CN113084701B - Variable-rigidity grinding and polishing execution device and execution method thereof - Google Patents

Abstract

The invention discloses a variable-rigidity grinding and polishing executing device and an executing method thereof, wherein the variable-rigidity grinding and polishing executing device comprises a frame module, a rigidity adjusting motor module, a floating module and a pulley module, the frame module comprises a near-end frame, a far-end frame and a supporting frame, the upper end surface of the near-end frame is fixedly connected with the tail end of a mechanical arm, the rigidity adjusting motor module is arranged in the middle of the near-end frame, the floating module is arranged in the frame module and comprises a motor base, elastic pieces and sliding shafts, the sliding shafts are respectively in guiding fit with sliding grooves of the floating modules on the corresponding supporting frames, the elastic pieces are respectively supported and erected through the corresponding pulley modules, the rigidity adjusting motor module drives the pulley module to operate, and the relative distance between the connecting ends and the supporting ends of the elastic pieces of the floating modules is changed, so that the function of changing rigidity is realized. The invention can realize constant force or variable force grinding according to requirements in various occasions, has small negative influence on the flexibility of the mechanical arm, and has the advantages of small volume, low delay and accurate rigidity value.

Description

Variable-rigidity grinding and polishing execution device and execution method thereof

Technical Field

The invention relates to the field of robot grinding and polishing processing, in particular to a variable-rigidity grinding and polishing executing device and a variable-rigidity grinding and polishing executing method.

Background

For the occasions with high requirements on the surface quality of the workpiece, the force control characteristic of the grinding and polishing device is an important index for measuring the comprehensive performance of the grinding and polishing device. Compared with the traditional rigid or flexible fixed-rigidity grinding and polishing device, the variable-rigidity grinding and polishing device can be automatically adjusted to proper rigidity according to the specific requirements of the hardness and contact force of the surface of a workpiece to be processed. In addition, in order to realize the adjustment of the contact force in the grinding and polishing process, the fixed rigidity device only has one way of adjusting the deformation amount, and the variable rigidity device has two ways of adjusting the deformation amount and the rigidity. The variable stiffness device has obvious advantages in adaptability to different workpieces to be processed and force control performance in the processing process of the workpieces.

The realization mode of the variable stiffness can be divided into three methods of adopting materials with nonlinear force and deformation, changing the stiffness through a mechanical structure and changing the material property. The material used in the first method can be equivalent to a variable rate spring, the rate of which increases with the amount of deformation. The variable-rigidity structure designed by the method is simple. However, it cannot realize active adjustment of stiffness, and a large amount of energy is consumed in the stiffness adjustment process. The second method requires a stiffness-adjusting motor to achieve stiffness variation. For example, chinese utility model patent application No. CN 201820924506.5: a variable-rigidity flexible gripping device. The device adjusts the rigidity by changing the angle of the branched chain of the flexible mechanism on the clamping claw arm. The device has kept mechanical transmission variable rigidity device low delay and high accuracy's advantage, but its X direction and Z direction size are great (this utility model patent uses the orbital direction of clamping jaw removal as the X axle, uses the direction of flexible branch chain as the Z axle). If the six-axis mechanical arm is arranged at the tail end of the six-axis mechanical arm, the negative influence on the flexibility of the mechanical arm is large. In addition, when the rigidity is adjusted, the rigidity in the X-axis direction increases, which causes the rigidity in the Y-axis direction to decrease, thereby decreasing the ability to resist the disturbance force in this direction. The rigidity of the material used in the third method is affected by factors such as temperature, air pressure, current magnitude, magnetic field strength and the like, and the third method is currently the most common variable rigidity method for the tail end of the mechanical arm. For example, chinese patent application No. CN 201910812028.8: a magnetorheological fluid rigidity-variable flexible clamping jaw. The device changes the property of the magnetorheological fluid by changing the magnitude of the external magnetic field, and further changes the rigidity of the clamping jaw. The device is small in mass and occupied space, and can better ensure the flexibility of the mechanical arm when being installed at the tail end of the six-axis mechanical arm. However, the magnetorheological fluid has high requirements on the working environment and is easily influenced by the environmental magnetic field. Both of the above patents have a function of changing stiffness, but they both belong to a gripping device, and do not combine the function of changing stiffness with a polishing device, nor do they achieve the normal direction variable stiffness required by the polishing device.

However, as technology advances and those skilled in the art are exploring, some examples of combining the variable stiffness function with the polishing device have appeared. For example, chinese patent application No. CN 201910155330.0: variable-rigidity constant-force floating polishing grinding head. The pneumatic mode is adopted, the friction force of internal interference particles is changed by changing the air pressure, and the rigidity of the polishing head is further adjusted. However, the disadvantages of this device are: the accurate rigidity value of the internal interference particle structure is difficult to directly measure, deformation quantity and contact force are measured by a distance sensor and a force sensor, and then the deformation quantity and the contact force can be obtained by calculation. This device also has virtually no means for measuring the type variable, only means for measuring the contact force. In addition, the pneumatic stiffness-variable device is easy to form a high-temperature and high-pressure environment in repeated inflation, deflation and compression processes, and has higher requirements on the performance of an inner wall material needing to bear air pressure, and the problem is not improved by the device. Therefore, it is particularly important to develop a variable-stiffness polishing actuating mechanism and method which have the advantages of small volume, wide application range, low delay and accurate stiffness value.

