First, weighing data is collected by sensors, amplified, and summed across multiple channels to convert it into an initial weight value. Then, a moving average filter is used to reduce fluctuations in the original data. Subsequently, Kalman state equations are established for three states: static load, feeding, and unloading. Combined with the observation equation, prior error covariance matrix, and gain coefficient, the weight is dynamically optimized, ultimately outputting an accurate weight and updating the error covariance matrix to support the next cycle calculation. This method overcomes the limitation of traditional methods in measuring dynamic weight by establishing corresponding Kalman state equations for dynamic processes such as feed feeding and unloading, distinguishing between static load, feeding, and unloading states. However, under wind load conditions, it can cause the feed tower to vibrate or sway, resulting in additional vibration noise in the data collected by the sensor. Furthermore, neither the filtering nor the Kalman equation in this method is designed with a correction mechanism for wind load interference, leading to a decrease in measurement accuracy under wind load conditions. Additionally, parameters such as prediction error variance and observation error variance in the Kalman filter need to be calibrated through multiple experiments. If the feed type or environment of the farm changes, the parameters need to be readjusted; otherwise, accuracy fluctuations are likely to occur. Moreover, while the moving average filter reduces noise by averaging data within a window, setting the window size too large can cause a lag in response to sudden changes in feeding and unloading speeds, affecting the timeliness of instantaneous dynamic weight measurement. Therefore, existing technologies can only weigh feed under windless conditions and measure the weight of feed during feeding or unloading. Due to the limitations of the calculation methods for sensor measurement signals, the accuracy of the output data is not high; and there is also the limitation of dynamic monitoring of feed under wind conditions. Summary of the Invention

[0003] This invention addresses the problems of existing technologies by providing a highly accurate method for calculating the weight of feed towers in livestock farms under wind load conditions.

[0004] To achieve the above objectives, the technical solution adopted in this application is as follows: A high-precision calculation method for weighing a feed tower in a livestock farm under wind load conditions, comprising a feed tower, wherein the feed tower adopts a support structure with an even number of legs; the number of legs is n, n>1, and the specific steps are as follows: S1: Determine the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower when there is no wind load; S2: Measure the wind direction and divide the tower legs into windward and leeward groups according to the wind direction; fit all legs into two left-right symmetrical virtual leg structures along the wind direction; and establish a dynamic support force distribution model of the tower virtual legs under wind load conditions to obtain the dynamic support force of each leg. Specifically, a dynamic support force distribution model for the virtual legs of the material tower under wind load conditions was established to obtain the dynamic support force of each leg. This involved: measuring the wind direction and dividing the tower legs into a windward group and a leeward group based on the wind direction; fitting all legs into two virtual leg structures symmetrical about a symmetrical neutral plane based on the symmetry of the tower leg arrangement, including a windward virtual leg group and a leeward virtual leg group; and simplifying the tower legs into a first-order statically indeterminate structure to obtain the dynamic support force of each leg. S3: The static and dynamic support forces of each outrigger are superimposed to obtain the estimated support force of each outrigger; the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger are filtered and calculated to obtain the accurate total dynamic support force under wind load; the accurate total dynamic support force under wind load is obtained by subtracting the static support force of each outrigger from the accurate total dynamic support force under wind load. S4: Subtract the precise wind load dynamic support force and the weight of the feed tower from the total weight of the feed tower and the feed to obtain the actual precise weight of the feed.

[0005] Preferably, in step S1, the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower are determined under no-wind load conditions, specifically as follows: Based on the force sensors installed at the bottom of each support leg of the pylon, ensure that the pylon is placed horizontally in a windless environment, with no looseness or suspension at the bottom of the support legs; if the pylon is empty, record the pylon's self-weight G. 塔体 And measure the diameter of the feed tower. Tower height ; Force sensors installed at the bottom of each support leg of the pylon are used to collect reaction force data of all legs under no wind load. The average value is taken after 10 consecutive samplings to obtain the static support force of each support leg. Calculate the algebraic sum of all outrigger reactions. ; .

[0006] Preferably, in step S2, the wind direction is measured and the tower legs are divided into windward and leeward groups based on the wind direction; all legs are fitted into two left-right symmetrical virtual leg structures along the wind direction, and a dynamic support force distribution model for the virtual legs of the tower under wind load conditions is established, specifically as follows: Wind speed and direction sensors are installed near the material tower to collect wind speed (v) and wind direction in real time; wind load is calculated based on wind speed (v). And the overturning moment M; Based on the structural drawings of the material tower and the wind direction, the legs are divided into the windward group on the windward side and the leeward group on the leeward side according to the vertical symmetry plane passing through the center of the material tower perpendicular to the wind direction; the legs are sequentially recorded as the first to the nth. Measure the vertical distance from each support leg to the vertical symmetrical plane of the tower center, which is perpendicular to the wind direction; ensure that the vertical distances of the windward support legs and the leeward support legs correspond one-to-one.

