Patch positioning device for multi-dimensional force sensor

Abstract

The application provides a patch positioning device of a multi-dimensional force sensor, the multi-dimensional force sensor comprising a plurality of elastic beams and a plurality of strain gauges; the elastic beam has a first patch surface and a second patch surface adjacent along the circumferential direction of the elastic beam, and the patch surfaces are respectively attached with the strain gauges. The device comprises an image acquisition assembly and a distance acquisition assembly. The image acquisition assembly comprises a two-dimensional image acquisition part and a first mounting part, the two-dimensional image acquisition part acquires two-dimensional image information of the multi-dimensional force sensor towards the second patch surface, and the first mounting part drives the position of the two-dimensional image acquisition part relative to the system coordinate system of the patch positioning device to be adjustable. The distance acquisition assembly comprises a distance acquisition part and a second mounting part, and the second mounting part drives the position of the distance acquisition part relative to the system coordinate system to be adjustable. The application does not need to manually adjust the measurement patch position, and also does not need to manually adjust the positions of the two-dimensional image acquisition part and the distance acquisition part, thereby improving the determination efficiency and accuracy of the patch position.

Description

Technical Field

[0001] This utility model relates to the field of sensor manufacturing technology, and in particular to a patch positioning device for a multidimensional force sensor. Background Technology

[0002] A multi-dimensional force sensor is a sensor capable of simultaneously detecting forces in multiple directions. It outputs forces or torques in various directions in space as corresponding electrical signals, thereby accurately sensing the force conditions on the measured object. As a core sensing element, multi-dimensional force sensors have been widely used in many fields such as industrial automation, aerospace, medical, automotive manufacturing, and precision testing. The measurement accuracy, stability, and lifespan of a multi-dimensional force sensor directly determine the performance of the entire system. The strain gauge, as the core sensing element of a multi-dimensional force sensor, has its mounting process being a crucial step in its manufacturing. The accuracy of the strain gauge's mounting position on the sensor's elastic beam determines the sensor's sensing sensitivity and stability.

[0003] Traditional strain gauge placement relies primarily on mechanical scribing combined with manual visual alignment. However, as sensors become increasingly precise and miniaturized, the traditional manual placement method is problematic. This is because strain gauges are small and come in many different specifications, each with varying precision requirements. Manual visual alignment struggles to guarantee micron-level positioning accuracy. Even slight deviations in placement can increase non-linearity in the sensor's output signal, potentially impacting its measurement range and lifespan. Furthermore, differences in operator habits and experience during manual placement can lead to significant performance and quality variations even within the same batch of sensors.

[0004] To ensure the accuracy of patch placement, existing technologies use a combination of cameras and vision processing to determine patch position. This typically involves placing cameras on one or both sides of a multi-dimensional force sensor to capture images, and then using vision processing to identify the target patch position within the images. However, in this method, the cameras are usually fixed to one or both sides of the sensor. For multiple strain gauges of different sizes and types, the camera position needs to be manually adjusted each time a strain gauge is replaced. This approach is not only inefficient, but also suffers from the inability to guarantee the accuracy of manually adjusting the camera position. The camera's position (angle, distance, etc.) directly affects the image recognition accuracy, thus this method still cannot guarantee the precise positioning of the patch.

[0005] Therefore, in the existing technology, when multi-dimensional force sensors are used to attach strain gauges, there is a problem that the positioning accuracy of the attachment position is difficult to guarantee. Utility Model Content

[0006] The purpose of this invention is to solve the problem that the positioning accuracy of strain gauges is difficult to guarantee when multidimensional force sensors are applied in the prior art.

[0007] To address the aforementioned problems, this utility model discloses a patch positioning device for a multidimensional force sensor. The multidimensional force sensor includes multiple elastic beams and multiple strain gauges. At least one elastic beam has a first patch surface and a second patch surface adjacent to each other along the circumferential direction of the elastic beam, and corresponding strain gauges are attached to the first patch surface and the second patch surface, respectively. Furthermore, the patch positioning device includes: an image acquisition component disposed on one side of the multidimensional force sensor, comprising a two-dimensional image acquisition part and a first mounting part, the two-dimensional image acquisition part being fixedly connected to the first mounting part; the two-dimensional image acquisition part acquires two-dimensional image information of the multidimensional force sensor facing the second patch surface, and the first mounting part allows the position of the two-dimensional image acquisition part relative to the system coordinate system of the patch positioning device to be adjustable; and a distance acquisition component disposed on one side of the multidimensional force sensor, comprising a distance acquisition part and a second mounting part, the distance acquisition part being fixedly connected to the second mounting part; the distance acquisition part is arranged facing the second patch surface, and the second mounting part allows the position of the distance acquisition part relative to the system coordinate system to be adjustable.

[0008] According to another specific embodiment of the present invention, the patch positioning device for a multi-dimensional force sensor disclosed in this embodiment has an adjustable position of a first mounting part relative to the longitudinal axis of the system coordinate system, which drives the two-dimensional image acquisition part. The first mounting part includes a support beam, a first guide rail, and a first slider adapted to the first guide rail. The support beam is disposed on a target mounting surface along a first direction parallel to the longitudinal axis. The first guide rail is fixedly disposed on the side of the support beam away from the target mounting surface and extends along the first direction. The first slider is slidably connected to the first guide rail, and the two-dimensional image acquisition part is movably disposed on the first slider.

