Sensing assemblies, force / torque sensor assemblies and robot joints

Abstract

To provide a force / torque sensor assembly that causes linearity between a relative motion and a sensor signal.SOLUTION: The present application provides a sensing assembly. The sensing assembly is configured to detect a relative motion between a first component and a second component, and the sensing assembly includes a magnet assembly configured to be connected to the first component, and a pair of Hall effect sensors configured to be connected to the second component. The pair of Hall effect sensors are configured to generate basically the same signal changes according to a first relative motion along a first direction between the magnet assembly and the pair of Hall effect sensors, and generate signal changes that are basically equal but opposite to each other according to a second relative motion along a second direction between the magnet assembly and the pair of Hall effect sensors. The first direction is a direction perpendicular to the second direction.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] This application claims priority to a PCT international application filed on June 17, 2021, bearing application number PCT / CN2021 / 100549, the entire contents of which are incorporated herein by reference.

[0002] [Technical field] This application relates to the field of sensing technology, and more particularly to sensing assemblies, force / torque sensor assemblies and robotic joints. [Background technology]

[0003] Hall effect sensors are used to detect motion and position in a variety of applications. Hall effect sensors detect changes in a magnetic field due to deflection of a structure caused by the application of force or torque, and generate an electrical signal that can reflect the force or torque application. Current sensor assemblies use a pair of magnets and a pair of Hall effect sensors located on the same side of the magnets, and such configurations are commonly applied in position encoders. However, the change in magnetic field strength with respect to motion between the Hall effect sensors and the magnets can be nonlinear, affecting the linearity of the overall sensing signal. Summary of the Invention

[0004] One aspect of the present application provides a sensing assembly configured to detect relative motion between a first component and a second component, the sensing assembly including a magnet assembly configured to be connected to the first component and a pair of Hall effect sensors configured to be connected to the second component, the pair of Hall effect sensors configured to generate essentially identical signal changes in response to a first relative motion between the magnet assembly and the pair of Hall effect sensors along a first direction and to generate essentially equal but opposite signal changes in response to a second relative motion between the magnet assembly and the pair of Hall effect sensors along a second direction, the first direction being perpendicular to the second direction.

[0005] Another aspect of the present application is a force / torque sensor assembly configured to detect an applied force or torque, the force / torque sensor assembly including: a body including a first part, a second part, and a deformable part connecting the first part and the second part; and at least one sensing assembly attached to the body and configured to detect relative motion between the first part and the second part. The at least one sensing assembly includes a magnet assembly connected to the first part and a pair of Hall effect sensors connected to the second part. The pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative motion between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative motion between the magnet assembly and the pair of Hall effect sensors along a second direction, the first direction being perpendicular to the second direction.

[0006] Another aspect of the present application provides a robotic joint including a force / torque sensor assembly configured to detect an applied force or torque. The force / torque sensor assembly includes a body including a first part, a second part, and a deformable part connecting the first part and the second part, and at least one sensing assembly attached to the body and configured to detect relative motion between the first part and the second part. The at least one sensing assembly includes a magnet assembly connected to the first part and a pair of Hall effect sensors connected to the second part. The pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative motion between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative motion between the magnet assembly and the pair of Hall effect sensors along a second direction, the first direction being perpendicular to the second direction.

[0007] The details of one or more embodiments of the invention are set forth in the drawings and description which follow. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. [Brief explanation of the drawings]

[0008] Other features of the present application will be more readily understood from the following detailed description of various aspects of the present application, taken in conjunction with the drawings which illustrate various embodiments of the present application. [Figure 1] FIG. 1 is a perspective view of a force / torque sensor assembly according to an embodiment of the present application. [Figure 2] FIG. 2 is a side view of the force / torque sensor assembly shown in FIG. 1. [Figure 3] FIG. 1 illustrates an example of a sensing assembly arrangement for a force / torque sensor assembly according to an embodiment of the present application. [Figure 4] FIG. 1 is a schematic diagram of a force / torque sensor assembly with a sensing assembly attached to a body according to an embodiment of the present application. [Figure 5] FIG. 10 is a schematic diagram of a force / torque sensor assembly with a sensing assembly attached to a body according to another embodiment of the present application. [Figure 6] FIG. 1 is a schematic diagram of a sensing assembly according to an embodiment of the present application. [Figure 7] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 8] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 9] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 10] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 11] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 12] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 13] FIG. 10 is a schematic diagram of a sensing assembly according to another embodiment of the present application. [Figure 14] FIG. 1 is a schematic diagram of a robot according to an embodiment of the present application.