[0007] As a preferred embodiment, based on the material tower structural drawings and wind direction, the support legs are divided into a windward group on the windward side and a leeward group on the leeward side according to the vertical symmetry plane passing through the center of the material tower perpendicular to the wind direction; the support legs are sequentially denoted as the first to the nth, specifically: Based on the tower structure drawings and wind direction, the initial zero-degree position of the wind direction sensor is set as due north, and the positive Y-axis is set on the horizontal plane. The positive X-axis is set as due east, which is perpendicular to the Y-axis on the horizontal plane. The horizontal plane is further divided into four quadrants as usual. The support legs are numbered as follows: facing due north, they are numbered counterclockwise from number 1 to number n. The initial angle between each support leg and due north is determined according to the installation position. The vertical symmetry plane passing through the center of the tower and perpendicular to the wind direction is determined as the neutral symmetry plane. This neutral symmetry plane divides the support legs into the windward group on the windward side and the leeward group on the leeward side. The support leg numbers that fall into the windward group and the leeward group are further determined.

[0008] Preferably, the vertical distance from each support leg to the vertical symmetry plane of the tower center perpendicular to the wind direction is measured; ensuring that the vertical distances of the windward support legs and the leeward support legs correspond one-to-one, specifically: The vertical distance from each support leg to the vertical plane of symmetry of the tower center, perpendicular to the wind direction, is determined as follows: First, determine the projection of each support leg position onto the horizontal plane. The line connecting this projection point and the projection of the tower center onto the horizontal plane is equal to the angle between the tower radius R and the Y-axis. , The included angle ranges from 0 to 180°. The included angle β between the neutral symmetry plane and the due north direction is further determined, with the included angle β ranging from 0 to 90°. Secondly, when a northeasterly wind acts on the feed tower, and the neutral plane is located in the second or fourth quadrant, the distance between the leeward support legs and the neutral plane is... =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( When the wind is from the southwest, the distance between the outriggers of the windward group and the neutral surface. =Rsin( The distance between the outriggers of the leeward group and the neutral plane. =Rsin( ); When a southeast wind acts on the feed tower, and the neutral plane is located in the first or third quadrant, the distance between the support legs of the windward group and the neutral plane is... =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( When the wind is from the northwest, the distance between the outriggers of the leeward group and the neutral plane. =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( ).

[0009] As a preferred approach, the support legs of the feed tower are simplified into a statically indeterminate structure, and the dynamic support force of each support leg is obtained as follows: After force analysis of a statically indeterminate structure, the support leg of the pylon is simplified into a statically indeterminate structure, using redundant constraint reaction forces. As unknowns, establish the deformation compatibility equations:

[0010] in, For unit redundant unknown constraint reaction force =1 when acting alone on the basic structure, the resulting along The displacement; When wind load acts alone, along Displacement in direction; The deformation compatibility equations are solved to obtain By combining the static equilibrium equation, the dynamic support force of the outriggers of the windward group and the windward group is obtained. .

[0011] Preferably, the deformation compatibility equation is as follows:

[0012] in, The diameter of the feed tower, The height of the material tower, This is the wind load.

[0013] Preferably, the dynamic support force of the outriggers of the windward group is obtained by combining the static equilibrium equation. and Specifically: The support constraint reactions can be solved using the force method canonical equations. According to the principle of static equilibrium, the equation can be obtained as follows: + =0; The leeward outriggers experience wind load along their direction: ; The virtual outriggers of the windward assembly experience forces along the outrigger direction due to wind load: ; Based on the above formula, the constraint reaction force at the support can be calculated. and Subsequently, the vertical symmetry planes from each support leg to the center of the tower, perpendicular to the wind direction, are sequentially set as follows: , , … … Based on the vertical distance from the support legs of the feed tower to the neutral plane of the feed tower. The dynamic support force of the outriggers in the leeward group is allocated to n outriggers. ,in =1~n; then the dynamic supporting force of the outriggers of the leeward group is: The formula is: ; The dynamic support force of the outriggers facing the wind is The formula is: .

[0014] Preferably, in step S3, the estimated support force of each outrigger is obtained by superimposing the static support force and dynamic support force of each outrigger, specifically as follows: Estimated support force of the outriggers .

[0015] Preferably, in step S3, the estimated support force of each outrigger is obtained by superimposing the static support force and dynamic support force of each outrigger, specifically as follows: Estimated support force of the windward outriggers ; Estimated support force of the leeward support legs .

