A rope-driven high-finger-tip-force high-joint-stiffness dexterous hand

Abstract

The present application relates to the field of robot technology, and more particularly to a rope-driven high-finger-tip-force high-joint-stiffness dexterous hand. The technical scheme comprises a forearm shell, a five-finger multi-joint skeleton, a plurality of actuator units arranged in the forearm shell, and a plurality of tendon ropes connecting the actuator units and the finger joints. An integrated mechanism is arranged between each two adjacent finger joints of the five-finger multi-joint skeleton. The present application realizes high finger-tip-force output, high joint stiffness, low transmission error, adaptive gripping and online health monitoring and analysis of the rope-driven dexterous hand without increasing the diameter of the tendon rope and the volume of the finger joint, through the integrated gear rolling joint, the embedded angle-dependent variable high-rope-drive tension amplification mechanism, the full-length fiber Bragg grating strain monitoring and the dual-mode redundant sensing.

Description

Technical Field

[0001] This invention relates to the field of robotics, and more particularly to a rope-driven dexterous hand with high fingertip force and high joint stiffness. Background Technology

[0002] Rope-driven multi-finger dexterous hands place the drive unit at the rear of the forearm, remotely driving each finger joint via tendon cords across the wrist joint. This significantly reduces the rotational inertia of the end effector and facilitates the integration of multiple degrees of freedom. However, traditional rope-driven dexterous hands often suffer from inherent deficiencies in fingertip force. For example, the commercially available rope-driven dexterous hand "Shadow Hand" has a maximum fingertip force of only 10 N, resulting in weak load capacity. The "Min rope-driven anthropomorphic hand" uses universal joints and rope transmission for lightweight adaptive grasping, but its fingertip force is only 6 N, limiting its practicality. The "DLR hand" increases joint size to improve torque, achieving a fingertip force of up to 30 N, but its overall size is 1.5 times that of an adult hand, making it bulky. Furthermore, traditional hinge joints suffer from insufficient rigidity and are subject to sliding friction and pin wear, leading to gaps and tension losses over long-term use. The core technical challenge currently facing rope-driven dexterous hands is how to simultaneously achieve high fingertip force, high rigidity of multiple joints, compact integration between joints, and online health monitoring and analysis during dexterous hand movement, all within the constraints of unchanged tendon cord diameter and finger joint volume.

[0003] To address the aforementioned issues, existing solutions have proposed improvements such as gear rolling joints, tension amplification via fixed / moving pulley systems, variable transmission ratios on the actuator side, or chord kinematic measurement. However, these solutions often assemble the gear joint and tension amplification mechanism as two independent parts, leading to accumulated tolerances and excessive space occupation. Furthermore, most solutions rely on series elastic elements or use a fixed amplification ratio, failing to meet the angle adaptation requirement of "low lever arm before contact and high lever arm after gripping." Additionally, the gear rolling joints suffer from weak stiffness and insufficient cable-driven fingertip force output, while lacking online monitoring methods for the entire length strain and health status of the chords. Therefore, this application proposes a cable-driven dexterous hand with high fingertip force and high joint stiffness. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the background art by proposing a rope-driven dexterous hand with high fingertip force and high joint stiffness.

[0005] The technical solution of the present invention: a rope-driven dexterous hand with high fingertip force and high joint stiffness, comprising a forearm shell, a five-finger multi-joint skeleton, a plurality of actuator units disposed within the forearm shell, and a plurality of tendon ropes connecting the actuator units to each finger joint; an integrally formed mechanism is provided between every two adjacent finger joints of the five-finger multi-joint skeleton, the outer edge of the integrally formed mechanism being toothed, and forming pure rolling contact with the corresponding toothed contours on the adjacent finger joints to form a joint;

[0006] The integral molding mechanism has two concentric wheel sets embedded inside. The outer diameter wheel of the concentric wheel set is used for winding the tendon rope, and the inner diameter wheel is used to connect the phalanx via a connecting rod. The effective radius of the outer diameter wheel is... With the effective radius of the inner diameter wheel The ratio constitutes the tension amplification factor And the tension amplification rate It is the joint angle Preset differentiable functions This causes the tension of the tendon rope to increase. Mechanically magnified Apply the double dose to the knuckle;

[0007] The tendon cord is a braided cord with at least one fiber Bragg grating embedded inside, and the fiber Bragg grating is used to measure the strain distribution along the entire length of the tendon cord in real time.

