A humanoid dexterous hand and humanoid robot

Abstract

The application discloses an anthropomorphic dexterous hand and an anthropomorphic robot, and the anthropomorphic dexterous hand comprises a palm structure, a plurality of finger structures and a touch sensing system, the palm structure is internally provided with a wire slot channel, each finger structure comprises a plurality of knuckles connected in series through a rotary joint, the knuckles are internally provided with knuckle inner cavity channels, the touch sensing system comprises a measuring sheet and a signal line, the measuring sheet is a stretchable sheet structure composed of a base layer, a pressure sensor array layer and a packaging protection layer, continuously spans the rotary joint and is laid on adjacent knuckles, a non-sensing elastic area is arranged in a joint-spanning area, the signal line is routed in the knuckle inner cavity channel with a redundant length, an additional wire length is reserved in a relaxed and curved form at the rotary joint, a distal knuckle palm side is divided into a high-density array area and a vector perception area, the high-density array area is provided with a sink array and an elastic protrusion, the vector perception area is provided with a blind hole and an elastic sealing plug, and the anthropomorphic robot comprises a robot body and the anthropomorphic dexterous hand.

Description

Technical Field

[0001] This invention relates to the field of humanoid robot technology, and in particular to a humanoid dexterous hand and a humanoid robot. Background Technology

[0002] In the field of humanoid robots, when performing grasping operations, humanoid dexterous hands need to sense the contact pressure distribution of each contact area of ​​the hand in real time in order to determine the grasping state and adjust the grasping force. Existing humanoid dexterous hands generally use rigid or semi-rigid sensor sheets to cover the palmar side of the knuckles and lay signal lines along the knuckles to realize contact pressure sensing.

[0003] In the prior art, rigid or semi-rigid sensor sheets are difficult to adapt to the curvature of the knuckle when the finger is bent, which causes the sensor sheet to lift, wrinkle or detach from the knuckle surface in the joint movement area, forming a sensing blind zone. When the humanoid dexterous hand grasps the target object, the sensing blind zone in the joint movement area makes the sensing information of contact position, contact area and contact pressure distribution inaccurate, affecting the stability and reliability of the grasping operation.

[0004] The signal lines laid across the joints are subjected to concentrated stress during repeated bending of the fingers, which can easily lead to fatigue breakage and signal transmission interruption. Once the signal lines break, the tactile signals cannot be transmitted to the acquisition device normally, and the tactile perception function of the humanoid dexterous hand will be completely lost.

[0005] The distal phalanges of the humanoid dexterous hand have a small radius of curvature and gradually thinner walls. The usable area on the palmar side is only one-third to one-quarter of the usable area on the palmar side of the proximal phalanx. When performing precision assembly operations, this area needs to acquire high spatial resolution normal pressure distribution in the periphery of the fingertip to perceive the contact contour and pose of tiny parts. It also needs to acquire the three-dimensional contact force vector of normal force and biaxial tangential force at the most frequently contacted position in the center of the fingertip to determine the direction and magnitude of the part's alignment deviation. If the piezoresistive measuring plate is directly used to cover the distal phalanx, the thinner wall of the distal phalanx will limit the usable space. Moreover, the piezoresistive sensor pixel array can only perceive normal pressure and lacks the ability to perceive tangential force, making it impossible to determine the direction and magnitude of the part's alignment deviation. These defects result in incomplete perception information of the contact contour, pose, and alignment deviation direction of the target part when the humanoid dexterous hand performs precision assembly operations at the fingertips, affecting the stability and reliability of the grasping operation. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is that the human hand tactile perception coverage is incomplete, the signal line is prone to fatigue and breakage, and the fingertip precision operation lacks three-dimensional force direction perception.

[0007] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a humanoid dexterous hand and a humanoid robot, comprising:

[0008] The palm-shaped structure has internal slots for accommodating signal lines.

[0009] Multiple finger-like structures, each comprising multiple phalanges connected in series, adjacent phalanges being connected by a rotary joint, and each phalange having an internal cavity channel for accommodating signal line routing.

[0010] The tactile system includes a measuring sheet and signal lines. The measuring sheet is a stretchable thin sheet structure composed of three layers: a base layer, a pressure sensor array layer, and an encapsulation protective layer. The measuring sheet is laid across the joints of two adjacent knuckles in a cross-joint laying manner. The cross-joint area has a non-sensing elastic region where no sensing pixels are arranged. The signal lines are routed in a redundant length manner within the cavity channels of each knuckle, and an additional line length is reserved in a relaxed bending shape at each joint.

[0011] Each distal phalanx of the finger-like structure has a fingertip tactile structure on its palmar side. The palmar side of the distal phalanx is divided into a high-density array area and a vector sensing area. The high-density array area has a countersunk hole array and elastic protrusions embedded in the opening of each countersunk hole. The vector sensing area has blind holes and elastic sealing plugs embedded in the blind holes.

