CN114018472B - Swing arm for torque sensor calibration, calibration device, method and system - Google Patents

Abstract

The invention relates to a swing arm for calibrating a torque sensor, which comprises a fixed seat and at least one support arm, wherein the fixed seat is provided with a shaft hole, and the shaft hole is configured to be used for connecting a transmission shaft of the torque sensor; the fixing seat is also provided with a plurality of first mounting areas circumferentially arranged around the shaft hole, the first mounting areas are provided with first mounting directions, the first mounting directions are parallel to one radial direction of the shaft hole, and the first mounting areas are configured for mounting the level bubble along the first mounting directions; one end of the support arm is connected with the fixed seat and is perpendicular to the axis of the shaft hole, and the other end of the support arm is suspended and is configured to be used for connecting a load. The swing arm has reserved the first installation region of installation bubble to limited the first installation direction of first installation region, can form accurate angle definition for the installation of bubble, make the bubble install behind first installation region, can be according to the directional angle of first installation direction, supplementary angle to the swing arm is adjusted for the horizontality.

Description

Swing arm for torque sensor calibration, calibration device, method and system

Technical Field

The invention relates to the technical field of robots, in particular to a swing arm for calibrating a moment sensor, a moment sensor calibrating device, a moment sensor calibrating method, a moment sensor calibrating system and a moment sensor calibrating system.

Background

With the development of robot technology, a man-machine cooperation type mechanical arm is paid more attention to, and a robot joint is an important ring in the man-machine cooperation type mechanical arm, so that the operation precision of the mechanical arm is very important. Therefore, a moment sensor is arranged in the robot joint, the moment sensor can transmit moment on one hand, and can measure the moment value of the sensor on the other hand, the measured moment value of the sensor is compared with the theoretical moment, the difference between the measured moment value and the theoretical moment can be calculated, and the man-machine cooperation type mechanical arm is adjusted according to the difference, so that the man-machine cooperation type mechanical arm can accurately reach a preset position. Therefore, in order to make the robot-coordinated type mechanical arm operate accurately, calibration of the torque sensor in the robot joint becomes an important point.

At present, when the moment sensor is calibrated, the moment sensor is fixedly arranged on a bracket, a swing arm for assisting in measuring moment is arranged on a transmission shaft of the moment sensor, and whether the moment sensor needs to be calibrated or not can be judged by mounting test objects with different weights at the tail end of the swing arm, and calculating theoretical moment according to actual mounting conditions while utilizing the moment value of the sensor measured by the moment sensor and comparing the moment value of the sensor with the theoretical moment.

However, in such a torque sensor calibration method, when the angle of the swing arm to the horizontal plane is adjusted, the person skilled in the art mostly adjusts the angle of the swing arm by visual observation, which can certainly cause errors in the measurement result of the torque, and thus cause inaccuracy in the calibration result of the torque sensor.

Disclosure of Invention

Based on the above, it is necessary to provide a swing arm, a moment sensor calibration device, a method and a system for calibrating the moment sensor, and a robot calibration system for solving the problem of inaccurate calibration of the moment sensor.

The invention provides a swing arm for torque sensor calibration, comprising:

The fixed seat is provided with a shaft hole, and the shaft hole is configured to be used for connecting a transmission shaft of the torque sensor; the fixing seat is further provided with a plurality of first mounting areas circumferentially arranged around the shaft hole, the first mounting areas are provided with first mounting directions, the first mounting directions are parallel to one radial direction of the shaft hole, and the first mounting areas are configured for mounting the level bubble along the first mounting directions;

And one end of the support arm is connected with the fixed seat and is perpendicular to the axis of the shaft hole, and the other end of the support arm is suspended and is configured to be connected with a load.

In one embodiment, the included angle between the first installation direction of each first installation area and the same support arm is within a preset distribution included angle range; and/or the included angles of the first installation directions of the adjacent first installation areas are all within a preset interval included angle range.

In one embodiment, the included distribution angle ranges from 0 ° -360 °,0 ° -90 °, 90 ° -180 °, 180 ° -270 °, or 270 ° -360 °; and/or the interval included angle is in the range of 5-45 degrees.

