Six-dimensional force sensor static calibration device and system

Abstract

The invention relates to a six-dimensional force sensor static calibration device and system.The six-dimensional force sensor static calibration device comprises a stress beam which is of a centrosymmetric cross-shaped structure and is parallel to a horizontal calibration plate, and the stress beam comprises a center part connected to a six-dimensional force sensor and four extension arms connected to the center part; the axial direction of the central part is defined as a Z axis, the four extension arms are circumferentially arrayed relative to the Z axis, each wall surface of each extension arm in the circumferential direction of the extension arm is provided with at least one loading part, and the loading parts on the two extension arms in the same axial direction are symmetrically distributed relative to the Z axis; and the multiple loading assemblies are in one-to-one correspondence with the multiple loading parts, and the loading assemblies are configured to be used for applying calibration loads to the loading parts in the direction perpendicular to the corresponding wall faces of the extension arms. According to the static calibration device for the six-dimensional force sensor, the calibration efficiency and the calibration precision of the six-dimensional force sensor can be effectively improved.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a static calibration device and system for a six-dimensional force sensor. Background Technology

[0002] Force sensors are key sensing components in fields such as robotics, precision assembly, aerospace, and biomechanics. They are used to detect and measure the forces and torques acting on objects and are widely used in end-effectors such as dexterous hands, robotic arms, and collaborative robots. Among them, six-dimensional force sensors, which can simultaneously detect forces (Fx, Fy, Fz) and torques (Mx, My, Mz) in three orthogonal directions, have become core components of intelligent equipment and advanced sensing systems because they provide the most comprehensive force information.

[0003] The calibration device for a six-dimensional sensor is a classic static calibration method that calibrates the six-dimensional force / torque measurement accuracy of the six-dimensional force sensor by applying a force / torque of known magnitude and direction. It establishes a mapping relationship between the output signal of the six-dimensional force sensor and the actual load, thereby correcting the measurement error.

[0004] In related technologies, the calibration device for six-dimensional sensors has structural defects. It can only apply positive or negative loads in a single dimension and cannot apply loads in two or more dimensions simultaneously. In order to meet the calibration requirements of forces / torques of different directions and magnitudes, it is necessary to frequently change the clamping tools or change the clamping method, which is cumbersome, inefficient and has low calibration accuracy. Summary of the Invention

[0005] This application aims to at least address one of the technical problems existing in the prior art. To this end, this application provides a static calibration device and system for a six-dimensional force sensor, which can effectively improve the calibration efficiency and accuracy of the six-dimensional force sensor.

[0006] In a first aspect, this application provides a static calibration device for a six-dimensional force sensor, comprising:

[0007] Platform;

[0008] The first support assembly includes a first support frame vertically mounted on the bearing platform and a horizontal calibration plate disposed on the first support frame, wherein the horizontal calibration plate is used to fix the six-dimensional force sensor;

[0009] The force-bearing beam has a centrally symmetrical cross-shaped structure and is parallel to the horizontal calibration plate. The force-bearing beam includes a central part connected to the six-dimensional force sensor and four extension arms connected to the central part. The axis of the central part is defined as the Z-axis. The four extension arms are arranged in a circular array about the Z-axis. Each extension arm has at least one loading part on each wall surface along its own circumference. The loading parts on two extension arms on the same axis are symmetrically distributed with respect to the Z-axis.

[0010] Multiple loading components, each corresponding to one of the multiple loading parts, are configured to apply a calibration load to the loading part in a direction perpendicular to the corresponding wall surface of the extension arm.

[0011] The six-dimensional force sensor static calibration device according to the first aspect of this application has at least the following beneficial effects:

[0012] The six-dimensional force sensor static calibration device of this application, through the coordinated arrangement of a bearing platform, a first support component, a force-bearing beam, and multiple loading components, uses at least one loading part on the circumferential wall surface of each of the four orthogonally positioned extension arms on the force-bearing beam. A single loading component can be selected to apply a standard load perpendicular to the wall surface of the corresponding extension arm to the loading part on that wall surface. Through the force transmission effect of the force-bearing beam, the unidirectional axial force along the X / Y / Z direction and the unidirectional torque around the X / Y / Z direction of the six-dimensional force sensor can be applied. Alternatively, two loading components can be selected simultaneously to apply a standard load perpendicular to the wall surface of the corresponding loading parts of symmetrical extension arms, achieving simultaneous loading of the forward and reverse axial forces along the X / Y / Z direction and the forward and reverse torques around the X / Y / Z direction. Multiple loading components can also be selected to simultaneously apply standard loads perpendicular to the wall surface of the corresponding loading parts of different extension arms, achieving simultaneous loading of forces and torques in multiple dimensions. This effectively improves the calibration efficiency and accuracy of the six-dimensional force sensor.

[0013] In some embodiments, it further includes: four second support frames, vertically mounted on the bearing platform and located around the first support assembly, the four second support frames being arranged in a circular array about the Z-axis;

[0014] The loading assembly includes a pulley system, a fixed boss, a pull rope, and a weight. The fixed boss is located on the second support frame. At least one pulley on the pulley system is rotatably mounted on the fixed boss. The pull rope is wound around the pulley on the pulley system and is detachably connected to the loading part. The free end of the pull rope can be kept in a plumb bob state under the constraint of the pulley system and the fixed boss. The weight is used to hang on the free end of the pull rope.

