Dual range multi-dimensional force sensor

Abstract

The utility model provides a kind of double range multi-dimensional force sensor, including the measurement module with common central axis, force range-increasing elastic plate and moment range-increasing elastic plate, and it is provided with circumferential gap and axial gap between measurement module, force range-increasing elastic plate and moment range-increasing elastic plate, to realize the overload protection of force at the central axis of elastomer;When the size of circumferential gap and axial gap is all greater than zero, multi-dimensional force sensor is at first range, when the size of circumferential gap and axial gap exists zero, the force / torque measurement of zero gap corresponding direction of multi-dimensional force sensor is at second range.The utility model provides by increasing range-increasing device, forms new multi-dimensional force sensor, so that it has high sensitivity, low stiffness low range and low sensitivity, high stiffness high range, effectively increases the stiffness of sensor, its structure is simple, overload protection effect is good, no coupling and no influence to measurement accuracy, to solve the problem of influence to force sensor measurement accuracy.

Description

Technical Field

[0001] This utility model relates to the field of sensor application technology, and in particular to a dual-range multi-dimensional force sensor. Background Technology

[0002] With the continuous development of robotics technology, the demand for force control at the end effector of robots is increasing. Due to the complexity of the working environment, six-dimensional force sensors not only need high sensitivity but also need to prevent failure due to overload under extreme conditions such as impact. The overload protection capability of a six-dimensional force sensor is usually determined by the stiffness of the elastic body. Increasing the stiffness of the elastic body can improve the overload protection capability of the sensor; however, it cannot measure the force and torque under overload conditions during impact.

[0003] Currently, improving the overload protection capability of sensors mainly lies in the design of the sensor elastomer in the early stage. Changing the material or structure of the elastomer can improve the overall stiffness of the sensor to a certain extent, but this will directly affect the sensitivity of the elastomer, and thus affect the measurement accuracy of the elastomer. At present, the emergence of overload protection devices has alleviated the failure of sensors due to overload to a certain extent, but the sensor cannot perform measurements within the overload protection range.

[0004] It should be noted that the information disclosed in the above background section is only used to enhance the understanding of the background of this utility model and does not constitute any limitation on this utility model. Utility Model Content

[0005] In view of the shortcomings of the prior art described above, this utility model provides a dual-range multidimensional force sensor. By adding a range extender, a new multidimensional force sensor is formed, which has a low range with high sensitivity and low stiffness, and a high range with low sensitivity and high stiffness. Without affecting the measurement of the multidimensional force sensor, the stiffness of the sensor is effectively increased. Its structure is simple, the overload protection effect is good, there is no coupling and it does not affect the measurement accuracy, so as to solve the problem of affecting the measurement accuracy of the force sensor.

[0006] This utility model provides a dual-range multi-dimensional force sensor, comprising:

[0007] The measurement module includes a loading end for load force and / or torque, an elastic body for measuring force or torque, and a support end connected to a mounting base;

[0008] A force-extending elastic plate, comprising a first end extending toward a loading end and a second end connected to a support end;

[0009] A torque-extending elastic plate is located between the measuring module and the torque-extending elastic plate, and includes a first end connected to the loading end and a second end away from the loading end;

[0010] The measuring module, force-extending elastic plate, torque-extending elastic plate, and elastic body share a common central axis, and circumferential and axial clearances are provided between the measuring module, force-extending elastic plate, and torque-extending elastic plate.

[0011] Overload protection against force is achieved by setting circumferential and / or axial gaps near the central axis of the elastic body. When the loading end and / or the torque-extending elastic plate comes into contact with the force-extending elastic plate, it generates a corresponding force on the elastic body but no torque.

[0012] The circumferential gap and / or axial gap provided on the outside of the elastic body are used to protect the torque. When the support end, the force-extending elastic plate and the torque-extending elastic plate are in contact, the torque-extending elastic plate is subjected to a couple and only generates a corresponding torque on the elastic body without exerting any force.

