High sea state landing gear limit performance simulation device and method

Abstract

The application belongs to the technical field of helicopter test, and particularly relates to a high sea state landing gear limiting performance simulation device, wherein a main landing gear test piece is completely same as a real main landing gear, a rocker arm of the main landing gear test piece is installed on a main test bench through a main rocker arm clamp joint, a buffer of the main landing gear test piece is installed on the main test bench through a main buffer clamp joint, and a main limiting device is installed on the buffer of the main landing gear test piece to limit the stroke of the buffer; an axle of the rocker arm of the main landing gear test piece is provided with a main loading joint, a main loading assembly loads the main landing gear test piece through the main loading joint; the main loading assembly and a tail loading assembly load the main landing gear test piece and a tail landing gear test piece respectively to simulate the loading condition of a helicopter when parked on a ship, so as to test the limiting performance of the main limiting device and a tail limiting device.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of helicopter test, and particularly relates to a high-sea-condition landing gear limiting performance simulation device and method. BACKGROUND

[0002] When a ship sails on the sea or is at rest, a helicopter parked on the ship will be in a rocking state under the disturbance of sea waves and sea winds, and a buffer of a landing gear of the helicopter has the functions of absorbing energy and reducing impact load, and is designed to be capable of telescopic movement, that is, a relative movement along an axis between an outer cylinder and a piston rod (for example, as shown in FIG. 1). Figure 1 If the helicopter is tilted or impacted due to the telescopic movement of the landing gear, the use of the helicopter on the ship will be dangerous, and a telescopic limiter is usually installed on the landing gear on the ship to limit the telescopic movement of the landing gear, so that the length of the buffer of the landing gear of the helicopter is kept unchanged or changes in a small range.

[0003] At present, the limiting test of the helicopter on the ship under high sea conditions is based on a real shipborne platform, and there is no mature test device and test method for verifying the function and performance index of the limiting ability of the landing gear of the shipborne helicopter in a laboratory environment on land. SUMMARY

[0004] The application aims to overcome the deficiencies of the prior art and realize the laboratory test of the helicopter landing gear limiting simulation, and provides a high-sea-condition landing gear limiting performance simulation device and method, which provides a land-based verification basis for judging whether the shipborne helicopter can be applied under high sea conditions.

[0005] The technical scheme of the application is as follows.

[0006] A high-sea-condition landing gear limiting performance simulation device comprises a main landing gear test piece, a main landing gear limiter, a main landing gear rocker arm clamp joint, a main landing gear buffer clamp joint, a main landing gear test bench, a main landing gear loading assembly, a tail landing gear test piece, a tail landing gear limiter, a tail landing gear test bench and a tail landing gear loading assembly.

[0007] The main landing gear test piece is completely identical to the real main landing gear, the rocker arm of the main landing gear test piece is installed on the main test bench through the main rocker arm clamp joint, the buffer of the main landing gear test piece is installed on the main test bench through the main buffer clamp joint, the main limiter is installed on the buffer of the main landing gear test piece to limit the stroke of the buffer; the axle of the rocker arm of the main landing gear test piece is provided with a main loading joint, and the main loading assembly loads the main landing gear test piece through the main loading joint;

[0008] The tail landing gear test piece is completely identical to the real tail landing gear, the buffer of the tail landing gear test piece is installed on the tail test bench, and the tail limiter is installed on the buffer of the tail landing gear test piece to limit the stroke of the buffer; the left and right ends of the axle of the tail landing gear test piece are provided with tail loading joints, and the tail loading assembly loads the tail landing gear test piece through the tail loading joints;

[0009] The main and tail loading assemblies load the main and tail landing gear test pieces respectively to simulate the loading condition of the helicopter when parked on the ship, so as to test the limiting performance of the main and tail limiters.

[0010] Further, the main loading joint comprises one or more of X, Y and Z direction loading joints; and the main loading assembly comprises one or more of X, Y and Z direction actuating cylinders fixed on the main actuating force platform.

