CN103331759B - Large-allowance capturing mechanism for end effector of spatial large manipulator - Google Patents

Abstract

A large-tolerance capture mechanism for an end effector of a large-scale mechanical arm in space relates to a large-tolerance capture mechanism. The invention aims to solve the problem that the existing space large manipulator arm end effector mechanism and control system are complicated and the reliability of space application is reduced. Each linear sliding bearing guide rod is equipped with a linear sliding bearing, and the finger installation platform is slidingly connected with three linear sliding bearing guide rods through three linear sliding bearings. The center of the platform is elastically connected with the ball screw nut through the nut floating spring; one end of each main link is connected to the finger installation platform in rotation, the other end of each main link is connected to the finger in rotation, and each auxiliary link One end is rotatably connected with the finger mounting platform, and the other end of each secondary connecting rod is rotatably connected with the finger. The high tolerance capture mechanism of the present invention is used to capture space on rail end effectors.

Description

High Tolerance Capture Mechanism for Spatially Large Manipulator Arm End Effector

technical field

The invention relates to a large-tolerance capture mechanism of a large mechanical arm end effector.

Background technique

Existing end-effectors of large space manipulators are relatively complex space and aerospace mechanisms. In order to complete the capture of space loads, the end effector of the large space manipulator needs to be able to capture the load when the capture interface has a large displacement and angular deviation relative to the end effector. Therefore, one of the main properties of the space large manipulator The requirement is a large tolerance. The large-tolerance performance requirements enable the complete positioning and constraints of the interface after the end-effector of the large robotic arm captures the load.

The existing large-scale space manipulator end effector is composed of multiple links, mainly including capture link, positioning constraint link, etc. Finally, in order to increase the connection stiffness between the end effector and the capture load interface, an additional locking link is required. The above-mentioned multiple links will require a separate drive system and control system, which increases the complexity of the mechanism and control system of the end effector and reduces the reliability of space applications.

To sum up, the existing end-effector mechanism and control system of large space manipulators are complicated, which reduces the reliability of space applications.

Contents of the invention

The present invention solves the problem that the existing end effector mechanism and control system of a large space manipulator is complex and reduces the reliability of space applications, and further provides a large tolerance capture mechanism for the end effector of a space large manipulator.

The technical scheme that the present invention takes for solving the problems of the technologies described above is:

The large-tolerance capture mechanism for the end effector of a large-scale mechanical arm of the present invention includes an end effector and a target interface device, and the end effector includes an end cover, a support cylinder, a finger mounting platform, a ball screw, a reversing gear, Drive motor, ball screw nut, nut floating spring, three main links, three secondary links, three mechanical limit pins, fingers, spacer, pinion, three linear sliding bearings, and three linear sliding bearing guides rod;

The end cover is connected to the upper end surface of the support cylinder by threads, and three guide taper holes are evenly distributed along the circumferential direction on the end cover. The upper end of the ball screw is installed at the center of the end cover, the lower end of the ball screw passes through the center through hole of the partition and is installed on the partition, the ball screw nut is installed on the ball screw and is located between the end cover and the partition Between them, the reversing gear is fixed on the lower end of the ball screw, the upper end of the driving motor is clamped on the partition plate, and a pinion is installed on the output shaft of the driving motor, and the pinion and the reversing gear mesh with each other;

Three linear sliding bearing guide rods are vertically and uniformly arranged on the upper end surface of the partition along the circumferential direction of the partition, and the upper ends of the three linear sliding bearing guide rods are all installed on the lower end surface of the end cover, and each linear sliding bearing guide rod A linear sliding bearing is installed on the top, and the finger mounting platform is slidingly connected with three linear sliding bearing guide rods through three linear sliding bearings. The outer wall of the ball screw nut is equipped with a nut floating spring, and the center of the finger mounting platform is passed through the nut floating spring. Slightly floating elastic connection with the ball screw nut;

