CN111843989A - Robot wrist unit driven by hydraulic actuator - Google Patents
Robot wrist unit driven by hydraulic actuator Download PDFInfo
- Publication number
- CN111843989A CN111843989A CN202010562662.3A CN202010562662A CN111843989A CN 111843989 A CN111843989 A CN 111843989A CN 202010562662 A CN202010562662 A CN 202010562662A CN 111843989 A CN111843989 A CN 111843989A
- Authority
- CN
- China
- Prior art keywords
- pitching
- wrist
- hydraulic
- connecting plate
- angle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 210000000707 wrist Anatomy 0.000 title claims abstract description 117
- 230000005540 biological transmission Effects 0.000 claims abstract description 74
- 230000033001 locomotion Effects 0.000 claims abstract description 64
- 230000007246 mechanism Effects 0.000 claims description 17
- 230000009471 action Effects 0.000 claims description 15
- 230000008859 change Effects 0.000 claims description 6
- 230000003044 adaptive effect Effects 0.000 claims description 2
- 230000008878 coupling Effects 0.000 abstract description 8
- 238000010168 coupling process Methods 0.000 abstract description 8
- 238000005859 coupling reaction Methods 0.000 abstract description 8
- 230000010354 integration Effects 0.000 abstract description 5
- 239000012636 effector Substances 0.000 description 5
- 241000282414 Homo sapiens Species 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000009191 jumping Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J17/00—Joints
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/0009—Constructional details, e.g. manipulator supports, bases
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J9/00—Programme-controlled manipulators
- B25J9/10—Programme-controlled manipulators characterised by positioning means for manipulator elements
- B25J9/14—Programme-controlled manipulators characterised by positioning means for manipulator elements fluid
Landscapes
- Engineering & Computer Science (AREA)
- Robotics (AREA)
- Mechanical Engineering (AREA)
- Manipulator (AREA)
Abstract
The invention belongs to the technical field of robots, and particularly relates to a robot wrist unit driven by a motion decoupling hydraulic actuator, which solves the problems of complex mechanical structure and low integration level of a wrist due to the fact that a middle transmission link exists in the transmission chain length, realizes the motion decoupling of the wrist, greatly improves the flexibility, posture adjustment capacity and accurate positioning capacity of an end actuator, and comprises a hydraulic motor, a hydraulic swing cylinder, an angle sensor, a machine base, a connecting rib plate, a pitching circular ring, a side swinging end cover, a bearing, a ball cage type constant velocity universal joint, a coupling and an end flange connecting piece. The pitching axis, the side-swinging axis and the rotation axis of the wrist of the invention intersect at a point in space to form the spherical wrist, so that the decoupling of three active input motions of pitching, side-swinging and autorotation can be realized, the control of the wrist pose is simple and easy, the control precision is high, and the mechanical arm shake phenomenon caused by the motion coupling during the joint matching adjustment is effectively avoided.
Description
Technical Field
The invention belongs to the technical field of robot wrists, and particularly relates to a robot wrist unit driven by a motion decoupling hydraulic actuator.
Background
In the current society of high-speed development, robots are entering industries such as light industry, heavy industry, medical treatment, military, aviation and the like on a large scale, and replace human beings to finish operations such as material conveying, assembly, classification, environmental survey, object accurate positioning and measurement, light or micro-processing and the like, so that the labor intensity is effectively reduced, the labor efficiency is improved, the labor time is prolonged, and even the working condition which can not be processed by human beings due to various reasons is finished. In response to this demand, a wide variety of industrial robots have been developed, which have in common the need for a flexible wrist mechanism to move an end effector in order to effectively replace a human being to perform a specific task.
The wrist of the robot is an important basic component of a connecting arm and a hand, and the performance of the wrist directly influences the positioning precision, flexibility and operation capacity of the end effector of the robot. Six degrees of freedom are required to realize accurate control of any position and posture of the robot end effector, and the wrist has three degrees of freedom. The wrist is located at the front end of the arm, and the weight of the wrist can generate additional load to the arm, thereby increasing the energy consumption and the instability of the movement. Therefore, the developed wrist has the advantages of small shape, compact structure, strong posture capability, miniaturization, high integration level and the like.