[0009] According to another specific embodiment of the present invention, the patch positioning device for the multidimensional force sensor disclosed in this embodiment of the present invention has an I-shaped cross-section for the first guide rail; the first mounting part further includes a first mounting bracket, the side of the first mounting bracket near the target mounting surface is fixedly connected to the first slider, and the two-dimensional image acquisition part is fixedly disposed on the other side of the first mounting bracket; a positioning bracket is also fixedly disposed on at least one side of the first mounting bracket along a second direction parallel to the horizontal axis of the system coordinate system, the positioning bracket is L-shaped and includes a first positioning plate and a second positioning plate perpendicular to each other, the first positioning plate is fixedly connected to the first mounting bracket, the second positioning plate is parallel to and spaced apart from the top of the support beam, and the second positioning plate is provided with a positioning hole for the positioning pin to pass through.

[0010] According to another specific embodiment of the present invention, the patch positioning device for the multi-dimensional force sensor disclosed in this embodiment allows the position of the first mounting part relative to the horizontal axis of the system coordinate system to be adjustable. The first mounting part further includes a support bracket and guide members disposed on both sides of a support beam along a second direction. The support bracket is disposed between the support beam and the target mounting surface, along the second direction, and a groove is provided on the top of the side of the support bracket away from the target mounting surface. The guide members include a first guide part fixedly connected to the support beam and a second guide part slidably connected to the groove, with the first and second guide parts fixedly connected.

[0011] According to another specific embodiment of the present invention, the patch positioning device for the multidimensional force sensor disclosed in this embodiment of the present invention includes at least two support brackets arranged parallel to and spaced apart along a first direction; wherein, two of the at least two support brackets are respectively arranged at both ends of the support beam along the first direction.

[0012] According to another specific embodiment of the present invention, the patch positioning device for the multi-dimensional force sensor disclosed in this embodiment of the present invention includes a 2D camera as the two-dimensional image acquisition unit; the two-dimensional image acquisition unit acquires two-dimensional image information along a direction perpendicular to the second patch surface. Furthermore, the image acquisition component also includes a light source support and an illumination source; wherein, the light source support is disposed in a first direction between the two-dimensional image acquisition unit and the multi-dimensional force sensor, and the illumination source is fixedly connected to the light source support; the axis of the illumination source coincides with the first direction.

[0013] According to another specific embodiment of the present invention, the patch positioning device for the multi-dimensional force sensor disclosed in this embodiment of the present invention has an adjustable position of the second mounting part relative to the horizontal axis of the system coordinate system, wherein the second mounting part includes a base, a second guide rail, and a second slider adapted to the second guide rail; the base is fixedly disposed on the target mounting surface along a second direction; the second guide rail is fixedly disposed on the side of the base away from the target mounting surface, and the second guide rail extends along the second direction; the second slider is slidably connected to the second guide rail, and the distance acquisition part is movably disposed on the second slider.

[0014] According to another specific embodiment of the present invention, the patch positioning device for the multidimensional force sensor disclosed in this embodiment further includes a lead screw adjustment mechanism in the second mounting part; wherein, the lead screw adjustment mechanism is fixedly disposed on one end of the base along the second direction, and includes a first support seat, a lead screw nut, a lead screw body and an adjustment knob; the first support seat is fixedly disposed on the end of the base along a direction perpendicular to the target mounting surface, and a lead screw fixing hole is provided on the first support seat; the lead screw body is disposed along the second direction, and the lead screw nut is fixedly disposed on the side of the second slider near the first support seat; one end of the lead screw body passes through the lead screw fixing hole and engages with the lead screw nut, and the other end is fixedly connected to the adjustment knob.

[0015] According to another specific embodiment of the present invention, the patch positioning device for a multi-dimensional force sensor disclosed in this embodiment includes a distance acquisition component disposed in a first direction between an image acquisition component and a multi-dimensional force sensor; the distance acquisition component is a laser rangefinder or an ultrasonic rangefinder; the cross-section of the second guide rail is I-shaped; and a second support seat is provided at the end of the base away from the lead screw adjustment mechanism along the second direction, and a limiting part is provided on the side of the second support seat near the base; the second mounting part also includes a second mounting bracket, the side of the second mounting bracket near the target mounting surface is fixedly connected to the second slider, and the distance acquisition component is fixedly disposed on the other side of the second mounting bracket; and the second mounting bracket includes a support column, a sliding member, and a fixing plate; wherein, the support column extends in a direction perpendicular to the target mounting surface, and one end of the support column is fixedly connected to the second slider; the sliding member is slidably connected to the support column, and the sliding member is fixedly connected to one side of the fixing plate, and the distance acquisition component is fixedly connected to the other side of the fixing plate.

[0016] According to another specific embodiment of the present invention, the patch positioning device for the multi-dimensional force sensor disclosed in this embodiment further includes a clamping fixture; wherein, the clamping fixture is disposed on one side of the image acquisition component and the distance acquisition component, and includes a third mounting part, a rotation drive part, a rotation shaft, and a clamping part; the rotation drive part is fixedly disposed on the third mounting part, the rotation shaft is rotatably disposed on the third mounting part, and one end of the rotation shaft is connected to the output end of the rotation drive part for transmission, and the other end is fixedly connected to one side of the clamping part; the multi-dimensional force sensor is detachably connected to the other side of the clamping part. Furthermore, the rotation axis of the rotation shaft is parallel to the first direction.

