53 results about "Underactuated robots" patented technology

The invention discloses a self-adaptive underactuated robot clamping claw which comprises a clamping claw shell, a drive module and finger modules. The clamping claw shell comprises a front clamping claw shell body, a rear clamping claw shell body and a fixing flange, wherein the front clamping claw shell body and the rear clamping claw shell body are connected and are further in bolt connection with the fixing flange. The drive module is arranged in the clamping claw shell and comprises a drive motor, a power transmission device and drive rods. The drive motor is used for driving the drive rods to make synchronous linear motion and transmitting torque through the power transmission device. The finger modules comprise the first finger module and the second finger module which are each provided with a first finger section and a second finger section. Each first finger section and the corresponding second finger section are hinged to the corresponding drive rod through a self-adaptive connecting rod system and a parallel connecting rod system, and area driven to move through the drive rod. The self-adaptive underactuated robot clamping claw can grab objects in different shapes in different manners, is suitable for requirements of different occasions and high in clamping range and clamping force, and can grab the objects more conveniently.

The invention relates to a connecting-rod-type underactuated robot finger mechanism with all-rotational joints and aims to solve the problem that the conventional finger mechanism is small in grasping force and not easy to manufacture and maintain. The finger mechanism is characterized in that the upper part of a first connecting rod is hinged to a second connecting rod; the lower part of the first connecting rod is hinged to a third connecting rod driven by a motor and a speed reducer; the tail end of the third connecting rod is hinged to a fourth connecting rod; a spring is mounted between the third connecting rod and the fourth connecting rod; the tail end of the fourth connecting rod is hinged to a fifth connecting rod and a seventh connecting rod respectively; a spring is mounted between the fifth connecting rod and the seventh connecting rod; a sixth connecting rod which takes the shape of an non-isosceles triangle I with a big obtuse angle is hinged between the tail end of the fifth connecting rod and the tail end of the second connecting rod; the vertex angle of the non-isosceles triangle I is hinged to the tail end of the second connecting rod; the short-edge base angle of the non-isosceles triangle I is hinged to the tail end of the fifth connecting rod; the long-edge base angle of the non-isosceles triangle I is hinged to an eighth connecting rod which takes the shape of an non-isosceles triangle II with a small obtuse angle; the vertex angle of the non-isosceles triangle II is hinged to the long-edge base angle of the non-isosceles triangle I; the short-edge base angle of the non-isosceles triangle II is hinged to the tail end of the seventh connecting rod. The finger mechanism has the advantages that the grasping force is large; the adaptability is good; the drive and the control are simple; the manufacture and the maintenance are easy.

The invention discloses a three-rack slider coupling adaptive underactuated robot finger device, and belongs to the technical field of anthropomorphic robot hands. The device comprises a base, a near joint shaft, a first finger segment, a far joint shaft, a second finger segment, a motor, a three-gear and rack transmission mechanism and a spring. The device achieve the transmission effect combining coupling rotation and underactuated rotation, can couple anthropomorphic grasp, and has the underactuated adaptive function. The whole finger has the advantages of concise structure and low manufacturing and processing cost; and the coupling rotation and the underactuated rotation are organically fused, natural decoupling is realized by utilizing a block moving contact mode, and the power of the motor is not consumed during the decoupling. The device has the advantages of compact structure, stable and accurate transmission, low manufacturing and maintaining cost and similar appearance to a human finger, can be used as one finger or a part of the finger of a robot hand, also can be combined with a plurality of the fingers into the robot hand so as to achieve the good effect of high degree of freedom of joints and high adaptivity of the anthropomorphic robot hand.

Belonging to the technical field of anthropomorphic robots, an underactuated robot finger device with tendons and gears comprises a base seat, a motor, a reducer, a first gear, a second gear, a near joint shaft, a middle finger section, a far joint shaft and a terminal finger section. The device also comprises a driving rope pulley, a transitional rope pulley, a transitional gear, a transitional shaft, a first tendon, a second tendon, a driven gear and a spring part. The device utilizes the gear and tendon transmission mechanism, the movably socketed middle finger section and the decoupling function of the spring part to comprehensively realize the special effect that the double-joint underactuated fingers are bent to grasp an object. Similar to a human finger, the device has the advantages of simple and reliable structure, low cost, convenient assembly and maintenance, small volume and light weight. The device is particularly used as the thumb or one part of other fingers of an anthropomorphic robot hand, so that the anthropomorphic robot hand can use less actuators to drive more rotating joints, and can be self-adapted to the shape and size of the grasped object.

