Force-torque sensor and robot

Abstract

The present embodiment relates to a force-torque sensor comprising: a fixed part; a moving part disposed on the fixed part; a substrate disposed on the fixed part and including an electrode; and a ground plate of which at least a portion moves integrally with the moving part, wherein the ground plate includes a shape for sensing the temperature of the ground plate.

Description

Force-torque sensors and robots

[0001] The present embodiment relates to a force-torque sensor and a robot.

[0002] Robots are used in a variety of fields, including industry, medicine, service, and other fields, and their scope of application is constantly expanding. To improve the performance and ensure safety of robotic systems, accurate monitoring and control of robot movements are essential. In particular, the forces and torques generated when a robot interacts with its environment or handles objects are crucial information.

[0003] Conventional robot sensor technology has primarily focused on detecting motion states such as position, velocity, and acceleration. However, forces and torques play a crucial role in providing information about robot interactions and the working environment. Force-torque sensors are essential for robots to safely grasp and manipulate objects and respond to their environment. Furthermore, these sensors can be utilized to improve robot efficiency and prevent malfunctions.

[0004] Conventional force-torque sensors cannot separate the applied external force into the forces along each axis. Therefore, they receive input simultaneously and decompose the forces. This leads to the problem of crosstalk noise being mixed into the detection values ​​for each axis. In particular, noise increases when the Z-axis force and torque force are mixed.

[0005] (Patent Document 1) KR 10-2023-0123723 A

[0006] The present embodiment seeks to provide a force-torque sensor capable of measuring z-axis force and torque force separately.

[0007] Through this, we aim to improve robot control and work processes.

[0008] Furthermore, it is intended to provide a force-torque sensor in which a sensing unit for measuring the amount of movement of a moving part is formed of a capacitor type.

[0009] In addition, it is intended to provide a force-torque sensor that maintains precise detection capability even when temperature changes occur inside the sensor.

[0010] A force-torque sensor according to the present embodiment includes a fixed part; a moving part disposed on the fixed part; a substrate disposed on the fixed part and including an electrode; and a ground plate at least a portion of which moves integrally with the moving part, wherein the ground plate may include a shape for detecting a temperature of the ground plate.

[0011] The above ground plate may include a wing portion facing the electrode of the substrate, and a tail portion extending from the wing portion with a width smaller than the wing portion.

[0012] The above tail portion can be formed as a single strand having a shape that is folded multiple times.

[0013] One end of the above tail portion may be connected to the wing portion, and the other end of the above tail portion may be formed as a free end.

[0014] Both one end of the above tail portion and the other end of the above tail portion can be connected to the above wing portion.

[0015] The wing portion of the ground plate may overlap with the electrode of the substrate in the z-axis direction, a part of the tail portion of the ground plate may overlap with the electrode of the substrate in the z-axis direction, and another part of the tail portion of the ground plate may not overlap with the electrode of the substrate in the z-axis direction.

[0016] The electrode of the substrate may include a first portion disposed on an upper surface of the substrate and a second portion disposed on a side surface of the substrate, the wing portion of the ground plate may face the first portion of the electrode, and the ground plate may include a protrusion that is bent and extends from the wing portion and faces the second portion of the electrode.

[0017] The above tail portion and the above protrusion may be formed on different sides of the wing portion.

[0018] The substrate includes a ground terminal, and the ground plate includes a first coupling portion coupled to the moving portion, a second coupling portion coupled to the ground terminal of the substrate, and a connecting portion connecting the first coupling portion and the second coupling portion, and the connecting portion may include a plurality of holes formed between the first coupling portion and the second coupling portion.

[0019] The above force-torque sensor may include a coating layer disposed on the surface of the tail portion.

[0020] The above ground plate includes a plurality of ground plates, and at least one of the plurality of ground plates may have a different shape from the other ground plates.

[0021] The above moving part includes an inner carrier and an outer carrier disposed between the fixed part and the inner carrier, a first ball may be disposed between the inner carrier and the outer carrier, and a second ball may be disposed between the fixed part and the outer carrier.

[0022] The inner carrier moves in a yaw direction, which is a rotational direction centered around the x-axis, a pitch direction, which is a rotational direction centered around the y-axis, and a roll direction, which is a rotational direction centered around the z-axis, relative to the outer carrier, and the outer carrier can move together with the inner carrier when the inner carrier moves in the z-axis direction.

[0023] The force-torque sensor may include an elastic member coupled to the inner carrier and the outer carrier.

[0024] The robot according to the present embodiment may include the force-torque sensor.

[0025] The force-torque sensor according to this embodiment can measure Z-axis force and torque force separately. This minimizes the influence of noise due to crosstalk on the detection values ​​for each axis. In other words, the measurement accuracy of the force-torque sensor can be improved.

[0026] Furthermore, the size of the force-torque sensor can be miniaturized through the capacitor type sensing unit.

[0027] Furthermore, precise detection capabilities can be maintained even when temperature changes occur within the sensor. This allows for a force-torque sensor that can be used in extreme low and high temperatures.

[0028] Figure 1 is a perspective view of a force-torque sensor according to the present embodiment.

[0029] Figure 2 is a cross-sectional view taken along line AA of Figure 1.

[0030] FIG. 3 is a cross-sectional view of a force-torque sensor according to the present embodiment, cut perpendicular to the z-axis and viewed from above.

[0031] Figure 4 is an exploded perspective view of a force-torque sensor according to the present embodiment.

[0032] FIG. 5 is an exploded perspective view of the force-torque sensor according to the present embodiment viewed from a different direction than FIG. 4.

[0033] Fig. 6 is a perspective view of Fig. 1 with the lead and related components omitted.

[0034] Fig. 7 is a perspective view of Fig. 6 with the upper cover and related components omitted.

[0035] Fig. 8 is a perspective view of Fig. 7 with the base and elastic member omitted.

[0036] Fig. 9 is a perspective view of Fig. 8 with the external carrier and related components omitted.