[0009] It should be noted that the drawings in this application are not necessarily drawn to scale. are intended only to depict typical aspects of the present application, and therefore should not be considered as limiting the scope of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. From the following description, it is clear that those skilled in the art can obtain improvements without departing from the spirit of the present invention. It goes without saying that all embodiments obtained by those skilled in the art based on the embodiments of the present application without any creative work are included in the scope of the present application.

[0011] The present disclosure provides a force / torque sensor assembly for detecting an applied force or torque. The force / torque sensor assembly includes a body and at least one sensing assembly. The body includes a first part, a second part, and a deformable part connecting the first part and the second part. At least one sensing assembly is attached to the body for detecting relative motion between the first part and the second part. The at least one sensing assembly includes a magnet assembly connected to the first part and a pair of Hall effect sensors connected to the second part. The pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative motion between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative motion between the magnet assembly and the pair of Hall effect sensors along a second direction. The first direction is perpendicular to the second direction.

[0012] The force / torque sensor assembly according to the present invention will be described in detail below with reference to various embodiments. Fig. 1 is a perspective view of a force / torque sensor assembly 10 according to one embodiment of the present invention. FIG. 2 is a side view of the force / torque sensor assembly 10 shown in FIG. 1. In this embodiment, the force / torque sensor assembly 10 includes a main body 20 and a plurality of sensing assemblies 30 attached to the main body 20. The main body 20 includes a first part 21, a second part 22, and a plurality of deformable parts 23 disposed between the first part 21 and the second part 22 and connecting the first part 21 and the second part 22. The first part 21 and the second part 22 may each be, for example, disk-shaped. When either the first part 21 or the second part 22 is subjected to a force or torque, the deformable parts 23 elastically deform, generating a relative motion (hereinafter referred to as "motion" or "relative motion") between the first part 21 and the second part 22. The sensing assemblies 30 are configured to detect the relative motion between the first part 21 and the second part 22. Based on the detected relative motion and the characteristics of the deformable parts 23, the force or torque applied to the first part 21 or the second part 22 can be determined. For an exemplary basic structure of the force / torque sensor assembly, reference may be made to the applicant's prior patent application (US patent application Ser. No. 16 / 456,562), the contents of which are incorporated herein by reference.

[0013] As shown in FIG. 3 , in one embodiment, multiple sensing assemblies 30 are arranged along the circumferential direction of the force / torque sensor assembly 10. Each sensing assembly 30 includes a magnet assembly 31 connected to the first component 21 and a pair of Hall effect sensors 32 connected to the second component 22. Referring to the exemplary structure shown in FIG. 4 , the magnet assembly 31 is attached to two first mounting legs 210 extending from the first component 21, and the pair of Hall effect sensors 32 are attached to second mounting legs 220 extending from the second component 22. The second mounting legs 220 are positioned between the two first mounting legs 210. In this manner, the sensing assembly 30 may be arranged as shown in FIGS. 6 to 9 . Referring to another exemplary structure shown in FIG. 5 , the magnet assembly 31 is attached to the first mounting leg 210 extending from the first component 21, and each of the pair of Hall effect sensors 32 is attached to two second mounting legs 220 extending from the second component 22. The sensing assembly 30 may be arranged as shown in Figures 10-13, with the first mounting leg 210 positioned between the two second mounting legs 220. According to the embodiment shown in Figures 4-5, the two Hall effect sensors 32 of the sensing assembly 30 are connected to each other by being fixed to the same part (i.e., the second part 22), and thus can move synchronously. Similarly, according to the embodiment shown in Figure 4, the two sets of magnets of the magnet assembly 31 are connected to each other by being fixed to the same part (i.e., the first part 21), and thus can move synchronously.

[0014] It should be understood that the embodiments shown in Figures 1-5 are exemplary only, and that the structure of the force / torque sensor assembly according to the present application may be configured in different ways. For example, in one embodiment, instead of the top-bottom structure shown in Figures 1-3, the first and second components of the force / torque sensor assembly may be inner and outer rings, respectively, arranged in an inner-outer configuration. In one embodiment, the force / torque sensor assembly may include only one set of sensing assemblies that detect force or torque in one direction. In other embodiments, the force / torque sensor assembly may include a different number of sensing assemblies, for example, six or more, to achieve redundant measurements.