[0012] In a preferred embodiment of the humanoid dexterous hand described in this invention: the base layer is a stretchable elastic film, the pressure sensor array layer forms row electrodes and column electrodes arranged perpendicularly to each other on a flexible substrate, and a pressure-sensitive resistor material is provided at each intersection node to form a sensing pixel, and the encapsulation protective layer covers the outside of the pressure sensor array layer to encapsulate the pressure sensor array layer.

[0013] In a preferred embodiment of the humanoid dexterous hand described in this invention: the measuring pieces are respectively laid on the palm side and back side of the palmar structure of the simulated hand and the palmar side of the proximal and middle phalanges of each simulated finger structure. The base layer of the measuring piece is bonded and fixed to the mounting base with adhesive, and the edge of the measuring piece is sealed with sealant.

[0014] In a preferred embodiment of the humanoid dexterous hand described in this invention: the countersunk hole is a conical blind hole with an opening diameter larger than the bottom diameter. The axis of the countersunk hole is perpendicular to the tangential plane of the distal phalanx fingertip. Each countersunk hole has a magnetic focusing sleeve made of a soft magnetic alloy film on its inner wall. The magnetic focusing sleeve surrounds the inner wall of the countersunk hole to form a conical magnetic circuit channel that gradually narrows from the opening to the bottom. The elastic protrusion has permanent magnet particles that are magnetized along the axis of the countersunk hole evenly dispersed inside. The elastic protrusion is fitted into the opening of the countersunk hole through an interference fit with the inner wall of the countersunk hole. A Hall effect sensor is installed at the bottom of each countersunk hole. The sensing axis of the Hall effect sensor is installed along the axis of the corresponding countersunk hole.

[0015] In a preferred embodiment of the humanoid dexterous hand described in this invention: a magnetic isolation groove is provided in the distal phalanx wall between adjacent countersunk holes. The magnetic isolation groove is an annular groove surrounding the outer periphery of a single countersunk hole, penetrating the soft magnetic alloy thin film layer, and is filled with a non-magnetic polymer material.

[0016] In a preferred embodiment of the humanoid dexterous hand described in this invention: the blind hole is formed by two orthogonal rectangular long grooves intersecting at the center, the long axes of the two rectangular long grooves are arranged along the width and length directions of the distal phalanx, respectively, the cross-shaped planar contour of the elastic sealing plug matches the opening of the blind hole, the four arm ends of the elastic sealing plug are respectively inserted into the four groove ends of the blind hole, a cross-shaped sealed air pressure cavity is formed between the bottom surface of the elastic sealing plug and the bottom surface of the blind hole, and the elastic sealing plug achieves radial sealing through the interference fit between its outer peripheral surface and the side wall of the blind hole.

[0017] In a preferred embodiment of the humanoid dexterous hand described in this invention: each of the four slot ends of the bottom surface of the blind hole is provided with an isolation rib. The isolation rib protrudes from the bottom surface of the blind hole to contact the bottom surface of the elastic sealing plug, dividing the cross-shaped sealed air pressure chamber into four independent sector microcavities. The four sector microcavities correspond to the positive and negative ends in the width direction and the positive and negative ends in the length direction of the distal phalanx, respectively. Each of the four sector microcavities has an independent micro air channel at its bottom. Each micro air channel is equipped with an air pressure sensor. The distal ends of the four micro air channels are closed ends, and each micro air channel is only connected to the corresponding sector microcavity.

[0018] In a preferred embodiment of the humanoid dexterous hand described in this invention: the micro airway is connected by a flexible tube when crossing each rotation joint, and the two ends of the flexible tube are respectively sealed and connected to the rigid airway section in the inner cavity of the adjacent phalanx through a plug-in quick connector, and the flexible tube is reserved with bending allowance at the rotation joint.

[0019] In a preferred embodiment of the humanoid dexterous hand described in this invention: an isolation groove is provided between the high-density array area and the vector sensing area. The isolation groove is an annular groove surrounding the outer periphery of the blind hole, and the groove is filled with a non-magnetic and airtight polymer material.

[0020] A humanoid robot includes a robot body and a humanoid dexterous hand mounted at the end of the robot body, the humanoid dexterous hand serving as the end effector of the humanoid robot.

[0021] The beneficial effects of this invention are as follows: by constructing the measuring sheet as a stretchable thin sheet structure composed of three layers: a base layer, a pressure sensor array layer, and an encapsulation protective layer, and by using a cross-joint laying method to continuously lay the measuring sheet across the joint area on adjacent phalanges, the measuring sheet can stretch and deform accordingly when the phalanges are bent without lifting, wrinkling, or detaching from the phalange surface. A non-sensing elastic area with only an elastic layer and no sensing pixels is set in the cross-joint area to ensure that the measuring sheet remains in close contact with the phalange surface at each finger bending angle, thereby eliminating the sensing blind spot in the phalange activity area and achieving complete coverage of all contact surfaces of the hand.

[0022] By reserving extra line length in a relaxed bending shape at each rotation joint of the intracavitary channel of each finger joint, the signal line can be stretched without being excessively stretched when the finger joint is bent. This effectively disperses the concentrated stress of the signal line during repeated bending, thereby avoiding the problem of signal line breakage due to fatigue accumulation and ensuring reliable transmission of tactile signals throughout the entire finger movement process.