The invention relates to a wrist device for a three degree of freedom (TDOF) underactuated robot. The device comprises a static platform, a movable platform, three branches and two drive power sources, wherein the static platform is hinged with the movable platform through the three branches, and two of the three branches are connected with the two drive power sources respectively; and under driving of the two drive power sources, the movable platform performs three degree of freedom motion through transmission of the three branches.

The invention discloses a magnetorheological fluid auxiliary flexible palm side self-adaption underactuated robot hand device, and belongs to the technical field of robots. The device comprises a flexible part, a tendon rope, fingers, a channel, coils, magnetorheological fluid, a driver and a base. The flexible part is of a cloth or net or film thin-wall structure, and the magnetorheological fluid is sealed inside the flexible part; the channel and the coils are arranged on the flexible part; and one end of the tendon rope is fixedly connected with an output shaft of the driver, and the other end of the tendon rope penetrates the channel and is fixedly connected with the tail end of the channel. According to the device, the tendon rope is utilized for pulling the channel, and the flexible part closes up a sealing opening, and the self-adaption grabbing function for objects in different shapes and with different sizes is achieved; elasticity of the fingers is utilized, the flexible part is kept in the optimum grabbing posture, and the flexible part can be reset; the characteristic that the magnetorheological fluid is solidified in a magnetic field is adopted, the grabbing form is fixed in an auxiliary manner, and reliable grasping is achieved; and according to the device, a few drivers are used for driving the multiple fingers, and the device is simple in structure and low in manufacturing and maintenance cost.

The invention discloses a pneumatic type underactuated robot finger device belonging to the technical field of humanoid robot hands. The pneumatic type underactuated robot finger device comprises a first finger section, a second finger section and an underactuated joint. The underactuated joint comprises an active sliding block, a joint shaft and two pneumatic flexible pieces; the active sliding block is embedded in the first finger section; the joint shaft is sleeved in the first finger section and the second finger section is sleeved and fixed on the joint shaft; the first pneumatic flexible piece is arranged between the first finger section and the active sliding block; the second pneumatic flexible piece is arranged between the first finger section and the second finger section; and the first pneumatic flexible piece and the second pneumatic flexible piece are communicated through a first finger section hole. The finger device adopts gas in a deformable closed space as a transmitting media, is combined with the pneumatic flexible pieces capable of axially stretching and bending, comprehensively realizes the inactive underactuated bending effect of fingers when grapping objects, has the function of automatically adapting to the size of the shape of the gripped objects as well as low manufacturing and maintenance cost, is similar to the fingers of human fingers and can be connected in series to form multi-joint fingers with high shape, self adaptability and high under actuation.

The differential bevel gear and rack type compound underactuated robot finger device belongs to the technical field of humanoid robot hand, including base, motor, reducer, proximal joint shaft, middle finger segment, distal joint shaft, end finger segment, rack and Spring parts. The device of the present invention adopts a single motor, multi-axis and multi-channel transmission mechanisms with different transmission ratios and spring parts to comprehensively realize the compound under-actuated grasping effect: the fingers are first coupled and rotated to grasp the object and then adaptively grasp the object; the grasping process Anthropomorphic, dexterous, stable grasping objects, can automatically adapt to grasping objects of different sizes and shapes, low requirements on the control system, easy to operate; at the same time, the structure is simple and compact, the energy loss is small, the transmission efficiency is high, the cost is low, and the assembly and maintenance are easy. Convenient, and the shape is similar to human fingers, suitable for humanoid robot hands.

The invention proposes a design and deployment scheme for a hyper-articulated manipulator for assembly operations inside an aircraft wing box. The manipulator comprises nested C-channel structures connected by 1 degree of freedom rotary joints. The wing box has a large span, but is only accessible through multiple small portholes along its length. The manipulator is compact enough to enter the wing-box through the portholes, yet capable of subsequent reconfiguration so as to access multiple assembly points inside the wing-box. Traditional electromechanical actuators powering the rotary joints are unsuitable for this purpose, because of limited space and large payload requirements. The manipulator is an underactuated system which uses a single actuator at the base for the deployment of the C-channel serial linkage structure. The deployment scheme modulates gravitational torques in the system dynamics to rapidly deploy the system to a desired final configuration starting from any initial configuration.