[0017] The beneficial effects of this utility model are:

[0018] This application, by setting up image acquisition components and distance acquisition components, allows for the comprehensive calculation of patch positions based on two-dimensional image information and distance information. Compared to manual operation, this effectively improves accuracy and efficiency. Furthermore, both the image acquisition unit and the distance acquisition unit are positionally adjustable within the system coordinate system, enabling rapid adaptation to sensors and strain gauges of different sizes or specifications. This eliminates the need for manual calibration of the image acquisition unit and distance acquisition unit, avoiding accuracy errors caused by human operation. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the multidimensional force sensor in the patch positioning device of the multidimensional force sensor provided in this embodiment of the utility model;

[0020] Figure 2 This is a schematic diagram of the patch positioning device for the multidimensional force sensor provided in this embodiment of the utility model;

[0021] Figure 3 This is a schematic diagram of the image acquisition component of the patch positioning device for the multidimensional force sensor provided in this embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the distance acquisition component of the patch positioning device for the multidimensional force sensor provided in this embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the clamping fixture of the patch positioning device for the multidimensional force sensor provided in this embodiment of the utility model.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. Multidimensional force sensor; 11. Elastic beam; 12. Strain gauge; 13. First patch surface; 14. Second patch surface; 15. Force transmission platform; 16. Annular mounting base; 2. Two-dimensional image acquisition unit; 3. First mounting unit; 4. Distance acquisition unit; 5. Second mounting unit; 51. Base; 52. Second guide rail; 53. Second slider; 54. First support base; 55. Lead screw nut; 56. Lead screw body; 57. Adjustment knob; 58. Second support base; 581. Limiting part; 59. Second mounting bracket; 6. Light source support unit; 7. Illumination source; 8. Clamping fixture; 81. Third mounting unit; 82. Rotation drive unit; 83. Clamping part. Detailed Implementation

[0026] As described in the background section, existing multi-dimensional force sensor positioning methods that rely on manual visual alignment during patch placement struggle to guarantee micron-level positioning accuracy and are highly wasteful of human resources. While positioning methods combining cameras and vision processing are feasible, the camera is typically fixed to one or both sides of the sensor, requiring manual repositioning of the camera each time a strain gauge is replaced. This approach is not only inefficient but also fails to guarantee positioning accuracy.

[0027] To address the aforementioned technical problems, this embodiment provides a patch positioning device for a multi-dimensional force sensor. This device includes an image acquisition component and a distance acquisition component. The image acquisition component acquires two-dimensional image information of the multi-dimensional force sensor, and the distance acquisition component acquires distance information between the sensor and the multi-dimensional force sensor. The patch position can then be determined using the two-dimensional image information and the distance information, eliminating the need for manual adjustment and measurement, reducing manpower waste, and improving the efficiency of patch position determination. Furthermore, the positions of the two-dimensional image acquisition unit and the distance acquisition unit are adjustable under the influence of the first mounting unit and the second mounting unit, ensuring the position adjustment accuracy of the two-dimensional image acquisition unit and the distance acquisition unit, thereby improving the positioning accuracy of the patch.

[0028] Next, the patch positioning device for the multidimensional force sensor will be described in detail with reference to the accompanying drawings.

[0029] First, refer to Figure 1 The structure of the multidimensional force sensor 1 is described.

[0030] The multidimensional force sensor 1 includes multiple elastic beams 11 and multiple strain gauges 12. At least one elastic beam 11 has a first patch surface 13 and a second patch surface 14 that are adjacent to each other along the circumferential direction of the elastic beam 11, and the first patch surface 13 and the second patch surface 14 are respectively attached with corresponding strain gauges 12.

[0031] Specifically, the elastic beam 11 is generally made of alloy steel, aluminum alloy, or titanium alloy to ensure the strength and elastic deformation characteristics of the sensor, thus enabling it to undergo minute deformation under stress and reducing the risk of fatigue damage. The elastic beam 11 is generally a cuboid structure. The first patch surface 13 is generally the upper and lower surfaces of the elastic beam 11 (surfaces parallel to the XOY plane), used to attach strain gauges 12 for detecting forces in the X and Y axes. The second patch surface 14 is generally the front and rear surfaces of the elastic beam 11 (surfaces parallel to the XOZ plane), used to attach strain gauges 12 for detecting forces in the X and Z axes. The included angle between the first patch surface 13 and the second patch surface 14 is 90°. In other possible implementations, the elastic beam 11 can be a prism structure with a polygonal cross-section (e.g., a regular hexagon or octagon), and the first patch surface 13 can be any two adjacent sides of the polygon. Of course, the elastic beam 11 can also be configured as a cylindrical or elliptical cylinder structure. In this case, the strain gauge 12 will also have an arc-shaped sheet structure with the same degree of curvature as the elastic beam 11. When the elastic beam 11 is configured as a cylindrical or elliptical cylinder structure, the circumferential wall of the elastic beam 11 can be divided into multiple regions corresponding to the number of strain gauges 12 attached to the circumference of the elastic beam 11, and any two adjacent regions are the first attachment surface 13 and the second attachment surface 14.

[0032] The strain gauge 12 can be a resistance strain gauge, a thin film strain gauge, or a semiconductor strain gauge, and the strain gauge type on each patch surface can be the same or different.