One end of each main link is rotatably connected to the finger mounting platform, the other end of each main link is rotatably connected to the finger, one end of each secondary link is rotatably connected to the finger mounting platform, and the other end of each secondary link is rotatably connected to the finger mounting platform. The fingers are rotated and connected, and a mechanical limit pin is installed on the lower end of each finger. The mechanical limit pin is located between the corresponding main link and the secondary link. One end of each secondary link is connected to the finger installation platform. A torsion spring is installed at the rotating joint;

The interface device is composed of an interface body and three positioning cones. The interface body is a three-lobe structure. The three positioning cones are evenly arranged on the lower end surface of the interface body. The three positioning cones are integrated with the interface body. The three positioning cones The three guide taper holes are arranged in one-to-one correspondence, and the lower end of the interface device is arranged corresponding to the upper end of the end effector.

The beneficial effects of the present invention are:

The large-tolerance capture mechanism for the end effector of a large-scale mechanical arm of the present invention uses a connecting rod to couple and drive three fingers, and converts the rotation of the motor into a reciprocating linear motion of the finger mounting platform through a screw nut mechanism, and through the connecting rod coupling The opening and closing of the fingers is realized under the comprehensive action of , torsion spring drive and housing constraints, and through the optimized design of the wedge-shaped groove of the interface, the opening of the wedge-shaped groove is maximized, so that the end effector has the largest possible tolerance capacity, Compared with the existing capture mechanism of the end effector, the tolerance is large, and the reliability of the space application is greatly improved, and the reliability is increased by more than 30%;

The large-tolerance capture mechanism used for the end effector of a large-scale mechanical arm of the present invention completes the capture of the docking port through the passive finger mechanism coupled with the connecting rod, and completes the capture, positioning and electrical connection of the docking port through a set of drive systems. , compared with the existing large-scale mechanical arm end effectors that can only realize the capture, positioning and electrical connection of the interface through multiple links, the capture mechanism and control system of the present invention are simple in structure and strong in controllability;

The three positioning cones and the three guiding cone holes of the large-tolerance capture mechanism used for the end effector of the large space manipulator of the present invention are arranged in one-to-one correspondence, which can prevent the interface from the end effector when the positioning accuracy of the space large manipulator is not high. When there is a large position and attitude deviation between them, the capture operation of the end effector to the interface is realized;

The finger of the large-tolerance capture mechanism for the end effector of a large-scale mechanical arm of the present invention can quickly complete the process from unfolding to closing, ensuring that the output torque of the drive system of the end effector is sufficient, and can quickly realize the capture of the interface;

The large-tolerance capture mechanism for the end effector of a large space manipulator of the present invention can be applied to the field of space on-orbit service.

Description of drawings

Fig. 1 is a front sectional view of a large-tolerance capture mechanism for a large-scale manipulator end effector of the present invention, and Fig. 2 is a perspective view of a large-tolerance capture mechanism for a large-space manipulator end-effector of the present invention, Fig. 3 is a three-dimensional diagram of the installation relationship between fingers 1-20, finger mounting platform 1-3 and finger mounting platform 1-3 and lead screw nut when three sets of fingers 1-20 are closed in the first embodiment; Fig. 4 is DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS When the three sets of fingers 1-20 are unfolded, the three-dimensional diagram of the installation relationship between the fingers 1-20, the finger mounting platform 1-3, and the finger mounting platform 1-3 and the lead screw nut; FIG. 5 is an end effector Schematic diagram of the process of the capture interface (before capture); Fig. 6 is a schematic diagram of the process of the capture interface of the end effector (during capture); Fig. 7 is a schematic diagram of the process of the capture interface of the end effector (after capture); Fig. 8 is a specific embodiment one A three-dimensional perspective view of the interface device 2; FIG. 9 is a cross-sectional view of the interface device 2 in the first specific embodiment; FIG. 10 is a large-tolerance capture mechanism for the end effector of a large space manipulator of the present invention installed in a large space on-orbit maintenance Schematic diagram of the connections at the end of the robotic arm.

