Force-torque sensor and robot

Abstract

The present embodiment relates to a force-torque sensor comprising: a fixed portion; a moving portion disposed on the fixed portion; a substrate disposed on the fixed portion and including an electrode; a ground plate at least a portion of which moves integrally with the moving portion; and a first liquid and a second liquid disposed between the fixed portion and the moving portion, wherein the second liquid has a greater specific gravity than the first liquid.

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 in which the influence of gravity on the strength and direction of the detected external force is minimized.

[0010] A force-torque sensor according to a first embodiment of the present invention comprises: a fixed part; a moving part disposed on the fixed part; a substrate disposed on the fixed part and including an electrode; a ground plate at least a portion of which moves integrally with the moving part; and a first liquid and a second liquid disposed between the fixed part and the moving part, wherein the second liquid may have a greater specific gravity than the first liquid.

[0011] The second liquid may have a dielectric constant lower than that of the first liquid.

[0012] The space between the fixed part and the movable part is sealed, and the space between the fixed part and the movable part can be filled with the first liquid and the second liquid.

[0013] In an up position where the substrate is placed below the ground plate, the second liquid can be placed between the substrate and the ground plate.

[0014] In a down position where the substrate is placed on top of the ground plate, the first liquid can be placed between the substrate and the ground plate.

[0015] In a side position where the substrate and the ground plate are arranged at the same height, the first liquid may be arranged in some area between the substrate and the ground plate, and the second liquid may be arranged in the remaining area.

[0016] The first liquid may be water, and the second liquid may be glycerin.

[0017] The first liquid may be water, and the second liquid may be acetic acid.

[0018] The first liquid may be oil, and the second liquid may be crude oil.

[0019] The moving part may include an inner carrier and a lead coupled to the inner carrier and at least a portion of which is exposed to the outside, the fixed part may include a base and a sealing cover coupled to the base, and the sealing cover may include an outer portion coupled to the base, an inner portion in contact with the lead, a connecting portion connecting the outer portion and the inner portion, and a spring that urges the inner portion toward the lead.

[0020] The above fixed part includes a lower cover coupled to the base and positioned on the opposite side of the sealing cover, and a sealing plate may be positioned between the base and the lower cover.

[0021] The electrode of the above substrate may include four electrodes, and the ground plate may include four ground plates corresponding to the four electrodes.

[0022] 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.

[0023] 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.

[0024] A robot according to the first embodiment of the present invention may include the force-torque sensor.

[0025] A force-torque sensor according to a second embodiment of the present invention may include a fixed portion; an inner carrier disposed within the fixed portion; an outer carrier disposed between the fixed portion and the inner carrier; a first ball disposed between the inner carrier and the outer carrier; a second ball disposed between the fixed portion and the outer carrier; a substrate disposed on the fixed portion and including an electrode; and a ground plate at least a portion of which moves integrally with the inner carrier.

[0026] The above external carrier can move in the z-axis direction with respect to the above fixed part.

[0027] The outer carrier can move together with the inner carrier when the inner carrier moves in the z-axis direction.

[0028] The inner carrier can move 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.

[0029] The inner carrier may include an electrode disposed on a surface of the inner carrier and connected to the ground plate.

[0030] The above outer carrier may include electrodes arranged on the lower surface and inner surface of the above outer carrier.

[0031] The substrate may include a groove, and the ground plate may include a protrusion at least partially disposed in the groove.

[0032] The electrode includes a first portion disposed on an upper surface of the substrate, and a second portion extending from the first portion and disposed on an inner surface of the groove of the substrate, the ground plate includes a wing portion facing the first portion of the electrode, and the protrusion of the ground plate can be bent from the wing portion and face the second portion of the electrode.

[0033] At least a portion of the protrusion of the ground plate may overlap the substrate in a direction perpendicular to the z-axis.

[0034] The substrate includes a ground terminal, and the ground plate can be coupled to the ground terminal of the substrate.

[0035] The ground plate may include a first coupling portion coupled to the internal carrier, 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.

[0036] The electrodes may include first to fourth electrodes, and the ground plate may include first to fourth ground plates corresponding to the first to fourth electrodes.

[0037] The force-torque sensor includes a lead coupled to the inner carrier, and the lead is exposed to the outside and can be moved by an external force.

[0038] The force-torque sensor may include an elastic member coupled to the inner carrier and the outer carrier.

[0039] A robot according to a second embodiment of the present invention may include the force-torque sensor.

[0040] 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.

[0041] Furthermore, the size of the force-torque sensor can be miniaturized through the capacitor type sensing unit.

[0042] In addition, since the first embodiment of the present invention obtains a detection value with minimized influence of gravity, precise detection capability can be maintained regardless of the posture of the force-torque sensor.

[0043] FIG. 1 is a perspective view of a force-torque sensor according to a first embodiment of the present invention.

[0044] Figure 2 is a cross-sectional view taken along line AA of Figure 1.

[0045] FIG. 3 is a cross-sectional view of a force-torque sensor according to a first embodiment of the present invention, cut perpendicular to the z-axis and viewed from above.

[0046] Figure 4 is an exploded perspective view of a force-torque sensor according to a first embodiment of the present invention.

[0047] FIG. 5 is an exploded perspective view of a force-torque sensor according to the first embodiment of the present invention, viewed from a different direction from FIG. 4.

[0048] Figure 6 is a perspective view of Figure 1 with the lead omitted.

[0049] Figures 7 (a) to (d) are drawings showing a sealing cover of a force-torque sensor according to a first embodiment of the present invention.

[0050] Fig. 8 is a perspective view of Fig. 6 with the sealing cover and related components omitted.

[0051] Figure 9 is a perspective view of Figure 8 with the base omitted.

[0052] Fig. 10 is a perspective view of Fig. 9 with the external carrier and related components omitted.

[0053] Fig. 11 is a perspective view of Fig. 10 with the internal carrier and related components omitted.

[0054] Figure 12a is a perspective view and a partially enlarged view of a sensing portion of a force-torque sensor according to a first embodiment of the present invention.

[0055] FIG. 12b is a perspective view of a substrate of a force-torque sensor according to a first embodiment of the present invention.

[0056] Fig. 13 is a bottom perspective view of a force-torque sensor according to a first embodiment of the present invention.

[0057] Fig. 14 is a bottom perspective view of Fig. 13 with the lower cover and related components omitted.

[0058] Fig. 15 is a bottom perspective view of Fig. 14 with the substrate omitted.

[0059] Figure 16 is a bottom perspective view of Figure 15 with the ground plate and base omitted.

[0060] Fig. 17 is a bottom perspective view of Fig. 16 with the external carrier and related components omitted.

[0061] Figure 18 (a) is a conceptual diagram showing a state in which a force-torque sensor according to the first embodiment of the present invention is arranged in an up position, and Figure 18 (b) is a conceptual diagram showing a state in which a force-torque sensor according to the first embodiment of the present invention is arranged in a down position.

[0062] Figures 19 (a) and (b) are conceptual diagrams showing a state in which a force-torque sensor according to the first embodiment of the present invention is placed in a side position.

[0063] 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 first embodiment of the present invention.

[0064] 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 first embodiment of the present invention.

[0065] 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 first embodiment of the present invention.

[0066] Fig. 23 is a perspective view of a force-torque sensor according to a second embodiment of the present invention.

[0067] Fig. 24 is a cross-sectional view taken along line AA of Fig. 23.

[0068] FIG. 25 is a cross-sectional view of a force-torque sensor according to a second embodiment of the present invention, cut perpendicular to the z-axis and viewed from above.

[0069] Fig. 26 is an exploded perspective view of a force-torque sensor according to a second embodiment of the present invention.

[0070] FIG. 27 is an exploded perspective view of a force-torque sensor according to a second embodiment of the present invention, viewed from a different direction from FIG. 26.

[0071] Fig. 28 is a perspective view of Fig. 23 with the lead and related components omitted.

[0072] Figure 29 is a perspective view of Figure 28 with the upper cover and related components omitted.