[0016] Preferably, in step S3, the accurate dynamic support force under wind load is obtained by filtering and calculating using the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger. Specifically: The real-time support force of the windward support leg is obtained by pressure sensors installed at the bottom of each support leg of the silo. ; The Kalman filter is used to calculate the accurate dynamic wind load support force. The specific operation is as follows: Construct the prior estimation formula: ; in, for Time's up The state transition matrix at time t; From Time's up Control matrix at time; The Gaussian white measurement noise vector; for The state parameter vector at time: The vector formed; Formula for constructing the prior error covariance matrix : ; in, Q Let be the error covariance matrix of the system process noise; The formula for calculating the Kalman filter gain is as follows: : ; in, The observation matrix of the object, This is the covariance error matrix of the noise in the measurement data; The Kalman gain is constructed using the following formula: ; in, The observation matrix; Specifically, the measured values ​​of each outrigger force sensor Composed of; By combining the Kalman gain, prior covariance, and observation matrix, the posterior covariance matrix required for the next filtering iteration can be calculated according to the following formula: ; The optimal estimate at each iteration of the previous filter is used as a priori estimate to predict the current state. Then, the predicted value is corrected using the real-time measured outrigger support force to obtain the optimal estimate. The iteration finally yields the accurate total support force of each outrigger under wind load conditions. Furthermore, the dynamic support force caused by wind load on each outrigger can be obtained. ; The static support force is applied to each outrigger individually; Calculate the algebraic sum of all outrigger reactions: ; Calculate the dynamic support force caused by all wind loads: ; Calculate the net weight of feed in the feed tower: .

[0017] Compared with the prior art, the advantages and positive effects of the present invention are as follows: This application presents a high-precision calculation method for weighing feed towers in livestock farms under wind load conditions. This method considers the influence of outdoor wind loads and provides a way to accurately weigh feed in livestock farms around the clock. Specifically, it is implemented through the following steps: First, determine the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower when there is no wind load. Then, measure the wind direction and divide the feed tower legs into windward and leeward groups based on the wind direction. Based on symmetry theory, establish a mathematical model of the dynamic support force of the feed tower legs under wind load conditions to obtain the dynamic support force of each leg. Finally, calculate the static and dynamic support forces of each leg. The estimated support force of each outrigger is obtained by superimposing the values. The accurate dynamic support force of the wind load is obtained by filtering the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger. Finally, the accurate dynamic support force of the wind load and the weight of the feed tower are subtracted from the total weight of the feed tower and the feed to obtain the actual accurate weight of the feed. A correlation model between wind load and outrigger reaction force is established by using the statically indeterminate structural force method. Combined with the Kalman filter algorithm to reduce noise in the measurement data, wind load interference is effectively eliminated. The weighing error can be reduced from 0.112% to 0.342% to 0.0076% to 0.0128%, which significantly improves the accuracy. Furthermore, by utilizing the principle of symmetry to group the outriggers, only data collection and noise reduction are required for n windward outriggers, while the results can be directly reused for leeward outriggers, reducing the number of sensors and computational load by 50%, thereby reducing hardware costs and computational load. Furthermore, the high-precision calculation method for weighing farm feed towers under wind load conditions proposed in this application is applicable to all farm feed towers with even-numbered leg structures. It can achieve accurate weighing for various wind load conditions such as gradual wind, random wind, and gusts, without requiring additional modifications to the feed tower structure and is easily integrated into existing weighing systems. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a simplified diagram of the 6-leg feed tower of the present invention; Figure 2This is a diagram showing the lateral forces acting on the two legs of the present invention. Figure 3 This is a diagram showing the state of the two legs of the present invention under lateral force; Figure 4 This is a symmetrical load force diagram of the present invention; Figure 5 This is a force diagram of the antisymmetric load of the present invention; Figure 6 This is a stress diagram of the overall structure of the feed tower of the present invention; Figure 7 This is a stress diagram of the left half of the material tower structure of the present invention. Detailed Implementation