[0037] Fig. 10 is a perspective view of Fig. 9 with the internal carrier and related components omitted.

[0038] Fig. 11a is a perspective view of a sensing unit of a force-torque sensor according to the present embodiment.

[0039] Fig. 11b is a perspective view of the substrate of the force-torque sensor according to the present embodiment.

[0040] Fig. 12 is a perspective view showing the tail portion and related configuration of the force-torque sensor according to the present embodiment.

[0041] FIG. 13 is a plan view and an enlarged view showing the tail portion and related configuration of a force-torque sensor according to the present embodiment.

[0042] Fig. 14 is a bottom perspective view of a force-torque sensor according to the present embodiment.

[0043] Fig. 15 is a bottom perspective view of Fig. 14 with the lower cover and related components omitted.

[0044] Fig. 16 is a bottom perspective view and a partially enlarged view of Fig. 15 with the substrate omitted.

[0045] Figure 17 is a bottom perspective view of Figure 16 with the ground plate omitted.

[0046] Fig. 18 is a bottom perspective view of Fig. 16 with the base omitted.

[0047] Fig. 19 is a bottom perspective view of Fig. 18 with the external carrier and related components omitted.

[0048] Fig. 20 is a drawing for explaining a case where an external force having a component in the yaw direction or pitch direction is applied to a force-torque sensor according to the present embodiment.

[0049] Fig. 21 is a drawing for explaining changes when an external force having a roll direction component is applied to a force-torque sensor according to the present embodiment.

[0050] Fig. 22 is a drawing for explaining a case where an external force having a component in the z-axis direction is applied to a force-torque sensor according to the present embodiment.

[0051] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0052] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0053] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0054] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0055] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0056] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and are not intended to limit the nature, order, or sequence of the components.

[0057] And, when a component is described as being 'connected', 'coupled', or 'connected' to another component, it may include not only cases where the component is 'connected', 'coupled', or 'connected' directly to the other component, but also cases where the component is 'connected', 'coupled', or 'connected' by another component between the component and the other component.

[0058] Additionally, when described as being formed or arranged "above" or "below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below," the meaning may include not only the upward direction but also the downward direction based on one component.

[0059] Hereinafter, one of the “internal carrier (210)” and the “external carrier (220)” may be referred to as the “first carrier” and the other may be referred to as the “second carrier”.

[0060] Hereinafter, one of the “upper coupling member (610)”, the “lower coupling member (620)”, and the “outer coupling member (630)” may be referred to as the “first coupling member”, the other may be referred to as the “second coupling member”, and the other may be referred to as the “third coupling member”. In addition, each of the “upper coupling member (610)”, the “lower coupling member (620)”, and the “outer coupling member (630)” may be referred to as a “coupling member”.

[0061] Hereinafter, “the first ball (510)” and “the second ball (520)” may each be referred to as “balls.”

[0062] Hereinafter, one of the z-axis, x-axis, and y-axis may be referred to as the “first axis,” the other as the “second axis,” and the other as the “third axis.”

[0063] Hereinafter, one of the roll direction, yaw direction, and pitch direction may be referred to as a “first circumferential direction,” another may be referred to as a “second circumferential direction,” and another may be referred to as a “third circumferential direction.” Alternatively, the roll direction, yaw direction, and pitch direction may be referred to as “first to third directions.”

[0064]

[0065] Below, the configuration of the force-torque sensor according to the present embodiment is described with reference to the drawings.

[0066] Fig. 1 is a perspective view of a force-torque sensor according to the present embodiment. Fig. 2 is a cross-sectional view taken along line AA of Fig. 1. Fig. 3 is a cross-sectional view of the force-torque sensor according to the present embodiment taken along a line perpendicular to the z-axis and viewed from above. Fig. 4 is an exploded perspective view of the force-torque sensor according to the present embodiment. Fig. 5 is an exploded perspective view of the force-torque sensor according to the present embodiment viewed from a different direction from Fig. 4. Fig. 6 is a perspective view of Fig. 1 with the leads and related components omitted. Fig. 7 is a perspective view of Fig. 6 with the upper cover and related components omitted. Fig. 8 is a perspective view of Fig. 7 with the base and elastic member omitted. Fig. 9 is a perspective view of Fig. 8 with the external carrier and related components omitted. Fig. 10 is a perspective view of Fig. 9 with the internal carrier and related components omitted. Fig. 11a is a perspective view of a sensing unit of the force-torque sensor according to the present embodiment. Fig. 11b is a perspective view of a substrate of a force-torque sensor according to the present embodiment. Fig. 12 is a perspective view illustrating a tail portion and related components of a force-torque sensor according to the present embodiment. Fig. 13 is a plan view and an enlarged view illustrating a tail portion and related components of a force-torque sensor according to the present embodiment. Fig. 14 is a bottom perspective view of a force-torque sensor according to the present embodiment. Fig. 15 is a bottom perspective view of Fig. 14 with the lower cover and related components omitted. Fig. 16 is a bottom perspective view and a partially enlarged view of Fig. 15 with the substrate omitted. Fig. 17 is a bottom perspective view of Fig. 16 with the ground plate omitted. Fig. 18 is a bottom perspective view of Fig. 16 with the base omitted. Fig. 19 is a bottom perspective view of Fig. 18 with the external carrier and related components omitted.

[0067] A force-torque sensor can be used to detect and measure forces and torques applied to a robot in real time. A force-torque sensor can detect a force applied to the force-torque sensor. A force-torque sensor can measure a force applied to the force-torque sensor. A force-torque sensor can detect a torque applied to the force-torque sensor. A force-torque sensor can measure a torque applied to the force-torque sensor. A force-torque sensor can be a six-axis force-torque sensor. A force-torque sensor can detect and measure forces in six directions, namely the x-axis, y-axis, z-axis, yaw, pitch, and roll directions. A force-torque sensor can be a finger sensor of a robot.

[0068] The force-torque sensor may include a fixed part (100). The fixed part (100) is a concept distinct from the moving part (200) and may be a part that is relatively fixed when the moving part (200) moves.