[0011] Further, the tail loading joint comprises two Z direction loading joints arranged on the left and right axles, and the tail loading assembly comprises two tail Z direction actuating cylinders for loading the two Z direction loading joints on the left and right axles.

[0012] Further, the device further comprises a controller; the controller controls the main and tail loading assemblies to test the main and tail landing gear test pieces with a trigonometric function wave load.

[0013] Further, one end of the main limiter is fixed on the outer cylinder of the buffer of the main landing gear test piece, and the other end is fixed on the telescopic rod of the buffer of the main landing gear test piece, and the maximum displacement of the telescopic rod relative to the buffer outer cylinder is limited by the elastic deformation of the main limiter;

[0014] The tail limiter has a structure similar to that of the main limiter.

[0015] A high sea state landing gear limiting performance simulation method, the method is implemented by the device, and the method comprises the following steps:

[0016] Step 1: install the main and tail landing gear test pieces on the main and tail test benches respectively;

[0017] Step two: install the main landing gear limiters and the tail landing gear limiters;

[0018] Step three: install displacement sensors between the outer cylinder of the main landing gear shock absorber and the piston rod, and between the outer cylinder of the tail landing gear shock absorber and the piston rod;

[0019] Step four: select test scenarios, determine the maximum and minimum loads of the main landing gear in X, Y and Z directions under tension and compression, and determine the maximum and minimum loads of the tail landing gear in Z direction under tension and compression;

[0020] Step five: determine the loading frequency;

[0021] Step six: generate a trigonometric function waveform according to the load extremes determined in step four and the loading frequency determined in step five, and control the main landing gear loading assembly and the tail landing gear loading assembly to load the main landing gear test piece and the tail landing gear test piece according to the trigonometric function waveform;

[0022] Step seven: collect displacement sensor data installed on the main landing gear and the tail landing gear, and compare the displacement sensor data with theoretical data, if greater than the theoretical data, it is determined that the corresponding limiter has insufficient limiting performance, otherwise it is determined that the corresponding limiter has good limiting performance.

[0023] Further, in step two, the process of installing the main or tail limiters is as follows:

[0024] Empty the fluid in the high-pressure cavity and the low-pressure cavity of the main or tail landing gear test piece;

[0025] Adjust the piston rod extension length of the main or tail landing gear test piece shock absorber, so that the piston rod extension length is equal to the piston rod extension length when the helicopter is parked on the ship;

[0026] Install the main or tail limiters;

[0027] Fill the fluid in the high-pressure cavity and the low-pressure cavity of the main or tail landing gear test piece so that the pressure in the high-pressure cavity and the low-pressure cavity matches the piston rod extension.

[0028] Further, in step four, the test scenarios include: hangar mooring, deck mooring, and transfer.

[0029] Further, in the step five, the loading frequency is determined by the following process: according to the most severe sea condition of the sea area where the ship sails, the sea wave data is collected to obtain the time required for the ship to pitch or roll one complete amplitude, and the time length is used as the time in a loading cycle; and according to the statistical normal distribution of the most probable time length of the severe sea wave, the time length is divided by the time required for the ship to pitch or roll one complete amplitude, and the time length is used as the test frequency.

[0030] Further, in the step seven, the main landing gear theoretical data is calculated by the following process:

[0031] According to the main landing gear span length L and the angle a when the overturning risk occurs, the main landing gear length change limit length K is calculated; the formula is as follows:

[0032] K=(L / 2)tan(a);

[0033] a is the angle when the overturning risk occurs;

[0034] The tail landing gear theoretical data is calculated by the following process:

[0035] According to the tail landing gear and the nose lowest point span length S and the angle b when the nose lowest point touches the ground, and the main landing gear installation position, the limit length N is calculated; the formula is as follows:

[0036] N=Stan(b);

[0037] B is the angle when the nose lowest point touches the ground.