The traditional three-free wrist, such as a Pitch-yaw-roll wrist, has a complex structure, internal components are easy to generate motion interference, the manufacturing and the assembly are difficult, and the practicability is not strong; for example, the wrist based on the transmission of the spherical gear is formed by connecting a series of universal coupling joints and the spherical gear in series, although the structure is compact, the appearance is neat, and the three-degree-of-freedom motion can be realized, the manufacturing difficulty of the spherical gear is extremely high, the principle transmission error exists, and the practical application is extremely few; further, as for the wrist based on the parallel mechanism, the wrist has all the disadvantages of the parallel mechanism, such as poor posture capability, small accessible space/machine space ratio, complicated control technique, etc.
Mainstream motor + gear pair transmission or three free wrists of belt drive, like patent CN102029614A proposes a space robot wrist that utilizes universal joint and two hemispheres to realize the motion of three degrees of freedom of wrist, because the transmission of motion is realized through the transmission of motor + gear pair, have middle transmission link, the transmission chain length, so mechanical structure is complicated and not compact, receives the operating mode environment restriction serious simultaneously.
The novel hydraulic driving three-freedom wrist, as proposed in patent CN110027010A, is a hydraulic direct-drive spherical wrist which realizes three-freedom-degree movement of the wrist by means of three hydraulic swing cylinders, and although there is no intermediate transmission link to simplify the mechanical structure and make the wrist more compact, the self weights of the pitch and yaw movement links act on the output shaft of the rotation link mechanism, so that the rotation link bears a larger additional load and the system energy consumption and movement instability are increased; and then like patent CN110171015A put forward a hydraulic drive ball type wrist which utilizes a hydraulic motor and two hydraulic cylinders to realize wrist rotation, pitch and yaw movements, the influence of the mechanism self-weight of the pitch and yaw movement links on the rotation link output is solved, the energy consumption loss of the system is greatly reduced, and the stability of the wrist movement is also improved, but the rotary movement of the pitch and yaw movement links is formed by converting the linear movement of the hydraulic cylinders through the position relation between the mechanisms, the nonlinear conversion relation of linear displacement and speed to the rotary angle and angular speed exists, in addition, the restriction of the mechanism is received, the movement space is limited, the movement angle of the pitch and yaw is limited, and the flexibility and the posture adjustment capability of the end effector are severely limited.
Disclosure of Invention
Aiming at the problems of the traditional three-freedom wrist, the mainstream motor and gear pair transmission or belt transmission three-freedom wrist and the novel hydraulic drive three-freedom wrist, the invention provides the three-freedom spherical robot wrist unit driven by the hydraulic actuator with compact structure, high integration level, strong pose capability and motion decoupling, effectively solves the problems of complicated mechanical structure and low integration level of the wrist unit due to the existence of an intermediate transmission link in the transmission chain length, simultaneously realizes the motion decoupling of the wrist, greatly improves the flexibility, the posture adjustment capability and the accurate positioning capability of the end effector, and in addition, effectively solves the problem of limited pitching and side swinging angles of the wrist and greatly increases the achievable range of the pitching and side swinging angles.
The invention adopts the following specific technical scheme: a robot wrist unit driven by a hydraulic actuator comprises a hydraulic motor, a first connecting plate, a base, a ball cage type constant velocity universal joint, a pitching hydraulic swing cylinder, a pitching circular ring, a pitching angle sensor, a third connecting plate, a side swing end cover, a tail end flange connecting piece, a fourth connecting plate, a side swing angle sensor, a side swing hydraulic swing cylinder, a second connecting plate, a coupler, a self-rotation angle encoder, a bearing, connecting screws, fastening screws and keys, wherein the hydraulic motor is connected with the first connecting plate through the first connecting plate; the ball-cage type constant velocity universal joint is composed of a second transmission shaft, a star-shaped sleeve, a retainer, steel balls and a first transmission shaft.
