A laser calibration device for thin-walled shell axial compression test
Patent Information
- Application Number
- CN202610636632.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-09
- Publication Date
- 2026-08-18
AI Technical Summary
1） 复合材料具有显著的各向异性特征，导致壳体在轴向压缩加载过程中应力分布复杂，易出现局部应力集中，对测试过程中的定位校准精度提出更高要求；
本发明提供的薄壁壳体轴压试验激光校准装置，将激光校准仪系统与机械执行系统深度集成，共享同一坐标系，消除了传统分离式设计的系统误差，实现了测量-控制-执行的闭环协同工作，能够实现轴向压缩试验过程中复合材料薄壁壳体的高精度定位与动态校准，本发明在夹紧机构的夹紧端面嵌入有压力传感器，压力传感器能够实时采集锁紧力信号，并将信号反馈至控制单元，能够在薄壁壳体的装夹时，避免应力集中，实现薄壁、异形壳体的无损定位固定，避免壳体因应力集中产生的试验误差。
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Figure CN122590764A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of axial compression testing technology, and in particular to a laser calibration device for axial compression testing of thin-walled shells. Background Technology
[0002] Thin-walled shells have critical application value in the aerospace field, and their axial compression performance directly affects the reliability and safety of related equipment. Therefore, extremely high requirements are placed on the accuracy and stability of their axial compression performance testing. Currently, the axial compression performance testing of thin-walled shells faces the following core technical challenges, which restrict the testing accuracy and engineering application effectiveness: (a) Testing challenges arising from material properties 1) Composite materials have significant anisotropic characteristics, which leads to complex stress distribution in the shell during axial compression loading and easy local stress concentration, which places higher demands on the positioning and calibration accuracy during the testing process; 2) Most thin-walled shells adopt a thin-walled structure design, which is extremely sensitive to the clamping method and clamping force. Improper clamping can easily lead to shell deformation and damage, which in turn affects the authenticity of the test data. 3) Composite materials have inherent creep characteristics and are prone to displacement drift during axial compression loading, which urgently requires real-time monitoring and dynamic calibration; 4) In practical engineering applications, thin-walled shells come in various specifications and have large diameter differences, which places high demands on the adaptability and changeover efficiency of the testing equipment.
[0003] (ii) Test accuracy requirements 1) The failure mechanism of thin-walled shells is complex. In the failure analysis process, it is necessary to achieve sub-millimeter or even sub-micron level positioning accuracy in order to accurately capture the failure location and morphology and provide a reliable basis for performance optimization. 2) During axial compression loading, the shell is prone to slight displacement and attitude shift, which requires real-time dynamic monitoring and timely calibration to avoid the cumulative deviation affecting the test results.
[0004] In view of this, we propose a laser calibration device for axial compression testing of thin-walled shells to solve the technical problems existing in the current process of testing the axial compression performance of thin-walled shells. Summary of the Invention
[0005] The purpose of this invention is to provide a laser calibration device for axial compression testing of thin-walled shells, so as to solve the problems existing in the prior art. It can achieve high-precision positioning and calibration of thin-walled shells of composite materials during axial compression testing, and can avoid stress concentration when the shell is clamped and fixed, thus achieving non-destructive clamping and locking of the shell.
[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a laser calibration device for axial compression testing of thin-walled shells, comprising a laser calibration system, a control unit, a servo motor, a lead screw adjustment mechanism, and a clamping mechanism. The laser calibration system and the clamping mechanism are integrated into one unit. The control unit is electrically connected to the laser calibration system, the servo motor, the lead screw adjustment mechanism, and the clamping mechanism to achieve closed-loop control. The laser calibration system and the clamping mechanism use the same reference coordinate system. The clamping mechanism is used for non-destructive positioning and locking of the thin-walled shell. A pressure sensor is embedded in the clamping end face of the clamping mechanism. The pressure sensor is used to collect the locking force signal in real time and feed the signal back to the control unit. The servo motor is used to drive the lead screw adjustment mechanism. The laser calibration system is used to monitor the displacement and positioning deviation of the thin-walled shell in real time, and works with the control unit, the servo motor, and the lead screw adjustment mechanism to complete dynamic calibration.