[0015] In some embodiments, the fixing bosses on all loading components extend horizontally, and the fixing bosses on at least three loading components are spaced apart along the height direction of the second support frame, and the length of all the fixing bosses on each second support frame decreases along the height direction of the second support frame.

[0016] In some embodiments, at least two opposing second support frames are provided with three fixed bosses spaced apart in the horizontal direction, and the load-bearing beam is at the same height as the three fixed bosses spaced apart in the horizontal direction.

[0017] In some embodiments, the first support frame includes two opposing vertical positioning plates and a horizontal bearing plate connected between the two vertical positioning plates, wherein the horizontal calibration plate is connected between the two vertical positioning plates and located below the horizontal bearing plate.

[0018] In some embodiments, in any of the loading components, when the position of the fixed boss relative to the bearing platform is higher than the position of the load-bearing beam relative to the bearing platform, at least one pulley on the pulley block is rotatably disposed on the surface of the horizontal bearing plate near the load-bearing beam; when the position of the fixed boss relative to the bearing platform is lower than the position of the load-bearing beam relative to the bearing platform, at least one pulley on the pulley block is rotatably disposed on the surface of the horizontal calibration plate away from the load-bearing beam.

[0019] In some embodiments, the horizontal calibration plate has a plurality of first clearance holes for the pull rope to pass through, and the plurality of first clearance holes are arranged in a circular array about the Z-axis; the vertical positioning plate has a plurality of second clearance holes for the pull rope to pass through, and the plurality of second clearance holes are distributed at intervals along the height direction.

[0020] In some embodiments, the second support frame has multiple weight-reduction holes.

[0021] In some embodiments, the loading portion is provided at the center of the central portion, and one of the loading components applies a calibration load along the Z-axis to the loading portion at the center.

[0022] Secondly, this application provides a six-dimensional force sensor static calibration system, which includes the six-dimensional force sensor static calibration device described above.

[0023] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0025] Figure 1 This is a schematic diagram of the structure of a six-dimensional force sensor static calibration device according to an embodiment of this application.

[0026] Figure 2 for Figure 1 A magnified view of a portion of point A in the middle.

[0027] Figure 3 This is a schematic diagram of the left side of the static calibration device for a six-dimensional force sensor according to an embodiment of this application.

[0028] Figure 4 This is a front view structural diagram of the six-dimensional force sensor static calibration device according to an embodiment of this application.

[0029] Figure 5 This is a schematic diagram of the cooperation structure between the load-bearing beam and the six-dimensional force sensor in an embodiment of this application.

[0030] Figure 6 This is a schematic diagram of the cooperation structure between the load-bearing beam and the six-dimensional force sensor in an embodiment of this application, viewed from another perspective.

[0031] Figure 7 This is a partial structural diagram of the six-dimensional force sensor static calibration device according to an embodiment of this application. Figure 1 .

[0032] Figure 8 This is a partial structural diagram of the six-dimensional force sensor static calibration device according to an embodiment of this application. Figure 2 .

[0033] Figure 9 This is a partial structural diagram of the six-dimensional force sensor static calibration device according to an embodiment of this application. Figure 3 .

[0034] Explanation of reference numerals in the attached drawings: First support assembly 100; First support frame 110; Vertical positioning plate 111; Second clearance hole 1111; Horizontal bearing plate 112; Horizontal calibration plate 120; First clearance hole 121; Force-bearing beam 200; Central part 210; Extension arm 220; Loading part 230; Loading assembly 300; Pulley block 310; Pulley 311; Fixed boss 320; Pull rope 330; Second support frame 400; Weight reduction hole 410; Bearing platform 500; Six-dimensional force sensor 600. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0037] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0039] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0041] The calibration device for a six-dimensional sensor is a classic static calibration method that calibrates the six-dimensional force / torque measurement accuracy of the six-dimensional force sensor by applying a force / torque of known magnitude and direction. It establishes a mapping relationship between the output signal of the six-dimensional force sensor and the actual load, thereby correcting the measurement error.

[0042] In related technologies, the calibration device for six-dimensional sensors has structural defects. It can only apply positive or negative loads in a single dimension and cannot apply loads in two or more dimensions simultaneously. In order to meet the calibration requirements of forces / torques of different directions and magnitudes, it is necessary to frequently change the clamping tools or change the clamping method, which is cumbersome, inefficient and has low calibration accuracy.