[0033] More specifically, the number of elastic beams 11 is at least two, and at least one strain gauge 12 is attached to the patch surface of each elastic beam 11. In one specific implementation, the multidimensional force sensor 1 may include four elastic beams 11 (two along the X-axis and two along the Z-axis), and the four elastic beams 11 are arranged in a cross shape. One end of each of the four elastic beams 11 can be fixed to the force transmission platform 15 located at the center of the multidimensional force sensor 1, and the other end is connected to the annular mounting base 16 on the outer periphery of the sensor, thereby forming a symmetrical structure. Figure 1 The structure shown in the figure indicates that the shape of the annular mounting base 16 can be rectangular, circular, or other polygonal. In other possible implementations (not shown in the figure), the multidimensional force sensor 1 may also include four or more (e.g., five, six, or seven) elastic beams 11, one end of each elastic beam 11 being fixed to the annular mounting base 16 on the outer periphery of the sensor, and the other end being fixed to the force transmission platform 15 at the center of the sensor. Alternatively, the multidimensional force sensor 1 may also include two symmetrically and parallelly arranged elastic beams 11, with both ends of the two elastic beams 11 respectively fixed to the annular mounting base 16 on the outer periphery of the sensor.

[0034] Continue to refer to Figure 1"At least one elastic beam 11" means that among multiple elastic beams 11, only one elastic beam 11 may have two mutually perpendicular patch surfaces, or multiple (two or more) elastic beams 11 may all have this structure. "Corresponding strain gauges 12 are attached to the first patch surface 13 and the second patch surface 14 respectively" means that the type, specifications, and quantity of strain gauges 12 attached to the two perpendicular patch surfaces are adapted to the structure of the patch surfaces and the testing requirements. For example, one strain gauge 12 can be attached to both the first patch surface 13 and the second patch surface 14; or two strain gauges 12 can be attached to both the first patch surface 13 and the second patch surface 14, with the two strain gauges 12 on each patch surface symmetrically arranged; or one strain gauge 12 can be attached to the first patch surface 13 and two strain gauges 12 can be attached to the second patch surface 14; or strain gauges 12 can be attached to each patch surface in a 2×2 array arrangement.

[0035] Next, refer to Figure 2 The structure of the patch positioning device is described.

[0036] The patch positioning device includes an image acquisition component and a distance acquisition component. The image acquisition component is used to acquire two-dimensional image information of the multi-dimensional force sensor 1, and the distance acquisition component is used to acquire distance information between the multi-dimensional force sensor 1 and the multi-dimensional force sensor 1. Subsequently, the three-dimensional coordinates corresponding to the patch position of the strain gauge 12 relative to the system coordinate system on the patch surface can be calculated based on the two-dimensional image information and the distance information.

[0037] It should be noted that the system coordinate system of the patch positioning system refers to the three-dimensional rectangular coordinate system (denoted as O-XYZ) preset in the patch positioning system. This system coordinate system is used to uniformly calibrate the positions of the two-dimensional image acquisition unit 2, the distance acquisition unit 4, and the multi-dimensional force sensor 1, etc. Its origin can be set as the mechanical reference point of the patch positioning system (e.g., the center of the operating table, the center point of the two-dimensional image acquisition unit 2, or the center point of the multi-dimensional force sensor 1). The horizontal axis of the system coordinate system is the X-axis, the vertical axis is the Y-axis, and the vertical axis is the Z-axis.

[0038] In this patch positioning device, an image acquisition component is disposed on one side of the multi-dimensional force sensor 1, and includes a two-dimensional image acquisition unit 2 and a first mounting unit 3, with the two-dimensional image acquisition unit 2 fixedly connected to the first mounting unit 3. The two-dimensional image acquisition unit 2 acquires two-dimensional image information of the multi-dimensional force sensor 1 towards the second patch surface 14, and the first mounting unit 3 makes the position of the two-dimensional image acquisition unit 2 adjustable relative to the system coordinate system of the patch positioning device.

[0039] Specifically, the two-dimensional image acquisition unit 2 can be any 2D camera, which refers to a camera that directly captures two-dimensional images without needing to obtain the sensor's image by generating point clouds.

[0040] The first mounting part 3 is used to drive the two-dimensional image acquisition part 2 to adjust its position to adapt to multi-dimensional force sensors 1 of different sizes and types. In one possible implementation, the first mounting part 3 can be a slide module. The slide module includes an X-axis slide, a Y-axis slide, and a Z-axis slide. Any one slide can move relative to the other two slides, and the three slides can automatically adjust in the X, Y, and Z directions under the drive of a servo motor. The two-dimensional image acquisition part 2 is fixed to the top of the top slide via a bracket. The movement of the slide allows for translational adjustment of the two-dimensional image acquisition part 2 parallel to the first patch surface 13, as well as height adjustment. The robotic arm has multi-degree-of-freedom adjustment capabilities, enabling it to move the two-dimensional image acquisition part 2 to any position in the system coordinate system. In other possible implementations, the first mounting part 3 can be a robotic arm, with the two-dimensional image acquisition part 2 fixedly mounted on the end effector of the robotic arm. The robotic arm is driven by a servo motor, enabling multi-directional and multi-angle position adjustment, thereby moving the two-dimensional image acquisition part 2 to any position in the system coordinate system.

[0041] The first direction is Figure 1 and Figure 2 The direction is parallel to the Y-axis (vertical axis).

[0042] The distance acquisition component is disposed on one side of the multidimensional force sensor 1 and includes a distance acquisition part 4 and a second mounting part 5. The distance acquisition part 4 is fixedly connected to the second mounting part 5. The distance acquisition part 4 is arranged facing the second patch surface 14, and the second mounting part 5 drives the distance acquisition part 4 to adjust its position relative to the system coordinate system.

[0043] Specifically, the distance acquisition unit 4 can be a laser rangefinder or an ultrasonic rangefinder. The second mounting unit 5 is used to drive the distance acquisition unit 4 to adjust its position.