The bottom of the machine base is provided with a cylindrical groove for placing a hydraulic motor, the middle of the machine base is provided with a round hole for extending a motor shaft, the four corners are processed with round corners and are simultaneously provided with four round holes, so that the wrist and the big arm or the small arm of the robot can be conveniently and fixedly connected through a bolt group, and the machine base is further provided with a threaded hole fixedly connected with the first connecting plate, the second connecting plate, the hydraulic motor shell and the self-rotation angle encoder shell; a shell of the hydraulic motor is fixedly connected in a cylindrical groove at the bottom of the base through a connecting screw, an output shaft of the hydraulic motor is rotatably connected with the base, and the first connecting plate and the second connecting plate are fixedly connected on the upper surface of the base through the connecting screw; the shell of the self-rotation angle encoder is fixedly connected with the base through a connecting screw, a rotating shaft of the self-rotation angle encoder is fixedly connected with an output shaft of the hydraulic motor through a fastening screw, and meanwhile, the output shaft of the motor is fixedly connected with a first transmission shaft of the ball-cage constant velocity universal joint through a coupling; the cylinder body of the pitching hydraulic swing cylinder is fixedly connected with the first connecting plate through a connecting screw, and the rotating shaft of the pitching hydraulic swing cylinder is fixedly connected with the pitching circular ring through a connecting screw; the shell of the pitching angle sensor is fixedly connected with the second connecting plate through a connecting screw, and the rotating shaft of the pitching angle sensor is fixedly connected with the pitching circular ring through mechanical self-locking; the cylinder body of the side swing hydraulic swing cylinder is fixedly connected with the fourth connecting plate through a connecting screw, and the rotating shaft of the side swing hydraulic swing cylinder is fixedly connected with the pitching circular ring through a connecting screw; the shell of the side-sway angle sensor is fixedly connected with the third connecting plate through a connecting screw, and a rotating shaft of the side-sway angle sensor is fixedly connected with the pitching circular ring through mechanical self-locking; the third connecting plate and the fourth connecting plate are fixedly connected with the side swing end cover through connecting screws; the side-swinging end cover is rotatably connected with a second transmission shaft of the rzeppa constant velocity universal joint through a bearing, in addition, the second transmission shaft is fixedly connected with a tail end flange connecting piece through a key and a fastening screw, and four round holes are formed in the tail end flange connecting piece, so that the wrist and the tail end actuator of the robot can be conveniently and fixedly connected through a bolt group.
The star sleeve, the retainer, the steel balls, the first transmission shaft and the second transmission shaft form a ball-cage constant-velocity universal joint, an output shaft of the hydraulic motor is in rigid connection with the first transmission shaft of the ball-cage constant-velocity universal joint through a coupler, the second transmission shaft is matched with a bearing and is in rotating connection with the side swinging end cover, and the rotating center of the universal joint is overlapped with the centroid of the pitching circular ring.
When the pitching hydraulic swing cylinder acts, the pitching circular ring is driven to rotate at a certain angle around the axial direction A-A of the first connecting plate and the second connecting plate, so that the pitching movement of the wrist with three degrees of freedom can be realized; when the side swing hydraulic swing cylinder acts, the side swing end cover, the third connecting plate and the fourth connecting plate are driven to rotate around the axial direction B-B of the pitching circular ring by a certain angle, so that the side swing movement of the three-degree-of-freedom wrist can be realized; the ball-cage type constant velocity universal joint makes certain angle adjustment along with the actions of the pitching hydraulic oscillating cylinder and the side-oscillating hydraulic oscillating cylinder, and the second transmission shaft of the ball-cage type constant velocity universal joint is driven to rotate by a certain angle when the hydraulic motor acts, so that the autorotation motion of the wrist with three degrees of freedom can be realized; the decoupling of three active input motions of pitching, side swinging and autorotation is realized, so that the motions of three degrees of freedom are mutually independent; in addition, the pitching axis, the side swinging axis and the rotation axis of the wrist with three degrees of freedom intersect at a point in space, so the wrist with three degrees of freedom belongs to a spherical wrist.
