A joint torque sensor and robot joint
By designing a joint torque sensor including inner ring, outer ring, measuring beam and support beam, the problems of large size and low accuracy of torque sensors in the prior art are solved, and a three-dimensional torque sensor with compact structure and high accuracy are realized. Application in complex scenarios of industrial robot joints.
Patent Information
- Application Number
- CN202110124625.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-01-29
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2041-01-29
AI Technical Summary
The torque sensors of existing industrial robot joints have a single structure, large volume and weight, and low accuracy, making it difficult to meet the requirements of small size, high accuracy and compact structure.
Design a joint torque sensor including inner ring, outer ring, measuring beam and support beam. By reasonably distributing and adjusting the size of support beam and measuring beam, a three-dimensional torque sensor with high accuracy and good rigidity can be realized, which can detect bending moment and torque. , and replaces traditional output flanges to provide overload protection.
It realizes a joint torque sensor with compact structure and high accuracy, which can accurately detect joint torque information, improve the motion control accuracy and stiffness of robot joints, and is suitable for industrial applications in complex scenarios.
Smart Images
Figure CN114905483B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of industrial robots, and in particular to a joint torque sensor and a robot joint. Background Art
[0002] Industrial robots are a type of robot widely used in industrial environments. Industrial robots can generally be divided into traditional industrial robots and new collaborative robots. Compared with traditional industrial robots, new collaborative robots have the advantages of light weight, small size, and good usability. Therefore, they are suitable for application in more scenarios, such as industry, service industry, catering industry, etc.
[0003] Industrial robots can perform work tasks by connecting to the end effector. Before the robot performs the work task, it needs to be taught and guided. The teaching methods of robots can generally be divided into direct teaching and traditional teaching methods. The traditional teaching method mainly relies on the teaching pendant. This teaching method has low working efficiency, cumbersome and non-intuitive process, and requires a high level of knowledge from the operator. In contrast, the direct teaching method is more intuitive and greatly reduces the requirements for the operator. Zero force control is the key technology to realize the direct teaching control scheme. Its core is to convert the magnitude and direction of the external force into the corresponding position instruction. There are generally two ways to detect external force, one is to use current feedback, and the other is to use torque sensor detection. Compared with the current detection method, the torque sensor does not need to estimate the joint torque, and can directly measure the real-time output torque of each joint, which directly avoids the difficulty of dynamic modeling parameter identification and avoids the introduction of noise interference and time delay in the dynamic equation. At the same time, the torque sensor is also very suitable for complex assembly operations based on torque detection and contact human-machine collaborative operation industries such as the medical industry. Joint torque sensors can accurately control the torque of each joint of the robot. Installing torque sensors on the joints of the robot to collaboratively complete tasks in complex scenarios is an inevitable trend to achieve human-machine integration.
[0004] At present, some manufacturers in the field of industrial robots have begun to apply torque sensors to robot joints. However, traditional torque sensors have a simple structure, large size and weight, and low precision. In the current scenario where industrial robots are generally modularly designed, it is difficult for them to meet the requirements of small size, high precision, and compact structure.
[0005] Therefore, it is necessary to design a joint torque sensor and robot joint with compact structure and high precision. Summary of the invention
[0006] In view of this, an object of the present invention is to provide a joint torque sensor and a robot joint with compact structure and high precision.
[0007] The present invention can adopt the following technical solution: a joint torque sensor, comprising an inner ring, an outer ring, and at least two measuring beams and at least two supporting beams connecting the inner ring and the outer ring, the measuring beams being pasted with strain gauges, one of the inner ring and the outer ring being an input connecting flange, and the other being an output connecting flange, the number of the supporting beams being greater than or equal to the number of the measuring beams, and at least one supporting beam being arranged between adjacent measuring beams.
[0008] Furthermore, along the axial direction of the joint torque sensor, the height of the support beam is greater than the height of the measuring beam.
[0009] Furthermore, the torque sensor is a three-dimensional torque sensor, and the torque sensor is used to detect bending moment and torque.
[0010] Furthermore, the torque sensor is used to calibrate the torque at least partially according to the bending moment, and output the torque calibrated according to the bending moment.
[0011] Furthermore, a groove is provided at a position of the outer ring corresponding to the connection position of the measuring beam, and the groove is provided along the outer edge of the outer ring.
[0012] Furthermore, along the axial direction of the joint torque sensor, the upper and lower surfaces of the measuring beam form a depression relative to the inner ring.