[0073] Figure 30 is a perspective view of Figure 29 with the base and elastic member omitted.

[0074] Fig. 31 is a perspective view of Fig. 30 with the external carrier and related components omitted.

[0075] Figure 32 is a perspective view of Figure 31 with the internal carrier and related components omitted.

[0076] Figure 33a is a perspective view of a sensing unit of a force-torque sensor according to a second embodiment of the present invention.

[0077] FIG. 33b is a perspective view of a substrate of a force-torque sensor according to a second embodiment of the present invention.

[0078] Fig. 34 is a bottom perspective view of a force-torque sensor according to a second embodiment of the present invention.

[0079] Figure 35 is a bottom perspective view of Figure 34 with the lower cover and related components omitted.

[0080] Figure 36 is a bottom perspective view and a partially enlarged view of Figure 35 with the substrate omitted.

[0081] Figure 37 is a bottom perspective view of Figure 36 with the ground plate omitted.

[0082] Figure 38 is a bottom perspective view of Figure 37 with the base omitted.

[0083] Figure 39 is a bottom perspective view of Figure 38 with the external carrier and related components omitted.

[0084] FIG. 40 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 a second embodiment of the present invention.

[0085] Figure 41 is a drawing for explaining changes when an external force having a roll direction component is applied to a force-torque sensor according to a second embodiment of the present invention.

[0086] FIG. 42 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 a second embodiment of the present invention.

[0087] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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”.

[0096] Hereinafter, one of the “upper connecting member (610)” and the “outer connecting member (630)” may be referred to as the “first connecting member” and the other may be referred to as the “second connecting member”. In addition, each of the “upper connecting member (610)” and the “outer connecting member (630)” may be referred to as a “connecting member”.

[0097] Hereinafter, “the first ball (510)” and “the second ball (520)” may each be referred to as “balls.”

[0098] Hereinafter, one of the “internal carrier (1210)” and the “external carrier (1220)” may be referred to as the “first carrier” and the other may be referred to as the “second carrier”.

[0099] Hereinafter, one of the “upper coupling member (1610)”, the “lower coupling member (1620)”, and the “outer coupling member (1630)” 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 (1610)”, the “lower coupling member (1620)”, and the “outer coupling member (1630)” may be referred to as a “coupling member”.

[0100] Hereinafter, “the first ball (1510)” and “the second ball (1520)” may each be referred to as “balls.”

[0101] 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.”

[0102] 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.”

[0103]

[0104] Hereinafter, the configuration of a force-torque sensor according to a first embodiment of the present invention will be described with reference to the drawings.

[0105] FIG. 1 is a perspective view of a force-torque sensor according to a first embodiment of the present invention. 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 first embodiment of the present invention, cut perpendicular to the z-axis and viewed from above. FIG. 4 is an exploded perspective view of the force-torque sensor according to the first embodiment of the present invention. FIG. 5 is an exploded perspective view of the force-torque sensor according to the first embodiment of the present invention, viewed from a different direction from FIG. 4. FIG. 6 is a perspective view of FIG. 1 with the lid omitted. FIG. 7 (a) to (d) are drawings illustrating a sealing cover of the force-torque sensor according to the first embodiment of the present invention. FIG. 8 is a perspective view of FIG. 6 with the sealing cover and related components omitted. FIG. 9 is a perspective view of FIG. 8 with the base omitted. Fig. 10 is a perspective view of Fig. 9 with the external carrier and related components omitted. Fig. 11 is a perspective view of Fig. 10 with the internal carrier and related components omitted. Fig. 12a is a perspective view and a partially enlarged view of a sensing unit of a force-torque sensor according to a first embodiment of the present invention. Fig. 12b is a perspective view of a substrate of a force-torque sensor according to a first embodiment of the present invention. Fig. 13 is a bottom perspective view of a force-torque sensor according to a first embodiment of the present invention. Fig. 14 is a bottom perspective view of Fig. 13 with the lower cover and related components omitted. Fig. 15 is a bottom perspective view of Fig. 14 with the substrate omitted. Fig. 16 is a bottom perspective view of Fig. 15 with the ground plate and base omitted. Fig. 17 is a bottom perspective view of Fig. 16 with the external carrier and related components omitted. Fig. 18 (a) is a conceptual diagram illustrating a state in which a force-torque sensor according to a first embodiment of the present invention is arranged in an up position, and Fig. 18 (b) is a conceptual diagram illustrating a state in which a force-torque sensor according to a first embodiment of the present invention is arranged in a down position. Fig. 19 (a) and (b) are conceptual diagrams illustrating a state in which a force-torque sensor according to a first embodiment of the present invention is arranged in a side position.

[0106] 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.

[0107] 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.

[0108] 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 sealing cover (120). The base (110) may be disposed under the sealing cover (120). The base (110) may be disposed between the lower cover (130) and the sealing 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).

[0109] 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).

[0110] 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).

[0111] In the first embodiment of the present invention, 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).

[0112] The force-torque sensor may include a sealing cover (120). The fixing member (100) may include the sealing cover (120). The sealing cover (120) may be disposed on the base (110). The sealing cover (120) may be coupled to the base (110). The sealing cover (120) may be coupled to the upper surface of the base (110). The sealing cover (120) may be fixed to the base (110). The sealing cover (120) may be disposed between the base (110) and the lid (230).

[0113] The sealing cover (120) can seal the space between the moving part (200) and the sealing cover (120). The sealing cover (120) can be in contact with the moving part (200). The sealing cover (120) can be in contact with the lid (230). The sealing cover (120) can be formed of rubber. The sealing cover (120) can be a sealing member.

[0114] Liquid flowing in or out between the lid (230) and the sealing cover (120) can be blocked by the sealing cover (120). The sealing cover (120) is pressed toward the lid (230) by the spring (125), so that liquid flowing in or out between the lid (230) and the sealing cover (120) can be blocked.

[0115] Liquid flowing in or out between the sealing cover (120) and the base (110) can be blocked by the sealing cover (120). Since the sealing cover (120) is pressed toward the base (110) by the outer connecting member (630), liquid flowing in or out between the sealing cover (120) and the base (110) can be blocked.

[0116] The sealing cover (120) may include an inner portion (121). The inner portion (121) may be in contact with the moving portion (200). The inner portion (121) may be disposed on the moving portion (200). The inner portion (121) may be fixed to the moving portion (200). The inner portion (121) may be coupled to the moving portion (200). The inner portion (121) may be pressed toward the moving portion (200). The inner portion (121) may be in contact with the lead (230). The inner portion (121) may be disposed on the lead (230). The inner portion (121) may be fixed to the lead (230). The inner portion (121) may be coupled to the lead (230). The inner portion (121) may be pressed toward the lead (230).

[0117] The sealing cover (120) may include an outer portion (122). The outer portion (122) may be coupled to the base (110). The outer portion (122) may be placed on the base (110). The outer portion (122) may be fixed to the base (110). The outer portion (122) may be in contact with the base (110). The outer portion (122) may be pressed toward the base (110).

[0118] The sealing cover (120) may include a connecting portion (123). The connecting portion (123) may connect the outer portion (122) and the inner portion (121). The connecting portion (123) may be elastic. The connecting portion (123) may elastically connect the outer portion (122) and the inner portion (121). The connecting portion (123) may include a bent shape. The thickness of the connecting portion (123) may be smaller than the thickness of the outer portion (122).

[0119] The sealing cover (120) may include a plate (124). The plate (124) may be formed of metal. The plate (124) may be disposed within the outer portion (122) of the sealing cover (120). The plate (124) may be inserted into the outer portion (122) of the sealing cover (120) by an insert injection molding method. As a variation, the plate (124) may be attached to the lower surface of the sealing cover (120). The plate (124) may be disposed on the lower surface of the sealing cover (120). The plate (124) may be coupled to the lower surface of the sealing cover (120). The plate (124) may be fixed to the lower surface of the sealing cover (120) using a screw as a connecting member. The plate (124) may maintain the shape of the sealing cover (120). The plate (124) can reinforce the strength of the sealing cover (120). The sealing cover (120) can include a hole passing through the outer connecting member (630).