[0023] By incorporating countersunk holes with magnetic focusing sleeves within a high-density array region on the palmar side of the distal phalanx, the weak magnetic flux resulting from the reduction in the total number of permanent magnet particles due to the thinning of the distal phalanx wall is amplified and concentrated into the effective detection range of the Hall effect sensor, thus solving the problem of insufficient magnetic flux intensity in the thin-walled region of the fingertip. Furthermore, by machining magnetically insulating grooves penetrating a soft magnetic alloy thin film layer between adjacent countersunk holes, the magnetic circuits of each magnetic focusing sleeve are completely isolated, eliminating asymmetric magnetic crosstalk caused by the small curvature geometry of the fingertip surface. This ensures that each sensing location possesses independent and consistent magnetic flux characteristics, achieving high spatial resolution normal pressure sensing in the peripheral region. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein:

[0025] Figure 1 This is a schematic diagram of the overall structure of the humanoid dexterous hand of the present invention;

[0026] Figure 2 This is a schematic diagram of the internal structure of the humanoid dexterous hand of the present invention;

[0027] Figure 3 This is a cross-sectional structural diagram of the humanoid dexterous hand of the present invention;

[0028] Figure 4 This is a frontal view schematic diagram of the distal phalanx tactile sensor of the present invention;

[0029] Figure 5 This is a schematic cross-sectional view of the countersunk hole in the high-density array region of the present invention.

[0030] Figure 6 This is a schematic cross-sectional view of the blind hole in the vector sensing area of ​​the present invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0032] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0033] like Figure 1 As shown, according to an embodiment of this invention, a humanoid dexterous hand is provided, including at least a palm-like structure 1, five finger-like structures, and a tactile system. The palm-like structure 1 serves as the mounting base for each finger-like structure. Its main frame is plate-shaped, and mounting base surfaces are provided on the palm side and the back of the palm, respectively. A wire groove channel 15 extending along the inner cavity of the frame is provided inside the palm-like structure 1. The wire groove channel 15 is a long strip-shaped cavity extending from the root of the finger to the root of the palm, used to accommodate and constrain the signal line 12. A cable outlet 13 is provided on the back of the palm side of the palm-like structure 1. A rubber sheath 14 is provided at the cable outlet 13 to prevent the signal line 12 from being damaged by friction.

[0034] Five proto-finger structures correspond to the thumb, index finger, middle finger, ring finger, and little finger, respectively, arranged sequentially from the little finger side to the thumb side along the base of the proto-palm structure 1. The proto-finger structures of the index, middle, ring, and little fingers are each composed of three segments connected in series: the proximal phalanx 2, the middle phalanx 3, and the distal phalanx 4. Adjacent segments are connected by a rotational joint 5. The rotation axis of the rotational joint 5 extends along the width of the palm, allowing adjacent segments to rotate relative to each other in a plane formed by the thickness of the palm and the length of the fingers, thus replicating the bending and extending movements of human fingers. The proximal ends of each proximal phalanx 2 are connected to the proto-palm via a metacarpophalangeal joint 6. Structure 1 is connected, and the metacarpophalangeal joint 6 has at least two degrees of freedom, which respectively realize the bending and extension movement and the lateral abduction and retraction movement of the fingers. The thumb-like finger structure is composed of two phalanges connected in series, the proximal phalanx 2 and the distal phalanx 4. The thumb base is provided with a carpal joint, which has the degree of freedom of opposition movement to reproduce the opposition function of the human thumb. The main body of each phalanx is tubular, and the palmar side is a convex arc surface structure that conforms to the shape of the human finger. Each phalanx has an internal cavity channel 16 that runs through the main body of the phalanx. The internal cavity channel 16 is a circular or elliptical cross-section through hole that extends along the length of the phalanx to accommodate the signal line 12.

[0035] like Figure 3 As shown, each simulated finger structure is equipped with a set of tendon cable drive units. One end of the tendon cable 7 is fixed to the palmar end of the distal phalanx 4, and the other end extends into the simulated palm structure 1 through the guide pulley 8 installed at each rotation joint 5. It is connected to the output shaft of the micro servo motor 9 fixed in the simulated palm structure 1 near the palm root area. The axis of the guide pulley 8 is installed along the width of the palm to guide the tendon cable 7 to change its routing direction at the joint. When the output shaft of the micro servo motor 9 rotates, it drives the tendon cable 7 to tighten or loosen, thereby controlling the bending angle of each phalanx. Each simulated finger structure is also equipped with a return spring 10. The return spring 10 is installed on the back side of each rotation joint 5, and its two ends are respectively fixed to the back wall of two adjacent phalanxes. When the micro servo motor 9 releases the tension of the tendon cable 7, the elastic restoring force of the return spring 10 drives each phalanx to rotate in the extension direction, realizing the active extension movement of the finger.