[0013] Furthermore, the torque sensor includes an overload protection beam extending from the outer ring to the inner ring, and a gap is formed between the overload protection beam and the inner ring.
[0014] Furthermore, the measuring beam is formed as a plate-shaped beam, and the plate-shaped beam is arranged parallel to the horizontal plane.
[0015] Furthermore, the at least two measuring beams are symmetrical with respect to the center of the joint torque sensor, and shear strain gauges are symmetrically pasted on the upper and lower surfaces of the measuring beams. The strain gauges pasted on the at least two measuring beams are symmetrical with respect to the center of the joint torque sensor.
[0016] Furthermore, the support beam is formed as a plate-shaped beam, the measuring beam is formed as a plate-shaped beam, and the support beam and the measuring beam are perpendicular.
[0017] Furthermore, the inner ring includes a plurality of locking holes distributed circumferentially along the outer edge, and the overload protection beam is arranged between adjacent locking holes and forms gaps with the adjacent locking holes respectively.
[0018] Furthermore, the outer ring includes a connecting hole extending in the radial direction, and the connecting hole is formed at a corresponding position of the outer ring where the overload protection beam is arranged.
[0019] The present invention can also adopt the following technical solution: a robot joint, comprising a housing, a motor, a reducer, and a joint torque sensor as described above, wherein the input connecting flange is connected to the output end of the reducer, and the output connecting flange is used to connect to the housing of another joint of the robot to transmit the force / torque at the output end of the reducer to the other joint.
[0020] Compared with the prior art, the beneficial effects of the specific embodiments of the present invention are as follows: the joint torque sensor includes an input connecting flange and an output connecting flange, and the joint torque sensor can be used as the output flange of the joint. At the same time, by reasonably distributing the support beam and the measuring beam and adjusting the size settings of the two, the stiffness is better while maintaining the accuracy of the joint torque sensor. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The above-mentioned objectives, technical solutions and beneficial effects of the present invention can be achieved through the following drawings:
[0022] Figure 1 Schematic diagram of a joint torque sensor according to an embodiment of the present invention
[0023] Figure 2 yes Figure 1 Schematic diagram of the tilt of the joint torque sensor shown in the embodiment
[0024] Figure 3 Schematic diagram of a joint torque sensor according to another embodiment of the present invention
[0025] Figure 4 yes Figure 3 Schematic diagram of the joint torque sensor of the embodiment with a strain gauge attached
[0026] Figure 5 Schematic diagram of a robot joint according to an embodiment of the present invention DETAILED DESCRIPTION
[0027] In order to make the purpose, technical scheme and advantages of the present invention clearer, the scheme in the embodiment of the present invention will be described clearly and completely in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention but not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0028] Among them, the terms "upper", "lower", "left", "right", etc. are used to describe the relative position relationship of each structure in the accompanying drawings, which is only for the convenience of description and is not intended to limit the scope of implementation of the present invention. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of the present invention without substantially changing the technical content.
[0029] The present invention protects a joint torque sensor, Figure 1-Figure 2 , Figure 1 A schematic diagram of a joint torque sensor 100 according to an embodiment of the present invention is given as an example. The joint torque sensor 100 includes an inner ring 1, an outer ring 2, and at least two measuring beams 3 and at least two supporting beams 4 connecting the inner ring 1 and the outer ring 2. The measuring beam 3 is pasted with a strain gauge. One of the inner ring 1 and the outer ring 2 is an input connecting flange, and the other is an output connecting flange. The number of the supporting beams 4 is greater than or equal to the number of the measuring beams 3, and at least one supporting beam 4 is provided between adjacent measuring beams 3. Preferably, the inner ring 1 is an input connecting flange, and the outer ring 2 is an output connecting flange. The input connecting flange can receive force / torque and transmit it to the next joint through the output flange connecting flange. Specifically, the robot joint is connected to the joint torque sensor 100, which can accurately detect the torque output of the joint so that the robot can face various complex usage scenarios and accurately control the movement of the robot. The power of the robot joint is transmitted by the output flange. In the traditional technology, the joint is installed with the output flange and the torque sensor 100 at the same time to obtain the torque output of the joint, but this requires the joint to have a larger installation space to meet the installation requirements of the torque sensor 100. In the prior art, some robots, especially collaborative robots, require a more compact structure, and some scenes cannot meet the requirements of installing the output flange and the torque sensor at the same time. The distance between the output end of the reducer and the joint housing is small, which poses a greater challenge to the design of the torque sensor. The joint torque sensor provided by the present invention can only replace the output flange with the joint torque sensor 100. The joint torque sensor 100 can not only detect the joint torque information, but also provide the function of the original output flange. It has a compact structure and does not need to redesign the body structure of the robot. On the other hand, the joint torque sensor 100 includes a support beam and a measuring beam, the measuring beam 3 can be deformed by force to detect torque, the support beam 4 provides support for the joint torque sensor 100, and the joint torque sensor 100 includes at least two support beams 4, and the number of support beams 4 is at least equal to the number of measuring beams 3, and support beams 4 are arranged between adjacent measuring beams 3 to ensure the rigidity of the joint torque sensor 100. The above-mentioned joint torque sensor 100 realizes the two-in-one function of the joint output flange and the torque sensor 100, and the structure is relatively compact. At the same time, the design of the support beam 4 makes the rigidity of the joint torque sensor 100 better.