[0007] In one embodiment, the laser calibration system includes a laser emitter, a position detector, a laser tracker, and a multi-axis robot; the laser emitter and the position detector are located on both sides of the clamping mechanism and connected to the lead screw adjustment mechanism, which can drive the laser emitter and the position detector to move synchronously; the laser tracker and the multi-axis robot work together to establish a three-dimensional coordinate system and achieve sub-millimeter-level positioning.
[0008] In one embodiment, the laser emitter emits a visible red laser beam with a wavelength of 635 nm; the displacement measurement resolution of the position detector is 0.5 μm.
[0009] In one embodiment, the laser calibration system includes a support frame, with a lead screw adjustment mechanism connected to each end of the support frame, and the two lead screw adjustment mechanisms are driven by the same servo motor via a synchronous belt.
[0010] In one embodiment, the clamping mechanism includes a base, a V-block, a hinge plate, a first hinge bolt, a second hinge bolt, and a hinge socket. The base is disposed at the bottom of the support frame. Two V-blocks are fixed side by side on the base. The V-grooves of the V-blocks are used to place thin-walled shells. The hinge socket is fixed on the base and located on one side of the V-blocks. One end of the hinge plate has a pin hole, and the other end of the hinge plate has a side slot. One end of the first hinge bolt is connected to the pin hole through a pin, and the other end of the first hinge bolt is threaded to the base. One end of the second hinge bolt is connected to the hinge socket through a pin, and the other end of the second hinge bolt can be embedded in the side slot and threaded to a clamping nut, which presses down on the hinge plate.
[0011] The present invention achieves the following technical effects compared to the prior art: The laser calibration device for axial compression testing of thin-walled shells provided by this invention deeply integrates the laser calibration system with the mechanical execution system, sharing the same coordinate system. This eliminates the system errors of traditional separate designs and realizes closed-loop collaborative work of measurement-control-execution. It can achieve high-precision positioning and dynamic calibration of thin-walled composite shells during axial compression testing. This invention embeds a pressure sensor on the clamping end face of the clamping mechanism. The pressure sensor can collect the locking force signal in real time and feed the signal back to the control unit. This can avoid stress concentration when clamping the thin-walled shell, realize non-destructive positioning and fixing of thin-walled and irregularly shaped shells, and avoid test errors caused by stress concentration. Attached Figure Description
[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0013] Figure 1 This is a block diagram of the laser calibration instrument system in an embodiment of the present invention; Figure 2 This is a schematic diagram of the laser calibration device for thin-walled shell axial compression testing in an embodiment of the present invention; Figure 3 This is a schematic diagram of the clamping mechanism in an embodiment of the present invention; Figure 4 This is a schematic diagram of the clamping mechanism from another perspective in an embodiment of the present invention; Figure 5 This is a schematic diagram of the connection structure between the servo motor and the lead screw adjustment mechanism in an embodiment of the present invention; Figure 6 This is a schematic diagram of the hinge pressure plate in an embodiment of the present invention; Figure 7 This is a schematic diagram of the hinge socket in an embodiment of the present invention; Figure 8 This is a schematic diagram of the base of the clamping mechanism in an embodiment of the present invention.
[0014] In the diagram: 1-Laser calibrator system, 2-Servo motor, 3-Screw adjustment mechanism, 4-Clamping mechanism, 5-Thin-walled housing, 6-Laser emitter, 7-Position detector, 8-Support frame, 9-Base, 10-V-block, 11-Hinge plate, 12-First hinge bolt, 13-Second hinge bolt, 14-Hinge socket, 15-Pin hole, 16-Side slot, 17-Pin, 18-Pressure nut, 19-Screw, 20-Synchronous belt, 21-First fixing frame, 22-Second fixing frame, 23-First guide rod, 24-Second guide rod. Detailed Implementation
[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0016] The purpose of this invention is to provide a laser calibration device for axial compression testing of thin-walled shells, so as to solve the problems existing in the prior art. It can achieve high-precision positioning and calibration of thin-walled shells of composite materials during axial compression testing, and can avoid stress concentration when the shell is clamped and fixed, thus achieving non-destructive clamping and locking of the shell.