[0036] The tactile sensing system includes at least a measuring plate 11, a signal line 12, and a data acquisition device;

[0037] Structure and laying method of measuring piece 11:

[0038] The measuring sheet 11 is a stretchable and bendable thin sheet structure, composed of three composite layers: a base layer, a pressure sensor array layer, and an encapsulation protective layer.

[0039] The substrate layer is a stretchable elastic film with sufficient flexibility and elastic recovery properties, capable of adapting to the bending of the knuckle and restoring its original shape after stretching. The pressure sensor array layer is integrated between the substrate layer and the encapsulation protective layer. Row and column electrodes are formed on a flexible polyimide substrate using screen printing or inkjet printing processes. The row and column electrodes are arranged perpendicularly to each other. A piezoresistive material is placed at each intersection node to form a single sensing pixel. Each sensing pixel can independently sense the normal contact pressure at its location. The center-to-center distance between adjacent sensing pixels is no more than 10 mm. The encapsulation protective layer covers the outside of the pressure sensor array layer, encapsulating the pressure sensor array layer as a whole to prevent the intrusion of external liquids and dust, while also providing buffer protection for the pressure sensor array layer.

[0040] In some embodiments, the base layer and the encapsulation protective layer are silicone rubber films, the base layer has a thickness of 0.3 mm to 0.5 mm, the encapsulation protective layer has a thickness of 0.2 mm to 0.3 mm, and the overall thickness of the measuring piece 11 is no more than 1.5 mm;

[0041] In some embodiments, the center-to-center spacing between adjacent sensing pixels is 5 mm to achieve higher spatial resolution within the effective sensing area.

[0042] like Figure 2 As shown, the measuring pieces 11 are laid and fixed on the palm and back of the palm of the simulated hand structure 1, as well as the palmar side of the proximal phalanx 2 and the middle phalanx 3 of each simulated finger structure. The base layer of the measuring piece 11 is bonded and fixed to the mounting base with medical grade silicone adhesive. The edges of the measuring piece 11 are sealed with silicone sealant to prevent the edges from lifting or peeling.

[0043] For the joint movement area, the measuring piece 11 adopts a cross-joint laying method, that is, the measuring piece 11 is continuously laid across the joint area on two adjacent joints. Utilizing the high elongation characteristics of the base layer material, the measuring piece 11 stretches along with the joint without breaking or detaching from the joint surface. In the cross-joint area, the measuring piece 11 has non-sensor elastic areas on both sides of the joint. No sensing pixels are arranged in the non-sensor elastic areas, and only the base layer and the encapsulation protective layer are retained to adapt to the stretching deformation requirements under the maximum bending angle of the finger.

[0044] like Figure 4As shown, each of the finger-like structures has a fingertip tactile structure on the palmar side of the distal phalanx 4, which replaces the measuring piece 11 to realize the tactile perception function of the palmar side of the distal phalanx 4. The palmar side of the distal phalanx 4 is divided into two functional areas: a high-density array area 17 and a vector sensing area 18. The high-density array area 17 covers the peripheral area of ​​the contact surface of the distal phalanx 4, and the vector sensing area 18 occupies the most frequently contacted position in the center of the contact surface of the distal phalanx 4. The two functional areas are spatially complementary and together cover the palmar contact surface of the distal phalanx 4.

[0045] Within the high-density array region 17, an array of countersunk holes 19 is machined along the normal direction of the fingertip surface of the distal phalanx 4. Each countersunk hole 19 is a conical blind hole with an opening diameter larger than its bottom diameter. The opening diameter is 1.5mm to 2.5mm, and the bottom diameter is reduced to 0.6mm to 1.0mm. The cone angle of the countersunk hole 19 matches the local curvature of the fingertip surface, so that the axis of each countersunk hole 19 is always perpendicular to the tangent plane of the fingertip surface.

[0046] like Figure 5 As shown, a soft magnetic alloy film is electroplated on the inner wall of each countersunk hole 19 to form a magnetic focusing sleeve 20. The wall thickness of the magnetic focusing sleeve 20 is 0.05mm to 0.15mm. The magnetic focusing sleeve 20 surrounds the inner wall of the countersunk hole 19 to form a tapered magnetic circuit channel that gradually narrows from the opening end to the bottom. This constrains and converges the divergent magnetic flux generated by the elastic protrusion 21 to the small cross-section end at the bottom of the countersunk hole 19, so that the magnetic flux density at the sensing surface of the Hall effect sensor 22 at the bottom is increased by 3 to 5 times compared with the case without the magnetic focusing sleeve 20. This amplifies the weak magnetic flux caused by the reduction in the total amount of permanent magnet particles due to the thinning of the wall thickness of the distal phalanx 4 to the effective detection range.