[0120] The sealing cover (120) may include a spring (125). The spring (125) may pressurize the inner side (121) of the sealing cover (120) toward the moving part (200). The spring (125) may pressurize the inner side (121) of the sealing cover (120) toward the lid (230). The spring (125) may be arranged in the lower groove (127) of the sealing cover (120). The spring (125) may have elasticity. The spring (125) may be an elastic member. The spring (125) may be a coil spring. The spring (125) may be formed in a circular shape. The spring (125) may have elasticity acting toward the center of the circle. The spring (125) may pressurize the inner side (121) of the sealing cover (120) toward the center. The spring (125) may have a force that compresses toward the center. The compressive force of the spring (125) allows the sealing cover (120) to come into contact with the lid (230). Through this, even if the sealing cover (120) is worn due to movement of the lid (230), the spring (125) can maintain contact force between the lid (230) and the sealing cover (120).

[0121] The inner part (121) of the sealing cover (120) can wrap the spring (125) from the upper, lower, and inner sides. At this time, the outer side of the spring (125) can be opened.

[0122] The sealing cover (120) may include an upper groove (126). The upper groove (126) may be formed between the outer portion (122) and the connecting portion (123) in a direction perpendicular to the z-axis. The upper groove (126) may be formed on the upper surface of the sealing cover (120). The upper groove (126) may form a separation space between the outer portion (122) and the connecting portion (123). Through this, when the lead (230) moves, the connecting portion (123) may move toward the outer portion (122).

[0123] The sealing cover (120) may include a lower groove (127). The lower groove (127) may be formed between the inner portion (121) and the connecting portion (123) in a direction perpendicular to the z-axis. The lower groove (127) may be formed on the lower surface of the sealing cover (120). The lower groove (127) may form a separation space between the inner portion (121) and the connecting portion (123). Through this, when the lead (230) moves, the inner portion (121) may move toward the connecting portion (123). The lower groove (127) may overlap with the upper groove (126) in a direction perpendicular to the z-axis.

[0124] The sealing cover (120) may include a hole (128). The outer portion (122) of the sealing cover (120) may include a hole (128). The hole (128) may be a screw hole. An outer coupling member (630) may be coupled to the hole (128). The outer coupling member (630) may be arranged in the hole (128). The outer coupling member (630) may pass through the hole (128). The outer coupling member (630) may pass through the sealing cover (120) through the hole (128).

[0125] 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 disposed opposite the lead (230). The lower cover (130) may be disposed 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 hole or groove through which the substrate (310) passes. The lower cover (130) may be disposed opposite the sealing cover (120).

[0126] The force-torque sensor may include a sealing plate (140). The sealing plate (140) may be placed between the base (110) and the lower cover (130). The sealing plate (140) may prevent the first liquid (410) and the second liquid (420) from leaking between the base (110) and the lower cover (130). The sealing plate (140) may seal or seal the space between the base (110) and the lower cover (130).

[0127] The force-torque sensor may include a sealing member (150). The lower cover (130) may include a substrate extraction hole through which a connecting substrate that is electrically connected to the substrate (310) is extracted to the outside of the force-torque sensor. The connecting substrate may be placed in the substrate extraction hole of the lower cover (130). The sealing member (150) may prevent the first liquid (410) and the second liquid (420) from leaking out through the substrate extraction hole of the lower cover (130). The sealing member (150) may seal or seal a space between the connecting substrate and the lower cover (130).

[0128] The force-torque sensor may include a sealing ring (160). The sealing ring (160) may be positioned between the upper coupling member (610) and the lid (230). The sealing ring (160) may seal between the upper coupling member (610) and the lid (230). The sealing ring (160) may prevent water from flowing between the upper coupling member (610) and the lid (230). The sealing ring (160) may be positioned to surround the outer circumferential surface of the upper coupling member (610).

[0129] 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).

[0130] 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.

[0131] 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.

[0132] The inner carrier (210) and the outer carrier (220) can move integrally in the z-axis direction with respect to the fixed part (100).

[0133] 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.

[0134] 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.

[0135] 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).

[0136] 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).

[0137] 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).

[0138] 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.

[0139] 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.

[0140] 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.

[0141] 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).

[0142] 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).

[0143] 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.

[0144] 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).

[0145] 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).

[0146] 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).

[0147] 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).

[0148] 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 sealing 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) protruding 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.

[0149] 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.

[0150] 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).

[0151] 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).

[0152] 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.

[0153] 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).

[0154] 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).

[0155] 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.

[0156] 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).

[0157] 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 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).

[0158] 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.

[0159] 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).

[0160] The substrate (310) may include a groove. A protrusion (322) of a ground plate (320) may be positioned in the groove. The groove may be formed by the outer surface of the circular substrate (310) being sunken inward. The groove may be formed with a width greater than the thickness of the protrusion (322). The protrusion (322) may move within the groove.

[0161] A home may include multiple homes. A home may include four homes. A home may include first to fourth homes.

[0162] 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.

[0163] 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).

[0164] 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).

[0165] 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).

[0166] 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 around the first region (313).

[0167] 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).

[0168] 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).

[0169] 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 first embodiment of the present invention, 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.

[0170] 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.

[0171] 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).

[0172] The ground plate (320) may include a protrusion (322). At least a portion of the protrusion (322) may be disposed in a groove of the substrate (310). At least a portion of the protrusion (322) may be inserted into the groove 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.

[0173] 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).

[0174] The ground plate (320) may include a first coupling portion (323). The first coupling portion (323) may be coupled to the inner carrier (210).

[0175] 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).

[0176] 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).

[0177] 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).

[0178] 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).

[0179] 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.

[0180] 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).

[0181] 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.

[0182] As a variation, both ends of the tail portion (326) can be connected to the wing portion (321).

[0183] 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.

[0184] In the first embodiment of the present invention, 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 first embodiment of the present invention, 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.

[0185] In the first embodiment of the present invention, 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). Accordingly, the temperature can be recognized by comparing the difference in these amounts of change.

[0186] The force-torque sensor may include a first liquid (410). The first liquid (410) may be disposed between the fixed part (100) and the moving part (200). The first liquid (410) may be disposed in the internal space of the force-torque sensor. The first liquid (410) may be disposed within the fixed part (100). The first liquid (410) may be disposed between the fixed part (100) and the external carrier (220). The first liquid (410) may be disposed between the external carrier (220) and the internal carrier (210).

[0187] The force-torque sensor may include a second liquid (420). The second liquid (420) may be disposed between the fixed part (100) and the moving part (200). The second liquid (420) may be disposed in the internal space of the force-torque sensor. The second liquid (420) may be disposed within the fixed part (100). The second liquid (420) may be disposed between the fixed part (100) and the external carrier (220). The second liquid (420) may be disposed between the external carrier (220) and the internal carrier (210).

[0188] The space between the fixed part (100) and the movable part (200) can be sealed. At this time, the space between the fixed part (100) and the movable part (200) can be filled with the first liquid (410) and the second liquid (420).

[0189] The specific gravity of the second liquid (420) and the specific gravity of the first liquid (410) may be different. The second liquid (420) may have a greater specific gravity than the first liquid (410). Accordingly, the second liquid (420) may be placed below the first liquid (410). The difference in specific gravity between the first liquid (410) and the second liquid (420) may be 5 to 50%. Additionally, the difference in specific gravity between the first liquid (410) and the second liquid (420) may be 7 to 13%. The first liquid (410) and the second liquid (420) may not be mixed with each other.

[0190] The second liquid (420) may have a lower dielectric constant than the first liquid (410). The difference in dielectric constant between the first liquid (410) and the second liquid (420) may be selected in proportion to the weight of the moving part (200). That is, when the weight of the moving part (200) is heavy, the difference in dielectric constant between the first liquid (410) and the second liquid (420) may be increased, and when the weight of the moving part (200) is light, the difference in dielectric constant between the first liquid (410) and the second liquid (420) may be decreased.