Detailed ways

Embodiment 1: As shown in Figures 1 to 10, the large-tolerance capture mechanism for the end effector of a large space manipulator in this embodiment includes an end effector 1 and a target interface device 2, and the end effector 1 includes an end cover 1-1, support cylinder 1-2, finger mounting platform 1-3, ball screw 1-6, reversing gear 1-9, drive motor 1-10, ball screw nut 1-11, nut floating spring 1 -12, three main connecting rods 1-15, three auxiliary connecting rods 1-16, three mechanical limit pins 1-18, fingers 1-20, partitions 1-22, pinion gears 1-23, three Linear sliding bearings 1-4 and three linear sliding bearing guide rods 1-5;

The end cover 1-1 is threaded on the upper end surface of the support cylinder 1-2, and three guide taper holes 1-21 are uniformly processed along the circumferential direction on the end cover 1-1, and the partition plate 1-22 is fixed horizontally on the The lower part of the support cylinder 1-2, the central through hole is processed on the partition 1-22, the upper end of the ball screw 1-6 is installed at the center of the end cover 1-1, and the lower end of the ball screw 1-6 passes through The central through hole of the partition 1-22 is installed on the partition 1-22, the ball screw nut 1-11 is installed on the ball screw 1-6 and is located between the end cover 1-1 and the partition 1-22 , the reversing gear 1-9 is fixed on the lower end of the ball screw 1-6, the upper end of the driving motor 1-10 is clamped on the partition 1-22, and the output shaft of the driving motor 1-10 is equipped with a pinion 1 -23, the pinion gear 1-23 meshes with the reversing gear 1-9;

Three linear sliding bearing guide rods 1-5 are vertically and uniformly arranged on the upper end surface of the partition plate 1-22 along the circumferential direction of the partition plate 1-22, and the upper ends of the three linear sliding bearing guide rods 1-5 are installed on the end cover On the lower end surface of 1-1, each linear sliding bearing guide rod 1-5 is equipped with a linear sliding bearing 1-4, and the finger installation platform 1-3 passes through three linear sliding bearings 1-4 and three linear sliding bearings The guide rod 1-5 is slidingly connected, the outer wall of the ball screw nut 1-11 is covered with a nut floating spring 1-12, and the center of the finger mounting platform 1-3 passes through the nut floating spring 1-12 and the ball screw nut 1-11 Micro-floating elastic connection;

One end of each main link 1-15 is rotatably connected with the finger mounting platform 1-3, the other end of each main link 1-15 is rotatably connected with the fingers 1-20, and one end of each secondary link 1-16 is rotatably connected with The finger installation platform 1-3 is rotationally connected, and the other end of each secondary connecting rod 1-16 is rotationally connected with the finger 1-20, and a mechanical limit pin 1-18 is installed on the lower end of each finger 1-20. Position pins 1-18 are located between corresponding main connecting rods 1-15 and auxiliary connecting rods 1-16, and one end of each auxiliary connecting rod 1-16 is installed at the rotating joint connected with finger mounting platform 1-3. torsion spring;

The interface device 2 is composed of an interface main body 2-1 and three positioning cones 2-2. The interface main body 2-1 has a three-lobed structure, and the three positioning cones 2-2 are evenly arranged on the lower end surface of the interface main body 2-1. , the three positioning cones 2-2 are integrated with the interface main body 2-1, the three positioning cones 2-2 are set in one-to-one correspondence with the three guide cone holes 1-21, the lower end of the interface device 2 is connected to the end effector 1 The upper end corresponds to the setting.