In one embodiment, at least one of the support arms includes a reference arm, the distribution included angle ranges from 0 ° to 360 °, the number of the first installation areas is 36, the included angles between the first installation directions of adjacent first installation areas are all 10 °, and the included angle between the first installation direction of one of the first installation areas and the reference arm is 0 °;

Or at least one support arm comprises a reference arm, wherein the range of the distribution included angle is 0-90 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 0 degrees, 30 degrees, 45 degrees and 90 degrees respectively;

or at least one support arm comprises a reference arm, the range of the distribution included angle is 90 degrees to 180 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 90 degrees, 120 degrees, 135 degrees and 180 degrees respectively;

Or at least one support arm comprises a reference arm, the range of the distribution included angle is 180 degrees to 270 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 180 degrees, 210 degrees, 255 degrees and 270 degrees respectively;

Or at least one support arm comprises a reference arm, the distribution included angle ranges from 270 degrees to 360 degrees, the number of the first mounting areas is 4, and the included angles between the first mounting directions of the 4 first mounting areas and the reference arm are 270 degrees, 300 degrees, 315 degrees and 360 degrees respectively.

In one embodiment, the first mounting area is a mounting groove formed in the end face of the fixing base, and the mounting groove is configured to mount the vial along the first mounting direction;

or the first mounting area is an adhesion area arranged on the end face of the fixing seat, and the adhesion area is configured to adhere the level bubble along the first mounting direction;

or the first installation area is a magnetic attraction area arranged on the end face of the fixing seat, and the magnetic attraction area is configured to magnetically assemble the level bubble along the first installation direction.

In one embodiment, the number of the support arms is 2, the included angle of the 2 support arms is 180 °, at least one support arm is provided with at least one second mounting area, the second mounting area has a second mounting direction, the second mounting direction is parallel to the length direction of the support arm, and the second mounting area is configured to mount the vial along the second mounting direction.

In one embodiment, the second mounting region is located at an end of the suspension of the arm.

In one of the embodiments, a vial is mounted in at least one of said first mounting areas; and/or a vial is mounted in at least one of the second mounting areas.

In one embodiment, the support arm is provided with a plurality of hoisting parts along the length direction thereof, the distances between adjacent hoisting parts are equal, and the hoisting parts are configured to be used for connecting loads.

In one embodiment, the lifting part is a lifting hole formed in the support arm.

The invention also provides a moment sensor calibration device, which comprises:

A bracket configured for mounting a torque sensor to be calibrated;

the swing arm is provided with a shaft hole configured to be used for connecting with a transmission shaft of the moment sensor.

The invention also provides a moment sensor calibration method, which comprises the following steps of:

installing a moment sensor to be calibrated between the bracket and the swing arm;

Rotating the swing arm, rotating the swing arm to a preset target angle by means of a level bubble positioned in the first installation area, and connecting a load on the swing arm;

And acquiring a sensor moment value of the swing arm by using the moment sensor, calculating a theoretical moment value of the swing arm, and calculating a moment difference value between the sensor moment value and the theoretical moment.

In one embodiment, the method comprises the following steps:

step one: setting a plurality of target angles, and calculating the moment difference value under each target angle in sequence;

step two: when all the moment difference values are within a preset threshold value, finishing calibration;

step three: and when any moment difference value is not within a preset threshold value, overhauling the moment sensor, and repeating the first step and the second step.

The invention also provides a torque sensor calibration system, which comprises:

The moment sensor calibration device;

The processing unit is configured to obtain a sensor moment value of the swing arm, which is measured by the moment sensor, calculate a theoretical moment value of the swing arm, calculate a moment difference value between the sensor moment value and the theoretical moment, and compare the moment difference value with a preset threshold value to generate a calibration result.

In one embodiment, the processing unit includes:

A first processor configured to obtain a sensor moment value of the swing arm measured by the moment sensor;

A second processor configured to calculate a theoretical moment value of the swing arm;

And the third processor is configured to calculate a moment difference value between the sensor moment value and the theoretical moment and compare the moment difference value with a preset threshold value to generate a calibration result.

The invention also provides a robot calibration system, which is characterized by comprising:

the swing arm; or alternatively

The moment sensor calibration device; or alternatively

The torque sensor calibration system.

Above-mentioned a swing arm for torque sensor calibration has reserved the first installation region that is used for installing the bubble to first installation direction of first installation region has been limited, so, can form accurate angle definition for the installation of bubble, makes the bubble install behind first installation region, can be according to the directional angle of first installation direction, and supplementary adjusting the angle of swing arm for the horizontality, this can guarantee when the swing arm is used for correcting torque sensor, provides accurate swing arm rotation angle, and then guarantees that the correction result is accurate.

