Test Method for Load Moment of Gas Rudder and Strain Calibration System

Abstract

The present application provides a strain calibration system for a gas rudder, including: a gas rudder system simulation device, a strain gauge, a strain acquisition device, and a load simulation device. Through the strain calibration system, a strain gauge calibration test is carried out. When the load simulation device provides torque to the gas rudder system simulation device, the change of the first strain value of the strain gauge pasted on the gas rudder simulation device with the change of torque is detected, and the functional relationship between the first strain value and the torque is calculated. A method for testing the load torque of a gas rudder is provided. The gas rudder surface is used to replace the torque loading rod in the gas rudder system simulation device to conduct an engine hot test run, and the change of the second strain value of the strain gauge with time is collected. Using the functional relationship between the first strain value and the torque, the load torque of the gas rudder is calculated.

Description

Technical Field

[0001] The present application relates to the field of measurement technologies, and particularly to a method for testing the load torque of a gas rudder and a gas rudder strain calibration system. Background Art

[0002] Under the action of the engine jet flow, while the gas rudder generates a large hinge torque, its operating mechanism will inevitably generate a certain frictional torque during the movement process. Therefore, the gas rudder servo mechanism needs to drive the gas rudder to move according to the command while overcoming the load torque (including the hinge torque and the frictional torque). However, currently, the load torque requirement of the servo mechanism is usually determined according to the maximum hinge torque value of the gas rudder, without considering the frictional torque generated by the operating mechanism, which results in a conservative load torque value and may cause the designed servo mechanism to be unable to generate sufficient driving force to drive the gas rudder to move, thereby leading to a launch failure.

[0003] Currently, under laboratory conditions, the load torque of the gas rudder system under force / thermal loads can be obtained through static / thermal tests. However, compared with the actual working conditions of the gas rudder, the engine jet flow conditions cannot be simulated in the laboratory, so an engine hot-fire test needs to be carried out to obtain the accurate load torque of the gas rudder. When testing the load torque in the engine hot-fire test, a mechanical sensor can be arranged at the operating mechanism of the gas rudder to directly obtain the output force of the servo mechanism. However, this method requires changing the original size of the system to provide space for installing the sensor. At the same time, the cost of the engine test is high and the test preparation time is long. Therefore, if the load torque test method is not fully demonstrated, it will not only affect the test cycle but also the test results. Summary of the Invention

[0004] In view of this, the purpose of the present application is to propose a method for testing the load torque of a gas rudder and a gas rudder strain calibration system, which ensures the authenticity and reliability of the measured experimental data through the standardization of experimental steps, experimental processes, experimental techniques, data processing, etc., and provides a basis for the design of the gas rudder servo mechanism.

[0005] Based on the above purpose, the present application provides a method for testing the load torque of a gas rudder and a gas rudder strain calibration system.

[0006] In a first aspect, the present application provides a method for testing the load torque of a gas rudder, the method comprising:

[0007] Pasting strain gauges on the joystick and assembling a simulation device of the gas rudder system;

[0008] Assembling the gas rudder strain calibration system, powering on the servo mechanism, keeping the push rod of the servo mechanism in the zero position state, and gradually providing torque to the torque loading rod;

[0009] Collect the first strain value of the strain gauge varying with the loading time, and calculate the functional relationship between the first strain value and the torque;

[0010] Replace the torque loading rod with the gas rudder surface, assemble the gas rudder system, install the gas rudder system on the test bench, and install the engine, where the gas rudder surface is arranged at the engine tail nozzle;

[0011] Connect to the general control room. The general control room of the test bench includes a gas rudder control system, an ignition control system, a servo mechanism measurement and control device, and a data acquisition system. The gas rudder control system sends gas rudder commands to the gas rudder. The ignition control system controls the engine ignition and sends a unified time scale signal to the servo mechanism measurement and control device and the data acquisition system. The servo mechanism measurement and control device is used to send deflection commands to the servo mechanism and receive feedback signals, and is used to save the deflection commands and the feedback signals. The data acquisition system collects the second strain value of the strain gauge;

[0012] Wherein the servo mechanism measurement and control device sends a deflection command to the servo mechanism. The servo mechanism is powered on and the push rod of the servo mechanism moves according to the deflection command to overcome the hinge moment of the gas rudder surface;

[0013] Save the second strain value, the deflection command, and the feedback signal. According to the function of the first strain value and the torque, and simultaneously using the second strain value, calculate the gas rudder load torque.