[0030] The joint torque sensor 100 includes a support beam 4 and a measuring beam 3. The measuring beam 3 is used to deform under force to detect torque information, while the support beam 4 is mainly used to make the joint torque sensor 100 have suitable rigidity. For the measuring beam 3, in order to ensure the detection sensitivity of the joint torque sensor 100, its rigidity needs to be appropriately sacrificed, and the joint torque sensor 100 is also used as an output flange, so its rigidity also needs to be reasonable. On the one hand, by setting the number of support beams 4 to be greater than or equal to the number of measuring beams 3, and at least one support beam 4 is provided between adjacent measuring beams 3, the distribution of the support beams 4 can meet the rigidity requirements of the joint torque sensor 100 as much as possible; on the other hand, the support beam 4 and the measuring beam 3 are of different sizes, so that the rigidity of the support beam 4 meets the requirements of the joint torque sensor 100 as much as possible. Specifically, a coordinate system is established with the center of the joint torque sensor 100 as the coordinate origin, the axial direction of the joint torque sensor 100 is the Z-axis direction, and the corresponding directions perpendicular to the Z-axis direction are the X-axis and Y-axis directions. The joint torque sensor 100 is used to output torque information, that is, the detection information of Mz. Appropriately reducing the height of the measuring beam 3 is conducive to increasing the sensitivity of the measuring beam 3. The height of the support beam 4 is greater than the height of the measuring beam 3, so that the rigidity of the support beam 4 is better at least in the Mx and My directions. That is, the sizes of the support beam 4 and the measuring beam 3 are different so that the rigidity of the support beam 4 is better at least in the Mx and My directions. Specifically, the height of the support beam 4 is greater than the height of the measuring beam.
[0031] In one embodiment of the present invention, the joint torque sensor 100 is a three-dimensional torque sensor 100, and the torque sensor 100 is used to detect bending moment and torque. Further, the torque sensor 100 is used to detect the joint output torque and the bending moment borne by the joint, that is, the torque sensor 100 is used to detect Mx, My, and Mz. The joint torque sensor can replace the output flange of the joint, can detect the bending moment borne by the joint, and confirm the deformation of the joint to obtain a higher-precision joint robot position output. Further, the joint torque sensor 100 in the present invention replaces the original joint output flange. The joint torque sensor 100, like the traditional joint output flange, can at least withstand the torques of Mx, My, and Mz, while the torque sensor installed on the joint in the prior art does not directly contact the joint. The joint torque sensor 100 in the present invention is in direct contact with the joint, so it can withstand the torques of Mx, My, and Mz. The joint torque sensor 100 is a three-dimensional torque sensor 100, so it can detect the information of Mx, My, and Mz. At the same time, compared with the existing technology in which the traditional torque sensor is installed separately from the output flange, the joint torque sensor 100 in this scheme can detect the information of Mx and My, so it can at least partially decouple Mz according to the information of Mx and My to improve the detection accuracy of Mz. That is, the joint torque sensor 100 is used to calibrate the torque at least partially according to the bending moment, so it can calculate the deformation of the joint through the torque information of Mx and My, and further calculate the deformation of the three rotation directions of the entire robot, thereby improving the absolute positioning accuracy of the robot. Furthermore, through the torque information of Mx and My, by calibration means, at least partially decouple Mz according to the information of Mx and My, the comprehensive accuracy of the Mz direction of the robot can be further improved.
