Background
A cooperative robot is a robot capable of interacting with a person in a shared space or working safely at a close distance from the person, and is distinguished from a conventional industrial robot mainly in three aspects of safety, interactivity, and ease of use. The cooperative robot is mainly characterized in safety by a collision detection function, so that the damage to people can be prevented; the interactive characteristic is light, easy to install, it is easy to interact with people; and in the aspect of easiness, the teaching programming of the cooperative robot is convenient and the cooperative robot is easy to use.
Most of the cooperative robots in the market at present are single-mechanical-arm cooperative robots, that is, only one cooperative mechanical arm is included in one cooperative robot system. Compared with a single-arm cooperative robot, the double-arm cooperative robot is more human-like, can realize more complex functions through the cooperation between the double arms, and has higher scientific research and practical value.
In existing robots, typically represented as Baxter, YuMi, etc., each consists of two seven-axis single robot arms. Generally, the hardware cost of the seven-axis mechanical arm is high, the time required for manufacturing is long, and the labor cost is high; meanwhile, the seven-shaft single arm is heavy in mechanical structure; therefore, the seven-axis double-arm cooperative robot is heavy in standard weight and low in load; the structural weight of the seven-axis mechanical arm is large, so that the rotational inertia of the joint is large; the seven-axis mechanical arm is complex in shape, and multi-axis linkage is needed during movement, so that the movement acceleration is low; in addition, for the seven-axis double-arm cooperative robot, the joint moment load is high, the kinematic model is complex, and the collision detection based on current monitoring is not facilitated. If a force sensor is added, the cost of the robot arm tends to increase.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a simple structure, simple double-arm cooperation robot of joint linkage.
The utility model provides a both arms cooperative robot, it includes:
a base;
the upright post is arranged on the base along the vertical direction;
the pair of vertical adjusting mechanisms are respectively arranged on the stand columns;
the mechanical arms are assembled on a vertical adjusting mechanism respectively, the vertical adjusting mechanism is used for adjusting the height positions of the corresponding mechanical arms, and each mechanical arm is provided with at least two movable joints with axially parallel rotating shafts.
Wherein, set up linear guide mounting base on the stand, each vertical adjustment mechanism includes a linear guide base, ball, slip table and servo motor, set up one respectively on two different sides of linear guide mounting base linear guide base, linear guide mounting base, linear guide base and ball all set up along vertical direction, slip table cover locate on the ball and slide set up in on the linear guide base, servo motor is used for driving ball and then adjusts the position of slip table in vertical direction.
The linear guide rail bases of the pair of vertical adjusting mechanisms are respectively arranged on two vertical side surfaces of the linear guide rail mounting base.
Wherein, the arm includes first joint subassembly, first connecting rod, second joint subassembly and second connecting rod, first joint subassembly is connected to the slip table, the one end of first connecting rod is articulated extremely first joint subassembly, the second joint subassembly set up in the other end of first connecting rod, the one end of second connecting rod is articulated extremely the second joint subassembly.
The first joint assembly comprises a connecting flange, a first joint base and a first rotating joint, the connecting flange is used for connecting the first joint base to the sliding table, and the first rotating joint is rotatably arranged on the first joint base.
Wherein the rotating shaft of the first rotating joint is a vertical shaft.
The second joint assembly comprises a second rotating joint, and a rotating shaft of the second rotating joint is a vertical shaft.
The mechanical arm further comprises a third joint assembly, the third joint assembly is arranged at the other end of the second connecting rod, the third joint assembly comprises a third rotating joint, and a rotating shaft of the third rotating joint is a vertical shaft.
Wherein, first, second, third rotation joint all contain motor, motor mounting flange, reduction gear mounting flange, rotation joint shell, joint torque output flange and the harmonic reduction gear of taking the encoder, the motor of taking the encoder passes through motor mounting flange to be fixed, and the output shaft and the harmonic reduction gear input of motor link firmly, and reduction gear mounting flange links firmly with motor mounting flange and link mechanism respectively, and the harmonic reduction gear output links firmly with joint torque output flange.
Compared with the prior art, the double-arm cooperative robot has the advantages that the hardware cost is greatly reduced, the time required by manufacturing is reduced, the labor cost is reduced, the load larger than that of a seven-axis single mechanical arm can be realized by lighter weight, and the practicability is higher; further, because the mechanical arm of this application has two at least pivot axial direction parallel's freely movable joint, consequently this application mechanical arm is the arm of many joint shapes in plane, and mechanical structure is simple relatively, and plane joint's inertia of rotation is little, and the joint linkage is comparatively simple during the motion because can reach very high motion acceleration.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by the ordinary skilled person in the art without creative work belong to the protection scope of the present invention.