Drawings

FIG. 1 is a front view of a swing arm according to one embodiment of the invention;

FIG. 2 is a front view of a holder according to one embodiment of the present invention;

FIG. 3 is a schematic view of a first mounting area and a first mounting direction thereof according to an embodiment of the present invention;

FIG. 4 is a schematic view of a first mounting area and a first mounting direction thereof according to another embodiment of the present invention;

FIG. 5 is a schematic view of a second mounting area and a second mounting direction thereof according to an embodiment of the present invention;

FIG. 6 is a perspective view of a swing arm according to one embodiment of the invention;

FIG. 7 is a perspective view of a holder according to an embodiment of the present invention;

FIG. 8 is a perspective view of a holder with vials assembled in accordance with one embodiment of the present invention;

FIG. 9 is an enlarged view of a portion of the holder shown in FIG. 8;

FIG. 10 is a front view of a torque sensor calibration device according to one embodiment of the present invention;

FIG. 11 is a perspective view of a torque sensor calibration device according to one embodiment of the present invention;

fig. 12 is a schematic diagram of deflection theory of a swing arm according to an embodiment of the present invention.

Reference numerals:

100. swing arms; 200. a torque sensor; 300. a bracket;

110. A fixing seat; 120. a support arm; 130. a vial;

111. A shaft hole; 112. a first mounting area; 113. a first mounting direction;

121. a second mounting area; 122. a second mounting direction; 123. and (5) hoisting the part.

Detailed Description

In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the invention, whereby the invention is not limited to the specific embodiments disclosed below.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Referring to fig. 1 to 9, an embodiment of the present invention provides a swing arm 100 for calibrating a torque sensor 200, the swing arm 100 including: the torque sensor comprises a fixed seat 110 and at least one support arm 120, wherein the fixed seat 110 is provided with a shaft hole 111, and the shaft hole 111 is configured to be used for connecting a transmission shaft of the torque sensor 200; the fixing base 110 is further provided with a plurality of first mounting areas 112 circumferentially arranged around the shaft hole 111, the first mounting areas 112 have a first mounting direction 113, the first mounting direction 113 is parallel to one radial direction of the shaft hole 111, and the first mounting areas 112 are configured for mounting the vials 130 along the first mounting direction 113; one end of the support arm 120 is connected with the fixing seat 110 and is perpendicular to the axis of the shaft hole 111, the other end of the support arm 120 is suspended and configured to be used for connecting a load, the number of the support arms 120 can be one or more, when the support arms 120 are multiple, suitable angles can be adopted to mutually match and set, for example, the number of the support arms 120 is two, the two support arms 120 can be set to be in a state with an included angle according to requirements, and the included angle can be 180 degrees or any other angle.

The vials 130, also called vials 130, have different accuracies, the higher accuracy vials 130, and the measured results are more accurate. The bubble 130 has a scale, which can accurately reflect whether the rotation of the swing arm 100 reaches a desired rotation angle, and can obtain a plurality of relatively accurate rotation angle information of the swing arm 100 without any program control. The accuracy of the vial 130 refers to: the tilt angle of the vial 130 is such that the vial moves 2mm axially along the vial 130. The fixing base 110 may be square, circular, or irregular, and is not limited herein. The swing arm 100 not only can be used for quickly calibrating and measuring the internal torque sensor 200 at a specific angle by a robot joint, but also can be widely used for occasions with accurate requirements on specific angle positions. The relative relationship between the arm 120 and the fixing base 110 may be such that the arm 120 is perpendicular to or disposed at an angle to the axis of the shaft hole 111, which depends on the requirement for calibrating the torque sensor 200, and is not limited herein.

The swing arm 100 reserves a first installation area 112 for installing the vial 130, and defines a first installation direction 113 of the first installation area 112, so that an accurate angle definition can be formed for the installation of the vial 130, after the vial 130 is installed in the first installation area 112, the angle of the swing arm 100 relative to a horizontal state can be adjusted in an auxiliary manner according to the angle pointed by the first installation direction 113, which can ensure that the accurate rotation angle of the swing arm 100 is provided when the swing arm 100 is used for correcting the moment sensor 200, and further ensure that the correction result is accurate. The angle adjusting mode is simple, quick and direct, basically has no possibility of misoperation, and provides a high-precision angle judging method on the premise of ensuring low processing and using cost.