[0032] The joint torque sensor 100 includes a measuring beam 3 and a supporting beam 4, wherein the measuring beam 3 connects the outer ring 2 and the inner ring 1, and the supporting beam 4 connects the outer ring 2 and the inner ring 1, and the measuring beam 3 and the supporting beam 4 are distributed along the circumference of the joint torque sensor 100. In one embodiment of the present invention, the measuring beam 3 and the supporting beam 4 are both plate-shaped beams, and at least one supporting beam 4 is arranged between adjacent measuring beams 3. Preferably, the thickness of the measuring beam 3 is consistent with that of the supporting beam 4, or the thicknesses of the two are relatively close, and at this time, the stiffness and sensitivity performance of the joint torque sensor 100 are both maintained at a relatively good level.
[0033] In another embodiment of the present invention, Figure 3, the measuring beam 3 is formed as a plate-shaped beam, and the plate-shaped beam is arranged parallel to the horizontal plane, and the supporting beam 4 is formed as a plate-shaped beam, and the supporting beam 4 is arranged perpendicular to the horizontal plane, that is, the supporting beam 4 and the measuring beam 3 are arranged perpendicular to each other. By setting the supporting beam as a plate-shaped beam perpendicular to the horizontal plane, the joint torque sensor 100 of the robot joint is mainly subjected to torsional force, so the joint torque sensor 100 needs to have reasonable rigidity in the torque direction. Setting the supporting beam 4 as a plate-shaped beam perpendicular to the horizontal plane can reasonably adjust the various stiffness of the joint torque sensor 100, so that the stiffness of the joint torque sensor 100 is within an appropriate range. At the same time, the measuring beam 3 is a plate-shaped beam parallel to the horizontal plane. After multiple simulation tests, it is found that such a design facilitates the sensitive force of the measuring beam, and the detection accuracy of the joint torque sensor is better.
[0034] Further, see Figure 4 , Figure 4A schematic diagram of the strain gauge 31 patch of the joint torque sensor 100 of an embodiment of the present invention is shown. The joint torque sensor includes at least two measuring beams, the at least two measuring beams are symmetrical relative to the center of the joint torque sensor, the strain gauges 31 are symmetrically attached to the upper and lower surfaces of the measuring beam 3, and the strain gauges 31 attached to the at least two measuring beams 3 are symmetrical relative to the center of the joint torque sensor. The robot joint detects the torque of the joint through the joint torque sensor, so the interference of other dimensional forces on the torque detection should be avoided as much as possible, thereby improving the accuracy of the torque output by the joint torque sensor. According to multiple experiments and analyses, for My, Fx, and Fz force information, the output of a single shear strain gauge 31 is almost 0, that is, the interference caused by it can be ignored; for the force of Mx, by ensuring that the force on a measuring beam is balanced, the interference of Mx can be offset, that is, by symmetrically pasting the shear strain gauge 31 on the upper and lower surfaces of the measuring beam, the interference of Mx can be offset; for the force of Fy, the strain gauges 31 pasted by at least two measuring beams are symmetrical relative to the center of the joint torque sensor, that is, the strain gauge 31 of one measuring beam and the strain gauge 31 of another measuring beam with a phase difference of 180 degrees can form a full-bridge decoupling circuit, thereby eliminating the interference of Fy. Through the above design, the detection accuracy of the joint torque sensor can be improved, thereby improving the detection accuracy of the robot joint. At the same time, the strain gauges are pasted on the upper and lower surfaces of the measuring beam, and the measuring beam is a plate-shaped beam parallel to the horizontal plane, and the patch is easy and easy to process. The joint torque sensor 100 provided by the present invention can replace the output flange of the original joint and can detect the torque information of the joint. The output flange is usually connected to the housing of the joint to transmit the power of the joint. The joint torque sensor 100 in the present invention can also be used to be connected to the housing of the joint, so that the joint torque sensor 100 can be subjected to the torque of Mx, My and Mz. In one embodiment of the present invention, the outer ring 2 is provided with a groove 21 at the position corresponding to the connection of the measuring beam 3, and the groove 21 is provided along the outer edge of the outer ring 2. Specifically, the joint torque sensor 100 includes at least two measuring beams 3, and correspondingly, includes at least two grooves 21, and the number of the grooves 21 is consistent with the number of the measuring beams 3. Specifically, the groove 21 extends along the outer edge of the outer ring 2, and the circumferential extension distance of the groove 21 in the outer ring 2 is greater than the extension distance of the outer ring 2 corresponding to the measuring beam 3. By setting the above-mentioned groove 21, when the joint torque sensor 100 is installed on the robot joint, uneven force may occur when it cannot be installed completely in a close fit. The setting of the groove 21 prevents the detection result of a certain measuring beam 3 from deviating significantly from the actual value when the joint torque sensor 100 is subjected to uneven force, thereby making the joint torque sensor 100 work stably and the detection more accurate.