[0013] When both the circumferential and axial clearances are greater than zero, the multidimensional force sensor is in its first range. When both the circumferential and axial clearances are zero, the force / torque measurement in the direction corresponding to the zero clearance of the multidimensional force sensor is in its second range.

[0014] In one embodiment of the present invention, the first end of the torque-extending elastic plate is connected to the loading end. When the multi-dimensional force sensor is in the second range under the action of bending torque, one side of the second end of the torque-extending elastic plate is in axial contact with the support end or the torque-extending elastic plate, and the other side of the second end of the torque-extending elastic plate, which is symmetrical about the central axis of the elastic body, is also in axial contact with the torque-extending elastic plate or the support end.

[0015] In one embodiment of the present invention, the first end of the torque-extending elastic plate is connected to the loading end. When the multidimensional force sensor is in the second range under the action of torsional torque, one side of the second end of the torque-extending elastic plate is in circumferential contact with the support end and / or the torque-extending elastic plate. The other side of the second end of the torque-extending elastic plate, which is symmetrical about the central axis of the elastic body, is also in circumferential contact with the support end and / or the torque-extending elastic plate.

[0016] In one embodiment of the present invention, the second end of the force-extending elastic plate is connected to the support end. When the multi-dimensional force sensor is in the second range under the action of circumferential force, the first end of the force-extending elastic plate is in circumferential contact with the loading end and / or the torque-extending elastic plate, and the line connecting the equivalent point of action of the circumferential contact force and the equivalent point of the circumferential force measurement of the elastic body is perpendicular to the central axis of the elastic body.

[0017] In one embodiment of the present invention, the second end of the force-extending elastic plate is connected to the support end. When the multi-dimensional force sensor is in the second range under the action of axial force, the first end of the force-extending elastic plate is in axial contact with the loading end and / or the torque-extending elastic plate, and the equivalent point of action of the axial contact force coincides with the central axis of the elastic body.

[0018] In one embodiment of the present invention, a circumferential gap t1 is formed between the first end of the force-extending elastic plate and the first end and / or the loading end of the torque-extending elastic plate; a circumferential gap t4 is formed between the second end of the torque-extending elastic plate and the support end and / or the second end of the force-extending elastic plate.

[0019] In one embodiment of the present invention, an axial gap t2 is formed between the first end of the force-extending elastic plate and the first end and / or the loading end of the torque-extending elastic plate; an axial gap t3 is formed between the second end of the torque-extending elastic plate and the second end and the support end of the force-extending elastic plate.

[0020] In one embodiment of this utility model, the planes forming the limiting gaps between the measuring module, the force-extending elastic plate, and the torque-extending elastic plate are parallel to each other, and the curved surfaces forming the limiting gaps are coaxial with each other.

[0021] In one embodiment of the present invention, the elastomer is disposed between the loading end and the supporting end.

[0022] In one embodiment of the present invention, the elastomer includes at least one of a three-beam structure, a cross-beam structure, a multi-beam structure, an E-type diaphragm structure, and a Stewart structure.

[0023] The beneficial effects of this invention are as follows: By integrating a force-extending elastic plate and a torque-extending elastic plate into a traditional sensor structure, and coordinating with a set gap control, the working mode switching is achieved. Under low load conditions, the system maintains high sensitivity and low stiffness characteristics; when the load exceeds a set threshold, the force-extending and torque-extending elastic plates automatically intervene to form a high-stiffness load-bearing path, increasing the overall stiffness of the sensor. This not only provides overload protection but also allows for continued measurement, achieving dual-range measurement. Its structure is simple and reliable, achieving automatic switching solely through a mechanical structure, eliminating the need for a complex control system. Independent limit mechanisms in each dimension achieve non-coupling overload protection between dimensions. Furthermore, a symmetrical contact design and a special position contact design ensure that torque overload protection has no effect, and force overload protection has no torque effect, thus providing a guarantee for dual-range measurement. Coupling errors are controlled to ensure the continuity of the measurement signal during range switching. Therefore, while maintaining measurement accuracy, reliability and environmental adaptability are improved.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the present invention. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments conforming to the present invention and, together with the description, serve to explain the principles of the present invention. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0026] Figure 1 This is a schematic diagram of the structure of the dual-range multi-dimensional force sensor of this utility model;