[0044] The structure of the second mounting part 5 can be the same as that of the first mounting part 3, such as a slide module or a robotic arm. The structure of the second mounting part 5 can also be different from that of the first mounting part 3. For example, the second mounting part 5 can be set as a support assembly, including a fixed base, a telescopic arm and an angle adjustment base; the distance acquisition part 4 is fixed on the angle adjustment base, the telescopic arm can realize position adjustment along the extension direction of the Y axis, and the angle adjustment base can realize angle adjustment in the XOZ plane.

[0045] The working process of this patch positioning device is as follows:

[0046] refer to Figure 1 and Figure 2First, the multi-dimensional force sensor 1 is fixed on the operating table, and a system coordinate system is established with the geometric center of the sensor as the origin. The position of the two-dimensional image acquisition unit 2 is adjusted by the first mounting part 3 so that the image acquisition direction of the two-dimensional image acquisition unit 2 can capture at least a portion of the image of the second patch surface 14 and an image of some features of the first patch surface 13 associated with the second patch surface 14. The position of the distance acquisition unit 4 is adjusted by the second mounting part 5 so that the ranging point (laser emission point or ultrasonic sound emission point) of the distance acquisition unit 4 is aligned with the center position of the second patch surface 14, the detection distance is initialized, and the reference distance value is transmitted to the control device. Next, the two-dimensional image acquisition unit 2 acquires two-dimensional image information along the Y-axis, and the distance acquisition unit 4 acquires the distance information between itself and the sensor. Then, the two-dimensional image information and the distance information are transmitted to the control device. The control device has the transmission reference distance and the size parameters of the sensor pre-stored. The control device can calculate the three-dimensional coordinates corresponding to the patch position of the strain gauge 12 on the first patch surface 13 and the second patch surface 14 based on the above information.

[0047] When replacing strain gauges 12 or multi-dimensional force sensors 1 of different specifications, there is no need to manually disassemble the two-dimensional image acquisition unit 2 or the distance acquisition unit 4. Simply adjust the position of the two-dimensional image acquisition unit 2 or the distance acquisition unit 4 in the system coordinate system through the first mounting unit 3 and the second mounting unit 5 to quickly adapt to the new patch requirements and improve operating efficiency.

[0048] With this structure, by setting up image acquisition components and distance acquisition components, the patch position can be calculated comprehensively based on two-dimensional image information and distance information, effectively improving accuracy and efficiency compared to manual operation. Furthermore, both the two-dimensional image acquisition unit 2 and the distance acquisition unit 4 are positionally adjustable within the system coordinate system, allowing for quick adaptation to sensors and strain gauges 12 of different sizes or specifications. This eliminates the need for manual adjustment of the positions of the two-dimensional image acquisition unit 2 and the distance acquisition unit 4, avoiding accuracy errors caused by human operation.

[0049] Furthermore, in this patch positioning device, the position of the first mounting part 3 relative to the vertical axis of the system coordinate system is adjustable. In one implementation, the first mounting part 3 may include a support beam, a first guide rail, and a first slider adapted to the first guide rail; the support beam is disposed on the target mounting surface along a first direction; the first guide rail is fixedly disposed on the side of the support beam away from the target mounting surface and extends along the first direction; the first slider is slidably connected to the first guide rail, and the two-dimensional image acquisition part 2 is movably disposed on the first slider.

[0050] Specifically, the two-dimensional image acquisition unit 2 can move along the Y-axis under the drive of the first mounting unit 3, thereby making the distance between the two-dimensional image acquisition unit 2 and the multi-dimensional force sensor 1 adjustable, and thus adaptable to elastic beams 11 of different lengths on the X-axis. The target mounting surface refers to the mounting reference surface of the patch positioning device, which can be the surface of a fixed operating table or a mounting base plate. When set as a mounting base plate, a leveling bolt can be provided at the bottom of the base plate to correct the levelness of the mounting surface, so as to adapt to different installation scenarios. The support beam is fixed to the target mounting surface along the first direction, thereby providing stable support for the first guide rail, the first slider and the two-dimensional image acquisition unit 2. Specifically, it can be made of aluminum alloy profile, carbon steel profile or carbon fiber profile. The first guide rail can be a linear ball guide rail or a linear sliding guide rail; the first slider is adapted to the first guide rail and has balls or sliding bushings inside. The first guide rail is fixedly set on the side of the support beam away from the target mounting surface, that is, the top of the support beam. The two-dimensional image acquisition unit 2 is movably mounted on the first slider, wherein the two-dimensional image acquisition unit 2 can be mounted on the top of the first slider via a movable bracket. Mobility includes, but is not limited to, the ability of the two-dimensional image acquisition unit 2 to move along the X-axis, along the Y-axis, along the Z-axis, or to rotate about the X-axis relative to the XOY plane to adjust the pitch angle, or to rotate about the Z-axis relative to the XOZ plane to adjust the orientation. Specifically, the movable bracket can include a support column arranged along the Z-axis, a support plate arranged in the XOY plane, and a fixing block. The support plate can slide relative to the support column along the Z-axis, thereby enabling the two-dimensional image acquisition unit 2 to move relative to the first slider in the Z-axis direction. Furthermore, the support plate is provided with grooves arranged along the X and Y axes. The fixing block is used to fix the two-dimensional image acquisition unit 2, and the end of the fixing hole can slide within the groove, thereby enabling movement along the X or Y direction. Rotation relative to the XOY or XOZ plane can be achieved using a universal joint, for example, by connecting the fixing block and the two-dimensional image acquisition unit 2 via a universal joint.