In addition, in order to facilitate the identification of the pointing angle of the first mounting direction 113 of each first mounting area 112, the fixing base 110 may further be provided with an angle marking device, and circumferentially surrounds the shaft hole 111, where the angle marking device is disposed, for example, concentrically with the first mounting direction 113. In some embodiments, the angle marking device is an angle dial, and the angle dial has a definite scale, so that the pointing angle of the first mounting direction 113 can be identified in an auxiliary manner, and the angle pointed by the level bubble 130 corresponding to the scale can be found on the angle dial.

In the arrangement of the first mounting regions 112, the first mounting regions 112 may be plural and can be used to mount a corresponding number of vials 130, but the specific number of vials 130 may be equal to or less than the number of first mounting regions 112, which is not limited herein. When the number of the first mounting areas 112 may be plural, the included angle between the first mounting direction 113 of each first mounting area 112 and the same arm 120 is within a preset range of distribution included angles, which determines the possible setting angle of the level bubble 130, and thus determines the angle to which the swing arm 100 can be adjusted, where the same arm 120 refers to a reference arm 120 used as a reference among one or more arms 120, and the first mounting directions 113 of the first mounting areas 112 may be set according to the included angle of the reference arm 120. Meanwhile, the angles of the first mounting directions 113 adjacent to the first mounting area 112 are all within a preset interval angle range, which determines the accuracy of the angle to which the swing arm 100 can be adjusted.

In one embodiment, the included distribution angle ranges from 0 ° to 360 °, 0 ° to 90 °, 90 ° to 180 °, 180 ° to 270 °, or 270 ° to 360 °. The interval included angle range is 5-45 degrees, and the distribution included angle range and the interval included angle range can be other range values.

In one embodiment, at least one of the arms 120 includes a reference arm 120, the distribution included angle ranges from 0 ° to 360 °, the number of the first mounting areas 112 is 36, the included angles between the first mounting directions 113 of adjacent first mounting areas 112 are all 10 °, and the included angle between the first mounting direction 113 of one of the first mounting areas and the reference arm 120 is 0 °, at this time, the swing arm 100 may adjust 36 angles with an accuracy of every 10 °, and the moment sensor 200 is calibrated with the accuracy.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution included angle ranges from 0 ° to 90 °, the number of the first mounting areas 112 is 4, and the included angles between the first mounting directions 113 of the 4 first mounting areas 112 and the reference arm 120 are respectively 0 °, 30 °, 45 ° and 90 °, if the reference arm 120 refers to the left arm 120 in fig. 1, the vial 130 may be disposed at a position within 90 ° around the upper left corner of the shaft hole 111, and the swing arm 100 is rotated to an angle of 0 °, 30 °, 45 ° and 90 ° with respect to the horizontal state.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution included angle ranges from 90 ° to 180 °, the number of the first mounting areas 112 is 4, and the included angles between the first mounting directions 113 of the 4 first mounting areas 112 and the reference arm 120 are 90 °, 120 °, 135 ° and 180 °, respectively, if the reference arm 120 refers to the arm 120 on the left side in fig. 1, the position where the vial 130 may be disposed is within the range of 90 ° around the upper right corner of the shaft hole 111, and the swing arm 100 is rotated to the included angles of 90 °, 120 °, 135 ° and 180 ° with respect to the horizontal state.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle ranges from 180 ° to 270 °, the number of the first mounting areas 112 is 4, and the first mounting directions 113 of the 4 first mounting areas 112 and the reference arm 120 have angles of 180 °, 210 °, 255 ° and 270 °, respectively, if the reference arm 120 refers to the left arm 120 in fig. 1, the vial 130 may be disposed at a position within 90 ° around the lower right corner of the shaft hole 111, and the swing arm 100 is rotated to angles of 180 °, 210 °, 255 ° and 270 ° with respect to the horizontal state.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle ranges from 270 ° to 360 °, the number of the first mounting areas 112 is 4, and the first mounting directions 113 of the 4 first mounting areas 112 and the reference arm 120 respectively have angles of 270 °, 300 °, 315 ° and 360 °, if the reference arm 120 refers to the left arm 120 in fig. 1, the vial 130 may be disposed at a position within 90 ° around the lower left corner of the shaft hole 111, and the swing arm 100 is rotated to angles of 270 °, 300 °, 315 ° and 360 ° with respect to the horizontal state.