Disclosure of Invention

The invention aims to make up for the defects of the prior art, and provides a variable-rigidity grinding and polishing executing device and an executing method thereof, which are suitable for the tail ends of various mechanical arms, can realize constant-force or variable-force grinding as required in various occasions by virtue of the characteristic of high flexibility of the mechanical arms, have small negative influence on the flexibility of the mechanical arms, and have the advantages of small volume, low delay and accurate rigidity value.

The invention is realized by the following technical scheme:

a variable-rigidity grinding and polishing executing device comprises a frame module, a rigidity-adjusting motor module, a floating module and pulley modules, wherein the frame module comprises a near-end frame and a far-end frame which are arranged at an upper interval and a lower interval, the near-end frame and the far-end frame are supported and erected through surrounding supporting frames, the upper end face of the near-end frame is connected and fixed with the tail end of a mechanical arm, a distance sensor is further arranged on the upper end face of the near-end frame, the rigidity-adjusting motor module is arranged in the middle of the near-end frame, the floating module is arranged in the frame module and comprises a motor base used for installing a grinding motor, elastic sheets and sliding shafts are respectively arranged on the periphery of the motor base, the sliding shafts are respectively in guiding fit with sliding grooves of the floating modules on the surrounding supporting frames of the corresponding frame module, and the elastic sheets are respectively supported and erected through the corresponding pulley modules, the rigidity-adjusting motor module drives the pulley module to run through the transmission mechanism, drives the pulley module to move along the direction of the slide bar track of the frame module, and changes the relative distance between the connecting end and the supporting end of the elastic sheet of the floating module, so that the function of changing rigidity is realized.

The middle part of the near-end frame is provided with a steel adjusting motor preformed hole for installing a steel adjusting motor module, mounting preformed holes for connecting and fixing the tail end of the mechanical arm are distributed around the steel adjusting motor preformed hole, and the mounting preformed holes are distributed in an equal circumference mode by taking the central axis of the steel adjusting motor preformed hole as the center; the periphery of the upper end face of the near-end frame is distributed with upper sliding rod rails, upper roller rails and screw clearance holes for installing and fixing a support frame, the upper sliding rod rails and the upper roller rails are distributed in an equal circumference mode by taking the reserved holes of the stiffness adjusting motor as the center, and the upper roller rails are of a sinking groove structure, are positioned on the lower end face of the near-end frame, are arranged in parallel with the upper sliding rod rails and are positioned on two sides of the upper sliding rod rails; the middle part of distal end frame is equipped with the grinding motor preformed hole that is used for installing grinding motor, the grinding motor preformed hole outside is equipped with rotatory track mount pad, the distribution all around of distal end frame up end has down slide bar track, lower gyro wheel track and is used for installing the screw clearance hole of fixed stay frame, the lower gyro wheel track is the heavy groove structure, and it is located the lower terminal surface of distal end frame, sets up and is located the orbital both sides of down slide bar with the down slide bar track side by side. The support frame is of a [ shape structure, the upper end face and the lower end face of the support frame are respectively provided with a mounting and fixing hole for mounting and fixing the support frame on the near-end frame and the far-end frame, and the middle part of the support frame is provided with a floating module chute which is vertically arranged. The rigidity adjusting motor module comprises a rigidity adjusting motor shell fixedly mounted on the bottom end face of the near-end frame, a planet wheel carrier is mounted in the rigidity adjusting motor shell, the gear transmission assembly is driven by a rigidity adjusting motor above the gear transmission assembly, and the outer side of the planet wheel carrier is connected with a near-end rotating track.