[0038] The beneficial technical effects of the present application are:

[0039] 1. The test device can realize triangular, rectangular and sinusoidal wave loading, and the loading rate range is 0.001-3mm / s; convenient adjustment;

[0040] 2. The problem of spending a large amount of manpower, material resources and special ship platform for sea-borne helicopter test is solved, and the test efficiency and economy are improved;

[0041] 3. The whole test method is operated in a land test room, and does not need a ship platform and marine environment, the test period is shortened, and the comprehensive verification cost is saved;

[0042] 4. The present application can simulate the loading test of the sea-borne helicopter under the influence of wind load, wave load and other cyclic load effects in a land test room. By adjusting and changing the load amplitude, frequency and other conditions, different loading modes are output to simulate the action of the helicopter landing gear under different working conditions;

[0043] 5. The land-based test device can simulate the dynamic working condition of the helicopter in the high sea state of the ship system, and the data measured by the test sensor can directly determine whether the maximum speed, acceleration, reaction time and other performances of the helicopter in the high sea state of the ship satisfy the performance index of the high sea state, thereby providing a strong basis for determining whether the helicopter has sufficient landing gear limiting capacity on the ship, and ensuring the reliability and safety of the helicopter in the sea operation of the ship;

[0044] 6. The test device and the test operation method are simple and suitable for general practitioners. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 is a schematic view of axial movement of the buffer;

[0046] Figure 2 is a schematic view of load variation;

[0047] Figure 3 is a schematic view of installation of the main landing gear test piece;

[0048] Figure 4 is a schematic view of installation of the tail landing gear test piece;

[0049] Figure 5 is an enlarged view of A;

[0050] Figure 6 is an enlarged view of B;

[0051] Figure 7 is a tail tilt schematic view;

[0052] Figure 8 is a pitch schematic view;

[0053] Number Description: 1. Main landing gear test piece, 2. Main landing gear limiter, 3. Main landing gear rocker arm clamp joint, 4. Main landing gear buffer clamp joint, 5. Main landing gear test bench, 6. Main landing gear Y-direction hydraulic actuator cylinder, 7. Main landing gear Z-direction hydraulic actuator cylinder, 8. Main landing gear actuator bearing platform, 9. Tail landing gear test piece, 10. Tail landing gear limiter, 11. Tail landing gear test bench, 12. Tail landing gear combined actuator cylinder, 13. Tail landing gear actuator bearing platform, 14. Main landing gear Y-direction loading joint, 15. Main landing gear Z-direction loading joint, 16. Main landing gear Z-direction loading pull joint, 17. Tail landing gear loading joint, 18. Tail landing gear loading pull joint, 19. Main landing gear buffer strut outer cylinder, 20. Main landing gear piston rod, 21. Tail landing gear buffer strut outer cylinder, 22. Piston rod. DETAILED DESCRIPTION

[0054] Clearly, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present application.

[0055] The device and method construct a roll and pitch onshore laboratory test load simulating ship wave disturbance through a sine periodic loading method in a laboratory, perform active periodic loading onshore test of the helicopter landing gear, and process and analyze data measured based on sensors, so as to intuitively determine whether the small deformation displacement amount, acceleration and other performances of the left and right main landing gears and the tail landing gear of the helicopter after being limited by the limiter meet the performance index of working in high sea conditions.

