Dual-motor rope drive structure of humanoid robot dexterous hand and control method

Abstract

The dual-motor rope-driven structure comprises a palm seat, a plurality of steering engines, first joint connecting seats, a rope-driven disc mounting seat, second joint connecting seats and finger parts, the steering engines are mounted on the palm seat, each steering engine is connected with one first joint connecting seat, and the rope-driven disc mounting seat is connected with the corresponding second joint connecting seat. The first joint connecting seat is rotationally connected with a rope driving disc mounting seat, the rope driving disc mounting seat is connected with a second joint connecting seat, the second joint connecting seat is rotationally connected with the other rope driving disc mounting seat, and the other rope driving disc mounting seat is connected with a finger part; the steering engine is used for driving the two adjacent first joint connecting seats to move close to or away from each other, the rope driving disc mounting seats are used for being driven by externally-loaded motors to rotate, the externally-loaded motors comprise a motor A and a motor B, rope driving discs are arranged on the two sides of the rope driving disc mounting seats, and the motor A and the motor B are connected with the rope driving discs on one side through tendon ropes and independently drive the rope driving discs to rotate. The problem that a conventional humanoid robot dexterous hand is insufficient in control precision is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robot dexterous hand, in particular to a double-motor rope driving structure and control method of humanoid robot dexterous hand. BACKGROUND

[0002] The current market humanoid robot dexterous hand, its joint driving mode is mainly divided into gear driving and tendon driving two, and generally adopts the design of single motor driving a joint. This single motor driving mode has obvious defects in practical application: In the joint reversing process, it is easy to appear motion dead zone, which affects the continuity and accuracy of joint movement. For the rope driving mode, even if the fastening device is added to tighten the tendon, it is difficult to ensure that each tendon can be uniformly and stably fastened, which leads to the occurrence of tendon relaxation phenomenon, further reducing the control accuracy of the joint.

[0003] Therefore, a double-motor rope driving structure and control method of humanoid robot dexterous hand is needed to solve the problem of insufficient control accuracy of conventional humanoid robot dexterous hand. SUMMARY

[0004] The present application provides a double-motor rope driving structure and control method of humanoid robot dexterous hand to solve the problem of insufficient control accuracy of conventional humanoid robot dexterous hand.

[0005] To achieve the above purpose, the following technical solutions are adopted: A double-motor rope driving structure of humanoid robot dexterous hand, characterized in that: it comprises a palm seat, a plurality of rudders, a first joint connecting seat, a rope driving disc mounting seat, a second joint connecting seat and a finger part, a plurality of rudders are installed on the palm seat at intervals, each rudder is used for connecting a first joint connecting seat, a rope driving disc mounting seat is rotatably connected to the upper end of the first joint connecting seat, a second joint connecting seat is connected to the rope driving disc mounting seat, the second joint connecting seat is rotatably connected to another rope driving disc mounting seat, and the finger part is fixedly connected to the other rope driving disc mounting seat; the rudders are used for driving the adjacent two first joint connecting seats to move close to or away from each other, the rope driving disc mounting seat is used for being driven by an external load motor and rotating in a direction perpendicular to the moving surface of the corresponding first joint connecting seat, the external load motor comprises a motor A and a motor B, and the rope driving disc mounting seat is symmetrically provided with a rope driving disc on both sides, the motor A and the motor B are connected to the rope driving disc on one side through tendons and independently drive the rotation thereof.

[0006] To optimize the above technical solutions, the following specific measures are taken: Further, the side section of the rope driving disc mounting seat is in the shape of U, the rope driving disc is arranged on the outer side wall of the two ends of the U-shaped rope driving disc mounting seat, and the middle of the U-shaped rope driving disc mounting seat is provided for inserting and rotatingly connecting the first joint connecting seat or the second joint connecting seat.

[0007] Further, an inductive encoder is embedded at the rotating connection position of the rope driving disc mounting seat and the first joint connecting seat or the second joint connecting seat.

[0008] Further, a rope running groove is arranged on the lower rope driving disc mounting seat.