The gear transmission component comprises a planetary gear train formed by three planetary gears in a surrounding mode, the planetary gears are all installed on a planetary gear carrier, an inner gear ring is distributed on the inner side face of the shell of the stiffness adjusting motor and is in transmission engagement with the planetary gears, a sun gear is arranged on the planetary gear train, and the sun gear is installed at the output shaft end of the stiffness adjusting motor. The floating module comprises a motor base, the motor base is square, a polishing motor is installed on the bottom end face of the motor base, a polishing head is installed at the output shaft end of the polishing motor, connecting pieces which are uniformly distributed along the circumference direction of the central line and are fixed with elastic pieces which are uniformly distributed along the circumference direction of the central line and use the center of the motor base as the central line are fixedly installed around the motor base respectively, and sliding shafts for guiding are respectively arranged at the outer end parts of the connecting pieces. The pulley module including the pulley frame of vertical setting, rotate the pulley of installing two upper and lower intervals settings in the pulley frame respectively, pulley frame's last lower extreme is installed near end axle and distal end axle respectively, the guiding axle is installed respectively to the tip of near end axle and distal end axle, install the gyro wheel support on the guiding axle respectively, the gyro wheel support is including the axle sleeve with guiding axle sleeve fit, the gyro wheel axle is installed respectively to the both sides of axle sleeve, the gyro wheel is installed respectively to the tip of gyro wheel axle, the guiding axle of near end axle and the cooperation of the last slide bar track direction of near end frame, and the epaxial gyro wheel of near end and the cooperation of last gyro wheel track direction, the guiding axle of distal end axle and the cooperation of the lower slide bar track direction of distal end frame, and the epaxial gyro wheel of far end and the cooperation of lower gyro wheel track direction. The pulley module is characterized in that a near-end shaft and a far-end shaft of the pulley module are respectively installed on a near-end rotating track and a far-end rotating track above and below the pulley module in a guiding mode, the near-end rotating track is located below a rigidity adjusting motor module above and connected with a planet wheel carrier of the rigidity adjusting motor module, the far-end rotating track is installed on a rotating track installation seat in a rotating mode, guide rods are distributed on the near-end rotating track and the far-end rotating track along the circumference by respectively using a middle fixed sleeve of the near-end rotating track and the far-end rotating track as the center, and guide grooves are respectively formed in the middle of the guide rods. One end of the elastic sheet of the floating module is fixedly connected through the connecting sheet, the other end of the elastic sheet is supported through the pulleys corresponding to the pulley modules, and the relative distance between the connecting end and the supporting end of the elastic sheet is changed along with the movement of the pulley modules, so that the function of changing rigidity is realized. The specific execution method of the variable-rigidity grinding and polishing execution device comprises the following specific steps: (1) mounting a near-end frame and a rigidity-adjusting motor module in the frame module to the tail end of the mechanical arm and fixing, mounting a near-end rotating track below the near-end frame through a rigidity-adjusting motor shell, mounting a far-end rotating track on a rotating track mounting seat of a far-end frame, completely assembling a floating module, inversely mounting a grinding motor in a reserved hole of the grinding motor, extending an output shaft of the grinding motor out of the reserved hole of the grinding motor, mounting a grinding head, penetrating an elastic sheet through a gap between an upper pulley and a lower pulley in a pulley module, and mounting all rollers on a roller bracket to prepare for the step (2); (2) a near-end shaft of the pulley module sequentially penetrates through the near-end rotating rail, the roller bracket and the upper sliding rod rail, and a far-end shaft sequentially penetrates through the far-end rotating rail, the lower sliding rod rail and the roller bracket and is fixed by nuts; fixedly connecting a support frame with a near-end frame and a far-end frame through screws and nuts, and enabling a sliding shaft on a connecting sheet to penetrate through a floating module sliding groove of the support frame; finally, the distance sensor is fixedly connected to the near-end frame through a screw; after the variable-rigidity grinding and polishing actuator is installed, the whole variable-rigidity grinding and polishing actuator can be directly installed at the tail end of the mechanical arm without being disassembled; (3) turning on power supplies of the distance sensor and the stiffness adjusting motor module, detecting and adjusting functions of feedback stiffness and type variables of the distance sensor, and transmitting data into a robot control system; (4) setting a grinding track and required contact force according to the shape and the processing requirement of a workpiece to be processed, wherein the grinding track can be completed according to the self-carried function of a robot control system, and the grinding and polishing contact force can be completed by adjusting the rigidity of a variable-rigidity grinding and polishing executing device and finely adjusting the joint track of the robot; (5) turning on a grinding motor, driving a mechanical arm to execute grinding and polishing operation, and feeding back data of a rotating angle of a stiffness adjusting motor module and data of rigidity and deformation recorded by a distance sensor to a robot control system in the process, wherein the data can be analyzed and optimized by technicians; (6) and after the grinding and polishing operation is finished, the power supply is turned off, the variable-rigidity grinding and polishing executing device is taken down, and other executing devices can be arranged on the mechanical arm to perform the next processing procedure.

The invention adopts the integration of a frame module, a stiffness adjusting motor module, a floating module and a pulley module to form a grinding and polishing structure with adjustable stiffness, wherein the structure forms an integral frame through a support frame by the combination of a near-end frame and a far-end frame; each module is compact in structure, convenient to disassemble and assemble and clear in function, can be integrally taken down and disassembled in modules, can be used for grinding and polishing workpieces with various complex shapes by combining the flexible characteristic of the mechanical arm, can obtain real-time rigidity and deformation data, can directly obtain contact force data by the binding force sensor, can be fed back to a robot control system, is combined with the variable rigidity function of the actuator, further improves the integral force control performance, and can realize constant-force floating polishing or variable-force polishing according to requirements.

The mechanism is characterized in that a transmission mechanism of a planetary gear train is adopted, so that a rigidity adjusting motor drives a rotating rail to rotate, the rigidity of the mechanism is changed, elastic sheets with rigidity changing functions are arranged in a square mode, and the sizes of the mechanism in the X-axis direction and the Y-axis direction are reduced as much as possible (the angular speed direction of a polishing head is taken as the Z-axis direction). The floating module and the pulley module of the mechanism slide on a designated track, and accurate rigidity value and deformation can be measured only by two groups of simple sliding rheostat circuits and fed back in real time for reference of technicians.

The invention has the advantages that:

1. the invention adopts a modular design, each module has compact structure, convenient disassembly and assembly and definite function, and can be integrally taken down and disassembled in modules. On the premise of retaining the advantages of high accuracy, low delay, difficult interference from external environment and the like of a mechanical transmission rigidity adjusting mode, the occupied space is reduced as much as possible.

2. In the invention, the type variable and the action length of the elastic sheet can be directly obtained according to the positions of the floating module 3 and the pulley module 4 on the corresponding tracks, and the rigidity value can be calculated by the action length of the elastic sheet through a correlation formula. Namely, the invention can easily measure the type variable and the rigidity value and has higher precision.

