CN103737577B - A kind of Six-DOF industrial robot driven containing ball screw assembly, - Google Patents

Abstract

The invention relates to a six-degree-of-freedom industrial robot driven by a ball screw pair, which realizes the full circle rotation of the waist through the waist rotation mechanism, and realizes the two-dimensional translation by the two-degree-of-freedom parallel mechanism composed of the shoulder swing mechanism and the elbow rotation mechanism, respectively. The motor installed on the slewing platform drives the ball screw to drive; the three mutually orthogonal rotation axes connected by the forearm rotation mechanism, the wrist rotation mechanism and the tool holder rotation mechanism are independently driven by the three motors to realize the execution end. Three-degree-of-freedom attitude adjustment of the tool. The present invention not only maintains the advantage of the large working space of the series mechanism, but also adopts the ball screw drive, which not only ensures the rigidity of the mechanism, but also reduces the position of the driving motor, obtains better dynamic characteristics, has a large bearing capacity, and is easy to realize high-speed or Ultra-high-speed operation; it has the advantages of no backlash, high rigidity, easy to realize inching feed, small cumulative error, high motion precision, convenient solution of forward and reverse kinematics, and easy control.

Description

A six-degree-of-freedom industrial robot driven by a ball screw

technical field

The invention relates to the field of industrial automation, in particular to a six-degree-of-freedom industrial robot driven by a ball screw pair.

Background technique

Industrial automation is a technology that uses various parameters in industrial production as the control purpose to realize various process controls and minimize human operation in the entire industrial production. Industrial robots are an important aspect of industrial automation products. Industrial robots are machines that perform work automatically. They are machines that implement various functions by their own power and control capabilities. Industrial robots are multi-joint manipulators or multi- degrees of freedom robot. In the next few years, China may become the world's largest robot demand market. Due to the rapid development of modern computer technology and the continuous maturity of multi-axis motion control technology, the cost of industrial robots has gradually decreased, and has now entered a stage of explosive growth. The vast majority of industrial robots have six axes, three of which send the end-mounting tool to a space-accessible position, and the other three axes realize the spatial attitude adjustment of the end-end welding tool. Traditional articulated robots install the motors at the joints, making the robotic arm cumbersome, and have disadvantages such as large moment of inertia, poor stiffness, and large cumulative error. The dynamic performance of the mechanism is poor, and it is difficult to meet the increasingly high-speed and high-precision requirements. The series mechanism has better kinematic performance in terms of mechanism design, but the dynamic performance is lower; compared with the series robot, the parallel mechanism has no cumulative error and high precision, and the driving device can be placed on or close to the fixed platform. The position of the moving part is light, the speed is high, the dynamic response is good, the structure is compact, the rigidity is high, and the carrying capacity is large. The space is often small, and it is difficult to apply to fields that require a large working space. Moreover, the robot whose drive motors are all installed at the joints has a high failure rate and poor reliability, which is easy to cause large joint errors and has a great impact on the accuracy of the robot. Due to these many shortcomings, it is difficult to take into account the flexibility of the existing robot structure And high-precision characteristics, it is difficult to meet the operation requirements of large working space, high precision, and high reliability, which has become a difficult problem in the design and manufacture of high-end industrial robots.

Contents of the invention

The purpose of the present invention is to overcome the problems existing in the prior art, to provide a robot mechanism of a series-parallel mechanism, which integrates the respective advantages of the series mechanism and the parallel mechanism, and under the premise of ensuring the flexibility, high precision and high reliability of the robot, Place the motor on the base as much as possible or arrange the motor reasonably, give full play to the advantages of the series-parallel mechanism, greatly improve the reliability of the robot, reduce maintenance costs, improve the stability of the robot's operation, and achieve better dynamic performance of the robot.