Referring to fig. 1, the dual-arm cooperative robot according to a preferred embodiment of the present invention includes a base 1, a column 2, a pair of vertical adjustment mechanisms (not shown), and a pair of arms 3.
The base 1 provides support for the upright 2, the vertical adjustment structure and the robotic arm 3. In this application, base 1 is the box structure that horizontal dimension is greater than stand 2. For the purpose of controlling the robot arm 3 and the vertical adjustment mechanism, a voltage converter and a robot controller may be integrated in the base 1. In other embodiments, the voltage converter and the robot controller may be external.
In other embodiments, a plurality of moving wheels controlled by electromagnetic means can be disposed on the bottom of the base 1 to achieve better human-computer interaction effect.
The upright column 2 is arranged on the base 1 along the vertical direction. The vertical direction is the height direction in the general sense.
A pair of vertical adjustment mechanisms are arranged in parallel on the upright post 2. Specifically, referring to fig. 2 and fig. 3 together, in the embodiment, the upright 2 is provided with a linear guide mounting base 201 and a lifting shaft housing 206, the linear guide mounting base 201 provides two side surfaces for connecting the vertical adjusting mechanism, the linear guide mounting base 201 is located in the lifting shaft housing 206, and the two side surfaces for connecting the vertical adjusting mechanism are exposed from an opening of the lifting shaft housing. Each vertical adjustment mechanism includes a linear guide rail base 202, a roller screw 203, a slide table 204, and a servo motor 205. A linear guide rail base 202 is respectively arranged on the two side surfaces for connecting the vertical adjusting mechanism, and is used for providing a sliding guide groove in the vertical direction. Linear guide rail mounting base 201, linear guide rail base 202 and ball 203 all set up along vertical direction, and the slip table 204 cover locate on ball 203 and slide set up in on the linear guide rail base 202, servo motor 205 is used for driving ball and then adjusts the ascending position of slip table in vertical direction.
Preferably, the linear guide bases 202 of the pair of vertical adjustment mechanisms are respectively disposed on both vertical sides of the linear guide mounting base 201. In other embodiments, the included angle between the two sides of the linear guide mounting base 201 for connecting to the vertical adjustment mechanism may be any other angle.
Each vertical adjustment mechanism may be equipped with an encoder and a motor drive controller in addition to the servo motor 205. An output shaft of the servo motor 205 is connected with the ball screw 203 through a coupler, and when the servo motor works, the sliding table 204 and the mechanical arm 3 fixedly connected with the sliding table move in the vertical direction relative to the base 1. A power cable and a communication cable led out from the base 1 are connected to the joint of the vertical adjusting mechanism and the mechanical arm 3 through a drag chain mechanism and then enter the mechanical arm 3.
In other embodiments, the vertical adjustment mechanism may also be implemented by combining a linear module with a synchronous belt with a brushless motor or a synchronous motor or a stepping motor with a speed reducer.
The mechanical arm includes a first joint assembly, a first link, a second joint assembly, a second link 309, and a third joint assembly. The first joint assembly is connected to the sliding table 204, one end of the first connecting rod is hinged to the first joint assembly, the second joint assembly is arranged at the other end of the first connecting rod, one end of the second connecting rod is hinged to the second joint assembly, and the third joint assembly is arranged at the other end of the second connecting rod.
Specifically, referring to fig. 4 to 6 together, the first joint component includes a connecting flange 301, a first joint base 302, a first joint upper shell 304, a first joint lower shell 303 and a first rotating joint 305. Preferably, the axis of rotation of the first revolute joint 305 is a vertical axis. The connecting flange 301 is fixedly connected to the sliding table 204, and is used for connecting the first joint base 302 to the sliding table 204. Specifically, the first joint base 302 is fastened to the attachment flange 301 by screws. The first rotating joint 305 is rotatably disposed on the first joint base 302, and the first joint upper shell 304 and the first joint lower shell 303 are used for sealing the top surface and the bottom surface of the first joint base 302, respectively. The first link includes a first link base 306 and a first link upper housing 307. The motor end of the first rotating joint 305 is fixedly connected to the first joint base 302, and the torque output end is fixedly connected to the first link base 306 upwards, so that the first link can perform plane rotation movement relative to the first joint assembly.