[0014] Optionally, paste the strain gauge on the joystick and assemble the gas rudder system simulation device, including:

[0015] Determine the paste position of the strain gauge, paste 4 strain gauges on the joystick, and collect the strain value of the strain gauge by using the half-bridge lapping method;

[0016] Grind and clean the joystick to increase the surface roughness and remove the surface oxide, so that the surface of the joystick presents stripes at 45° to the paste direction of the strain gauge;

[0017] Use a scriber to mark traces on the joystick as the strain gauge positioning marks, and use medium-temperature glue to paste the strain gauge on the positioning marks;

[0018] Protect the exposed part of the strain gauge and assemble the gas rudder system simulation device.

[0019] Optionally, the step-by-step supply of torque to the torque loading rod includes:

[0020] Torque is loaded onto the torque loading rod starting from 0 N*m, with a loading step of -20 N*m, and negatively loaded to -160 N*m. Then the loading torque returns to zero, and with a loading step of +20 N*m, it is positively loaded to +160 N*m. The holding time of the torque at each loading step is 5 s.

[0021] Optionally, collecting the first strain value of the strain gauge varying with the loading time and calculating the functional relationship between the first strain value and the torque includes:

[0022] Collecting the first strain values on the 4 strain gauges on each joystick and calculating the first strain average value of the 4 first strain values, and performing linear fitting using the first strain average value and the torque to obtain the proportional function between the first strain average value and the torque.

[0023] Optionally, the ignition control system sends a unified time scale signal to the servo mechanism measurement and control device and the data acquisition system, including:

[0024] The servo mechanism measurement and control device and the data acquisition system determine the unified time scale signal as the time zero point, and determine the completion time of the gas rudder command as the time end point. The data acquisition system starts collecting the second strain value of the strain gauge from the time zero point and ends collecting the second strain value of the strain gauge from the time end point;

[0025] The servo mechanism measurement and control system starts saving the deflection command and the feedback signal from the time zero point and stops saving the deflection command and the feedback signal from the time end point.

[0026] Optionally, at the moment when the engine ignition command is issued, the signal level of the unified time scale signal rises from 0 V to the set trigger voltage. The trigger voltage is set to 10 V.

[0027] Optionally, in response to the normal operation of the data acquisition system, it is determined that the collection of the second strain value is successful.

[0028] Optionally, according to the deflection command and the feedback signal saved by the servo mechanism measurement and control device, the movement displacement information of the push rod of the servo mechanism is obtained, and further, through the spatial geometric relationship of the servo mechanism, the change situation of the output thrust of the push rod of the servo mechanism is deduced to determine the load force borne by the servo mechanism.

[0029] In a second aspect, the present application provides a gas rudder strain calibration system, including: a gas rudder system simulation device, a strain gauge, and a strain acquisition device. The gas multi-system simulation device includes: a servo mechanism, a control mechanism, and a cabin;

[0030] The cabin body is fixedly installed on the test bench and is configured to provide support for installing the servo mechanism and the control mechanism;

[0031] The servo mechanism is fixedly arranged in the cabin body, and the servo mechanism includes a telescopic push rod;

[0032] The control mechanism is movably connected to the push rod of the servo mechanism;

[0033] The control mechanism includes: a support, a first bearing, a second bearing, a rocker arm, a torque loading rod and a control rod. The support is fixedly arranged at the top of the cabin body. The support is a cavity structure and is located above the servo mechanism. The outer ring of the first bearing is fixed on the first surface of the support, and the outer ring of the second bearing is fixed on the second surface of the support. The first bearing and the second bearing are coaxial; the torque loading rod passes through the inner rings of the first bearing and the second bearing and is fixed to the inner rings of the first bearing and the second bearing; the rocker arm is arranged between the first bearing and the second bearing, and the rocker arm is fixed to the torque loading rod by a taper pin with a screwed tail. The first end of the control rod is movably connected to the rocker arm, and the second end of the control rod is rotatably connected to the lug of the push rod;

[0034] Four strain gauges are pasted on the control rod, and the strain gauges are connected to a strain acquisition device.

[0035] Optionally, a load simulation device is further included. The four load simulation devices are fixedly arranged on the test bench in an X shape. The gas rudder system simulation device is arranged in a position-adapted manner with the load simulation device. The output end of the load simulation device is fixedly connected to the torque loading rod by bolts and is configured to provide torque to the torque loading rod.