After the first mounting area 112 is disposed in different directions about the shaft hole 111 (e.g., upper left, upper right, lower left, lower right, as previously described), the vial 130 may be allowed to be mounted in different directions about the shaft hole 111, which may facilitate replacement of the first mounting area 112 and the vial 130 in different directions, extend life, and rotate the swing arm 100 clockwise or counterclockwise to a desired angle, as desired.

However, the above angle ranges are only provided as some embodiments, and those skilled in the art may also set the number of the first mounting areas 112 and the spacing included angle according to actual needs, so as to meet the specific calibration requirement of the torque sensor 200, which is not limited herein.

As for the specific form of the first mounting area 112, the first mounting area 112 is a mounting groove formed on an end surface of the fixing base 110, and the mounting groove is configured to mount the vial 130 along the first mounting direction 113. The first mounting region 112 may also be an adhesive region provided on the end face of the holder 110, which is configured for adhering the vial 130 in the first mounting direction 113. The first mounting region 112 may also be a magnetic attraction zone disposed on an end surface of the fixing base 110, where the magnetic attraction zone is configured to magnetically assemble the vial 130 along the first mounting direction 113. In addition, the first mounting area 112 may be a bayonet connection, a screw connection, or any other corresponding connection method, which is not limited herein.

Referring to fig. 7 to 9, corresponding mounting grooves are formed in the swing arm 100 at desired angular positions, the position accuracy and the dimensional accuracy of the mounting grooves can be very high (0.01 mm accuracy level) by machining, the mounting grooves are formed, and then the leveling bubble 130 is mounted in the mounting grooves, so that the operation is convenient, the angular positions of part of the mounting grooves are shown in fig. 1, in addition, the mounting grooves can be subdivided as required, the flexibility of the mounting positions is very high, and the mounting grooves can be formed in any places with space.

In one embodiment, the number of the support arms 120 is 2, the included angle of 2 support arms 120 is 180 °, at least one second mounting area 121 is disposed on at least one support arm 120, the second mounting area 121 has a second mounting direction 122, the second mounting direction 122 is parallel to the length direction of the support arm 120, and the second mounting area 121 is configured to mount the vial 130 along the second mounting direction 122. At this time, the second mounting region 121 provides a position where the vial 130 can be mounted on the arm 120 in addition to the first mounting region 112, and the second mounting region 121 and the second mounting direction 122 may be the same as or different from the first mounting region 112 and the first mounting direction 113, so reference may be made to the technical contents of the first mounting region 112 and the first mounting direction 113, and the same contents will not be repeated.

The second mounting area 121 serves as a structure for mounting the vial 130, and the second mounting area 121 may be disposed at any position of the swing arm 100, for example, the second mounting area 121 is located at one end of the suspension of the arm 120, or the second mounting area 121 is located at a central position between both ends of the arm 120.

The first mounting region 112 and the second mounting region 121 are provided as structures for mounting the vials 130, which do not limit whether or not the vials 130 are actually mounted, but provide a possibility of being able to mount the vials 130. In actual use, the number and positions of the vials 130 may be selected according to the requirements, the vials 130 may be mounted in at least one of the first mounting areas 112, or the vials 130 may be mounted in all of the first mounting areas 112, or the vials 130 may be mounted in at least one of the second mounting areas 121, or the vials 130 may be mounted in all of the second mounting areas 121. For example, only a single vial 130 may be used to switch between different first 112 and second 121 mounting regions.

Furthermore, since the first mounting area 112 or the second mounting area 121 is a slotted mounting groove structure, the mounting groove is not limited to the surface of the fixing base 110 or the support arm 120, for example, the mounting groove may be formed in the fixing base 110 or the support arm 120, so long as the mounting groove can allow the vial 130 to be mounted and dismounted in the mounting groove, and the corresponding portion of the fixing base 110 or the support arm 120 corresponding to the mounting groove may also be formed into a transparent structure to realize reading of the vial 130.

Meanwhile, the specific shape of the first mounting region 112 or the second mounting region 121 may be set correspondingly according to the shape of the vial 130 to be mounted, and is not limited to a regular or irregular shape including a rectangle, a square, etc., as long as the vial 130 can be mounted stably and in a precise direction.