[0020] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0021] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0022] Example 1, as Figures 1 to 3 As shown in the present application, a high-precision calculation method for weighing a feed tower in a farm under wind load conditions includes a feed tower, wherein the feed tower adopts a support structure with an even number of legs; the number of legs is n, n>1, and in this embodiment, n=8, that is, the feed tower has a total of eight legs; The specific steps are as follows: S1: Determine the weight of the tower itself, the total weight of the tower and feed, and the static support force of each leg of the tower when there is no wind load, based on the force sensor installed at the bottom of each support leg. S2: Measure the wind direction and divide the tower legs into windward and leeward groups according to the wind direction; fit all legs into two left-right symmetrical virtual leg structures along the wind direction, and establish a dynamic support force distribution model of the tower virtual legs under wind load conditions to obtain the dynamic support force of each leg. Specifically, a dynamic support force distribution model for the virtual legs of the material tower under wind load conditions was established to obtain the dynamic support force of each leg. This involved: measuring the wind direction and dividing the tower legs into a windward group and a leeward group based on the wind direction; fitting all legs into two virtual leg structures symmetrical about a symmetrical neutral plane based on the symmetry of the tower leg arrangement, including a windward virtual leg group and a leeward virtual leg group; and simplifying the tower legs into a first-order statically indeterminate structure to obtain the dynamic support force of each leg. The method of "fitting all legs into two approximately symmetrical virtual leg structures along the wind direction" utilizes symmetry theory, which effectively simplifies the analysis process. This is especially important when dealing with structures exhibiting geometric or load symmetry, where the design of tower legs often employs a symmetrical layout. This results in a certain degree of symmetry in the entire tower under static loads. Any load acting on a symmetrical structure can always be divided into symmetrical and anti-symmetrical loads, calculated separately. The superposition principle is then used to superimpose the results of the symmetrical and anti-symmetrical structures under arbitrary loads to obtain the result of the original symmetrical structure under arbitrary loads. Under symmetrical loads, the deformation is symmetrical, the bending moment diagram and axial force diagram are symmetrical, and the anti-symmetrical internal forces on the symmetrical plane are zero. Under anti-symmetrical loads, the deformation is anti-symmetrical, the bending moment diagram and axial force diagram are anti-symmetrical, while the shear force diagram is symmetrical. Towers typically have symmetrical support with 6 or 8 legs, such as... Figure 1 As shown, under the action of eccentric load, wind load, etc., one side is under tension and the other side is under compression, similar to the state of two legs under lateral force. The eight-leg material tower affected by eccentric load, wind load, etc. can be simplified into a structure with two legs under lateral force as follows. Figure 2 As shown; where Figure 1 The symmetrical structure of the six-legged material tower has three redundant constraint forces under wind load, making it a cubically statically indeterminate structure. This means the number of unknown reactions is three more than the static equilibrium equations, making direct solution difficult. Since the wind load lacks symmetry, it is decomposed into symmetrical and anti-symmetrical loads, such as... Figure 3 As shown; Figure 4 To simplify the stress condition of the symmetrical structure of the 8-legged material tower under symmetrical wind load, the symmetrical structure has two redundant unknown forces, and the anti-symmetrical internal forces on the symmetry plane are zero. Figure 5 To simplify the stress condition of an 8-legged symmetrical tower structure under anti-symmetrical wind load, where the symmetrical structure has one redundant unknown force and the symmetrical internal forces on the symmetry plane are zero, and to calculate the leg reactions of the 8-legged tower, only the case of the tower under anti-symmetrical wind load is considered; to simplify the calculation, the left half of the original structure can be taken for study, such as... Figure 6 and Figure 7 As shown, according to the symmetry theory, the shear force and bending moment on the cross section of the axis of symmetry are both zero. The simplified structure is a first-order statically indeterminate structure. The original third-order statically indeterminate structure is simplified to a first-order statically indeterminate structure, containing only one redundant unknown force, which greatly reduces the solution complexity. Under antisymmetric wind load, the reaction forces of the outriggers at symmetrical positions exhibit a strictly antisymmetric relationship; As in this application, the windward outriggers include outriggers 1 to 4; the leeward outriggers include outriggers 5 to 8. According to the wind direction, the reaction forces of the supporting legs symmetrically positioned on the vertical plane of the tower's center are equal in magnitude, i.e. = , = , = , = The absolute values ​​of the reaction forces of the four symmetrical outriggers are equal, but their signs are opposite. The magnitude of the reaction force is proportional to the distance from the outrigger to the vertical plane of symmetry of the tower center in the wind direction. That is, the greater the distance, the greater the absolute value of the reaction force. This rule reduces the amount of calculation by half. Only the reaction force of one outrigger needs to be solved, and the reaction force of the other side can be derived through symmetry.

[0023] S3: The static and dynamic support forces of each outrigger are superimposed to obtain the estimated support force of each outrigger; the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger are filtered and calculated to obtain the accurate total dynamic support force under wind load; the accurate total dynamic support force under wind load is obtained by subtracting the static support force of each outrigger from the accurate total dynamic support force under wind load. S4: Subtract the precise wind load dynamic support force and the weight of the feed tower from the total weight of the feed tower and the feed to obtain the actual precise weight of the feed.