[0008] Optionally, the tension amplification rate The value range is [1.5, 5].

[0009] Optionally, the function The constant is a constant. .

[0010] Optionally, the function ,in , The constant is preset so that the tension amplification rate increases monotonically as the joint flexion angle increases.

[0011] Optionally, the integrally molded mechanism is manufactured by SLM titanium alloy or SLA photopolymerization 3D printing, with enhanced joint rigidity, and its tooth surface is honed to a certain surface roughness. And its modulus Pressure angle Tooth width Pitch circle radius Number of teeth The transmission ratio error is ≤ ±0.5%.

[0012] Optionally, the tooth profile is any one of an involute tooth profile, a Bezier tooth profile, or a non-circular pitch circle tooth profile;

[0013] A MEMS accelerometer or acoustic emission sensor is placed near each joint to monitor and analyze energy changes in the 5-20 kHz frequency band during gear meshing. .

[0014] Optionally, a MEMS microphone is provided at the span of the tendon ligament to pick up the fundamental frequency of the tendon ligament's lateral vibration. And through the string vibration formula Inversely, the tension of the tendon ligament, The chord tension is calculated using the string vibration method. The length of the free span of the tendon ligament. The linear density of the tendon ligament;

[0015] Optionally, the five-finger multi-joint skeleton has a total of 20 joints and 15 active degrees of freedom, wherein the distal interphalangeal joints of the four fingers are driven joints and are empirically coupled to the corresponding proximal interphalangeal joints; a six-dimensional force / torque sensor is provided at each fingertip.

[0016] The tendon cord has a diameter of 0.4 mm and a maximum working tension of 80 N; the maximum fingertip force for each finger is 24 N.

[0017] Optionally, the outer side of the forearm housing is provided with a removable ETFE, FEP, or PFA chemical splash guard, which is connected to the dexterous hand body via an alignment pin and a torque limiting locking element, wherein the torque limiting locking element limits the torque of the dexterous hand body. ;

[0018] The forearm housing contains 15 actuator units, each of which includes a hollow cup brushless motor or servo motor, a planetary reducer, and a tendon cable reel.

[0019] Optionally, the fiber Bragg grating fiber is provided with multiple grating segments along the entire length of the tendon, each grating segment being 2 mm long and spaced 5-30 mm apart; when the tension is pushed back by the fiber Bragg grating... The tension inversely inferred by the MEMS microphone through string vibration satisfy Furthermore, when the duration exceeds three flexion-extension cycles, a dual-modal consistent contradictory health alarm is output to indicate local fiber rupture in the tendon chord; the ends of the fiber Bragg gratings are connected to the FBG demodulation unit via an FC / PC connector, and then the strain of each grating segment is transmitted via a CAN-FD or EtherCAT bus. Tension in reverse propagation with fiber Bragg grating Output to the automatic control unit.

[0020] Compared with the prior art, this application includes at least one of the following beneficial technical effects:

[0021] The tension amplification mechanism is embedded in the joint and integrally formed with the gear, so that the tension of the tendon rope is amplified and applied to the knuckle, thereby increasing the output force of the fingertip without increasing the diameter of the tendon rope or the volume of the knuckle.

[0022] Gears use pure rolling contact to replace hinge sliding, eliminating sliding friction between the pin and bushing and the resulting clearance, thus reducing tension loss and hysteresis during joint transmission.

[0023] The one-piece molding mechanism integrates the gear joint with the tension amplification mechanism, increasing joint stiffness, eliminating tolerance accumulation caused by component assembly, and controlling transmission ratio error.