[0043] Based on this, this application provides a static calibration device for a six-dimensional force sensor. This device, through the coordinated arrangement of a support platform, a first support component, a force-bearing beam, and multiple loading components, uses at least one loading portion provided on the circumferential walls of four orthogonally positioned extension arms on the force-bearing beam. A single loading component can be selected to apply a standard load perpendicular to the wall surface to the loading portion on the corresponding wall surface of the corresponding extension arm. Through the force transmission action of the force-bearing beam, the device achieves unidirectional axial force along X / Y / Z and circumferential force on the six-dimensional force sensor. For unidirectional torque loading in the Y / Z direction, two loading components can be selected to simultaneously apply a standard load perpendicular to the wall surface of the corresponding wall of the symmetrical extension arm. This allows for the synchronous loading of the positive and negative axial forces along the X / Y / Z direction and the synchronous loading of the positive and negative torques around the X / Y / Z direction of the six-dimensional force sensor. Alternatively, multiple loading components can be selected to simultaneously apply a standard load perpendicular to the wall surface of the corresponding wall of different extension arms, according to actual calibration requirements. This enables the simultaneous loading of forces and torques in multiple dimensions, effectively improving the calibration efficiency and accuracy of the six-dimensional force sensor.

[0044] See Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 This application provides a six-dimensional force sensor static calibration device, including a bearing platform 500, a first support component 100, a force-bearing beam 200, and multiple loading components 300.

[0045] The first support assembly 100 includes a first support frame 110 vertically mounted on the bearing platform 500 and a horizontal calibration plate 120 disposed on the first support frame 110. The horizontal calibration plate 120 is used to fix the six-dimensional force sensor 600.

[0046] The load-bearing beam 200 has a centrally symmetrical cross-shaped structure and is parallel to the horizontal calibration plate 120. The load-bearing beam 200 includes a central part 210 connected to the six-dimensional force sensor 600 and four extension arms 220 connected to the central part 210. The axial direction of the central part 210 is defined as the Z-axis. The four extension arms 220 are arranged in a circular array about the Z-axis. Each extension arm 220 has at least one loading part 230 on each wall surface along its own circumference. The loading parts 230 on two extension arms 220 on the same axial direction are symmetrically distributed with respect to the Z-axis.

[0047] Multiple loading components 300 correspond one-to-one with multiple loading parts 230. The loading components 300 are configured to apply a calibration load to the loading parts 230 in a direction perpendicular to the corresponding wall surface of the extension arm 220.

[0048] It should be noted that in this application, the bearing platform 500 refers to the support and bearing base of this calibration device, which is used to provide accurate positioning and stable bearing for components such as the first support component 100, the load-bearing beam 200, and the loading component 300, so that the load-bearing beam 200 will only undergo a preset deformation when subjected to the calibration load applied by the loading component 300, without any additional displacement or shaking.

[0049] In this application, for the first support assembly 100, the first support frame 110 can be vertically installed at the center of the bearing platform 500 to provide a positioning reference for the installation of other components. The first support frame 110 is a rectangular frame structure formed by connecting multiple connecting plates. The middle part of the first support frame 110 is through-hole along its length or width direction, that is, the middle part of the first support frame 110 is hollow, which facilitates the transfer of calibration load between the loading assembly 300 and the load-bearing beam 200. The horizontal calibration plate 120 can be fixed to the first support frame 110 by welding, threading, etc., and is located in the hollow space in the middle of the first support frame 110. The horizontal calibration plate 120 is used to independently fix the six-dimensional force sensor 600. In this application, the six-dimensional force sensor 600 has a cylindrical or rectangular structure. The upper and lower ends of the six-dimensional force sensor 600 are its lower cover and upper cover, respectively. The lower cover of the six-dimensional force sensor 600 is fixed to the horizontal calibration plate 120 by screws or bolts, so that the six-dimensional force sensor 600 maintains a stable state parallel to the horizontal calibration plate 120.

[0050] In this application, for the load-bearing beam 200, the central portion 210 of the load-bearing beam 200 can be connected to the upper cover of the six-dimensional force sensor 600 by screws or bolts, so that the load-bearing beam 200 as a whole maintains a stable parallel state with the six-dimensional force sensor 600. It can be understood that after the horizontal calibration plate 120, the six-dimensional force sensor 600, and the load-bearing beam 200 are positioned and assembled, the axial direction of the load-bearing beam 200, the axial direction of the six-dimensional force sensor 600, and the axial direction of the horizontal calibration plate 120 coincide.

[0051] See Figure 5 and Figure 6 The axis of the central part 210 is defined as the Z-axis. The circular array of the four extension arms 220 about the Z-axis can be understood as follows: the axis of the central part 210 of the load-bearing beam 200 is defined as the Z-axis of the spatial rectangular coordinate system. The axes of any two adjacent extension arms 220 connected to the central part 210 are the X-axis and Y-axis of the spatial rectangular coordinate system, respectively. That is, the four extension arms 220 are orthogonally distributed to form a "+" shape. The center of the central part 210 is the origin of the spatial rectangular coordinate system. The four extension arms 220 are the positive X-axis, positive Y-axis, negative X-axis, and negative Y-axis, respectively.

[0052] See Figure 5 and Figure 6On the load-bearing beam 200, its central part 210 and four extension arms 220 are integrally formed structures. Both the central part 210 and the extension arms 220 are rectangular bodies. When one end of the extension arm 220 is connected to the central part 210, the wall surface where the end is located forms an interface with the central part 210. The wall surface of the extension arm 220 along its own circumference is the other five wall surfaces excluding the interface between the extension arm 220 and the central part 210. At least one loading part 230 is provided on each of the five wall surfaces.