[0051] During operation, when it is necessary to adjust the position of the two-dimensional image acquisition unit 2 along the longitudinal axis (Y-axis), the first slider is pushed to slide along the first guide rail. After sliding to the target position, the slider is fixed to the guide rail by the locking bolt on the slider, thus achieving the positioning of the two-dimensional image acquisition unit 2. If it is necessary to adapt to elastic beams 11 of different sizes, it is only necessary to slide the first slider to adjust the distance between the two-dimensional image acquisition unit 2 and the elastic beam 11, without disassembling the two-dimensional image acquisition unit 2, making the operation convenient.

[0052] Furthermore, in this patch positioning device, the first guide rail has an I-shaped cross-section. The I-shaped guide rail has a larger contact area with the slider, providing better guiding accuracy and load-bearing capacity.

[0053] Furthermore, in a preferred implementation, the first mounting part 3 of the patch positioning device further includes a first mounting bracket. The side of the first mounting bracket closest to the target mounting surface is fixedly connected to the first slider, and the two-dimensional image acquisition part 2 is fixedly disposed on the other side of the first mounting bracket. A positioning bracket is also fixedly disposed on at least one side of the first mounting bracket along a second direction parallel to the horizontal axis (X-axis) of the system coordinate system. The positioning bracket is L-shaped and includes a first positioning plate and a second positioning plate perpendicular to each other. The first positioning plate is fixedly connected to the first mounting bracket, and the second positioning plate is parallel to and spaced apart from the top of the support beam. The second positioning plate has positioning holes for positioning pins to pass through.

[0054] Specifically, the second direction is the direction of the X-axis. When the positioning pin passes through the positioning hole, the positioning bracket can be fixed relative to the first mounting bracket, thereby fixing the position of the two-dimensional image acquisition unit 2 relative to the Y-axis.

[0055] Furthermore, in a preferred implementation, the first mounting part 3 of the patch positioning device allows the position of the two-dimensional image acquisition part 2 relative to the horizontal axis of the system coordinate system to be adjustable. The first mounting part 3 further includes a support bracket and guide members disposed on both sides of the support beam along a second direction. The support bracket is disposed between the support beam and the target mounting surface, and is disposed along the second direction. A groove is provided on the top of the side of the support bracket away from the target mounting surface. The guide members include a first guide part fixedly connected to the support beam and a second guide part slidably connected to the groove, with the first and second guide parts fixedly connected.

[0056] In one specific implementation, the first guide part and the second guide part can be integrally formed as an L-shaped bracket. The first guide part is welded to the support beam, and the second guide part is provided with a boss that matches the slide groove. In other possible implementations, the first guide part can be a corner bracket, connecting plate, or welded part, and is fixedly connected to the support beam by bolts; the second guide part can be a T-block, dovetail block, or roller, and is adapted to the slide groove of the support bracket. The support beam is set on the slide groove of the support bracket by guide parts. When it is necessary to adjust the position of the two-dimensional image acquisition unit 2 along the X-axis, the support beam can be pushed to slide along the slide groove.

[0057] Furthermore, in this patch positioning device, the support bracket includes at least two support brackets that are parallel and spaced apart along a first direction. Two of the at least two support brackets are respectively located at both ends of the support beam along the first direction.

[0058] Specifically, two of the load-bearing supports are respectively set at both ends of the support beam along the Y-axis. If the support beam is long, one or more load-bearing supports can be added in the middle.

[0059] Furthermore, in this patch positioning device, the two-dimensional image acquisition unit 2 is a 2D camera. In a preferred implementation, the two-dimensional image acquisition unit 2 acquires two-dimensional image information along a direction perpendicular to the second patch surface 14. That is, the two-dimensional image acquisition unit 2 captures two-dimensional image information directly facing the second patch surface 14. Capturing the image at this position allows for a complete and clear capture of all geometric features of the second patch surface 14, as well as the geometric features of the first patch surface 13 associated with the second patch surface 14, improving the accuracy of subsequent strain gauge 12 patch placement determination.

[0060] Furthermore, refer to Figure 3 The image acquisition component also includes a light source support 6 and an illumination source 7. The light source support 6 is disposed in a first direction between the two-dimensional image acquisition unit 2 and the multi-dimensional force sensor 1. The illumination source 7 is fixedly connected to the light source support 6, and the axis of the illumination source 7 coincides with the first direction.

[0061] In one implementation, the illumination source 7 is generally ring-shaped. The light source support 6 includes a support base plate and a support upright plate arranged perpendicularly to each other. The support base plate is fixedly connected to the side of the support beam away from the target mounting surface, and the support upright plate is fixedly connected to the support base plate. The support upright plate has a through hole adapted to the inner ring area of ​​the illumination source 7. The illumination source 7 is fixedly disposed on one side of the support upright plate at the corresponding position of the through hole. The diameter of the through hole on the support upright plate matches the inner ring diameter of the illumination source 7, thereby ensuring that the light from the two-dimensional image acquisition unit 2 can pass through the through hole and illuminate the multi-dimensional force sensor 1. The illumination source 7 can be an LED light source or a halogen light source. In other possible implementations, the illumination source 7 can be configured as a box structure arranged circumferentially around the two-dimensional image acquisition unit 2, with an LED array embedded in the inner wall of the box. The light source support 6 is configured as a support plate fixed to the bottom of the box structure.

[0062] By setting the illumination source 7, the light on the surface of the multi-dimensional force sensor 1 can be evenly distributed, eliminating shadows and reflections on the patch surface, thus improving the contrast and clarity of the two-dimensional image information. The axis of the illumination source 7 coincides with the first direction, which can avoid light skew or obstruction.