[0056] A high-sea-condition landing gear limiting performance simulation device, comprising: a main landing gear test piece 1, a main landing limiter 2, a main landing rocker clamp joint 3, a main landing buffer clamp joint 4, a main landing test bench 5, a main landing Y-direction hydraulic actuator cylinder 6, a main landing Z-direction hydraulic actuator cylinder 7, a main landing actuating bearing platform 8, a tail landing gear test piece 9, a tail landing limiter 10, a tail landing test bench 11, a tail landing combined actuator cylinder 12, a tail landing actuating bearing platform 13, a main landing Y-direction loading joint 14, a main landing Z-direction loading joint 15, a main landing Z-direction loading opposite-pull joint 16, a tail landing loading joint 17, and a tail landing loading opposite-pull joint 18; the main landing gear test piece 1 is installed on the main landing test bench 5 through the main landing rocker clamp joint 3 and the main landing buffer clamp joint 4, the main landing Y-direction loading joint 14, the main landing Z-direction loading joint 15, and the main landing Z-direction loading opposite-pull joint 16 are installed on the main landing gear test piece 1, Y-direction load is loaded on the main landing Y-direction loading joint 14 through the Y-direction hydraulic actuator cylinder 6, so that the Y-direction load is applied to the main landing gear, Z-direction load is loaded on the main landing Z-direction loading joint 15 through the Z-direction hydraulic actuator cylinder 7, so that the Z-direction load is applied to the main landing gear, and the Y-direction hydraulic actuator cylinder 6 and the Z-direction hydraulic actuator cylinder 7 are installed on the main landing actuating bearing platform 8; the tail landing gear test piece 9 is fixed on the tail landing test bench 11 through fastening bolts, the tail landing loading joint 17 and the tail landing loading opposite-pull joint 18 are installed on the tail landing gear test 9, Z-direction load is loaded on the tail landing loading joint 17 through the combined actuator cylinder 12, so that the Z-direction load is applied to the tail landing gear test piece 9, and the combined actuator cylinder 12 is installed on the tail landing actuating bearing platform 13.

[0057] The application discloses a high-sea-state landing gear limiting performance simulation method, which comprises the following steps: firstly, a physical test installation platform is established according to the actual situation on the machine; then, the state parameters of a test piece are set to form a parameter-adjustable high-sea-state telescopic limiting motion test platform; the motion state process of the landing gear under the action of the sea state is simulated by setting a loading cycle by using a trigonometric function, and the landing gear is loaded; the length change of the piston rod of the main landing gear and the tail landing gear is tested according to a sensor system, and the test data are transmitted to a computer controller to record the test data and analyze the test data. The high-sea-state landing gear telescopic limiting simulation motion test is realized, and theoretical and technical support is provided for the telescopic limiting capability of the high-sea-state landing gear.

[0058] The trigonometric function waveform takes the maximum load under the corresponding working condition as a wave crest and the minimum load as a wave trough; the ship pitching and rolling fluctuation cycle is the loading cycle, and the ship pitching and rolling fluctuation cycle can be obtained according to the sea state of the sea area where the ship sails, and the ship's swing and fluctuation cycle and frequency can be obtained according to the sea wave data.

[0059] The specific test steps, namely the test method, are as follows:

[0060] (1) The test piece is installed in the following order:

[0061] a) The main landing arm clamp joint 3 and the main landing buffer clamp joint 4 are fixed on the test bench floor, and the main landing gear test piece is fixed; the relative spatial position relationship of the main landing arm clamp joint 3 and the main landing buffer clamp joint 4 is adjusted, so that the main landing gear installation is consistent with the actual situation of the helicopter (that is, the installation angle of the main landing gear buffer support and the arm, the distance between the buffer support and the arm mounting point and the like reach specific values);

[0062] b) The main landing Y-direction hydraulic actuator 6 and the main landing Z-direction hydraulic actuator 7 are fixed on the main landing force bearing platform 8, and the main landing gear test piece is loaded by the hydraulic actuator;

[0063] c) The tail landing gear test piece is installed on the tail test bench 11 through fastening bolts;

[0064] d) The tail landing gear test piece is loaded by the tail landing gear actuator 12 fixed on the force bearing platform.