Belonging to the technical field of anthropomorphic robots, a multi-joint super underactuated robot finger device with racks comprises a base seat, a motor, a reducer, a first gear, a second gear, a near joint shaft, at least two middle finger sections, at least one middle joint shaft, a far joint shaft and a terminal finger section. The device also comprises at least two driving gears, at least two racks, at least two driven gears and at least two spring parts, and both ends of each spring part are respectively connected with adjacent finger sections. The device utilizes multiple pairs of gear and rack mechanisms, multiple movably socketed middle finger sections and the decoupling function of multiple spring parts to comprehensively realize the special effect that the multi-joint super underactuated fingers are bent to grasp an object; the structure is simple and reliable, the cost is low, and the fingers are similar to the fingers of a human hand; the device can be used as the fingers of a robot in order to realize that a robot hand can apply less actuators to drive more multi-joint degrees of freedom, and moreover, the device can be self-adapted to the shape of the grasped object.

Belonging to the technical field of anthropomorphic robots, a multi-joint super underactuated robot finger device with gears and belt wheels comprises a base seat, a motor, a near joint shaft, at least two middle finger sections, at least one middle joint shaft, a far joint shaft and a terminal finger section. The device also comprises a driven gear, at least two driving gears, near transitional gears, driving wheels, transmission parts, driven wheels, far transitional gears, spring parts, near transitional shafts and far transitional shafts. The device utilizes the designed gear and belt wheel transmission mechanism, multiple movably socketed middle finger sections and the decoupling function of multiple spring parts to comprehensively realize the special effect of that the multi-joint super underactuated fingers are bent to grasp an object; similar to the human fingers, the device can be used on a robot hand with the long middle finger sections of fingers and particularly used as the index finger, middle finger, ring finger and little finger of the anthropomorphic robot hand, so that the anthropomorphic robot hand can use less actuators to drive more rotating joints; when the middle finger sections are hindered while touching an object, the terminal finger sections can continue to move and grasp the object, and the device can be self-adapted to the shape and size of the grasped object; the device has the advantages of simple structure, low cost, convenient assembly and maintenance, reliable performance and long service life.

A finger device for an underactuated robot adapting along with shapes automatically belongs to the technical field of robot hands imitating a person hand. The finger device comprises a first finger section, a second finger section and an underactuated joint, wherein the underactuated joint comprises an air sac, a joint shaft, a pneumatic flexible part and a reed part. The finger device adopts the air sac to receive the air in a transform piece and a transformable closed space and turns the air into transmission medium, and when fingers are used for grabbing the objects, the passive underactuated bent effect for object pressure of any direction is comprehensively realized through the combination of device and the pneumatic flexible part capable of stretching and bending axially; large angle rotation of a second finger section can be realized by using very small deformation along with the shape of the air sac; the device does not limit the pressure direction of the object on the air sac, and the rotation of the second finger section can be realized by any pressure on the air sac; when grabbing the object, the device can adapt to the shape and size of the grabbed object automatically, the device has a simple structure, small volume and light weight, is low in manufacturing and maintenance costs, and is similar to fingers of the person hand; and the device can be connected in series so as to form highly-underactuated multi-joint fingers realizing strong self-adaption to shapes.

Belonging to the technical field of anthropomorphic robots, an underactuated robot finger device with crossed tendons comprises a base seat, a motor, a reducer, a first gear, a second gear, a near joint shaft, a middle finger section, a far joint shaft and a terminal finger section. The device also comprises a driving gear, a transitional gear, a driving rope pulley, a transitional shaft, a first tendon, a second tendon, a driven rope pulley and a spring part. The device utilizes the gear and tendon transmission mechanism, the movably socketed middle finger section and the decoupling function of the spring part to comprehensively realize the special effect that the double-joint underactuated fingers are bent to grasp an object. Similar to a human finger, the device has the advantages of simple and reliable structure, low cost, convenient assembly and maintenance, small volume and light weight. The device is particularly used as the thumb or one part of other fingers of an anthropomorphic robot hand, so that the anthropomorphic robot hand can use less actuators to drive more rotating joints, and can be self-adapted to the shape and size of the grasped object.

