Flexible mechanism flexibility measuring device

Abstract

The invention belongs to the technical field of compliant mechanism performance testing, and particularly relates to a compliant mechanism flexibility measuring device. The device comprises a main body frame, a loading mechanism, a leveling mechanism and a loading head mechanism, the loading mechanism comprises a vertical loading assembly and a horizontal loading assembly; precise loading of six-dimensional force / torque is achieved through 12 steel belt loading points arranged on the support assembly; a steel belt force transmission mechanism is adopted to replace a traditional steel wire rope, additional torque is effectively avoided, and the accuracy of load transmission is guaranteed. The displacement measurement system is integrated on the bottom surface of the middle support, and synchronous detection of multi-dimensional deformation is realized through 12 measurement sites arranged on a loading head; the coaxial precision of a loading axis is ensured through a dual positioning system formed by the positioning column and the supporting frame. According to the invention, the technical problem of quantitative measurement of multi-dimensional flexibility parameters of the compliant mechanism is solved, and integrated measurement of six-dimensional force loading and multi-dimensional displacement detection is realized.

Description

Technical Field

[0001] This invention relates to the field of precision measurement technology, and in particular to a device for measuring the flexibility of a compliant mechanism. Background Technology

[0002] Compliant mechanism flexibility testing devices can quantitatively evaluate the flexibility of various materials and structures. Currently, they play an important role in product development and quality control in many industries. They can accurately capture minute mechanical changes in materials and transform subjective feelings such as "feel" and "compliance" that traditionally rely on experience into quantifiable physical parameters such as stiffness, softness, and coefficient of friction. This effectively avoids fluctuations and inconsistencies in human evaluation. Modern testing devices often adopt modular designs. Flexible material and device testing systems can integrate multiple testing modules such as mechanics, electricity, and optics, thereby completing multi-dimensional performance evaluation of materials on the same platform.

[0003] Existing compliant mechanism flexibility measuring devices have limited measurement dimensions, making them inconvenient for measuring composite loads.

[0004] A test bench for testing the performance of flexible steel cables is disclosed in Chinese patent document CN118857705A. This test bench includes a test frame with at least three skeletons arranged in three directions, each pair of skeletons having a predetermined angle. A return mechanism is mounted on one skeleton, and a handle assembly is mounted on another. A steel cable connects the return mechanism and the handle assembly. Fixing elements are provided on each skeleton to control the middle section of the steel cable, ensuring the steel cable is spatially arranged in at least three directions. This invention simulates the use of the steel cable in multiple directions and dimensions on an aircraft on the test bench to accurately measure the performance of the flexible steel cable, achieving comprehensive, multi-dimensional, real-time, and efficient performance evaluation of the aircraft's flexible steel cable, thereby ensuring the overall performance and safety of the aircraft. However, this test bench for testing the performance of flexible steel cables only simulates the spatial bending of the steel cable, with the load mainly being unidirectional tension, resulting in limited measurement accuracy.

[0005] A measuring rod flexibility coefficient measuring device and method are disclosed in Chinese patent document CN118883268A. This measuring rod flexibility coefficient measuring device and method includes a measuring device and a measuring rod fixing device. One end of the measuring rod is a measuring head, and the other end is a fixed end, which is mounted on the measuring rod fixing device. The measuring device includes a fixed frame, a moving frame, a first displacement sensor, and a force loading component. The fixed frame is fixed relative to the measuring rod fixing device. The moving frame is slidably or rotatably mounted on the fixed frame. The moving frame has a first contact component that contacts the measuring head of the measuring rod. The first displacement sensor is fixed relative to the fixed frame, and the measuring direction of the first displacement sensor is parallel to the sliding direction or the tangential direction of rotation of the moving frame. The force loading component can apply a force to the moving frame along the sliding direction or the tangential direction of rotation to deform the measuring rod. The first displacement sensor can measure the displacement. This invention measures the flexibility coefficient of the measuring rod based on the relationship between force and deformation. However, this measuring rod flexibility coefficient measuring device and method cannot accurately measure composite loads.