[0065] (2) The test piece parameters are adjusted in the following order:

[0066] a) The high-pressure cavity and the low-pressure cavity of the main landing gear test piece are discharged;

[0067] b) The piston rod extension amount of the main landing gear test piece is adjusted, so that the piston rod extension length under the actual shutdown weight state is obtained;

[0068] c) The main landing telescopic limiter is installed;

[0069] d) According to the given parameters (the high-pressure cavity air pressure value of the main landing gear test piece, the low-pressure cavity air pressure value of the main landing gear test piece), inflate the high-pressure cavity and the low-pressure cavity of the main landing gear test piece to the pressure value corresponding to the piston rod extension amount in step b);

[0070] e) Deflate the high-pressure cavity and the low-pressure cavity of the tail landing gear test piece;

[0071] f) Adjust the piston rod extension amount of the tail landing gear test piece;

[0072] g) Install the tail landing telescopic limiter;

[0073] h) According to the given parameters (the high-pressure cavity air pressure value of the tail landing gear test piece, the low-pressure cavity air pressure value of the tail landing gear test piece), inflate the high-pressure cavity and the low-pressure cavity of the tail landing gear test piece to the pressure value corresponding to the piston rod extension amount in step f);

[0074] (3) Install displacement sensors between the main landing gear buffer strut outer cylinder 19 and the piston rod 20, and between the tail landing gear buffer strut outer cylinder 21 and the piston rod 22;

[0075] (4) According to the use scenarios: such as hangar mooring, deck mooring, transfer, etc. Determine the maximum load and the minimum load of the main landing gear in six directions: P1x + _max, P1x + _min, P1x - _max, P1x - _min, P1y + _max, P1y + _min, P1y - _max, P1y - _min, P1z + _max, P1z + _min, P1z - _max, P1z - _min; and the maximum load and the minimum load of the tail landing gear in six directions: P2x + _max, P2x + _min, P2x - _max, P2x - _min, P2y + _max, P2y + _min, P2y - _max, P2y - _min, P2z + _max, P2z + _min, P2z - _max, P2z -_min; the above load can be calculated according to the force analysis of the landing gear of the helicopter after being moored on the ship and the force analysis of the landing gear during the transfer.

[0076] P1x + _max represents the maximum value of the main landing gear X-axis positive direction;

[0077] P1x + _min represents the minimum value of the main landing gear X-axis positive direction;

[0078] P1x - _max represents the maximum value of the main landing gear X-axis negative direction;

[0079] P1x - _min represents the minimum value of the main landing gear X-axis negative direction;

[0080] P1y + _max represents the maximum value of the main landing gear Y-axis positive direction;

[0081] P1y + _min represents the minimum value of the main landing gear Y-axis positive direction;

[0082] P1y - _max represents the maximum value of the main landing gear Y-axis negative direction;

[0083] P1y - _min represents the minimum value of the main landing gear Y-axis negative direction;

[0084] P1z + _max represents the maximum value of the main landing gear Z-axis positive direction;

[0085] P1z + _min represents the minimum value of the main landing gear Z-axis positive direction;

[0086] P1z - _max represents the maximum value of the main landing gear Z-axis negative direction;

[0087] P1z - _min represents the minimum value of the main landing gear Z-axis negative direction;

[0088] P2x + _max represents the maximum value of the tail landing gear X-axis positive direction;

[0089] P2x + _min represents the minimum value of the tail landing gear X-axis positive direction;

[0090] P2x - _max represents the maximum value of the tail landing gear X-axis negative direction;

[0091] P2x- _min represents the minimum value of the tail landing gear in the X-axis negative direction;

[0092] P2y + _max represents the maximum value of the tail landing gear in the Y-axis positive direction;

[0093] P2y + _min represents the minimum value of the tail landing gear in the Y-axis positive direction;

[0094] P2y - _max represents the maximum value of the tail landing gear in the Y-axis negative direction;

[0095] P2y - _min represents the minimum value of the tail landing gear in the Y-axis negative direction;

[0096] P2z + _max represents the maximum value of the tail landing gear in the Z-axis positive direction;