[0069] The force-torque sensor may include a base (110). The fixing member (100) may include the base (110). The base (110) may be disposed on the lower cover (130). The base (110) may be disposed on the lower cover (130). The base (110) may be disposed on the upper cover (120). The base (110) may be disposed under the upper cover (120). The base (110) may be disposed between the lower cover (130) and the upper cover (120). The base (110) may accommodate an outer carrier (220) therein. The base (110) may accommodate an inner carrier (210) therein. The base (110) may be disposed on the outside of the outer carrier (220). The base (110) may be disposed on the outside of the inner carrier (210).

[0070] The base (110) may include a groove (111). The groove (111) may be a ball rail. A second ball (520) may be placed in the groove (111). The groove (111) may extend in the z-axis direction. The second ball (520) may move along the groove (111) of the base (110). The second ball (520) may roll along the groove (111) of the base (110).

[0071] The base (110) may include a groove (112). The groove (112) may be formed on the inner surface of the fixing portion (100). The groove (112) may be formed on the inner surface of the base (110). The groove (112) may be formed concavely on the inner surface of the fixing portion (100). The groove (112) may be formed concavely on the inner surface of the base (110). A protrusion (225) of an external carrier (220) may be arranged in the groove (112) of the fixing portion (100).

[0072] In this embodiment, the rotation of the external carrier (220) with respect to the base (110) can be prevented through the shape of the fit between the groove (112) of the base (110) and the protrusion (225) of the external carrier (220). When the external carrier (220) rotates around the z-axis with respect to the fixed part (100), the protrusion (225) of the external carrier (220) can come into contact with the groove (112) of the fixed part (100).

[0073] The force-torque sensor may include an upper cover (120). The fixing member (100) may include the upper cover (120). The upper cover (120) may be disposed on the base (110). The upper cover (120) may be disposed on the base (110). The upper cover (120) may be coupled to the base (110). The upper cover (120) may be coupled to an upper surface of the base (110). The upper cover (120) may be fixed to the base (110). The upper cover (120) may be disposed between the base (110) and the lid (230).

[0074] The force-torque sensor may include a lower cover (130). The fixing member (100) may include the lower cover (130). The lower cover (130) may form a bottom portion of the force-torque sensor. The lower cover (130) may be positioned opposite the lead (230). The lower cover (130) may be positioned below the base (110). The lower cover (130) may be coupled to a lower surface of the base (110). The lower cover (130) may be coupled to the base (110). The lower cover (130) may include a groove through which the substrate (140) passes.

[0075] The force-torque sensor may include a moving part (200). The moving part (200) may be disposed within the fixed part (100). The moving part (200) may be disposed on the fixed part (100). The moving part (200) may move relative to the fixed part (100). When an external force is applied, the moving part (200) may move relative to the fixed part (100). At least a portion of the moving part (200) may be disposed within the fixed part (100). A portion of the moving part (200) may be exposed outside the fixed part (100). The moving part (200) may be disposed on the lower cover (130).

[0076] The force-torque sensor may include an inner carrier (210). The moving part (200) may include the inner carrier (210). The inner carrier (210) may be disposed within the fixed part (100). The inner carrier (210) may be disposed within the outer carrier (220). The inner carrier (210) may be disposed on the fixed part (100). The inner carrier (210) may be disposed within the base (110). The inner carrier (210) may include a curved surface. A first ball (510) may be disposed on the curved surface of the inner carrier (210). The inner carrier (210) may be formed in a spherical shape at least in a portion. The inner carrier (210) may be formed in a spherical shape at least in a portion so that the center of rotation does not change and remains constant. Through this, the inner carrier (210) moves as intended by the designer, so that the occurrence of crosstalk can be minimized.

[0077] The inner carrier (210) can move in the yaw direction, which is a rotational direction centered around the x-axis, the pitch direction, which is a rotational direction centered around the y-axis, and the roll direction, which is a rotational direction centered around the z-axis, with respect to the outer carrier (220). The x-axis, the y-axis, and the z-axis can be orthogonal to each other.

[0078] The inner carrier (210) and the outer carrier (220) can move integrally in the z-axis direction with respect to the fixed part (100).

[0079] The inner carrier (210) may include an electrode (211). The electrode (211) may be disposed on the surface of the inner carrier (210). The electrode (211) may be disposed on the lower surface of the inner carrier (210). The electrode (211) may be disposed on the outer surface of the inner carrier (210). The electrode (211) may be disposed on the outer circumferential surface of the inner carrier (210). The electrode (211) may be connected to the ground plate (320). The electrode (211) may be directly connected to the ground plate (320). The electrode (211) may be electrically connected to the ground plate (320). The electrode (211) may be a metal pattern. The electrode (211) may be formed by plating a metal pattern on the surface of the inner carrier (210), which is an injection-molded product.

[0080] Compared to the case where only the ground plate (320) is present, when the electrode (211) of the internal carrier (210) is additionally formed, the electrostatic capacitance measured at the electrode (311) of the substrate (310) can increase. In this case, even when the electrostatic capacitance decreases due to movement of the internal carrier (210) and the ground plate (320), the measurement of the electrostatic capacitance can be facilitated.

[0081] The electrode (211) may include a plurality of electrodes. The electrode (211) may include four electrodes. The electrode (211) may include first to fourth electrodes. The electrode (211) may include first to fourth electrodes corresponding to the first to fourth electrodes (311-1, 311-2, 311-3, 311-4).

[0082] The inner carrier (210) may include a protrusion (212). The protrusion (212) may be formed on the lower surface of the inner carrier (210). The protrusion (212) may protrude downward from the inner carrier (210). The protrusion (212) may protrude from the lower surface of the inner carrier (210). A ground plate (320) may be coupled to the protrusion (212). A ground plate (320) may be coupled to the lower surface of the protrusion (212). The ground plate (320) may be adhered to the protrusion (212).