[0006] A flexible beam stiffness measuring device is disclosed in Chinese patent document CN204495642U. This device includes a loading joint, with a flexible beam loading end in the middle and weight-reducing mechanisms fixed at both ends. The loading end of the flexible beam has bosses at its upper and lower center positions, each boss having a swing bolt hole for mounting a swing bolt assembly. Connecting bolt holes for mounting connecting bolt assemblies are symmetrically located on both sides of the upper and lower bosses of the loading end. Torsion bolt holes for mounting torsion bolt assemblies are located at both ends of the weight-reducing mechanisms. All components of this invention are made of lightweight steel, and the weight-reducing holes and bosses are used effectively, resulting in a lighter weight and superior strength and stiffness characteristics compared to pine wood. This effectively avoids the cracking problem of the loading joint bolt holes that may occur when using pine wood. Furthermore, it considers an effective torque arm, eliminating the need for additional channel steel or other devices, thus completing various stiffness tests, simplifying the test installation workload and improving test accuracy. However, this flexible beam stiffness measuring device cannot measure the deformation during the measurement process.

[0007] To address the shortcomings of the existing technology, providing a device for measuring the flexibility of a compliant mechanism is a problem worthy of research. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of limited measurement dimensions and inconvenience in measuring composite loads, and to provide a compliant mechanism flexibility measuring device that achieves the technical effect of accurate loading of composite loads and strong load adaptability.

[0009] The objective of this invention is achieved through the following technical solution: A compliance mechanism flexibility measuring device includes a main frame and a compliance component to be measured, and further includes: The loading mechanism, located within the main frame, is used to apply multi-dimensional loads to the compliant component under test. A leveling mechanism located at the center of the main frame is used to install and level the tested compliant component. And a loading head mechanism disposed at the execution end of the loading mechanism, for connecting the free end of the compliant component under test and transmitting load; The loading mechanism includes a vertical loading component for applying vertical loads and a horizontal loading component for applying horizontal loads. The vertical loading component and the horizontal loading component are connected to the loading head mechanism via steel belts.

[0010] Optionally, the main framework includes: Four vertically arranged positioning posts constitute the main positioning chain of the device; A base support fixedly connected to the bottom of the positioning column; A side support fixedly connected to the middle of the side of the positioning column; A central support is fixedly connected between the positioning columns; And a top support fixedly connected to the top of the positioning column; The positioning columns pass through the leveling mechanism, the middle support, and the top support in sequence, forming a dual positioning system together with the support frame. The positioning columns pass through the leveling base, the middle support, and the top support, forming a secondary precise positioning. The dual positioning mechanism effectively ensures the stability and centering accuracy of the relative positions of each component. The four positioning columns pass through the middle support from the top support and are finally fixed to the leveling base, forming the main positioning chain to ensure the certainty of the relative position between the base and the main frame. In the non-measuring state, the middle support is connected to the loading head through the loading head positioning seat, so that the loading head is kept in the predetermined initial position.

[0011] Optionally, the loading mechanism further includes: Multiple support components arranged around the main frame; Each of the bracket components is fixedly connected to at least one of the vertical loading components and at least one of the horizontal loading components; Each of the support components has two vertical loading components fixedly connected to its top and a horizontal loading component fixedly connected to its middle, enabling unidirectional load loading as well as precise loading of composite loads (six-dimensional force / torque), and exhibiting excellent load adaptability.

[0012] Optionally, both the vertical loading component and the horizontal loading component include: A loading base is fixedly connected to the top of the support component; The position adjustment seat is fixedly connected to the top of the loading base; A fixed pulley is slidably connected to the top of the position adjustment seat; A steel belt fitted onto a fixed pulley; And the steel strip joint that is fixedly connected to the end of the steel strip; The steel strip joint is fixedly connected to the loading head mechanism. The position of the fixed pulley is adjusted by the position adjustment seat to control the loading direction of the steel strip. The position adjustment seat and the leveling base together constitute the adjustment system. The position adjustment seat is responsible for adjusting the main loading direction. The orthogonal series layout of the two can achieve fine-tuning of other degrees of freedom without frequent operation after the initial setting of the adjustment screw, ensuring the accuracy of the load direction.