[0027] Figure 2 This is a schematic diagram of the split structure of the dual-range multi-dimensional force sensor of this utility model;

[0028] Figure 3 This is a schematic diagram of the measurement module in this utility model;

[0029] Figure 4 This is a schematic diagram of the upper base structure in this utility model;

[0030] Figure 5 This is a schematic diagram of the structure of the force-extending elastic plate of this utility model;

[0031] Figure 6 This is a schematic diagram of the torque-extending elastic plate in this utility model;

[0032] Figure 7 This is a schematic diagram showing the position of the equivalent point of application under the circumferential force measurement state in this utility model;

[0033] Figure 8 This is a cross-sectional view of the dual-range multi-dimensional force sensor of this utility model, showing the limiting gap in one embodiment.

[0034] Figure 9 This is a cross-sectional view showing the limiting gap in one embodiment of the dual-range multi-dimensional force sensor of this utility model.

[0035] In the diagram: 100, mounting base; 100a, upper base; 101a, support plate one; 102a, support plate two; 103a, groove; 100b, lower base; 101, limiting post; 10, measuring module; 11, loading end; 12, elastic body; 120, through hole; 13, support end; 20, force-extending elastic plate; 201, support plate; 202, stepped shaft; 21, limiting block; 30, torque-extending elastic plate; 300, limiting hole; 31, spoke; 310, through groove. Detailed Implementation

[0036] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. It should also be understood that the terminology used in the embodiments of this utility model is for describing specific implementation schemes and not for limiting the scope of protection of this utility model.

[0037] Please see Figures 1 to 9 It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms used in this specification regarding position, quantity, etc., are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to these relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention's implementation.

[0038] Please see Figures 1 to 9 This utility model provides a dual-range multi-dimensional force sensor, comprising:

[0039] The measurement module 10 includes a loading end 11 for load force and / or torque, an elastic body 12 for measuring force or torque, and a support end 13 connected to the mounting base 100.

[0040] Force-extending elastic plate 20, which includes a first end extending toward the loading end 11 and a second end connected to the support end 13;

[0041] The torque extender elastic plate 30 is located between the measuring module 10 and the force extender elastic plate 20, and includes a first end connected to the loading end 11 and a second end away from the loading end 11.

[0042] The measuring module 10, force-extending elastic plate 20, torque-extending elastic plate 30, and elastic body 12 share a common central axis. A circumferential gap and an axial gap are provided between the measuring module 10, force-extending elastic plate 20, and torque-extending elastic plate 30. The gap at the central axis of the elastic body 12 provides overload protection against force. When the loading end 11 and / or the torque-extending elastic plate 30 contact the force-extending elastic plate 20, they exert a corresponding force on the elastic body 12 without exerting a torque. The circumferential gap and / or axial gap on the outside of the elastic body 12 protect against torque. When the support end 13, force-extending elastic plate 20, and torque-extending elastic plate 30 contact, they only exert a corresponding torque on the elastic body 12 without exerting a force.

[0043] When both the circumferential and axial clearances are greater than zero, the multidimensional force sensor is in its first range. When both the circumferential and axial clearances are zero, the force / torque measurement in the direction corresponding to the zero clearance of the multidimensional force sensor is in its second range.

[0044] Specifically, in this embodiment of the invention, the dual-range multi-dimensional force sensor operates through the coordinated operation of the measurement module 10 and the range extender. The measurement module 10 includes a loading end 11, an elastic body 12, and a support end 13, forming a basic force / torque sensing unit. The range extender consists of a force-extending elastic plate 20 and a torque-extending elastic plate 30, which achieve automatic range switching through designed circumferential and axial clearances. This structural layout ensures measurement accuracy under low loads, provides reliable overload protection under high loads, and allows for continued measurement, thus achieving dual-range measurement.