3. The invention has wider application range, can be arranged at the tail ends of various mechanical arms, and can realize the function of smooth grinding and polishing by combining the force sensor. At the moment, the contact force, the rigidity value of the device and the deformation can be directly measured, and the measurement precision can be further improved. The elastic sheet can play a role in vibration isolation, impact on the polishing head cannot be directly transmitted to the force sensor, and the service life of the force sensor is prolonged.

4. In the invention, even if no force sensor is arranged, the contact force can be calculated according to the rigidity value and the deformation quantity, and the force control performance is not greatly influenced.

Description of the drawings:

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of a frame module;

FIG. 3 is an enlarged view of a portion of FIG. 2;

FIG. 4 is a schematic view of a proximal frame;

FIG. 5 is a schematic view of a distal end frame;

FIG. 6 is a cross-sectional view of a stiffness adjusting motor module;

FIG. 7 is a schematic diagram of a floating module;

FIG. 8 is an enlarged view of a portion of the structure of FIG. 7;

FIG. 9 is a schematic view of a pulley module;

FIG. 10 is a schematic view of another embodiment of the present invention;

FIG. 11 is a flow chart of a variable stiffness polishing execution method.

The figures are numbered:

FIG. 1: the device comprises a frame module-1, a stiffness adjusting motor module-2, a floating module-3 and a pulley module-4;

FIG. 2: a proximal frame-1001, a distal frame-1002, a distal rotating track-1003, a distance sensor-1004 and a support frame-1005;

FIG. 3: a floating module chute-1501 and a countersunk hole-1502;

FIG. 4 is a schematic view of: a steel adjusting motor reserved hole-1101, an installation reserved hole-1102, an upper sliding rod rail-1103, an upper roller rail-1104 and a screw clearance hole-1105;

FIG. 5: a grinding motor preformed hole-1201, a lower slide bar track-1203, a screw clearance hole-1205 and a rotating track mounting seat-1206;

FIG. 6: a near-end rotating track-2001, a transmission mechanism-2002, a stiffness adjusting motor output shaft-2003 and a stiffness adjusting motor shell-2004;

FIG. 7 is a schematic view of: motor base-3001, connecting piece-3002 (containing counter bore-3201 and sliding shaft-3202), elastic piece-3003, grinding motor-3004 and grinding head-3005;

FIG. 8: a near-end shaft-4001, a far-end shaft-4002, a pulley frame-4003, a pulley-4004, a roller bracket-4005 and a roller-4006;

FIG. 9: a shaft sleeve-4501 and a roller shaft-4502.

The specific implementation mode is as follows:

see the drawings.

Referring to fig. 1, a rigidity-variable polishing executing device comprises a frame module 1, a stiffness adjusting motor module 2, a floating module 3 and a pulley module 4, wherein the frame module 1 comprises a near-end frame and a far-end frame which are arranged at an interval from top to bottom, the near-end frame and the far-end frame are supported and erected through surrounding supporting frames, the upper end surface of the near-end frame is connected and fixed with the tail end of a mechanical arm, a distance sensor is further arranged on the upper end surface, the stiffness adjusting motor module 3 is arranged in the middle of the near-end frame, the floating module 3 is arranged in the frame module 1 and comprises a motor base used for installing a polishing motor, elastic sheets and sliding shafts are respectively arranged on the periphery of the motor base, the sliding shafts are respectively in guiding fit with sliding grooves of the floating modules 3 on the surrounding supporting frames of the corresponding frame module 1, the elastic sheets are respectively supported and erected through the corresponding pulley modules 4, the stiffness adjusting motor module 2 drives the pulley modules to operate through a transmission mechanism, the floating module is driven to move around the central axis direction of the frame module to a required position to realize the function of changing rigidity; the pulley modules 4 are 4 in total, the structures of the pulley modules are the same, the pulley modules are distributed in an equal circumference mode by taking a central axis as a center, the frame module 1 is static relative to the tail end of the mechanical arm and supports the rigidity adjusting motor module 2 and the pulley modules 4, and the floating module 3 is supported by the pulley modules 4.

With reference to fig. 1, 2, 3 and 4, the frame module 1 is composed of a proximal frame 1001, a distal frame 1002, a distal rotating track 1003, a distance sensor 1004 and a support 1005. A motor preformed hole 1101 for installing a stiffness adjusting motor module is formed in the middle of the near-end frame 1001, preformed mounting holes 1102 for connecting and fixing with the tail end of the mechanical arm are distributed around the motor preformed hole 1101, and the preformed mounting holes 1102 are distributed in an equal circumference mode by taking a central axis as a center; the edge distributes all around of near-end frame up end has and uses the axis to be equal circumference upper slide rail 1103, last gyro wheel track 1104 and the screw clearance hole 1105 that is used for installing fixed support frame that distributes as the center, it is heavy groove structure to go up gyro wheel track 1104, and it is located the lower terminal surface of near-end frame 1001, sets up side by side with last gyro wheel track 1104 and is located the both sides of last gyro wheel track 1103, and wherein the support frame is total 4, and their structures are the same, uses the axis to be equal circumference distribution as the center. The support frame includes a floating module runner 1501 and a counterbore 1502 reserved for installation. The number of the installation reserved holes 1102 is 4, and the installation reserved holes are distributed in an equal circumference mode by taking a central axis as a center; the number of the upper slide rail tracks 1103 is 4, and the upper slide rail tracks are distributed in an equal circumference mode by taking a central axis as a center; the number of the upper roller tracks 1104 is 8, and two sides of each upper sliding rod track 1103 are respectively provided with one upper sliding rod track; the number of the screw clearance holes 1105 is 4, and the screw clearance holes are distributed in an equal circumference by taking the central axis as the center. The supporting frame 1005 is of a [ shape structure, mounting and fixing holes for mounting and fixing on the near-end frame and the far-end frame are respectively arranged on the upper end surface and the lower end surface of the supporting frame, and a floating module chute which is vertically arranged is arranged in the middle of the supporting frame.