[0053] The symmetrical distribution of loading portions 230 on two extension arms 220 located on the same axial direction relative to the Z-axis can be understood as follows: the loading portions 230 on the two extension arms 220 located in the positive and negative X-axis directions are mirror-symmetrical with respect to the Z-axis; similarly, the loading portions 230 on the two extension arms 220 located in the positive and negative Y-axis directions are mirror-symmetrical with respect to the Z-axis; for example, a loading portion 230 is provided on each wall surface of the extension arm 220 located in the positive X-axis direction, and a loading portion 230 is also provided at the corresponding position on each wall surface of the extension arm 220 located in the negative X-axis direction, and the arrangement of the loading portions 230 on the other two extension arms 220 is similar.

[0054] In this application, the number of loading components 300 is equal to the number of loading parts 230.

[0055] The loading assembly 300 is configured to apply a calibrated load to the loading portion 230 in a direction perpendicular to the corresponding wall surface of the extension arm 220. This can be understood as: see Figure 1 and Figure 5 Taking the positive X-axis, negative X-axis, positive Y-axis, negative Y-axis, positive Z-axis, and negative Z-axis as the forward, backward, left, right, up, and down directions respectively, and taking the extension arm 220 in the positive X-axis direction as an example, the extension arm 220 in the positive X-axis direction has a front wall, a left wall, a rear wall, an upper wall, and a lower wall along its circumference. Each of the front, left, right, upper, and lower wall surfaces is provided with a loading part 230. The corresponding loading assembly 300 can apply a forward standard load to the loading part 230 on the front wall, thereby applying a positive axial force Fx (X-axis torque). The corresponding loading assembly 300 can apply a leftward standard load to the loading part 230 on the left wall. When a positive torque Mz (torque about the Z-axis) is applied, the corresponding loading component 300 can apply a standard load to the right of the loading part 230 on the right wall to apply a negative axial force Mz. The corresponding loading component 300 can apply an upward standard load to the loading part 230 on the upper wall to apply a positive torque My (torque about the Y-axis). The corresponding loading component 300 can apply a downward standard load to the loading part 230 on the lower wall to apply a negative torque My. The same applies to applying standard loads to the loading parts 230 on the other extension arms 220.

[0056] The loading component 300 can be a combination structure of pulley block 310, pull rope 330 and weight. The end of the pull rope 330 is vertically connected to the loading part 230 on the corresponding wall surface of the extension arm 220. The free end of the pull rope 330 is hung with a standard value of weight. The pulley block 310 is used to transmit the load of the pull rope 330. The value of the weight corresponds to the standard load applied to the loading part 230. The size of the standard load is adjusted by reducing the weight on the free end of the pull rope 330 and changing the value of the weight. In this way, the target force / torque is calibrated. In this embodiment, the loading part 230 can be constructed as a locking device, which can fix and lock or release the end of the pull rope 330.

[0057] Of course, in other embodiments, the loading component 300 may also be a hydraulically driven force loader, an electrically servo-driven force loader, etc., and there is no specific limitation.

[0058] The six-dimensional force sensor static calibration device of this application embodiment calibrates the six-dimensional force sensor 600 according to the following principle: A standard load perpendicular to the wall surface is applied to the loading part 230 on the corresponding wall surface of the corresponding extension arm 220 on the force beam 200 by the loading component 300. Utilizing the force transmission effect of the force beam 200, force and torque are applied to the six-dimensional force sensor 600 along a preset direction. By selecting one or more loading components 300, the loading component 300 applies a standard load perpendicular to the wall surface to the loading part 230 on the corresponding wall surface of different extension arms 220, thereby changing the magnitude and direction of the standard load applied to the six-dimensional force sensor 600, achieving independent and coupled loading of the six-dimensional force. The controller of the six-dimensional force sensor static calibration device can output corresponding channel signals according to the magnitude and direction of the force sensor 600, establishing a mapping relationship between the channel signals output by the six-dimensional force sensor 600 and the actual input standard load (force / torque), thus achieving accurate calibration of the six-dimensional force sensor 600.

[0059] Based on the above description, it is easy to understand that the six-dimensional force sensor static calibration device of this application embodiment, through the coordinated arrangement of the bearing platform 500, the first support component 100, the force beam 200, and multiple loading components 300, by providing at least one loading part 230 on the circumferential wall surface of each of the four orthogonally positioned extension arms 220 on the force beam 200, allows for the selection of a single loading component 300 to apply a standard load perpendicular to the wall surface to the loading part 230 on the corresponding wall surface of the corresponding extension arm 220. Through the force transmission action of the force beam 200, the device achieves unidirectional axial force along X / Y / Z and circumferential force on the six-dimensional force sensor 600. To apply a unidirectional torque along the X / Y / Z axes, two loading components 300 can be selected to simultaneously apply a standard load perpendicular to the wall surface to the loading portion 230 on the corresponding wall surface of the symmetrical extension arm 220. This allows for the synchronous loading of the positive and negative axial forces along the X / Y / Z axes and the synchronous loading of the positive and negative torques around the X / Y / Z axes of the six-dimensional force sensor 600. Alternatively, multiple loading components 300 can be selected to simultaneously apply a standard load perpendicular to the wall surface to the loading portion 230 on the corresponding wall surface of different extension arms 220, according to actual calibration requirements. This enables the simultaneous loading of forces and torques in multiple dimensions, effectively improving the calibration efficiency and accuracy of the six-dimensional force sensor 600.