[0024] The fiber Bragg grating is embedded in the entire length of the tendon chord to measure the strain distribution along the entire length of the tendon chord in real time, and can identify local fiber damage, wear and chemical erosion.

[0025] The tension amplification rate changes continuously with the joint angle, achieving an adaptive transition from low amplification rate before contact to high amplification rate after gripping, achieving both smooth fit and high-rigidity grip without switching control laws.

[0026] MEMS accelerometers monitor the energy of gear meshing impact frequency bands, while MEMS microphones infer tendon tension through string vibrations. The two sensing paths are redundant, supporting joint and tendon ligament failure detection and health self-sensing analysis.

[0027] This invention achieves high fingertip force output, high joint stiffness, low transmission error, adaptive grip, and online health monitoring and analysis in a rope-driven dexterous hand without increasing the diameter of the tendon cord or the volume of the finger joint. This is achieved through an integrally molded gear rolling joint, an embedded angle-dependent variable tension amplification mechanism, full-length fiber Bragg grating strain monitoring, and dual-modal redundant sensing. Attached Figure Description

[0028] Figure 1 : A schematic diagram of the dexterous hand body structure provided in the embodiment of the present invention;

[0029] Figure 2 A diagram of a single finger structure, along the flexion and extension direction, showing the joints, tendon ligament winding path, concentric wheel assembly, and fingertip force sensor;

[0030] Figure 3 Exploded view of the integral molding mechanism of the single-piece printed gear and tension amplifier;

[0031] Figure 4 : Geometric diagram of tooth profile and pitch circle;

[0032] Figure 5 A. Cross-section of the fiber Bragg grating tendon; B. Longitudinal arrangement; C. Demodulation connection link.

[0033] Figure 6 Schematic diagram of the arrangement of a joint meshing impact MEMS accelerometer and a tendon chord vibration MEMS microphone;

[0034] Figure 7 Topology diagram of the forearm actuator assembly;

[0035] Figure 8 Schematic diagram of the interface between the chemical splash guard and the alignment pin / locking element.

[0036] Reference numerals: 1. Palm; 2. Knuckle; 3. Thumb; 4. Forearm shell; 10. Proximal knuckle; 11. MCP joint gear; 12. Tension amplification mechanism; 13. Outer diameter wheel; 14. Inner diameter wheel; 20. Middle knuckle; 21. PIP joint gear; 30. Distal knuckle; 31. DIP joint gear; 40. Cord; 40-1. Fiber Bragg grating fiber; 40-1a. FC / PC fiber optic connector; 40-2. Bragg grating segment ; 40-2-D, Fiber Optic Demodulation Unit; 40-2-M, Local MCU; 40-2-O, Bus Output Interface; 50, Six-Dimensional Force Sensor; 60, MEMS Accelerometer; 70, MEMS Microphone; 80, Actuator Unit; 80-1, Motor; 80-2, Planetary Gear Reducer; 80-3, Winding Reel; 90, Chemical Splash Protective Sheath; 91, Alignment Pin; 92, M2 Torque Limiting Locking Component; 93, Activated Carbon Filter Vent. Detailed Implementation

[0037] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0038] The present invention can be divided into the following seven serial links, and there are physical quantity transmission and state closed-loop feedback relationships between adjacent links.

[0039] The first stage involves the manufacturing and assembly of the integrally molded mechanism. For example... Figure 3 As shown, the articulated gear is formed in one step by SLM titanium alloy or SLA high-precision photopolymer 3D printing, and its tooth profile and the embedded concentric gear assembly are completed in the same process. The tooth surface is honed to a surface roughness Ra of no more than [value missing]. The transmission ratio error is controlled within ±0.5%, thereby eliminating the cumulative tolerance of component assembly.