[0047] An elastic protrusion 21 is embedded at the opening end of each countersunk hole 19. The shape of the elastic protrusion 21 is a truncated cone that matches the opening of the countersunk hole 19. The large end face faces outward to form a tactile contact surface, and the small end face faces the bottom of the countersunk hole 19. Neodymium iron boron permanent magnet particles are uniformly dispersed inside the elastic protrusion 21. Before the elastic protrusion 21 is solidified, the neodymium iron boron permanent magnet particles are oriented magnetized by an axial magnetic field so that the remaining magnetization direction is arranged along the axis of the countersunk hole 19. The elastic protrusion 21 is embedded at the opening end of the countersunk hole 19 through the interference fit between the elastic material itself and the inner wall of the countersunk hole 19. When subjected to normal contact pressure, it is compressed along the axis of the countersunk hole 19. After the pressure is released, it automatically resets by the elastic restoring force of the elastic material.

[0048] A Hall effect sensor 22 is installed at the bottom of each countersunk hole 19. The sensing axis of the Hall effect sensor 22 is installed along the axial direction of the corresponding countersunk hole 19. It is used to detect the change in axial magnetic flux density caused by the neodymium iron boron permanent magnet particles moving towards the bottom when the elastic protrusion 21 is compressed by normal contact pressure, and thus sense the normal pressure value at the contact position.

[0049] In the wall of the distal phalanx 4 between adjacent countersunk holes 19, a magnetic isolation groove 23 is machined along the tangential direction of the curved surface. The magnetic isolation groove 23 is an annular groove surrounding the outer periphery of a single countersunk hole 19, penetrating the soft magnetic alloy thin film layer to completely isolate the magnetic circuit of each magnetic cluster sleeve 20 from the magnetic circuit of the adjacent countersunk hole 19, eliminating asymmetric magnetic crosstalk caused by the small curvature surface geometry of the fingertip. The magnetic isolation groove 23 is filled with non-magnetic polymer material.

[0050] like Figure 6 As shown, a blind hole 24 is machined in the vector sensing area 18 along the normal direction of the curved surface. The blind hole 24 is formed by two orthogonal rectangular long slots intersecting at the center. The long axes of the two rectangular long slots are arranged along the width direction of the distal phalanx 4 and the length direction of the distal phalanx 4, respectively. The length of each rectangular long slot is 2.5mm to 3.5mm and the width is 1mm to 1.5mm.

[0051] An elastic sealing plug 25 is installed at the center of the blind hole 24. The cross-shaped planar contour of the elastic sealing plug 25 matches the opening of the blind hole 24. The four arm ends of the elastic sealing plug 25 are respectively inserted into the four groove ends of the blind hole 24. A cross-shaped sealed air pressure cavity is formed between the bottom surface of the elastic sealing plug 25 and the bottom surface of the blind hole 24. The top surface of the elastic sealing plug 25 is flush with or slightly higher than the opening end of the blind hole 24, forming the tactile contact surface of the vector sensing area 18. The elastic sealing plug 25 achieves radial sealing through the interference fit between its outer peripheral surface and the side wall of the blind hole 24. At the same time, elastic sealant is coated between the outer peripheral surface of the elastic sealing plug 25 and the side wall of the blind hole 24 to enhance air tightness. When the elastic sealing plug 25 is subjected to normal force, it is compressed as a whole along the axis of the blind hole 24. When subjected to tangential force, it is deflected and deformed in the blind hole 24. After the force is released, it automatically resets by the elastic restoring force of the elastic material itself.

[0052] An isolation rib 26 is provided at each of the four slot ends on the bottom surface of the blind hole 24. The isolation rib 26 protrudes from the bottom surface of the blind hole 24 toward the elastic sealing plug 25 until it contacts the bottom surface of the elastic sealing plug 25, dividing the cross-shaped sealed air pressure chamber into four independent sector microcavities 27. The four sector microcavities 27 correspond to the positive and negative ends of the blind hole 24 along the width direction of the distal phalanx 4 and the positive and negative ends along the length direction of the distal phalanx 4, respectively, so that each sector microcavity 27 can independently reflect the volume change in the corresponding direction.

[0053] Each of the four sector microcavities 27 has an independent micro airway 28 at its bottom. The four micro airways 28 run along the inner cavity of the distal phalanx 4, and extend through the phalanx inner cavity channel 16 of the middle phalanx 3 and the proximal phalanx 2 to the interior of the palm-like structure 1. Each micro airway 28 is equipped with a pressure sensor 29, which is fixed to the inner wall of the distal phalanx 4 near the airway entrance of the corresponding sector microcavity 27. The distal ends of the four micro airways 28 are closed ends, that is, each micro airway 28 is only connected to the corresponding sector microcavity 27 and is not connected to the external atmosphere, thus forming a closed pressure detection circuit.

[0054] It should be noted that the miniature airway 28 uses a flexible tube connection method when crossing each rotation joint 5. The two ends of the flexible tube are respectively sealed and connected to the rigid airway section in the inner cavity of the adjacent phalanx through plug-in quick connectors. The flexible tube is reserved with bending allowance at the joint to adapt to the relative displacement at the joint caused by the bending movement of the finger, so as to ensure the airtightness and unobstructed flow of the airway throughout the entire finger movement process.