[0035] In order to avoid the possibility that the detection result of the joint torque sensor 100 is not accurate due to uneven force, in another embodiment of the present invention, along the axial direction of the joint torque sensor 100, the upper and lower surfaces of the measuring beam 3 are recessed relative to the inner ring 1. Therefore, when there is a gap between the upper and lower sides of the joint torque sensor 100, the recessed design can avoid the axial force imbalance of the joint torque sensor; and when the friction of the joint torque sensor in the circumferential direction is uneven, the recessed design can avoid the circumferential force imbalance of the joint torque sensor. By setting the recess, the detection result of a certain measuring beam 3 can be prevented from deviating significantly from the actual value, so that the joint sensor can work stably and the detection is more accurate.
[0036] In one embodiment of the present invention, the wall thickness of the outer ring 2 corresponding to the measuring beam 3 is smaller than the wall thickness of the outer ring 2 corresponding to the support beam 4. That is, the wall thickness of the outer ring 2 corresponding to the position where the measuring beam 3 is connected is slightly smaller, and the wall thickness of the outer ring 2 corresponding to the position where the support beam 4 is connected is slightly larger. By setting the wall thickness of the outer ring 2 corresponding to the measuring beam 3 to be smaller, when the positions of the inner ring 1 and the outer ring 2 have been determined, the length of the measuring beam 3 is slightly increased, and the length of the measuring beam 3 is greater than the length of the support beam 4, which is more conducive to the deformation of the measuring beam 3, and is conducive to increasing the sensitivity of the measuring beam 3, and is also conducive to the measurement beam Paste the strain gauge, increasing the space for pasting the strain gauge. Further, the length of the measuring beam 3 is greater than the length of the support beam 4, and the length of the measuring beam 3 is less than twice the length of the support beam 4, that is, the length of the measuring beam 3 is greater than the length of the support beam 4, but less than twice the length of the support beam 4, so that the sensitivity of the measuring beam 3 is improved, and it is also conducive to the compact design of the robot joint.
[0037] As mentioned above, the joint torque sensor 100 can be used as an output flange. Since it needs to play the function of the torque sensor 100 at the same time, compared with the traditional output flange, the output flange itself is a solid design, has better rigidity, and can have a better supporting effect. The joint torque sensor 100 in the present invention needs to play the function of detecting torque. The support beam 4 and the measuring beam 3 of the joint torque sensor 100 have a supporting effect, and the outer ring 2 and the inner ring 1 are not solid structures, and the supporting effect is limited. In one embodiment of the present invention, the joint torque sensor 100 includes an overload protection beam 5 extending from the outer ring 2 to the inner ring 1, and the overload protection beam 5 forms a gap with the inner ring 1. By setting the gap, when the torque sensor 100 is overloaded, the existence of the gap can at least partially alleviate the overload and avoid damage to the torque sensor 100. Further, the inner ring 1 includes a plurality of locking holes 11 distributed circumferentially along the outer edge, and the overload protection beam 5 is arranged between adjacent locking holes 11 and forms gaps with the adjacent locking holes 11 respectively. That is, a gap is formed between the overload protection beam 5 and the inner ring 1, and a gap is formed with the locking hole 11 distributed on the outer edge of the inner ring 1 and adjacent to the overload protection beam 5. The overload protection beam 5 and the outer edge of the inner ring 1, as well as the adjacent locking hole 11 form a three-sided gap, further enhancing the overload protection effect of the joint torque sensor 100.
[0038] Furthermore, the inner ring includes a plurality of locking holes distributed circumferentially along the outer edge, the support beam is arranged between adjacent locking holes, and the support beam arranged between the adjacent locking holes forms a gap with the adjacent locking holes to further enhance the overload protection effect of the joint torque sensor. Furthermore, more than one support beam may be arranged between the adjacent locking holes, and a plurality of support beams located between the adjacent locking holes form a gap with the adjacent locking holes as a whole to enhance the overload protection effect of the joint torque sensor.