[0015] 6 to 13 show the configuration of a sensing assembly 30 according to different embodiments. For convenience of explanation, each illustrated sensing assembly 30 is shown with a corresponding X-axis perpendicular to each other. , and is described in a Cartesian coordinate system having a Y-axis and a Z-axis.

[0016] Those skilled in the art will appreciate that the Hall effect sensor 32 is pre-calibrated, for example, to zero the output of the Hall effect sensor when the force / torque sensor assembly 10 is not subjected to any force or torque.

[0017] In the embodiment shown in FIGS. 6 to 9, a pair of Hall effect sensors are located on opposite sides of the magnet assembly. Referring to the sensing assembly 30a shown in FIG. 6, to detect changes in the magnetic flux component in the Z direction, the sensing directions of the pair of Hall effect sensors 32a are both oriented toward the magnet assembly 31a. That is, the sensing directions of the two Hall effect sensors 32a are opposite to each other. In this embodiment, the magnet assembly 31a includes a magnet whose magnetization direction is perpendicular to the line connecting the pair of Hall effect sensors 32a. With this configuration, relative movement in the X direction between the Hall effect sensor 32a and the magnet assembly 31a applies the same magnetic field change to the pair of Hall effect sensors 32a. Therefore, the pair of Hall effect sensors 32a generate the same signal change in response to relative movement in the X direction between the Hall effect sensor 32a and the magnet assembly 31a. Conversely, relative motion in the Z direction may cause the pair of Hall effect sensors 32a to experience different magnetic field changes, such that one Hall effect sensor 32a detects more magnetic flux in its sensing direction and the other Hall effect sensor 32a detects less magnetic flux in its sensing direction. Thus, relative motion in the Z direction between the Hall effect sensor 32a and the magnet assembly 31a causes the pair of Hall effect sensors 32a to generate essentially equal but opposite signal changes.

[0018] Therefore, when the sensing assembly 30a is configured to detect primarily relative motion in the X direction, an averaging method may be used. Specifically, by adding the signals of the two Hall effect sensors 32a, the sensor signals due to relative motion in the X direction between the Hall effect sensors 32a and the magnet assembly 31a are combined (i.e., twice the signal from one Hall effect sensor), and the sensor signals due to relative motion in the Z direction cancel or reduce each other. This allows for a relatively clear, linear signal that is affected only by relative motion in the X direction. Of course, when the primary relative motion detected by the sensing assembly 30a is in the Z direction, a differential method may be used instead of the averaging method. Specifically, by subtracting the sensor signals, the sensor signals due to relative motion in the Z direction are combined, and the sensor signals due to relative motion in the X direction cancel or reduce each other. Note that although the sensor signals for detecting motion in the Z direction may not be as linear as the signals for detecting motion in the X direction, the sensing assembly 30a can still detect relative motion in the Z direction between the Hall effect sensors 32a and the magnet assembly 31a.

[0019] Referring to the sensing assembly 30b shown in FIG. 7, the two Hall effect sensors 32b also have a sensing direction (i.e., the X direction) perpendicular to the line connecting the two Hall effect sensors 32b to detect changes in magnetic flux components in the X direction. The magnet assembly 31b includes a magnet whose magnetization direction is parallel to the line connecting the pair of Hall effect sensors 32b (e.g., the two magnetic poles of the magnet face the corresponding Hall effect sensors 32b). With this configuration, relative motion between the Hall effect sensor 32b and the magnet assembly 31b in the X direction allows the two Hall effect sensors 32b to sense changes in magnetic flux density in the same direction, even though the magnetic flux directions are opposite to each other. As a result, relative motion in the X direction causes the pair of Hall effect sensors 32b to generate essentially equal but opposite sensor signals. Conversely, relative motion between the Hall effect sensor 32b and the magnet assembly 31b in the Z direction causes the two Hall effect sensors 32b to sense changes in magnetic flux density in the opposite direction to each other, resulting in opposite sensed magnetic flux directions. Thus, relative motion in the Z direction causes the pair of Hall effect sensors 32b to generate sensor signals that are essentially the same.