[0060] In some embodiments of this application, see Figure 1 , Figure 3 , Figure 4 , Figure 7 and Figure 8 The six-dimensional force sensor static calibration device also includes four second support frames 400. The four second support frames 400 are vertically installed on the bearing platform 500 and located on the periphery of the first support component 100. The four second support frames 400 are arranged in a circular array about the Z-axis.

[0061] The loading assembly 300 includes a pulley block 310, a fixed boss 320, a pull rope 330, and a weight (not shown in the figure). The fixed boss 320 is located on the second support frame 400. At least one pulley 311 on the pulley block 310 is rotatably mounted on the fixed boss 320. The pull rope 330 is wound around the pulley 311 on the pulley block 310 and is detachably connected to the loading part 230. The free end of the pull rope 330 can be kept in a plumb bob state under the constraint of the pulley block 310 and the fixed boss 320. The weight is used to hang on the free end of the pull rope 330.

[0062] Specifically, the second support frame 400 can be a U-shaped plate vertically installed on the bearing platform 500, with the opening of the U-shaped plate facing the force beam 200 on the horizontal calibration plate 120. The fixed boss 320 is vertically installed on the second support frame 400, that is, the length direction of the fixed boss 320 is horizontal. The two opposite ends of the fixed boss 320 are respectively the near end fixed on the second support frame 400 and the far end away from the second support frame 400. The pulley block 310 includes one or more pulleys 311. One pulley 311 of the pulley block 310 is rotatably installed at the far end of the fixed boss 320. The end of the pull rope 330 is fixedly connected to the loading part 230 on the corresponding wall surface of the extension arm 220. The middle section of the pull rope 330 is horizontally inserted through the limiting groove on the top surface of the fixed boss 320. The free end of the pull rope 330 passes around the pulley 311 at the far end of the fixed boss 320 and is kept in a plumb state under the constraint of the pulley 311 and the limiting groove of the fixed boss 320. The loading part 230 can be a wire lock, which can lock or release the end of the pull rope 330. The pull rope 330 can be a steel wire rope with good structural strength and can withstand a large load.

[0063] The pulley block 310 may also include a pulley shaft (not shown in the figure), two deep groove ball bearings (not shown in the figure), and two pulley retaining rings (not shown in the figure). The opposite ends of the pulley shaft are rotatably mounted on the far end of the fixed boss 320 through the two deep groove ball bearings. The pulley 311 is keyed to the pulley shaft or connected by screws. The two pulley retaining rings are respectively located at the far end of the fixed boss 320 and on opposite sides of the pulley 311 in the axial direction. The two pulley retaining rings are used to limit the axial displacement of the pulley 311, prevent the pull rope 330 wrapped around the pulley 311 from deviating in the axial direction of the pulley 311, and further constrain the free end of the pull rope 330, so that the free end of the pull rope 330 remains in a stable plumb bob state.

[0064] Understandably, the end of the pull rope 330 of each loading component 300 is perpendicular to the wall of the extension arm 220 where the loading part 230 is located, and the cooperation of the pulley block 310 and the fixed boss 320 keeps the free end of the pull rope 330 in a stable plumb bob state.

[0065] When calibrating the six-dimensional force sensor 600, the operator can select the direction to apply a standard load to the six-dimensional force sensor 600 as needed, and hang a weight on the free end of the pull rope 330 of the corresponding loading component 300. The pull rope 330, in conjunction with the pulley group 310, transfers the weight's gravity to the end of the pull rope 330, so that the weight's gravity forms a standard load perpendicular to the corresponding wall surface of the extension arm 220, thereby achieving the loading of the six-dimensional force sensor 600.

[0066] In the above structure, because the ends of the pull ropes 330 of all loading components 300 are connected to the loading portions 230 on the wall of the corresponding extension arm 220, the free ends of the pull ropes 330 of all loading components 300 are kept in a plumb state under the constraint of the pulley block 310 and the fixed boss 320. This ensures that the pull ropes 330 of the loading components 300 do not generate a load on the corresponding loading portions 230 when no weight is attached. The operator only needs to selectively attach weights to the pull ropes 330 of one or more loading components 300, and increase or decrease the pull ropes 330. The number of weights on the 30 is sufficient to apply multi-directional and multi-dimensional forces / torques to the six-dimensional force sensor 600 without frequently adjusting or changing the connection position of the end of the pull rope 330, or frequently adjusting the direction of the pull rope 330 and the installation position of the pulley group 310. This not only reduces operational errors but also improves the loading efficiency of applying multi-directional and multi-dimensional forces / torques to the six-dimensional force sensor 600, meeting the requirements for constructing a sample data space for joint loading of six-dimensional forces, and correspondingly improving the calibration accuracy and precision of the six-dimensional force sensor 600.