With reference to fig. 5, a polishing motor preformed hole 1201 for installing a polishing motor is formed in the middle of the distal end frame 1002, a rotating rail mounting seat 1206 is formed outside the polishing motor preformed hole 1201, a lower slide bar rail 1203, a lower roller rail and a screw clearance hole 1205 for installing a fixed support frame are distributed around the upper end surface of the distal end frame 1002, and the lower roller rail is of a sinking groove structure, is located on the upper end surface of the distal end frame 1002, is arranged in parallel with the lower slide bar rail 1203, and is located on two sides of the lower slide bar rail; wherein the lower slider rail 1203, the lower slider rail 1204, and the screw clearance holes 1205 are distributed at the same positions as the upper slider rail 1103, the upper slider rail 1104, and the screw clearance holes 1105 of the proximal frame 1001.

With reference to fig. 6, the stiffness adjusting motor module 2 is composed of a proximal end rotating track 2001, a transmission mechanism 2002, a stiffness adjusting motor output shaft 2003 and a stiffness adjusting motor housing 2004, the stiffness adjusting motor housing 2004 is arranged on the bottom end face of a proximal end frame, a planetary gear carrier is arranged in the stiffness adjusting motor housing 2004, the power of a gear transmission assembly is driven by a stiffness adjusting motor above the gear transmission assembly, the gear transmission assembly comprises a planetary gear train formed by three planetary gears in a surrounding manner, the planetary gears are all arranged on the planetary gear carrier, an inner gear ring is distributed on the inner side face of the stiffness adjusting motor housing, the inner gear ring is in transmission engagement with the planetary gears, the planetary gear train is provided with a sun gear, and the sun gear is arranged at the output shaft end of the stiffness adjusting motor. The outer side of the planet carrier is connected with a near-end rotating rail 2001, wherein the near-end rotating rail 2001 comprises 4 sliding rails in total, the sliding rails are uniformly distributed in a circle by taking a central axis as a center, and the rail direction is radial. The transmission mechanism 2002 comprises a planetary gear train, a planetary gear carrier of which is fixedly connected with a near-end rotating track 2001, a sun gear of which is fixedly connected with an output shaft of the stiffness adjusting motor, and a gear ring of which is fixedly connected with a housing 2004 of the stiffness adjusting motor.

Referring to fig. 7, the floating module 3 includes a motor base 3001, the motor base 3001 is square, a polishing motor 3004 is installed on a bottom end face of the motor base 3001, a polishing head 3005 is installed at an output shaft end of the polishing motor 3004, connection pieces 3002 uniformly distributed along a circumferential direction of the motor base 3001 with a central axis of the motor base 3001 as a central line are respectively and fixedly installed around the motor base 3001, elastic pieces 3003 uniformly distributed along a circumferential direction of the motor base with the central axis of the motor base as the central line are installed and fixed through the connection pieces 3002, outer ends of the connection pieces 3002 are respectively provided with sliding shafts 3202 for guiding, wherein the motor base 3001 includes 4 screw clearance holes, and is uniformly distributed circumferentially with the central axis as a center. The number of the connecting pieces 3002 is 4, the connecting pieces are identical in structure and are distributed in an equal circumference mode by taking the central axis as the center; each connecting tab 3002 includes 2 counter-sunk holes 3201 and a sliding shaft 3202. The number of the elastic pieces 3003 is 4, the structures of the elastic pieces are the same, and the elastic pieces are distributed in an equal circumference mode by taking the central axis as the center; each of the elastic pieces 3003 includes a clearance hole. An output shaft of the polishing motor 3004 is fixedly connected with the polishing head 3005, the other end of the polishing motor 3004 is fixedly connected with the motor base 3001, the motor base 3001 is fixedly connected with 4 connecting pieces 3002 through screws and nuts, and the 4 connecting pieces 3002 are fixedly connected with the nuts and 4 elastic pieces 3003 through screws.

Referring to fig. 7, the pulley module 4 includes a vertically arranged pulley frame 4003, two pulleys 4004 are rotatably mounted in the pulley frame 4003 at an interval up and down, a near-end shaft 4001 and a far-end shaft 4002 are mounted at the upper and lower ends of the pulley frame 4003, guide shafts are mounted at the ends of the near-end shaft 4001 and the far-end shaft 4002, roller brackets 4005 are mounted on the guide shafts, respectively, each roller bracket 4005 includes a shaft sleeve fitted with the guide shaft sleeve, roller shafts are mounted at the two sides of the shaft sleeve, respectively, rollers 4006 are mounted at the ends of the roller shafts, respectively, the guide shaft of the near-end shaft 4001 is in guide fit with an upper sliding rail 1103 of the near-end frame 1001, the roller 4006 on the near-end shaft 4001 is in guide fit with an upper roller rail 1104, the guide shaft of the far-end shaft 4002 is in guide fit with a lower sliding rail 1203 of the far-end frame 1002, and the roller 4006 on the far-end shaft 4002 is in guide fit with a lower roller rail; the near-end shaft 4001 and the far-end shaft 4002 are respectively guided and mounted on a near-end rotating track 2001 and a far-end rotating track 1003 which are arranged above and below the near-end shaft 4001, the near-end rotating track 2001 is located below an upper motor module and connected with a planetary gear carrier of the motor module, the far-end rotating track 1003 is rotatably mounted on a rotating track mounting seat 1206, the near-end rotating track 2001 and the far-end rotating track 1003 respectively use a guide rod which is circumferentially distributed by taking a middle fixing sleeve of the near-end rotating track 2001 and the far-end rotating track 1003 as a center, and guide grooves are respectively formed in the middle of the guide rod.