The present invention realizes the above object through the following technical solutions:

A six-degree-of-freedom industrial robot driven by a ball screw pair, including a waist rotation mechanism, a shoulder swing mechanism, an elbow rotation mechanism, a forearm rotation mechanism, a wrist rotation mechanism, a tool holder rotation mechanism, a machine base, and a rotary platform;

The waist slewing mechanism is installed on the machine base by the sixteenth revolving pair through the slewing platform, and the sixteenth revolving pair is driven by the first servo motor to realize the full circle rotation of the waist;

The shoulder swing mechanism includes a rotary platform, a first ball screw, a first ball screw sleeve, a first connecting rod, a second connecting rod and a third connecting rod, the first ball screw and the rotary platform are rotated by the first Auxiliary connection, the first ball screw and the first ball screw sleeve are connected by the first screw pair, the first connecting rod and the first ball screw sleeve are connected by the eleventh rotating pair, the first connecting rod and the rotary platform It is connected by the third rotating pair, the first connecting rod and the second connecting rod are connected by the tenth rotating pair, the third connecting rod and the slewing platform are connected by the fourth rotating pair, and the second connecting rod and the third connecting rod are connected by the ninth rotating pair. Secondary connection, the first ball screw is driven by the second servo motor;

The toggle mechanism includes a second ball screw, a second ball screw sleeve, a fourth connecting rod, a fifth connecting rod and a sixth connecting rod, the second ball screw is connected to the rotary platform by a second rotating pair, The second ball screw and the second ball screw sleeve are connected by the second screw pair, the fourth connecting rod and the second ball screw sleeve are connected by the twelfth rotating pair, the fourth connecting rod and the rotary platform are connected by the fifth The fourth connecting rod and the fifth connecting rod are connected by the sixth rotating pair, the fifth connecting rod and the sixth connecting rod are connected by the seventh rotating pair, and the third connecting rod and the sixth connecting rod are connected by the eighth rotating pair connection; the second ball screw is driven by the third servo motor;

The forearm rotation mechanism, the wrist rotation mechanism and the tool holder rotation mechanism form a three-dimensional rotation mechanism. The forearm rotation mechanism is connected by the forearm and the sixth connecting rod through the thirteenth rotating pair, and is connected by the fourth servo motor mounted on the sixth connecting rod. Driven by a motor, the wrist rotation mechanism is connected by the forearm and the wrist through the fourteenth rotation pair, driven by the fifth servo motor installed on the forearm, and the tool holder rotation mechanism is connected by the wrist and the end tool holder through the fifteenth rotation pair, Driven by a sixth servo motor mounted on the wrist.

The sixteenth turning pair is perpendicular to the base; the first turning pair, the second turning pair, the third turning pair, the fourth turning pair, the fifth turning pair, the sixth turning pair, the seventh turning pair, the eighth turning pair The turning pairs, the ninth turning pair, the tenth turning pair and the fourteenth turning pair are parallel to each other, the fourth turning pair is coaxial with the fifth turning pair; the eleventh turning pair is coaxial with the tenth turning pair, and the twelfth turning pair is coaxial The turning pair is coaxial with the sixth turning pair, the thirteenth turning pair is perpendicular to the fourteenth turning pair, and the fourteenth turning pair is perpendicular to the fifteenth turning pair.

In the present invention, the whole rotation of the waist is driven by the motor on the slewing platform, and the two-degree-of-freedom parallel mechanism composed of the shoulder swing mechanism and the elbow slewing mechanism realizes two-dimensional translation, which are respectively driven by the ball screw driven by the motor installed on the slewing platform; The three mutually orthogonal rotation axes connected by the forearm rotation mechanism, the wrist rotation mechanism and the tool holder rotation mechanism are independently driven by three motors to realize the three-degree-of-freedom attitude adjustment of the end tool. Compared with the prior art, it has the following outstanding advantages:

1. The series-parallel mechanism is adopted, which has the advantages of small cumulative error, high rigidity and large working space of the series mechanism, and the driving device is placed on the machine base as much as possible;

2. In particular, the ball screw transmission scheme is used to minimize the position of the drive motor, which reduces the load on the arm rod and the moment of inertia of the whole machine. The transmission is stable, with no backlash, high precision and high rigidity. And it has good dynamic performance, which reduces the load capacity of the motor shaft and is conducive to the improvement of precision;

3. Reasonably arrange the driving device of the mechanism, improve the balance performance of the overall mechanism, and further improve the dynamic performance of the mechanism;

4. The structure is simple, which is convenient for the solution of forward and reverse kinematics, trajectory planning, error compensation, and convenient and precise control. In addition, different devices installed at the end can realize different industrial uses, such as palletizing, cutting, assembling, spraying, welding and handling, etc.