[0009] Further, the rope driving disc is in the shape of a disc, the end of the rope driving disc away from the rope driving disc mounting seat is arranged with a plurality of rope clamping blocks in the shape of a ring, a rope clamping groove is arranged between adjacent rope clamping blocks, a clamping groove is arranged on the side of the rope clamping block close to the center of the rope driving disc and communicated with the rope clamping groove, and a winding groove is arranged on the side wall of the rope driving disc and communicated with the rope clamping groove, the tendon rope is wound around the rope clamping block and connected in the rope clamping groove, the winding groove and the clamping groove.

[0010] Further, the output shafts of the motor A and the motor B are respectively connected with a rope driving disc, and the tendon ropes are respectively connected with the rope driving discs on the two sides of the rope driving disc mounting seat.

[0011] Further, the motor A and the motor B are respectively provided with an encoder.

[0012] Further, a control method is provided, characterized in that the method comprises the following steps: Step 1: defining the rotation angle, speed, output torque of the motor A, the rotation angle, speed, output torque of the motor B, the expected rotation angle, actual rotation angle of the rope driving disc mounting seat, common mode, difference mode. Step 2: calculating the common mode, difference mode, expected rotation angle, wherein, the transmission ratio is the ratio of the output torque of the motor A to the output torque of the motor B. Step 3: when working normally, the accurate angle control or the large output control is selected according to the requirement, when the accurate angle control is selected, the motor A and the motor B are controlled to rotate reversely, when the large output control is selected, the motor A and the motor B are controlled to rotate in the same direction, and the total output torque is the sum of the output torque of the motor A and the output torque of the motor B.

[0013] Further, the method further comprises the following steps: ​​​​​​​​​​​​​​​A device for acquiring acceleration signals is installed at the fingertip. Accelerometer and for acquiring contact force signals The tactile sensor, when or At that time, it was determined that an external impact had been detected, among which, The preset acceleration threshold value ranges from 1 to 10 m / s². The preset force threshold is set, with a value range of 10-100N; at this time, the formula is used... Obtain the current differential modulus Adjustments were made, including The relaxation coefficient is 0. <k<1。

[0014] Furthermore, it also includes the following steps: Rotation angle acquired by encoders of motors A and B and The desired rotation angle of the rope drive disc mounting base is calculated. The actual rotation angle is obtained by the inductive encoder on the rope drive reel mounting base. Calculate the deviation ,when hour, A preset fault threshold, ranging from 0.5 to 2°, is used to determine if a tendon or chordae is ruptured.

[0015] The beneficial effects of this invention are: This invention employs a dual-motor drive for a cable drive disc mounting base that serves as a joint. By increasing the differential modulus of the reverse-drive motor to tighten the tendon cable, the gaps similar to gear drives are effectively offset, dead zones during reversal are avoided, and precise angle control of the joint is achieved. The co-drive motor can achieve twice the output of a single motor, meeting the demands of large loads.

[0016] This invention designs a rope drive disc assembly that combines a "bowl-shaped" rope groove with a rope winding groove, ensuring the firm fixation of the tendon rope, avoiding tendon rope slackness, and further improving the stability and precision of joint movement.

[0017] This invention utilizes accelerometers and tactile sensors to detect external impacts, and achieves flexible control by rapidly reducing the differential modulus, thereby reducing the damage to the mechanical structure caused by external impacts and extending the service life of the dexterous hand.

[0018] This invention has a fault redundancy function. When the tendon ligament is broken, the controller parameters can be adaptively adjusted to still ensure normal angle control of the joint, thus improving the reliability of dexterity work.

[0019] The application realizes single-circle absolute value measurement by using a small inductive encoder, greatly reduces the interference between adjacent knuckles, and improves the accuracy of angle measurement; the encoder is arranged on the motor side, which reduces the cost while meeting the control requirement. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A schematic diagram of the overall structure of a double-motor rope drive structure of a dexterous hand of a humanoid robot according to the present application; Figure 2 A schematic diagram of the overall structure of a double-motor rope drive structure of a dexterous hand of a humanoid robot according to the present application; Figure 3 A schematic diagram of the overall structure of a double-motor rope drive structure of a dexterous hand of a humanoid robot according to the present application; Figure 4 A schematic diagram of the overall structure of a double-motor rope drive structure of a dexterous hand of a humanoid robot according to the present application.