[0191] In one embodiment, the first liquid (410) may be water and the second liquid (420) may be glycerin. Water may have a specific gravity of 1 and a dielectric constant of 80.4. Glycerin may have a specific gravity of 1.26 and a dielectric constant of 42.5.

[0192] In another embodiment, the first liquid (410) may be water and the second liquid (420) may be acetic acid. Water may have a specific gravity of 1 and a dielectric constant of 80.4. Acetic acid may have a specific gravity of 1.1 and a dielectric constant of 6.2.

[0193] In another embodiment, the first liquid (410) may be oil and the second liquid (420) may be crude oil. The oil may have a specific gravity of 0.9 and a dielectric constant greater than approximately 2. The crude oil may have a specific gravity of 0.65 to 0.8 and a dielectric constant of approximately 2.

[0194] As shown in (a) of Fig. 18, in an up position where the substrate (310) is placed below the ground plate (320), a second liquid (420) may be placed between the substrate (310) and the ground plate (320). Therefore, the electrostatic capacitance measured by the detection unit (300) in the up position of the force-torque sensor is the dielectric constant (ε) of the second liquid (420). r2 ) can be proportional to. In the up posture, when an external force (F1) presses the moving part (200) downward, the force due to gravity (F2) can also press the moving part (200) downward.

[0195] As shown in (b) of Fig. 18, in a down position where the substrate (310) is placed on the ground plate (320), a first liquid (410) can be placed between the substrate (310) and the ground plate (320). Therefore, the electrostatic capacitance measured by the detection unit (300) in the down position of the force-torque sensor is the dielectric constant (ε) of the first liquid (410). r1) can be proportional to the force. In the down posture, when the external force (F1) presses the moving part (200) upward, the force due to gravity (F2) can press the moving part (200) downward in the opposite direction.

[0196] In the first embodiment of the present invention, the dielectric constant of the second liquid (420) that affects the electrostatic capacity measured by the sensing unit (300) in an up position in which the moving unit (200) and the ground plate (320) are pressed toward the substrate (310) by gravity may be smaller than the dielectric constant of the first liquid (410).

[0197] Additionally, the dielectric constant of the first liquid (410) that affects the electrostatic capacity measured by the sensing unit (300) in a down position where the moving unit (200) and the ground plate (320) are pressed away from the substrate (310) by gravity may be greater than the dielectric constant of the second liquid (420).

[0198] Therefore, a smaller dielectric constant can be applied in the up position than in the down position, thereby canceling out or compensating for changes in capacitance due to gravity. In addition, a larger dielectric constant can be applied in the down position than in the up position, thereby canceling out or compensating for changes in capacitance due to gravity. That is, in the first embodiment of the present invention, a detection value with minimized effects of gravity is obtained, so that precise detection capability can be maintained regardless of the posture of the force-torque sensor.

[0199] As shown in (a) and (b) of FIG. 19, in a side position where the substrate (310) and the ground plate (320) are arranged at the same height, the first liquid (410) may be arranged in some areas between the substrate (310) and the ground plate (320), and the second liquid (420) may be arranged in the remaining areas. Accordingly, the electrostatic capacitance measured by the detection unit (300) in the side position of the force-torque sensor is the dielectric constant (ε) of the first liquid (410). r1 ) and the dielectric constant (ε) of the second liquid (420) r2) can be influenced by everyone. In the side posture, when an external force (F1) presses the moving part (200) laterally, the force due to gravity (F2) can press the moving part (200) downward.

[0200] In the first embodiment of the present invention, both the first liquid (410) and the second liquid (420) may be insulating materials. However, as a variation, at least one of the first liquid (410) and the second liquid (420) may be a non-insulating material. In this case, an insulating coating layer may be disposed on the surface of the electrode (311) of the substrate (310). The insulating coating layer may include an oxide film. The insulating coating layer may be formed by parylene coating. Furthermore, an insulating coating layer may also be disposed on the surface of the ground plate (320).

[0201] 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).

[0202] 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.

[0203] 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).

[0204] 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.

[0205] 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.

[0206] 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).

[0207] Alternatively, the force-torque sensor may include a lower coupling member. The lower coupling member may be coupled to a lower cover (130) and a base (110). The lower coupling member may secure the lower cover (130) to the base (110). In the first embodiment of the present invention, the lower cover (130) may be bonded to the base (110) using an adhesive.

[0208] The force-torque sensor may include an outer coupling member (630). The outer coupling member (630) may be coupled to a sealing cover (120) and a base (110). The outer coupling member (630) may secure the sealing cover (120) to the base (110).

[0209]

[0210] Hereinafter, the operation of a force-torque sensor according to a first embodiment of the present invention will be described with reference to the drawings.

[0211] FIG. 20 is a diagram for explaining a case where an external force having a yaw or pitch direction component is applied to a force-torque sensor according to a first embodiment of the present invention. FIG. 21 is a diagram for explaining a change when an external force having a roll direction component is applied to a force-torque sensor according to a first embodiment of the present invention. FIG. 22 is a diagram for explaining a case where an external force having a z-axis direction component is applied to a force-torque sensor according to a first embodiment of the present invention.

[0212] 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 first embodiment of the present invention, 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) disposed 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.

[0213] 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 first embodiment of the present invention, the lead (230) can rotate or tilt 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) disposed 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.

[0214] When an external force having a roll direction component is applied to the lead (230) of the force-torque sensor according to the first embodiment of the present invention, 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.

[0215] When an external force having a z-axis component is applied to the lead (230) of the force-torque sensor according to the first embodiment of the present invention, 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) arranged 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 portion (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.

[0216]

[0217] Below, the configuration of a robot according to the first embodiment of the present invention is described.

[0218] A robot may include a body. The robot may include an arm member connected to the body. The arm member of the robot may include a gripping portion. The gripping portion may include, for example, a finger shape. The force-torque sensor of the first embodiment of the present invention may be disposed on the gripping portion of the arm member. The arm member of the robot may include a joint. The force-torque sensor of the first embodiment of the present invention may be disposed on a joint of the arm member.

[0219]

[0220] Below, the configuration of a force-torque sensor according to a second embodiment of the present invention is described with reference to the drawings.

[0221] Fig. 23 is a perspective view of a force-torque sensor according to a second embodiment of the present invention. Fig. 24 is a cross-sectional view taken along line AA of Fig. 23. Fig. 25 is a cross-sectional view taken along a line AA of Fig. 23, and viewed from above, of a force-torque sensor according to a second embodiment of the present invention. Fig. 26 is an exploded perspective view of a force-torque sensor according to a second embodiment of the present invention. Fig. 27 is an exploded perspective view of a force-torque sensor according to a second embodiment of the present invention viewed from a different direction from Fig. 26. Fig. 28 is a perspective view of Fig. 23 with the lead and related components omitted. Fig. 29 is a perspective view of Fig. 28 with the upper cover and related components omitted. Fig. 30 is a perspective view of Fig. 29 with the base and elastic member omitted. Fig. 31 is a perspective view of Fig. 30 with the external carrier and related components omitted. Fig. 32 is a perspective view of Fig. 31 with the internal carrier and related components omitted. Fig. 33a is a perspective view of a sensing unit of a force-torque sensor according to a second embodiment of the present invention. Fig. 33b is a perspective view of a substrate of a force-torque sensor according to a second embodiment of the present invention. Fig. 34 is a bottom perspective view of a force-torque sensor according to a second embodiment of the present invention. Fig. 35 is a bottom perspective view of Fig. 34 with the lower cover and related components omitted. Fig. 36 is a bottom perspective view and a partially enlarged view of Fig. 35 with the substrate omitted. Fig. 37 is a bottom perspective view of Fig. 36 with the ground plate omitted. Fig. 38 is a bottom perspective view of Fig. 37 with the base omitted. Fig. 39 is a bottom perspective view of Fig. 38 with the external carrier and related components omitted.

[0222] 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.