[0036] As can be seen from the above, a gas rudder strain calibration system and a test method for the load torque of a gas rudder provided by this application have the following beneficial effects:

[0037] Through the controllable torque provided by the load simulation device in the gas rudder strain calibration system, a strain gauge calibration test is carried out, so that the change of the strain value of the strain gauge under different torques can be recorded, and thus the functional relationship between the torque and the strain value can be calculated. By using the obtained functional relationship, the torque loading rod in the gas rudder strain calibration system is replaced with a gas rudder surface, and a hot test run of the engine is carried out. Thus, the magnitude of the load torque of the gas rudder can be effectively calculated through the change of the strain value of the strain gauge in the hot test run.

[0038] To ensure the accuracy of the test, in the strain gauge calibration test, the first strain values of the 4 strain gauges on each joystick are averaged and then linearly fitted with the torque to fully demonstrate the functional relationship between the strain value and the torque. Then, the engine hot test is carried out, standardizing the test process and avoiding directly using the mechanical sensor to test the load torque of the gas rudder during the engine hot test. In this case, not only does it require changing the original size of the gas rudder hot test system to provide space for installing the mechanical sensor, but also the cost of directly carrying out the engine hot test is high and the test preparation time is long. Brief Description of the Drawings

[0039] To more clearly illustrate the technical solutions in the present application or related technologies, the following will briefly introduce the drawings required for use in the embodiments or related technology descriptions. Obviously, the drawings described below are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0040] Figure 1 Schematic diagram of the gas rudder strain calibration system according to an embodiment of the present application;

[0041] Figure 2 Schematic diagram of the gas rudder system simulation device according to an embodiment of the present application;

[0042] Figure 3 Schematic diagram of the operating mechanism according to an embodiment of the present application;

[0043] Figure 4 Schematic diagram of the joystick according to an embodiment of the present application;

[0044] Figures 5a - 5d Schematic diagram of the fitting curve of the first strain value and torque of the joystick according to an embodiment of the present application;

[0045] Figure 6 Flowchart of the test method for the load torque of the gas rudder according to an embodiment of the present application;

[0046] Figure 7 Schematic diagram of the gas rudder hot test according to an embodiment of the present application;

[0047] Figures 8a - 8d Change in the load torque of the joystick according to an embodiment of the present application;

[0048] Figure 9 Schematic diagram of the motion relationship of the operating mechanism during the gas rudder hot test according to an embodiment of the present application;

[0049] Figure 10 Force analysis diagram of the operating mechanism during the gas rudder hot test according to an embodiment of the present application. Detailed Embodiments

[0050] To make the objectives, technical solutions and advantages of this application more clear and understandable, the following further elaborates on this application in detail with reference to specific embodiments and the accompanying drawings.

[0051] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of this application should have the ordinary meanings understood by those with ordinary skills in the field to which this application belongs. The "first", "second" and similar terms used in the embodiments of this application do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "linked" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0052] Such as Figure 1 、 Figure 2 、 Figure 3 、 Figure 4As shown in the figure, the present application provides a strain calibration system for a gas rudder, including: a gas rudder system simulation device 1, a strain gauge 2, and a strain acquisition device (not shown in the figure). The gas multi-system simulation device includes: a servo mechanism 11, a control mechanism 21, and a cabin 31. The cabin 31 is fixedly installed on the test bench, providing an installation platform and support for the installation of the control mechanism 21 and the servo mechanism 11. The servo mechanism 11 is fixedly arranged inside the cabin 31, and the servo mechanism 11 includes a telescopic push rod 12. The control mechanism 21 is movably connected to the push rod 12 of the servo mechanism 11. The control mechanism 21 includes: a support 211, a first bearing 212, a second bearing 213, a rocker arm 214, a torque loading rod 215, and a control rod 216. The support 211 is fixedly arranged at the top of the cabin 31. The support 211 is a cavity structure and is located above the servo mechanism 11. The outer ring of the first bearing 212 is fixed on the first surface of the support 211, and the outer ring of the second bearing 213 is fixed on the second surface of the support 211. The first bearing 212 and the second bearing 213 are coaxial. The torque loading rod 215 passes through the inner rings of the first bearing 212 and the second bearing 213 and is fixed to the inner rings of the first bearing 212 and the second bearing 213. The rocker arm 214 is arranged between the first bearing 212 and the second bearing 213, and the rocker arm 214 is fixed on the torque loading rod 215 through a taper pin with a threaded tail. The first end of the control rod 216 is movably connected to the rocker arm 214, and the second end of the control rod 216 is rotatably connected to the lug of the push rod 12. First, the support 211 is fixed to the cabin 31 through bolts. The support 211 is a cavity structure. The first bearing 212 and the second bearing 213 are respectively installed on the opposite sides of the support 211. Then, the torque loading rod 215 passes through the inner ring of the second bearing 213, the rocker arm 214, and the inner ring of the second bearing 213 and is fixedly connected to the inner rings of the first bearing 212 and the second bearing 213. At the same time, the rocker arm 214 is fixed on the torque loading rod 215 through a taper pin with a threaded tail. In this way, the torque loading rod 215 can rotate through the first bearing 212 and the second bearing 213, and the two ends of the control rod 216 are respectively rotatably connected to the rocker arm 214 and the push rod 12. Here, it should be noted that no matter whether the control rod 216 rotates along the end connected to the rocker arm 214 or along the end connected to the push rod 12, it always rotates in the same plane.