[0024] In step S1, the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower are determined under no-wind load conditions. Specifically: Based on the force sensors installed at the bottom of each support leg of the pylon, ensure that the pylon is placed horizontally in a windless environment, with no looseness or suspension at the bottom of the support legs; if the pylon is empty, record the pylon's self-weight G. 塔体 And measure the diameter of the feed tower. Tower height ; Add a known weight of feed G into the feed tower. 饲料总重 Record the total weight G of the feed tower and feed. 总 ; Force sensors installed at the bottom of each support leg of the pylon are used to collect reaction force data of all legs under no wind load. The average value is taken after 10 consecutive samplings to obtain the static support force of each support leg. Calculate the algebraic sum of all outrigger reactions. ; ;Calculation obtained Subsequent verification showed its similarity to G. 总 ×g (g is the acceleration due to gravity, taken as 9.8 m / s²) 2 The deviation is ≤0.1% to ensure accurate reaction force measurement under no-wind load conditions; In step S2, the wind direction is measured and the tower legs are divided into windward and leeward groups based on the wind direction; all legs are fitted into two left-right symmetrical virtual leg structures along the wind direction, and a dynamic support force distribution model for the virtual legs of the tower under wind load conditions is established, specifically as follows: Wind speed and direction sensors are installed near the material tower to collect wind speed (v) and wind direction in real time; the wind load F is calculated based on the wind speed (v). W And the overturning moment M; Based on the structural drawings of the material tower and the wind direction, the legs are divided into the windward group on the windward side and the leeward group on the leeward side according to the vertical symmetry plane passing through the center of the material tower perpendicular to the wind direction; the legs are sequentially recorded as the first to the nth. Measure the vertical distance from each outrigger to the vertical symmetrical plane of the tower center, which is perpendicular to the wind direction; ensure that the vertical distances of the windward outriggers and the leeward outriggers correspond one-to-one. For example, the distance from the first outrigger 1 of the first group to the centerline is... Then the distance from the first leeward outrigger n+1 of the first group to the central axis is also... In this application, the eight outriggers are divided into four groups, and the vertical distances of the four groups of outriggers to the central axis are respectively... =1.024m =0.8m =0.6m =0.5m; Wind speed and direction sensors are installed near the material tower to collect wind speed (v) and wind direction in real time. The wind speed sensor has a measurement range of 0-30 m / s and an accuracy of ±0.1 m / s. Wind direction data is collected to ensure that the wind direction is perpendicular to the symmetry plane of the material tower; if the wind direction deviates, the wind load coefficient needs to be corrected. The wind load is calculated based on the wind speed (v). And the overturning moment M; =0.5×O×C×S; where O is the air density, which is taken as 1.225 kg / m³ in this application. 3 The drag coefficient is taken as 1.3 assuming the material tower is a steel structure; S is the windward area of ​​the material tower, taken as 8.5m². 2 M= × ; A mathematical model of the additional dynamic support force of the tower under wind load conditions was established based on the symmetry theory, and the dynamic support force of each leg caused by wind load was calculated. Specifically, wind speed and wind direction sensors are installed near the material tower to collect wind speed (v) and wind direction in real time; the wind load is calculated based on the wind speed (v). ; Based on the tower structure drawings and wind direction, the initial zero-degree position of the wind direction sensor is set as due north, and the positive Y-axis is set on the horizontal plane. The positive X-axis is set as due east, perpendicular to the Y-axis on the horizontal plane. The horizontal plane is further divided into four quadrants as usual. The outriggers are numbered as follows: facing due north, they are numbered counter-clockwise from 1 to n, with the initial angle between each outrigger and due north determined based on its installation position. Furthermore, a neutral symmetry plane is determined based on the vertical symmetry plane passing through the center of the tower, perpendicular to the wind direction. This neutral symmetry plane divides the outriggers into a windward group on the windward side and a leeward group on the leeward side. The outrigger numbers that fall into the windward and leeward groups are further determined. The vertical distance from each support leg to the vertical plane of symmetry of the tower center, perpendicular to the wind direction, is determined as follows: First, determine the projection of each support leg position onto the horizontal plane. The line connecting this projection point and the projection of the tower center onto the horizontal plane is equal to the angle between the tower radius R and the Y-axis. (The included angle ranges from 0 to 180°), and further determine the included angle β between the neutral symmetry plane and the due north direction (the included angle ranges from 0 to 90°).

[0025] Secondly, when a northeasterly wind acts on the feed tower, and the neutral plane is located in the second or fourth quadrant, the distance between the leeward support legs and the neutral plane is... =Rsin( ), the distance between the outriggers of the windward group and the neutral plane =Rsin( When the wind is from the southwest, the distance between the outriggers of the windward group and the neutral surface. =Rsin( ), the distance between the outriggers of the leeward group and the neutral plane =Rsin( ).