[0017] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0018] like Figures 1-8 As shown, this embodiment provides a laser calibration device for axial compression testing of thin-walled shells, including a laser calibration system 1, a control unit, a servo motor 2, a lead screw adjustment mechanism 3, and a clamping mechanism 4. The laser calibration system 1 and the clamping mechanism 4 are integrated. The control unit is electrically connected to the laser calibration system 1, the servo motor 2, the lead screw adjustment mechanism 3, and the clamping mechanism 4 respectively to achieve closed-loop control. The laser calibration system 1 and the clamping mechanism 4 adopt the same reference coordinate system. The clamping mechanism 4 is used for non-destructive positioning and locking of the thin-walled shell 5. A pressure sensor is embedded in the clamping end face of the clamping mechanism 4. The pressure sensor is used to collect the locking force signal in real time and feed the signal back to the control unit. The servo motor 2 is used to drive the lead screw adjustment mechanism 3 to operate. The laser calibration system 1 is used to monitor the displacement and positioning deviation of the thin-walled shell 5 in real time, and works with the control unit, the servo motor 2, and the lead screw adjustment mechanism 3 to complete dynamic calibration.
[0019] The laser calibration system 1 includes a laser emitter 6, a position detector 7, a laser tracker, and a multi-axis robot. The laser emitter 6 and the position detector 7 are located on both sides of the clamping mechanism 4 and are connected to the lead screw adjustment mechanism 3. The lead screw adjustment mechanism 3 can drive the laser emitter 6 and the position detector 7 to move synchronously. The laser tracker and the multi-axis robot work together to establish a three-dimensional coordinate system and achieve sub-millimeter-level positioning.
[0020] Laser emitter 6 emits a visible red laser beam with a wavelength of 635nm; position detector 7 has a displacement measurement resolution of 0.5μm.
[0021] The laser calibration system includes a support frame 8, with a lead screw adjustment mechanism 3 connected to each end of the support frame 8. The two lead screw adjustment mechanisms 3 are driven by the same servo motor 2 via a synchronous belt. Specifically, a drive pulley is fixed to the output shaft of the servo motor 2, and driven pulleys are fixed to the lead screws 19 of each of the two lead screw adjustment mechanisms 3. The drive pulley is connected to the two driven pulleys via a synchronous belt 20. The laser emitter 6 is fixed to a first fixed frame 21, and the position detector 7 is fixed to a second fixed frame 22. The first fixed frame 21 is threaded to one of the lead screws 19 and guided by a first guide rod 23. The second fixed frame 22 is threaded to the other lead screw 19 and guided by a second guide rod 24. Driven by the servo motor 2, the laser emitter 6 and the position detector 7 can move synchronously along the lead screws 19.
[0022] The clamping mechanism 4 includes a base 9, a V-block 10, a hinge plate 11, a first hinge bolt 12, a second hinge bolt 13, and a hinge socket 14. The base 9 is located at the bottom of the support frame 8. Two V-blocks 10 are fixed side by side on the base 9. The V-groove of the V-block 10 is used to place the thin-walled shell 5. The hinge socket 14 is fixed on the base 9 and located on one side of the V-block 10. One end of the hinge plate 11 is provided with a pin hole 15, and the other end of the hinge plate 11 is provided with a side slot 16. One end of the first hinge bolt 12 is connected to the pin hole 15 through a pin 17, and the other end of the first hinge bolt 12 is threadedly connected to the base 9. One end of the second hinge bolt 13 is connected to the hinge socket 14 through a pin 17, and the other end of the second hinge bolt can be embedded in the side slot 16 and threadedly connected to a clamping nut 18, which presses down on the hinge plate 11.
[0023] The device operates on the principle of laser triangulation to achieve high-precision positioning. A laser emitter generates a 635nm wavelength visible red laser beam, which, upon striking the surface of the thin-walled shell, forms a reflected spot. A position detector (PSD) monitors the positional changes of this reflected spot in real time, converting the optical signal into an electrical signal and transmitting it to the control unit. Based on the received deviation signal, the control system calculates the compensation amount using an algorithm and drives a lead screw adjustment mechanism via a servo motor, forming a complete closed-loop feedback system.
[0024] The laser emitter emits a visible laser beam, which is received by a PSD (Power Detector) chip. The PSD chip converts the geometric data into electrical signals, which are fed back to the controller via circuitry and processed by a microprocessor. Based on the calculation results, the position of the housing is adjusted to achieve the concentricity of the correction axis.