[0021] The drawings show that the double-motor rope drive structure of the dexterous hand of the humanoid robot according to the present application comprises a palm base, a plurality of servo motors, a first joint connecting base, a rope drive disc mounting base, a second joint connecting base, and a finger part. DETAILED DESCRIPTION

[0022] The present application will now be further described in detail with reference to the accompanying drawings.

[0023] As shown in the drawings, the double-motor rope drive structure of the dexterous hand of the humanoid robot according to the present application comprises a palm base, a plurality of servo motors, a first joint connecting base, a rope drive disc mounting base, a second joint connecting base, and a finger part. Figure 1 The palm base is provided with a plurality of servo motors at intervals, each servo motor being used to connect a first joint connecting base, the upper end of the first joint connecting base being rotatably connected to a rope drive disc mounting base, the rope drive disc mounting base being connected to a second joint connecting base, the second joint connecting base being rotatably connected to another rope drive disc mounting base, and the other rope drive disc mounting base being fixedly connected to the finger part.

[0024] In the above specific embodiment, the side section of the rope drive disc mounting base is in the shape of a U, the rope drive disc 1 is arranged on the outer side wall of the two ends of the U-shaped rope drive disc mounting base, and the middle of the U-shaped rope drive disc mounting base can be inserted and rotatably connected by the first joint connecting base or the second joint connecting base.

[0025] As shown in the accompanying drawings, wherein the rope drive disc mounting seat and the first joint connecting seat or the second joint connecting seat are rotatably connected with a small inductive encoder. In this way, the absolute value of the joint single circle is measured by the small inductive encoder, and due to the inductive measurement principle, the electromagnetic interference between adjacent finger joints can be greatly reduced, and the accuracy of joint angle measurement is improved. Figure 3

[0026] In the present scheme, the small inductive encoder includes an inductive encoder rotor 9 and an inductive encoder stator 10, which are correspondingly installed on the first joint connecting seat or the second joint connecting seat, and the rope drive disc mounting seat. The gap between the inductive encoder rotor 9 and the inductive encoder stator 10 is uniform, and the gap value is 0.6mm, which reduces the influence of vibration on measurement.

[0027] In the present scheme, the anti-interference principle of the inductive encoder is as follows: The inductive encoder generates an alternating magnetic field through the transmitting coil, and the receiving coil outputs an induced signal according to the magnetic field change caused by the joint rotation, which is not easily affected by electromagnetic interference. Compared with the magnetic encoder, in the scenario of dense arrangement of multi-finger joints of the dexterous hand, the electromagnetic noise generated by the motors and wires of adjacent joints will not interfere with the induced signal of the inductive encoder, and the measurement error can be reduced by more than 30%, ensuring the accuracy of joint angle measurement.

[0028] In the present scheme, the rope drive disc mounting seat on the lower side is also provided with an up-and-down through rope groove 4. In the present scheme, the rope groove 4 can provide the tendon 7 of the previous rope drive disc mounting seat with a wiring channel, avoid mutual interference of the wiring of multiple rope drive disc mounting seats, and ensure the orderly operation of the overall rope drive system.

[0029] As shown in the accompanying drawings, in another specific embodiment based on the above, the rope drive disc 1 is disc-shaped, and the end of the rope drive disc 1 away from the rope drive disc mounting seat is annularly distributed with a plurality of rope clamping blocks, a rope clamping groove 3 is left between adjacent rope clamping blocks, and a clamping groove in communication with the rope clamping groove 3 is also provided on the side of the rope clamping block close to the axis of the rope drive disc 1. The side wall of the rope drive disc 1 is also provided with a ring of rope winding grooves 2 in communication with the rope clamping groove 3, and the tendon 7 is wound around the rope clamping block and connected in the rope clamping groove 3, the rope winding groove 2 and the clamping groove. Figure 2 In the present scheme, after the tendon 7 is knotted, it is wound for multiple turns or 0.5-1 turn in the rope clamping groove 3, the rope winding groove 2 and the clamping groove, and then the thread end 8 is clamped into the gap of the rope clamping groove 3, realizing firm fixation of the tendon 7. The rope drive discs 1 at both ends of each rope drive disc mounting seat are symmetrically arranged, and are respectively connected with the external load motor through two tendons 7 in different directions, forming a driving structure similar to "double synchronous belt", and realizing bidirectional rotation driving of the rope drive disc mounting seat.