[0067] In some embodiments of this application, see Figure 1 , Figure 3 , Figure 4 , Figure 7 and Figure 8 All the fixed bosses 320 on the loading components 300 extend in the horizontal direction, and at least three fixed bosses 320 on the loading components 300 are spaced apart along the height direction of the second support frame 400, and the length of all the fixed bosses 320 on each second support frame 400 decreases along the height direction of the second support frame 400.

[0068] It should be noted that in this application, the horizontal direction refers to the length or width direction of the bearing platform 500, which also corresponds to the direction parallel to the X-axis or the direction parallel to the Y-axis.

[0069] For example, the second support frame 400, which is directly opposite the extension arm 220 in the positive direction of the X-axis, has a fixing boss 320 extending in a direction that coincides with or is parallel to the X-axis. The extension directions of the fixing bosses 320 on the other second support frames 400 are similar and will not be described again.

[0070] On each second support frame 400, fixing bosses 320 with at least three loading components 300 are spaced apart along the height direction of the second support frame 400, and the length of all fixing bosses 320 on each second support frame 400 tends to decrease in the direction from bottom to top or from top to bottom.

[0071] The above structure extends the fixed boss 320 on the loading component 300 in the horizontal direction, so that the middle section of the pull rope 330 is in the horizontal direction under the constraint of the pulley 311 and the fixed boss 320. This facilitates the free end of the pull rope 330 to extend downward around the pulley 311 at the far end of the fixed boss 320 and maintain a stable plumb bob state, avoiding interference between the free end of the pull rope 330 and the pull ropes 330 of the other loading components 300.

[0072] By arranging the fixed protrusions 320 on at least three loading components 300 at intervals along the height direction of the second support frame 400, the three fixed protrusions 320 in the height direction correspond to the three walls of the extension arm 220 distributed along the height direction, which facilitates the staggered spatial arrangement of the pull ropes 330 of the loading components 300 in different directions.

[0073] By setting the length of all the fixed protrusions 320 on each second support frame 400 to decrease along the height direction of the second support frame 400, the vertical projections of the far ends of all the fixed protrusions 320 on the second support frame 400 are staggered, and the pulleys 311 installed at the far ends of the fixed protrusions 320 are spatially staggered, thereby completely staggering the corresponding three pull ropes 330 in space. This avoids the pull ropes 330 on different loading components 300 from intertwining and interfering with each other, thus improving the calibration accuracy and precision of the six-dimensional force sensor 600.

[0074] Further, see Figure 8 At least two opposing second support frames 400 are provided with three fixed bosses 320 spaced apart in the horizontal direction, and the load-bearing beam 200 is at the same height as the three fixed bosses 320 spaced apart in the horizontal direction.

[0075] Specifically, each of the two second support frames 400 that are opposite each other in the left-right direction is provided with three fixed bosses 320 that are spaced apart in the front-back direction.

[0076] With this configuration, the three fixed protrusions 320 on the second support frame 400, spaced apart in the horizontal direction, correspond to the three walls of the extension arm 220, which are also spaced apart in the horizontal direction. This allows the three fixed protrusions 320 to directly face the three walls of the extension arm 220, which are also spaced apart in the horizontal direction. The end of the pull rope 330 of the loading component 300 extends horizontally and connects to the loading part 230 of the corresponding wall of the extension arm 220 after passing over the pulley 311 at the far end of the fixed protrusions 320. Only one pulley 311 is needed to constrain the pull rope 330 to make one turn, reducing the transmission error of the gravity load of the weight to the loading part 230 along the pull rope 330, and further improving the calibration accuracy and precision of the six-dimensional force sensor 600.

[0077] In some embodiments of this application, see Figure 1 , Figure 3 , Figure 4 , Figure 7 , Figure 8 and Figure 9 The first support frame 110 includes two vertically positioned plates 111 arranged opposite each other and a horizontal bearing plate 112 connected between the two vertically positioned plates 111. A horizontal calibration plate 120 is connected between the two vertically positioned plates 111 and located below the horizontal bearing plate 112.

[0078] Thus, the two opposing vertical positioning plates 111 and the horizontal bearing plate 112 connecting the two vertical positioning plates 111 form a stable support structure, while creating a hollow space between the two opposing vertical positioning plates 111, providing clearance for the pull rope 330 of the corresponding loading component 300, and facilitating a stable connection between the pull rope 330 of the corresponding loading component 300 and the loading part 230 of the corresponding wall of the extension arm 220.

[0079] Further, see Figure 1 , Figure 3 , Figure 4 , Figure 7 , Figure 8 and Figure 9 In any loading component 300, when the position of the fixed boss 320 relative to the bearing platform 500 is higher than the position of the load-bearing beam 200 relative to the bearing platform 500, at least one pulley 311 on the pulley block 310 is rotatably disposed on the surface of the horizontal bearing plate 112 near the load-bearing beam 200. When the position of the fixed boss 320 relative to the bearing platform 500 is lower than the position of the load-bearing beam 200 relative to the bearing platform 500, at least one pulley 311 on the pulley block 310 is rotatably disposed on the surface of the horizontal calibration plate 120 away from the load-bearing beam 200.

