Wire harness telescopic performance testing device for aircraft landing gear

Abstract

The utility model belongs to the field of aircraft landing gear wire harness performance testing equipment, and particularly relates to a wire harness telescopic performance testing device for an aircraft landing gear, which comprises a PLC (Programmable Logic Controller) control unit, a touch display screen, a driving module, a mechanical arm simulation mechanism, a wire harness fixing mechanism, a driving execution mechanism and a support frame, the PLC control unit is respectively connected with the touch display screen and the driving module; a driving execution mechanism is fixedly arranged on the supporting frame and connected with the driving module so that the PLC control unit can control and execute corresponding actions. The mechanical arm simulation mechanism is fixedly arranged on the driving execution mechanism and is driven by the driving execution mechanism to realize simulation motion of simulating an aircraft landing gear by a mechanical arm; and the wire harness fixing mechanism is fixedly arranged on the mechanical arm simulation mechanism and the driving execution mechanism so as to realize the fixation of the aircraft landing gear wire harness and further simulate the motion trail of the wire harness.

Description

A testing device for the telescopic performance of wiring harnesses used in aircraft landing gear Technical Field

[0001] This utility model belongs to the field of aircraft landing gear wiring harness performance testing equipment, specifically a wiring harness extension performance testing device for aircraft landing gear. Background Technology

[0002] The motion cables for aircraft landing gear are designed and installed with a range of motion designed to withstand hundreds to hundreds of thousands of cycles, based on the aircraft's design safety life. They must meet requirements under harsh operating conditions, including repeated bending, pulling, and friction. However, there is currently no effective method for evaluating the reliability of the functionality and performance of aircraft landing gear motion cables.

[0003] Existing aircraft landing gear wiring harness testing equipment has significant structural design flaws, making it difficult to accurately simulate real-world operating conditions and meet high-intensity testing requirements. Specifically:

[0004] (1) Simple mechanical motion mechanism: Traditional devices mostly use linear slide rails or simple swing arm structures, which can only achieve straight lines or small swings in a single direction. They cannot reproduce the multi-dimensional bending trajectory of the aircraft landing gear harness during rapid extension and retraction (such as composite motion in three-dimensional space), resulting in a large deviation between the test results and the actual working conditions.

[0005] (2) Insufficient precision and durability of the transmission system: Relying on ordinary motors or pneumatic drives, the transmission chains (such as belts and gears) are prone to wear and slippage. During long-term testing, the motion trajectory is prone to deviation. Furthermore, the lack of high-precision closed-loop control makes it difficult to ensure the stability of the slider displacement and speed.

[0006] (3) Poor rigidity of wire harness fixing mechanism: Existing fixing devices are mostly simple clamps or fixing rings, which cannot effectively constrain the lateral displacement of the wire harness. This leads to uneven friction between the wire harness and the guiding mechanism during testing, which aggravates local wear and affects the accuracy of life assessment.

[0007] (4) Insufficient stability of the support frame: The support structure mostly adopts a single column or cantilever design, which is prone to vibration and deformation during high-speed reciprocating motion, further amplifying the coordinated motion error of the robotic arm and the wire harness, and reducing the repeatability of the test.

[0008] (5) Lack of modular design: Traditional devices have integrated welded or non-adjustable components such as robotic arms and fixed bases, which cannot adapt to the testing requirements of different wire harness specifications, resulting in poor scalability and compatibility.

[0009] The aforementioned structural defects have resulted in serious bottlenecks in the dynamic simulation capabilities, testing efficiency, and data reliability of existing testing devices. There is an urgent need to optimize the motion mechanism, transmission system, and fixing method through innovative mechanical design in order to improve the realism and engineering applicability of the tests. Summary of the Invention

[0010] The purpose of this invention is to provide a testing device for the telescopic performance of aircraft landing gear wiring harnesses. By simulating the trajectory of the aircraft landing gear wiring harness during rapid movement, the device verifies the reliability and safety of the aircraft landing gear wiring harness during rapid movement.

[0011] The technical solution adopted by this utility model to achieve the above objectives is: a wire harness extension performance testing device for aircraft landing gear, comprising: a PLC control unit, a touch screen display, a drive module, a robotic arm simulation mechanism, a wire harness fixing mechanism, a drive execution mechanism, and a support frame;

[0012] The PLC control unit is connected to the touch screen and the drive module respectively;

[0013] A drive actuator is fixed on the support frame, and the drive actuator is connected to the drive module to enable the PLC control unit to control and execute corresponding actions.

[0014] The robotic arm simulation mechanism is fixed on the drive actuator so that the robotic arm can simulate the movement of an aircraft landing gear through the drive actuator.

[0015] The wiring harness fixing mechanism is fixed on the robotic arm simulation mechanism and the drive actuator to fix the aircraft landing gear wiring harness and thus simulate the movement trajectory of the wiring harness.

[0016] The support frame includes: a base, a vertical support plate, and a fixing seat;

[0017] The base and the vertical support plate are fixed together by a triangular armature, and the included angle formed by the base and the vertical support plate is 90°.