[0055] An isolation groove 30 is fabricated between the blind hole 24 in the vector sensing area 18 and the countersunk hole 19 array in the high-density array area 17. The isolation groove 30 is an annular groove surrounding the outer periphery of the blind hole 24. The groove is filled with a non-magnetic and airtight polymer material, which isolates the high-density array area 17 and the vector sensing area 18 from each other at both the magnetic circuit and air circuit levels. This eliminates the interference of magnetic leakage from the magnetic focusing sleeve 20 on the air pressure microcavity and the influence of air pressure fluctuations on the magnetic circuit, ensuring that the two sensing principles work independently and are not coupled to each other.

[0056] To prevent the signal wire 12 from fatigue breaking due to concentrated pulling during repeated bending of the knuckles, the signal wire 12 is routed with redundant length within the intra-knuckle cavity channel 16 of each knuckle: at each rotation joint 5, the signal wire 12 is accommodated in a relaxed curved shape within the intra-knuckle cavity channel 16 of the rotation joint 5, reserving extra wire length so that the signal wires 12 at both ends of the rotation joint 5 can be stretched without being excessively stretched when the finger is bent. The signal wire 12 is laid along the dorsal side of each simulated finger structure and converges in the wire groove channel 15 inside the simulated palm structure 1. Then, the signal line 12 extends to the acquisition device via the cable outlet 13. The row and column electrodes of the measuring piece 11 are electrically connected by thermoforming or anisotropic conductive film technology. The signal leads of each Hall effect sensor 22 and the signal leads of the four barometric pressure sensors 29 converge along the inner cavity of the distal phalanx 4 to the flexible circuit board 31. Then, the signal line 12, which is routed with redundant length at the rotary joint 5, converges in the wire groove channel 15 inside the palm-like structure 1, and extends to the acquisition device via the cable outlet 13.

[0057] In some embodiments, the signal line 12 is in the form of a flexible flat cable or a flexible printed circuit.

[0058] The acquisition device synchronously acquires and processes the sensing signals of all measuring pieces 11 and the fingertip tactile structure. The acquisition device includes a multiplexing circuit, a signal conditioning circuit, an analog-to-digital converter, and a microcontroller. The multiplexing circuit uses a row and column scanning method to sequentially select and read each sensing pixel in the pressure sensor array layer. The signal conditioning circuit amplifies and filters the resistance change signal output by each sensing pixel. The analog-to-digital converter converts the analog sensing signal into a digital quantity and transmits it to the microcontroller. The microcontroller integrates the pressure data of all sensing pixels into a pressure distribution map that represents the spatial distribution of contact pressure in each area in matrix form, and outputs the pressure distribution map to the upper control system through the communication interface.

[0059] The acquisition device simultaneously receives magnetic flux density signals from each Hall effect sensor 22 in the high-density array area 17 and air pressure signals from four air pressure sensors 29 in the vector sensing area 18. For the high-density array area 17, the acquisition device converts the magnetic flux density change value output by each Hall effect sensor 22 into the normal pressure value of the corresponding tactile position according to the pre-calibrated mapping relationship between magnetic flux density and normal pressure, and generates an outer normal pressure distribution map.

[0060] For the vector sensing area 18, the acquisition device performs vector calculations on the air pressure values ​​of the four sector microcavities 27. (Normal force component) The change is proportional to one-quarter of the sum of the pressure values ​​of the four sector microcavities, i.e.:

[0061]

[0062] in, , , , These represent the air pressure values ​​within the four sector microcavities 27 along the positive and negative ends of the width direction of the distal phalanx 4, and along the positive and negative ends of the length direction of the distal phalanx 4. This represents the change relative to the initial state.

[0063] Tangential force component along the width direction of distal phalanx 4 The change in pressure between the two opposing sectors of the microcavity 27 in the width direction is proportional to the change in air pressure, i.e.:

[0064]

[0065] Tangential force component along the length of distal phalanx 4 The change in pressure between the two opposing sectors of the microcavity 27 along the length direction is proportional to the change in air pressure, i.e.:

[0066]

[0067] The acquisition device converts each component into a force value according to a pre-calibrated mapping relationship, thus obtaining the three-dimensional contact force vector at the center position. The acquisition device fuses the peripheral normal pressure distribution map with the three-dimensional force vector data at the center position, and together with the pressure distribution maps of the proximal phalanx 2 and the middle phalanx 3, outputs them to the upper control system in real time via the communication interface.

[0068] This embodiment also provides a humanoid robot, which includes at least a robot body and the aforementioned humanoid dexterous hand installed at the end of the robot body. The humanoid dexterous hand serves as the end effector of the humanoid robot and, in conjunction with the motion control system and perception processing system of the robot body, enables operational functions with comprehensive tactile perception capabilities.

[0069] When in use, the humanoid dexterous hand performs a grasping operation. The output shaft of the micro servo motor 9 rotates to tension the tendon rope 7. After the tendon rope 7 changes direction through the guide pulleys 8 at each rotation joint 5, it pulls the palmar end of the distal phalanx 4 to bend towards the palm. The middle phalanx 3 and proximal phalanx 2 bend in conjunction through the rotation joint 5. Each finger gathers towards the palm to wrap around the target object. When the micro servo motor 9 rotates in the opposite direction to release the tension of the tendon rope 7, the return spring 10 on the back of each rotation joint 5 drives each phalanx to rotate back in the extension direction, and the fingers return to the extended state.