Further, each pulley module includes 2 roller supports 4005, which are identical in structure and include a bushing 4501 and a roller shaft 4502. Each pulley module contains 4 rollers 4006, which are identical. Both proximal shaft 4001 and distal shaft 4002 contain shoulders and threads. The pulley frame 4003 includes 2 screw holes, and each pulley module 4 includes two pulleys 4004, which are identical in shape and are mounted on the pulley frame 4003. The roller 4006 is mounted on the roller shaft 4502 of the roller bracket 4005 so as to be rotatable thereabout. Distal rotating track 1003 is mounted on rotating track mount 1206 of distal frame 1002 and is traversed by pulley module 4. The function of the pulley block is to ensure the relative positions of the 4 pulley blocks, so that the pulley blocks are not inclined to influence the rigidity changing performance.

With reference to fig. 1 and 6, the transmission mechanism 2002 in the stiffness-adjusting motor module 2 forms a planetary gear train. The waste of the performance of the servo motor caused by the small rotatable angle of the near-end rotating track 2001 is effectively avoided, the precision of rigidity adjustment is improved, and meanwhile, the occupied space is reduced as much as possible.

In conjunction with fig. 1 and 2, 3, and 6, the distance sensor 1004 is conveniently mounted in a position to simultaneously monitor the positions of the floating module 3 and the sliding module 4 in the respective tracks. Here, corresponding devices can be installed at corresponding positions of the floating module 3 and the pulley module 4 for non-contact distance monitoring, and wires can be connected to corresponding positions to form a closed loop containing a slide rheostat for monitoring. Besides, the rigidity value can be measured by the rotation angle value fed back by the servo motor.

With reference to fig. 1, 4 and 6, the priming motor housing 2004 may pass through the priming motor pre-cut hole 1101 in the proximal frame 1001. And the stiffness adjusting motor shell comprises 4 mounting preformed holes which are matched with the mounting preformed holes 1102 on the near-end frame and can be mounted at the tail end of the mechanical arm together.

With reference to fig. 1, 2 and 7, the sliding shaft 3202 on the connecting plate 3002 can slide on the sliding groove 1501 of the floating module of the supporting frame 1005 in the direction thereof, so as to prevent the floating module from rotating and facilitate the monitoring of the distance sensor. The support frame 1005 serves to connect the proximal frame 1001 and the distal frame 1002, and to restrain the floating module, thereby further simplifying the structure and reducing the mass.

With reference to fig. 4, 5 and 8, the pulley 4006 can slide on the upper roller track 1104 of the proximal frame 1001 and the roller track 1204 of the distal frame 1002, so as to reduce friction between the pulley module and the frame module while ensuring that the pulley module slides along a predetermined path, thereby ensuring smoothness and low delay of stiffness adjustment.

With reference to fig. 1, 2, 6, 7 and 8, the elastic pieces are arranged on four sides of a square, and the rails are designed at corresponding positions of the frame module 1, so that the space size of the whole variable-stiffness grinding and polishing device is reduced on the premise of uniform stress, and the space utilization rate is increased. Meanwhile, the tracks on the proximal frame 1001 and the distal frame 1002 are combined with the proximal rotating track 2001 and the distal rotating track 1003, so that the rotating motion of the stiffness adjusting motor is converted into the synchronous linear motion of the 4 sliding modules.

The function of the present invention will be generally described with reference to fig. 1-11. The invention is composed of a frame module 1, a rigidity adjusting motor module 2, a floating module 3, 4 pulley modules 4 which have the same structure and are distributed in an equal circumference by taking a central axis as a center, and a robot control part.

When the variable-rigidity grinding and polishing executing device is used, a power supply needs to be disconnected in an assembling and installing stage, and the power supply needs to be connected in a debugging and processing stage and exchanges information with a robot control system, and the method comprises the following steps:

(1) the proximal end frame 1001 and the stiffness adjusting motor module 2 in the frame module 1 are mounted to the end of the robot arm and fixed, and the distal end rotating rail is mounted on the rotating rail mounting block 1206 of the distal end frame 1002. And (3) after the floating module 3 is completely assembled, the elastic piece 3003 penetrates through the gaps of 2 pulleys 4004 in the pulley module 4, and all the rollers 4006 are arranged on the roller bracket 4005 to prepare for the step (2).