[0030] ​​

[0031] In the above scheme, the rope groove 2 and the like are used to wind the tendon 7, so as to ensure that the tension of the tendon 7 can be stably converted into the rotation of the rope drive disc mounting seat.

[0032] In the above scheme, the rope drive disc 1 can be made of aluminum alloy material, and the thickness is 3-5 mm. The rope groove 2, the rope clamping groove 3 and the rope running groove 4 are integrally formed, so as to avoid the clamping stagnation or the wire interference of the tendon 7 in the movement process. The inner wall of the bowl-shaped rope drive disc 1 is smoothly transitioned by a circular arc, and the edge of the rope clamping groove 3 is rounded with a radius of 0.5-1 mm, so as to prevent the tendon 7 from being abraded. The hole diameter of the rope running groove 4 is larger than the diameter of the tendon 7 by 0.2-0.5 mm, so as to ensure that the tendon 7 can smoothly pass through and not excessively shake. The tendon 7 is made of high-strength aramid fiber material, and the diameter is 0.5-1.5 mm. The length deviation of the two tendons 7 is controlled to be within ±0.5 mm, so as to ensure the driving synchronization. The wire end 8 needs to ensure that the diameter is obviously larger than the width of the rope clamping groove 3, so that the tendon 7 can be fixed at both ends of the rope drive disc 1. As shown in the accompanying drawings Figure 4 In another specific embodiment based on the above, the output shafts of the motor A5 and the motor B6 are respectively connected with a rope drive disc 1, and are respectively connected with the rope drive discs 1 on both sides of the rope drive disc mounting seat through the tendons 7. In this scheme, the rope drive disc 1 of the motor output shaft is matched with the rope drive discs 1 on both sides of the rope drive disc mounting seat. The rope drive disc 1 and the output shaft are fixedly connected through a key, and the coaxiality error is less than or equal to 0.05 mm, so as to ensure stable power transmission. In another specific embodiment based on the above, the motor A5 and the motor B6 are both provided with an encoder for collecting the rotation angle and speed information of the motor in real time. The encoder is connected with the output shaft of the motor through an elastic coupling, so as to further reduce the vibration interference and improve the angle and speed collection accuracy. The collection frequency can reach 10 kHz, so as to meet the real-time control requirement.

[0033] A control method applied to the double-motor rope drive structure of the anthropomorphic robot dexterous hand described above, including the following steps: Step 1: defining the rotation angle , the speed , the output torque of the motor A5, the rotation angle , the speed , the output torque of the motor B6, the expected rotation angle , the actual rotation angle of the rope drive disc mounting seat, the common mode representing the actual motion state of the motor, and the differential mode representing the tightness of the tendon, The greater the differential mode is, the tighter the tendon is, the higher the control bandwidth of the system is, and the better the control accuracy is; on the contrary, The smaller the differential mode is, the more relaxed the tendon is; Step 2: Calculate the common mode , the differential mode , the desired rotation angle , wherein is the transmission ratio, and the movement angle of the rope drive disc mounting seat can be controlled by controlling the common mode ; Step 3: During normal operation, select precise angle control or large output control according to requirements. When precise angle control is selected, control the motor A5 and the motor B6 to rotate in opposite directions to adjust the tracking and increase ; when large output control is selected, control the motor A5 and the motor B6 to rotate in the same direction, and the total output torque .