[0013] Optionally, the leveling mechanism includes: Leveling shims are fixedly connected to the bottom of the main frame; A leveling base is fixedly connected to the top of the leveling pad, and the positioning post passes through the leveling base; A height adjustment base is fixedly connected to the top of the leveling base; The conforming component under test is fixed to the top of the height adjustment base. The leveling base has high rigidity, large mass and high flatness. The height adjustment base is replaced according to the height of the conforming component under test to achieve coarse adjustment. The leveling base is adjusted horizontally as a whole by leveling shims between its bottom surface and the base support.

[0014] Optionally, the loading head mechanism includes: Four loading head positioning seats are fixedly connected to the main frame; The loading head is fixed to the bottom of the loading head positioning seat by a connector, and the lower end face of the loading head is used to connect to the free end of the compliant part being tested. A horizontal displacement measuring component is fixedly connected to the upper surface of the loading head, and the horizontal displacement measuring component is used to measure horizontal displacement. And a vertical displacement measuring component fixedly connected to the upper surface of the loading head. The vertical displacement measuring component is used to measure vertical displacement. The measuring device is integrated into the bottom surface of the middle support. When the loading head generates displacement under load, the deformation can be directly and accurately captured by measuring elements such as sensors and dial indicators.

[0015] Optionally, the loading head mechanism further includes a clamping device for fixing the loading head during single-component loading, the clamping device comprising: Ball-head fixing seats are fixedly connected to the four corners of the top of the loading head; A positioning seat extension plate fixedly connected to the outside of the loading head positioning seat; A horizontal clamping head is installed on the loading head positioning seat, and the horizontal clamping head is used to clamp the ball head fixing seat in the horizontal direction; A downward clamping head is installed on the loading head positioning seat, and the downward clamping head is used to clamp the loading head downward; And an upward clamping head mounted on the positioning base extension plate, the upward clamping head being used to clamp the loading head upward.

[0016] Optionally, the clamping end of the horizontal clamping head acts on the side of the ball head fixing seat, the clamping end of the downward clamping head acts on the top surface of the loading head, and the clamping end of the upward clamping head acts on the bottom surface of the loading head, together achieving complete constraint on the space of the loading head. This can effectively suppress unnecessary deformation in other directions and ensure measurement accuracy when performing single-component load loading and displacement measurement.

[0017] Positive and beneficial effects: 1. This compliant mechanism flexibility measuring device can achieve single-direction load loading and also accurately load composite loads (six-dimensional force / torque), possessing excellent load adaptability. It uses a steel belt to transmit the load, providing good centering guidance and uniform and stable force distribution. Compared to steel wire rope, the steel belt does not generate additional torque under tension, thus significantly improving the accuracy of load application. Furthermore, the measuring device is integrated into the bottom surface of the central support. When the loading head displaces under load, the deformation can be directly and accurately captured by sensors, dial indicators, and other measuring elements. The device clearly distinguishes between the loading point, displacement measurement point, and constraint point. The ample point design not only meets various measurement needs but also allows for improved measurement reliability through data cross-verification and can be flexibly configured according to actual working conditions.

[0018] 2. This compliant mechanism flexibility measuring device uses a positioning column as the core to form the main positioning chain, supplemented by an auxiliary positioning chain of the supporting frame. This dual positioning system effectively ensures the coaxiality of the system and can compensate for and correct cumulative errors generated during processing and manufacturing. The steel strip joint is ingeniously designed; the adjusting threaded hole of its outer shell can be used to fix the middle shell and finely adjust the angle to ensure smooth passage of the steel strip. The guide groove height of the horizontal loading head is aligned with the upper surface of the mechanism under test, avoiding additional torque introduced by the offset of the loading point. The threaded hole of the middle shell is used to reliably clamp the steel strip, while the internal arc surface guides the steel strip to bend smoothly, preventing it from bending and deforming.

[0019] 3. This compliant mechanism flexibility measuring device consists of a position adjustment seat and a loading base, forming an adjustment system. The position adjustment seat is responsible for adjusting the main direction of the load. The orthogonal series connection of the two allows for fine-tuning of other degrees of freedom via adjusting screws (requiring no frequent operation after initial setting), ensuring the accuracy of the load direction. The loading base uses pin positioning, corner screw tightening, and bottom leveling shims for height adjustment to ensure long-term horizontality. Its thick cast iron structure provides extremely high basic rigidity, establishing a stable and accurate reference plane for all components above.