[0070] During the grasping process, the tactile system continuously senses the contact state. The multi-channel selection circuit of the acquisition device sequentially selects each sensing pixel in the pressure sensor array layer of each measuring piece 11 in the proximal phalanx 2, middle phalanx 3, and palm-like structure 1 area in a row and column scanning manner. The signal conditioning circuit amplifies and filters the resistance change signal output by each sensing pixel to eliminate common-mode noise and high-frequency interference. The analog-to-digital converter converts the processed analog signal into a digital quantity. The microcontroller performs zero-point calibration on the digital quantity to eliminate the zero bias error introduced by installation stress and temperature drift. Based on the pre-calibrated pressure and resistance characteristic relationship, the resistance change of each sensing pixel is converted into the corresponding contact pressure value. Then, the pressure values ​​of all sensing pixels are integrated into a pressure distribution map and uploaded to the upper control system in real time through the communication interface.

[0071] When the elastic protrusion 21 of the high-density array region 17 is subjected to normal contact pressure, the elastic protrusion 21 is compressed along the axial direction of the counterbore 19, and the internal neodymium iron boron permanent magnet particles move closer to the bottom of the counterbore 19 as a whole, and the axial magnetic flux density increases accordingly. The magnetic focusing sleeve 20 confines and focuses the magnetic flux to the sensing surface of the bottom Hall effect sensor 22. The Hall effect sensor 22 outputs the corresponding magnetic flux density change signal. The acquisition device converts the signal into a normal pressure value according to the calibration mapping relationship, and collects the pressure values ​​of each sensing position to generate an outer normal pressure distribution map.

[0072] When the elastic sealing plug 25 of the vector sensing area 18 is subjected to a normal force, the elastic sealing plug 25 is compressed as a whole along the axis of the blind hole 24, the volume of the four sector microcavities 27 decreases synchronously, and the air pressure values ​​detected by the four air pressure sensors 29 increase synchronously. The air pressure difference between the two opposing sectors in the width direction and the air pressure difference between the two opposing sectors in the length direction are both approximately zero. The acquisition device extracts the normal force component by summation operation. When the elastic sealing plug 25 is subjected to a tangential force along the width direction of the distal phalanx 4, the elastic sealing plug 25 deviates and deforms in the direction of the force within the blind hole 24. The volume of the microcavity 27 in the sector on the force side decreases and the air pressure increases, while the volume of the microcavity 27 in the opposite sector on the force side increases and the air pressure decreases. The air pressure difference between the two opposite sectors changes significantly, and the acquisition device extracts the tangential force component through differential calculation. tangential force component along the length of distal phalanx 4 The extraction principle and Similarly, after the three components are transformed by the calibration mapping relationship, the three-dimensional contact force vector at the center position is obtained;

[0073] Based on the real-time received pressure distribution map and fingertip tactile data, the upper-level control system performs grasping control in four stages: contact detection, contact area calculation, grasping force control, and slip detection.

[0074] Contact detection phase: When the humanoid dexterous hand approaches the target object, the upper control system continuously monitors the pressure value of all sensor pixels. When the pressure value of any sensor pixel exceeds the preset contact detection threshold, it is determined that the area has made contact with the target object, triggering the subsequent control process.

[0075] Contact area calculation stage: The upper control system counts the number of sensor pixels whose pressure values ​​exceed the contact detection threshold, and estimates the current contact area by combining the center distance between adjacent sensor pixels. The grasping stability is judged by monitoring the changing trend of the contact area.

[0076] Grasping force control stage: The upper control system sums the pressure values ​​of all contact sensor pixels to obtain the total contact force. Based on the deviation between the real-time value of the total contact force and the target grasping force, the output force of each micro servo motor 9 of the finger-like structure is adjusted through the control algorithm to achieve closed-loop control of the grasping force.

[0077] Slip detection stage: The upper control system calculates the rate of change of pressure value of each sensor pixel between adjacent sampling times. When the number of sensor pixels whose rate of change of pressure value exceeds the slip judgment threshold exceeds the preset ratio, it is determined that the target object has slipped, and force boosting control is immediately triggered to suppress the slipping.

[0078] When performing precision fingertip assembly operations, the upper-level control system, based on the above four-stage control process, further utilizes the peripheral normal pressure distribution map to perform part contact contour recognition and pose estimation, and utilizes the central three-dimensional force vector to perform alignment deviation direction judgment and precision insertion force control, thus collaboratively realizing full-process perception and control of precision fingertip operations.