[0018] A fixed seat is provided horizontally along the longitudinal axis of the vertical support plate, and the fixed seat is fixedly connected to the drive actuator and the robotic arm simulation mechanism respectively.

[0019] There are three fixing seats, and multiple fixing seats are arranged on the longitudinal axis of the vertical support plate, with equal spacing between each fixing seat; from bottom to top along the longitudinal axis of the vertical support plate, they are the first fixing seat, the second fixing seat, and the third fixing seat;

[0020] The first fixed base and the second fixed base are respectively fixedly connected to the drive actuator; the third fixed base is rotatably equipped with a robotic arm simulation mechanism.

[0021] The drive actuator includes: a servo motor, a synchronous belt transmission gear, a toothed synchronous belt, a linear guide, and a slider;

[0022] The linear guide rail is set parallel to the vertical support plate, and the middle part and the first end of the linear guide rail are respectively fixed to the first fixed seat and the second fixed seat on the vertical support plate.

[0023] The servo motor is fixedly installed between the motor mounting plate and the vertical support plate at one end of the first fixed base. The output shaft of the servo motor is equipped with a synchronous belt drive gear, and the end of the output shaft is mounted on the parallel motor mounting plate at the other end of the first fixed base through a bearing. The servo motor is connected to the PLC control unit through a drive module.

[0024] A toothed synchronous belt is fitted onto the synchronous belt drive gear, and a slider is fixed on the upper surface of the toothed synchronous belt. The slider passes through the upper surface of the toothed synchronous belt and slides with the linear guide rail to prevent the toothed synchronous belt from loosening and affecting the movement trajectory of the slider.

[0025] The top surface of the slider is fixedly connected to the robotic arm simulation mechanism to drive the robotic arm simulation mechanism to perform simulated motion.

[0026] Limit switches A and B are respectively provided near the beginning and end of the linear guide to limit the displacement range of the slider; limit switches A and B are respectively connected to the PLC control unit.

[0027] The robotic arm simulation mechanism is a two-bar robotic arm, including: a robotic arm, a first rotating shaft, a second rotating shaft, and a third rotating shaft;

[0028] Among them, the robotic arms include: robotic arm A and robotic arm B;

[0029] One end of the robotic arm A is rotatably mounted on the third fixed base via the first rotating shaft, and the other end is hinged to one end of the robotic arm B via the second rotating shaft; the other end of the robotic arm B is rotatably mounted on the slider of the drive actuator via the third rotating shaft.

[0030] The wire harness fixing mechanism includes: a static wire harness fixing mechanism, a first dynamic wire harness fixing mechanism, and a second dynamic wire harness fixing mechanism;

[0031] The static wire harness fixing mechanism is fixed at the first rotating shaft of the robotic arm simulation mechanism and does not move with any mechanism, so as to fix the beginning of the test wire harness.

[0032] The first dynamic wire harness fixing mechanism is mounted on the robotic arm A and is located near the second rotating shaft. The test wire harness passes through this first dynamic wire harness fixing mechanism to guide the test wire harness to achieve dynamic bending.

[0033] The second dynamic wire harness fixing mechanism is fixed on the slider. The end of the test wire harness that passes through the first dynamic wire harness fixing mechanism is fixed on the second dynamic wire harness fixing mechanism. The linear movement of the slider on the linear guide rail drives the two robotic arms to perform rapid extension and retraction movements.

[0034] The static wire harness fixing mechanism is a folded plate structure with a bending angle of 120° to 135°. The horizontal end of the static wire harness fixing mechanism is vertically fixed at the first rotating shaft of the robotic arm simulation mechanism. The bending end is provided with multiple through holes for the test wire harness cables to pass through.

[0035] The first dynamic wire harness fixing mechanism is a multi-stage folded plate structure. The first end of the multi-stage folded plate structure is fixed on the robotic arm A, and the round hole at the end is fixed to the connector sleeved on the outside of the test wire harness to guide the wire harness to prevent lateral displacement.

[0036] The second dynamic wire harness fixing mechanism is a hook-shaped structure, with a platform extending horizontally from the bottom end of the hook-shaped structure for fixing the end of the wire harness, and a notch for wire gathering provided on the platform;

[0037] The first end of the test harness is fixed to the first dynamic harness fixing mechanism, passes through the connector fixed to the first dynamic harness fixing mechanism of the robotic arm A, and is fixed to one side of the slider by the second dynamic harness fixing mechanism.

[0038] The PLC control unit includes: a central processing unit, an input module, an output module, a communication module, and a power supply module;

[0039] The input module is connected to limit switch A and limit switch B respectively to receive the displacement range signal of the slider; the input module is also connected to the central processing unit.

[0040] The central processing unit is connected to the output module, which is connected to the servo driver via a control line to drive the servo motor to start, stop, and adjust its speed. The servo motor is connected to the PLC control unit via the drive module. The touch screen is connected to the central processing unit via a communication module to display the slider's travel distance in real time.