[0020] 4. This compliant mechanism flexibility testing device achieves coarse height adjustment by equipping it with height-adjustable bases of different specifications, and fine adjustment by combining this with the small-range fluctuation of the steel strip joint itself. This design allows the device to quickly adapt to the testing needs of compliant mechanisms of different heights. Attached Figure Description

[0021] Figure 1 This is a schematic diagram showing the overall view of the compliance mechanism flexibility measuring device of the present invention; Figure 2 This is a schematic diagram of the equipment in the middle of the device (without a clamping device); Figure 3 This is a schematic diagram of the main equipment in the flexible middle section of the compliant mechanism; Figure 4 This is a schematic diagram of the loading head and clamping device; Figure 5 A schematic diagram of the connection between the loading head and the central support (bottom view); Figure 6 This is a schematic diagram of the lower surface of the loading head; Figure 7 This is a schematic diagram of the arrangement of unidirectional steel strip joints; Figure 8 Schematic diagram of steel strip joint parts; Figure 9 This is a schematic diagram of a fixed pulley position adjustment device; Figure 10 This is a schematic diagram of the leveling device for the leveling base.

[0022] In the diagram: 1. Main frame; 101. Positioning column; 102. Basic support; 103. Side support; 104. Middle support; 105. Top support; 2. Loading mechanism; 201. Vertical loading assembly; 202. Horizontal loading assembly; 203. Position adjustment seat; 204. Fixed pulley; 205. Steel belt; 206. Support assembly; 207. Steel belt joint; 208. Loading base; 3. Leveling mechanism; 301. Leveling base; 302. Height adjustment base; 303. Compliant part to be measured; 304. Leveling shims; 4. Loading head mechanism; 401. Loading head; 402. Horizontal displacement measuring component; 403. Vertical displacement measuring component; 404. Loading head positioning seat; 405. Ball head fixing seat; 406. Positioning seat extension plate; 407. Horizontal clamping head; 408. Downward clamping head; 409. Upward clamping head. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] Example 1 like Figures 1 to 10 As shown, a compliance mechanism flexibility measuring device includes a main frame 1 and a compliance component 303 to be measured, and further includes: The loading mechanism 2, which is set inside the main frame 1, is used to apply multi-dimensional loads to the compliant component 303 under test. The leveling mechanism 3, located at the center of the main frame 1, is used to install and level the compliant component 303 to be tested. And the loading head mechanism 4, which is located at the end of the loading mechanism 2, is used to connect the free end of the compliant part 303 under test and transmit the load; The loading mechanism 2 includes a vertical loading component 201 for applying vertical loads and a horizontal loading component 202 for applying horizontal loads. The vertical loading component 201 and the horizontal loading component 202 are connected to the loading head mechanism 4 via a steel belt 205.

[0025] like Figure 1 and Figure 2 As shown, the main frame 1 includes: Four vertically arranged positioning posts 101 constitute the main positioning chain of the device; A base support 102 is fixedly connected to the bottom of the positioning column 101; Side support 103 is fixedly connected to the middle of the side of the positioning column 101; A central support 104 is fixedly connected between the positioning columns 101; and a top support 105 fixedly connected to the top of the positioning column 101; Positioning posts 101 pass through the leveling mechanism 3, the middle support 104, and the top support 105 in sequence, forming a dual positioning system together with the support frame. Positioning posts 101 pass through the leveling base 301, the middle support 104, and the top support 105, forming a secondary precise positioning. The dual positioning mechanism effectively ensures the stability and centering accuracy of the relative positions of each component. The four positioning posts 101 pass through the middle support 104 from the top support 105 and are finally fixed to the leveling base 301, forming the main positioning chain to ensure the certainty of the relative position between the base and the main frame. In the non-measuring state, the middle support is connected to the loading head 401 through the loading head positioning seat 404, so that the loading head is kept in the predetermined initial position. The two positioning chains are as follows: the main positioning chain: the leveling base 301 is fixed to four positioning posts 101 by threaded connection. The positioning posts 101 are connected to the middle support 104 by graphite copper sleeves and screws. The middle support 104 is connected to the loading head positioning seat 404 by pins and bolts. The loading head positioning seat 404 fixes the loading head 401 by screws. The loading head 401 is then connected to the tested compliant part 303 by pins and bolts. Finally, it is reconnected to the leveling base 301 through the tested compliant part 303 itself and the height adjustment base 302, forming a closed-loop main positioning path. Auxiliary positioning chain: The leveling base 301 is connected to the base support 102, side support 103, middle support 104 and upper support 105 in sequence by pins and bolts, and then connected to the tested compliant part 303 through the loading head positioning seat 404 and the loading head 401. Finally, it is connected back to the leveling base 301 through the tested compliant part 303 and the height adjustment base 302, forming an auxiliary positioning loop to further enhance the overall stability of the system.