[0223] The force-torque sensor may include a fixed part (1100). The fixed part (1100) is a concept distinct from the moving part (1200) and may be a part that is relatively fixed when the moving part (1200) moves.

[0224] The force-torque sensor may include a base (1110). The fixing member (1100) may include the base (1110). The base (1110) may be disposed on the lower cover (1130). The base (1110) may be disposed on the lower cover (1130). The base (1110) may be disposed on the upper cover (1120). The base (1110) may be disposed under the upper cover (1120). The base (1110) may be disposed between the lower cover (1130) and the upper cover (1120). The base (1110) may accommodate an outer carrier (1220) therein. The base (1110) may accommodate an inner carrier (1210) therein. The base (1110) may be disposed on the outside of the outer carrier (1220). The base (1110) can be placed on the outside of the inner carrier (1210).

[0225] The base (1110) may include a groove (1111). The groove (1111) may be a ball rail. A second ball (1520) may be placed in the groove (1111). The groove (1111) may extend in the z-axis direction. The second ball (1520) may move along the groove (1111) of the base (1110). The second ball (1520) may roll along the groove (1111) of the base (1110).

[0226] The base (1110) may include a groove (1112). The groove (1112) may be formed on the inner surface of the fixing portion (1100). The groove (1112) may be formed on the inner surface of the base (1110). The groove (1112) may be formed concavely on the inner surface of the fixing portion (1100). The groove (1112) may be formed concavely on the inner surface of the base (1110). A protrusion (1225) of an external carrier (1220) may be arranged in the groove (1112) of the fixing portion (1100).

[0227] In the second embodiment of the present invention, the rotation of the external carrier (1220) with respect to the base (1110) can be prevented through the shape of the fit between the groove (1112) of the base (1110) and the protrusion (1225) of the external carrier (1220). When the external carrier (1220) rotates around the z-axis with respect to the fixed part (1100), the protrusion (1225) of the external carrier (1220) can come into contact with the groove (1112) of the fixed part (1100).

[0228] The force-torque sensor may include an upper cover (1120). The fixing member (1100) may include the upper cover (1120). The upper cover (1120) may be disposed on the base (1110). The upper cover (1120) may be disposed on the base (1110). The upper cover (1120) may be coupled to the base (1110). The upper cover (1120) may be coupled to an upper surface of the base (1110). The upper cover (1120) may be fixed to the base (1110). The upper cover (1120) may be disposed between the base (1110) and the lid (1230).

[0229] The force-torque sensor may include a lower cover (1130). The fixing member (1100) may include the lower cover (1130). The lower cover (1130) may form a bottom portion of the force-torque sensor. The lower cover (1130) may be positioned opposite the lead (1230). The lower cover (1130) may be positioned below the base (1110). The lower cover (1130) may be coupled to a lower surface of the base (1110). The lower cover (1130) may be coupled to the base (1110). The lower cover (1130) may include a groove through which the substrate (1140) passes.

[0230] The force-torque sensor may include a moving part (1200). The moving part (1200) may be disposed within the fixed part (1100). The moving part (1200) may be disposed on the fixed part (1100). The moving part (1200) may move relative to the fixed part (1100). When an external force is applied, the moving part (1200) may move relative to the fixed part (1100). At least a portion of the moving part (1200) may be disposed within the fixed part (1100). A portion of the moving part (1200) may be exposed outside the fixed part (1100). The moving part (1200) may be disposed on the lower cover (1130).

[0231] The force-torque sensor may include an inner carrier (1210). The moving part (1200) may include the inner carrier (1210). The inner carrier (1210) may be disposed within the fixed part (1100). The inner carrier (1210) may be disposed within the outer carrier (1220). The inner carrier (1210) may be disposed on the fixed part (1100). The inner carrier (1210) may be disposed within the base (1110). The inner carrier (1210) may include a curved surface. A first ball (1510) may be disposed on the curved surface of the inner carrier (1210). The inner carrier (1210) may be formed in a spherical shape at least partially. The inner carrier (1210) may be formed in a spherical shape at least partially so that the center of rotation does not change and remains constant. Through this, the internal carrier (1210) moves as intended by the designer, so the occurrence of crosstalk can be minimized.

[0232] The inner carrier (1210) 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 (1220). The x-axis, the y-axis, and the z-axis can be orthogonal to each other.

[0233] The inner carrier (1210) and the outer carrier (1220) can move integrally in the z-axis direction with respect to the fixed part (1100).

[0234] The inner carrier (1210) may include an electrode (1211). The electrode (1211) may be disposed on the surface of the inner carrier (1210). The electrode (1211) may be disposed on the lower surface of the inner carrier (1210). The electrode (1211) may be disposed on the outer surface of the inner carrier (1210). The electrode (1211) may be disposed on the outer circumferential surface of the inner carrier (1210). The electrode (1211) may be connected to the ground plate (1320). The electrode (1211) may be directly connected to the ground plate (1320). The electrode (1211) may be electrically connected to the ground plate (1320). The electrode (1211) may be a metal pattern. The electrode (1211) may be formed by plating a metal pattern on the surface of the inner carrier (1210), which is an injection-molded product.

[0235] Compared to the case where only the ground plate (1320) is present, when an electrode (1211) of the internal carrier (1210) is additionally formed, the electrostatic capacitance measured at the electrode (1311) of the substrate (1310) can increase. In this case, even when the electrostatic capacitance decreases due to movement of the internal carrier (1210) and the ground plate (1320), the measurement of the electrostatic capacitance can be facilitated.

[0236] The electrode (1211) may include a plurality of electrodes. The electrode (1211) may include four electrodes. The electrode (1211) may include first to fourth electrodes. The electrode (1211) may include first to fourth electrodes corresponding to the first to fourth electrodes (1311-1, 1311-2, 1311-3, 1311-4).

[0237] The inner carrier (1210) may include a protrusion (1212). The protrusion (1212) may be formed on the lower surface of the inner carrier (1210). The protrusion (1212) may protrude downward from the inner carrier (1210). The protrusion (1212) may protrude from the lower surface of the inner carrier (1210). A ground plate (1320) may be coupled to the protrusion (1212). The ground plate (1320) may be bonded to the lower surface of the protrusion (1212).

[0238] The inner carrier (1210) may include a protrusion (1213). The protrusion (1213) may be a stopper. The protrusion (1213) may be formed on an outer surface of the inner carrier (1210). The protrusion (1213) may protrude outward from the inner carrier (1210). The protrusion (1213) may be positioned in a groove (1224) of the outer carrier (1220).

[0239] The force-torque sensor may include an outer carrier (1220). The moving part (1200) may include the outer carrier (1220). The outer carrier (1220) may be disposed between the inner carrier (1210) and the fixed part (1100). The outer carrier (1220) may be disposed on the outside of the inner carrier (1210). The outer carrier (1220) may be disposed within the fixed part (1100). The outer carrier (1220) may be disposed on the fixed part (1100). The outer carrier (1220) may be disposed within the base (1110). The outer carrier (1220) may move in the z-axis direction with respect to the fixed part (1100). The outer carrier (1220) may move together with the inner carrier (1210) when the inner carrier (1210) moves in the z-axis direction.

[0240] The outer carrier (1220) may include an electrode (1221). The electrode (1221) may be disposed on the surface of the outer carrier (1220). The electrode (1221) may be disposed on the lower surface of the outer carrier (1220). The electrode (1221) may be disposed on the inner peripheral surface of the outer carrier (1220). The electrode (1221) may be disposed on the outer surface of the outer carrier (1220). The electrode (1221) may be a metal pattern. The electrode (1221) may be formed by plating a metal pattern on the surface of the outer carrier (1220), which is an injection-molded product.

[0241] Compared to the case where only the ground plate (1320) is present, when an electrode (1221) of an external carrier (1220) is additionally formed, the electrostatic capacitance measured at the electrode (1311) of the substrate (1310) can increase. In this case, even when the electrostatic capacitance decreases due to movement of the internal carrier (1210), the external carrier (1220), and the ground plate (1320), the measurement of the electrostatic capacitance can be facilitated.