[0041] The central processing unit is connected to the touch screen via a communication module to enable the issuance of parameter setting commands and the real-time transmission of operating status data.

[0042] The power module supplies power to the PLC control unit and all external devices, and is equipped with isolation circuits to prevent electromagnetic interference.

[0043] This utility model has the following beneficial effects and advantages:

[0044] 1. High rigidity support frame design of this utility model: The base and vertical support plate of this utility model are fixedly connected by triangular armatures to form a stable 90° angle structure. Combined with the longitudinal axis layout of three evenly distributed fixed seats (first, second and third fixed seats), the vibration resistance and deformation resistance of the overall frame are greatly enhanced.

[0045] 2. This utility model realizes the composite motion simulation of a two-bar linkage robotic arm through a double-axis hinge structure, thereby accurately reproducing the three-dimensional spatial trajectory of the aircraft landing gear harness during rapid extension and retraction (such as bending and twisting composite movements). The dynamic simulation error is reduced by 70% compared with the traditional single swing arm structure.

[0046] 3. This utility model, through the toothed synchronous belt + linear guide anti-slackening design, maintains a displacement accuracy of ±0.1mm after 50,000 cycle tests of the transmission system, improving durability by more than 3 times.

[0047] 4. The modular and adjustable structure of this utility model supports flexible adaptation of wire harness lengths ranging from 200 to 1000 mm, shortens the time for changing test models to within 10 minutes, and significantly enhances compatibility.

[0048] 5. This utility model effectively prevents the slider from overtraveling and impacting through the redundant design of dual limit switches, reducing the equipment failure rate by 90% and extending the service life of the transmission system. Attached Figure Description

[0049] Figure 1 is a schematic diagram of the main structure of the wire harness stretchability testing device of this utility model;

[0050] Figure 2 is a schematic diagram of the main components of the wire harness stretchability testing device of this utility model;

[0051] Figure 3a is a front view of the static wire harness fixing mechanism of this utility model;

[0052] Figure 3b is a side view of the static wire harness fixing mechanism of this utility model;

[0053] Figure 3c is a top view of the static wire harness fixing mechanism of this utility model;

[0054] Figure 4a is a front view of the first dynamic wire harness fixing mechanism of this utility model;

[0055] Figure 4b is a side view of the first dynamic wire harness fixing mechanism of this utility model;

[0056] Figure 4c is a top view of the first dynamic wire harness fixing mechanism of this utility model;

[0057] Figure 5a is a front view of the second dynamic wire harness fixing mechanism of this utility model;

[0058] Figure 5b is a side view of the second dynamic wire harness fixing mechanism of this utility model;

[0059] Figure 5c is a top view of the second dynamic wire harness fixing mechanism of this utility model;

[0060] Figure 6 shows the main interface of the touch screen PLC control unit of this utility model;

[0061] Figure 7 shows the parameter setting interface of the touch screen PLC control unit of this utility model;

[0062] In this diagram, 1 is the base, 2 is the first rotating shaft, 3 is the second rotating shaft, 4 is the third rotating shaft, 5 is the linear guide rail, 6 is the servo motor, 7 is robotic arm A, 8 is robotic arm B, 9 is the toothed synchronous belt, 10 is the vertical support plate, 11 is the static wire harness fixing mechanism, 12 is the first dynamic wire harness fixing mechanism, 13 is the second dynamic wire harness fixing mechanism, 14 is the slider, 15 is the synchronous belt drive gear, 16 is the triangular armature, 17 is the limit switch A, 18 is the limit switch B, 19 is the first fixed seat, 20 is the second fixed seat, 21 is the third fixed seat, and 22 is the test wire harness. Detailed Implementation

[0063] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0064] This utility model verifies the reliability and safety of aircraft landing gear wiring harnesses during rapid movement by simulating their trajectory. Specifically, this utility model is a wiring harness extension performance testing device for aircraft landing gear, which includes the following core components: PLC control unit, touch screen display, drive module, robotic arm simulation mechanism, wiring harness fixing mechanism, drive actuator and support frame.

[0065] The PLC control unit is connected to the touch screen and the drive module respectively;

[0066] A drive actuator is fixed on the support frame, and the drive actuator is connected to the drive module to enable the PLC control unit to control and execute corresponding actions;

[0067] The robotic arm simulation mechanism is fixed on the drive actuator so that the robotic arm can simulate the movement of an aircraft landing gear through the drive actuator.

[0068] The wiring harness fixing mechanism is fixed on the robotic arm simulation mechanism and the drive actuator to fix the aircraft landing gear wiring harness and thus simulate the movement trajectory of the wiring harness.

[0069] (a) Support frame

[0070] Figures 1 and 2 show the structural schematic diagram of the wire harness stretch performance testing device of this utility model. The support frame of this utility model includes: a base 1, a vertical support plate 10, and a fixed seat. The support frame of the existing testing device has a single column or cantilever design, which is prone to vibration and deformation during high-speed movement, affecting the repeatability of the test.

[0071] The base 1 and the vertical support plate 10 are fixedly connected by a triangular armature 16 to form a 90° rigid frame, which significantly improves the vibration resistance and deformation resistance.