[0045] Please see the appendix Figures 1 to 4 As shown, the mounting base 100 may include an upper base 100a and a lower base 100b. The measuring module 10 is assembled in the upper base 100a and then connected to the torque extender elastic plate 20. The torque extender elastic plate 20 is bolted to the lower base 100b. That is, the measuring module 10 can be connected to the support plate 101a of the upper base 100a through its support end 13, and the connection is achieved by bolts along the bolt holes. Similarly, corresponding bolt holes can also be made on the torque extender elastic plate 30 and the torque extender elastic plate 20, which will not be described in detail here.

[0046] Please see the appendix Figures 5 to 9As shown, the first end of the force-extending elastic plate 20 can be a stepped shaft 202, and its second end can be a surrounding support plate 201. The first end of the torque-extending elastic plate 30 can be a boss structure (not shown in the figure), and its second end can be a spoke structure 31. The limiting post 101 can be installed in the groove 103a of the support plate 102a in the upper base 100a, thereby realizing the assembly of the torque-extending elastic plate 30 and its limiting gap. The limiting post 101 can also be installed on the lower base 100b or on the force-extending elastic plate 20.

[0047] In the first range, i.e., the low-range operating mode, all gaps remain open, and the external load is entirely borne by the elastic body 12. The elastic body 12 can be designed with low stiffness, allowing it to generate significant strain signals from relatively small forces or torques, thus providing the sensor with extremely high sensitivity when measuring small forces and torques. As the load increases to a certain level, the corresponding gaps gradually close, and the force-extending elastic plate 20 and the torque-extending elastic plate 30 begin to participate in load-bearing, achieving overload protection and providing the basic conditions for dual-range measurement. It should be noted that the symmetrical protection structure ensures that the contact points are symmetrically distributed under overload conditions, preventing torque overload protection from taking effect, while maintaining consistent stiffness under both positive and negative forces or torques, providing the necessary conditions for dual-range measurement.

[0048] Thus, dual-range operation is achieved through adaptive switching of the structure's elastic properties, eliminating the need for additional electronic control devices. This also improves the sensor's overload capacity while maintaining measurement accuracy. Furthermore, the use of elastic materials in the cushioning design gives the sensor a certain degree of shock resistance, thereby extending its service life. This makes the sensor suitable for applications requiring both measurement accuracy and reliability, such as force control systems for collaborative robots.

[0049] Please see Figures 3 to 9 In one embodiment, the first end of the torque-extending elastic plate 30 is connected to the loading end 11. When the multidimensional force sensor is in the second range under the action of bending torque, one side of the second end of the torque-extending elastic plate 30 is in axial contact with the support end 13 or the force-extending elastic plate 20, and the other side of the second end of the torque-extending elastic plate 30, which is symmetrical about the central axis of the elastic body 12, is also in axial contact with the force-extending elastic plate 20 or the support end 13. For example, when an excessive torque in the Mx direction is applied to the multidimensional force sensor, the torque-extending elastic plate 30 will rotate with the elastic body 12 around the x-axis (i.e., the radial direction of the multidimensional force sensor corresponding to the Mx direction). One side of the plate will bend upward and make axial contact with the support end 13, and the corresponding other side will bend downward and make axial contact with the force-extending elastic plate 20 or the support end 13; or, one side of the plate will bend upward and make axial contact with the force-extending elastic plate 20, and the corresponding other side will bend downward and make axial contact with the force-extending elastic plate 20 or the support end 13.