The interface body 2-1 has a V-shaped wedge-shaped groove with a large opening with a limit size between the petals of the three-lobe structure; the interface device 2 is composed of the interface body 2-1 and three positioning cones 2-2, the interface body 2-1 It is a three-lobed structure, and the opening size of the wedge-shaped slot between the petals is maximized, reaching the limit value, so that the end effector system has a larger tolerance range as much as possible, that is, when the interface and the end effector time In the case of a large position and attitude deviation, the end effector can also realize the capture of the interface; when capturing, the three sets of fingers 1-20 correspond to a wedge-shaped slot on the interface device 2, and the fingers 1-20 and The cooperation of the wedge-shaped groove completes the deflection correction and capture operation of the end effector on the interface; further fine positioning and electrical connection operations can be realized through the cooperation of the positioning cone on the interface and the tapered positioning hole on the end effector.

The end cover 1-1 and the support cylinder 1-2 are positioned through the joint and connected by screws; the finger mounting platform 1-3 is fixedly connected with three sets of non-metallic self-lubricating linear sliding bearings 1-4, and the finger mounting platform 1- 3. The reciprocating motion can be realized on the linear sliding bearing guide rod 1-5; one end of the three sets of linear bearing guide rods 1-5 is fixed on the end cover 1-1, and the other end is fixed on the partition 1-22; the ball screw 1- 6 Supported by the first angular contact thin-walled bearing 1-7 and the second angular contact thin-walled bearing 1-8, the angular contact bearings 1-7 and 1-8 are installed face-to-face; by driving the motor 1-10 on the output shaft The meshing of the pinion gear and the reversing gear 1-9 realizes the rotation of the ball screw 1-6, so that the rotation of the ball screw 1-6 is converted into a straight line of the finger mounting platform 1-3 through the ball screw nut 1-11 Reciprocating motion realizes the unfolding and closing of the fingers 1-20 and the final positioning of the load; the driving motor 1-10 is installed at the lower part of the support cylinder 1-2;

The driving motor 1-10 is composed of a double-winding DC brushless motor, a harmonic reducer, an electromagnetic brake, a resolver and an output pinion; the ball screw nut 1-11 is installed in a micro-floating manner through the nut floating spring 1-12 Finger installation platform 1-3;

The interface device 2 is composed of an interface main body and a positioning cone, wherein the interface main body is a three-lobed structure, and the V-shaped wedge-shaped groove between the petals has been optimized to make the end effector have as strong a tolerance as possible;

When the fingers of the end effector are fully unfolded to form an envelope capture space, the finger mounting platform 1-3 reaches the top of the end effector under the action of the ball screw 1-6 and the ball screw nut 1-11, and this When the first main link shaft 1-14 and the first auxiliary link shaft 1-13 are separated from the constraints of the support cylinder 1-2 and the end cover 1-1, the fingers 1-20 are on the first auxiliary link shaft 1-13 The expansion is realized under the action of the torsion spring between the finger installation platform 1-3; when the drive motor 1-10 drives the ball screw to rotate through the reversing gear 1-9, and under the action of the ball screw nut 1-11, the finger The installation platform 1-3 moves upwards to realize the process that the three sets of fingers 1-20 of the end effector protrude out of the support cylinder 1-2, and finally unfold to form an envelope capture space or implement the process of releasing the load interface;

On the contrary, when the finger mounting platform 1-3 is under the action of the ball screw system, the ball screw system drives the finger mounting platform 1-3 to move downward, the first main link shaft 1-14, the first auxiliary link shaft 1- 13 gradually enters the support cylinder 1-2 and the end cover 1-1, when the first main link shaft 1-14 and the first auxiliary link shaft 1-13 enter the housing, the fingers 1-20 start to close, and the 3 Fingers 1-20 respectively enter into their corresponding V-shaped wedge-shaped grooves. At the initial entry stage, because there is a certain gap between the main connecting rod 1-15 supporting cylinder 1-2, fingers 1-20 are not completely vertical at this time. In the straight state, as the finger support platform 1-3 continues to move down, the finger 1-20 gradually approaches the vertical state (as shown in Figure 6), and the mechanical stop pin 1-18 is used to prevent the Before the rod shaft 1-17 and the second auxiliary connecting rod shaft 1-19 enter the inside of the support cylinder 1-2 (that is, the second main connecting rod shaft 1-17 and the second auxiliary connecting rod shaft 1-19 are not supported Constraints of the barrel 1-2) The fingers 1-20 are reversed to avoid the failure of the interface capture;