[0026] Example 2 like Figure 1 As shown, the loading mechanism 2 also includes: Multiple support components 206 are arranged around the main frame 1; Each support assembly 206 is fixedly connected to at least one vertical loading assembly 201 and at least one horizontal loading assembly 202, which can realize load loading in a single direction, and can also perform precise loading of composite loads (six-dimensional force / torque), and has excellent load adaptability.

[0027] like Figure 1 and Figure 9 As shown, both the vertical loading component 201 and the horizontal loading component 202 include: The loading base 208 is fixedly connected to the top of the support component 206; Position adjustment seat 203 is fixedly connected to the top of loading base 208; A fixed pulley 204 is slidably connected to the top of the position adjusting seat 203; A steel belt 205 fitted onto a fixed pulley 204; And a steel strip joint 207 fixedly connected to the end of the steel strip 205; The steel strip joint 207 is fixedly connected to the loading head mechanism 4. The position of the fixed pulley 204 is adjusted by the position adjustment seat 203 to control the loading direction of the steel strip 205. The position adjustment seat 203 and the loading base 208 together form an adjustment system. The position adjustment seat 203 is responsible for adjusting the main loading direction. The orthogonal series layout of the two can achieve fine-tuning of other degrees of freedom without frequent operation after the initial setting of the adjustment screw, ensuring the accuracy of the load direction. Due to the different load directions, the steel strip joint structures used are divided into horizontal and vertical types. The horizontal steel strip joint 207 is set on the lower surface of the loading head 401, and the vertical steel strip joint 207 is set on the upper and lower surfaces 504 of the loading head 401. There are twelve steel strip loading points to realize the simulation of force load in six dimensions. The steel strip is used to transfer the load, which has good centering guidance and uniform and stable force. Compared with steel wire rope, the steel strip will not generate additional torque when under tension, thus significantly improving the accuracy of load application. Furthermore, the steel strip joint 207 is ingeniously designed. The adjusting threaded hole on its outer housing can be used to fix the middle housing and fine-tune the angle to ensure smooth passage of the steel strip. The guide groove height of the horizontal loading head is aligned with the upper surface of the mechanism under test, avoiding additional torque introduced by the offset of the loading point. The threaded hole in the middle housing is used to reliably clamp the steel strip, while the inner arc surface guides the steel strip to bend smoothly, preventing it from bending or deforming.

[0028] Example 3 like Figures 2 to 10 As shown, the leveling mechanism 3 includes: Leveling pads 304 are fixedly connected to the bottom of the main frame 1; A leveling base 301 is fixedly connected to the top of the leveling pad 304, and a positioning post 101 passes through the leveling base 301. A height adjustment base 302 is fixedly connected to the top of the leveling base 301; The conforming part 303 under test is fixed on the top of the height adjustment base 302. The leveling base 301 has high rigidity, large mass and high flatness. The height adjustment base 302 is replaced according to the height of the conforming part 303 under test to achieve coarse adjustment. The leveling base 301 is adjusted horizontally as a whole by the leveling shims 304 between its bottom surface and the base support 102. Furthermore, the leveling base 301 employs pin positioning, corner screw tightening, and bottom leveling shims 304 for height adjustment to ensure lasting horizontality. Its thick cast iron structure provides extremely high foundation rigidity, establishing a stable and precise reference plane for all components above. Coarse height adjustment is achieved by equipping it with height-adjusting bases 302 of different specifications, and fine adjustment is performed by combining this with the small-range fluctuation of the steel strip joint 207 itself. This design allows the device to quickly adapt to the testing requirements of compliant mechanisms at different heights.