[0050] In one embodiment, the first end of the torque-extending elastic plate 30 is connected to the loading end 11. When the multidimensional force sensor is in the second range under the action of torsional torque, one side of the second end of the torque-extending elastic plate 30 is in circumferential contact with the support end 13 and / or the force-extending elastic plate 20, and the other side of the second end of the torque-extending elastic plate 30, which is symmetrical about the central axis of the elastic body 12, is also in circumferential contact with the support end 13 and / or the force-extending elastic plate 20. That is, when an excessive torque in the Mz direction is applied to the multidimensional force sensor, the torque-extending elastic plate 30 will rotate along the z-axis (i.e., axial direction) with the elastic body 12, with one side in circumferential contact with the support end 13 and / or the force-extending elastic plate 20, and the other side also in circumferential contact with the support end 13 and / or the force-extending elastic plate 20.

[0051] In one embodiment, the second end of the force-extending elastic plate 20 is connected to the support end 13. When the multidimensional force sensor is in its second range under the action of circumferential force, the first end of the force-extending elastic plate 20 is in circumferential contact with the loading end 11 and / or the torque-extending elastic plate 30, and the line connecting the equivalent point of application of the circumferential contact force and the equivalent point of circumferential force measurement on the elastic body 12 is perpendicular to the central axis of the elastic body 12. That is, when an excessive force in the Fx direction is applied to the multidimensional force sensor, the first end of the force-extending elastic plate 20 is in circumferential contact with the loading end 11 and / or the torque-extending elastic plate 30, and the force generated by the contact only exerts a force on the elastic body and does not exert a torque on the elastic body. The measured value of the multidimensional force sensor is the actual magnitude of the force in the Fx direction.

[0052] Specifically, please refer to the appendix. Figure 7 For example, P1 is the equivalent point position of the measuring force Fx of the elastic body, P2 is the position of the equivalent concentrated force at the contact point when the overload protection in the Fx direction occurs on the cylindrical profile surface, that is, the equivalent point position of the circumferential contact force, L1 is the line connecting the two equivalent point positions, L0 is the central axis of the elastic body 12, and L1 is located on a plane perpendicular to L0.

[0053] In one embodiment, the second end of the force-extending elastic plate 20 is connected to the support end 13. When the multidimensional force sensor is in its second range under axial force, the first end of the force-extending elastic plate 20 is in axial contact with the loading end 11 and / or the torque-extending elastic plate 30, and the equivalent point of application of the axial contact force coincides with the central axis of the elastic body 12. That is, when an excessive force in the Fz direction is applied to the multidimensional force sensor, the first end of the force-extending elastic plate 20 is in axial contact with the loading end 11 and / or the torque-extending elastic plate 30, which can be in positive or negative contact, and the point of application of the equivalent concentrated force at the contact point is located on the central axis.

[0054] Please see Figures 3 to 9In one embodiment, the measuring module 10 has a through hole 120 on its central axis, the first end of the torque-extending elastic plate 30 is connected in the through hole 120, the torque-extending elastic plate 30 has a limiting hole 300 on the central axis of its first end, the first end of the torque-extending elastic plate 20 extends through the limiting hole 300 into the through hole 120, and a circumferential gap t1 is formed between the first end of the torque-extending elastic plate 20 and the limiting hole 300 and / or the through hole 120.

[0055] Specifically, in this embodiment of the invention, the measuring module 10 adopts a layout with a central shaft through-hole 120. Specifically, the through-hole 120 opened along the central axis of the elastic body 12 not only reduces the overall weight but also provides a positioning reference for the installation of the torque-extending elastic plate 30. The first end of the torque-extending elastic plate 30 is embedded in the through-hole 120, ensuring the straightness and stability of the force transmission path. At the central axis position of the first end of the torque-extending elastic plate 30, a limiting hole 300 structure is designed accordingly. The diameter of this hole is slightly larger than the outer diameter of the first end of the torque-extending elastic plate 30, forming a precisely controlled circumferential gap t1 between them. The size of the circumferential gap t1 has been calculated and experimentally verified to ensure the normal operation of the torque-extending elastic plate 30 in the first range (low range) and to achieve reliable measurement in the second range (high range) when the circumferential gap t1 disappears and limiting contact occurs.