[0034] In the control method of the application, the force transmission principle of the double-motor rope drive is as follows: When the double-motor drives the joint to rotate through the tendon rope, the output torque , of the double-motor is converted into the tension of the tendon rope 7 , , is the radius of the motor-side rope drive disc 1. The driving torque received by the rope drive disc mounting seat , is the radius of the rope drive disc 1 on the side of the rope drive disc mounting seat. When the two motors rotate in the same direction, and are superimposed in the same direction, and the driving torque is maximum; when the two motors rotate in opposite directions, and are opposite to form a tension difference, so that the tendon rope 7 is tightened and the gap is offset.

[0035] Further, in step 3 above, when precise angle control is selected, the angle control error needs to satisfy , wherein is a preset angle accuracy threshold, and the value range is 0.1-0.5°, and the value range of the differential mode is 0.5-5°, which is determined according to the system bandwidth requirement. The higher the bandwidth requirement is, the larger the value is.

[0036] Specifically, when precise angle control is selected: when precise angle driving is required, control the two motors to rotate in opposite directions, i.e. the motor A5 rotates forward and the motor B6 rotates reversely, or vice versa. At this time, the differential mode increases, the tendon rope 7 is tightened, and the gap similar to the gear drive can be offset, and the angles of the motor A5 and the motor B6 are adjusted through closed-loop control, so that the common mode tracks the desired rotation angle of the joint , i.e. ​Thus, the precise angle control of the rope drive disc mounting seat is realized, and the angle control error meets .

[0037] High-power control: when a large one-way output is needed, control the two motors to rotate in the same direction. At this time, the output torque of motor A5 and motor B6 is superimposed, that is, the total output torque , which can realize the output of twice the output of a single motor, meeting the demand of large load working condition.

[0038] Further, the transmission ratio in step 3 above is determined by the radius of the rope drive disc and the winding number of the tendon rope 7 , and the specific calculation formula is , wherein is the displacement of the tendon rope 7 corresponding to the angle of the rope drive disc mounting seat.

[0039] Further comprising the following steps: A sensor for detecting impact is arranged at the end of the finger, and when the sensor detects impact, the flexible control is realized, that is: An acceleration sensor for collecting acceleration signals and a tactile sensor for collecting contact force signals are arranged at the end of the finger, and when or , it is determined that external impact is detected, wherein is a preset acceleration threshold, and the value range is 1-10 m / s², is a preset force threshold, and the value range is 10-100 N; at this time, the current differential modulus is obtained by the formula for adjustment, wherein is a relaxation coefficient, 0<k<1, and the impact intensity and satisfy a negative correlation, that is , when , .

[0040] Specifically, when the sensor detects that the end hits the obstacle, that is, the acceleration signal exceeds the preset acceleration threshold or the contact force signal exceeds the preset force threshold , the control system quickly reduces the differential modulus , that is, the motor A5 and the motor B6 are controlled to rotate in the direction of reducing the angle difference, so that the tendon rope is relaxed, flexible control is realized, and the damage of external impact to the mechanical structure is reduced. The differential modulus adjustment formula when the impact occurs is: , The value of the impact strength is self-adaptively adjusted according to the impact strength, and the greater the impact strength is, The smaller.

[0041] Further comprising the following steps: When the tendon 7 is detected to be broken, the controller parameters are self-adaptively adjusted to enter a redundancy mode to ensure normal movement of the tendon-driven disk seat as a joint, that is: The rotation angle collected by the encoders of the motor A5 and the motor B6 And The expected rotation angle of the tendon-driven disk seat is calculated The actual rotation angle is collected by the inductive encoder of the tendon-driven disk seat The deviation is calculated When , The preset fault threshold is 0.5-2°, and the tendon is determined to be broken; when the controller parameters are adjusted, the controller parameter self-adaptive adjustment formula is: the angle loop proportional coefficient , the integral coefficient , wherein the parameter adjustment coefficient is determined according to the angle deviation, When , .

[0042] Specifically, when it is detected that a tendon 7 is broken, whether the deviation between the rotation angle information collected by the motor encoder and the rotation angle information collected by the tendon-driven disk seat encoder exceeds the preset fault threshold is judged to determine whether the system enters a redundancy working mode. At this time, although the tendon 7 is broken to cause the output to decrease, the total output becomes the output of a single motor , the accuracy is reduced, but the tendon-driven disk seat can still be normally controlled in angle by self-adaptively adjusting the controller parameters, such as increasing the angle loop proportional coefficient , the integral coefficient .