[0020] Therefore, if the sensing assembly 30b is configured to detect primarily relative motion in the X direction, a differential method may be used. Specifically, by subtracting the sensor signals, the sensor signals due to relative motion in the X direction are combined, and the sensor signals due to relative motion in the Z direction are allowed to cancel or reduce each other. This results in a clean linear signal that is affected only by relative motion in the X direction. If the primary relative motion to be detected is in the Z direction, an averaging method may be used instead. By combining the signals of the two Hall effect sensors 32b, , the sensor signals due to relative motion in the Z direction are combined, and the sensor signals due to relative motion in the X direction cancel or reduce each other.

[0021] In the embodiment shown in Figures 8 and 9, the magnet assembly includes a plurality of magnets arranged in parallel and having alternating, opposite magnetization directions. The magnetization directions of the magnets are all parallel to the line connecting the Hall effect sensors. Referring to the sensing assembly 30c in Figure 8, in order to detect changes in the magnetic flux component in the Z direction, the sensing directions of a pair of Hall effect sensors 32c are both oriented toward the magnet assembly 31c. The magnet assembly 31c includes two magnets with opposite magnetization directions both parallel to the line connecting the pair of Hall effect sensors 32c. (For example, the two magnetic poles of each magnet face the corresponding Hall effect sensor 32c. ) With this configuration, relative motion in the X direction between the Hall effect sensor 32c and the magnet assembly 31c allows the two Hall effect sensors 32c to sense the same change in magnetic flux density, even though the magnetic flux directions are opposite to each other. Thus, relative motion in the X direction causes the pair of Hall effect sensors 32c to generate essentially equal but opposite sensor signals. Conversely, relative motion in the Z direction causes the two Hall effect sensors 32c to sense opposite changes in magnetic flux density, resulting in opposite sensed magnetic flux directions. Therefore, , relative motion in the Z direction causes the pair of Hall effect sensors 32c to generate sensor signals that are essentially identical.

[0022] Therefore, if the sensing assembly 30c is configured to detect primarily relative motion in the X direction, a differential method may be used. Specifically, by subtracting the sensor signals, the sensor signals due to relative motion in the X direction are combined, and the sensor signals due to relative motion in the Z direction are canceled out or reduced by each other. This results in a clean linear signal that is affected only by relative motion in the X direction. If the primary relative motion to be detected is in the Z direction, an averaging method may be used instead. By combining the signals of the two Hall effect sensors 32c, , the sensor signals due to relative motion in the Z direction are combined, and the sensor signals due to relative motion in the X direction cancel or reduce each other.

[0023] As shown in FIG. 9, sensing assembly 30d differs from sensing assembly 30c in that magnet assembly 31d includes three magnets with alternating opposite magnetization directions, and a pair of Hall effect sensors 32d detects changes in magnetic flux components in the X direction by detecting the direction perpendicular to the line connecting the pair of Hall effect sensors 32d (i.e., the X direction). The operation of sensing assembly 32d is similar to that of sensing assembly 32c in FIG. 8. That is, relative motion in the X direction between Hall effect sensor 32d and magnet assembly 31d causes the two Hall effect sensors 32d to generate essentially equal but opposite signals, and relative motion in the Z direction causes the two Hall effect sensors 32d to generate essentially identical signals. This allows for similar detection of major relative motion in the X or Z direction using an appropriate algorithm.

[0024] It should be appreciated that using more magnets with alternating magnetization directions can similarly detect primary relative motion and eliminate interference from relative motion in other directions, with the distinction being that more magnets can provide a stronger magnetic field and potentially result in different linearity between relative motion and sensor signal.

[0025] It should also be noted that in all of the embodiments shown above, the sensing directions of the Hall effect sensors and the magnet arrangement direction may be different, as long as the two Hall effect sensors generate essentially the same signal in response to a first relative motion between the Hall effect sensors and the magnet assembly, and generate essentially equal but opposite signals in response to a second relative motion between the Hall effect sensors and the magnet assembly that is perpendicular to the first relative motion. For example, in other embodiments, the sensing direction of the Hall effect sensor 32a in FIG. 6 may be changed to point in the positive or negative X direction. In such a configuration, the two Hall effect sensors 32a Similarly, relative motion between the Hall effect sensor 32a and the magnet assembly 31a in the X direction can produce essentially the same signal, and relative motion between the Hall effect sensor 32a and the magnet assembly 31a in the Z direction can produce essentially equal but opposite signals. Such a configuration is feasible, although it may increase the nonlinearity of the sensor to some extent.