[0083] The inner carrier (210) may include a protrusion (213). The protrusion (213) may be a stopper. The protrusion (213) may be formed on the outer surface of the inner carrier (210). The protrusion (213) may protrude outward from the inner carrier (210). The protrusion (213) may be arranged in a groove (224) of the outer carrier (220).

[0084] The force-torque sensor may include an outer carrier (220). The moving part (200) may include the outer carrier (220). The outer carrier (220) may be disposed between the inner carrier (210) and the fixed part (100). The outer carrier (220) may be disposed on the outside of the inner carrier (210). The outer carrier (220) may be disposed within the fixed part (100). The outer carrier (220) may be disposed on the fixed part (100). The outer carrier (220) may be disposed within the base (110). The outer carrier (220) may move in the z-axis direction with respect to the fixed part (100). The outer carrier (220) may move together with the inner carrier (210) when the inner carrier (210) moves in the z-axis direction.

[0085] The outer carrier (220) may include an electrode (221). The electrode (221) may be disposed on the surface of the outer carrier (220). The electrode (221) may be disposed on the lower surface of the outer carrier (220). The electrode (221) may be disposed on the inner peripheral surface of the outer carrier (220). The electrode (221) may be disposed on the outer surface of the outer carrier (220). The electrode (221) may be a metal pattern. The electrode (221) may be formed by plating a metal pattern on the surface of the outer carrier (220), which is an injection-molded product.

[0086] Compared to the case where only the ground plate (320) is present, when the electrode (221) of the external carrier (220) is additionally formed, the electrostatic capacitance measured at the electrode (311) of the substrate (310) can increase. In this case, even when the electrostatic capacitance decreases due to movement of the internal carrier (210), the external carrier (220), and the ground plate (320), the measurement of the electrostatic capacitance can be facilitated.

[0087] The electrode (221) may include a plurality of electrodes. The electrode (221) may include four electrodes. The electrode (221) may include first to fourth electrodes. The electrode (221) may include first to fourth electrodes corresponding to the first to fourth electrodes (311-1, 311-2, 311-3, 311-4).

[0088] The outer carrier (220) may include a first groove (222). The first groove (222) may be an inner ball rail. A first ball (510) may be placed in the first groove (222). The first ball (510) may move along the first groove (222). Alternatively, the first ball (510) may rotate while at least a portion of the first ball (510) is accommodated in the first groove (222).

[0089] The outer carrier (220) may include a second groove (223). The second groove (223) may be an external ball rail. A second ball (520) may be placed in the second groove (223). The second ball (520) may move along the second groove (223). The second groove (223) may extend in the z-axis direction.

[0090] The outer carrier (220) may include a groove (224). The groove (224) may be formed on the inner surface of the outer carrier (220). The groove (224) may be formed concavely on the inner surface of the outer carrier (220). The protrusion (213) of the inner carrier (210) may be arranged in the groove (224) of the outer carrier (220).

[0091] The groove (224) can limit the movement of the inner carrier (210) within a preset range. When the inner carrier (210) rotates about the z-axis by a preset angle or more with respect to the outer carrier (220), the protrusion (213) of the inner carrier (210) can come into contact with the groove (224) of the outer carrier (220).

[0092] The outer carrier (220) may include a protrusion (225). The protrusion (225) may be a stopper. The protrusion (225) may be formed on an outer surface of the outer carrier (220). The protrusion (225) may protrude outward from the outer carrier (220). The protrusion (225) may be placed in a groove (112) of the fixing member (100).

[0093] The outer carrier (220) may include a protrusion (226). The protrusion (226) may be formed on the lower surface of the outer carrier (220). The protrusion (226) may protrude downward from the outer carrier (220). The protrusion (226) may protrude from the lower surface of the outer carrier (220).

[0094] The force-torque sensor may include a lead (230). The moving part (200) may include the lead (230). The lead (230) may be connected to the internal carrier (210). At least a portion of the lead (230) may be disposed on the base (110). At least a portion of the lead (230) may be disposed on the upper cover (120). At least a portion of the lead (230) may be disposed on the fixed part (100). At least a portion of the lead (230) may protrude beyond the fixed part (100). An external force may be applied to at least a portion of the lead (230) that protrudes beyond the fixed part (100). The external force may be applied to the lead (230). The lead (230) may be moved by the external force. The lead (230) may be coupled to the internal carrier (210). The lead (230) may be disposed on the internal carrier (210). The lead (230) may be placed on the inner carrier (210). The lead (230) may move integrally with the inner carrier (210). The lead (230) may be fixed to the inner carrier (210). At least a portion of the lead (230) may be exposed outside the fixing member (100). The lead (230) may be exposed to the outside and may move by an external force.

[0095] When a force is applied to the lead (230) in the direction of the first axis, the direction of the second axis, the direction of rotation about the first axis, the direction of rotation about the second axis, and the direction of rotation about the third axis, the internal carrier (210) can move with respect to the external carrier (220). When a force is applied to the lead (230) in the direction of the third axis, the internal carrier (210) and the external carrier (220) can move together with respect to the fixed part (100). At this time, the first axis may be the x-axis, the second axis may be the y-axis, and the third axis may be the z-axis.

[0096] The force-torque sensor may include a detection unit (300). The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100). The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100) in the x-axis direction. The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100) in the y-axis direction. The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100) in the yaw direction. The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100) in the pitch direction. The detection unit (300) may detect movement of the moving unit (200) with respect to the fixed unit (100) in the roll direction. The detection unit (300) can detect the z-axis movement of the moving unit (200) with respect to the fixed unit (100).

[0097] The detection unit (300) may include detection cells. The detection unit (300) may include a plurality of detection cells. The detection unit (300) may include four detection cells. The detection unit (300) may include first to fourth detection cells (300-1, 300-2, 300-3, 300-4).

[0098] Each of the first to fourth sensing cells (300-1, 300-2, 300-3, 300-4) can separately sense electrostatic capacitance. Through this, the movement of the moving part (200) in the yaw direction, pitch direction, roll direction, and z-axis direction can be separately detected.