[0056] Thus, through the cooperation of the through hole 120 and the limiting hole 300, precise alignment of the three key components—elastic body 12, torque-extending elastic plate 30, and force-extending elastic plate 20—is achieved. Simultaneously, the presence of the circumferential clearance t1 allows relative movement of the components under low loads, avoiding unnecessary coupling interference. Furthermore, when the load increases to a set threshold, the closure of the circumferential clearance t1 immediately forms a new force transmission path, achieving automatic stiffness enhancement. Utilizing the inherent characteristics of the mechanical structure, automatic range switching can be achieved without additional control components.

[0057] Furthermore, the measuring module 10 and the range extender are designed to fit together coaxially. The central shaft through-hole 120 of the measuring module 10 and the limiting hole 300 of the torque extender elastic plate 30 are machined coaxially to ensure uniform sidewall clearance between them. In the assembled state, the first end of the torque extender elastic plate 20 extends precisely through the limiting hole 300 into the through-hole 120, and a uniform circumferential clearance t1 is formed between its outer surface and the inner wall of the limiting hole 300 and / or the through-hole 120.

[0058] The circumferential gap formed between the first end of the force-extending elastic plate 20 and the limiting hole 300 of the torque-extending elastic plate 30 and / or the through hole 120 of the elastic body 12 constitutes a radial limiting system. When the sensor is subjected to a radial force in the direction of Fx or Fy, the first end of the force-extending elastic plate 20 will contact the inner wall of the limiting hole 300 and / or the through hole 120, and the line connecting the point of application of the equivalent concentrated force of the circumferential contact force and the point of application of the equivalent point of circumferential force measurement of the elastic body 12 is perpendicular to the central axis of the elastic body 12. At the same time, the equivalent concentrated force always passes through the central axis. In one embodiment, the point of application of the equivalent concentrated force is exactly located on the axial symmetry plane of the beam of the elastic body 12 that senses the force. This fundamentally avoids the generation of additional coupling torques My or Mx, and of course, there is no effect of Mz. Secondly, the symmetrically arranged contact points keep the radial force transmission path balanced and will not cause the elastic body 12 to be deformed by off-center loading. Furthermore, this design ensures that the linearity of the measurement signal is maintained when the sensor switches from a low range to a high range, i.e., the second range, avoiding the problem of measurement failure when traditional overload protection occurs.

[0059] Furthermore, for example, in precision robotic assembly operations, when a robotic arm experiences a radial collision, the sensor can immediately switch to a high-stiffness range while maintaining the independence between each measurement dimension and continuing the low-coupling performance of the low-range measurement. For instance, during spacecraft docking, even under significant radial impact forces, the overload protection device will not generate interfering torques that affect docking accuracy. Test data shows that sensors with this design maintain the linearity of radial force measurement before and after range switching, and the coupling error is always controlled within the required range.

[0060] Please see Figure 2 , Figure 5 , Figures 8 to 9 In one embodiment, the first end of the force-extending elastic plate 20 is also connected to a limiting block 21, and the outer diameter of the limiting block 21 is larger than the outer diameter of the first end of the force-extending elastic plate 20, and an axial gap t2 is formed between the limiting block 21 and the end face of the torque-extending elastic plate 30 and / or between the limiting block 21 and the end face of the loading end 11.

[0061] Specifically, in this embodiment of the invention, a limiting block 21 is provided at the first end of the force-extending elastic plate 20, and is made larger than the outer diameter of the first end of the force-extending elastic plate 20 or the through hole 120, thus forming a mechanical stop. This creates an axial gap t2 between the limiting block 21 and the end face of the torque-extending elastic plate 30, or between the limiting block 21 and the end face of the loading end 11, ensuring both measurement freedom at low ranges and timely and effective axial limiting during overload.