[0242] The electrode (1221) may include a plurality of electrodes. The electrode (1221) may include four electrodes. The electrode (1221) may include first to fourth electrodes. The electrode (1221) may include first to fourth electrodes corresponding to the first to fourth electrodes (1311-1, 1311-2, 1311-3, 1311-4).

[0243] The outer carrier (1220) may include a first groove (1222). The first groove (1222) may be an internal ball rail. A first ball (1510) may be disposed in the first groove (1222). The first ball (1510) may move along the first groove (1222). Alternatively, the first ball (1510) may rotate while at least a portion of the first ball (1510) is accommodated in the first groove (1222).

[0244] The outer carrier (1220) may include a second groove (1223). The second groove (1223) may be an external ball rail. A second ball (1520) may be placed in the second groove (1223). The second ball (1520) may move along the second groove (1223). The second groove (1223) may extend in the z-axis direction.

[0245] The outer carrier (1220) may include a groove (1224). The groove (1224) may be formed on the inner surface of the outer carrier (1220). The groove (1224) may be formed concavely on the inner surface of the outer carrier (1220). The protrusion (1213) of the inner carrier (1210) may be arranged in the groove (1224) of the outer carrier (1220).

[0246] The groove (1224) can limit the movement of the inner carrier (1210) within a preset range. When the inner carrier (1210) rotates about the z-axis by a preset angle or more with respect to the outer carrier (1220), the protrusion (1213) of the inner carrier (1210) can come into contact with the groove (1224) of the outer carrier (1220).

[0247] The outer carrier (1220) may include a protrusion (1225). The protrusion (1225) may be a stopper. The protrusion (1225) may be formed on an outer surface of the outer carrier (1220). The protrusion (1225) may protrude outwardly from the outer carrier (1220). The protrusion (1225) may be positioned in a groove (1112) of the fixing member (1100).

[0248] The outer carrier (1220) may include a protrusion (1226). The protrusion (1226) may be formed on the lower surface of the outer carrier (1220). The protrusion (1226) may protrude downward from the outer carrier (1220). The protrusion (1226) may protrude from the lower surface of the outer carrier (1220).

[0249] The force-torque sensor may include a lead (1230). The moving part (1200) may include the lead (1230). The lead (1230) may be connected to an internal carrier (1210). At least a portion of the lead (1230) may be disposed on a base (1110). At least a portion of the lead (1230) may be disposed on an upper cover (1120). At least a portion of the lead (1230) may be disposed on a fixed part (1100). At least a portion of the lead (1230) may protrude beyond the fixed part (1100). An external force may be applied to at least a portion of the lead (1230) that protrudes beyond the fixed part (1100). The external force may be applied to the lead (1230). The lead (1230) may be moved by the external force. The lead (1230) may be coupled to the internal carrier (1210). The lead (1230) can be placed on the inner carrier (1210). The lead (1230) can be placed on the inner carrier (1210). The lead (1230) can move integrally with the inner carrier (1210). The lead (1230) can be fixed to the inner carrier (1210). At least a portion of the lead (1230) can be exposed outside the fixing member (1100). The lead (1230) can be exposed to the outside and move by an external force.

[0250] When a force is applied to the lead (1230) 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 (1210) can move with respect to the external carrier (1220). When a force is applied to the lead (1230) in the direction of the third axis, the internal carrier (1210) and the external carrier (1220) can move together with respect to the fixed part (1100). 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.

[0251] The force-torque sensor may include a detection unit (1300). The detection unit (1300) may detect movement of the moving unit (1200) with respect to the fixed unit (1100). The detection unit (1300) may detect movement of the moving unit (1200) with respect to the fixed unit (1100) in the x-axis direction. The detection unit (1300) may detect movement of the moving unit (1200) with respect to the fixed unit (1100) in the y-axis direction. The detection unit (1300) may detect movement of the moving unit (1200) with respect to the fixed unit (1100) in the yaw direction. The detection unit (1300) may detect movement of the moving unit (1200) with respect to the fixed unit (1100) in the pitch direction. The detection unit (1300) can detect the roll direction movement of the moving unit (1200) with respect to the fixed unit (1100). The detection unit (1300) can detect the z-axis direction movement of the moving unit (1200) with respect to the fixed unit (1100).

[0252] The detection unit (1300) may include detection cells. The detection unit (1300) may include a plurality of detection cells. The detection unit (1300) may include four detection cells. The detection unit (1300) may include first to fourth detection cells (1300-1, 1300-2, 1300-3, 1300-4).

[0253] Each of the first to fourth sensing cells (1300-1, 1300-2, 1300-3, 1300-4) can independently sense electrostatic capacitance. Through this, the yaw direction, pitch direction, roll direction, and z-axis direction movements of the moving part (1200) can be separately detected.

[0254] The first sensing cell (1300-1) may include a first electrode (1311-1) and a first ground plate (1320-1). The second sensing cell (1300-2) may include a second electrode (1311-2) and a second ground plate (1320-2). The third sensing cell (1300-3) may include a third electrode (1311-3) and a third ground plate (1320-3). The fourth sensing cell (1300-4) may include a fourth electrode (1311-4) and a fourth ground plate (1320-4).

[0255] The force-torque sensor may include a substrate (1310). The sensing unit (1300) may include the substrate (1310). The substrate (1310) may be placed on the fixing unit (1100). The substrate (1310) may be placed on the lower cover (1130). The substrate (1310) may be placed on the base (1110).

[0256] The substrate (1310) may include an electrode (1311). The electrode (1311) may be formed on a surface of the substrate (1310). The electrode (1311) may be a positive electrode. The electrode (1311) may be formed of metal.

[0257] The electrode (1311) may include a first portion (1311a). The first portion (1311a) may be disposed on the upper surface of the substrate (1310). The first portion (1311a) may correspond to the wing portion (1321) of the ground plate (1320).

[0258] The electrode (1311) may include a second portion (1311b). The second portion (1311b) may extend from the first portion (1311a). The second portion (1311b) may be arranged on the inner surface of the groove (1312) of the substrate (1310). The second portion (1311b) may correspond to the protrusion (1322) of the ground plate (1320). The second portion (1311b) may be in a bent form from the first portion (1311a).

[0259] The second part (1311b) may be connected to the first part (1311a). Alternatively, the second part (1311b) and the first part (1311a) may be separated from each other. This allows the capacitance of the first part (1311a) and the capacitance of the second part (1311b) to be measured separately.

[0260] The electrode (1311) may include a plurality of electrodes. The electrode (1311) may include four electrodes. The electrode (1311) may include first to fourth electrodes (1311-1, 1311-2, 1311-3, 1311-4). The first to fourth electrodes (1311-1, 1311-2, 1311-3, 1311-4) may correspond to the first to fourth ground plates (1320-1, 1320-2, 1320-3, 1320-4).

[0261] The substrate (1310) may include a groove (1312). A protrusion (1322) of a ground plate (1320) may be positioned in the groove (1312). The groove (1312) may be formed by an outer surface of the circular substrate (1310) being inwardly depressed. The groove (1312) may be formed with a width greater than the thickness of the protrusion (1322). The protrusion (1322) may be movable within the groove (1312).

[0262] Home (1312) may include multiple homes. Home (1312) may include four homes. Home (1312) may include first to fourth homes.

[0263] The substrate (1310) may include a ground terminal. A ground plate (1320) may be coupled to the ground terminal. Through this, noise in the electrostatic capacity detected by the detection unit (1300) may be eliminated.

[0264] The substrate (1310) may include an upper surface facing the moving part (1200). A first region (1313) and a second region (1314) in which no electrode (1311) is disposed may be formed on the upper surface of the substrate (1310).

[0265] The first region (1313) may be formed in the central region of the upper surface of the substrate (1310), which is circular when viewed from above. An electrode (1311) may not be formed in the first region (1313). A ground terminal may be formed in the first region (1313). A second connecting portion (1324) of a ground plate (1320) may be connected to the first region (1313).