[0029] Example 4 like Figures 2 to 10 As shown, the loading head mechanism 4 includes: Four loading head positioning seats 404 are fixedly connected to the main frame 1; The loading head 401 is fixed to the bottom of the loading head positioning seat 404 by a connector, and the lower end face of the loading head 401 is used to connect to the free end of the compliant part 303 to be tested. A horizontal displacement measuring component 402 is fixedly connected to the upper surface of the loading head 401. The horizontal displacement measuring component 402 is used to measure horizontal displacement. And a vertical displacement measuring component 403 fixedly connected to the upper surface of the loading head 401. The vertical displacement measuring component 403 is used to measure vertical displacement. The measuring device is integrated into the bottom surface of the middle support. When the loading head generates displacement under load, the deformation can be directly and accurately captured by measuring elements such as sensors and dial gauges.

[0030] like Figure 4 and Figure 6 As shown, the loading head mechanism 4 also includes a clamping device for fixing the loading head 401 during single-component loading, the clamping device comprising: Ball head fixing seats 405 are fixedly connected to the four corners of the top of the loading head 401; Positioning seat extension plate 406 is fixedly connected to the outside of the loading head positioning seat 404; The horizontal clamping head 407 is installed on the loading head positioning seat 404. The horizontal clamping head 407 is used to clamp the ball head fixing seat 405 in the horizontal direction. The downward clamping head 408 is installed on the loading head positioning seat 404 and is used to clamp the loading head 401 downward. And an upward clamping head 409 installed on the positioning base extension plate 406, the upward clamping head 409 being used to clamp the loading head 401 upward.

[0031] like Figure 4 and Figure 6As shown, the clamping end of the horizontal clamping head 407 acts on the side of the ball head fixing seat 405, the clamping end of the downward clamping head 408 acts on the top surface of the loading head 401, and the clamping end of the upward clamping head 409 acts on the bottom surface of the loading head 401. Together, they achieve complete constraint on the space of the loading head 401. This can effectively suppress unnecessary deformation in other directions when performing single-component load loading and displacement measurement, thus ensuring measurement accuracy.

[0032] Example 5 A method for measuring the flexibility of a compliant mechanism 1. Preliminary preparations: Due to differences in device installation and environment, displacement calibration and force calibration are required before formal use. The displacement calibration process is as follows: Replace the test piece with a workpiece of known flexibility; the installation process is consistent with the formal measurement process. The load application method is consistent with the experimental requirements (e.g., apply a uniaxial load for unidirectional force, and a composite load for composite force). The load magnitude is determined based on the upper and lower limits of the load during actual measurement and the known flexibility of the workpiece. Multiple calibration tests are performed. Read the displacement values ​​obtained from the calibration, calculate the ratio to the expected displacement value, and calculate the corrected parameters based on this ratio (i.e., k = ax1 + ax2 + b). Subsequent experimentally measured displacements must be corrected to obtain the measured values. The force calibration process is as follows: A high-precision standard force gauge is installed in the measuring device, positioned between the loading head and the supporting structure, ensuring that the force transmission path is consistent with that of the formal measurement. The loading system of the driving device is activated to apply a load of the same type as in the formal experiment, starting from zero and gradually increasing the load to the upper limit of the formal experiment using equal gradients or equal intervals, and then gradually unloading. This process should be repeated multiple times to improve data reliability. Under each load level, two values ​​are recorded simultaneously: one is the force value output by the device control system, and the other is the actual force value measured by the standard force gauge. Through data processing, a correction relationship between the command output force value and the actual force value is fitted.

[0033] Before measurement, check the connection status of the entire device to ensure that all connections are tight and free from movement. If the test piece includes connecting parts, tighten them as well.

[0034] Adjust the leveling base 301 and the loading head 401 to a parallel state. Adjust the level of the base using the leveling shim 304, and assist in leveling by fine-tuning the connecting screws of the loading head positioning seat 404.

[0035] Install a height adjustment base 302 that matches the height of the compliance mechanism under test.

[0036] 2. Install the compliance component 303 under test: Place the compliance component 303 to be tested in the predetermined position and ensure that it is securely connected to the height adjustment base 302.