The second joint assembly includes a second revolute joint 308 and a second joint housing 310; preferably, the rotating shaft of the second rotating joint 308 is a vertical shaft, and the second joint housing 310 is fixedly connected to the second connecting rod 309. In this embodiment, the torque output end of the second rotating joint 308 is connected to the first link base 306, and the motor end is connected to the second link 309, so that the second link 309 can perform a planar rotation motion relative to the first link.
The third joint assembly includes a third rotational joint 311 and a third joint housing 312. Preferably, the rotating shaft of the third rotating joint 311 is a vertical shaft. The third joint housing 312 is fixedly connected to the second connecting rod 309, a motor end flange of the third rotating joint 311 is fixedly connected to the second connecting rod 309, and a torque output end flange is horizontally downward.
Referring to fig. 7, the third rotating joint 311 includes a motor 321 with an encoder, a motor mounting flange 322, a speed reducer mounting flange 323, a rotating joint housing 324, a joint torque output flange 325, and a harmonic speed reducer, where the motor 321 is fixed by the motor mounting flange 322, an output shaft of the motor 321 is fixedly connected to an input end of the harmonic speed reducer, the speed reducer mounting flange 323 is fixedly connected to the second connecting rod 309, the motor mounting flange 311, and the connecting rod mechanism by screws, and an output end of the harmonic speed reducer is fixedly connected to the joint torque output flange 325. The harmonic reducer comprises a harmonic reducer wave generator 331, a harmonic reducer bearing 332, a harmonic reducer output 333, and the like. When the output shaft of the motor rotates, the harmonic reducer wave generator 331 rotates along with the output shaft, and drives the steel wheel and the flexible wheel to be meshed in a wave form. After the motor torque is amplified by the harmonic reducer, the motor torque is output through the output end 333 of the harmonic reducer and the joint torque output flange 325.
Preferably, the first revolute joint 305 and the second revolute joint 308 are identical in structure to the third revolute joint.
In other embodiments, the harmonic reducer may be replaced by a planetary gear reducer or a synchronous belt/wheel reduction structure. Alternatively, instead of the reduction mechanism, the output shaft of the motor may directly drive the connecting rod, instead of the above embodiment.
The power supply and the communication interface are arranged at the first joint component, and the power supply and the communication cable led out from the vertical adjusting mechanism are electrically connected with the first joint component through the corresponding interface in the first joint component. The first joint component and the second joint component are electrically connected through a power supply and a communication cable of the first connecting rod; the second joint assembly and the third joint assembly are electrically connected to each other via a power supply and a communication cable of the second link 309.
In this embodiment, the first, second, and third rotational joints 305, 308, and 311 of the robot arm all include a motor, an encoder, a harmonic reducer, and a motor drive controller, and the robot controller provided in the base 1 controls each rotational joint through a communication cable.
The pair of mechanical arms are symmetrically arranged and have the same structure, and the mechanical arms can respectively move independently or cooperatively.
Compared with the technical scheme of the existing seven-shaft single-arm robot, the joint number of the robot is small in cooperation with the two arms, parts such as structural members, motors, speed reducers and drivers of other joints are omitted, and the weight of the robot is greatly reduced. In addition, because the arm of this application has two at least pivot axial direction parallel's freely movable joint, consequently this application arm is the arm of many joint forms in plane, and the gravity of load is undertaken by mechanical structure and vertical axis for its atress mode is simple reasonable, and consequently, the load capacity also obtains promoting greatly. Further, in the application, since the horizontal joint motor does not need to bear a vertical load, the torque of the horizontal joint motor can be efficiently converted into the rotation angular velocity of each connecting rod, so that the robot has the characteristic of large horizontal acceleration of the tail end, and the robot can run at a high tail end velocity. And, because the mechanical model of the horizontal multi-joint structure mechanical arm is simple and clear, the collision detection of the robot based on current is sensitive, and the cost of a joint torque sensor is saved; the application has the advantages of simple and efficient mechanical design, and can realize collision detection without a torque sensor, thereby effectively reducing the cost. In addition, the horizontal joint of the single arm in the double-arm cooperative robot adopts a modular design, so that the joint is convenient to replace when reaching the design life or having a fault, and the maintenance cost is low. To sum up, this application both arms cooperative robot has single armed simple structure, the dead weight is little, load capacity is strong, joint modular design, do not need torque sensor can realize characteristics such as collision detection, easily realizes low-cost solution.
The above-described embodiments are merely illustrative of one or more embodiments of the present invention, and the description thereof is more specific and detailed, but not intended to limit the scope of the invention. It should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the spirit of the invention, and these are all within the scope of the invention. Therefore, the protection scope of the present invention should be subject to the appended claims.