[0039] The joint torque sensor 100 is used to be connected to the outer shell of the joint. In one embodiment of the present invention, the outer ring 2 includes a connection hole 22 extending in the radial direction, and the connection hole 22 is formed at the corresponding position of the outer ring 2 where the overload protection beam 5 is set. There is a gap between the overload protection beam 5 and the inner ring 1, so that when the joint torque sensor 100 is connected, it is prevented that the joint torque sensor 100 is subjected to an unbalanced force due to the pre-tightening force of the connection, so that the detection of the joint torque sensor is inaccurate. The joint torque sensor can be connected to the next joint through the connection hole. The joint torque sensor in this embodiment can be connected to the next joint through the radially extending connection hole. In other embodiments of the present invention, the connection hole can also be in other forms. For example, the outer ring includes a connection hole extending in the axial direction, and the connection holes are distributed along the circumference of the outer ring. The joint torque sensor is connected to the next joint through the axially extending connection hole.
[0040] The beneficial effects of the above preferred embodiments are: the joint torque sensor includes an input connecting flange and an output connecting flange, so that it can directly replace the output flange of the joint and can detect the torque information at the same time. At the same time, by reasonably distributing the support beam 4 and the measuring beam 3, and adjusting the size settings of the two, the stiffness is better while maintaining the accuracy of the joint torque sensor.
[0041] The present invention also protects a robot joint, Figure 5 , the robot joint 200 includes a housing 210, a motor, a reducer, and the joint torque sensor 100 described in any of the above, the input connection flange of the joint torque sensor 100 is connected to the output end of the reducer, and the output connection flange is used to connect to another joint of the robot to transfer the force / torque of the output end of the reducer to the other joint. The motor shaft of the motor is connected to the input end of the reducer, the input end of the reducer is the high-speed end, the output end of the reducer is the low-speed end, and the output end of the reducer is connected to the joint torque sensor 100, and the joint torque sensor 100 transfers the force / torque of the output end of the reducer to the next joint. The joint torque sensor 100 includes a plurality of locking holes 11 circumferentially distributed on the outer edge of the inner ring 1, and the joint torque sensor 100 is connected to the output end of the reducer through the locking holes 11.
[0042] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.
Claims
1. A joint torque sensor, characterized in that: It includes an inner ring, an outer ring, and at least two measuring beams and at least two supporting beams connecting the inner ring and the outer ring, the measuring beams are pasted with strain gauges, the supporting beams are used to enhance the rigidity of the joint torque sensor, one of the inner ring and the outer ring is an input connecting flange, and the other is an output connecting flange, the number of the supporting beams is greater than or equal to the number of the measuring beams, and at least one supporting beam is arranged between adjacent measuring beams; along the axial direction of the joint torque sensor, the height of the supporting beam is greater than the height of the measuring beam; the outer ring is provided with a groove at the position corresponding to the connection of the measuring beam , the groove is arranged along the outer edge of the outer ring; the measuring beam is formed as a plate-shaped beam, and the plate-shaped beam is arranged parallel to the horizontal plane; the joint torque sensor includes an overload protection beam extending from the outer ring to the inner ring, and the overload protection beam forms a gap with the inner ring; the inner ring includes a plurality of locking holes distributed circumferentially along the outer edge, and the overload protection beam is arranged between adjacent locking holes and forms gaps with the adjacent locking holes respectively; the supporting beam is formed as a plate-shaped beam, and the supporting beam is arranged perpendicular to the horizontal plane; the wall thickness of the outer ring corresponding to the measuring beam is smaller than the wall thickness of the outer ring corresponding to the supporting beam.
2. The joint torque sensor according to claim 1, characterized in that: The joint torque sensor is a three-dimensional torque sensor, and the joint torque sensor is used to detect bending moment and torque.
3. The joint torque sensor according to claim 2, characterized in that: The joint torque sensor is used to calibrate the torque at least partially according to the bending moment, and output the torque calibrated according to the bending moment.
4. The joint torque sensor according to claim 1, characterized in that: The at least two measuring beams are symmetrical relative to the center of the joint torque sensor, and shear strain gauges are symmetrically pasted on the upper and lower surfaces of the measuring beams. The strain gauges pasted on the at least two measuring beams are symmetrical relative to the center of the joint torque sensor.
5. A robot joint, characterized in that: It includes a housing, a motor, a reducer, and a joint torque sensor according to any one of claims 1 to 4, wherein the input connecting flange is connected to the output end of the reducer, and the output connecting flange is used to connect to the housing of another joint of the robot to transmit the force and / or torque at the output end of the reducer to the other joint.