[0080] It should be understood that in any loading component 300, when the position of the fixed boss 320 relative to the bearing platform 500 is higher than the position of the load-bearing beam 200 relative to the bearing platform 500, the pull rope 330 of the loading component 300 needs to be turned twice so that the end of the pull rope 330 is perpendicular to the corresponding wall surface of the extension arm 220.

[0081] Based on this, when the position of the fixed boss 320 relative to the bearing platform 500 is higher than the position of the load-bearing beam 200 relative to the bearing platform 500, the pulley block 310 includes two pulleys 311, one of which is rotatably mounted at the far end of the fixed boss 320, and the other of which is rotatably mounted on the surface of the horizontal bearing plate 112 near the load-bearing beam 200; when the position of the fixed boss 320 relative to the bearing platform 500 is lower than the position of the load-bearing beam 200 relative to the bearing platform 500, the pulley block 310 also includes two pulleys 311, one of which is rotatably mounted at the far end of the fixed boss 320, and the other of which is rotatably mounted on the surface of the horizontal calibration plate 120 away from the load-bearing beam 200.

[0082] This configuration serves two purposes. First, it ensures that the ends of the pull ropes 330 at different heights are perpendicular to the corresponding wall surfaces of the extension arm 220, reducing the transmission error of the weight's gravitational load along the pull ropes 330 to the loading section 230, and further improving the calibration accuracy of the six-dimensional force sensor 600. Second, by using the horizontal bearing plate 112 and the horizontal calibration plate 120 near the load-bearing beam 200 as mounting bases for one of the pulleys 311 on the pulley block 310, the installation layout of the pulleys 311 on the pulley block 310 is simplified, and the design length of the corresponding pull rope 330 is correspondingly shortened. This also ensures that the ends of the pull ropes 330 are directly aligned with the corresponding loading section 230, further reducing the transmission error of the weight's gravitational load.

[0083] Further, see Figure 1 and Figure 2 The horizontal calibration plate 120 has multiple first clearance holes 121 for the pull rope 330 to pass through, and the multiple first clearance holes 121 are arranged in a circular array about the Z-axis; the vertical positioning plate 111 has multiple second clearance holes 1111 for the pull rope 330 to pass through, and the multiple second clearance holes 1111 are distributed at intervals along the height direction.

[0084] Specifically, the first clearance hole 121 and the second clearance hole 1111 can be a strip hole, a round hole, a square hole, etc.

[0085] The multiple first clearance holes 121 on the horizontal calibration plate 120 are arranged in a circular array about the Z-axis, so that each first clearance hole 121 can directly face the loading part 230 of the corresponding wall surface of the extension arm 220, which is beneficial for the end of the pull rope 330 to pass through the first clearance hole 121 in the horizontal or vertical direction and form a stable connection with the loading part 230 of the corresponding wall surface of the extension arm 220.

[0086] The function of the second clearance hole 1111 on the vertical positioning plate 111 is the same, and will not be described again.

[0087] See Figure 3 , Figure 4 , Figure 7and Figure 8 The second support frame 400 has multiple weight reduction holes 410.

[0088] Specifically, the weight reduction hole 410 can be a strip-shaped hole.

[0089] The multiple weight-reducing holes 410 can reduce material consumption, lighten the weight of the second support frame 400, and facilitate the transfer and transportation of the second support frame 400.

[0090] See Figure 1 , Figure 4 , Figure 5 , Figure 6 , Figure 8 and Figure 9 A loading section 230 is provided at the center of the central section 211, and a loading component 300 applies a calibration load along the Z-axis to the loading section 230 at the center 211.

[0091] Specifically, at the center of the central part 210, which is also the center of gravity of the load-bearing beam 200, the loading component 300 applies a calibrated load to the loading part 230 at the center 211 along the Z-axis. The fixed boss 320 of the loading component 300 can be set on one of the second support frames 400. Of the two pulleys 311 of the pulley group 310 of the loading component 300, one pulley 311 is installed on the surface of the horizontal bearing plate 112 away from the load-bearing beam 200, and the other is installed at the far end of the corresponding fixed boss 320.

[0092] In this way, the six-dimensional force sensor 600 is subjected to axial force along the positive Z-axis and / or the Z-axis direction. Together with the other loading components 300, it further satisfies the requirement to construct a sample data space for joint loading of six-dimensional forces, and also improves the calibration accuracy and precision of the six-dimensional force sensor 600.

[0093] In addition, this application also provides a six-dimensional force sensor static calibration system, which includes the six-dimensional force sensor static calibration device of any of the above embodiments.