[0079] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A humanoid dexterous hand, characterized in that: include: The palm-shaped structure has internal slots for accommodating signal lines. Multiple finger-like structures, each including multiple phalanges connected in series, adjacent phalanges are connected by a rotary joint, and each phalange has an internal cavity channel for accommodating signal line routing. The tactile system includes a measuring sheet and signal lines. The measuring sheet is a stretchable thin sheet structure composed of three layers: a base layer, a pressure sensor array layer, and an encapsulation protective layer. The measuring sheet is laid across the joints of two adjacent knuckles in a cross-joint laying manner. The cross-joint area has a non-sensing elastic region where no sensing pixels are arranged. The signal lines are routed in a redundant length manner within the cavity channels of each knuckle, and an additional line length is reserved in a relaxed bending shape at each joint. Each distal phalanx of the finger-like structure has a fingertip tactile structure on its palmar side. The palmar side of the distal phalanx is divided into a high-density array area and a vector sensing area. The high-density array area has a countersunk hole array and elastic protrusions embedded in the opening of each countersunk hole. The vector sensing area has blind holes and elastic sealing plugs embedded in the blind holes.

2. The anthropomorphic dexterous hand according to claim 1, characterized in that: The substrate layer is a stretchable elastic film. The pressure sensor array layer forms row electrodes and column electrodes arranged perpendicularly to each other on a flexible substrate. A pressure-sensitive resistor material is set at each intersection node to form a sensing pixel. The encapsulation protective layer covers the outside of the pressure sensor array layer to encapsulate the pressure sensor array layer.

3. The anthropomorphic dexterous hand according to claim 2, characterized in that: The measuring pieces are respectively laid on the palm side and back side of the palm structure of the simulated hand, as well as the palmar side of the proximal and middle phalanges of each simulated finger structure. The base layer of the measuring piece is bonded and fixed to the mounting base with adhesive, and the edge of the measuring piece is sealed with sealant.

4. The anthropomorphic dexterous hand according to claim 1, characterized in that: The countersunk hole is a conical blind hole with an opening diameter larger than the bottom diameter. The axis of the countersunk hole is perpendicular to the tangent plane of the distal phalanx fingertip. Each countersunk hole has a magnetic focusing sleeve made of a soft magnetic alloy film on its inner wall. The magnetic focusing sleeve surrounds the inner wall of the countersunk hole to form a conical magnetic circuit channel that gradually narrows from the opening to the bottom. The elastic protrusion has permanent magnet particles that are magnetized along the axis of the countersunk hole evenly dispersed inside. The elastic protrusion is fitted into the opening of the countersunk hole through an interference fit with the inner wall of the countersunk hole. A Hall effect sensor is installed at the bottom of each countersunk hole. The sensing axis of the Hall effect sensor is installed along the axis of the corresponding countersunk hole.

5. The anthropomorphic dexterous hand according to claim 4, characterized in that: A magnetic isolation groove is provided in the wall of the distal phalanx between adjacent countersunk holes. The magnetic isolation groove is an annular groove that surrounds the outer periphery of a single countersunk hole and penetrates the soft magnetic alloy thin film layer. The magnetic isolation groove is filled with a non-magnetic polymer material.

6. The anthropomorphic dexterous hand according to claim 1, characterized in that: The blind hole is formed by two orthogonal rectangular long grooves intersecting at the center. The long axes of the two rectangular long grooves are arranged along the width and length directions of the distal phalanx, respectively. The cross-shaped planar profile of the elastic sealing plug matches the opening of the blind hole. The four arm ends of the elastic sealing plug are respectively inserted into the four groove ends of the blind hole. A cross-shaped sealed air pressure cavity is formed between the bottom surface of the elastic sealing plug and the bottom surface of the blind hole. The elastic sealing plug achieves radial sealing through the interference fit between its outer peripheral surface and the side wall of the blind hole.

7. The anthropomorphic dexterous hand according to claim 6, characterized in that: Each of the four slots on the bottom surface of the blind hole is provided with an isolation rib. The isolation rib protrudes from the bottom surface of the blind hole and contacts the bottom surface of the elastic sealing plug, dividing the cross-shaped sealed air pressure chamber into four independent sector microcavities. The four sector microcavities correspond to the positive and negative ends in the width direction and the positive and negative ends in the length direction of the distal phalanx, respectively. Each of the four sector microcavities has an independent micro air channel at its bottom. A pressure sensor is installed on each micro air channel. The distal ends of the four micro air channels are closed ends, and each micro air channel is only connected to the corresponding sector microcavity.

8. The anthropomorphic dexterous hand according to claim 7, characterized in that: The micro airway is connected by a flexible tube when crossing each rotation joint. The two ends of the flexible tube are respectively sealed and connected to the rigid airway section in the inner cavity of the adjacent phalanx through plug-in quick connectors. The flexible tube is reserved with bending allowance at the rotation joint.

9. The anthropomorphic dexterous hand according to claim 4, characterized in that: An isolation groove is provided between the high-density array area and the vector sensing area. The isolation groove is an annular groove surrounding the outer periphery of the blind hole, and the groove is filled with a non-magnetic and airtight polymer material.

10. A humanoid robot, characterized in that, The robot includes a robot body and a humanoid dexterous hand as described in any one of claims 1 to 9, which is mounted at the end of the robot body and serves as the end effector of the humanoid robot.

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