[0063] Furthermore, in this patch positioning device, a reference Figure 4 The second mounting part 5 drives the distance acquisition part 4 to be adjustable in position relative to the horizontal axis of the system coordinate system. The second mounting part 5 includes a base 51, a second guide rail 52, and a second slider 53 adapted to the second guide rail 52. The base 51 is fixedly disposed on the target mounting surface along a second direction. The second guide rail 52 is fixedly disposed on the side of the base 51 away from the target mounting surface and extends along the second direction. The second slider 53 is slidably connected to the second guide rail 52, and the distance acquisition part 4 is movably disposed on the second slider 53.

[0064] Specifically, the second mounting part 5 makes the position of the distance acquisition part 4 relative to the X-axis of the system coordinate system adjustable. This not only allows for the adjustment of the optimal laser or ultrasonic emission position based on the structure of the multi-dimensional force sensor 1, but also ensures that the positions of the distance acquisition part 4 and the two-dimensional image acquisition part 2 are coordinated, thereby improving positioning accuracy.

[0065] When it is necessary to adjust the position of the distance acquisition unit 4 along the X-axis, the second slider 53 is pushed to slide along the second guide rail 52. After sliding to the target position, the second slider 53 can be fixed to the second guide rail 52 by the locking bolt on the slider, thereby achieving the positioning of the distance acquisition unit 4. Furthermore, the positions of the distance acquisition unit 4 and the two-dimensional image acquisition unit 2 on the X-axis can be adjusted synchronously according to the position of the elastic beam 11, ensuring that the distance acquisition unit 4 is aligned with the second patch surface 14, providing a precise distance basis for the positioning of the patch.

[0066] Furthermore, in this patch positioning device, the second mounting part 5 also includes a lead screw adjustment mechanism. The lead screw adjustment mechanism is fixedly disposed on one end of the base 51 along the second direction and includes a first support 54, a lead screw nut 55, a lead screw body 56, and an adjustment knob 57. The first support 54 is fixed to the end of the base 51 along a direction perpendicular to the target mounting surface, and a lead screw fixing hole is provided on the first support 54. The lead screw body 56 is disposed along the second direction, and the lead screw nut 55 is fixedly disposed on the side of the second slider 53 near the first support 54. One end of the lead screw body 56 passes through the lead screw fixing hole and engages with the lead screw nut 55, and the other end is fixedly connected to the adjustment knob 57.

[0067] When it is necessary to adjust the position of the distance acquisition unit 4 on the X-axis, rotate the adjustment knob 57 to rotate the lead screw body 56. The lead screw body 56 engages with the lead screw nut 55, thereby converting the rotational motion into linear motion, pushing the second slider 53 to slide along the second guide rail 52. After the distance acquisition unit 4 is adjusted to the target position, the lead screw has a self-locking function, so no additional locking is required to keep the position fixed, preventing the position of the distance acquisition unit 4 from shifting after adjustment, and further improving the accuracy of distance detection.

[0068] Furthermore, in this patch positioning device, a distance acquisition component is disposed in the first direction between the image acquisition component and the multi-dimensional force sensor 1. The distance acquisition unit 4 is a laser rangefinder or an ultrasonic rangefinder. The cross-section of the second guide rail 52 is I-shaped. A second support seat 58 is also provided at the other end of the base 51 away from the lead screw adjustment mechanism in the second direction, and a limiting part 581 is also provided on the side of the second support seat 58 near the base 51.

[0069] Specifically, the limiting part 581 takes the form of a limiting block or a limiting groove. The limiting block can be fixed to the side of the second support 58 near the base 51, and the limiting groove can be formed on the second support 58 and recessed in the direction away from the base 51. The limiting part 581 can limit the sliding stroke of the second slider 53 and prevent the second slider 53 from sliding excessively and disengaging from the guide rail.

[0070] Furthermore, in this patch positioning device, a reference Figure 4 The second mounting part 5 also includes a second mounting bracket 59. The side of the second mounting bracket 59 closest to the target mounting surface is fixedly connected to the second slider 53, and the distance acquisition part 4 is fixedly disposed on the other side of the second mounting bracket 59. Furthermore, the second mounting bracket 59 includes a support column, a slider, and a fixing plate. The support column extends in a direction perpendicular to the target mounting surface, and one end of the support column is fixedly connected to the second slider 53. The slider is slidably connected to the support column and fixedly connected to one side of the fixing plate, while the distance acquisition part 4 is fixedly connected to the other side of the fixing plate.

[0071] Specifically, the support column can be a metal rod, which is fixedly connected to the second slider 53 by bolts; the sliding element can be a linear bearing or a sliding bushing, which is fitted onto the support column and can slide up and down along the support column. The fixed plate is fixedly connected to the sliding element by bolts, and the distance acquisition part 4 can be fixed to the fixed plate by bolts.

[0072] By setting the second mounting bracket 59, the distance acquisition unit 4 can slide up and down relative to the support column under the action of the fixed plate and the sliding member, thereby adjusting the height of the distance acquisition unit 4 relative to the Z-axis.

[0073] Furthermore, in this patch positioning device, a reference Figure 5 The system also includes a clamping fixture 8; wherein the clamping fixture 8 is disposed on one side of the image acquisition component and the distance acquisition component, and includes a third mounting part 81, a rotation drive part 82, a rotation shaft, and a clamping part 83; the rotation drive part 82 is fixedly disposed on the third mounting part 81, the rotation shaft is rotatably disposed on the third mounting part 81, and one end of the rotation shaft is connected to the output end of the rotation drive part 82, and the other end is fixedly connected to one side of the clamping part 83; the multidimensional force sensor 1 is detachably connected to the other side of the clamping part 83. Furthermore, the rotation axis of the rotation shaft is parallel to the first direction.