[0043] The adaptive adjustment principle of the redundancy control in the control method of the application is as follows: When the tendon 7 is broken, the system judges the fault degree through the angle deviation The parameter adjustment coefficient increases with the increase of , so that the angle loop gain of the controller is correspondingly improved to compensate for the decrease of the driving force caused by the breaking of the tendon 7. At the same time, the system real-time monitors the movement speed and acceleration of the tendon-driven disk seat, and when the speed fluctuation exceeds the preset range (±5%), the integral coefficient is further fine-tuned to avoid overshoot or oscillation of the tendon-driven disk seat movement and ensure the movement stability in the redundancy mode.

[0044] One specific embodiment of the present invention is as follows: The rope groove 2 is 1mm wide and 2mm deep. The "bowl-shaped" rope groove 3 is 20mm in diameter, with an opening diameter of 12mm, a top that tapers inward by 4mm, and 12 evenly spaced gaps of 0.5mm wide around it. The drive motor is a DC servo motor or a stepper motor with a rated torque of 0.1-2 N·m. Specifically, the drive motor is a DC servo motor with a rated torque of 0.5 N·m. The motor-side encoder resolution is 500-2000 lines, specifically, the encoder resolution is 1000 lines. The inductive encoder resolution is 2048-8192 lines, with a measurement accuracy of ±0.05-±0.2°. Specifically, the inductive encoder on the rope drive reel mounting side has a resolution of 4096 lines, a single-turn measurement range of 0-360°, and a measurement accuracy of ±0.1°. Preset angle accuracy threshold Preset acceleration threshold Preset force threshold Preset fault threshold relaxation coefficient The value range is 0.3-0.8, and the parameter adjustment coefficient is... The value range is 0.2-0.5.

[0045] The control process is as follows: 1. During normal and precise angle control, set the desired rotation angle for the rope drive disc mounting base. According to the transmission ratio Calculate the expected value of the common modulus. Control motors A5 and B6 to rotate in opposite directions. By adjusting the rotation angles of motors A5 and B6, the common modulus is adjusted. track At the same time, make the differential modulus The actual rotation angle of the rope drive disc mounting base is set according to the system bandwidth requirements. It stabilizes at around 30°, with a rotation angle error of less than 0.2°.

[0046] 2. When high output is required, control motors A5 and B6 to rotate in the same direction. The output torque of motors A5 and B6 both reach 0.5 N·m, and the total output torque reaches 1 N·m, which meets the requirements of high load drive.

[0047] 3. When the dexterous hand's end strikes an obstacle, the acceleration sensor detects it. At that time, the control system quickly changed the differential modulus. Adjusted from 2° to Based on impact strength , the tendon 7 is relaxed, and flexibility impact resistance is realized.

[0048] 4. When one tendon 7 is detected to be broken, the rotation angle information collected by the motor encoder deviates from the angle information collected by the rope drive disc mounting seat encoder , the system enters a redundancy mode, and the angle loop proportional coefficient is adjusted from 2 to , the integral coefficient is adjusted from 0.5 to , at this time, the rope drive disc mounting seat can still move normally, and the position error is controlled within 0.5°.

[0049] Another specific embodiment of the application is as follows: For the scenario of multiple fingers and multiple joints of a dexterous hand working cooperatively, the double-motor rope drive structure and control method of the application are used, taking the cooperation of the thumb with three joints and the index finger with three joints to grasp an object as an example: 1. Structural parameters: the parameters of the rope drive disc 1 of each joint of the thumb and the index finger are unified, the width of the rope groove 2 is 1mm, the depth is 2mm, the diameter of the “bowl-shaped” rope clamping groove 3 is 20mm, the opening diameter is 12mm, the top is inwardly retracted by 4mm, and the gap number is 12; the driving motor is a direct current servo motor with a rated torque of 0.3N·m, the motor side encoder has a resolution of 1000 lines, and the joint side inductive encoder has a resolution of 4096 lines.