[0040] The second step involves the principle of angle-dependent magnification. For example... Figure 4 As shown, the rim functions of the outer diameter wheel 13 and the inner diameter wheel 14 are denoted as follows: and Instantaneous magnification ,and It is a differentiable function of the joint angle θ. A typical functional form is: When the joint flexion angle That is, when the finger is extended and in the initial contact position, the magnification is... It provides a lower magnification to ensure a smooth fit to the object; when That is, when the finger is fully flexed, the magnification is... It provides a high magnification to output high grip strength.

[0041] The third stage involves chord drive and force transmission. The actuator unit, via the reel, cassette, concentric pulley assembly, and connecting rod, geometrically amplifies the tension T of the chord 40 into a joint driving force. ,and The force is ultimately output to knuckle 2. The entire force transmission link does not depend on any displacement-compensating elastic element connected in series with the chord.

[0042] The fourth step is fiber Bragg grating strain monitoring. For example... Figure 5 As shown, several 2 mm long Bragg grating segments 40-2 are evenly distributed along the axial direction on the fiber Bragg grating fiber 40-1 embedded in the ultra-high molecular weight polyethylene braided tendon rope. The spacing between each grating segment is 5 mm to 30 mm. The sampling frequency of the fiber demodulation unit 40-2-D is not less than 1 kHz, and the local strain of each grating segment is measured in real time. and the corresponding tension When the strain difference in any segment exceeds a preset threshold, it is determined to be a local fiber fracture.

[0043] The fifth step is a dual-modal fusion assessment of chordae tendon health. Tension is determined by full-length strain back-propagation of the FBG. The tension derived from the string vibration formula of a MEMS microphone This results in two independent sampled values. The formula for string vibration is: ,in The free span length of the tendon ligament. For tendon cord linear density, This is the fundamental frequency of transverse vibration. When If the duration exceeds three flexion-extension cycles, it is determined to be a contradictory state caused by local fiber rupture of the tendon chord. At this time, the effective tension of the entire length decreases, but the local chord vibration shows no abnormality, and the system outputs a health alarm.

[0044] The sixth step involves monitoring and analyzing gear meshing impact and string vibration. For example... Figure 6 As shown, a MEMS accelerometer 60 is placed near each gear joint, with a sampling frequency of no less than 50 kHz, focusing on energy changes in the 5 kHz to 20 kHz frequency band. When the energy in this frequency band exceeds a preset baseline, the system outputs an alarm indicating abnormal gear wear or meshing failure.

[0045] The seventh step is chemical protection. For example... Figure 8As shown, the forearm housing 4 is covered by a removable chemical splash guard 90, made of ETFE, FEP, or PFA. The guard is connected to the body via a positioning pin 91 and a torque-limiting locking element, with a torque limit not exceeding 2 Nm, and can be repeatedly installed and removed at least 1000 times. The forearm housing also has an activated carbon filter vent for actively discharging chemical vapors.

[0046] The following three specific embodiments further illustrate the implementation of the present invention.

[0047] Example 1: Constant Magnification Example ;

[0048] like Figure 1 As shown, the rope-driven multi-joint high-tension, high-rigidity dexterous hand body of this embodiment includes a palm 1, five fingers, a thumb, and a forearm actuator assembly. The palm 1 has overall dimensions of 200 mm in length, 85 mm in width, and 30 mm in height, and is formed in one piece by selective laser sintering 3D printing from engineering resin, with a total weight of 650g. The forearm actuator assembly internally houses 15 servo motors or coreless brushless motors with planetary reducers. These actuator units are arranged in a 3-row, 5-column layout, as shown in the specific arrangement. Figure 7 As shown.