As the finger installation platform 1-3 continues to enter, the end effector draws closer to the axial distance between the interface device 2 and the end effector, and finally the guide taper hole 1-21 of the end cover 1-1 and the interface device 2 Under the action of the positioning cone 2-1 on the top, the precise positioning and complete restraint of the interface are realized, thereby completing the capture of the interface, that is, the capture of the load (as shown in FIG. 7 ).

Embodiment 2: As shown in FIGS. 1-10 , the shape of fingers 1-20 in this embodiment is L-shaped. With such a design, the shape of the L-shaped finger can enable the end effector to quickly form an envelope capture space, thereby implementing fast and reliable capture of the three-lobed mechanical interface. Other components and connections are the same as those in the first embodiment.

Specific Embodiment Three: As shown in Figures 1, 5-7, the linear sliding bearings 1-4 of this embodiment are non-metallic self-lubricating linear sliding bearings. This design is mainly due to the fact that self-lubricating bearings have the advantages of not needing lubrication compared with rolling bearings, and have fewer failure links, small size, and relatively high reliability, which is suitable for the reliability requirements of space mechanisms. Other compositions and connections are the same as those in Embodiment 1 or 2.

Embodiment 4: As shown in Figures 1, 5-7, the drive motor 1-10 in this embodiment is a double-winding DC brushless drive motor. With such a design, the dual-winding brushless DC motor has the characteristics of redundant backup, and the dual-motor backup of the drive system can be realized without additional motors, reducing the mass and volume of the system and improving the reliability of the system to meet the needs of space agencies. Small quality, small volume, high reliability requirements. Other components and connections are the same as those in the third embodiment.

Embodiment 5: As shown in Figures 1, 5-7, the capture mechanism described in this embodiment also includes a first angular contact thin-walled bearing 1-7, a second angular contact thin-walled bearing 1-8, and a ball screw 1 The lower part of -6 is installed on the partition 1-22 through the first angular contact thin-walled bearing 1-7 and the second angular contact thin-walled bearing 1-8. Such a design, such a design, adopts such a ball screw installation method, which can improve the axial bearing capacity of the screw and reduce the impact of the captured impact on the ball screw. Other compositions and connections are the same as those in Embodiment 1, 2 or 4.

Specific embodiment six: As shown in Figures 1, 5-7, the first angular contact thin-walled bearing 1-7 and the second angular contact thin-walled bearing 1-8 of this embodiment are installed face-to-face on the separator 1-8 from top to bottom 22 on. With such a design, the angular contact bearings are arranged face to face, which can increase the installation rigidity of the ball screw and further increase the axial bearing capacity of the screw. Other compositions and connections are the same as those in Embodiment 5.

Embodiment 7: As shown in Figures 1, 3-7, the capture mechanism in this embodiment also includes three first main link shafts 1-14 and three second main link shafts 1-17, each The lower end of the main link 1-15 is installed on the finger mounting platform 1-3 through a first main link shaft 1-14, and the upper end of each main link 1-15 is passed through a second main link shaft 1-17 Installed on the lower end corresponding to fingers 1-20. With such a design, a rolling hinge is realized between the main link and the finger and the finger installation platform, thereby improving the smoothness of finger movement. Other compositions and connections are the same as those in Embodiment 1, 2, 4 or 6.