[0094] The six-dimensional force sensor static calibration system of this application embodiment may include a controller. By selecting one or more of the loading components 300, the loading components 300 apply a standard load perpendicular to the wall surface to the loading part 230 on the corresponding wall surface of different extension arms 220. This changes the magnitude and direction of the standard load applied to the six-dimensional force sensor 600, realizing independent loading and coupled loading of the six-dimensional force. The controller can output the corresponding channel signal according to the corresponding magnitude and direction when the six-dimensional force sensor 600 is subjected to the corresponding channel signal, establish the mapping relationship between the channel signal output by the six-dimensional force sensor 600 and the actual input standard load, and realize the accurate calibration of the six-dimensional force sensor 600.

[0095] The six-dimensional force sensor static calibration system of this application embodiment, due to the configuration of the aforementioned six-dimensional force sensor static calibration device, also has the same technical effect brought by the six-dimensional force sensor static calibration device. That is, according to the actual calibration requirements, multiple loading components 300 can be selected to simultaneously apply a standard load perpendicular to the wall surface to the loading part 230 on the corresponding wall surface of different extension arms 220, so as to realize the simultaneous loading of forces and torques in multiple dimensions, which can effectively improve the calibration efficiency and calibration accuracy of the six-dimensional force sensor 600.

[0096] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A static calibration device for a six-dimensional force sensor, characterized by The application relates to a six-dimensional force sensor, which comprises a bearing platform, a first support assembly, a force-bearing beam and a plurality of loading assemblies. The first support assembly comprises a first support frame vertically installed on the bearing platform and a horizontal calibration plate arranged on the first support frame, and the horizontal calibration plate is used for fixing a six-dimensional force sensor. The force-bearing beam is in a central-symmetrical cross-shaped structure and is parallel to the horizontal calibration plate, and the force-bearing beam comprises a central part connected to the six-dimensional force sensor and four extension arms connected to the central part, the axial direction of the central part is defined as the Z axis, the four extension arms are circumferentially arranged about the Z axis, at least one loading part is arranged on each wall surface of each extension arm along the circumferential direction of the extension arm, and the loading parts on two extension arms in the same axial direction are symmetrically distributed about the Z axis. The plurality of loading assemblies correspond to the plurality of loading parts one by one, and the loading assemblies are configured to apply calibration loads to the loading parts in a direction perpendicular to the corresponding wall surface of the extension arm. The application further comprises four second support frames vertically installed on the bearing platform and located at the periphery of the first support assembly, and the four second support frames are circumferentially arranged about the Z axis.

2. The six-axis force sensor static calibration device of claim 1, wherein, The loading assembly comprises a pulley block, a fixed boss, a pull rope and a weight, the fixed boss is arranged on the second support frame, at least one pulley on the pulley block is rotatably arranged on the fixed boss, the pull rope is arranged around the pulley on the pulley block and is detachably connected to the loading part, the free end of the pull rope can be kept in a plumb state under the constraint of the pulley block and the fixed boss, and the weight is used for being hung on the free end of the pull rope. The fixed bosses on all the loading assemblies extend in the horizontal direction, the fixed bosses on at least three loading assemblies are spaced apart in the height direction of the second support frame, and the lengths of all the fixed bosses on each second support frame decrease in the height direction of the second support frame.

3. The six-dimensional force sensor static calibration device of claim 2, wherein, Three fixed bosses spaced apart in the horizontal direction are arranged on at least two opposite second support frames, and the force-bearing beam is at the same height as the three fixed bosses spaced apart in the horizontal direction.

4. The six-axis force sensor static calibration device of claim 2, wherein, The first support frame comprises two oppositely arranged vertical positioning plates and a horizontal bearing plate connected between the two vertical positioning plates, the horizontal calibration plate is connected between the two vertical positioning plates and is located below the horizontal bearing plate.

5. The six-axis force sensor static calibration device of claim 2, wherein, In one loading assembly, when the position of the fixed boss relative to the bearing platform is higher than the position of the force-bearing beam relative to the bearing platform, at least one pulley on the pulley block is rotatably arranged on the surface of the horizontal bearing plate close to the force-bearing beam, and when the position of the fixed boss relative to the bearing platform is lower than the position of the force-bearing beam relative to the bearing platform, at least one pulley on the pulley block is rotatably arranged on the surface of the horizontal calibration plate away from the force-bearing beam.

6. The six-dimensional force sensor static calibration device of claim 5, wherein, A plurality of first avoiding holes for the pull rope to pass through are arranged on the horizontal calibration plate, and the plurality of first avoiding holes are circumferentially arranged about the Z axis; a plurality of second avoiding holes for the pull rope to pass through are arranged on the vertical positioning plate, and the plurality of second avoiding holes are spaced apart in the height direction.

7. The six-dimensional force sensor static calibration device of claim 6, wherein, ​ 8. The six-axis force sensor static calibration device of claim 5, wherein, A plurality of lightening holes are formed in the second support frame.

9. The six-dimensional force sensor static calibration device according to any one of claims 1 to 8, characterized in that, The center of the center part is provided with the loading part, and one of the loading assemblies applies a calibration load to the loading part at the center along the Z axis.

10. A six-dimensional force sensor static calibration system, characterized by, The six-dimensional force sensor static calibration device comprises the six-dimensional force sensor according to any one of claims 1 to 9.

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