[0049] like Figure 2 As shown, the tendon cord 40 exits from the forearm cord exit hole, passes through the wrist cord organizer, enters the palm 1, and is then distributed to the tension amplification mechanism 12 embedded in each joint gear. The winding path of the tendon cord 40 is divided into six segments: the first segment is the forearm cord exit hole; the second segment is the wrist cord organizer; the third segment is the cord management groove in the palm 1; the fourth segment is the concentric wheel group embedded in the metacarpophalangeal joint, namely the outer diameter wheel 13 and the inner diameter wheel 14; the fifth segment is the concentric wheel group embedded in the proximal interphalangeal joint; the sixth segment is the empirical coupling of the distal interphalangeal joint, that is, passing through the proximal phalanx 10, the middle phalanx 20, and the distal phalanx 30 in sequence. Among them, the distal interphalangeal joints of the four fingers are driven joints and empirically coupled with the corresponding proximal interphalangeal joints, while the thumb is the active joint. One end of the proximal phalanx 10 is equipped with an MCP joint gear 11, a PIP joint gear 21 is set between the proximal phalanx 10 and the middle phalanx 20, and a DIP joint gear 31 is set between the middle phalanx 20 and the distal phalanx 30.

[0050] like Figure 3 As shown, the articulated gear is a one-piece molded mechanism, manufactured by SLM 3D printing of titanium alloy. The tooth surface is honed to a surface roughness Ra of no more than [value missing]. The module of the gear Pressure angle Tooth width Pitch circle radius Number of teeth The tooth profile adopts an involute tooth profile. Two concentric gear sets are embedded inside the part: the radius of the outer diameter gear 13... The diameter is 4.4 mm, used for winding the tendon cord 40; the radius of the inner diameter wheel 14 is... It is 1.5mm in diameter and connected to the distal phalanx via two connecting rods. In this embodiment, Divide by It is approximately equal to 2.93, which is close to 3. Therefore, the tension amplification factor is... It is always equal to a constant 3. The transmission ratio error is controlled within ±0.5%, and due to the adoption of a single-print structure, the accumulation of assembly tolerances is completely eliminated.

[0051] like Figure 4 As shown, part A is the pitch circle and concentric wheel assembly structure, and part B is the tension amplification function. Curve, magnification function in this embodiment It is always equal to 3, and is represented by a horizontal dashed line in the figure. The tendon rope 40 is made of ultra-high molecular weight polyethylene braided rope with a diameter of 0.4 mm. Its breaking load is not less than 250 N, the working tension range is 8N to 80 N, and the pretension is set at 15 N.

[0052] like Figure 5 As shown, part a is the cross-section, and part b is the longitudinal arrangement. A tendon cord 40 is embedded with a cord of 80 mm in diameter. The fiber Bragg grating fiber 40-1 has a core diameter of 9 mm. Several Bragg grating segments 40-2, each 2 mm long, are evenly distributed along the axial direction, with a grating spacing of 30 mm. The fiber optic end is connected to the fiber demodulation unit 40-2-D within the forearm via an FC / PC connector 40-1a. This demodulation unit includes an ASE broadband light source, an adjustable Fabry-Perot filter, an InGaAs photodetector, and a 16-bit analog-to-digital converter, with a sampling frequency of at least 1 kHz and a wavelength resolution of 1 pm. The demodulated wavelength array is converted into strain values ​​for each segment by the local MCU 40-2-M, using the following conversion formula: Subsequently, the strain gauges of each segment are transmitted via CAN-FD or EtherCAT bus 40-2-O. ,tension And health markers are output to control the cerebellum.

[0053] like Figure 6 As shown, a MEMS accelerometer 60 is placed near each joint gear, with a sampling frequency of no less than 50kHz, focusing on monitoring energy in the 5kHz to 20kHz frequency band. Simultaneously, a MEMS microphone 70 is placed at the span of the chord 40, specifically a 60mm free segment within the forearm, to pick up the fundamental frequency of the chord's lateral vibration. The local MCU uses the string vibration formula... ,in The free span length of the tendon ligament. For tendon cord linear density, The fundamental frequency of transverse vibration, where Take 0.06 m, The linear density is pre-calibrated. The MCU compares the tension calculated by the FBG in real time. Tension inversely related to string vibration ,when If the duration exceeds three flexion-extension cycles, it is determined to be a local fiber rupture of the tendon chordae, and a health alarm is output to the cerebellum to trigger the maintenance process.