The invention discloses a flexible part crank block type parallel coupling underactuated robot finger device, and belongs to the technical field of anthropomorphic robot hands. The device comprises a base, a near joint shaft, a first finger segment, a far joint shaft, a second finger segment, a connecting rod, a drive plate, a motor, a flexible part and a spring. The device can achieve the transmission effect combining coupling rotation and underactuated rotation, can realize anthropomorphic grasp through coupling, and also has the underactuated adaptive function. The whole finger has the advantages of concise structure, low manufacturing and processing cost, natural decoupling by utilizing block moving contact mode, no need of power consumption of the motor and high energy utilization rate. A crank block mechanism of the second finger segment can realize large-angle rotation of the second finger segment by moving very short distance of an active block. The device is similar to a human finger in appearance, can be used as one finger or a part of the finger of a robot hand, also can be combined with a plurality of the fingers into the robot hand so as to achieve the good effect of high degree of freedom of joints and high adaptivity of the anthropomorphic robot hand.

The invention discloses a location control method of a 2R underactuated planar mechanical arm based on subdivision control. The location control method of the 2R underactuated planar mechanical arm based on subdivision control comprises the following steps: establishing an underactuated planar mechanical arm mechanics module with a driving first joint and a driven second joint, and considering Coulomb friction force and viscous friction force of joints in the module. To an underactuated robot, the friction of the driving joint can be directly compensated by a motor, but the driven joint can not be compensated, and the friction force of the driven joint is utilized. By adopting a time scale method and a proportion integration differentiation (PID) control method, the location control method of the 2R underactuated planar mechanical arm based on subdivision periodically starts joint space and location control to the 2R underactuated planar mechanical arm, and further achieves positioning control to the tail end of the robot. A research objective of the location control method is an underactuation system which includes entirely free joints, and so that the location control method of the 2R underactuated planar mechanical arm based on subdivision control has the advantages of being simplified in a mechanical device and pervasive in the control objective. The location control method of the 2R underactuated planar mechanical arm based on subdivision control utilizes a simple and feasible control method to realize the location control of the 2R underactuated planar mechanical arm, avoids to adopt complex and profound nonlinear control methods, and achieves the purposes of being distinct in train of thought, simple to programming and easy to achieve.

Belonging to the technical field of anthropomorphic robots, a tri-joint underactuated robot finger device with crossed tendons comprises a base seat, a motor, a near joint shaft, a first middle finger section, a second middle finger section, a middle joint shaft, a far joint shaft and a terminal finger section. The device utilizes the designed crossed tendon and gear transmission mechanism, two movably socketed middle finger sections and the decoupling function of two spring parts to comprehensively realize the special effect of that the tri-joint underactuated fingers are bent to grasp an object. Similar to a human finger, the device can be used on a robot hand with the long middle finger sections of fingers and particularly used as the index finger, middle finger, ring finger and little finger of the anthropomorphic robot hand, so that anthropomorphic robot hand can use less actuators to drive more rotating joints. When the middle finger sections are hindered while touching an object, the terminal finger sections can continue to move and grasp the object, and the device can be self-adapted to the shape and size of the grasped object. The device has the advantages of simple structure, low cost, convenient assembly and maintenance, reliable performance and long service life.

The invention relates to a finger device of a unilateral-coupling and self-adaption composite type underactuated robot, belonging to the technical field of humanoid robot hands. The finger device comprises a base, a motor, a speed reducer, a near joint shaft, a middle finger section, a far joint shaft, a tail-end finger section, a unilateral-coupling transmission mechanism, an underactuated transmission mechanism and a spring piece. In the device, a single tendon rope coupling transmission mechanism, a self-adaption transmission mechanism and the spring piece are adopted to comprehensively realize a composite underactuated capture mode formed by combining coupling capture and self-adaption capture; as the single tendon rope coupling transmission mechanism does not interfere the self-adaption capture process, the decoupling mode is very natural, so that the internal power consumption in the capture process is reduced to the maximum extent and the transmission efficiency is reduced; the capture process of the device is humanized and the finger device has self-adaption capability to the size of the captured object; the finger device has a simple structure, low cost and little energy consumption, is easy to control, has similar appearance and action as the hands of a human body and is suitable for the humanoid robot hands.

Belonging to the technical field of anthropomorphic robots, a transitional underactuated robot finger device with gears and belt wheels mainly comprises a base seat, a motor, a reducer, a first and a second gears, a near joint shaft, a middle finger section, a far joint shaft and a terminal finger section. The device also comprises a driving gear, first and second transitional gears, a driving wheel, a transmission part, a driven wheel, a driven gear, a spring part and first and second transitional shafts. The device utilizes the designed belt wheel and gear transmission mechanism, the movably socketed middle finger section and the decoupling function of the spring part to comprehensively realize the special effect that the double-joint underactuated finger is bent to grasp an object; the structure is simple and reliable, the cost is low, and assembly and maintenance are convenient; similar to the human fingers, the device can be used on a robot hand with the long middle finger sections of fingers and particularly used as the thumb of the anthropomorphic robot hand; when the middle finger section is hindered while touching an object, the terminal finger section can continue to move and grasp the object, and the device can be self-adapted to the shape and size of the grasped object.