[0053] Four strain gauges 2 are pasted on the control rod 216. The strain gauges 2 are electrically connected to the strain acquisition device. Then, a torque value is applied to the torque loading rod 215, and the strain values of the strain gauges 2 on the control rod 216 change. The relationship between the torque and the strain values can be calculated. The four strain gauges 2 can be more accurate and reduce the error caused by the strain value of a single strain gauge 2. Pasting four strain gauges 2 provides four strain values for full verification, and the strain acquisition device is used to collect the strain values.

[0054] It includes a load simulation device 3. Four load simulation devices 3 are fixed on the test bench in an X shape. The gas rudder system simulation device 1 is arranged in a position-adapted manner with the load simulation device 3. The output end of the load simulation device 3 is fixedly connected to the torque loading rod 215 through bolts and is configured to provide torque to the torque loading rod 215. In order to obtain accurate torque, a load simulation device 3 is provided to provide torque. At the same time, when four load simulation devices 3 are fixed on the test bench in an X shape, four groups of tests can be carried out simultaneously, and the strain values of 16 strain gauges 2 on 4 joysticks 216 can be measured with respect to the change of torque, providing sufficient demonstration.

[0055] In the second aspect of the present application, as Figure 6 shown, a method for testing the load torque of a gas rudder is provided, including the following steps:

[0056] S1. Paste strain gauges on the joystick and assemble the gas rudder system simulation device;

[0057] S2. Assemble the gas rudder strain calibration system, power on the servo mechanism, keep the push rod of the servo mechanism in the zero position state, and gradually provide torque to the torque loading rod;

[0058] S3. Collect the first strain value of the strain gauge changing with the loading time, and calculate the proportional function between the first strain value and the torque value;

[0059] S4. Replace the torque loading rod with the gas rudder surface, assemble the gas rudder system, install the gas rudder system on the test stand, install the engine, and arrange the gas rudder surface at the engine tail nozzle;

[0060] S5. Connect to the general control room. The test stand general control room includes a gas rudder control system, an ignition control system, a servo mechanism measurement and control device, and a data acquisition system. The gas rudder control system sends gas rudder commands to the gas rudder. The ignition control system controls the engine ignition and sends a unified time scale signal to the servo mechanism measurement and control device and the data acquisition system. The servo mechanism measurement and control device is used to send deflection commands to the servo mechanism and receive feedback signals, and is used to save the deflection commands and the feedback signals. The data acquisition system collects the second strain value of the strain gauge;

[0061] Wherein the servo mechanism measurement and control device sends a deflection command to the servo mechanism, the servo mechanism is powered on, and the push rod of the servo mechanism moves according to the deflection command to overcome the hinge moment of the gas rudder surface;

[0062] S6. Save the second strain value, the deflection command, and the feedback signal, and calculate the gas rudder load torque according to the first strain value and the torque function, and simultaneously use the second strain value.

[0063] In step S1, the strain gauge attachment locations must first be determined. To eliminate the uncertainty associated with strain gauge attachment locations and manual manipulation in subsequent strain-to-torque test results, multiple sets of strain gauges are attached to the joysticks for full verification. Four strain gauges are placed on each joystick, and a bridge-type lap joint is used to eliminate the effects of temperature on inaccurate strain measurements.