[0097] P2z + _min represents the minimum value of the tail landing gear in the Z-axis positive direction;

[0098] P2z - _max represents the maximum value of the tail landing gear in the Z-axis negative direction;

[0099] P2z - _min represents the minimum value of the tail landing gear in the Z-axis negative direction;

[0100] (5) Set the trigonometric function load parameters, i.e. the loading function, by the computer controller, and load the load along the X, Y and Z axes in the same period (frequency), and pre-load the test data to the initial load value, and then load according to the sine period ( Figure 1 ) Drive the actuator by the driving source to implement excitation, and load reciprocatingly in the required loading direction to perform the loading test; collect the sea wave data according to the most severe sea conditions of the sea area where the ship sails to obtain the time required for one complete amplitude process of the ship's pitch or roll fluctuation, and the length of this time is used as the time within one loading cycle; and according to the statistical normal distribution of the most severe sea wave, the length of the time of the maximum probability of the continuous action is divided by the time required for one complete amplitude process of the pitch or roll fluctuation, which is the test frequency (loading times).

[0101] (6) Measure and record the change curve of the extension amount of the piston rod of the main landing gear and the tail landing gear with time. The test data of the displacement sensor is transmitted to the computer controller, and the test data is displayed and recorded in real time; when the test reaches the predetermined number of cycles, the test is ended;

[0102] (7) Each cycle is completed before the next cycle test, and all cycles are completed before the next test. When the working condition is converted, the high pressure chamber pressure and the low pressure chamber pressure of the main landing gear test piece and the tail landing gear test piece need to be adjusted again according to step (2);

[0103] (8) End test, compare the recorded test data with the theoretical data, if the test data is smaller than the theoretical data, verify that the landing gear has the limiting ability of high sea state; The theoretical data can be obtained by calculation and analysis, the calculation method: the application is aimed at the rear three-point landing gear structure, that is, the front part of the fuselage is provided with left and right main landing gears, and the rear part of the fuselage is provided with a tail landing gear; According to the length L of the main landing gear span and the angle a when the risk of overturning occurs, the limit length K of the length change of the main landing gear when the risk of lateral overturning occurs is calculated by using the geometric mathematical relationship K = (L / 2) tan a; According to the length S of the distance between the tail landing gear and the main landing gear along the X axis and the angle b when the risk of the nose lowest point touching the ground occurs (determined when the nose lowest point is displaced downward by M), the limit length N of the length change of the tail landing gear when the risk of the nose lowest point touching the ground occurs is calculated by using the geometric mathematical relationship N = Stanb; The calculated K and N are the theoretical data values.

[0104] The trigonometric function waveform takes the maximum load under the corresponding working condition as the peak and the minimum load as the trough; The ship pitch and roll fluctuation period is the loading period, and the ship pitch and roll fluctuation period can be obtained according to the sea state of the sea area where the ship sails to obtain the swing and fluctuation period and frequency of the ship;

[0105] A displacement sensor is installed between the main landing gear buffer strut outer cylinder 19 and the piston rod 20, and a displacement sensor is installed between the tail landing gear buffer strut outer cylinder 21 and the piston rod 22; The length change of the piston rod of the main landing gear and the tail landing gear is monitored by the sensor system test;

[0106] The function of increasing the main landing gear and tail landing gear loading interface is realized by installing test loading joints on the main landing gear and tail landing gear;

[0107] The limiting ability of the main landing gear and the tail landing gear is realized by the main landing gear telescopic limiter and the tail landing gear telescopic limiter;

[0108] The main landing arm clamp joint 3, the main landing buffer clamp joint 4, the main landing test bench 5 and the tail landing test bench 11 are used to simulate and replace the fuselage structure;

[0109] The test method can test the telescopic limiting ability of the main landing gear and the tail landing gear simultaneously or separately

[0110] Embodiment

[0111] Taking a single main landing gear test as an example:

[0112] a) Fix the main lifting rocker arm clamp joint 3 and the main lifting buffer clamp joint 4 on the test bench floor and adjust the spatial position. The X-axis distance between the installation center points of joints 3 and 4 is 834mm, the Y-axis distance is 0, and the Z-axis distance is 860mm. Install the main lifting and landing gear test piece on the joints and fix it in place.