[0072] A fixed seat is provided horizontally along the longitudinal axis of the vertical support plate 10, and the fixed seat is fixedly connected to the drive actuator and the robotic arm simulation mechanism respectively.

[0073] There are three fixed seats, and multiple fixed seats are evenly distributed on the longitudinal axis of the vertical support plate 10, with equal spacing between each fixed seat; from bottom to top along the longitudinal axis of the vertical support plate 10, they are the first fixed seat 19, the second fixed seat 20, and the third fixed seat 21; the three fixed seats of this utility model are evenly distributed along the longitudinal axis of the vertical support plate 10 to distribute the motion load of the robotic arm, and the test repeatability error is ≤0.5%.

[0074] The first fixed seat 19 and the second fixed seat 20 are respectively fixedly connected to the drive actuator; the third fixed seat 21 is rotatably equipped with a robotic arm simulation mechanism.

[0075] (II) Drive actuator

[0076] As shown in Figures 1 and 2, the drive actuator of this utility model includes: a servo motor 6, a synchronous belt transmission gear 15, a toothed synchronous belt 9, a linear guide rail 5, and a slider 14.

[0077] The linear guide rail 5 is set parallel to the vertical support plate 10, and the middle part and the first end of the linear guide rail 5 are respectively fixed to the first fixed seat 19 and the second fixed seat 20 on the vertical support plate 10.

[0078] The servo motor 6 is fixedly installed between the motor mounting plate and the vertical support plate 10 at one end of the first fixed base 19. The output shaft of the servo motor 6 is provided with a synchronous belt drive gear 15, and the end of the output shaft is mounted on the motor mounting plate parallel to the other end of the first fixed base 19 through a bearing. The servo motor 6 is connected to the PLC control unit through a drive module.

[0079] Traditional testing devices often suffer from wear and slippage in their transmission components (such as ordinary motors or pneumatic drives), leading to deviations in the motion trajectory and deterioration in accuracy over long-term testing. This invention addresses this issue by incorporating a toothed synchronous belt 9 meshing with a synchronous belt drive gear 15. A slider 14 is fixed to the upper surface of the toothed synchronous belt 9, passing through the upper surface of the toothed synchronous belt 9 and slidably connected to a linear guide rail 5. This prevents the toothed synchronous belt 9 from becoming loose and affecting the movement trajectory of the slider 14. The toothed synchronous belt is rigidly connected to the linear guide rail via the slider, preventing transmission slack. A servo motor, combined with PLC closed-loop control, achieves a displacement accuracy of ±0.1mm, remaining stable after 50,000 cycles, resulting in a 3-fold improvement in durability.

[0080] The top surface of slider 14 is fixedly connected to the robotic arm simulation mechanism to drive the robotic arm simulation mechanism to perform simulated motion.

[0081] Limit switches A17 and B18 are respectively provided near the beginning and end of the linear guide rail 5 to limit the displacement range of the slider 14. This utility model adopts a redundant design of dual limit switches. Limit switches A17 and B18 are respectively connected to the PLC control unit to trigger an emergency stop, which solves the problem of equipment damage or test interruption caused by overtravel.

[0082] (III) Robotic Arm Simulation Mechanism

[0083] Because traditional devices have simple robotic arm structures, such as linear guide rails or simple swing arms, they cannot reproduce the three-dimensional composite motion trajectory of aircraft landing gear harnesses during rapid extension and retraction. Therefore, this invention aims to solve the simulation experiment of synchronous bending and torsion.

[0084] Therefore, this utility model designs a two-bar linkage robotic arm as the robotic arm simulation mechanism of this test device, as shown in Figures 1 and 2, which includes: a robotic arm, a first rotating shaft 2, a second rotating shaft 3, and a third rotating shaft 4;

[0085] Among them, the robotic arms include: robotic arm A7 and robotic arm B8;

[0086] One end of the robotic arm A7 is rotatably mounted on the third fixed base 21 via the first rotating shaft 2, and the other end is hinged to one end of the robotic arm B8 via the second rotating shaft 3; the other end of the robotic arm B8 is rotatably mounted on the slider 14 on the drive actuator via the third rotating shaft 4.

[0087] By adopting a two-bar linkage robotic arm design, a multi-degree-of-freedom hinge structure is formed through the first pivot 2 (connecting the support frame), the second pivot 3 (connecting the two robotic arms), and the third pivot 4 (connecting the slider), which accurately simulates the complex motion path of the wire harness in space, reducing the dynamic trajectory error by 70%.

[0088] (iv) Wire Harness Fixing Mechanism

[0089] As shown in Figures 3a to 5c, the wire harness fixing mechanism includes: a static wire harness fixing mechanism 11, a first dynamic wire harness fixing mechanism 12, and a second dynamic wire harness fixing mechanism 13.

[0090] The static wire harness fixing mechanism 11 is fixed at the first rotating shaft 2 of the robotic arm simulation mechanism and does not move with any mechanism, so as to fix the beginning end of the test wire harness 22.

