Weight load loading distribution strategy and balance full-automatic calibration method

Abstract

The invention discloses a weight load loading distribution strategy and a balance full-automatic calibration method, and relates to the field of wind tunnel balance calibration, aiming at a given loading load schedule, corresponding weights are automatically loaded / unloaded for each row of loads according to loading loads corresponding to weight strings and according to the weight load loading distribution strategy, and the balance full-automatic calibration method is realized. And stepped loading is realized. And after loading of each weight string is completed, balance data are collected. And after data acquisition is finished, loading the load of the next line in the loading plan table until the loads of all lines in the loading load plan table are loaded, and ending the calibration process. According to the invention, a weight load loading distribution strategy is designed, when the load of the weight string is switched, the number state of weight state changes on the weight string can be minimized, so that the impact of weight loading / unloading on the balance is reduced, the balance safety is guaranteed, and the calibration efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of wind tunnel balance calibration, and more particularly to a weight load distribution strategy and a fully automatic balance calibration method. Background Art

[0002] A wind tunnel balance (hereafter referred to as the balance) is a fundamental measurement device used in wind tunnel force testing. It measures the magnitude, direction, and point of application of aerodynamic forces (forces and moments) acting on a test model during wind tunnel testing. A balance calibration device is a measurement device that precisely applies static loads (forces and moments) to the balance along a known coordinate axis to derive the balance equation (the matrix that determines the relationship between the output signal and load) and evaluate balance performance.

[0003] The fully automatic balance calibration device is a fully automatic six-degree-of-freedom body-axis balance calibration system that can realize fully automatic operation of the balance calibration process. Figure 3 Loading structure diagram for the automatic calibration device of balance ( Figure 3 In the figure, 1 is weight string, 2 is balance, and 3 is loading head). The loading head is connected to the balance, and the load of the balance is realized by loading / unloading the weights in the weight string (the weight string structure is shown in FIG. Figure 4 As shown, Figure 4 (In the figure, 4 is the weight, 5 is the tray, and 6 is the cylinder.) The device places 11 weight strings in six directions. The weights in the string are placed on the tray, which is connected to the cylinder. The telescopic cylinder drives the tray up and down, which in turn drives the weights up and down. When the weights move downward, they are suspended on the boom, which is connected to the loading head via a steel strap, thus loading the balance weights. When the weights move upward, they disengage from the boom, unloading the balance weights.

[0004] In the prior art, the automatic calibration process of a balance is as follows: First, for a given loading schedule (the number of rows in the schedule represents the loading steps, and the value in each row represents the load required for each weight string corresponding to the loading step), the load loading in the calibration process starts from the first row. According to the loading load corresponding to each weight string, the corresponding weights are automatically loaded / unloaded to achieve step-by-step load loading. Secondly, after the load of each weight string is completed, the balance data is collected.

[0005] Once again, after data collection is completed, the load of the next row in the loading schedule is loaded until all the loads in the loading schedule are loaded, thus ending the calibration process.

[0006] In the above-mentioned automatic calibration process of the balance, when loading the load of each row, because the weight loading load needs to be switched between the loading steps of the weight string, the conventional method is to unload all the weights and then load the weights according to the load. However, the problem with this method is that the loading load on the balance changes too much. For example, after the current loading load becomes 0, if it is directly changed to the loading load of the next loading step, it will have a greater impact on the balance, which is not conducive to the safe use of the balance and affects the calibration efficiency. Summary of the Invention

[0007] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0008] In order to achieve these objects and other advantages of the present invention, a weight load distribution strategy is provided, comprising: S1. Set the weight loading load of each step as S(k,n), and sort the weights of the weight string from large to small to obtain an array G(n), where G(1) represents the weight of the heaviest weight in the weight string, and G(m) represents the weight of the lightest weight in the weight string; Where h is the total number of rows in the load plan table, k is the row number corresponding to the current load in the load plan table, and k = 1, 2, ... h; m is the number of weights in the weight string, and n = 1, 2, ... m; then S(k, 1) is the load value in the load plan table corresponding to the kth row of the weight string; S2. Set n=1, k=1; S3. Obtain the judgment value Q(k,n) by the following formula: Q(k,n)=S(k,n) / G(n) If Q(k,n)≥1, mark the G(n) weight as loaded and execute S(k,n+1) =S(k,n) -G(n); Otherwise, mark the G(n) weight as unloaded and execute S(k,n+1) = S(k,n); S4. Determine whether S(k,n+1) is equal to 0. If so, mark the remaining weights as unloaded and end the distribution. If not, execute n=n+1 and determine whether n is greater than m. If so, end the allocation; otherwise, return to S3.

[0009] A fully automatic balance calibration method is implemented using a weight load distribution method, comprising: Step 1: Set the number of rows in the load plan table to h; Step 2: Set k=1; Step 3: Read the kth row of loading load in the loading plan table, and use the weight load distribution method to distribute the weight load mode of the kth row; Step 4: Perform corresponding loading or unloading operations on the weights on each weight string according to the allocation method of step 3; Step 5: If the load is loaded, balance data collection is performed; Otherwise, return to step 4; Step 6: After the balance data collection is completed, execute k=k+1; Step 7: Determine whether k is greater than h. If so, the calibration process ends. Otherwise, return to step 3.