[0050] 2. Control parameters: the preset angle accuracy threshold , the acceleration threshold , the force threshold , and the fault threshold ; the transmission ratio of each joint is set according to the size difference of the joints, the proximal joint of the thumb , and the middle joint of the index finger .

[0051] 3. Cooperative control process: In the grasping initialization stage, the control system plans the expected rotation angle of each joint according to the size of the object , synchronously moves each joint to the pre-grasping position through common mode control, at this time the differential mode , and the angle accuracy of each joint is ensured; In the contact object stage, the tactile sensor detects the contact force , which does not reach the threshold, the differential mode is maintained unchanged, and the joint angle is fine-tuned through the common mode to stabilize the grasping force at 25-35N; In the accidental impact stage, if the object accidentally shakes during the grasping process, causing the acceleration of the thumb tip to be , the system quickly calculates the impact strength , and determines the relaxation coefficient The differential modulus of the thumb joints was adjusted from 1.5° to 1.2°, while keeping the index finger joint parameters unchanged to prevent objects from falling off. During the troubleshooting phase, if a tendon ligament ruptures at the distal phalanx of the index finger, and an angular deviation is detected... Calculate the parameter adjustment coefficient Angle ring at the joint Adjusted from 1.8 to 2.34 The value was adjusted from 0.4 to 0.52. At this point, the angle error of the distal phalanx of the index finger is controlled within 0.4°, which does not affect the overall grasping action.

[0052] The adaptability of the structure and control method of this invention was verified under harsh environments such as dust and vibration: 1. Structural protection: A dust cover is added to the outside of the joint-side rope drive disc 1. If a PTFE dust cover is used, a gap of 0.5-1mm is reserved between the dust cover and the rope drive disc 1 to avoid affecting the joint rotation; the motor-side drive mechanism adopts an IP65 protection level motor housing to prevent dust from entering the motor.

[0053] 2. Control Optimization: For vibration environments, a low-pass filter is added to the angle loop control, with the filter frequency set to 50Hz to reduce the interference of vibration on the motor angle detection; at the same time, the reference value of the differential modulus is adjusted from 1-2° in the normal environment to 2-3° to enhance the vibration resistance of the tendon rope 7.

[0054] 3. Verification results: In an environment with a vibration frequency of 10-50Hz and an amplitude of 0.1-0.5mm, the angle error of each joint of the dexterous hand can still be controlled within 0.4°; after working continuously for 200 hours in an environment with a dust concentration of 50mg / m³, the wear of tendon rope 7 is ≤0.05mm, the motor and encoder work normally, and no faults occur.

[0055] This invention overcomes the shortcomings of single-motor driven joints in humanoid robot dexterous hands, such as dead zones, insufficient force, lack of redundancy, poor flexible control, and inaccurate position measurement. It achieves precise joint position control, high force output, fault redundancy, flexible impact resistance, and high-precision position measurement, and is suitable for scenarios with high requirements for dexterous hand joint motion accuracy, force output, and flexible control.

[0056] The control method of this invention achieves joint position control and tension adjustment of tendon 7 by defining common modulus and differential modulus respectively; during normal operation, it can switch between precise position control and high output control; when an impact is detected, it reduces the differential modulus to achieve flexible control; when tendon 7 breaks, it adaptively adjusts the controller parameters to ensure redundant operation.

[0057] It should be noted that the terms such as "upper", "lower", "left", "right", "front", "back" and the like cited in the invention are only for the convenience of clear description, and are not used to limit the scope of the implementation of the invention. The change or adjustment of the relative relationship is also considered as the implementation of the invention without substantial change of the technical content.