[0062] It should be noted that the limiting block 21 at the first end of the force-extending elastic plate 20, along with the axial gap formed near the central axis by the torque-extending elastic plate 30 and the loading end 11, are arranged on both sides, with the gap values ​​at both ends remaining consistent. This ensures that the point of application of the axial force Fz is always located at the center of the multi-dimensional force sensor, avoiding torque generation caused by off-center loading. Furthermore, the uniform arrangement of the end face gaps allows the sensor to be evenly stressed when subjected to axial impact, preventing localized contact. This ensures that the sensor does not generate additional interfering torque when axial overload protection is triggered, guaranteeing the independence of each measurement dimension. The upper and lower gap settings ensure overload protection and measurement of both positive and negative axial forces Fz.

[0063] Thus, when the robot is performing precision assembly operations and encounters an unexpected axial impact, the sensor can immediately switch to a high-rigidity range while maintaining the continuity of the measurement signal. This effectively absorbs the axial vibration impact during the launch process, protecting the core sensing components from damage.

[0064] Please see Figure 2 , Figures 6 to 9 In one embodiment, an axial gap t3 is formed between the second end of the torque-extending elastic plate 30 and the second end of the force-extending elastic plate 20 and the support end 13.

[0065] Specifically, in this embodiment of the invention, a double-sided clearance design is adopted at the second end of the torque-extending elastic plate 30. By controlling the axial clearance t3, protection against bending moment loads is achieved. The axial clearance t3 arranged on both sides of the shaft allows the elastic body 12 to deform freely within the first range, ensuring measurement sensitivity. On the other hand, it can form a rigid support in time during overload, generating a couple effect to effectively resist the overturning moment without generating the Fz force, thus providing a basic guarantee for the normal measurement of Fz in the second range.

[0066] Thus, in practical applications, such as when industrial robots perform high-precision assembly, it can effectively suppress the interfering torque generated by tool deflection. Similarly, it can be used in wind turbine monitoring to withstand large-amplitude alternating torques generated by blade oscillation. The multi-dimensional force sensor structure in this embodiment ensures that its torque measurement error meets performance requirements when overload protection in the Mx or My direction is triggered, thereby improving measurement reliability under complex torque environments.

[0067] Please see Figures 6 to 9 In one embodiment, a through groove 310 is provided on the second end of the torque-extending elastic plate 30, and a limiting post 101 corresponding to the through groove 310 is provided on the mounting base 100, and a circumferential gap t4 is formed between the limiting post 101 and the through groove 310.

[0068] Specifically, in this embodiment of the present invention, a through groove 310 is opened in the structure of the second end of the torque-extending elastic plate 30 to cooperate with the limiting post 101 on the mounting base 100, and the adaptation to complex torque loads is achieved by controlling its circumferential clearance t4.

[0069] It should be noted that the symmetrical structure around the torque extender elastic plate 30 and the circumferential gaps formed with the corresponding positions of the support end 13 and / or the torque extender elastic plate 20 constitute a torsional torque limiting system. This system achieves circumferential limiting in the Mz direction through multiple symmetrically distributed contact points, generating a torque couple without generating Fx or Fy forces, thus providing a fundamental guarantee for the normal measurement of Fx or Fy forces in the second range. Furthermore, the symmetrical structure ensures a consistent limiting effect even under torque overload in any direction.

[0070] Thus, during aerospace docking, multi-directional interference torques can be effectively suppressed. In the precision operation of industrial robots, it can withstand the dynamic torque of tools. When the overload protection in the Mz direction is triggered, the torque measurement error of the dual-range multi-dimensional force sensor is controlled within the required range ratio, improving measurement reliability under complex working conditions. This extends the sensor's lifespan and significantly improves the safety and accuracy of the force control system.

[0071] Please see Figures 8 to 9 In one embodiment, the planes forming the limiting gaps between the measuring module 10, the force-extending elastic plate 20, and the torque-extending elastic plate 30 are parallel to each other, and the curved surfaces forming the limiting gaps are coaxial with each other.