[0010] The present invention includes at least the following beneficial effects: the present invention designs a weight load distribution strategy, which can ensure that the number of weight state changes on the weight string is minimized when the load of the weight string is switched, so as to reduce the impact of weight loading / unloading on the balance, which not only ensures the safety of the balance but also improves the calibration efficiency.

[0011] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A flow chart of a weight load distribution strategy according to another embodiment of the present invention; Figure 2 A flow chart of automatic calibration of a balance in one embodiment of the present invention; Figure 3 This is a simplified diagram of the loading structure of a fully automatic calibration device for a balance in the prior art; Figure 4 This is a structural diagram of a weight string in a fully automatic calibration device for a balance in the prior art; Among them, weight string-1, balance-2, loading head-3, weight-4, tray-5, cylinder-6. DETAILED DESCRIPTION

[0013] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0014] In the process of automatic calibration of the balance by the automatic calibration device of the present invention, a weight string weight load distribution strategy is designed, which is used to minimize the load impact of the weight string when the load is switched. It is necessary to maintain the consistency of the load distribution strategy, such as Figure 1 As shown, the policy content it processes is: First, sort the weights in the weight string from largest to smallest, denoted by G(1,2,3,…,m), where m is the number of weights in the weight string, G(n) represents the weight of the nth weight, G(1) represents the weight of the heaviest weight in the weight string, and G(m) represents the weight of the lightest weight in the weight string. The weight loading sequence for each step is denoted by S(k,n), where n=1,2,3,…,m.

[0015] Where, the loading load S(k,1) of the first step is the given load corresponding to the weight string in the k-th row of the loading plan table, is the load value of the weight string in the k-th row of the loading plan table, S(k,n) represents the loading load of the n-th step, k = 1, 2…h, k is the row number corresponding to the current loading load in the loading plan table, and h is the total number of rows in the loading plan table.

[0016] Secondly, the weight load distribution strategy process includes the following steps: S1: Perform the first judgment, divide the load S(k,1) by the weight value G(1) of the first weight in the weight sequence, and record the result as Q(k,1); S2: Judge Q(k,1). If Q(k,1) is greater than or equal to 1, mark the G(1) weight as loaded. If Q(k,1) is less than 1, mark the G(1) weight as unloaded. S3: If the weight G(1) is marked as loaded, then the load S(k,1) of the current step is subtracted from the weight G(1) to obtain the load value S(k,2) of the next step; if the weight G(1) is marked as unloaded, then the load S(k,1) of the current step is used as the load value S(k,2) of the next step; S4, determine whether S(k,2) is 0. If it is 0, mark the remaining weights as unloaded and end the distribution; If S5 is not 0, proceed to the second step of judgment, dividing the load S(k,2) by the weight value G(2) of the second weight in the weight string, and the result is recorded as Q(k,2); S6, judge Q(k,2). If Q(k,2) is greater than or equal to 1, mark the G(2) weight as loaded. If Q(k,2) is less than 1, mark the G(2) weight as unloaded. S7, if the weight G(2) is marked as loaded, then the load S(k,2) of the current step is subtracted from the weight G(2) to obtain the load value S(k,3) of the next step; if the weight G(2) is marked as unloaded, then the load S(k,2) of the current step is used as the load value S(k,3) of the next step; S8, determine whether S(k,3) is 0. If it is 0, mark the remaining weights as unloaded and end the distribution; S9, if it is not 0, proceed to the next step of judgment, repeat S5 to S9 until the number of judgment steps is greater than m, and end the allocation.

[0017] The distribution method of the present invention can realize stepped load loading. When the weight string is switched, the number of weight state changes on the weight string can be minimized to reduce the impact of weight loading / unloading on the balance, which not only ensures the safety of the balance but also improves the calibration efficiency.

[0018] Furthermore, compared with the prior art, the process of automatic calibration of a balance using the weight load distribution strategy of the present invention is mainly based on a given loading load plan table (as shown in Table 1, wherein XL in Table 1 represents the left weight string in the negative X direction, XR represents the right weight string in the negative X direction, X+L represents the left weight string in the positive X direction, X+R represents the right weight string in the positive X direction, Y+L represents the left weight string in the positive Y direction, Y+R represents the right weight string in the positive Y direction, YL represents the left weight string in the negative Y direction, YR represents the right weight string in the negative Y direction, Z+ represents the weight string in the positive Z direction, Z- represents the weight string in the negative Z direction, MY+ represents the weight string in the positive MY direction, MY- represents the weight string in the negative MY direction, MZ+ represents the weight string in the positive MZ direction, and MZ- represents the weight string in the negative MZ direction). For each row of load loading, the corresponding weights are automatically loaded / unloaded according to the weight load distribution strategy according to the loading load corresponding to each weight string, thereby realizing step-by-step load loading. After all weight strings have been loaded, the balance data is collected. After data collection is complete, the next row of the load schedule is loaded, and the calibration process ends when all rows of the load schedule have been loaded.