Belonging to the technical field of anthropomorphic robots, a tri-joint underactuated robot little finger device comprises a base seat, a motor, a near joint shaft, first and second middle finger sections, a middle joint shaft, a far joint shaft and a terminal finger section. The device also comprises a driven gear, first and second driving gears, a near transitional gear, a driving wheel, a transmission part, a driven wheel, a far transitional gear, first and second spring parts, a first near transitional shaft, a first far transitional shaft and a second transitional shaft. The device utilizes the designed gear and belt wheel transmission mechanism, two movably socketed middle finger sections and the decoupling function of two spring parts to comprehensively realize the special effect of that the tri-joint underactuated finger is bent to grasp an object. Similar to the human fingers, the device can be used on a robot hand with the long first middle finger sections and short second middle finger sections of fingers and particularly used as the little finger of the anthropomorphic robot hand, so that the anthropomorphic robot hand can use less actuators to drive more rotating joints, and can be self-adapted to the shape and size of the grasped object.

The invention relates to a connecting-rod-type underactuated robot finger mechanism with all-rotational joints and aims to solve the problem that the conventional finger mechanism is small in grasping force and not easy to manufacture and maintain. The finger mechanism is characterized in that the upper part of a first connecting rod is hinged to a second connecting rod; the lower part of the first connecting rod is hinged to a third connecting rod driven by a motor and a speed reducer; the tail end of the third connecting rod is hinged to a fourth connecting rod; a spring is mounted between the third connecting rod and the fourth connecting rod; the tail end of the fourth connecting rod is hinged to a fifth connecting rod and a seventh connecting rod respectively; a spring is mounted between the fifth connecting rod and the seventh connecting rod; a sixth connecting rod which takes the shape of an non-isosceles triangle I with a big obtuse angle is hinged between the tail end of the fifth connecting rod and the tail end of the second connecting rod; the vertex angle of the non-isosceles triangle I is hinged to the tail end of the second connecting rod; the short-edge base angle of the non-isosceles triangle I is hinged to the tail end of the fifth connecting rod; the long-edge base angle of the non-isosceles triangle I is hinged to an eighth connecting rod which takes the shape of an non-isosceles triangle II with a small obtuse angle; the vertex angle of the non-isosceles triangle II is hinged to the long-edge base angle of the non-isosceles triangle I; the short-edge base angle of the non-isosceles triangle II is hinged to the tail end of the seventh connecting rod. The finger mechanism has the advantages that the grasping force is large; the adaptability is good; the drive and the control are simple; the manufacture and the maintenance are easy.

The invention discloses an underactuated robot finger multi-joint any-angle immediate synchronous locking device, and belongs to the technical field of robot hands. The device comprises a base, N finger segments, N joint shafts, a motor, a transmission mechanism, a sliding frame, a driving shaft, a driving wheel, Q driven wheels and a Q-stage connecting rod assembly; according to the device, the mechanical finger multi-joint any angle position immediate synchronous locking function is achieved, finger springback instability is prevented, and during object grabbing, object collision and objectextrusion away can be prevented; on the other hand, larger grabbing force can be provided, and lifting of a heavy object can be achieved; grabbing after locking is achieved, the device can be used forgrabbing fragile objects, and the damage to the objects can be reduced; after all joints are locked, the first joint is opened, and the efficiency of grabbing the same kind of objects again can be improved; the locking mechanism is independent of a self-adaptation underactuated finger, and the locking mechanism can be simply transplanted and used in various self-adaptation underactuated fingers,advantages of original fingers can be kept, the structure is simple, the size is small, and control is easy.