[0099] The first sensing cell (300-1) may include a first electrode (311-1) and a first ground plate (320-1). The second sensing cell (300-2) may include a second electrode (311-2) and a second ground plate (320-2). The third sensing cell (300-3) may include a third electrode (311-3) and a third ground plate (320-3). The fourth sensing cell (300-4) may include a fourth electrode (311-4) and a fourth ground plate (320-4).

[0100] The force-torque sensor may include a substrate (310). The sensing unit (300) may include the substrate (310). The substrate (310) may be placed on the fixing unit (100). The substrate (310) may be placed on the lower cover (130). The substrate (310) may be placed on the base (110).

[0101] The substrate (310) may include an electrode (311). The electrode (311) may be formed on the surface of the substrate (310). The electrode (311) may be a positive electrode. The electrode (311) may be formed of metal.

[0102] The electrode (311) may include a first portion (311a). The first portion (311a) may be disposed on the upper surface of the substrate (310). The first portion (311a) may correspond to the wing portion (321) of the ground plate (320).

[0103] The electrode (311) may include a second portion (311b). The second portion (311b) may extend from the first portion (311a). The second portion (311b) may be disposed on the inner surface of the groove (312) of the substrate (310). The second portion (311b) may correspond to the protrusion (322) of the ground plate (320). The second portion (311b) may be in a bent form from the first portion (311a). The second portion (311b) may be disposed on the side surface of the substrate (310).

[0104] The second part (311b) may be connected to the first part (311a). Alternatively, the second part (311b) and the first part (311a) may be spaced apart from each other. This allows the capacitance in the first part (311a) and the capacitance in the second part (311b) to be measured separately.

[0105] The electrode (311) may include a plurality of electrodes. The electrode (311) may include four electrodes. The electrode (311) may include first to fourth electrodes (311-1, 311-2, 311-3, 311-4). The first to fourth electrodes (311-1, 311-2, 311-3, 311-4) may correspond to the first to fourth ground plates (320-1, 320-2, 320-3, 320-4).

[0106] The substrate (310) may include a groove (312). A protrusion (322) of a ground plate (320) may be positioned in the groove (312). The groove (312) may be formed by the outer surface of the circular substrate (310) being sunken inward. The groove (312) may be formed with a width greater than the thickness of the protrusion (322). The protrusion (322) may move within the groove (312).

[0107] Home (312) may include a plurality of home grooves. Home (312) may include four home grooves. Home (312) may include first to fourth home grooves.

[0108] The substrate (310) may include a ground terminal. A ground plate (320) may be coupled to the ground terminal. Through this, noise in the electrostatic capacity detected by the detection unit (300) may be eliminated.

[0109] The substrate (310) may include an upper surface facing the moving part (200). A first region (313) and a second region (314) in which no electrode (311) is disposed may be formed on the upper surface of the substrate (310).

[0110] The first region (313) may be formed in the central region of the upper surface of the substrate (310), which is circular when viewed from above. An electrode (311) may not be formed in the first region (313). A ground terminal may be formed in the first region (313). A second connecting portion (324) of the ground plate (320) may be connected to the first region (313).

[0111] The second region (314) may extend radially from the first region (313). An electrode (311) may not be formed in the second region (314). A conductive line of the substrate (310) may be arranged in the second region (314). For example, a conductive line for connecting a ground terminal to the outside may be arranged in the second region (314).

[0112] The second region (314) may include multiple second regions. The second region (314) may include four second regions. The second regions (314) may be arranged symmetrically with respect to the first region (313). The second region (314) may be arranged rotationally symmetrically with respect to the first region (313).

[0113] The force-torque sensor may include a ground plate (320). The sensing unit (300) may include the ground plate (320). At least a portion of the ground plate (320) may move integrally with the moving unit (200). At least a portion of the ground plate (320) may move integrally with the internal carrier (210). The ground plate (320) may be formed as a separate member and bonded to the internal carrier (210) with an adhesive. The ground plate (320) may be disposed on the internal carrier (210). The ground plate (320) may be coupled to the internal carrier (210). The ground plate (320) may be fixed to the internal carrier (210).

[0114] The ground plate (320) may include a plurality of ground plates. The ground plate (320) may include four ground plates. The ground plate (320) may include first to fourth ground plates (320-1, 320-2, 320-3, 320-4). The ground plate (320) may include first to fourth ground plates (320-1, 320-2, 320-3, 320-4) corresponding to the first to fourth electrodes (311-1, 311-2, 311-3, 311-4).

[0115] One or more of the ground plates among the plurality of ground plates may have a different shape from the other ground plates. In the present embodiment, the first ground plate (320-1) may have a different shape from each of the second to fourth ground plates (320-2, 320-3, 320-4). In this case, the second to fourth ground plates (320-2, 320-3, 320-4) may have the same shape.

[0116] The first ground plate (320-1) may have a different resistance value from each of the second to fourth ground plates (320-2, 320-3, 320-4) due to the tail portion (326). The tail portion (326) may include a shape with a high resistance. The tail portion (326) may be formed with a small cross-sectional area.

[0117] The ground plate (320) may include a wing portion (321). The wing portion (321) may face the electrode (311). The wing portion (321) may face the first part (311a) of the electrode (311). The wing portion (321) may be spaced apart from the first part (311a) of the electrode (311). The wing portion (321) may be positioned at a position corresponding to the first part (311a) of the electrode (311). The wing portion (321) may overlap with the electrode (311) in the z-axis direction. The wing portion (321) may overlap with the first part (311a) of the electrode (311) in the z-axis direction. The wing portion (321) may face the first part (311a) of the electrode (311) with an air gap therebetween. As a variation, an elastic dielectric may be placed between the wing portion (321) and the first portion (311a) of the electrode (311).