Embodiment 8: In this embodiment, both ends of the first main link shaft 1-14 and the second main link shaft 1-17 are connected to the finger mounting platform 1-3 by metal self-lubricating sliding bearings. With such a design, the self-lubricating bearing can also reduce the mass and volume of the system and improve the reliability of the system movement. Other compositions and connections are the same as those in Embodiment 7.

Ninth specific embodiment: As shown in Figures 1, 3-7, the capture mechanism in this embodiment also includes three first secondary link shafts 1-13 and three second secondary link shafts 1-19, each The lower end of the secondary connecting rod 1-16 is installed on the finger installation platform 1-3 through a first secondary connecting rod shaft 1-13, and the upper end of each secondary connecting rod 1-16 passes through a second secondary connecting rod shaft 1-19 Installed on the lower end corresponding to fingers 1-20. Such a design enables the rolling hinge between the secondary link and the fingers and the finger installation platform, assists the main link to improve the smoothness of finger movement, and combines the finger shell to enable the end effector fingers to be closed quickly, thus completing the docking port. Fast envelope capture improves the success rate of payload capture. The other components and connections are the same as those in Embodiment 1, 2, 4, 6 or 7.

Embodiment 10: In this embodiment, both ends of the first secondary connecting rod shaft 1-13 and the second secondary connecting rod shaft 1-19 are connected to the finger mounting platform 1-3 by metal self-lubricating sliding bearings. Such a design also uses self-lubricating bearings to reduce the mass and volume of the system and improve the reliability of the system movement. Other compositions and connections are the same as those in Embodiment 9.

working principle:

The invention is mainly applied to operations such as on-orbit maintenance, load capture and release in space on-orbit service. The end effector 1 in the large-tolerance capture mechanism of the present invention is installed on the end of the large-scale mechanical arm 3 in space, and the capture interface device 2 used in cooperation with the end effector in the present invention is installed on the captured target load (target spaceflight). 5), the large robotic arm 3 is installed on the robotic arm base (space station or tracking spacecraft 4). At the beginning of the docking capture, the base of the manipulator or the target load undergoes a series of on-orbit maneuvers, so that the position and attitude of the base and the target load meet the requirements for the operation of the manipulator; then the manipulator is controlled to position the end effector 1 to the desired position, At the same time, the capture mechanism (finger) of the end effector is deployed. The ideal state of the desired pose is that there is no position and posture deviation between the captured interface and the end effector, and the positioning surfaces between the end effector interfaces are completely fitted, but Due to the poor positioning accuracy of the end effector of the large manipulator, there is usually a large deviation in position and attitude between the interface and the end effector. Therefore, the actual pose to which the end effector is positioned by the manipulator must meet the Capture requirements; when the manipulator reaches the pose required for capture, all joints of the manipulator are locked and stop moving. At this time, the unfolded capture mechanism (finger) has been unfolded to form a capture space for capturing the envelope of the target interface; then the control terminal executes The capture mechanism (finger) of the device is closed to realize the capture of the load and the subsequent positioning and complete restraint operations;

The working principle of the end effector 1 of the present invention is as follows:

When the capture starts, the finger mounting platform 1-3 is near the top of the end effector 1. At this time, the first main link shaft 1-14 and the first secondary link shaft 1-13 of the three sets of finger mechanisms are all disengaged. The constraints of the support cylinder 1-2 and the end cap 1-1, therefore, the three fingers are in the unfolded state (as shown in Figure 5) to form the envelope capture space under the action of the torsion spring; then, the brushless DC motor The driving system 1-10 starts to work, and drives the ball screw 1-6 to rotate through the reversing gear 1-9, and the rotation of the ball screw 1-6 drives the ball screw nut 1-11 to move downward, and the ball screw nut 1- 11 Drive the finger installation platform 1-3 to move downward. When the first main link shaft 1-14 and the first auxiliary link shaft 1-13 start to enter the support cylinder 1-2 and the end cover 1-1, when the first A main connecting rod shaft 1-14 and a first auxiliary connecting rod shaft 1-13 enter the supporting cylinder 1-2, and the three sets of fingers 1-20 all start to close, and the three sets of fingers 1-20 are on the supporting cylinder 1-2 and Under the action of the mechanical limit pin 1-18, it is quickly closed, and the three sets of fingers 1-20 respectively enter the interface device 2 and connect with the three corresponding V-shaped wedge-shaped grooves of the interface device 2;