[0019] Table 1 Loading instance: Perform load distribution on the weight string in row 3, column Y+R in the above loading plan table.

[0020] Assume that the total number of weights in the Y+R weight string is 2.5, 5, 10, 20, 30, 50, 100, 200, 200, 200, then k=3, m=10, S(3,1)=130 (the load in the 3rd row and Y+R column is 130), and the weight order of the weight string is: G(1)=200, G(2)=200, G(3)=200, G(4)=100, G(5)=50, G(6)=30, G(7)=20, G(8)=10, G(9)=5, G(10)=2.5.

[0021] Step 1: Q(3,1)=S(3,1) / G(1)=130 / 200<1, then the weight G(1) is unloaded, S(3,2)= S(3,1)=130, and the next weight is determined; Step 2: Q(3,2)= S(3,2) / G(2) =130 / 200<1, then the G(2) weight is unloaded, S(3,3)= S(3,2)=130, and the next weight is determined; Step 3: Q(3,3) = S(3,3) / G(3) = 130 / 200<1, then the G(3) weight is unloaded, S(3,4) = S(3,3)=130, and the next weight is determined; Step 4: Q(3,4) = S(3,4) / G(4) = 130 / 100>1, then G(4) weight is loaded, S(3,5) = S(3,4)- G(4)=130-100=30, proceed to the next weight judgment; Step 5: Q(3,5) = S(3,5) / G(5) =30 / 50<1, then the G(5) weight is unloaded, S(3,6)= S(3,5)=30, and the next weight is determined; Step 6: Q(3,6) = S(3,6) / G(6) = 30 / 30=1, then the G(6) weight is loaded, S(3,7) = S(3,6)-G(6) = 30-30=0, the remaining weights are marked as unloaded, and the weight distribution is completed; According to the above steps, when the Y+R weight string executes the load in the third row of the loading schedule, the loaded weights are 100 and 30.

[0022] Specifically, the calibration process is as follows Figure 2 As shown, it mainly includes the following steps: Step 1: Read and obtain the total number of rows in the load plan table as h; Step 2: Set k=1; Step 3: Read the kth row of loading load in the loading plan table, and use the weight load distribution method to distribute the weight load mode of the kth row; Step 4: Perform corresponding loading or unloading operations on the weights on each weight string according to the allocation method of step 3; Step 5: If the load is loaded, balance data collection is performed; Otherwise, return to step 4; Step 6: After the balance data collection is completed, execute k=k+1; Step 7: Determine whether k is greater than h. If so, the calibration process ends. Otherwise, return to step 3.

[0023] The above solution is only an illustration of a preferred embodiment, but is not limited thereto. When implementing the present invention, appropriate replacements and / or modifications can be made according to user needs.

[0024] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and exemplary embodiments. They can be applied to a variety of fields suitable for the present invention. Further modifications will be readily apparent to those skilled in the art. Therefore, the present invention is not limited to the specific details and illustrations shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims

1. A weight load distribution strategy, characterized in that: include: S1. Set the weight loading load of each step as S(k,n), and sort the weights of the weight string from large to small to obtain an array G(n), where G(1) represents the weight of the heaviest weight in the weight string, and G(m) represents the weight of the lightest weight in the weight string; Where h is the total number of rows in the load plan table, k is the row number corresponding to the current load in the load plan table, and k = 1, 2, ... h; m is the number of weights in the weight string, and n = 1, 2, ... m; then S(k, 1) is the load value in the load plan table corresponding to the kth row of the weight string; S2. Set n=1, k=1; S3. Obtain the judgment value Q(k,n) by the following formula: Q(k,n)=S(k,n) / G(n) If Q(k,n)≥1, mark the G(n) weight as loaded and execute S(k,n+1) =S(k,n) -G(n); Otherwise, mark the G(n) weight as unloaded and execute S(k,n+1) = S(k,n); S4. Determine whether S(k,n+1) is equal to 0. If so, mark the remaining weights as unloaded and end the distribution. If not, execute n=n+1 and determine whether n is greater than m. If so, end the allocation; otherwise, return to S3.

2. A fully automatic balance calibration method, which uses the weight load distribution method according to claim 1, characterized in that: include: Step 1: Set the number of rows in the load plan table to h; Step 2: Set k=1; Step 3: Read the kth row of loading load in the loading plan table, and use the weight load distribution method to distribute the weight load mode of the kth row; Step 4: Perform corresponding loading or unloading operations on the weights on each weight string according to the allocation method of step 3; Step 5: If the load is loaded, balance data collection is performed; Otherwise, return to step 4; Step 6: After the balance data collection is completed, execute k=k+1; Step 7: Determine whether k is greater than h. If so, the calibration process ends. Otherwise, return to step 3.

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