[0064] In some embodiments, the joystick surface is polished with 240-grit sandpaper to increase surface roughness and remove oxides from the joystick surface. The joystick surface is then polished with 100-grit sandpaper to create cross-stripes at a 45-degree angle to the strain gauge placement direction. After polishing, the joystick placement area is cleaned with alcohol or acetone to remove sand and impurities from the surface. This removes oxides from the joystick surface and impurities that may affect the strain gauge's strain measurement, resulting in more accurate measurement results. Sanding the cross-stripes with sandpaper also helps ensure a more secure attachment of the strain gauge.

[0065] Then, use a scriber to slide out a positioning mark on the polished and cleaned position of the joystick, and then use medium-temperature glue to stick the strain gauge on the joystick.

[0066] Protect the exposed areas of the strain gauge and assemble the gas rudder system simulator. To ensure proper operation and protect the strain gauge from external interference, the already attached strain gauge is protected. G-704 silicone rubber can be used to cover the strain gauge for improved strain measurement accuracy. Once all preparations are complete, assemble the gas rudder system simulator.

[0067] In step S2, the gas rudder strain calibration system is assembled. According to the installation position of the load simulation device, four sets of gas rudder system simulation devices can be installed respectively, so that the strain values of the four strain gauges on each joystick, a total of 16 strain gauges, can be collected. During this process, the servo mechanism is powered on, the push rod is maintained in the zero position state of the servo mechanism, and the load simulation device applies torque to the torque loading rod. In some embodiments, the torque starts from 0 N*m, with -20 N*m as a loading step, and the load simulation device applies torque to the torque loading rod in the negative direction until it is loaded to -160 N*m. Then the torque applied by the load simulation device returns to zero, and then +20 N*m is used as a loading step, and it is positively loaded to +160 N*m. It is necessary to maintain each loading step for 5 seconds to ensure the stability of the strain value of the strain gauge and the accuracy of the measurement. Through the above-mentioned step-by-step torque loading, the change value of the strain value of each strain gauge with the loading time can be directly obtained from the strain acquisition device.

[0068] Here, it should be noted that in the above test for measuring strain values, it is necessary to ensure that the strain values of a total of 16 strain gauges on the four groups of joysticks can be collected normally. If there is a path where the strain value cannot be collected, the corresponding strain gauge and connection line need to be checked. If necessary, the connection line is re-welded or a new strain gauge is re-pasted.

[0069] In step S3, the first strain value of the strain gauge changing with the loading time is collected, and the functional relationship Y = KX between the first strain value and the torque is calculated, where Y represents the strain value, K represents the coefficient, and X represents the torque. The first strain value here refers to the strain value corresponding to the strain gauge when the load simulation device applies torque to the torque loading rod.

[0070] Here, since the positions of the 4 strain gauges on each joystick are different, there will be a certain difference in the measured values of the first strain value of each strain gauge. Therefore, when processing the first strain value, the 4 first strain values on each joystick are averaged and then linearly fitted with the torque to obtain the proportional relationship between the first strain mean values of the 4 joysticks and the torque for fitting, as Figures 5a - 5d shown, which respectively represent the linear relationships between the torque and the first strain mean values on the four joysticks. Through data fitting, the functional relationship between the first strain mean values and the torque on the four joysticks is Y i = K i X, where Y i represents the first strain mean value of the i-th joystick, X represents the torque, and K i represents the coefficient, i = 1, 2, 3, 4. As shown in Table 1 below

[0071] Joystick number Fitting equation Coefficient Remarks 1 <![CDATA[Y1 = 1.8671X]]> 0.9995 / 2 <![CDATA[Y2 = 1.7846X]]> 1.0000 / 3 <![CDATA[Y3 = 1.8734X]]> 1.0000 / 4 <![CDATA[Y4 = 1.8590X]]> 1.0000 /

[0072] Table 1

[0073] As can be seen from Table 1, the linear relationship between the first strain mean values of the four joysticks and the torque is relatively high, and at the same time, its linear proportional coefficient is determined to prepare for the subsequent hot test of the gas rudder.

[0074] In step S4, the gas rudder surface is replaced with the torque loading rod in the gas rudder strain calibration system to assemble the gas rudder system 301. Among them, the joystick and the strain gauge pasted on it remain in the state of measuring the first strain value as described above. The gas rudder system 301 is assembled on the test bench in the test workshop according to the standards of the hot test of the engine 305 together with the above servo mechanism, cabin, etc.