[0074] Specifically, the third mounting part 81 is fixed to the target mounting surface, and can be an aluminum alloy bracket or a cast iron bracket. The rotation drive part 82 is used to drive the rotation of the rotating shaft, and can be a servo motor or a stepper motor. The rotating shaft is rotatably mounted on the third mounting part 81 via a rotating bearing, and its rotation axis is parallel to the first direction (Y-axis) to ensure that the first patch surface 13 of the elastic beam 11 remains parallel to the two-dimensional image acquisition part 2 and the second patch surface 14 is opposite to the distance acquisition part 4 during rotation. The clamping part 83 can be a three-jaw chuck or a clamp.

[0075] During operation, the multidimensional force sensor 1 is first clamped and fixed using the clamping part 83. Then, the positions of the two-dimensional image acquisition part 2 and the distance acquisition part 4 are adjusted so that one of the first patch surfaces 13 of the elastic beam 11 is parallel to the two-dimensional image acquisition part 2, and the corresponding second patch surface 14 is aligned with the distance acquisition part 4. After the first patch surface 13 and the second patch surface 14 are attached, the rotation drive part 82 is activated, driving the rotation shaft to rotate (the rotation angle is determined according to the angle of the patch surface). Figure 1 The structure shown corresponds to a rotation angle of 90°, which in turn drives the multi-dimensional force sensor 1 to rotate, causing the other first patch surface 13 of the elastic beam 11 to be parallel to the two-dimensional image acquisition unit 2, and the corresponding second patch surface 14 to be aligned with the distance acquisition unit 4. Multiple patch surfaces can be positioned without manual disassembly or adjustment of the multi-dimensional force sensor 1. After patching, the multi-dimensional force sensor 1 can be removed by releasing the clamping part 83, making disassembly highly convenient.

[0076] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A patch positioning device for a multi-dimensional force sensor, characterized by, The multi-dimensional force sensor comprises a plurality of elastic beams and a plurality of strain gauges; wherein at least one of the elastic beams has a first patch surface and a second patch surface adjacent along a circumferential direction of the elastic beam, and the first patch surface and the second patch surface are respectively attached with a corresponding strain gauge; and the patch positioning device comprises: An image acquisition component is arranged on one side of the multi-dimensional force sensor and comprises a two-dimensional image acquisition part and a first mounting part, and the two-dimensional image acquisition part is fixedly connected with the first mounting part; the two-dimensional image acquisition part acquires two-dimensional image information of the multi-dimensional force sensor towards the second patch surface, and the position of the two-dimensional image acquisition part relative to a system coordinate system of the patch positioning device is adjustable by the first mounting part; A distance acquisition component is arranged on one side of the multi-dimensional force sensor and comprises a distance acquisition part and a second mounting part, and the distance acquisition part is fixedly connected with the second mounting part; the distance acquisition part is arranged towards the second patch surface, and the position of the distance acquisition part relative to the system coordinate system is adjustable by the second mounting part.

2. The patch positioning device for a multi-dimensional force sensor of claim 1, wherein, The position of the two-dimensional image acquisition part relative to a longitudinal axis of the system coordinate system is adjustable by the first mounting part.

3. The patch positioning device for a multi-dimensional force sensor of claim 2, wherein, The position of the two-dimensional image acquisition part relative to a transverse axis of the system coordinate system is adjustable by the first mounting part.

4. The patch positioning device for a multi-dimensional force sensor of claim 2, wherein, The two-dimensional image acquisition part is a 2D camera. The two-dimensional image acquisition part acquires the two-dimensional image information in a direction perpendicular to the second patch surface.

5. The patch positioning device for a multi-dimensional force sensor of claim 2, wherein, The image acquisition component further comprises a light source support part and an illumination light source; wherein the light source support part is arranged between the two-dimensional image acquisition part and the multi-dimensional force sensor in a first direction parallel to the longitudinal axis, and the illumination light source is fixedly connected with the light source support part. The axis of the illumination light source coincides with the first direction.

6. The patch positioning device for a multi-dimensional force sensor of claim 1, wherein, The position of the distance acquisition part relative to the transverse axis of the system coordinate system is adjustable by the second mounting part.

7. The patch positioning device for a multi-dimensional force sensor of claim 2, wherein, The distance acquisition component is arranged between the image acquisition component and the multi-dimensional force sensor in the first direction parallel to the longitudinal axis.

8. The patch positioning device for a multi-dimensional force sensor of claim 7, wherein, The distance acquisition part is a laser range finder or an ultrasonic range finder.

9. The patch positioning device for a multi-dimensional force sensor according to claim 5 or 7, wherein Further comprising a clamping tool; wherein the clamping tool is arranged on one side of the image acquisition component and the distance acquisition component and comprises a third mounting part, a rotation driving part, a rotation shaft and a clamping part; The rotation driving part is fixedly arranged on the third mounting part, the rotation shaft is rotatably arranged on the third mounting part, one end of the rotation shaft is in transmission connection with the output end of the rotation driving part, and the other end is fixedly connected with one side of the clamping part.

10. The patch positioning device for a multi-dimensional force sensor of claim 9, wherein, The multi-dimensional force sensor is detachably connected to the other side of the clamping part; and the rotation axis of the rotation shaft is parallel to the first direction.

Images