[0054] like Figure 7 As shown, multiple actuator units 80 are arranged in a rectangular array inside the forearm housing 4. Each actuator unit 80 is equipped with a motor 80-1. The output shaft of the motor 80-1 is driven by a planetary reducer 80-2, and the planetary reducer 80-2 is driven by a winding reel 80-3 that is rotatably installed inside the forearm housing 4.

[0055] like Figure 8 As shown, the outer side of the main body is covered by a removable chemical splash shield 90, made of ETFE or FEP. The shield is quickly installed and removed via a positioning pin 91 and a torque-limiting locking element, with the torque limit not exceeding 2 Nm.

[0056] Example 2: Variable Angle Magnification Example .

[0057] This embodiment has the same basic structure as Embodiment 1, including a palm 1, five fingers, a thumb, and a forearm actuator assembly. The overall dimensions, manufacturing process, and overall weight of the palm 1, as well as the layout of the forearm actuator assembly, are the same as in Embodiment 1. Figure 1 and Figure 7 As shown.

[0058] like Figure 2 As shown, the winding path of the tendon cord 40 is also divided into six segments: from the cord exit hole in the forearm through the wrist cord organizer, the cord guide groove in the palm 1, then into the embedded concentric wheel group of the metacarpophalangeal joint and the proximal interphalangeal joint, and finally to the empirical coupling of the distal interphalangeal joint.

[0059] The main difference between this embodiment and Embodiment 1 lies in the rim shape design of the concentric wheel assembly. To achieve magnification that varies with the joint angle, the rims of the inner diameter wheel 14 and the outer diameter wheel 13 are designed as non-circular rims, so that the contact radius between the tendon ligament and the rim varies with the joint angle. Continuously changing. Specifically, the magnification function in this embodiment is: When the joint flexion angle That is, when the finger is extended and in the initial contact position, the magnification is... At this point, a lower magnification is provided to ensure a smooth fit to the object; when That is, when the finger is fully flexed, the magnification is... This provides a higher magnification to achieve a stronger grip. The function curve is as follows: Figure 4 As shown by the solid line in the image.

[0060] The profile function of a non-circular rim is expressed by the following closed-form expression: inner diameter and wheel radius. ,in Take 4.5 mm; outer diameter wheel radius It remains constant, meaning it does not change with θ. The non-circular rim is manufactured using SLA high-precision photopolymer 3D printing, with the rim curve function integrally formed with other features of the part. Other parameters of the articulated gear include the module. Pressure angle Tooth width Pitch circle radius Number of teeth The involute tooth profile is the same as in Example 1. The tooth surface is also honed to a surface roughness Ra of no more than 0.4. The transmission ratio error is controlled within ±0.5%.

[0061] In this embodiment, the tendon cord 40 also uses a 0.4 mm diameter ultra-high molecular weight polyethylene braided cord with a breaking load of not less than 250 N, a working tension of 8 N to 80 N, and a pretension of 15 N. For example... Figure 5 As shown, a diameter [missing information] is embedded inside the tendon cord. The fiber Bragg grating fiber 40-1 has several 2 mm long Bragg grating segments 40-2 evenly distributed along the axial direction with a spacing of 30 mm. The fiber ends are connected to the fiber demodulation unit 40-2-D via FC / PC fiber connector 40-1a. The sampling frequency is not less than 1 kHz. The data is converted into strain for each segment by the local MCU 40-2-M and output through CAN-FD or bus output interface 40-2-O.

[0062] like Figure 6 As shown, a MEMS accelerometer 60 is placed near each joint gear, with a sampling frequency of no less than 50kHz, focusing on monitoring the energy in the 5kHz to 20kHz frequency band. A MEMS microphone 70 is placed within a 60mm free span within the forearm of the chord 40 to pick up the fundamental frequency of the lateral vibration of the chord. The local MCU uses the string vibration formula... ,in The free span length of the tendon ligament. For tendon cord linear density, The fundamental frequency of transverse vibration, where Take 0.06 m, The linear density is pre-calibrated. The MCU compares the tension calculated by the FBG in real time. Tension inversely related to string vibration ,when Furthermore, if the duration exceeds three flexion-extension cycles, it serves as a health warning indicating localized fiber rupture in the output tendon chord.