[0113] b) Fix the main hoist Y-axis hydraulic actuator 6 and the main hoist Z-axis hydraulic actuator 7 onto the main hoisting load-bearing platform 8;

[0114] c) Release the high-pressure and low-pressure chambers of the main landing gear test piece;

[0115] d) Adjust the piston rod extension length of the main landing gear test piece to 260mm;

[0116] e) Install the main starter extension limiter;

[0117] f) Inflate the main landing gear test piece to a high-pressure chamber pressure of 4.8 MPa and a low-pressure chamber pressure of 1.5 MPa;

[0118] g) Install a displacement sensor between the outer cylinder 19 of the main landing gear buffer strut and the piston rod 20;

[0119] h) Determine the maximum load of the main landing gear in six directions based on the usage scenario of hangar mooring.

[0120] Load, minimum load: P1x+_max=0, P1x+_min=0, P1x-_max=0

[0121] P1x-_min=0, P1y+_max=8250N, P1y+_min=0N, P1y-_max=1300N,

[0122] P1y-_min=0, P1z+_max=73500N, P1z+_min=0, P1z-_max=0,

[0123] P1z-_min=0;

[0124] i) The trigonometric function load parameters are set by the computer controller and the test ends when the number of loading cycles reaches 25.

[0125] j) After this working condition is completed, repeat the test for the next working condition;

[0126] k) End the test, record 50mm of experimental data, and theoretically calculate the maximum displacement of the main starter.

[0127] K = 15mm < 50mm. The test results show that the main landing gear's limiting capability is insufficient and cannot meet the design requirements.

[0128] The above merely describes specific embodiments of the present application, and the detailed description of the present application is not exhaustive of the conventional technology. However, the protection scope of the present application is not limited to this, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered by the protection scope of the present application. The protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A high sea state landing gear limit performance simulation device, characterized by: The device comprises a main landing gear test piece, a main landing limiter, a main landing rocker arm clamp joint, a main landing buffer clamp joint, a main landing test bench, a main landing loading assembly, a tail landing gear test piece, a tail landing limiter, a tail landing test bench, and a tail landing loading assembly. The main landing gear test piece is completely identical to the real main landing gear, the rocker arm of the main landing gear test piece is installed on the main landing test bench through the main landing rocker arm clamp joint, the buffer of the main landing gear test piece is installed on the main landing test bench through the main landing buffer clamp joint, the main landing limiter is installed on the buffer of the main landing gear test piece to limit the stroke of the buffer, the axle of the rocker arm of the main landing gear test piece is provided with a main landing loading joint, and the main landing loading assembly loads the main landing gear test piece through the main landing loading joint. The tail landing gear test piece is completely identical to the real tail landing gear, the buffer of the tail landing gear test piece is installed on the tail landing test bench, the tail landing limiter is installed on the buffer of the tail landing gear test piece to limit the stroke of the buffer, the axles of the tail landing gear test piece are provided with tail landing loading joints, and the tail landing loading assembly loads the tail landing gear test piece through the tail landing loading joints. The main landing and tail landing loading assemblies load the main landing and tail landing gear test pieces respectively to simulate the loading condition of the helicopter when parked on the ship, so as to test the limiting performance of the main landing limiter and the tail landing limiter.

2. The apparatus of claim 1, wherein: The main landing loading joint comprises one or more X, Y and Z direction loading joints, and the main landing loading assembly comprises one or more X, Y and Z direction actuating cylinders fixed on the main landing actuating force platform.