(2) The proximal shaft 4001 of the pulley module 4 sequentially passes through the proximal rotation rail 2001, the roller bracket 4005 and the upper slider rail 1103, and the distal shaft 4002 sequentially passes through the distal rotation rail 1003, the lower slider rail 1203 and the roller bracket 4005, and is fixed by nuts. The support frame 1005 is fixedly connected with the proximal end frame 1001 and the distal end frame 1003 through screws and nuts, and the sliding shaft 3202 on the connecting piece 3002 penetrates through the floating module sliding groove 1501 of the support frame 1005. Finally, the distance sensor 1004 is attached to the proximal frame 1001 by screws. After the variable-rigidity grinding and polishing actuator is installed, the whole variable-rigidity grinding and polishing actuator can be directly installed at the tail end of the mechanical arm without being disassembled.

(3) And (3) turning on power supplies of the distance sensor 1004 and the stiffness adjusting motor module 2, detecting and adjusting functions of feedback rigidity and type variables of the distance sensor, and transmitting the data into the robot control system.

(4) And setting a grinding track and required contact force according to the shape and the processing requirement of the workpiece to be processed. The former can be completed according to the self-contained functions of the robot control system, and the latter can be completed by adjusting the rigidity through the rigidity-variable grinding and polishing execution device and finely adjusting the joint track of the robot.

(5) And (4) turning on the grinding motor 4 to drive the mechanical arm to execute grinding and polishing operation. In the process, the rotating angle of the stiffness adjusting motor module 2 and the data of the rigidity and deformation quantity recorded by the distance sensor 1004 can be fed back to the robot control system, and can be analyzed and optimized by technicians.

(6) And after the grinding and polishing operation is finished, the power supply is turned off, and the variable-rigidity grinding and polishing executing device is taken down. Other actuators may be mounted on the arm for further processing.

The invention reserves the characteristics of low delay and high precision of the mechanical transmission variable stiffness device, and carries out a series of redesign and optimization on the arrangement of the variable stiffness element and the construction of a transmission system. The overall size and the mass of the variable-rigidity grinding and polishing executing device are reduced as much as possible, the strict quality requirement of the mechanical arm on the tail end executing mechanism can be met, and the negative influence of the executing device on the flexibility of the mechanical arm is reduced as much as possible. In addition, the invention also provides a variable-rigidity grinding and polishing execution method. In general, a new design idea is provided for the traditional mechanical transmission variable stiffness mode, so that the method has more competitive advantages.

Claims (9)

1. The utility model provides a become rigidity and grind and throw final controlling element which characterized in that: the steel adjusting mechanism comprises a frame module, a steel adjusting motor module, a floating module and a pulley module, wherein the frame module comprises a near-end frame and a far-end frame which are arranged at an upper and lower interval, the near-end frame and the far-end frame are supported and erected through a peripheral supporting frame, the upper end face of the near-end frame is connected and fixed with the tail end of a mechanical arm, a distance sensor is further arranged on the upper end face of the near-end frame, the steel adjusting motor module is arranged in the middle of the near-end frame, the floating module is arranged in the frame module and comprises a motor base used for installing a grinding motor, elastic sheets and sliding shafts are respectively arranged on the periphery of the motor base, the sliding shafts are respectively in guiding fit with sliding grooves of the floating modules on the peripheral supporting frame of the corresponding frame module, the elastic sheets are respectively supported and erected through the corresponding pulley module, and the steel adjusting motor module drives the pulley module to run through a transmission mechanism, the pulley module is driven to move along the direction of the sliding rod track of the frame module, and the relative distance between the elastic sheet connecting end and the supporting end of the floating module is changed, so that the function of changing rigidity is realized;

the pulley module is characterized in that a near-end shaft and a far-end shaft of the pulley module are respectively installed on a near-end rotating track and a far-end rotating track which are arranged above and below the pulley module in a guiding mode, the near-end rotating track is located below the steel adjusting motor module and connected with a planetary gear carrier of the steel adjusting motor module, the far-end rotating track is installed on a rotating track installation seat in a rotating mode, guide rods are distributed on the near-end rotating track and the far-end rotating track along the circumference by respectively using a middle fixed sleeve of the near-end rotating track and the far-end rotating track as the center, and guide grooves are respectively formed in the middle of the guide rods.

2. The variable stiffness polishing actuating device according to claim 1, wherein: the middle part of the near-end frame is provided with a steel adjusting motor preformed hole for installing a steel adjusting motor module, mounting preformed holes for connecting and fixing the tail end of the mechanical arm are distributed around the steel adjusting motor preformed hole, and the mounting preformed holes are distributed in an equal circumference mode by taking the central axis of the steel adjusting motor preformed hole as the center; the periphery of the lower end face of the near-end frame is distributed with upper sliding rod rails, upper roller rails and screw clearance holes for installing and fixing a support frame, the upper sliding rod rails and the upper roller rails are distributed in an equal circumference mode by taking the central axis of a preformed hole of the stiffness adjusting motor as the center, the upper roller rails are of a sinking groove structure, are positioned on the lower end face of the near-end frame, are arranged in parallel with the upper sliding rod rails and are positioned on two sides of the upper sliding rod rails; the middle part of distal end frame is equipped with the grinding motor preformed hole that is used for installing grinding motor, the grinding motor preformed hole outside is equipped with rotatory track mount pad, the distribution has down slide bar track, lower gyro wheel track and is used for installing the screw clearance hole of fixed stay frame under the distal end frame terminal surface all around, the gyro wheel track is heavy groove structure down, and it is located the lower terminal surface of distal end frame, sets up and is located the orbital both sides of down slide bar with the down slide bar track side by side.