[0058] The above is only the preferred embodiment of the present application, and the protection scope of the present application is not limited to the above-mentioned embodiments. Any technical solution falling within the concept of the present application is within the protection scope of the present application. It should be noted that for ordinary skilled persons in the art, it can be understood that various changes, modifications, replacements, refinements and modifications can be made to these embodiments without departing from the principles and spirits of the present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A dual-motor rope-driven structure for a humanoid robot's dexterous hand, characterized in that: The device includes a palm base, several servo motors, a first joint connector, a rope drive disc mounting base, a second joint connector, and a finger. Several servo motors are installed at intervals on the palm base. Each servo motor is used to connect to a first joint connector. A rope drive disc mounting base is rotatably connected to the upper end of the first joint connector. A second joint connector is connected to the rope drive disc mounting base. The second joint connector is rotatably connected to another rope drive disc mounting base. The finger is fixedly connected to the other rope drive disc mounting base. The servo motors are used to drive two adjacent first joint connectors to move closer or further apart. The rope drive disc mounting base is used to be driven by an external motor and rotate in a direction perpendicular to the moving surface of the corresponding first joint connector. The external motor includes motor A and motor B. Rope drive discs (1) are symmetrically arranged on both sides of the rope drive disc mounting base. Motor A (5) and motor B (6) are respectively connected to the rope drive disc (1) on one side through tendon ropes (7) and drive it to rotate independently.

2. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 1, characterized in that: The side section of the rope drive disc mounting base is U-shaped. The rope drive disc (1) is located on the outer side walls at both ends of the U-shaped rope drive disc mounting base. The middle of the U-shaped rope drive disc mounting base can be used to insert and rotate the first joint connecting seat or the second joint connecting seat.

3. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 2, characterized in that: An inductive encoder is embedded at the rotatable connection between the rope drive disc mounting base and the first joint connecting base or the second joint connecting base.

4. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 2, characterized in that: The rope drive disc mounting base located below is also provided with a rope running groove (4) that runs vertically through the top and bottom.

5. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 1, characterized in that: The rope drive disc (1) is disc-shaped. Several rope clamping blocks are arranged in a ring at the end of the rope drive disc (1) away from the rope drive disc mounting base. There are rope clamping grooves (3) between adjacent rope clamping blocks. The side of the rope clamping block near the axis of the rope drive disc (1) is also provided with a groove that communicates with the rope clamping groove (3). The side wall of the rope drive disc (1) is also provided with a winding groove (2) that communicates with the rope clamping groove (3). The tendon rope (7) is wrapped around the rope clamping block and connected in the rope clamping groove (3), the winding groove (2) and the groove.

6. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 1, characterized in that: The output shafts of motor A (5) and motor B (6) are respectively connected to a rope drive disc (1), and are respectively connected to the rope drive discs (1) on both sides of the rope drive disc mounting base via tendon ropes (7).

7. The dual-motor rope-driven structure for a humanoid robot dexterous hand according to claim 1, characterized in that: Both motor A (5) and motor B (6) are equipped with encoders.

8. A control method applied to the dual-motor rope-driven structure of the humanoid robot dexterous hand according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Define the rotation angle of motor A (5) ,speed Output torque The rotation angle of motor B (6) ,speed Output torque Rope drive disc mounting bracket expected rotation angle Actual turning angle common modulus Difference modulus ; Step 2: Calculate the common modulus Difference modulus Expected corner ,in, The transmission ratio; Step 3: During normal operation, select either precise angle control or high-output control as needed. In precise angle control, control motor A (5) and motor B (6) to rotate in opposite directions; in high-output control, control motor A (5) and motor B (6) to rotate in the same direction, with a total output torque of [missing value]. .

9. The control method according to claim 8, characterized in that, It also includes the following steps: A device for collecting acceleration signals is installed at the fingertip. Accelerometer and for acquiring contact force signals The tactile sensor, when or At that time, it was determined that an external impact had been detected, among which, The preset acceleration threshold value ranges from 1 to 10 m / s². The preset force threshold is set, with a value range of 10-100N; at this time, the formula is used... Get the current differential modulus Adjustments were made, including The relaxation coefficient is 0. <k<1。 10. The control method according to claim 8, characterized in that, It also includes the following steps: The rotation angle is collected by the encoders of motor A (5) and motor B (6). and The desired rotation angle of the rope drive disc mounting base is calculated. The actual rotation angle is obtained by the inductive encoder on the rope drive reel mounting base. Calculate the deviation ,when hour, A preset fault threshold, ranging from 0.5 to 2°, is used to determine if a tendon or chordae is ruptured.

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