[0026] In some other embodiments, the relative positions of the magnet and the Hall effect sensor 32 may be interchanged. Referring to the embodiment shown in Figures 10-13, the magnet assembly includes a first magnet group and a second magnet group, and a pair of Hall effect sensors are located between the first magnet group and the second magnet group. The first magnet group and the second magnet group are connected to each other (e.g., fixed to the same support structure) to allow the two magnet groups to move together.

[0027] Referring to the sensing assembly 30e shown in FIG. 10, the sensing directions of a pair of Hall effect sensors 32e are oriented toward two sets of magnets 310e and 311e to detect magnetic flux components in the Z direction. The first magnet group 310e and the second magnet group 311e each include a magnet with the same magnetization direction, which is perpendicular to the line connecting the pair of Hall effect sensors 32e. With this configuration, relative motion in the X direction causes the pair of Hall effect sensors 32e to detect the same magnetic flux change and generate the same signal change. Due to relative motion in the Z direction, one Hall effect sensor 32e detects more magnetic flux in its sensing direction and the other Hall effect sensor 32e detects less magnetic flux in its sensing direction, so the pair of Hall effect sensors 32e generate essentially equal but opposite signal changes. Therefore, when the sensing assembly 30e is configured to detect primary relative motion in the X direction, an averaging method can be used to obtain a clear linear signal that is affected only by relative motion in the X direction. Alternatively, a differential method may be used when configured to detect predominantly relative motion in the Z direction.

[0028] Referring to the sensing assembly 30f shown in FIG. 11, the pair of Hall effect sensors 32f have a sensing direction perpendicular to the line connecting the two Hall effect sensors 32f (i.e., the X direction) to detect magnetic flux components in the X direction. The first magnet group 310f and the second magnet group 311f each include a magnet with a magnetization direction parallel to the line connecting the pair of Hall effect sensors 32g. With this configuration, relative motion in the X direction causes the pair of Hall effect sensors 32f to sense the same change in magnetic flux density, even though their magnetic flux directions are opposite to each other. Therefore, relative motion in the X direction causes the pair of Hall effect sensors 32f to generate essentially equal but opposite signal changes. Conversely, relative motion in the Z direction causes the two Hall effect sensors 32f to sense opposite changes in magnetic flux density, resulting in opposite sensed magnetic flux directions. Therefore, relative motion in the Z direction causes the pair of Hall effect sensors 32f to generate essentially the same signal changes. Thus, if the sensing assembly 30g is configured to detect primarily relative motion in the X direction, a differential method can be used to obtain a clean linear signal that is affected only by relative motion in the X direction, and if relative motion in the Z direction is to be detected, an averaging method may be used instead.

[0029] 12 and 13, the first magnet group and the second magnet group each include a plurality of magnets arranged in parallel and having magnetization directions that are alternately opposite to each other parallel to a line connecting the pair of Hall effect sensors, and any two magnets located on the same line (i.e., in the Z direction) parallel to the line connecting the two Hall effect sensors have the same magnetization direction.

[0030] Referring to the sensing assembly 30g in FIG. 12, the first magnet group 310g and the second magnet group 311g each include two magnets arranged in parallel with each other and having alternating, opposite magnetization directions. The sensing directions of the pair of Hall effect sensors 32g are oriented toward the first magnet group 310g and the second magnet group 311g, respectively, to detect changes in magnetic flux components in the Z direction. With this configuration, relative motion in the X direction generates essentially equal but opposite signal changes because the pair of Hall effect sensors 32g sense the same changes in magnetic flux density despite having opposite magnetic flux directions. Conversely, relative motion in the Z direction causes the two Hall effect sensors 32g to sense opposite changes in magnetic flux density, and because the sensed magnetic flux directions are opposite, the two Hall effect sensors 32g generate essentially the same signal changes. This allows for a difference method to be used to obtain a clean linear signal that is affected only by relative motion in the X direction, when the sensing assembly 30g is configured to detect relative motion primarily in the X direction. ,When detecting relative motion in the Z direction, an averaging method may be used instead.