[0026] When a southeast wind acts on the feed tower, and the neutral plane is located in the first or third quadrant, the distance between the support legs of the windward group and the neutral plane is... =Rsin( ), the distance between the outriggers of the windward group and the neutral plane =Rsin( When the wind is from the northwest, the distance between the outriggers of the leeward group and the neutral plane. =Rsin( ), the distance between the outriggers of the windward group and the neutral plane =Rsin( ); The calculation method for the dynamic support force of the virtual outriggers of the material tower under wind load conditions is as follows: Measure the wind direction and divide the tower legs into windward and leeward groups accordingly. Based on the symmetry of the tower leg arrangement, fit all legs into two virtual leg structures symmetrical about the symmetry neutral plane, including the windward virtual leg group and the leeward virtual leg group. Simplify the tower legs into a first-order statically indeterminate structure, using redundant constraint reaction forces. As unknowns, establish the deformation compatibility equations:

[0027] in, For unit redundant unknown constraint reaction force =1 when acting alone on the basic structure, the resulting along The displacement; When wind load acts alone, along Displacement in direction; The deformation compatibility equations are solved to obtain By combining the static equilibrium equation, the dynamic support force of the outriggers of the windward group and the windward group is obtained. Among them, based on the theory of symmetry: = In this application, =2.047m; The deformation compatibility equation is specifically as follows:

[0028] in, The diameter of the feed tower, The height of the material tower, For wind load; The dynamic support force of the outriggers of the windward group and the windward group is obtained by combining the static equilibrium equation. and Specifically: The support constraint reactions can be solved using the force method canonical equations. According to the principle of static equilibrium, the equation can be obtained as follows: + =0; The leeward outriggers experience wind load along their direction: ; The virtual outriggers of the windward assembly experience forces along the outrigger direction due to wind load: ; Based on the above formula, the constraint reaction force at the support can be calculated. and Subsequently, the vertical symmetry planes from each support leg to the center of the tower, perpendicular to the wind direction, are sequentially set as follows: , , … … Based on the vertical distance from the support legs of the feed tower to the neutral plane of the feed tower. The dynamic support force of the outriggers in the leeward group is allocated to n outriggers. ,in =1~n; then the dynamic supporting force of the outriggers of the leeward group is: The formula is: ; The dynamic support force of the outriggers facing the wind is The formula is: ; In step S3, the estimated support force of each outrigger is obtained by superimposing the static support force and dynamic support force of each outrigger, specifically as follows: Estimated support force of the outriggers .

[0029] In step S3, the accurate dynamic support force under wind load is obtained by filtering and calculating using the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger. Specifically: The real-time support force of the windward support leg is obtained by pressure sensors installed at the bottom of each support leg of the silo. ; The Kalman filter is used to calculate the accurate dynamic wind load support force. The specific operation is as follows: Construct the prior estimation formula: ; in, for Time's up The state transition matrix at time t; From Time's up Control matrix at time; The Gaussian white measurement noise vector; for The state parameter vector at time: The vector formed; Formula for constructing the prior error covariance matrix : ; in, Q Let be the error covariance matrix of the system process noise; The formula for calculating the Kalman filter gain is as follows: : ; in, The observation matrix of the object, This is the covariance error matrix of the noise in the measurement data; The Kalman gain is constructed using the following formula: ; in, The observation matrix; Specifically, the measured values ​​of each outrigger force sensor Composed of; By combining the Kalman gain, prior covariance, and observation matrix, the posterior covariance matrix required for the next filtering iteration can be calculated according to the following formula: ; This matrix will serve as the initial value of the prior covariance for the next filtering iteration, ensuring the recursiveness and continuity of the filtering process. The iteration time of the above filter (i.e. The optimal estimate at time (i.e., time) is used as a priori estimate to predict the current (i.e., time) time. The system first determines the state at a given moment, then uses real-time measured outrigger support forces to correct the predicted values, obtaining the optimal estimate; the iteration ultimately yields the accurate total support force of each outrigger under wind load conditions. Furthermore, the dynamic support force caused by wind load on each outrigger can be obtained. ; The static support force is applied to each outrigger individually; Calculate the algebraic sum of all outrigger reactions: ; Calculate the dynamic support force caused by all wind loads: ; Calculate the net weight of feed in the feed tower: .

[0030] Finally, the precise weight of the feed is obtained by subtracting the accurate wind load dynamic support force and the weight of the feed tower itself from the total weight of the feed tower and the feed.