[0037] Adjust the height of the loading head 401 by adjusting the connecting screws of the loading head positioning seat 404, ensuring that the gap between its bottom surface and the bottom surface of the compliant part 303 being tested is less than 0.05mm. This can be verified using a feeler gauge of appropriate thickness; the gauge should not be able to be inserted. Ensure that the loading head is not in contact with the compliant part being tested at this time.

[0038] 3. Connection and fixation steps for single-component loading only: The angle of the compliant component 303 around the vertical axis is used to initially position the loading head 401 and the compliant mechanism using a pin.

[0039] The loading head 401 is pre-fixed laterally, downward, and upward using the tightening head in sequence.

[0040] Then connect the loading head 401 to the tested compliant part 303 with bolts; at this point, tightening is not required.

[0041] Remove the connecting screws between the loading head 401 and the loading head positioning seat 404, and then thoroughly tighten the connecting bolts between the loading head and the compliant mechanism.

[0042] Confirm that the loading head 401 has been securely secured by all clamping devices and connectors.

[0043] 4. Preparations before load loading: Loosen the clamping device in the direction of the target deformation. If displacement is required in the vertical direction, the effect of the loading head's own weight must be considered when loosening the upward clamping head 409.

[0044] Using tools such as a level, the relative positions of the fixed pulley 204 and the steel belt joint 207 in the vertical and horizontal loading components are detected and adjusted. The accuracy of the horizontal or vertical loading direction is ensured by operating the position adjustment seat 203.

[0045] Before the formal loading, a small load can be applied first, and then removed after the measurement readings stabilize, thereby eliminating the instability of the flexible element near the zero position.

[0046] 5. Measurement execution: A specified load is applied by a load-applying device.

[0047] At the same time, the corresponding displacement data is read through the horizontal displacement measuring device 402 and the vertical displacement measuring device 403.

[0048] 6. Measurement End and Reset: First, tighten the connecting screws between the loading head 401 and the loading head positioning seat 404. No need to tighten them.

[0049] Remove the bolts and pins connecting the loading head to the tested compliant part 303.

[0050] Loosen all clamping devices.

[0051] Subsequently, the connecting screws of the adjustable loading head positioning seat 404 are used to raise the loading head. Finally, the connection between the tested compliant part 303 and the height adjustment base 302 is disconnected, and the tested part can be removed.

[0052] Precautions: 1. Before measurement, be sure to tighten all connecting parts from the fixed bottom surface of the compliant mechanism to the loading end face to minimize the measurement error introduced by the connection gap.

[0053] 2. When installing the positioning post 101, the smoothness with which it passes through each support component should be used as the basis for judging the installation accuracy. If the installation is obstructed, it indicates that there may be machining or positioning deviations in the frame. In this case, the positioning post should be reliably connected to the base first, and then the positions of the upper and middle supports should be fine-tuned using it as a reference.

[0054] 3. To reduce systematic errors, a fixed pulley of size 204 with a large diameter and light weight should be selected to reduce friction; at the same time, if space permits, a longer steel belt should be used as much as possible to reduce systematic errors in the deformation measurement of the compliant mechanism.

[0055] 4. The clamping force of the clamping head on the loading head 401 should not be too large, so as to avoid the constraint device itself interfering with the free deformation of the mechanism.

[0056] 5. The clamping device is only used when applying a single component load. When applying a multi-component composite load, all clamping constraints should be released.

[0057] 6. The position adjustment seat 203 and the leveling base 301 must be orthogonally connected in series. During commissioning, it is recommended to use a laser collimator or laser tracker to calibrate the pulley block to accurately control the direction of load application.

[0058] The above is only used to illustrate the technical solution of the present invention and not to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention, as long as they do not depart from the spirit and scope of the technical solution of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A device for measuring the flexibility of a compliant mechanism, comprising a main frame (1) and a compliant component to be measured (303), characterized in that, Also includes: The loading mechanism (2) is set inside the main frame (1) to apply multi-dimensional loads to the compliant component (303) under test; The leveling mechanism (3) is located at the center of the main frame (1) and is used to install and level the tested compliance component (303). And a loading head mechanism (4) disposed at the execution end of the loading mechanism (2) for connecting the free end of the tested compliant member (303) and transmitting load; The loading mechanism (2) includes a vertical loading component (201) for applying vertical loads and a horizontal loading component (202) for applying horizontal loads. The vertical loading component (201) and the horizontal loading component (202) are connected to the loading head mechanism (4) via a steel strip (205).