[0118] The ground plate (320) may include a protrusion (322). At least a portion of the protrusion (322) may be disposed in a groove (312) of the substrate (310). At least a portion of the protrusion (322) may be inserted into the groove (312) of the substrate (310). The protrusion (322) may be bent from the wing (321). The protrusion (322) may be bent and extended from the wing (321). The protrusion (322) may extend downward from the wing (321). At least a portion of the protrusion (322) may overlap the substrate (310) in a direction perpendicular to the z-axis.

[0119] The protrusion (322) may face the second part (311b) of the electrode (311). The protrusion (322) may be spaced apart from the second part (311b) of the electrode (311). The protrusion (322) may be arranged at a position corresponding to the second part (311b) of the electrode (311). The protrusion (322) may overlap the second part (311b) of the electrode (311) in a direction perpendicular to the z-axis. The protrusion (322) may face the second part (311b) of the electrode (311) with an air gap therebetween. As a variation, a dielectric having elasticity may be arranged between the protrusion (322) and the second part (311b) of the electrode (311).

[0120] The ground plate (320) may include a first coupling portion (323). The first coupling portion (323) may be coupled to the inner carrier (210).

[0121] The ground plate (320) may include a second coupling portion (324). The second coupling portion (324) may be coupled to the substrate (310). The second coupling portion (324) may be coupled to a ground terminal of the substrate (310).

[0122] The ground plate (320) may include a connecting portion (325). The connecting portion (325) may connect the first connecting portion (323) and the second connecting portion (324). The connecting portion (325) may be bent. The connecting portion (325) may include a shape that is bent multiple times. The connecting portion (325) may include a bent portion. The connecting portion (325) may include a plurality of strands. The connecting portion (325) may be deformable. Through this, the second connecting portion (324) is fixed to the substrate (310) and the first connecting portion (323) can move together with the internal carrier (210). That is, the connecting portion (325) may connect the first connecting portion (323) and the second connecting portion (324) such that the first connecting portion (323) is movable relative to the second connecting portion (324).

[0123] The ground plate (320) may include a hole (325a). The connecting portion (325) may include a hole (325a). The hole (325a) may be formed between the first connecting portion (323) and the second connecting portion (324). The hole (325a) may include a plurality of holes. The connecting portion (325) may be formed into a plurality of strands by the plurality of holes. The elasticity of the connecting portion (325) may be adjusted through the shape of the hole (325a).

[0124] The sensing unit (300) can sense temperature. The ground plate (320) can sense temperature. The ground plate (320) can sense the temperature of the ground plate (320). The ground plate (320) can include a shape for sensing the temperature of the ground plate (320). The ground plate (320) can include a structure for sensing the temperature of the ground plate (320).

[0125] The ground plate (320) may include a tail portion (326). The tail portion (326) may be a resistor. The tail portion (326) may have a structure for temperature sensing. The tail portion (326) may include a shape for temperature sensing. The tail portion (326) may extend to a width smaller than the wing portion (321). The tail portion (326) may be formed as a single strand having a shape that is bent multiple times. The tail portion (326) may have a meandering shape. The tail portion (326) may have a protruding shape. The tail portion (326) may have a zigzag shape. The tail portion (326) may include a rounded, folded shape.

[0126] The tail portion (326) and the protrusion portion (322) may be formed on different sides of the wing portion (321). The wing portion (321) may include a curved surface, a first side surface that is a plane connected to one end of the curved surface, and a second side surface that is a plane connected to the other end of the curved surface. The protrusion portion (322) may be formed on the first side of the wing portion (321), and the tail portion (326) may be formed on the second side of the wing portion (321).

[0127] One end of the tail portion (326) may be connected to the wing portion (321). At this time, the other end of the tail portion (326) may be formed as a free end. That is, the other end of the tail portion (326) may not be connected to the wing portion (321) but may be spaced apart.

[0128] As a variation, both ends of the tail portion (326) can be connected to the wing portion (321).

[0129] A part of the tail portion (326) of the ground plate (320) may overlap with the electrode (311) of the substrate (310) in the z-axis direction. At this time, another part of the tail portion (326) of the ground plate (320) may not overlap with the electrode (311) of the substrate (310) in the z-axis direction.

[0130] The force-torque sensor may include a coating layer. The ground plate (320) may include a coating layer. The ground plate (320) may include a coating layer for reinforcing the strength of the tail portion (326) formed of thin strands. The coating layer may be disposed on the tail portion (326). The coating layer may be formed on the tail portion (326). The coating layer may be disposed on the surface of the tail portion (326). The coating layer may be formed on the surface of the tail portion (326).

[0131] In the present embodiment, the temperature of the first sensing cell (300-1) can be detected through the first sensing cell (300-1) having the tail portion (326). In the present embodiment, the temperature change can be detected by comparing the sensing value of the first sensing cell (300-1) having the tail portion (326) with the sensing values ​​of the second to fourth sensing cells (300-2, 300-3, 300-4) not having the tail portion (326). Furthermore, the temperature can be recognized in real time. Through this, temperature compensation can be performed for the measured external force. As the temperature compensation is performed, the sensing performance of the force-torque sensor can be maintained precisely even in low or high temperature situations.

[0132] In this embodiment, for example, when the temperature changes, the amount of change in electrostatic capacity measured in the first sensing cell (300-1) may be different from the amount of change in electrostatic capacity measured in the second to fourth sensing cells (300-2, 300-3, 300-4). Therefore, the temperature can be recognized by comparing the difference in these amounts of change.

[0133] The width of the tail portion (326) of the ground plate (320) in the first direction perpendicular to the z-axis (see W2 in FIG. 12) may be smaller than the width of the wing portion (321) in the corresponding direction (see W1 in FIG. 12). The width of the tail portion (326) of the ground plate (320) in the first direction perpendicular to the z-axis (see W2 in FIG. 12) may be 37 to 50% of the width of the wing portion (321) in the corresponding direction (see W1 in FIG. 12). The width of the tail portion (326) of the ground plate (320) in the first direction perpendicular to the z-axis (see W2 in FIG. 12) may be 38 to 50% of the width of the wing portion (321) in the corresponding direction (see W1 in FIG. 12). The width of the tail portion (326) of the ground plate (320) in the first direction perpendicular to the z-axis (see W2 in FIG. 12) may be 34 to 54% of the width of the wing portion (321) in the corresponding direction (see W1 in FIG. 12).