[0075] In step S5, as Figure 7As shown in the figure, it is connected to the master control room. Here, the gas rudder control system and the ignition control system 302 are placed in the control room, the servo mechanism measurement and control device 303 and the data acquisition system 304 are placed in the test room. The servo mechanism measurement and control device is connected to the servo mechanism through a cable to control the servo mechanism to deflect according to the deflection command. The data acquisition system 304 is connected to the strain gauge through a data acquisition lead to collect the second strain value of the strain gauge in real time. Here, since the hot test environment of the engine 305 is relatively harsh, in order to avoid electromagnetic interference and the erosion of the engine 305 jet, the data acquisition lead is wound with copper foil and then wrapped and protected with asbestos tape. The ignition control device is connected to the engine 305 to send an ignition signal to control the ignition of the engine 305. At the same time, the control point or device is connected to the servo mechanism measurement and control device 303 and the data acquisition system 304 to send a unified time scale signal of 10V voltage to the servo mechanism measurement and control device 303 and the data acquisition system 304. It should be noted that the unified time scale signal sends a unified time scale signal to the servo mechanism measurement and control device 303 and the data acquisition system 304 at the moment when the ignition control device issues an ignition command. When the level of the unified time scale signal rises from 0V to the trigger voltage of 10V, the servo mechanism measurement and control device 303 and the data acquisition system 304 start to work. The servo mechanism is powered on and starts to move according to the command of the servo mechanism measurement and control device 303. The gas rudder control system sends a command to control the gas rudder surface to deflect according to the command in the engine 305 jet, and the data acquisition system 304 collects the second strain value of the strain gauge here.

[0076] Here, after the hot test of the engine 305 is completed, if it is detected that the data acquisition system 304 is working normally and the strain data is collected normally, it is determined that the second strain value collection test is successful, and the second strain value data, the deflection command of the servo mechanism measurement and control system, and the feedback signal of the servo mechanism to the servo mechanism measurement and control system are saved.

[0077] In step S6, the 16 second strain values of the four joysticks are processed and analyzed. In the above-mentioned hot test of the engine 305, the unified time scale signal of 10V voltage is used as the time zero point, and the data acquisition system 304 and the servo mechanism measurement and control system start to collect data, send a deflection command to the servo mechanism, etc. The data collection is stopped at the time when the deflection command of the gas rudder of the gas rudder control system is completed as the end point, and the second strain value data between the time zero point and the time end point is intercepted for subsequent analysis.

[0078] The average value of the 4 second strain values on each joystick is denoted as Y i * , and the load torque of the gas rudder at the corresponding time is denoted as M i , then Y i * = M i K i , that is, Mi = Y i * / K i . By calculation, the accurate result of the load torque of the gas rudder can be obtained.

[0079] As Figures 8a - 8d shown, it is a schematic diagram of the change of the load torque of the gas rudder over time. Here, the accurate result of the load torque of the gas rudder is measured. Compared with the method of installing a mechanical sensor to measure the load torque of the gas rudder in the hot test of the engine 305 in the related technology, it is not necessary to change the original size of the gas rudder system in the engine hot test to provide an installation space for the mechanical sensor.

[0080] In some embodiments, after assembling the gas rudder system, in the spatial relationship of the operating mechanism, the push rod, the operating rod, and the rocker arm of the servo mechanism move in the same plane. Refer to Figure 2 , Figure 3 , Figure 9 , in Figure 9 , taking the linear motion direction of the push rod as the x-direction and its vertical direction as the y-direction, the intersection of the center C of the rudder axis of the gas rudder along the x-direction and the y-direction is the O point. Here, a coordinate system x - O - y is established. The hinge point where the push rod is rotationally connected to the operating rod is B, the length of the operating rod AB is L1, the length of the rocker arm BC is L2, the distance between the center C of the rudder axis of the gas rudder and the O point is L3, and the A point is defined as the zero point of the operating mechanism. A l and A r are the positions where the push rod moves left and right relative to the A point respectively. The distance between the center C of the rudder axis of the gas rudder and the linear motion direction of the push rod is a, the linear displacement of the push rod is represented by S(t), which can be obtained through the feedback signal of the servo mechanism to the servo mechanism measurement and control system, and the angle between the operating rod and the motion direction of the push rod is represented by θ1.