Description of drawings

FIG. 1 is a structural schematic diagram of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 2 is a schematic diagram of the shoulder swing mechanism of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 3 is a schematic diagram of the elbow rotation mechanism of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 4 is a schematic diagram of a forearm twisting mechanism, a wrist turning mechanism and a tool holder turning mechanism of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 5 is a schematic diagram of the first working state of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 6 is a schematic diagram of the second working state of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 7 is a schematic diagram of a third working state of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Fig. 8 is a schematic diagram of the fourth working state of the six-degree-of-freedom industrial robot driven by a ball screw pair.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Referring to Figures 1, 2, 3 and 4, a six-degree-of-freedom industrial robot driven by a ball screw consists of a machine base, a rotary platform, a waist rotary mechanism, a shoulder swing mechanism, an elbow rotary mechanism, a forearm rotary mechanism, and a wrist rotary mechanism. It is composed of tool holder rotary mechanism. The rotary platform 16 is installed on the machine base 1 to realize the six-degree-of-freedom movement of the whole mechanism.

Referring to Fig. 1, the waist slewing mechanism is connected to the machine base 1 by the 16th revolving pair through the slewing platform 16, and is driven by the first servo motor to realize the full circle slewing motion.

1 and 2, the shoulder swing mechanism and the elbow rotation mechanism form a position adjustment mechanism. The shoulder swing mechanism shown in FIG. 2 is formed by connecting the rotary platform 16 , the first ball screw 4 , the first ball screw sleeve 5 , the first connecting rod 3 , the second connecting rod 7 and the third connecting rod 9 . The first ball screw 4 is rigidly connected to the second servo motor, the second servo motor is connected to the rotary platform 16 by the first rotary pair 18, the first ball screw 4 and the first ball screw sleeve 5 are connected by the first screw pair 21 connection, the first connecting rod 3 and the first ball screw sleeve 5 are connected by the eleventh rotating pair 23, the first connecting rod 3 and the rotary platform 16 are connected by the third rotating pair 19, the first connecting rod 3 and the second The second connecting rod 7 is connected by the tenth rotating pair 24 , the third connecting rod 9 is connected with the slewing platform 16 by the fourth rotating pair 20 , and the second connecting rod 7 and the third connecting rod 9 are connected by the ninth rotating pair 28 .

1 and 3, the toggle mechanism is composed of the second ball screw 2, the second ball screw sleeve 6, the fourth connecting rod 8, the fifth connecting rod 10, and the sixth connecting rod 12. Wherein, the second ball screw 2 is rigidly connected with the third servo motor, the third servo motor is connected with the rotary platform 16 by the second rotating pair 17, the second ball screw 2 and the second ball screw sleeve 6 are connected by the second The screw pair 22 is connected, the fourth connecting rod 8 is connected with the second ball screw sleeve 6 by the twelfth rotating pair 26, the fourth connecting rod 8 is connected with the rotary platform 16 by the fifth rotating pair 27, the fourth connecting rod 8 The fifth connecting rod 10 is connected by the sixth rotating pair 25, the fifth connecting rod 10 and the sixth connecting rod 12 are connected by the seventh rotating pair 30, the third connecting rod 9 and the sixth connecting rod 12 are connected by the eighth rotating pair 29 connect.

1 and 4, the forearm rotation mechanism includes the forearm 13, the forearm 13 is connected with the sixth connecting rod 12 through the thirteenth rotating pair 31, driven by the fourth servo motor 11, the fourth servo motor is installed on the sixth connecting rod 12 The front end is conducive to balancing the load on the front end of the forearm 13 to ensure good dynamic performance; the wrist rotation mechanism includes the wrist 14, which is connected to the forearm 13 through the fourteenth rotating pair 32, and is driven by the fifth servo motor to rotate The rotary mechanism of the tool holder includes the end tool holder 15, which is connected with the wrist 14 through the fifteenth rotating pair 33 and driven by the sixth servo motor. The fourth servo motor, the fifth servo motor and the sixth servo motor are independently driven to realize three-dimensional rotation, thereby realizing tool attitude adjustment.