[0031] Referring to the sensing assembly 30h in FIG. 13, the first magnet group 310h and the second magnet group 311h each have three magnets arranged in parallel with each other and with alternating, opposite magnetization directions. A pair of Hall effect sensors 32h have sensing directions perpendicular to the line connecting the two Hall effect sensors 32h (i.e., in the X direction) to detect magnetic flux components in the X direction. The operation of the sensing assembly 30h is similar to that of the embodiment in FIG. 12: relative motion in the X direction causes the two Hall effect sensors 32h to generate essentially equal but opposite signal changes, and relative motion in the Z direction causes the two Hall effect sensors 32h to generate essentially identical signal changes. Therefore, by using an appropriate algorithm, it is possible to detect predominant motion in the X or Z direction.

[0032] It should be understood that in the configurations of Figures 12-13, using more magnets with alternating magnetization directions would similarly allow detection of primary relative motion while eliminating interference from relative motion in other directions, with the distinction being that more magnets would , can provide a stronger magnetic field and may result in a different linearity between relative motion and sensor signal.

[0033] As with the embodiments shown in FIGS. 6-9 , in all of the embodiments shown in FIGS. 10-13 , the sensing directions of the Hall effect sensors and the magnet arrangement may be different, as long as the two Hall effect sensors generate essentially identical signals in response to a first relative motion between the Hall effect sensors and the magnet assembly and generate essentially equal but opposite signals in response to a second relative motion perpendicular to the first relative motion between the Hall effect sensors and the magnet assembly. For example, in another embodiment of the sensing assembly shown in FIG. 10 , the sensing directions of the pair of Hall effect sensors may be changed to point in either the positive or negative X direction. In such a configuration, the two Hall effect sensors similarly generate essentially identical signals in response to relative motion between the Hall effect sensors and the magnet assembly in the X direction and essentially equal but opposite signals in response to relative motion between the Hall effect sensors and the magnet assembly in the Z direction. While such a configuration may increase the nonlinearity of the sensors to some extent, it is feasible.

[0034] In the embodiments shown in FIGS. 6 to 13, the two sensors are arranged symmetrically, and the line connecting them is perpendicular or parallel to the detection direction of the sensor or the magnetization direction of the magnet. However, it should be understood that in practice, the positions of the two sensors may be slightly misaligned, i.e., the line connecting the two sensors may be approximately perpendicular or approximately parallel to the detection direction or magnetization direction.

[0035] In the configurations of the above sensing assemblies 30a to 30h, if the Hall effect sensors 32a to 32h are not close to the edges of the magnets, the edge effect of the magnets in the Y direction can be ignored, and therefore the magnet-sensor signal characteristics in the Y direction are considered to be constant.

[0036] According to each of the above embodiments, the sensing assembly 30 further includes a magnetically conductive assembly 33 for aligning the magnetic field of the magnet assembly 31. The magnetically conductive assembly 33 may include a magnetically conductive material, such as a metal or alloy with high magnetic permeability, such as cast iron, silicon steel, nickel-zinc ferrite, nickel-iron alloy, or manganese-zinc ferrite. In one specific embodiment, the material of the magnetically conductive assembly 33 is carbon steel. The magnetically conductive material may be, for example, , may be located on either side of the magnet and on either side of a pair of Hall effect sensors 32 .

[0037] According to each of the above embodiments, the sensing assemblies 30a-30h use pairs of Hall effect sensors 32a-32h to detect motion in multiple directions. In other embodiments, more pairs of sensors may be used to more accurately measure the load applied to the force / torque sensor assembly 10.

[0038] Multiple Hall effect sensors can provide cross-checking and cross-monitoring between multiple sensor signals, especially when motion in a nonlinear direction is not the dominant motion. Cross-checking and cross-monitoring can provide additional operational safety by allowing early determination of damage or failure of one or more sensors or magnets. Multiple sensors may also be used to suppress common-mode noise, especially Gaussian electrical noise.

[0039] 3, the multiple sensing assemblies 30 are arranged circumferentially around the force / torque sensor assembly 10. In other embodiments, the sensing assemblies 30 may be arranged in other ways, for example, the sensing assemblies 30 may be randomly positioned between the first part 21 and the second part 22.