[0063] like Figure 7 As shown, multiple actuator units 80 are arranged in a rectangular array inside the forearm housing 4. Each actuator unit 80 is equipped with a motor 80-1. The output shaft of the motor 80-1 is driven by a planetary reducer 80-2, and the planetary reducer 80-2 is driven by a winding reel 80-3 that is rotatably installed inside the forearm housing 4.

[0064] like Figure 8 As shown, the outer side of the main body is also covered with a detachable chemical splash shield 90, which is made of ETFE or FEP. It is connected to the M2 torque limiting locking part 92 by the alignment pin 91. The torque limit is no more than 2 Nm. It can be repeatedly installed and removed at least 1000 times. The chemical splash shield 90 is provided with multiple activated carbon filter ventilation ports 93.

[0065] Example 3: Enhanced Example of a Chemical Experiment Scenario

[0066] This embodiment has a structure that is basically the same as that of Embodiment 2, but four enhancement designs have been made for chemical experiment scenarios.

[0067] First, the tendon cord 40 is made of a composite braided material of PEEK and ultra-high molecular weight polyethylene to significantly improve its resistance to chemical reagents such as organic solvents, acids, and alkalis. The diameter of this composite braided tendon cord remains 0.4 mm, and its breaking load and working tension range are the same as in Example 2.

[0068] Second, the chemical splash guard 90 is made of PFA (perfluoroalkoxyethylene) material, which can withstand common organic solvents, strong acids and alkalis, and localized heat sources up to 80°C. The guard is connected to the forearm housing 4 via a positioning pin 91 and a torque-limiting locking element, with a torque limit not exceeding 2 Nm, and can be repeatedly installed and removed at least 1000 times.

[0069] Third, a PFA elastic cap is added to the outside of the fingertip six-dimensional force sensor 50. This elastic cap can effectively prevent chemical reagents from directly contacting the sensor electrodes, thereby protecting the long-term stability of the sensor. The position and function of the six-dimensional force sensor 50 itself are the same as in Embodiment 2.

[0070] Fourth, an activated carbon filter vent is added inside the forearm housing 4. This vent can actively expel chemical vapors that may be generated by the heat dissipation of the sensor or motor, preventing the accumulation of harmful gases. The activated carbon filter vent is located on the side of the forearm housing 4 and is connected to the heat dissipation channel of the actuator unit.

[0071] The other structures, working principles, and dual-modal health monitoring processes in this embodiment are the same as in Embodiment 2. Specifically, this includes: the size and manufacturing process of the palm 1, the layout of the 15 actuator units in the forearm actuator assembly, and... Figure 7 The topology shown, the module, pressure angle, tooth width, pitch circle radius, number of teeth, involute tooth profile, and SLM titanium alloy 3D printing manufacturing process, and non-circular rim are all described. Function expression The invention includes four enhancements: the arrangement and demodulation link of fiber Bragg grating fiber 40-1 and Bragg grating segment 40-2; the sampling parameters of MEMS accelerometer 60 and MEMS microphone 70; and the logic for detecting dual-mode consistency discrepancies. Through these four enhancements, the invention can operate safely and reliably in harsh environments such as automated chemical experiments.