[0025] The workflow is as follows: 1. Initialization Phase 1) The servo motor performs a power-on self-test to confirm the zero-point position; 2) The laser emitter should be preheated for 15 minutes to reach a stable operating state; 3) The system performs automatic calibration, including laser optical path calibration, PSD zero-point calibration, and motion system homing; 4) Control software loads test parameters, including specimen size, material parameters, test procedures, etc.; 2. Calibration Phase 1) The laser beam irradiates the surface of the specimen, and the position of the reflected light spot is collected in real time by the PSD; 2) The control system calculates the deviation between the current position and the theoretical position; 3) Generate compensation commands based on the deviation amount to drive the servo motor for precise adjustment; 4) Repeat the detection-calculation-adjustment process until the positional deviation is ≤0.5μm; 3. Clamping stage 1) The hinged pressure plate opens, and the robotic arm automatically places the specimen; 2) The specimen is clamped by pressing down the hinge plate with the clamping nut. The pressure sensor monitors the clamping force in real time to ensure that it is within the set range (usually 50-100N). 3) After the system confirms that the specimen is securely fixed, it enters the test preparation state; 4. Testing Phase 1) The axial loading system applies compressive load at a set rate; 2) The laser measurement system monitors the displacement changes of the test piece in real time; 3) The data acquisition system synchronously records load-displacement data at a sampling rate of 1000Hz; 4) The system automatically stops the test when the specimen fails or the preset displacement is reached; Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.
Claims
1. A laser calibration device for axial compression testing of thin-walled shells, characterized in that: The system includes a laser calibrator system, a control unit, a servo motor, a lead screw adjustment mechanism, and a clamping mechanism. The laser calibrator system and the clamping mechanism are integrated into one unit. The control unit is electrically connected to the laser calibrator system, the servo motor, the lead screw adjustment mechanism, and the clamping mechanism to achieve closed-loop control. The laser calibrator system and the clamping mechanism use the same reference coordinate system. The clamping mechanism is used for non-destructive positioning and locking of the thin-walled shell. A pressure sensor is embedded in the clamping end face of the clamping mechanism. The pressure sensor is used to collect the locking force signal in real time and feed the signal back to the control unit. The servo motor is used to drive the lead screw adjustment mechanism. The laser calibrator system is used to monitor the displacement and positioning deviation of the thin-walled shell in real time, and works with the control unit, the servo motor, and the lead screw adjustment mechanism to complete dynamic calibration.
2. The laser calibration device for thin-walled shell axial compression testing according to claim 1, characterized in that: The laser calibration system includes a laser emitter, a position detector, a laser tracker, and a multi-axis robot. The laser emitter and the position detector are located on both sides of the clamping mechanism and connected to the lead screw adjustment mechanism. The lead screw adjustment mechanism can drive the laser emitter and the position detector to move synchronously. The laser tracker works in collaboration with the multi-axis robot to establish a three-dimensional coordinate system and achieve sub-millimeter-level positioning.
3. The laser calibration device for thin-walled shell axial compression testing according to claim 2, characterized in that: The laser emitter emits a visible red laser beam with a wavelength of 635 nm; the displacement measurement resolution of the position detector is 0.5 μm.
4. The laser calibration device for thin-walled shell axial compression testing according to claim 1, characterized in that: The laser calibration system includes a support frame, with a lead screw adjustment mechanism connected to each end of the support frame. The two lead screw adjustment mechanisms are driven by the same servo motor via a synchronous belt.
5. The laser calibration device for thin-walled shell axial compression testing according to claim 4, characterized in that: The clamping mechanism includes a base, a V-block, a hinge plate, a first hinge bolt, a second hinge bolt, and a hinge socket. The base is located at the bottom of the support frame. Two V-blocks are fixed side by side on the base. The V-grooves of the V-blocks are used to place thin-walled shells. The hinge socket is fixed on the base and located on one side of the V-blocks. One end of the hinge plate has a pin hole, and the other end of the hinge plate has a side slot. One end of the first hinge bolt is connected to the pin hole through a pin, and the other end of the first hinge bolt is threaded to the base. One end of the second hinge bolt is connected to the hinge socket through a pin, and the other end of the second hinge bolt can be embedded in the side slot and threaded to a clamping nut, which presses down on the hinge plate.