[0031] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A high-precision calculation method for weighing a feed tower in a livestock farm under wind load conditions, comprising a feed tower, wherein the feed tower adopts a support structure with an even number of legs; the number of legs is n, n>1, characterized in that, The specific steps are as follows: S1: Determine the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower when there is no wind load; S2: Measure the wind direction and divide the tower legs into windward and leeward groups according to the wind direction; fit all legs into two left-right symmetrical virtual leg structures along the wind direction; and establish a dynamic support force distribution model of the tower virtual legs under wind load conditions to obtain the dynamic support force of each leg. Specifically, a dynamic support force distribution model for the virtual legs of the material tower under wind load conditions was established to obtain the dynamic support force of each leg. This involved: measuring the wind direction and dividing the tower legs into a windward group and a leeward group based on the wind direction; fitting all legs into two virtual leg structures symmetrical about a symmetrical neutral plane based on the symmetry of the tower leg arrangement, including a windward virtual leg group and a leeward virtual leg group; and simplifying the tower legs into a first-order statically indeterminate structure to obtain the dynamic support force of each leg. S3: The static and dynamic support forces of each outrigger are superimposed to obtain the estimated support force of each outrigger; the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger are filtered and calculated to obtain the accurate total dynamic support force under wind load; the accurate total dynamic support force under wind load is obtained by subtracting the static support force of each outrigger from the accurate total dynamic support force under wind load. S4: Subtract the precise wind load dynamic support force and the weight of the feed tower from the total weight of the feed tower and the feed to obtain the actual precise weight of the feed.

2. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 1, characterized in that, In step S1, the self-weight of the feed tower, the total weight of the feed tower and feed, and the static support force of each leg of the feed tower are determined under no-wind load conditions. Specifically: Based on the force sensors installed at the bottom of each support leg of the pylon, ensure that the pylon is placed horizontally in a windless environment, with no looseness or suspension at the bottom of the support legs; if the pylon is empty, record the pylon's self-weight G. 塔体 And measure the diameter of the feed tower. Tower height ; Force sensors installed at the bottom of each support leg of the pylon are used to collect reaction force data of all legs under no wind load. The average value is taken after 10 consecutive samplings to obtain the static support force of each support leg. ; Calculate the algebraic sum of all outrigger reactions. ; .

3. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 2, characterized in that, In step S2, the wind direction is measured and the tower legs are divided into windward and leeward groups based on the wind direction; all legs are fitted into two left-right symmetrical virtual leg structures along the wind direction, and a dynamic support force distribution model for the virtual legs of the tower under wind load conditions is established, specifically as follows: Wind speed and direction sensors are installed near the material tower to collect wind speed (v) and wind direction in real time; wind load is calculated based on wind speed (v). And the overturning moment M; Based on the structural drawings of the material tower and the wind direction, the legs are divided into the windward group on the windward side and the leeward group on the leeward side according to the vertical symmetry plane passing through the center of the material tower perpendicular to the wind direction; the legs are sequentially recorded as the first to the nth. Measure the vertical distance from each support leg to the vertical symmetrical plane of the tower center, which is perpendicular to the wind direction; ensure that the vertical distances of the windward support legs and the leeward support legs correspond one-to-one.

4. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 3, characterized in that, Based on the material tower structural drawings and wind direction, the support legs are divided into a windward group on the windward side and a leeward group on the leeward side, according to the vertical symmetry plane passing through the center of the material tower perpendicular to the wind direction; the support legs are sequentially labeled from the first to the nth, specifically: Based on the tower structure drawings and wind direction, the initial zero-degree position of the wind direction sensor is set as due north, and the positive Y-axis is set on the horizontal plane. The positive X-axis is set as due east, which is perpendicular to the Y-axis on the horizontal plane. The horizontal plane is further divided into four quadrants as usual. The support legs are numbered as follows: facing due north, they are numbered counterclockwise from number 1 to number n. The initial angle between each support leg and due north is determined according to the installation position. The vertical symmetry plane passing through the center of the tower and perpendicular to the wind direction is determined as the neutral symmetry plane. This neutral symmetry plane divides the support legs into the windward group on the windward side and the leeward group on the leeward side. The support leg numbers that fall into the windward group and the leeward group are further determined.

5. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 3, characterized in that, Measure the vertical distance from each outrigger to the vertically symmetrical plane of the tower's center, perpendicular to the wind direction; ensure that the vertical distances of the windward outriggers and the leeward outriggers correspond one-to-one, specifically: The vertical distance from each support leg to the vertical plane of symmetry of the tower center, perpendicular to the wind direction, is determined as follows: First, determine the projection of each support leg position onto the horizontal plane. The line connecting this projection point and the projection of the tower center onto the horizontal plane is equal to the angle between the tower radius R and the Y-axis. , The included angle ranges from 0 to 180°. The included angle β between the neutral symmetry plane and the due north direction is further determined, with the included angle β ranging from 0 to 90°. Secondly, when a northeasterly wind acts on the feed tower, and the neutral plane is located in the second or fourth quadrant, the distance between the leeward support legs and the neutral plane is... =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( When the wind is from the southwest, the distance between the outriggers of the windward group and the neutral surface. =Rsin( The distance between the outriggers of the leeward group and the neutral plane. =Rsin( ); When a southeast wind acts on the feed tower, and the neutral plane is located in the first or third quadrant, the distance between the support legs of the windward group and the neutral plane is... =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( When the wind is from the northwest, the distance between the outriggers of the leeward group and the neutral plane. =Rsin( The distance between the outriggers of the windward group and the neutral plane. =Rsin( ).

6. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 3, characterized in that, The support legs of the feed tower are simplified into a statically indeterminate structure, and the dynamic support force of each support leg is obtained as follows: After force analysis of a statically indeterminate structure, the redundant constraint reactions are transformed into support reactions. As unknowns, establish the deformation compatibility equations: in, For unit redundant unknown constraint reaction force =1 when acting alone on the basic structure, the resulting along The displacement; When wind load acts alone, along Displacement in direction; The deformation compatibility equations are solved to obtain By combining the static equilibrium equation, the dynamic support force of the outriggers of the windward group and the windward group is obtained. .

7. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 6, characterized in that, The deformation compatibility equation is specifically as follows: in, The diameter of the feed tower, The height of the material tower, This is the wind load.

8. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 7, characterized in that, The dynamic support force of the outriggers of the windward group and the windward group is obtained by combining the static equilibrium equation. and Specifically: The support constraint reactions can be solved using the force method canonical equations. According to the principle of static equilibrium, the equation can be obtained as follows: + =0； The leeward outriggers experience wind load along their direction: ； The virtual outriggers of the windward assembly experience forces along the outrigger direction due to wind load: ； Based on the above formula, the constraint reaction force at the support can be calculated. and Subsequently, the vertical symmetry planes from each support leg to the center of the tower, perpendicular to the wind direction, are sequentially set as follows: , , … … Based on the vertical distance from the support legs of the feed tower to the neutral plane of the feed tower. The dynamic support force of the outriggers in the leeward group is allocated to n outriggers. ,in =1~n; then the dynamic supporting force of the outriggers of the leeward group is: The formula is: ； The dynamic support force of the outriggers facing the wind is The formula is: 。 9. A high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions, as described in claim 8, is characterized in that... In step S3, the estimated support force of each outrigger is obtained by superimposing the static support force and dynamic support force of each outrigger, specifically as follows: Estimated support force of the outriggers .

10. The high-precision calculation method for weighing feed towers in a livestock farm under wind load conditions according to claim 1, characterized in that, In step S3, the accurate dynamic support force under wind load is obtained by filtering and calculating using the estimated support force of each outrigger under wind load and the real-time measured support force of each outrigger. Specifically: The real-time support force of the windward support leg is obtained by pressure sensors installed at the bottom of each support leg of the silo. ; The Kalman filter is used to calculate the accurate dynamic wind load support force. The specific operation is as follows: Construct the prior estimation formula: ； in, for Time's up The state transition matrix at time t; From Time's up Control matrix at time; The Gaussian white measurement noise vector; for The state parameter vector at time: The vector formed; Formula for constructing the prior error covariance matrix : ； in, Q Let be the error covariance matrix of the system process noise; The formula for calculating the Kalman filter gain is as follows: : ； in, The observation matrix of the object, This is the covariance error matrix of the noise in the measurement data; Construct the Kalman gain calculation formula: ； in, The observation matrix; Specifically, the measured values ​​of each outrigger force sensor Composed of; By combining the Kalman gain, prior covariance, and observation matrix, the posterior covariance matrix required for the next filtering iteration can be calculated according to the following formula: ； The optimal estimate at each iteration of the previous filter is used as a priori estimate to predict the current state. Then, the predicted value is corrected using the real-time measured outrigger support force to obtain the optimal estimate. The iteration finally yields the accurate total support force of each outrigger under wind load conditions. Furthermore, the dynamic support force caused by wind load on each outrigger can be obtained. ; The static support force is applied to each outrigger individually; Calculate the algebraic sum of all outrigger reactions: ; Calculate the dynamic support force caused by all wind loads: ; Calculate the net weight of feed in the feed tower: .

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