[0040] The multiple sensing assemblies 30 may have the same configuration, such as any one of the sensing assemblies 30a-30h shown in FIGS. 6-13. The multiple sensing assemblies 30 may each have a different configuration, such as a selection from the sensing assemblies 30a-30h. The multiple sensing assemblies 30 can simultaneously measure the force or torque applied to the force / torque sensor assembly 10, thereby allowing the outputs of these sensing assemblies 30 to be combined to obtain more accurate results. In one specific embodiment, for example, two sensing assemblies 30 are configured so that, in response to the same force and torque, each pair of Hall effect sensors generates essentially the same signal change or essentially equal but opposite signal changes. In another specific embodiment, one sensing assembly 30 is configured so that, in response to the same force and torque, each pair of Hall effect sensors generates essentially the same signal change, and the other sensing assembly 30 is configured so that each pair of Hall effect sensors generates essentially equal but opposite signal changes. The two sensing assemblies 30 can be arranged in any manner to simultaneously measure the same force or torque.

[0041] Furthermore, by disposing sensing assemblies 30 at different locations on the force / torque sensor assembly 10, it is possible to detect relative displacement at different locations between the first component 21 and the second component 22. Also, by mounting multiple sensing assemblies 30 at different locations, it is possible to account for the deflection of the force / torque sensor assembly 10 as a whole, thereby determining the overall external force or torque based on the stiffness of the force / torque sensor assembly 10. For example, detecting displacement at different locations is particularly useful when detecting shear forces, since shear forces generate different displacements at different locations.

[0042] In one embodiment, multiple sensing assemblies 30 may have different spatial orientations, regardless of whether they have the same configuration. For example, multiple sensing assemblies 30 using any of the configurations shown in FIGS. 6-13 may be arranged on the body 20 so that their primary sensing directions (e.g., the X direction) are aligned with the axial, radial, and shear directions of the sensor assembly 10, respectively. This configuration allows the force / torque sensor assembly 10 to detect forces or torques in multiple directions. For example, a force applied perpendicular to the force / torque sensor assembly 10 may cause a portion of the sensing assembly 30 to move relative to the X direction. Therefore, this portion of the sensing assembly 30 is suitable for measuring the perpendicular force because it can generate a linear sensor signal. However, when a torque is applied around the axis of the force / torque sensor assembly 10, the torque may cause the corresponding portion of the sensing assembly 30 to move substantially relative to the Y direction, making the corresponding portion of the sensing assembly 30 inappropriate for detecting the torque. In this case, a sensing assembly 30 is required that translates torque into motion in the X direction, and the sensing assembly 30 may be oriented, for example, at 90 degrees relative to the sensing assembly 30 in the portion above.

[0043] It should be understood that the sensing direction of the Hall effect sensor 32 can be changed in each configuration. For example, in the embodiment shown in Figure 6, the sensing direction of the Hall effect sensor 32 may be changed to be parallel to the magnetization direction of the magnet assembly 31. If the sensing direction of the Hall effect sensor 32 is changed, this may affect linearity.

[0044] It should be understood that the sensing assembly of the present application is not limited to detecting forces or torques as described above, but may be used in a variety of other applications where movement or displacement needs to be detected.

[0045] It should be noted that in this application, the terms "same" or "equal" used to describe changes in sensor signal or changes in magnetic flux do not mean that the changes in signal or magnetic flux are completely the same or completely equal, and there may be some deviation due to the distribution of magnetic flux, etc. Furthermore, it should be noted that the terms "linear" and "linearity" used to describe the relationship between a sensor signal and movement do not mean that the change in signal relative to movement is completely linear.

[0046] The present invention further provides a robot and a robot joint for use in the robot. The robot joint includes a force / torque sensor assembly 10 according to any of the embodiments described above.

[0047] 14 exemplarily shows a robot 100 including arms 101 and robot joints 102 connecting adjacent arms 101. The robot joints 102 have force / torque sensor assemblies, and first and second parts of the force / torque sensor assemblies may be connected to, for example, two adjacent arms 101, respectively.

[0048] The purpose of the terminology used herein is to describe specific embodiments only. As used herein, the singular forms "one" and "one" are used interchangeably. " and "including" are intended to include the plural forms unless the context clearly indicates otherwise. The term "comprising" when used herein includes any of said features, steps, operations, elements and / or part is meant to be present, but one or more other features, steps, operations It should be understood that the term "optional" or "optionally" does not exclude the presence of any element, component, and / or combination thereof. "Optional" or "optionally" means that the subsequently described event or circumstance is possible, but not required, and that the description includes cases where the event or circumstance occurs and cases where the event or circumstance does not occur.