[0134] The force-torque sensor may include an elastic member (400). The elastic member (400) may be coupled to an inner carrier (210) and an outer carrier (220). The elastic member (400) may be coupled to an upper portion of the inner carrier (210). The elastic member (400) may be coupled to an upper surface of the inner carrier (210). The elastic member (400) may be coupled to an upper portion of the outer carrier (220). The elastic member (400) may be coupled to an upper surface of the outer carrier (220).

[0135] The elastic member (400) can press the inner carrier (210) toward the outer carrier (220) so that the first ball (510) is in close contact with the inner carrier (210) and the outer carrier (220). When the elastic member (400) is assembled, the elasticity of the elastic member (400) can be used to press the inner carrier (210) toward the outer carrier (220). At this time, the inner carrier (210) can press the first ball (510) so that the first ball (510) is in close contact with the inner carrier (210) and the outer carrier (220).

[0136] The elastic member (400) may be a spring. The elastic member (400) may be formed of metal. The elastic member (400) may have elasticity.

[0137] The elastic member (400) may include an inner portion (410). The inner portion (410) may be coupled with an inner carrier (210). The inner portion (410) may be disposed on the inner carrier (210). The inner portion (410) may be fixed to the inner carrier (210). The inner portion (410) may be coupled to an upper surface of the inner carrier (210). The inner portion (410) may be disposed on an upper surface of the inner carrier (210). The inner portion (410) may be fixed to an upper surface of the inner carrier (210).

[0138] The elastic member (400) may include an outer portion (420). The outer portion (420) may be coupled to an outer carrier (220). The outer portion (420) may be disposed on the outer carrier (220). The outer portion (420) may be fixed to the outer carrier (220). The outer portion (420) may be coupled to an upper surface of the outer carrier (220). The outer portion (420) may be disposed on an upper surface of the outer carrier (220). The outer portion (420) may be fixed to an upper surface of the outer carrier (220).

[0139] The elastic member (400) may include a connecting portion (430). The connecting portion (430) may connect the inner portion (410) and the outer portion (420). The connecting portion (430) may elastically connect the inner portion (410) and the outer portion (420). The connecting portion (430) may have elasticity. The connecting portion (430) may have restoring force. The connecting portion (430) may include a bent shape. The connecting portion (430) may be formed by being bent multiple times. The connecting portion (430) may include a bent portion.

[0140] The force-torque sensor may include a guide member. The guide member may guide the movement of the moving part (200). The guide member may guide the movement of the moving part (200) relative to the fixed part (100). The guide member may guide the movement of the inner carrier (210) relative to the outer carrier (220).

[0141] The force-torque sensor may include a first ball (510). The guide member may include the first ball (510). The first ball (510) may be disposed between the inner carrier (210) and the outer carrier (220). The first ball (510) may guide movement of the inner carrier (210) with respect to the outer carrier (220). The inner carrier (210) may move in the yaw direction, the pitch direction, and the roll direction with respect to the outer carrier (220) by the first ball (510). However, when the inner carrier (210) is to move in the z-axis direction, the first ball (510) and the outer carrier (220) may move together with the inner carrier (210). The first ball (510) may include a plurality of balls.

[0142] The force-torque sensor may include a second ball (520). The guide member may include the second ball (520). The second ball (520) may be disposed between the outer carrier (220) and the fixing member (100). The second ball (520) may be disposed between the outer carrier (220) and the base (110). The second ball (520) may guide movement of the outer carrier (220) with respect to the base (110). The outer carrier (220) may move in the z-axis direction with respect to the base (110) by the second ball (520). At this time, the outer carrier (220) may move together with the inner carrier (210) and the lead (230).

[0143] The second ball (520) may include multiple balls. The second ball (520) may include at least two balls that overlap in the z-axis direction. Even when the external carrier (220) moves by at least two balls that overlap in the z-axis direction, tilt can be prevented.

[0144] The force-torque sensor may include a coupling member. The coupling member may couple two or more different members together. For example, the coupling member may be a screw. The coupling member may be a bolt.

[0145] The force-torque sensor may include an upper coupling member (610). The upper coupling member (610) may be coupled to a lead (230) and an inner carrier (210). The upper coupling member (610) may secure the lead (230) to the inner carrier (210).

[0146] The force-torque sensor may include a lower coupling member (620). The lower coupling member (620) may be coupled to the lower cover (130) and the base (110). The lower coupling member (620) may secure the lower cover (130) to the base (110).

[0147] The force-torque sensor may include an outer coupling member (630). The outer coupling member (630) may be coupled to the upper cover (120) and the base (110). The outer coupling member (630) may secure the upper cover (120) to the base (110).

[0148]

[0149] Below, the operation of the force-torque sensor according to the present embodiment is described with reference to the drawings.

[0150] Fig. 20 is a diagram for explaining a case where an external force having a component in the yaw direction or pitch direction is applied to a force-torque sensor according to the present embodiment. Fig. 21 is a diagram for explaining a change when an external force having a component in the roll direction is applied to a force-torque sensor according to the present embodiment. Fig. 22 is a diagram for explaining a case where an external force having a component in the z-axis direction is applied to a force-torque sensor according to the present embodiment.

[0151] When an external force having a component in at least one of the y-axis direction and the yaw direction is applied to the lead (230) of the force-torque sensor according to the present embodiment, the lead (230) can rotate or tilt around the x-axis (see yaw in FIG. 20). At this time, at least a part of the internal carrier (210) and the ground plate (320) can move integrally with the lead (230) (see A, B in FIG. 20). Meanwhile, since the fixed part (100) is maintained in a fixed state, the distance between the electrode (311) of the substrate (310) placed on the fixed part (100) and the ground plate (320) can be changed. For example, the electrostatic capacitance measured in the first sensing cell (300-1) and the second sensing cell (300-2) can decrease, and the electrostatic capacitance measured in the third sensing cell (300-3) and the fourth sensing cell (300-4) can increase. Through this, the force in the y-axis direction and the force in the y-direction direction of the external force applied to the lead (230) can be measured.