When the vials 130 are mounted on both the arms 120, the vials 130 on both the arms 120 can be used for calibrating each other, and the deformation of the swing arm 100 after the load is mounted can be observed, so as to calculate values of deflection, rigidity, etc.

For the above mentioned calculation of deflection and stiffness, the calculation method is as follows:

the swing arm 100 is simplified into a model as shown in fig. 12, the solid line in fig. 12 is the initial position of the swing arm 100, the broken line in fig. 12 is the position where the swing arm 100 is deformed under force, the deformation y is the deflection of the swing arm 100, and the stiffness k is defined as the moment required to be applied to generate the deformation per radian.

The deflection y value can be calculated from the readings of the vial 130 and based on the formula, assuming that the level of accuracy of this vial 130 is a (in/2 mm, i.e., the angle corresponding to each 2mm of movement of the bubble), the dashed line in FIG. 12 indicates the reading of the vial 130 as x (in mm).

At this time, the suspension end of the swing arm 100 deforms to a deflection

Rigidity is as followsk＝mg/y，

When the stiffness of the swing arm 100 is very high (far beyond the stiffness of the harmonic reducer), the measured stiffness k may be considered the stiffness of the harmonic reducer, and when the swing arm 100 is very low (far below the stiffness of the harmonic reducer), the measured stiffness k may be considered the stiffness of the swing arm 100 itself.

In one embodiment, the arm 120 is provided with a plurality of lifting parts 123 along the length direction thereof, the distances between adjacent lifting parts 123 are equal, and the lifting parts 123 are configured to be used for connecting a load. For example, the arm 120 may be 0.6m-1.2m, such as 0.6m, 0.7m, 0.8m, 0.9m, 1m, 1.1m, 1.2m, etc., and then the distances between the adjacent hoisting portions 123 are equal, so that the actual distance between the load and the fixing base 110 when the load is hoisted to a certain hoisting portion 123 can be calculated, and the distance is also the length of the actual arm. The lifting portion 123 may be a lifting hole formed on the support arm 120, or may be an alternative structure that can implement load connection, such as a fastening structure, a threaded connection structure, etc., which is not limited herein.

Referring to fig. 10 and 11, the present invention further provides a torque sensor 200 calibration device, including a bracket 300 and a swing arm 100, wherein the bracket 300 is configured to mount a torque sensor 200 to be calibrated, and the shaft hole 111 of the swing arm 100 is configured to connect with a transmission shaft of the torque sensor 200. The torque sensor 200 may include a fixed end and a movable end, when the torque sensor 200 needs to be calibrated, the fixed end of the torque sensor 200 may be fixedly connected to the bracket 300, the movable end of the torque sensor 200 may include a transmission shaft, the transmission shaft may rotate relative to the torque sensor 200, and the swing arm 100 is installed on the transmission shaft of the torque sensor 200 and is assembled with the transmission shaft through the shaft hole 111. At this time, according to the calibration requirement, a desired vial 130 may be installed by means of the first installation region 112, and the angle of the swing arm 100 may be adjusted by means of the vial 130, thereby performing the calibration of the torque sensor 200. Since the specific structure, functional principle and technical effects of the swing arm 100 are described in detail above, they will not be described in detail herein. Any technical content related to the swing arm 100 can be referred to as the foregoing description.

The invention also provides a method for calibrating the moment sensor 200, which uses the device for calibrating the moment sensor 200, and comprises the following steps: mounting a torque sensor 200 to be calibrated between the bracket 300 and the swing arm 100; rotating the swing arm 100, rotating the swing arm 100 to a preset target angle by means of the level bubble 130 positioned in the first mounting area 112, and connecting a load on the swing arm 100; and acquiring a sensor moment value of the swing arm 100 by using the moment sensor 200, calculating a theoretical moment value of the swing arm 100, and calculating a moment difference value between the sensor moment value and the theoretical moment. After the moment difference is obtained, the moment difference can be conveniently compared with a threshold value, and if the moment difference is not within the threshold value, the moment difference indicates that the moment measuring function of the moment sensor 200 has defects and needs to be overhauled. The threshold represents the degree of stability of the operating state of the torque sensor 200, and may be defined according to the requirement.