3. The apparatus of claim 1, wherein: The tail landing loading joint comprises two Z direction loading joints arranged on the left and right axles, and the tail landing loading assembly comprises two tail landing Z direction actuating cylinders for loading the two Z direction loading joints on the left and right axles.

4. The apparatus of claim 1, wherein: The device further comprises a controller, which controls the main landing loading assembly and the tail landing loading assembly to test the main landing gear test piece and the tail landing gear test piece with a trigonometric function wave load.

5. The apparatus of claim 1, wherein: One end of the main landing limiter is fixed on the buffer outer cylinder of the main landing gear test piece, and the other end is fixed on the piston rod of the main landing gear test piece, and the maximum displacement of the piston rod relative to the buffer outer cylinder is limited by the elastic deformation of the main landing limiter. The tail landing limiter has a structure similar to that of the main landing limiter.

6. A method for simulating the performance of a high sea state landing gear limit, said method being carried out by means of the device according to any one of claims 1-5, characterized in that: The method comprises the following steps: Step one: install the main landing gear test piece and the tail landing gear test piece on the main landing test bench and the tail landing test bench respectively; Step two: install the main landing limiter and the tail landing limiter; Step three: install displacement sensors between the main landing gear buffer outer cylinder and the piston rod and between the tail landing gear buffer outer cylinder and the piston rod; Step four: select a test scenario, determine the maximum and minimum loads of the main landing gear in the X, Y and Z directions under tension and compression, and determine the maximum and minimum loads of the tail landing gear in the Z direction under tension and compression; Step five: determine the loading frequency. Step six: generating a trigonometric function waveform according to the load extreme value determined in step four and the loading frequency determined in step five, and controlling the main landing gear test piece and the tail landing gear test piece to be loaded by the main loading assembly and the tail loading assembly according to the trigonometric function waveform; Step seven: collecting displacement sensor data installed on the main landing gear and the tail landing gear, and comparing the displacement sensor data with theoretical data, if greater than the theoretical data, it is determined that the corresponding limiter has insufficient limiting performance, otherwise it is determined that the corresponding limiter has good limiting performance.

7. The method according to claim 6, characterized in that: In step two, the process of installing the main or tail limiter is as follows: Empty the fluid in the high-pressure cavity and the low-pressure cavity of the main or tail landing gear test piece; Adjust the piston rod extension length of the main or tail landing gear test piece buffer, so that the piston rod extension length is equal to the piston rod extension length when the helicopter is parked on the ship; Install the main or tail limiter; Fill the fluid in the high-pressure cavity and the low-pressure cavity of the main or tail landing gear test piece so that the pressure in the high-pressure cavity and the low-pressure cavity matches the piston rod extension length.

8. The method of claim 6, wherein: In step four, the test scenarios include: hangar mooring, deck mooring, transfer.

9. The method of claim 6, wherein: In step five, the loading frequency is determined by the following process: according to the most severe sea conditions of the sea area where the ship sails, the sea wave data is collected to obtain the time required for the ship to pitch or roll one complete amplitude, and this time length is used as the time in a loading cycle; and according to the normal distribution of the maximum probability of the severe sea wave, the time length of the continuous action is calculated, and the time length is divided by the time required for the ship to pitch or roll one complete amplitude, as the test frequency.

10. The method of claim 6, wherein: In step seven, the main landing gear theoretical data is calculated by the following process: According to the length L of the main landing gear and the angle a when the overturning risk occurs, the length change limit length K of the main landing gear is calculated; the formula is as follows: K=(L / 2)tan(a); a is the angle when the overturning risk occurs; The tail landing gear theoretical data is calculated by the following process: According to the length S of the tail landing gear and the lowest point of the nose, the angle b when the lowest point of the nose touches the ground, and the installation position of the main landing gear, the limit length N is calculated; the formula is as follows: N=Stan(b); B is the angle when the lowest point of the nose touches the ground.

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