The invention discloses a single drive source three-degree-of-freedom underactuated robot wrist device. The single drive source three-degree-of-freedom underactuated robot wrist device comprises a box body which is provided with inner space, a tail end connecting rod, a rotating connecting rod, a thumb, a fixed idler pulley part, a first rope and a second rope, one end of the tail end connecting rod is connected with the thumb through the rotating connecting rod, and the other end of the tail end connecting rod is fixedly connected with the fixed idler pulley part, the first rope and the second rope which are arranged on the tail end connecting rod in sequence. In this way, the invention can provide the single drive source three-degree-of-freedom underactuated robot wrist device, the ropes which are driven by a single drive source are taken as input ends, by means of transmission through an underactuated system, the tail end connecting rod which is taken as an output end is driven to do three-degree-of-freedom movement, a robot formed in this way is less in power source, the size of the wrist is smaller than that in the prior art, the weight is light, the cost is low, and the good practical performance is achieved.

The invention discloses a finger device for a double-joint three-axis-wheel combined underactuated robot, which belongs to the technical field of bionic robotic hands. The finger device comprises a base, a motor, a reducer, a base shaft, a near joint shaft, a middle finger section, a far joint shaft, a tail end finger, multiple transmission mechanisms and springs. With the single motor, multiple shafts, multiple transmission mechanisms with different transmission ratios, springs and the like, the finger device achieves the combined underactuated catching advantages that: fingers are coupled and turn to an object to be caught, and self-adaptively catch the object; the catching process is like that of a human hand, the action is flexible, the catching of the object is stable, objects of different sizes and shapes can be caught in a self-adaptive manner, the requirement on the control system is low, and the manipulation is easy; meanwhile, the structure is simple and compact, the energy consumption is low, the transmission efficiency is high, the cost is low, the assembly and maintenance are convenient, the shape of the finger device is similar with a human hand, and the finger device is suitable to be used as a hand of a bionic robot.

The invention belongs to the technical field of robots, and in particular relates to a horizontal clamping self-adaptive three-finger underactuated robot hand. The flat clamp self-adaptive three-finger underactuated robot hand which has six degrees of freedom is composed of a base and three underactuated fingers. The three underactuated fingers comprise the first finger, the second finger and thethird finger. The three fingers are mounted in the base in triangular distribution and are fixedly connected together to the base through screws. The three underactuated fingers are totally same in structural dimension and are driven by drivers, gear transmission structures, connecting rod mechanisms and gear and rack mechanisms, so that one motor controls two joints of the fingers. The hand in acompound grabbing mode of clamping objects of different shapes and dimensions horizontally and enveloping the objects of different shapes and dimensions self-adaptively is compact in structure, high in integration level, low in manufacturing and maintenance cost and large in grabbing range, and can be used as an end executor of an intelligent robot.

Belonging to the technical field of anthropomorphic robots, a transitional underactuated robot finger device with gears and belt wheels mainly comprises a base seat, a motor, a reducer, a first and asecond gears, a near joint shaft, a middle finger section, a far joint shaft and a terminal finger section. The device also comprises a driving gear, first and second transitional gears, a driving wheel, a transmission part, a driven wheel, a driven gear, a spring part and first and second transitional shafts. The device utilizes the designed belt wheel and gear transmission mechanism, the movablysocketed middle finger section and the decoupling function of the spring part to comprehensively realize the special effect that the double-joint underactuated finger is bent to grasp an object; thestructure is simple and reliable, the cost is low, and assembly and maintenance are convenient; similar to the human fingers, the device can be used on a robot hand with the long middle finger sections of fingers and particularly used as the thumb of the anthropomorphic robot hand; when the middle finger section is hindered while touching an object, the terminal finger section can continue to moveand grasp the object, and the device can be self-adapted to the shape and size of the grasped object.

The invention discloses an underactuated robot finger device based on rope winding. The problem that in the prior art, an anthropomorphic robot finger still needs to be improved is solved. The underactuated robot finger device comprises a base outer shell, a first finger middle shell, a second finger middle shell and a finger tail shell which are hinged in sequence, and loosening reset springs arearranged at hinged positions; one end of the base outer shell is connected with a mechanical arm, and the other end of the base outer shell is provided with a gripping control motor, a first universal joint, a gripping adjustment driving wheel, a gripping adjustment spring, a pull rope, a pull rope winding device, a pull rope straight sleeve and an arc-shaped pull rope positioning sleeve; a second universal joint and a first gripping adjustment driven wheel are arranged at the hinged position of the first finger middle shell and the second finger middle shell; and a third universal joint anda second gripping adjustment driven wheel are arranged at the hinged position of the second finger middle shell and the finger tail shell. According to the technology, the effect of muscle stretchingis simulated by producing tensile force by winding two pull ropes to shorten the length in a vertical direction.