Referring to Figures 1, 5, 6, 7, and 8, the industrial robot realizes the two-dimensional translation of the plane through the mechanism composed of the shoulder swing mechanism and the elbow rotation mechanism, and delivers the tool holder of the forearm execution end to the predetermined area; The full circle rotation of the rotating platform realizes the position adjustment of the execution end within the spatial range and obtains a larger working space; the three-dimensional rotation of the forearm rotation mechanism, the wrist rotation mechanism and the tool holder rotation mechanism realizes the adjustment of the tool attitude; the use of sideless Clearance ball screw pair transmission, easy to achieve high-speed operation and micro-feeding. The above mechanism characteristics realize various positions and postures of the mechanism as shown in Figure 5-Figure 8, flexibly and simply send tools to work at different points in space, and obtain better dynamic performance, achieve high precision, high reliability, Excellent characteristics of running stability and easy maintenance.

Claims (2)

1., containing the Six-DOF industrial robot that ball screw assembly, drives, comprise waist slew gear, shoulder swing mechanism, elbow slew gear, forearm rotating mechanism, wrist slew gear, instrument deck slew gear, support and revolving dial; It is characterized in that:

Described waist slew gear is arranged on support by revolving dial by the 16 revolute pair, and the 16 revolute pair, by the first driven by servomotor, realizes waist circumferential rotation type;

Described shoulder swing mechanism comprises revolving dial, first ball-screw, first ball-screw sleeve, first connecting rod, second connecting rod and third connecting rod, first ball-screw is connected by the first revolute pair with revolving dial, first ball-screw is connected by the first screw pair with the first ball-screw sleeve, first connecting rod is connected by the 11 revolute pair with the first ball-screw sleeve, first connecting rod is connected by the 3rd revolute pair with revolving dial, first connecting rod is connected by the tenth revolute pair with second connecting rod, third connecting rod is connected by the 4th revolute pair with revolving dial, second connecting rod is connected by the 9th revolute pair with third connecting rod, first ball-screw is by the second driven by servomotor,

Described elbow slew gear comprises the second ball-screw, second ball-screw sleeve, double leval jib, 5th connecting rod and six-bar linkage, second ball-screw is connected by the second revolute pair with revolving dial, second ball-screw is connected by the second screw pair with the second ball-screw sleeve, double leval jib is connected by the 12 revolute pair with the second ball-screw sleeve, double leval jib is connected by the 5th revolute pair with revolving dial, double leval jib is connected by the 6th revolute pair with the 5th connecting rod, 5th connecting rod is connected by the 7th revolute pair with six-bar linkage, third connecting rod is connected by the 8th revolute pair with six-bar linkage, second ball-screw is by the 3rd driven by servomotor,

Described forearm rotating mechanism, wrist slew gear and instrument deck slew gear composition three-dimensional revolving gear, forearm rotating mechanism is connected by the 13 revolute pair with six-bar linkage by forearm, by the 4th driven by servomotor be arranged on six-bar linkage, wrist slew gear is connected by the 14 revolute pair with wrist by forearm, by the 5th driven by servomotor be arranged on forearm, instrument deck slew gear is connected by the 15 revolute pair with end-of-arm tooling deck by wrist, by the 6th driven by servomotor be arranged in wrist.

2. industrial robot according to claim 1, is characterized in that: the 16 described revolute pair is perpendicular to support; First revolute pair, the second revolute pair, the 3rd revolute pair, the 4th revolute pair, the 5th revolute pair, the 6th revolute pair, the 7th revolute pair, the 8th revolute pair, the 9th revolute pair, the tenth revolute pair and the 14 revolute pair are parallel to each other, and wherein the 4th revolute pair is coaxial with the 5th revolute pair; 11 revolute pair is coaxial with the tenth revolute pair, and the 12 revolute pair is coaxial with the 6th revolute pair, and the 13 revolute pair is mutually vertical with the 14 revolute pair, and the 14 revolute pair is mutually vertical with the 15 revolute pair.