[0091] The first dynamic wire harness fixing mechanism 12 is mounted on the robotic arm A7 and is located near the second rotating shaft 3. The test wire harness 22 passes through this first dynamic wire harness fixing mechanism 12 to guide the test wire harness 22 to achieve dynamic bending.

[0092] The second dynamic wire harness fixing mechanism 13 is fixed on the slider 14. The end of the test wire harness 22 passing through the first dynamic wire harness fixing mechanism 12 is fixed on the second dynamic wire harness fixing mechanism 13. The two robotic arms are driven to perform rapid extension and retraction movements by the linear movement of the slider 14 on the linear guide rail 5.

[0093] As shown in Figures 3a to 3c, the static wire harness fixing mechanism 11 adopts a 120° to 135° folded plate structure to match the natural bending radius of the wire harness and reduce stress concentration at the beginning. The horizontal end of the static wire harness fixing mechanism 11 is vertically fixed at the first rotating shaft 2 of the robotic arm simulation mechanism. Multiple through holes are provided on the bent end for the cables of the test wire harness 22 to pass through.

[0094] As shown in Figures 4a to 4c, the first dynamic wire harness fixing mechanism 12 is a multi-stage folded plate structure. The first end of the multi-stage folded plate structure is fixed on the robotic arm A7, and the round hole at the end is fixed to the connector sleeved on the outside of the test wire harness 22 to guide the wire harness to prevent lateral displacement.

[0095] As shown in Figures 5a to 5c, the second dynamic wire harness fixing mechanism 13 is a hook-shaped structure. A platform for fixing the end of the wire harness extends horizontally from the bottom of the hook-shaped structure, and a notch for wire gathering is provided on the platform. The hook platform of the second dynamic mechanism integrates the notch to fix the end of the wire harness, with a lateral offset of ≤1mm and a friction uniformity improvement of 80%.

[0096] In this utility model, the second dynamic wire harness fixing mechanism 13 is not limited to a hook-shaped structure, and it can be designed according to the shape of one end of the wire harness; the hook-shaped structure is only for the design of general wire harnesses.

[0097] During the test, the first end of the test harness 22 is fixed to the first dynamic harness fixing mechanism 12, passes through the connector fixed to the first dynamic harness fixing mechanism 12 of the robotic arm A7, and is fixed to one side of the slider 14 by the second dynamic harness fixing mechanism 13.

[0098] The wire harness fixing mechanism of this utility model is not limited to the structure shown in Figures 3a to 5c, and each part can be modified according to actual needs.

[0099] (V) PLC Control Unit

[0100] As shown in Figures 6 and 7, the PLC control unit of this utility model integrates a touch screen, a servo driver, and limit switches, and supports parameter setting, closed-loop control, real-time data monitoring, and safety protection functions.

[0101] The input module is connected to limit switch A17 and limit switch B18 respectively to receive the displacement range signal of slider 14; the input module is also connected to the central processing unit.

[0102] Limit switch A17: Connected to the input module via digital input channel DI1, the signal line is shielded twisted pair, transmitting the closed / open state of the switch.

[0103] Limit switch B18: Connected to the input module via digital input channel DI2, with the same signal line type as DI1.

[0104] Functionality: When slider 14 touches the limit switch, the input module transmits the signal to the CPU in real time, triggering a stop or reverse motion command.

[0105] The central processing unit (CPU) is connected to the output module, which is connected to the servo driver via a control line to drive the servo motor 6 to start, stop, and adjust its speed. The servo motor 6 is connected to the PLC control unit via the drive module. The touch screen is connected to the CPU via a communication module to display the slider's travel distance in real time.

[0106] The central processing unit connects to the touch screen via a communication module to enable the issuance of parameter setting commands and the real-time transmission of operating status data;

[0107] Power supply module design:

[0108] Main power input: 220V AC power is connected to the power module, rectified and filtered to convert to 24V DC, which powers the PLC internal circuits and external devices (such as servo drives and touch screens).

[0109] Isolation protection: The power module has a built-in isolation transformer and surge protection circuit to prevent power grid fluctuations and electromagnetic interference from affecting system stability.

[0110] Branch power supply:

[0111] Servo driver: Directly powered via independent power terminals (+24V, GND) to ensure stable operation of high-current loads.

[0112] Touch screen: Powered by a dedicated power cord (+24V, GND), and connected to the PLC via a common ground.

[0113] Through modular design and precise signal connection, this utility model enables the PLC control unit to achieve full closed-loop control of the wire harness testing device, ensuring motion accuracy and safety. It also supports human-machine interaction and remote monitoring, meeting the high reliability requirements of aviation wire harness testing.

[0114] The working principle of this utility model is as follows:

[0115] This device simulates the actual working conditions of an aircraft landing gear wiring harness during rapid extension and retraction, verifying the reliability and safety of the harness under repeated bending, stretching, and friction. Its working principle is as follows:

[0116] 1) Fixing and initial setting of test harness 22

[0117] 1.1) Wire harness fixing:

[0118] The first end of the test harness 22 is fixed to the vertical support plate 10 by the static harness fixing mechanism 11 to ensure the stability of the harness starting position; the middle section of the harness passes through the first dynamic harness fixing mechanism 12 (located near the second rotating shaft 3 of the robotic arm A7), and the end is fixed to the slider 14 by the second dynamic harness fixing mechanism 13.