In the detailed calibration method, the torque sensor 200 calibration method further includes the steps of: step one: setting a plurality of target angles, and calculating the moment difference value under each target angle in sequence; step two: when all the moment difference values are within a preset threshold value, finishing calibration; step three: and when any moment difference value is not within a preset threshold value, overhauling the moment sensor 200, and repeating the first step and the second step.

According to the first and second steps, if the moment difference value after comparison is within the threshold value, the moment sensor 200 is in a qualified state at this time, but once the moment difference value measured by the swing arm 100 at any angle is not within the threshold value, at least the working state of the moment sensor 200 at the angle is proved to be a non-qualified state, so that maintenance is required to be performed, and the moment sensor 200 is ensured to have a relatively stable working state. After maintenance, recalibration is performed until the torque sensor 200 is in a proper state at a predetermined plurality of target angles. The overhauling moment sensor 200 is understood to be a reworking moment sensor 200, such as a reloading component, a re-debugging, etc., so that a defect of the force sensor is repaired.

It should be noted that the calibration method is suitable for manual calibration or automatic control calibration.

The invention also provides a torque sensor 200 calibration system, which comprises the torque sensor 200 calibration device and a processing unit, wherein the processing unit is configured to acquire a sensor torque value of the swing arm 100 measured by the torque sensor 200, calculate a theoretical torque value of the swing arm 100, calculate a torque difference value between the sensor torque value and the theoretical torque, and compare the torque difference value with a preset threshold value to generate a calibration result. At this time, according to the logic judgment, the processing unit may be used to automatically control the calibration until the moment difference is compared with the preset threshold value to obtain an intuitive calibration result, where the calibration result may at least include a qualified or unqualified result, or may further provide, according to the setting of the threshold value, subdivision results such as a preferred state, a suboptimal state, and a poor state of the moment sensor 200, so as to embody the intellectualization of the automatic control calibration, which is not limited herein.

In one embodiment, the processing unit includes a first processor, a second processor, and a third processor, where the first processor is configured to obtain a sensor moment value of the swing arm 100 measured by the moment sensor 200; the second processor is configured to calculate a theoretical moment value of the swing arm 100; the third processor is configured to calculate a torque difference between the sensor torque value and the theoretical torque, and compare the torque difference with a preset threshold value to generate a calibration result. The first processor, the second processor and the third processor may optionally adopt a wired or wireless data transmission mode according to requirements, which is not limited herein. Meanwhile, a matched interaction unit can be arranged, and the interaction unit can be a display and other devices and is used for displaying data, prompt information, calibration results and other necessary information in the calibration process.

The invention also provides a robot calibration system comprising the swing arm 100; or the torque sensor 200 calibration means; or the torque sensor 200 calibrates the system. Since the specific structure, functional principle and technical effects of the swing arm 100, the torque sensor 200 calibration device and the torque sensor 200 calibration system are described in detail above, the detailed description thereof will be omitted. Any technical content related to the swing arm 100, the torque sensor 200 calibration device, and the torque sensor 200 calibration system can be referred to in the foregoing description.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims (14)

1. A swing arm for torque sensor calibration, the swing arm comprising:

The fixed seat is provided with a shaft hole, and the shaft hole is configured to be used for connecting a transmission shaft of the torque sensor; the fixing seat is further provided with a plurality of first mounting areas circumferentially arranged around the shaft hole, the first mounting areas are provided with first mounting directions, the first mounting directions are parallel to one radial direction of the shaft hole, and the first mounting areas are configured for mounting the level bubble along the first mounting directions;

The other end of the support arm is suspended and is configured to be used for connecting a load;

The first mounting area is a mounting groove formed in the end face of the fixing seat, and the mounting groove is configured to be used for mounting the level bubble along the first mounting direction; or the first mounting area is an adhesion area arranged on the end face of the fixing seat, and the adhesion area is configured to adhere the level bubble along the first mounting direction; or the first installation area is a magnetic attraction area arranged on the end face of the fixed seat, and the magnetic attraction area is configured to magnetically assemble the level bubble along the first installation direction;

The number of the support arms is 2, the included angle of the 2 support arms is 180 degrees, at least one support arm is provided with at least one second installation area, the second installation area is provided with a second installation direction, the second installation direction is parallel to the length direction of the support arms, and the second installation area is configured to be used for installing the level bubble along the second installation direction.