[0072] The above specific embodiments are merely several optional embodiments of the present invention. Based on the technical solutions of the present invention and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A rope-driven high-fingertip force high-joint-stiffness dexterous hand, characterized in that, It includes a forearm housing (4), a five-finger multi-joint skeleton, several actuator units disposed within the forearm housing (4), and several tendon cords (40) connecting the actuator units to each finger joint (2); characterized in that: The five-finger multi-joint skeleton is provided with an integral molding mechanism between each two adjacent phalanges (2). The outer edge of the integral molding mechanism is a tooth profile, and it forms a pure rolling contact with the corresponding tooth profile on the adjacent phalanges (2) to form a joint. The integral molding mechanism has two concentric wheel sets embedded inside. The outer diameter wheel (13) of the concentric wheel set is used for the tendon rope (40) to be wound, and the inner diameter wheel (14) is used to connect the knuckle (2) through a connecting rod. The effective radius of the outer diameter wheel (13) is... With respect to the effective radius of the inner diameter wheel (14) The ratio constitutes the tension amplification factor And the tension amplification rate It is the joint angle Preset differentiable functions This causes the tension of the tendon rope (40) to be reduced. Mechanically magnified The force is then applied to the knuckle (2) to create a high fingertip force; The tendon cord (40) is a braided cord with at least one fiber Bragg grating embedded in it. The fiber Bragg grating is used to measure the strain distribution along the entire length of the tendon cord (40) in real time.

2. The rope-driven, high-fingertip-force, high-joint-rigidity dexterous hand according to claim 1, characterized in that, The tension amplification The value range is [1.5, 5].

3. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, The function The constant is a constant. .

4. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 3, characterized in that, The function ,in , The constant is preset so that the tension amplification rate increases monotonically as the joint flexion angle increases.

5. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, The integrated high-rigidity joint molding mechanism is manufactured by SLM titanium alloy or SLA photopolymerization 3D printing, and its tooth surface is honed to a certain surface roughness. And its modulus Pressure angle Tooth width Pitch circle radius Number of teeth The transmission ratio error is ≤ ±0.5%.

6. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, The tooth profile is any one of involute tooth profile, Bezier tooth profile, or non-circular pitch tooth profile. A MEMS accelerometer or acoustic emission sensor is placed near each joint to monitor and analyze energy changes in the 5-20 kHz frequency band during gear meshing. .

7. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, A MEMS microphone is provided at the span of the tendon cord (40) to pick up the fundamental frequency of the transverse vibration of the tendon cord (40). And through the string vibration formula Inversely, the tension of the tendon cord (40) is calculated. The chord tension is calculated using the string vibration method. The length of the free span of the tendon ligament. This represents the linear density of the tendon ligament.

8. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, The five-finger multi-joint skeleton has a total of 20 joints and 15 active degrees of freedom. The distal interphalangeal joints of the four fingers are driven joints and are empirically coupled to the corresponding proximal interphalangeal joints. A six-dimensional force / torque sensor is set at each fingertip. The tendon cord (40) has a diameter of 0.4 mm, a pretension of 16 N, and a working tension limit of 80 N; the maximum fingertip force for each finger is 24 N.

9. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 1, characterized in that, The forearm housing (4) is provided with a removable ETFE, FEP or PFA chemical splash shield (90) on its outer side. The shield (90) is connected to the dexterous hand body via a positioning pin (91) and a torque limiting locking member. The torque limiting locking member limits the torque of the dexterous hand body. ; The forearm housing (4) contains 15 actuator units, each of which includes a hollow cup brushless motor or servo motor, a planetary reducer and a tendon cable reel.

10. A rope-driven dexterous hand with high fingertip force and high joint stiffness according to claim 7, characterized in that, The fiber Bragg grating fiber is provided with multiple grating segments along the entire length of the tendon (40), each grating segment being 2 mm long and spaced 5-30 mm apart; when the tension is pushed back by the fiber Bragg grating The tension inversely inferred by the MEMS microphone through string vibration satisfy Furthermore, when the duration exceeds three flexion-extension cycles, a dual-modal consistent contradictory health alarm is output to indicate local fiber rupture in the tendon chord; the ends of the fiber Bragg gratings are connected to the FBG demodulation unit via an FC / PC connector, and then the strain of each grating segment is transmitted via a CAN-FD or EtherCAT bus. Tension in reverse propagation with fiber Bragg grating Output to the automatic control unit.

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