In the initial entry stage, since there is a certain gap between the main connecting rod 1-15 and the support cylinder 1-2, the fingers 1-20 are not completely in a vertical state at this time, and as the finger support platform 1-3 continues to enter, the fingers 1-20 gradually approaches the vertical state (as shown in Figure 6); as the ball screw 1-6 continues to rotate, the finger mounting platform 1-3 continues to enter the support cylinder 1-2, and the end effector The axial distance between the interface device 2 and the end effector 1 is shortened, and finally under the action of the guide taper hole 1-21 on the end cover 1-1 and the positioning cone 2-1 on the interface device 2, the alignment is realized. The precise positioning and complete constraints of the interface complete the capture of the interface, that is, the capture of the load (as shown in Figure 7).

The deployment and load release process of the end effector is opposite to the above. Compared with the above capture process, during the deployment and load release process, the double-winding brushless DC motor rotates in the opposite direction, and the ball screw is driven by the reversing gear 1-9. 1-6 reverse rotation, under the action of the screw nut 1-11, the finger installation platform 1-3 moves upward linearly, and the three sets of finger mechanisms gradually extend out of the support cylinder 1-2, when the first main link shaft 1 -14. The first auxiliary connecting rod shaft 1-13 is under the constraints of the support cylinder 1-2 and the end cover 1-1, and is affected by the mechanical limit pin 1-18, and the three sets of fingers 1-20 are stretched out in a straight line housing; and when the first main link shaft 1-14 and the first auxiliary link shaft 1-13 are separated from the constraints of the support cylinder 1-2 and the end cover 1-1, the fingers 1-20 are instantly Unfold, and form the capture space or complete the release of the load.

Claims (10)

1. the large tolerance capture mechanism for space large scale computer mechanical arm end effector, described capture mechanism comprises end effector (1) and target interface device (2), end effector (1) comprises end cap (1-1), support cylindrical shell (1-2), finger mounted platform (1-3), ball screw (1-6), tumbler gear (1-9), drive motors (1-10), ball-screw nut (1-11), nut floating spring (1-12), three master connecting-rods (1-15), three slave connecting rods (1-16), three mechanical position limitation pins (1-18), finger (1-20), dividing plate (1-22), pinion (1-23), three linear slide bearings (1-4) and three linear slide bearing guide rods (1-5),

End cap (1-1) is threaded connection on the upper surface supporting cylindrical shell (1-2), on end cap (1-1) along the circumferential direction uniform be processed with three guiding taper holes (1-21), dividing plate (1-22) level is packed in the bottom supporting cylindrical shell (1-2), dividing plate (1-22) is processed with central through hole, the upper end of ball screw (1-6) is arranged on the center of end cap (1-1), the lower end of ball screw (1-6) is passed the central through hole of dividing plate (1-22) and is arranged on dividing plate (1-22), ball-screw nut (1-11) is arranged on ball screw (1-6) and goes up and be positioned between end cap (1-1) and dividing plate (1-22), tumbler gear (1-9) is packed in the lower end of ball screw (1-6), the upper end of drive motors (1-10) is installed on dividing plate (1-22), the output shaft of drive motors (1-10) is provided with pinion (1-23), pinion (1-23) and tumbler gear (1-9) engage each other,