[0152] When an external force having a component in at least one direction of the x-axis direction and the pitch direction is applied to the lead (230) of the force-torque sensor according to the present embodiment, the lead (230) can be rotated or tilted around the y-axis. At this time, at least a part of the internal carrier (210) and the ground plate (320) can move integrally with the lead (230) (see A and B of FIG. 20). Meanwhile, since the fixed part (100) is maintained in a fixed state, the distance between the electrode (311) of the substrate (310) placed on the fixed part (100) and the ground plate (320) can be changed. For example, the electrostatic capacitance measured in the second sensing cell (300-2) and the third sensing cell (300-3) can decrease, and the electrostatic capacitance measured in the first sensing cell (300-1) and the fourth sensing cell (300-4) can increase. Through this, the force in the x-axis direction and the force in the pitch direction of the external force applied to the lead (230) can be measured.

[0153] When an external force having a roll direction component is applied to the lead (230) of the force-torque sensor according to the present embodiment, the lead (230) can rotate or tilt around the z-axis (see roll in FIG. 21). At this time, at least a part of the internal carrier (210) and the ground plate (320) can move integrally with the lead (230) (see a, b in FIG. 21). Meanwhile, since the fixed part (100) is maintained in a fixed state, the distance between the electrode (311) of the substrate (310) placed on the fixed part (100) and the ground plate (320) can be changed. In particular, the distance between the protrusion (322) of the ground plate (320) and the second part (311b) of the electrode (311) of the substrate (310) can be changed. Accordingly, the electrostatic capacitance measured in the first to fourth sensing cells (300-1, 300-2, 300-3, 300-4) may all increase or all decrease. However, the change in the electrostatic capacitance in the first part (311a) of the electrode (311) may be absent or minimal, and the change in the electrostatic capacitance in the second part (311b) of the electrode (311) may be large. Through this, the force in the roll direction component of the external force applied to the lead (230) may be measured.

[0154] When an external force having a z-axis component is applied to the lead (230) of the force-torque sensor according to the present embodiment, the lead (230) can move along the z-axis (see B of FIG. 22). At this time, at least a portion of the outer carrier (220), the inner carrier (210), and the ground plate (320) can move integrally with the lead (230) (see A and B of FIG. 22). Meanwhile, since the fixed part (100) is maintained in a fixed state, the distance between the electrode (311) of the substrate (310) placed on the fixed part (100) and the ground plate (320) can be changed. In particular, the distance between the wing part (321) of the ground plate (320) and the first part (311a) of the electrode (311) of the substrate (310) can be changed. Accordingly, the electrostatic capacitance measured in the first to fourth sensing cells (300-1, 300-2, 300-3, 300-4) may all increase or all decrease. However, the change in the electrostatic capacitance in the first part (311a) of the electrode (311) may be large, and the change in the electrostatic capacitance in the second part (311b) of the electrode (311) may be absent or minimal. Furthermore, since the distance between the electrode (221) of the external carrier (220) and the first part (311a) of the electrode (311) of the substrate (310) also changes, the change in the electrostatic capacitance in the first part (311a) of the electrode (311) may become larger. Through this, the force of the z-axis direction component of the external force applied to the lead (230) can be measured.

[0155]

[0156] Below, the configuration of the robot according to this embodiment is described.

[0157] A robot may include a body. The robot may include an arm connected to the body. The arm of the robot may include a gripping portion. The gripping portion may include, for example, a finger shape. The force-torque sensor of the present embodiment may be disposed on the gripping portion of the arm. The arm of the robot may include a joint. The force-torque sensor of the present embodiment may be disposed on a joint of the arm.

[0158]

[0159] Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. Fixed government; A moving part arranged on the above fixed part; a substrate disposed on the above-mentioned fixed portion and including an electrode; and At least a portion of the ground plate comprises a ground plate that moves integrally with the moving part, The ground plate is a force-torque sensor including a shape for detecting the temperature of the ground plate.

2. In paragraph 1, A force-torque sensor, wherein the ground plate includes a wing portion facing the electrode of the substrate and a tail portion extending from the wing portion with a width smaller than the wing portion.

3. In paragraph 2, A force-torque sensor in which the above tail portion is formed as a single strand having a shape that is folded multiple times.

4. In paragraph 2, One end of the above tail portion is connected to the above wing portion, A force-torque sensor in which the other end of the above tail portion is formed as a free end.

5. In paragraph 2, A force-torque sensor in which both one end of the above tail portion and the other end of the above tail portion are connected to the above wing portion.

6. In paragraph 2, The wing portion of the ground plate overlaps the electrode of the substrate in the z-axis direction, A part of the tail portion of the ground plate overlaps the electrode of the substrate in the z-axis direction, A force-torque sensor in which another part of the tail portion of the ground plate does not overlap with the electrode of the substrate in the z-axis direction.

7. In paragraph 2, The electrode of the substrate includes a first part disposed on the upper surface of the substrate and a second part disposed on the side of the substrate, The wing portion of the above ground plate faces the first portion of the above electrode, A force-torque sensor wherein the ground plate extends from the wing portion and includes a protrusion facing the second portion of the electrode.

8. In paragraph 7, A force-torque sensor in which the tail portion and the protrusion portion are formed on different sides of the wing portion.

9. In paragraph 7, The above substrate includes a ground terminal, The ground plate includes a first coupling portion coupled to the moving portion, a second coupling portion coupled to the ground terminal of the substrate, and a connecting portion connecting the first coupling portion and the second coupling portion. A force-torque sensor wherein the connecting portion includes a plurality of holes formed between the first connecting portion and the second connecting portion.

10. In paragraph 2, A force-torque sensor comprising a coating layer disposed on the surface of the above tail portion.

Images