2. The compliant mechanism flexibility measuring device according to claim 1, characterized in that, The main framework (1) includes: Four vertically arranged positioning posts (101) constitute the main positioning chain of the device; A base support (102) is fixedly connected to the bottom of the positioning column (101); Side support (103) fixedly connected to the middle of the side of the positioning column (101); A central support (104) is fixedly connected between the positioning columns (101). And a top support (105) fixedly connected to the top of the positioning post (101); The positioning column (101) passes through the leveling mechanism (3), the middle support (104) and the top support (105) in sequence, forming a dual positioning system together with the support frame.

3. The compliant mechanism flexibility measuring device according to claim 1, characterized in that, The loading mechanism (2) also includes: Multiple support components (206) arranged around the main frame (1); Each of the support components (206) is fixedly connected to at least one of the vertical loading components (201) and at least one of the horizontal loading components (202).

4. The compliant mechanism flexibility measuring device according to claim 3, characterized in that, Both the vertical loading component (201) and the horizontal loading component (202) include: A loading base (208) is fixedly connected to the top of the support assembly (206); A position adjustment seat (203) is fixedly connected to the top of the loading base (208); The fixed pulley (204) is slidably connected to the top of the position adjustment seat (203); A steel belt (205) fitted onto a fixed pulley (204); And a steel strip joint (207) fixedly connected to the end of the steel strip (205); The steel strip joint (207) is fixedly connected to the loading head mechanism (4), and the position of the fixed pulley (204) is adjusted by the position adjustment seat (203) to control the loading direction of the steel strip (205).

5. The compliant mechanism flexibility measuring device according to claim 1, characterized in that, The leveling mechanism (3) includes: The leveling pad (304) is fixedly connected to the bottom of the main frame (1). A leveling base (301) is fixedly connected to the top of the leveling pad (304), and the positioning post (101) passes through the leveling base (301). A height adjustment base (302) is fixedly connected to the top of the leveling base (301); The tested compliance component (303) is fixed to the top of the height adjustment base (302).

6. The compliant mechanism flexibility measuring device according to claim 1, characterized in that, The loading head mechanism (4) includes: Four loading head positioning seats (404) are fixedly connected to the main frame (1); The loading head (401) is fixed to the bottom of the loading head positioning seat (404) by a connector, and the lower end face of the loading head (401) is used to connect to the free end of the compliant part (303) under test. A horizontal displacement measuring component (402) is fixedly connected to the upper surface of the loading head (401), and the horizontal displacement measuring component (402) is used to measure horizontal displacement; And a vertical displacement measuring component (403) fixedly connected to the upper surface of the loading head (401), the vertical displacement measuring component (403) being used to measure vertical displacement.

7. The compliant mechanism flexibility measuring device according to claim 6, characterized in that, The loading head mechanism (4) further includes a clamping device for fixing the loading head (401) during single-component loading, the clamping device comprising: Ball head fixing seats (405) are fixedly connected to the four corners of the top of the loading head (401); A positioning seat extension plate (406) is fixedly connected to the outside of the loading head positioning seat (404). A horizontal clamping head (407) is installed on the loading head positioning seat (404), and the horizontal clamping head (407) is used to clamp the ball head fixing seat (405) in the horizontal direction. A downward clamping head (408) is installed on the loading head positioning seat (404), and the downward clamping head (408) is used to clamp the loading head (401) downward. And an upward clamping head (409) mounted on the positioning seat extension plate (406), the upward clamping head (409) being used to clamp the loading head (401) upward.

8. The compliant mechanism flexibility measuring device according to claim 7, characterized in that: The clamping end of the horizontal clamping head (407) acts on the side of the ball head fixing seat (405), the clamping end of the downward clamping head (408) acts on the top surface of the loading head (401), and the clamping end of the upward clamping head (409) acts on the bottom surface of the loading head (401), together achieving complete constraint on the space of the loading head (401).

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