[0081] Through Figure 9 the set relationship in, the expression of θ1 can be obtained:

[0082]

[0083] Among them then θ1 is:

[0084]

[0085] In Figure 10 , F1 is the axial force of the operating rod, and F2 and F3 are the tangential force and axial force received by the rocker arm respectively.

[0086] The relationship between the force on the operating rod and the thrust F of the push rod of the servo mechanism t is:

[0087] F1 = Ft × cosθ1 (3)

[0088] In the above first strain value acquisition test, a torque value is provided to point C, while the operating mechanism is always in Figure 9 the ABC state; through geometric relationships, the relationship between torque and the force on the joystick can be obtained:

[0089] M = F1 × a (4)

[0090] During the process of gradually increasing the torque, the joystick only bears tensile and compressive stresses, so the relationship between the force on the joystick and the first strain value is:

[0091] F1 = p·Y (5)

[0092] In formula (5), p is the proportionality coefficient. Through formula (5) and formula (6), the proportionality coefficient can be obtained:

[0093] p = M / (a·Y) = 1 / (K·d) (6)

[0094] When testing the second strain value during the engine hot test run, the obtained second strain value is denoted as Y1 * , then the force F1 on the joystick * is:

[0095] F1 * = p·Y1 * (7)

[0096] Then when the operating mechanism moves, the push rod thrust is:

[0097] F t * = F1 * / cosθ1 (8)

[0098] Combining formula (2), formula (6) and formula (7), formula (8) can be further expressed as:

[0099]

[0100] It can be seen from formula (9) that by determining the time zero point through a 10V unified time scale signal, obtaining the push rod movement displacement according to the feedback signal of the servo mechanism, and completing the data processing of the second strain value and the gas rudder load torque, the change situation of the push rod output thrust of the servo mechanism can be obtained. Based on the change situation of the output thrust, it provides a basis for the design of the gas rudder servo mechanism.

[0101] This application makes the test of the gas rudder load torque more accurate by standardizing various aspects such as the test steps, test process, experimental technology, and data processing.

[0102] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present application (including the claims) is limited to these examples; within the context of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the embodiments of the present application as described above, and for the sake of brevity they are not provided in detail.

[0103] In addition, for simplicity of explanation and discussion, and in order not to make the embodiments of the present application difficult to understand, the well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Further, the devices may be shown in block diagram form in order to avoid making the embodiments of the present application difficult to understand, and this also takes into account the fact that the details of the implementation of these block diagram devices are highly dependent on the platform on which the embodiments of the present application are to be implemented (i.e., these details should be fully within the understanding of those skilled in the art). In cases where specific details (such as circuits) are set forth to describe exemplary embodiments of the present application, it will be apparent to those skilled in the art that the embodiments of the present application can be implemented without these specific details or with variations of these specific details. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0104] Although the present application has been described in connection with specific embodiments of the present application, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description.

[0105] The embodiments of the present application are intended to cover all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. A gas rudder strain calibration system, characterized in that, Comprising: A gas rudder system simulation device, strain gauges, and a strain acquisition device. The gas rudder system simulation device includes: a servo mechanism, a steering mechanism, and a cabin body; The cabin body is fixedly installed on a test bench and is configured to provide support for installing the servo mechanism and the steering mechanism; The servo mechanism is fixedly arranged inside the cabin body, and the servo mechanism includes a telescopic push rod; The steering mechanism is movably connected to the push rod of the servo mechanism; The steering mechanism includes: a support, a first bearing, a second bearing, a rocker arm, a torque loading rod, and a control rod. The support is fixedly arranged at the top of the cabin body. The support is a cavity structure and is located above the servo mechanism. The outer ring of the first bearing is fixed on the first surface of the support, and the outer ring of the second bearing is fixed on the second surface of the support. The first bearing and the second bearing are coaxial; the torque loading rod passes through the inner rings of the first bearing and the second bearing and is fixed to the inner rings of the first bearing and the second bearing; the rocker arm is arranged between the first bearing and the second bearing, and the rocker arm is fixed to the torque loading rod by a taper pin with a threaded tail. The first end of the control rod is movably connected to the rocker arm, and the second end of the control rod is rotatably connected to the lug of the push rod; 4 strain gauges are pasted on the control rod, and the strain gauges are connected to the strain acquisition device; a load simulation device is further included. The four load simulation devices are fixed on the test bench in an X shape. The gas rudder system simulation device is arranged in a position-adapted manner with the load simulation device. The output end of the load simulation device is fixedly connected to the torque loading rod by a bolt and is configured to provide torque to the torque loading rod.