2. The swing arm of claim 1, wherein the first mounting direction of each of said first mounting areas is within a predetermined range of distributed angles from the same arm; and/or the included angles of the first installation directions of the adjacent first installation areas are all within a preset interval included angle range.

3. The swing arm of claim 2, wherein said included distribution angle ranges from 0 ° -360 °,0 ° -90 °, 90 ° -180 °, 180 ° -270 °, or 270 ° -360 °; and/or the interval included angle is in the range of 5-45 degrees.

4. A swing arm according to claim 3 wherein at least one of said arms includes a reference arm, said included angle being in the range of 0 ° to 360 °, said number of first mounting areas being 36, said first mounting directions adjacent said first mounting areas each having an included angle of 10 °, wherein said first mounting direction of one of said first mounting areas has an included angle of 0 ° with said reference arm;

Or at least one support arm comprises a reference arm, wherein the range of the distribution included angle is 0-90 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 0 degrees, 30 degrees, 45 degrees and 90 degrees respectively;

or at least one support arm comprises a reference arm, the range of the distribution included angle is 90 degrees to 180 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 90 degrees, 120 degrees, 135 degrees and 180 degrees respectively;

Or at least one support arm comprises a reference arm, the range of the distribution included angle is 180 degrees to 270 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference arm are 180 degrees, 210 degrees, 255 degrees and 270 degrees respectively;

Or at least one support arm comprises a reference arm, the distribution included angle ranges from 270 degrees to 360 degrees, the number of the first mounting areas is 4, and the included angles between the first mounting directions of the 4 first mounting areas and the reference arm are 270 degrees, 300 degrees, 315 degrees and 360 degrees respectively.

5. The swing arm of claim 1 wherein said second mounting area is located at an end of the suspension of said arm.

6. The swing arm of claim 1 wherein a vial is mounted in at least one of said first mounting areas; and/or a vial is mounted in at least one of the second mounting areas.

7. The swing arm of claim 1, wherein a plurality of hanging parts are formed on the support arm along a length direction thereof, and a distance between adjacent hanging parts is equal, and the hanging parts are configured to be used for connecting a load.

8. The swing arm of claim 7, wherein said hanging portion is a hanging hole formed in said arm.

9. A torque sensor calibration device, comprising:

A bracket configured for mounting a torque sensor to be calibrated;

The swing arm of any one of claims 1-8, the shaft aperture of the swing arm configured as a drive shaft for connecting the torque sensor.

10. A torque sensor calibration method, characterized by using the torque sensor calibration device according to claim 9, comprising the steps of:

installing a moment sensor to be calibrated between the bracket and the swing arm;

Rotating the swing arm, rotating the swing arm to a preset target angle by means of a level bubble positioned in the first installation area, and connecting a load on the swing arm;

And acquiring a sensor moment value of the swing arm by using the moment sensor, calculating a theoretical moment value of the swing arm, and calculating a moment difference value between the sensor moment value and the theoretical moment.

11. The method of calibrating a torque sensor according to claim 10, comprising the steps of:

step one: setting a plurality of target angles, and calculating the moment difference value under each target angle in sequence;

step two: when all the moment difference values are within a preset threshold value, finishing calibration;

step three: and when any moment difference value is not within a preset threshold value, overhauling the moment sensor, and repeating the first step and the second step.

12. A torque sensor calibration system, comprising:

The torque sensor calibration device of claim 9;

The processing unit is configured to obtain a sensor moment value of the swing arm, which is measured by the moment sensor, calculate a theoretical moment value of the swing arm, calculate a moment difference value between the sensor moment value and the theoretical moment, and compare the moment difference value with a preset threshold value to generate a calibration result.

13. The torque sensor calibration system of claim 12, wherein the processing unit comprises:

A first processor configured to obtain a sensor moment value of the swing arm measured by the moment sensor;

A second processor configured to calculate a theoretical moment value of the swing arm;

And the third processor is configured to calculate a moment difference value between the sensor moment value and the theoretical moment and compare the moment difference value with a preset threshold value to generate a calibration result.

14. A robotic calibration system, comprising:

A swing arm as claimed in any one of claims 1 to 8; or alternatively

The torque sensor calibration apparatus of claim 9; or alternatively

A torque sensor calibration system as claimed in claim 12 or 13.