[0049] As used throughout this specification and claims, approximation terms can be applied to modify any quantitative expression that can be permissibly varied without resulting in a change in the basic function involved. Thus, values ​​modified by one or more terms such as "about," "approximately," and "substantially" are not limited to the exact value specified. In at least some instances, approximation terms may correspond to the precision of an instrument for measuring the value. Herein and throughout this specification and claims, range limitations are combinable and / or interchangeable, and unless the context and language dictate otherwise, such ranges are specified and include all subranges encompassed therein.

[0050] The corresponding structure, material, act, and equivalents of all apparatus or step and functional elements within the scope of the appended claims are intended to include any structure, material, or act for performing the function in combination with other specifically claimed elements. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope of the invention. The embodiments were chosen and described to best explain the principles and practical applications of the invention and to enable others skilled in the art to understand the invention in terms of various embodiments with various modifications to suit the particular uses contemplated.

Claims

1. a sensing assembly configured to detect relative motion between a first part and a second part, a magnet assembly configured to be connected to the first component; a pair of Hall effect sensors configured to be connected to the second component; the pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative movement between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative movement between the magnet assembly and the pair of Hall effect sensors along a second direction perpendicular to the first direction; A sensing assembly, wherein the pair of Hall effect sensors are respectively located on opposite sides of the magnet assembly, the magnet assembly including at least two magnets arranged in parallel and having alternating opposite magnetization directions, the magnetization directions of the magnets being parallel to a line connecting the pair of Hall effect sensors.

2. The sensing assembly of claim 1 , wherein the pair of Hall effect sensors each have a sensing direction facing the magnet assembly or have the same sensing direction perpendicular to a line connecting the pair of Hall effect sensors.

3. The sensing assembly of claim 1 , further comprising a magnetically conductive assembly configured to align the magnetic field of the magnet assembly.

4. 1. A force / torque sensor assembly configured to detect an applied force or torque, comprising: a body including a first part, a second part, and a deformable part connecting the first part and the second part; at least one sensing assembly attached to the body and configured to detect relative motion between the first and second components, the sensing assembly including a magnet assembly connected to the first component and a pair of Hall effect sensors connected to the second component; the pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative movement between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative movement between the magnet assembly and the pair of Hall effect sensors along a second direction perpendicular to the first direction; a pair of Hall effect sensors located on opposite sides of the magnet assembly, the magnet assembly including at least two magnets arranged in parallel and having alternating opposite magnetization directions, the magnetization directions of the magnets being parallel to a line connecting the pair of Hall effect sensors.

5. 5. The force / torque sensor assembly of claim 4, wherein the at least one sensing assembly includes two sensing assemblies disposed in the force / torque sensor assembly, the two sensing assemblies configured such that each of the pair of Hall effect sensors generates essentially the same or essentially equal but opposite signal changes in response to the same force or torque applied to the force / torque sensor assembly.

6. 5. The force / torque sensor assembly of claim 4, wherein the at least one sensing assembly includes two sensing assemblies disposed in the force / torque sensor assembly, the two sensing assemblies configured such that, in response to a same force or torque applied to the force / torque sensor assembly, the pair of Hall effect sensors of one sensing assembly generate essentially the same signal change and the pair of Hall effect sensors of the other sensing assembly generate essentially equal but opposite signal changes.

7. 5. The force / torque sensor assembly of claim 4, wherein the at least one sensing assembly includes two sensing assemblies disposed on the force / torque sensor assembly, the two sensing assemblies each configured to detect relative motion between the first part and the second part at a different position.

8. 1. A robotic joint comprising a force / torque sensor assembly configured to detect an applied force or torque, The force / torque sensor assembly comprises: a body including a first part, a second part, and a deformable part connecting the first part and the second part; at least one sensing assembly attached to the body and configured to detect relative motion between the first and second components, the sensing assembly including a magnet assembly connected to the first component and a pair of Hall effect sensors connected to the second component; the pair of Hall effect sensors are configured to generate essentially identical signal changes in response to a first relative movement between the magnet assembly and the pair of Hall effect sensors along a first direction, and to generate essentially equal but opposite signal changes in response to a second relative movement between the magnet assembly and the pair of Hall effect sensors along a second direction perpendicular to the first direction; a pair of Hall effect sensors located on opposite sides of the magnet assembly, the magnet assembly including at least two magnets arranged in parallel and having alternating opposite magnetization directions, the magnetization directions of the magnets being parallel to a line connecting the pair of Hall effect sensors.

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