2. A test method for the load torque of a gas rudder, characterized in that Applicable to the gas rudder strain calibration system according to claim 1, the method includes: Pasting strain gauges on the control rod and assembling the gas rudder system simulation device; Assembling the gas rudder strain calibration system, powering on the servo mechanism, keeping the push rod of the servo mechanism in the zero position state, and gradually providing torque to the torque loading rod; Collecting the first strain value of the strain gauges changing with the loading time, and calculating the functional relationship between the first strain value and the torque; Replacing the torque loading rod with a gas rudder surface, assembling the gas rudder system, installing the gas rudder system on the test stand, installing an engine, and the gas rudder surface is arranged at the engine tail nozzle; Connecting to the general control room. The test stand general control room includes a gas rudder control system, an ignition control system, a servo mechanism measurement and control device, and a data acquisition system. The gas rudder control system sends gas rudder commands to the gas rudder. The ignition control system controls the engine ignition and sends a unified time scale signal to the servo mechanism measurement and control device and the data acquisition system. The servo mechanism measurement and control device is used to send deflection commands to the servo mechanism and receive feedback signals, and is used to save the deflection commands and the feedback signals. The data acquisition system collects the second strain value of the strain gauges; Wherein the servo mechanism measurement and control device sends a deflection command to the servo mechanism, the servo mechanism is powered on, and the push rod of the servo mechanism moves according to the deflection command to overcome the gas rudder load torque; Save the second strain value, the deflection command, and the feedback signal, and calculate the load moment of the gas rudder according to the functional relationship between the first strain value and the torque, while using the second strain value.

3. The method according to claim 2, wherein Paste strain gauges on the joystick and assemble the gas rudder system simulation device, including: Determine the paste positions of the strain gauges, paste 4 strain gauges on the joystick, and collect the strain values of the strain gauges in a half-bridge connection mode. Grind and clean the joystick to increase the surface roughness and remove the surface oxide, so that the surface of the joystick presents stripes at 45° to the paste direction of the strain gauges. Use a scriber to mark traces on the joystick as the positioning marks for the strain gauges, and use medium-temperature glue to paste the strain gauges on the positioning marks. Protect the exposed parts of the strain gauges and assemble the gas rudder system simulation device.

4. The method according to claim 2, wherein Gradually apply torque to the torque loading rod, including: Apply torque to the torque loading rod starting from and using as a loading step, load negatively until . Then return the applied torque to zero, and using as a loading step, load positively until ; wherein the holding time of the torque at each loading step is 5 s.

5. The method according to claim 4, wherein Collect the first strain value of the strain gauges varying with the loading time, and calculate the functional relationship between the first strain value and the torque, including: Collect the first strain values of the 4 strain gauges on each joystick, calculate the first strain mean value of the 4 first strain values, and perform linear fitting on the first strain mean value and the torque to obtain the proportional function between the first strain mean value and the torque.

6. The method according to claim 5, wherein The ignition control system sends a unified time scale signal to the servo mechanism measurement and control device and the data acquisition system, including: The servo mechanism measurement and control device and the data acquisition system determine the unified time scale signal as the time zero point, determine the completion time of the gas rudder command as the time end point, and the data acquisition system starts collecting the second strain value of the strain gauges from the time zero point and ends collecting the second strain value of the strain gauges from the time end point. The servo mechanism measurement and control device starts saving the deflection command and the feedback signal from the time zero point and stops saving the deflection command and the feedback signal from the time end point.

7. The method according to claim 3, characterized in that, At the moment when the engine ignition command is issued, the signal level of the unified time scale signal rises from 0V to the set trigger voltage; where the trigger voltage is set to 10V.

8. The method according to claim 6, characterized in that, In response to the normal operation of the data acquisition system, it is determined that the acquisition of the second strain value is successful.

9. The method according to claim 6, wherein According to the deflection command and the feedback signal saved by the servo mechanism measurement and control device, obtain the movement displacement information of the push rod of the servo mechanism, and further deduce the change of the output thrust of the push rod of the servo mechanism through the spatial geometric relationship of the servo mechanism to determine the load force borne by the servo mechanism.

Images