[0266] The second region (1314) may extend radially from the first region (1313). An electrode (1311) may not be formed in the second region (1314). A conductive line of the substrate (1310) may be arranged in the second region (1314). For example, a conductive line for connecting a ground terminal to the outside may be arranged in the second region (1314).

[0267] The second region (1314) may include multiple second regions. The second region (1314) may include four second regions. The second regions (1314) may be arranged symmetrically around the first region (1313).

[0268] The force-torque sensor may include a ground plate (1320). The sensing unit (1300) may include the ground plate (1320). At least a portion of the ground plate (1320) may be movable integrally with the inner carrier (1210). The ground plate (1320) may be formed as a separate member and bonded to the inner carrier (1210) with an adhesive. The ground plate (1320) may be disposed on the inner carrier (1210). The ground plate (1320) may be coupled to the inner carrier (1210). The ground plate (1320) may be fixed to the inner carrier (1210).

[0269] The ground plate (1320) may include a plurality of ground plates. The ground plate (1320) may include four ground plates. The ground plate (1320) may include first to fourth ground plates (1320-1, 1320-2, 1320-3, 1320-4). The ground plate (1320) may include first to fourth ground plates (1320-1, 1320-2, 1320-3, 1320-4) corresponding to the first to fourth electrodes (1311-1, 1311-2, 1311-3, 1311-4).

[0270] The ground plate (1320) may include a wing portion (1321). The wing portion (1321) may face the first portion (1311a) of the electrode (1311). The wing portion (1321) may be spaced apart from the first portion (1311a) of the electrode (1311). The wing portion (1321) may be positioned at a position corresponding to the first portion (1311a) of the electrode (1311). The wing portion (1321) may overlap the first portion (1311a) of the electrode (1311) in the z-axis direction. The wing portion (1321) may face the first portion (1311a) of the electrode (1311) with an air gap therebetween. As a variation, an elastic dielectric may be placed between the wing portion (1321) and the first portion (1311a) of the electrode (1311).

[0271] The ground plate (1320) may include a protrusion (1322). At least a portion of the protrusion (1322) may be disposed in a groove (1312) of the substrate (1310). At least a portion of the protrusion (1322) may be inserted into the groove (1312) of the substrate (1310). The protrusion (1322) may be bent from the wing (1321). The protrusion (1322) may extend downward from the wing (1321). At least a portion of the protrusion (1322) may overlap the substrate (1310) in a direction perpendicular to the z-axis.

[0272] The protrusion (1322) may face the second part (1311b) of the electrode (1311). The protrusion (1322) may be spaced apart from the second part (1311b) of the electrode (1311). The protrusion (1322) may be positioned at a position corresponding to the second part (1311b) of the electrode (1311). The protrusion (1322) may overlap the second part (1311b) of the electrode (1311) in a direction perpendicular to the z-axis. The protrusion (1322) may face the second part (1311b) of the electrode (1311) with an air gap therebetween. As a variation, a dielectric having elasticity may be disposed between the protrusion (1322) and the second part (1311b) of the electrode (1311).

[0273] The ground plate (1320) may include a first coupling portion (1323). The first coupling portion (1323) may be coupled to the inner carrier (1210).

[0274] The ground plate (1320) may include a second coupling portion (1324). The second coupling portion (1324) may be coupled to the substrate (1310). The second coupling portion (1324) may be coupled to a ground terminal of the substrate (1310).

[0275] The ground plate (1320) may include a connecting portion (1325). The connecting portion (1325) may connect the first connecting portion (1323) and the second connecting portion (1324). The connecting portion (1325) may be bent. The connecting portion (1325) may include a shape that is bent multiple times. The connecting portion (1325) may include a bent portion. The connecting portion (1325) may include a plurality of strands. The connecting portion (1325) may be deformable. Through this, the second connecting portion (1324) is fixed to the substrate (1310) and the first connecting portion (1323) can move together with the internal carrier (1210). That is, the connecting portion (1325) can connect the first connecting portion (1323) and the second connecting portion (1324) so ​​that the first connecting portion (1323) can move relative to the second connecting portion (1324).

[0276] The ground plate (1320) may include a hole (1325a). The connecting portion (1325) may include a hole (1325a). The hole (1325a) may be formed between the first connecting portion (1323) and the second connecting portion (1324). The hole (1325a) may include a plurality of holes. The connecting portion (1325) may be formed into a plurality of strands by the plurality of holes. The elasticity of the connecting portion (1325) may be adjusted through the shape of the hole (1325a).

[0277] The force-torque sensor may include an elastic member (1400). The elastic member (1400) may be coupled to an inner carrier (1210) and an outer carrier (1220). The elastic member (1400) may be coupled to an upper portion of the inner carrier (1210). The elastic member (1400) may be coupled to an upper surface of the inner carrier (1210). The elastic member (1400) may be coupled to an upper portion of the outer carrier (1220). The elastic member (1400) may be coupled to an upper surface of the outer carrier (1220).

[0278] The elastic member (1400) can press the inner carrier (1210) toward the outer carrier (1220) so that the first ball (1510) is in close contact with the inner carrier (1210) and the outer carrier (1220). When the elastic member (1400) is assembled, the elasticity of the elastic member (1400) can be used to press the inner carrier (1210) toward the outer carrier (1220). At this time, the inner carrier (1210) can press the first ball (1510) so that the first ball (1510) is in close contact with the inner carrier (1210) and the outer carrier (1220).

[0279] The elastic member (1400) may be a spring. The elastic member (1400) may be formed of metal. The elastic member (1400) may have elasticity.

[0280] The elastic member (1400) may include an inner portion (1410). The inner portion (1410) may be coupled to an inner carrier (1210). The inner portion (1410) may be disposed on the inner carrier (1210). The inner portion (1410) may be fixed to the inner carrier (1210). The inner portion (1410) may be coupled to an upper surface of the inner carrier (1210). The inner portion (1410) may be disposed on an upper surface of the inner carrier (1210). The inner portion (1410) may be fixed to an upper surface of the inner carrier (1210).

[0281] The elastic member (1400) may include an outer portion (1420). The outer portion (1420) may be coupled to an outer carrier (1220). The outer portion (1420) may be disposed on the outer carrier (1220). The outer portion (1420) may be fixed to the outer carrier (1220). The outer portion (1420) may be coupled to an upper surface of the outer carrier (1220). The outer portion (1420) may be disposed on an upper surface of the outer carrier (1220). The outer portion (1420) may be fixed to an upper surface of the outer carrier (1220).

[0282] The elastic member (1400) may include a connecting portion (1430). The connecting portion (1430) may connect the inner portion (1410) and the outer portion (1420). The connecting portion (1430) may elastically connect the inner portion (1410) and the outer portion (1420). The connecting portion (1430) may have elasticity. The connecting portion (1430) may have restoring force. The connecting portion (1430) may include a bent shape. The connecting portion (1430) may be formed by being bent multiple times. The connecting portion (1430) may include a bent portion.

[0283] The force-torque sensor may include a guide member. The guide member may guide the movement of the moving part (1200). The guide member may guide the movement of the moving part (1200) relative to the fixed part (1100). The guide member may guide the movement of the inner carrier (1210) relative to the outer carrier (1220).

[0284] The force-torque sensor may include a first ball (1510). The guide member may include the first ball (1510). The first ball (1510) may be disposed between the inner carrier (1210) and the outer carrier (1220). The first ball (1510) may guide movement of the inner carrier (1210) with respect to the outer carrier (1220). The inner carrier (1210) may move in the yaw direction, the pitch direction, and the roll direction with respect to the outer carrier (1220) by the first ball (1510). However, when the inner carrier (1210) is to move in the z-axis direction, the first ball (1510) and the outer carrier (1220) may move together with the inner carrier (1210). The first ball (1510) may include a plurality of balls.