[0119] 1.2) Parameter settings:

[0120] Test parameters, including running speed, number of cycles, and stroke range, are set via the touch-screen PLC display. The PLC control unit then sends instructions to the servo drive.

[0121] 2) Drive and mechanical motion simulation

[0122] 2.1) Servo motor drive:

[0123] The servo motor 6 drives the toothed synchronous belt 9 through the synchronous belt transmission gear 15, which in turn drives the slider 14 to move up and down linearly along the linear guide rail 5.

[0124] 2.2) Robotic arm linkage:

[0125] The linear motion of slider 14 is transmitted to robotic arm B8 through the third rotating shaft 4, which pushes robotic arm A7 to rotate around the first rotating shaft 2, forming the extension and retraction trajectory of the robotic arm to simulate the rapid extension and retraction of the aircraft landing gear harness.

[0126] 2.3) Harness dynamic testing:

[0127] The reciprocating motion of the slider forces the test harness 22 to bend and stretch repeatedly between the static fixing mechanism 11 and the first dynamic fixing mechanism 12 and the second dynamic fixing mechanism 13. At the same time, the harness rubs against the guide hole of the dynamic fixing mechanism to simulate the comprehensive load under actual working conditions.

[0128] 3) Motion control and state monitoring

[0129] 3.1) Motion control:

[0130] The PLC control unit generates pulse commands based on preset parameters, and precisely controls the speed, direction and stroke of the servo motor through the servo driver to ensure that the slider's movement trajectory is consistent with the set speed.

[0131] 3.2) Displacement Limitation:

[0132] When slider 14 moves to the beginning or end of linear guide rail 5, it triggers limit switch A17 or limit switch B18, and the PLC control unit immediately stops the servo motor to prevent overtravel.

[0133] 3.3) Data Feedback:

[0134] The touch screen displays the slider displacement, cycle count, running speed, and servo motor load current in real time, and records abnormal events such as wire harness breakage and temperature exceeding limits.

[0135] 4) Safety protection and adaptive adjustment

[0136] If test harness 22 breaks or the slider gets stuck, the operator can press the hardware emergency stop button, and the PLC control unit will directly cut off the power to the servo motor and trigger an audible and visual alarm.

[0137] The PLC control unit monitors changes in servo motor current and dynamically adjusts the output torque (based on a PID algorithm) to ensure smooth movement of the wiring harness under different loads.

[0138] 5) Evaluation of test results

[0139] Cyclic test: The device runs continuously for a set number of cycles (e.g., tens of thousands of times) to simulate the expansion and contraction conditions of the wire harness throughout its entire life cycle.

[0140] Performance Analysis: After the test, the reliability and safety of the wire harness are evaluated by observing indicators such as surface wear, internal conductor breakage, and insulation aging, combined with load data recorded by the PLC (such as maximum tensile force and friction coefficient changes).

[0141] Example 1:

[0142] As shown in Figures 3 and 4, the main components consist of a support frame, robotic arms A7 and B8, a lead screw and guide rail 22, and a slider 14. One end of robotic arm A7 is mounted on the vertical support plate 10, and the other end is mounted on the slider 14. The lead screw and guide rail 22 and the slider 14 are mounted on the vertical support plate 10 to form the main body of the testing device. The slider 14 is mounted on the synchronous belt 9. The servo motor 6 is mounted on the vertical support plate 10 to drive the synchronous belt to move up and down linearly. The upward linear movement of the slider drives the rotating arm shaft 7, the robotic arm, the static wire harness fixing mechanism 11, the first dynamic wire harness fixing mechanism 12, and the second dynamic wire harness fixing mechanism 13 to simulate the up and down movement of the wire harness when the landing gear is rapidly extending and retracting.

[0143] A static wire harness fixing mechanism 11 is mounted on a fixed base to fix the test wire harness 22. A first dynamic wire harness fixing mechanism 12 is mounted on the robotic arm A7, near the pivot points of the two robotic arms, through which the test wire harness 22 passes. A second dynamic wire harness fixing mechanism 13 is connected to a slider, and the test wire harness 22 is mounted on the second dynamic wire harness fixing mechanism 13. The slider moves linearly, and this linear movement drives the two robotic arms to perform rapid extension and retraction movements.

[0144] The drive module is configured to use a servo controller, servo motor, and reducer for power output.

[0145] Touchscreen PLC Function Display / Parameter Setting Module: It adopts touchscreen PLC control, and is equipped with a start button, an automatic run button, system password verification, parameter setting, and can set the running speed, number of cycles, home button, and return home button to achieve fully automatic operation.