Three linear slide bearing guide rods (1-5) are along the circumferencial direction of dividing plate (1-22) vertically on the uniform upper surface being arranged on dividing plate (1-22), the upper end of three linear slide bearing guide rods (1-5) is installed on the lower surface of end cap (1-1), every root linear slide bearing guide rod (1-5) is coated with a linear slide bearing (1-4), finger mounted platform (1-3) is slidably connected by three linear slide bearings (1-4) and three linear slide bearing guide rods (1-5), the outer wall of ball-screw nut (1-11) is set with nut floating spring (1-12), the center of finger mounted platform (1-3) is connected with ball-screw nut (1-11) micro-floating elastic by nut floating spring (1-12),

It is characterized in that: one end and the finger mounted platform (1-3) of each master connecting-rod (1-15) are rotationally connected, the other end and the finger (1-20) of each master connecting-rod (1-15) are rotationally connected, one end and the finger mounted platform (1-3) of each slave connecting rod (1-16) are rotationally connected, the other end and the finger (1-20) of each slave connecting rod (1-16) are rotationally connected, the lower end of each finger (1-20) is provided with a mechanical position limitation pin (1-18), mechanical position limitation pin (1-18) is positioned between corresponding master connecting-rod (1-15) and slave connecting rod (1-16), the cradle head place that one end of described each slave connecting rod (1-16) is connected with finger mounted platform (1-3) is provided with torsion spring,

Interface arrangement (2) is made up of interface agent (2-1) and three locating cones (2-2), interface agent (2-1) is three-clove style structure, on three uniform lower surfaces being arranged on interface agent (2-1) of locating cone (2-2), three locating cones (2-2) make one with interface agent (2-1), three locating cones (2-2) are arranged with three taper hole (1-21) one_to_one corresponding that lead, and the lower end of interface arrangement (2) is corresponding with the upper end of end effector (1) to be arranged.

2. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 1, is characterized in that: the shape of finger (1-20) is L-shaped.

3. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 1 and 2, is characterized in that: linear slide bearing (1-4) is nonmetal self-lubricating linear sliding bearing.

4. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 3, is characterized in that: drive motors (1-10) is double winding brush DC drive motors.

5. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 1,2 or 4, it is characterized in that: described capture mechanism also comprises the first angular contact thin-wall bearing (1-7) and the second angular contact thin-wall bearing (1-8), the bottom of ball screw (1-6) is arranged on dividing plate (1-22) by the first angular contact thin-wall bearing (1-7) and the second angular contact thin-wall bearing (1-8).

6. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 5, is characterized in that: the first angular contact thin-wall bearing (1-7) and the second angular contact thin-wall bearing (1-8) are from top to bottom arranged on dividing plate (1-22) face-to-face.

7. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 1,2,4 or 6, it is characterized in that: described capture mechanism also comprises three the first master connecting-rod axles (1-14) and three the second master connecting-rod axles (1-17), the lower end of each master connecting-rod (1-15) is arranged on finger mounted platform (1-3) by a first master connecting-rod axle (1-14), and the upper end of each master connecting-rod (1-15) is arranged on the lower end of corresponding finger (1-20) by a second master connecting-rod axle (1-17).

8. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 7, is characterized in that: the first master connecting-rod axle (1-14) all adopts metal self-lubricating sliding bearing to be connected with finger mounted platform (1-3) with the two ends of the second master connecting-rod axle (1-17).

9. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 1,2,4,6 or 8, it is characterized in that: described capture mechanism also comprises three the first slave connecting rod axles (1-13) and three the second slave connecting rod axles (1-19), the lower end of each slave connecting rod (1-16) is arranged on finger mounted platform (1-3) by a first slave connecting rod axle (1-13), and the upper end of each slave connecting rod (1-16) is arranged on the lower end of corresponding finger (1-20) by a second slave connecting rod axle (1-19).

10. the large tolerance capture mechanism for space large scale computer mechanical arm end effector according to claim 9, is characterized in that: the first slave connecting rod axle (1-13) all adopts metal self-lubricating sliding bearing to be connected with finger mounted platform (1-3) with the two ends of the second slave connecting rod axle (1-19).