[0285] The force-torque sensor may include a second ball (1520). The guide member may include the second ball (1520). The second ball (1520) may be disposed between the outer carrier (1220) and the fixing member (1100). The second ball (1520) may be disposed between the outer carrier (1220) and the base (1110). The second ball (1520) may guide movement of the outer carrier (1220) with respect to the base (1110). The outer carrier (1220) may move in the z-axis direction with respect to the base (1110) by the second ball (1520). At this time, the outer carrier (1220) may move together with the inner carrier (1210) and the lead (1230).

[0286] The second ball (1520) may include multiple balls. The second ball (1520) may include at least two balls that overlap in the z-axis direction. Even when the external carrier (1220) moves by at least two balls that overlap in the z-axis direction, tilt can be prevented.

[0287] 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.

[0288] The force-torque sensor may include an upper coupling member (1610). The upper coupling member (1610) may be coupled to a lead (1230) and an inner carrier (1210). The upper coupling member (1610) may secure the lead (1230) to the inner carrier (1210).

[0289] The force-torque sensor may include a lower coupling member (1620). The lower coupling member (1620) may be coupled to a lower cover (1130) and a base (1110). The lower coupling member (1620) may secure the lower cover (1130) to the base (1110).

[0290] The force-torque sensor may include an outer coupling member (1630). The outer coupling member (1630) may be coupled to the upper cover (1120) and the base (1110). The outer coupling member (1630) may secure the upper cover (1120) to the base (1110).

[0291]

[0292] Hereinafter, the operation of a force-torque sensor according to a second embodiment of the present invention will be described with reference to the drawings.

[0293] FIG. 40 is a diagram for explaining a case where an external force having a yaw or pitch direction component is applied to a force-torque sensor according to a second embodiment of the present invention. FIG. 41 is a diagram for explaining a change when an external force having a roll direction component is applied to a force-torque sensor according to a second embodiment of the present invention. FIG. 42 is a diagram for explaining a case where an external force having a z-axis direction component is applied to a force-torque sensor according to a second embodiment of the present invention.

[0294] 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 (1230) of the force-torque sensor according to the second embodiment of the present invention, the lead (1230) can rotate or tilt around the x-axis (see yaw in FIG. 40). At this time, at least a part of the internal carrier (1210) and the ground plate (1320) can move integrally with the lead (1230) (see A, B in FIG. 40). Meanwhile, since the fixed part (1100) is maintained in a fixed state, the distance between the electrode (1311) of the substrate (1310) placed on the fixed part (1100) and the ground plate (1320) can be changed. For example, the capacitance measured in the first sensing cell (1300-1) and the second sensing cell (1300-2) may decrease, and the capacitance measured in the third sensing cell (1300-3) and the fourth sensing cell (1300-4) may increase. Through this, the y-axis component and the y-axis component of the external force applied to the lead (1230) may be measured.

[0295] 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 (1230) of the force-torque sensor according to the second embodiment of the present invention, the lead (1230) can be rotated or tilted around the y-axis. At this time, at least a part of the internal carrier (1210) and the ground plate (1320) can move integrally with the lead (1230) (see A and B of FIG. 40). Meanwhile, since the fixed part (1100) is maintained in a fixed state, the distance between the electrode (1311) of the substrate (1310) placed on the fixed part (1100) and the ground plate (1320) can be changed. For example, the capacitance measured in the second sensing cell (1300-2) and the third sensing cell (1300-3) may decrease, and the capacitance measured in the first sensing cell (1300-1) and the fourth sensing cell (1300-4) may increase. Through this, the x-axis direction component and the pitch direction component of the external force applied to the lead (1230) may be measured.

[0296] When an external force having a roll direction component is applied to the lead (1230) of the force-torque sensor according to the second embodiment of the present invention, the lead (1230) can rotate or tilt around the z-axis (see roll in FIG. 41). At this time, at least a part of the internal carrier (1210) and the ground plate (1320) can move integrally with the lead (1230) (see a, b in FIG. 41). Meanwhile, since the fixed part (1100) is maintained in a fixed state, the distance between the electrode (1311) of the substrate (1310) placed on the fixed part (1100) and the ground plate (1320) can be changed. In particular, the distance between the protrusion (1322) of the ground plate (1320) and the second part (1311b) of the electrode (1311) of the substrate (1310) can be changed. Accordingly, the electrostatic capacitance measured in the first to fourth sensing cells (1300-1, 1300-2, 1300-3, 1300-4) may all increase or all decrease. However, the change in the electrostatic capacitance in the first part (1311a) of the electrode (1311) may be absent or minimal, and the change in the electrostatic capacitance in the second part (1311b) of the electrode (1311) may be large. Through this, the force in the roll direction component of the external force applied to the lead (1230) may be measured.

[0297] When an external force having a z-axis component is applied to the lead (1230) of the force-torque sensor according to the second embodiment of the present invention, the lead (1230) can move along the z-axis (see B of FIG. 42). At this time, at least a portion of the outer carrier (1220), the inner carrier (1210), and the ground plate (1320) can move integrally with the lead (1230) (see A and B of FIG. 42). Meanwhile, since the fixed portion (1100) is maintained in a fixed state, the distance between the electrode (1311) of the substrate (1310) disposed on the fixed portion (1100) and the ground plate (1320) can be changed. In particular, the distance between the wing portion (1321) of the ground plate (1320) and the first portion (1311a) of the electrode (1311) of the substrate (1310) can be changed. Accordingly, the capacitances measured in the first to fourth sensing cells (1300-1, 1300-2, 1300-3, 1300-4) may all increase or all decrease. However, the change in the capacitance in the first part (1311a) of the electrode (1311) may be large, and the change in the capacitance in the second part (1311b) of the electrode (1311) may be absent or minimal. Furthermore, since the distance between the electrode (1221) of the external carrier (1220) and the first part (1311a) of the electrode (1311) of the substrate (1310) also changes, the change in the capacitance in the first part (1311a) of the electrode (1311) may become larger. Through this, the force of the z-axis direction component of the external force applied to the lead (1230) can be measured.

[0298]

[0299] Below, the configuration of a robot according to a second embodiment of the present invention is described.

[0300] 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. A force-torque sensor according to a second embodiment of the present invention may be disposed on the gripping portion of the arm. The arm of the robot may include a joint. The force-torque sensor according to a second embodiment of the present invention may be disposed on a joint of the arm.

[0301]

[0302] 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 characteristics 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 fixed portion and including an electrode; a ground plate, at least a portion of which moves integrally with said moving part; and Including a first liquid and a second liquid disposed between the fixed part and the moving part, A force-torque sensor wherein the second liquid has a greater specific gravity than the first liquid.

2. In paragraph 1, A force-torque sensor wherein the second liquid has a lower dielectric constant than the first liquid.

3. In paragraph 1, The space between the fixed part and the moving part is sealed, A force-torque sensor in which the space between the fixed part and the moving part is filled with the first liquid and the second liquid.

4. In paragraph 1, A force-torque sensor in which the second liquid is disposed between the substrate and the ground plate in an up position where the substrate is placed below the ground plate.

5. In paragraph 1, A force-torque sensor in which the first liquid is disposed between the substrate and the ground plate in a down position where the substrate is placed on top of the ground plate.

6. In paragraph 1, A force-torque sensor in which the first liquid is placed in a part of the area between the substrate and the ground plate and the second liquid is placed in the remaining area, in a side position where the substrate and the ground plate are placed at the same height.

7. In paragraph 1, The above first liquid is water, The above second liquid is a force-torque sensor which is glycerin.

8. In paragraph 1, The above first liquid is water, The above second liquid is a force-torque sensor that is acetic acid.

9. In paragraph 1, The above first liquid is oil, The above second liquid is a force-torque sensor that is crude oil.

10. In paragraph 1, The above moving part includes an inner carrier and a lead coupled to the inner carrier and at least a portion of which is exposed to the outside, The above fixed part includes a base and a sealing cover coupled to the base, A force-torque sensor in which the sealing cover includes an outer portion coupled with the base, an inner portion in contact with the lead, a connecting portion connecting the outer portion and the inner portion, and a spring that presses the inner portion toward the lead.

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