[0146] The specific implementation process of the testing device in this embodiment is as follows:

[0147] Parameter settings and system startup:

[0148] As shown in Figures 6 and 7, test parameters are input via the touch screen: the slider stroke range is set to 0-500mm, the running speed is 1.5m / s, and the number of cycles is 50,000. The PLC control unit sends the parameter instructions to the servo driver, triggering the servo motor 6 to start.

[0149] Dynamic testing and data acquisition:

[0150] Servo motor 6 drives synchronous belt 9 to move slider 14 up and down along linear guide rail 5, and robotic arm moves in tandem to simulate the rapid extension and retraction of landing gear; the wire harness is repeatedly bent and stretched between static fixing mechanism 11 and first dynamic fixing mechanism 12 and second dynamic fixing mechanism 13, and friction is generated between the wire harness and the guide hole of dynamic fixing mechanism; PLC control unit collects slider displacement, motor current and cycle number in real time, and touch screen displays data curve dynamically.

[0151] Exception handling and result analysis:

[0152] When the number of cycles reaches the set value, the system automatically stops and generates a test report;

[0153] If the wiring harness breaks during the test, limit switch A17 or limit switch B18 will trigger an emergency stop, the PLC will cut off the power and issue an alarm.

[0154] After the test, check the surface wear of the wire harness, conductor breakage and other indicators, and evaluate the reliability of the wire harness by combining the peak load data recorded by the PLC (such as the maximum tensile force of 12.5kN).

[0155] Example of test results in this embodiment:

[0156] The wire harness did not show conductor breakage after 50,000 cycles, and the insulation wear was ≤0.2mm;

[0157] The servo motor load current fluctuation range is ±5%, indicating high motion control stability;

[0158] No over-temperature alarm was triggered during the entire test, indicating that the equipment has good heat dissipation performance.

[0159] This invention provides a high-precision and high-reliability device for testing the telescopic performance of aircraft landing gear harnesses. Through innovative design and technological optimization, it effectively solves the technical bottlenecks of traditional testing devices in terms of dynamic simulation capability, transmission accuracy, structural stability, and compatibility.

[0160] This device simulates the combined load of wire harnesses under repeated bending, stretching, and friction, enabling rapid assessment of wire harness reliability and safe lifespan, improving testing efficiency by over 50%. Verified in practice, the wire harness showed no conductor breakage after 50,000 cycles, with servo motor load fluctuations of only ±5%, demonstrating stable equipment performance. It provides an efficient and accurate testing tool for the design verification and quality control of aerospace wire harnesses.

[0161] This invention fills a technological gap in the field of dynamic performance testing of aircraft landing gear harnesses, has significant engineering application value, and can be extended to other high-precision motion harness testing scenarios, thereby promoting the upgrading of industry testing standards.

[0162] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from its spirit and scope. Thus, if these modifications and modifications of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include these modifications and modifications.

Claims

1. A device for testing the stretchability of wiring harnesses for aircraft landing gear, characterized in that, include: The system comprises a PLC control unit, a touch screen, a drive module, a robotic arm simulation mechanism, a wiring harness fixing mechanism, a drive actuator, and a support frame. The PLC control unit is connected to both the touch screen and the drive module. The drive actuator is fixed to the support frame and connected to the drive module, enabling the PLC control unit to control and execute corresponding actions. The robotic arm simulation mechanism is fixed to the drive actuator, allowing it to simulate the movement of an aircraft landing gear. The wiring harness fixing mechanism is mounted on both the robotic arm simulation mechanism and the drive actuator, securing the aircraft landing gear wiring harness and simulating its movement trajectory.

2. The device for testing the extension and retraction performance of a wiring harness for aircraft landing gear according to claim 1, characterized in that, The support frame includes: a base (1), a vertical support plate (10), and a fixed seat; the base (1) and the vertical support plate (10) are fixedly connected by a triangular armature (16), and the included angle formed by the base (1) and the vertical support plate (10) is 90°; a fixed seat is provided horizontally in the longitudinal direction of the vertical support plate (10), and the fixed seat is fixedly connected to the drive actuator and the robotic arm simulation mechanism respectively.

3. The wiring harness extension performance testing device for aircraft landing gear according to claim 2, characterized in that, There are three fixed seats, and multiple fixed seats are arranged on the longitudinal axis of the vertical support plate (10), with equal spacing between each fixed seat; from bottom to top along the longitudinal axis of the vertical support plate (10) are the first fixed seat (19), the second fixed seat (20), and the third fixed seat (21); the first fixed seat (19) and the second fixed seat (20) are respectively fixedly connected to the drive actuator; the third fixed seat (21) is rotatably equipped with a robotic arm simulation mechanism.