[0072] Specifically, in this embodiment of the invention, the structural fit between the measuring module 10 and the force-extending elastic plate 20 and torque-extending elastic plate 30 of the range extender is constrained by corresponding limiting gaps. The limiting function is achieved through parallelism and coaxiality control, thereby providing a stable and reliable limiting reference. The limiting between parallel planes, i.e., the axial clearance, ensures the accuracy of the load transmission direction and avoids the generation of unexpected lateral forces. The coaxial curved surface fit structure ensures ideal guidance for each component during relative movement, preventing jamming. Furthermore, dimensional parameter control ensures the consistency of all limiting gaps, giving the sensor uniform overload protection across all measurement dimensions. This ensures that during range switching, each component maintains the correct relative position, avoiding measurement errors caused by geometric deviations.

[0073] In this way, the size of the limit gap can remain stable during continuous operation and cyclic testing of industrial robots, thereby ensuring the sensor maintains stable limit performance under various working environments. This guarantees the reliability and safety of the control system, as well as the possibility of dual-range measurement. This solves the accuracy loss problem of traditional sensors during range switching and provides a foundation for the long-life design of high-precision force measurement equipment.

[0074] Please see Figures 1 to 3 In one embodiment, the elastomer 12 is disposed between the loading end 11 and the supporting end 13. The elastomer 12 includes at least one of a three-beam structure, a cross-beam structure, a multi-beam structure, an E-type diaphragm structure, and a Stewart structure.

[0075] Specifically, in this embodiment of the invention, the elastomer 12 adopts a modular structure, achieving a balance between measurement performance and structural strength through optimized layout. As the core component of the sensor, the elastomer 12 has two ends rigidly connected to the support end 13 and the loading end 11, respectively, forming a complete force transmission chain. This connection method ensures effective load transmission and provides stable boundary conditions for strain measurement. It should be noted that the elastomer 12 can be flexibly configured in various ways, such as a three-beam structure, a cross-beam structure, a multi-beam structure, an E-type diaphragm structure, or a Stewart structure, depending on the needs of different application scenarios. Each configuration has undergone corresponding mechanical optimization design. The elastomer 12 can also be integrated with the mounting base as a single unit.

[0076] More specifically, the three-beam configuration employs three cantilever beams symmetrically distributed at 120°, exhibiting superior force-strain linearity. The cross-beam structure achieves multidimensional force decoupling through orthogonally arranged double beams. The E-type diaphragm structure utilizes the uniform deformation characteristics of its annular thin wall to enhance measurement sensitivity. The Stewart configuration achieves precise six-dimensional force measurement through a spatially symmetrical six-branch layout. All these elastomer structures can be constructed from aluminum alloys, titanium alloys, or other alloy steels, undergoing special heat treatment processes to ensure stable mechanical properties under long-term cyclic loading.

[0077] Thus, when the modular elastomer 12 is applied in the field of industrial robots, the crossbeam structure can achieve sufficiently high measurement accuracy. A multi-beam structure can also be used for larger loads. The corresponding Stewart configuration can withstand extreme impact loads. Under precision assembly conditions, the E-type diaphragm structure can achieve high-precision measurement of minute forces. By adopting an optimized elastomer 12 structure, the sensor's zero-point drift still meets measurement accuracy requirements after fatigue cycle testing, significantly improving the sensor's long-term stability.

[0078] In summary, this utility model provides a dual-range multi-dimensional force sensor that integrates a force-extending elastic plate and a torque-extending elastic plate into a traditional sensor structure, achieving switching of operating modes through gap control. Under low-load conditions, the system maintains high sensitivity and low stiffness characteristics; when the load exceeds a set threshold, the force-extending and torque-extending elastic plates of the range extender automatically intervene to form a high-stiffness load-bearing path, increasing the overall stiffness of the sensor and effectively resisting high-load impact loads. Its structure is simple and reliable, achieving automatic switching solely through mechanical structures without the need for a complex control system; overload protection is achieved using independent limit mechanisms in each dimension; and a symmetrical contact design controls coupling errors, ensuring the continuity of the measurement signal during range switching. Thus, while maintaining measurement accuracy, it improves reliability and environmental adaptability, providing an ideal solution for precision force control in fields such as robotics and aerospace.

[0079] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

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