3. The variable stiffness polishing actuating device according to claim 1, wherein: the support frame is of a [ shape structure, the upper end face and the lower end face of the support frame are respectively provided with a mounting and fixing hole for mounting and fixing the support frame on the near-end frame and the far-end frame, and the middle part of the support frame is provided with a floating module chute which is vertically arranged.

4. The variable stiffness grinding and polishing actuator according to claim 1, wherein: the rigidity adjusting motor module comprises a rigidity adjusting motor shell fixedly mounted on the bottom end face of the near-end frame, a planet wheel carrier is mounted in the rigidity adjusting motor shell, the gear transmission assembly is driven by a rigidity adjusting motor above the gear transmission assembly, and the outer side of the planet wheel carrier is connected with a near-end rotating track.

5. The variable stiffness grinding and polishing actuator according to claim 4, wherein: the gear transmission component comprises a planetary gear train formed by three planetary gears in a surrounding mode, the planetary gears are all installed on a planetary gear carrier, an inner gear ring is distributed on the inner side face of the shell of the stiffness adjusting motor and is in transmission engagement with the planetary gears, a sun gear is arranged on the planetary gear train, and the sun gear is installed at the output shaft end of the stiffness adjusting motor.

6. The variable stiffness polishing actuating device according to claim 1, wherein: the floating module comprises a motor base, the motor base is square, a polishing motor is installed on the bottom end face of the motor base, a polishing head is installed at the output shaft end of the polishing motor, connecting pieces which are uniformly distributed along the circumference direction of the central line and are fixed with elastic pieces which are uniformly distributed along the circumference direction of the central line and use the center of the motor base as the central line are fixedly installed around the motor base respectively, and sliding shafts for guiding are respectively arranged at the outer end parts of the connecting pieces.

7. The variable stiffness polishing actuating device according to claim 2, wherein: the pulley module including the pulley frame of vertical setting, rotate the pulley of installing two upper and lower intervals settings in the pulley frame respectively, pulley frame's last lower extreme is installed near end axle and distal end axle respectively, the guiding axle is installed respectively to the tip of near end axle and distal end axle, install the gyro wheel support on the guiding axle respectively, the gyro wheel support is including the axle sleeve with guiding axle sleeve fit, the gyro wheel axle is installed respectively to the both sides of axle sleeve, the gyro wheel is installed respectively to the tip of gyro wheel axle, the guiding axle of near end axle and the cooperation of the last slide bar track direction of near end frame, and the epaxial gyro wheel of near end and the cooperation of last gyro wheel track direction, the guiding axle of distal end axle and the cooperation of the lower slide bar track direction of distal end frame, and the epaxial gyro wheel of far end and the cooperation of lower gyro wheel track direction.

8. The variable stiffness grinding and polishing actuator according to claim 6, wherein: one end of the elastic sheet of the floating module is fixedly connected through the connecting sheet, the other end of the elastic sheet is supported through the pulleys corresponding to the pulley modules, and the relative distance between the connecting end and the supporting end of the elastic sheet is changed along with the movement of the pulley modules, so that the function of changing rigidity is realized.

9. The specific execution method of the variable-rigidity grinding and polishing execution device based on claim 1 is characterized by comprising the following specific steps of: (1) mounting a near-end frame and a rigidity-adjusting motor module in a frame module to the tail end of the mechanical arm and fixing, mounting a near-end rotating track below the near-end frame through a rigidity-adjusting motor shell, mounting a far-end rotating track on a rotating track mounting seat of a far-end frame, completely assembling a floating module, inversely mounting a grinding motor in a grinding motor preformed hole, extending an output shaft of the grinding motor out of the grinding motor preformed hole, mounting a grinding head, penetrating an elastic sheet through a gap between an upper pulley and a lower pulley in a pulley module, and mounting all rollers on a roller bracket to prepare for the step (2); (2) a near-end shaft of the pulley module sequentially penetrates through the near-end rotating track, the roller support and the upper sliding rod track, and a far-end shaft sequentially penetrates through the far-end rotating track, the lower sliding rod track and the roller support and is fixed by nuts; fixedly connecting a support frame with a near-end frame and a far-end frame through screws and nuts, and enabling a sliding shaft on a connecting sheet to penetrate through a floating module sliding groove of the support frame; finally, the distance sensor is fixedly connected to the near-end frame through a screw; after the variable-rigidity grinding and polishing actuator is installed, the whole variable-rigidity grinding and polishing actuator can be directly installed at the tail end of the mechanical arm without being disassembled; (3) turning on power supplies of the distance sensor and the stiffness adjusting motor module, detecting and adjusting functions of feedback stiffness and type variables of the distance sensor, and transmitting data into a robot control system; (4) setting a grinding track and required contact force according to the shape and the processing requirement of a workpiece to be processed, wherein the grinding track can be completed according to the self-carried function of a robot control system, and the grinding and polishing contact force can be completed by adjusting the rigidity of a variable-rigidity grinding and polishing executing device and finely adjusting the joint track of the robot; (5) turning on a grinding motor, driving a mechanical arm to execute grinding and polishing operation, and feeding back data of a rotating angle of a stiffness adjusting motor module and data of rigidity and deformation recorded by a distance sensor to a robot control system in the process, wherein the data can be analyzed and optimized by technicians; (6) and after the grinding and polishing operation is finished, the power supply is turned off, the variable-rigidity grinding and polishing executing device is taken down, and other executing devices can be arranged on the mechanical arm to perform the next processing procedure.

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