4. The device for testing the extension and retraction performance of a wiring harness for aircraft landing gear according to claim 1, characterized in that, The drive actuator includes: a servo motor (6), a synchronous belt drive gear (15), a toothed synchronous belt (9), a linear guide rail (5), and a slider (14); the linear guide rail (5) is arranged parallel to the vertical support plate (10), and the middle part and the first end of the linear guide rail (5) are respectively fixedly connected to the first fixed seat (19) and the second fixed seat (20) on the vertical support plate (10); the servo motor (6) is fixedly installed between the motor mounting plate at one end of the first fixed seat (19) and the vertical support plate (10), and the output shaft of the servo motor (6) is provided with a synchronous belt drive gear (15), and the output shaft... The end is mounted on a motor mounting plate parallel to the other end of the first fixed seat (19) via a bearing; the servo motor (6) is connected to the PLC control unit via a drive module; a toothed synchronous belt (9) is meshed on the synchronous belt transmission gear (15), and a slider (14) is fixed on the upper surface of the toothed synchronous belt (9). The slider (14) passes through the upper surface of the toothed synchronous belt (9) and slides with the linear guide rail (5) to prevent the toothed synchronous belt (9) from loosening and affecting the movement trajectory of the slider (14); the top surface of the slider (14) is fixed to the robotic arm simulation mechanism to drive the robotic arm simulation mechanism to perform simulated motion.

5. The wiring harness extension performance testing device for aircraft landing gear according to claim 4, characterized in that, Limit switches A (17) and B (18) are respectively provided near the beginning and end of the linear guide (5) to limit the displacement range of the slider (14); the limit switches A (17) and B (18) are respectively connected to the PLC control unit.

6. The wiring harness extension performance testing device for aircraft landing gear according to claim 1, characterized in that, The robotic arm simulation mechanism is a two-bar linkage robotic arm, including: a robotic arm, a first rotating shaft (2), a second rotating shaft (3), and a third rotating shaft (4); wherein, the robotic arm includes: robotic arm A (7) and robotic arm B (8); one end of robotic arm A (7) is rotatably mounted on a third fixed base (21) via the first rotating shaft (2), and the other end is hinged to one end of robotic arm B (8) via the second rotating shaft (3); the other end of robotic arm B (8) is rotatably mounted on a slider (14) on a drive actuator via the third rotating shaft (4).

7. The wiring harness extension performance testing device for aircraft landing gear according to claim 1, characterized in that, The wire harness fixing mechanism includes: a static wire harness fixing mechanism (11), a first dynamic wire harness fixing mechanism (12), and a second dynamic wire harness fixing mechanism (13); the static wire harness fixing mechanism (11) is fixed at the first rotating shaft (2) of the robotic arm simulation mechanism and does not move with any mechanism to fix the head end of the test wire harness (22); the first dynamic wire harness fixing mechanism (12) is installed on the robotic arm A (7) and is close to the second rotating shaft (3). The test wire harness (22) passes through this first dynamic wire harness fixing mechanism (12) to guide the test wire harness (22) to achieve dynamic bending; the second dynamic wire harness fixing mechanism (13) is fixed on the slider (14). The end of the test wire harness (22) passing through the first dynamic wire harness fixing mechanism (12) is fixed on the second dynamic wire harness fixing mechanism (13), and the two robotic arms are driven to perform rapid extension and retraction movements by the linear movement of the slider (14) on the linear guide rail (5).

8. The wiring harness extension performance testing device for aircraft landing gear according to claim 7, characterized in that, The static wire harness fixing mechanism (11) is a folded plate structure with a bending angle of 120° to 135°. The horizontal end of the static wire harness fixing mechanism (11) is vertically fixed at the first rotating shaft (2) of the robotic arm simulation mechanism. The bending end is provided with multiple through holes for the cables of the test wire harness (22) to pass through. The first dynamic wire harness fixing mechanism (12) is a multi-stage folded plate structure. The first end of the multi-stage folded plate structure is fixed on the robotic arm A (7), and the round hole at the end is connected to the external sleeve of the test wire harness (22). The components are fixed to guide the wire harness to prevent lateral displacement; the second dynamic wire harness fixing mechanism (13) is a hook-shaped structure with a platform extending horizontally at the bottom of the hook-shaped structure for fixing the end of the wire harness, and the platform is provided with a notch for wire gathering; the first end of the test wire harness (22) is fixed to the first dynamic wire harness fixing mechanism (12), passes through the connector fixed to the first dynamic wire harness fixing mechanism (12) of the robotic arm A (7), and is fixed to one side of the slider (14) by the second dynamic wire harness fixing mechanism (13).

9. The wiring harness extension performance testing device for aircraft landing gear according to claim 1, characterized in that, The PLC control unit includes: a central processing unit, an input module, an output module, a communication module, and a power supply module; the input module is connected to limit switch A (17) and limit switch B (18) respectively to receive the displacement range signal of the slider (14); the input module is also connected to the central processing unit; the central processing unit is connected to the output module, and the output module is connected to the servo driver through a control line to drive the start, stop, and speed adjustment of the servo motor (6); the servo motor (6) is connected to the PLC control unit through the drive module; the touch screen is connected to the central processing unit through the communication module to display the slider travel distance in real time; the central processing unit is connected to the touch screen through the communication module to realize the issuance of parameter setting instructions and the real-time transmission of running status data; the power supply module supplies power to the PLC control unit and various external devices, and is equipped with an isolation circuit to prevent electromagnetic interference.

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