The pitching angle sensor can acquire angle signals of the motions of the pitching hydraulic swing cylinder, and further the angle values of the pitching rings rotating around the axial direction A-A of the first connecting plate and the second connecting plate can be obtained according to the position relation among the mechanism components and are regarded as the pitching angle signals of the wrist; the angle signal of the action of the lateral swing hydraulic swing cylinder can be acquired through the lateral swing angle sensor, and the angle value of the rotation of the lateral swing end cover and the connecting rib plate around the axial direction B-B of the pitching circular ring can be further obtained according to the position relation among the mechanism components and is regarded as the lateral swing angle signal of the wrist; the rotation angle signal of the action of the hydraulic motor can be acquired through the self-rotation angle encoder, and the rotation angle value of the second transmission shaft can be further obtained according to the constant-speed transmission relationship of the two transmission shafts of the rzeppa constant-speed universal joint and is regarded as the self-rotation angle signal of the wrist; and finally, the pitching hydraulic oscillating cylinder, the side-swinging hydraulic oscillating cylinder and the hydraulic motor are adjusted and controlled through the feedback of the angle signals of the pitching angle sensor, the side-swinging angle sensor and the self-rotation angle encoder, so that the accurate control of the pose of the robot wrist unit driven by the hydraulic actuator is realized.
In the robot wrist unit driven by the hydraulic actuator, the autorotation motion of the wrist is realized by one hydraulic motor, and the pitching motion and the side swinging motion of the wrist are respectively realized by one hydraulic swinging cylinder.
According to the robot wrist unit driven by the hydraulic actuator, the ball-cage type constant-velocity universal joint belongs to one type of ball-cage type universal joint, the transmission ratio is constant and does not change along with the change of the transmission angle, and the constant-velocity transmission of two transmission shafts can be realized.
According to the robot wrist unit driven by the hydraulic actuator, the base is provided with the four round holes, so that the wrist can be conveniently and fixedly connected with the large arm or the small arm of the robot through the bolt group.
According to the robot wrist unit driven by the hydraulic actuator, the four round holes are formed in the end flange connecting piece, so that the wrist and the end actuator of the robot can be conveniently and fixedly connected through the bolt group.
Above-mentioned hydraulic actuator driven robot wrist unit, hydraulic motor's casing passes through the cylindrical slot of connecting screw rigid coupling in the frame bottom, and hydraulic motor's output shaft and frame rotate to be connected, and the output shaft of motor passes through the shaft coupling and the first transmission shaft rigid coupling of rzeppa constant velocity universal joint simultaneously, and second transmission shaft cooperation bearing rotates with the side pendulum end cover to be connected, the center of rotation of universal joint and the centroid coincidence of pitching the ring.
In the robot wrist unit driven by the hydraulic actuator, the axes of the wrist in pitching motion, side swinging motion and self-moving motion can be converged at one point in the space.
Compared with the background technology, the invention has the following beneficial effects:
1) the pitching axis, the side-swinging axis and the rotation axis of the wrist unit intersect at one point in space to form the spherical wrist, so that the decoupling of three active input motions of pitching, side-swinging and rotation can be realized, the three active input motions become independent motions, the control of the posture of the wrist is simple and convenient, the control precision is high, the posture capability is strong, and the shaking phenomenon of the mechanical arm caused by the motion coupling during the joint matching adjustment is avoided.
2) The self-rotation movement of the wrist unit is realized by one hydraulic motor, the pitching and side swinging movements of the wrist are respectively realized by one hydraulic swinging cylinder, and the wrist unit has the advantages of short transmission chain, compact structure, high integration level, small shape, high power density, high load/self-weight ratio and the like.
3) The side-swinging motion and the pitching motion of the wrist unit are motions formed by two mutually independent hydraulic swinging cylinders through the driving assembly, the structure is more compact and simple, the processing, the manufacturing, the assembly and the replacement are easy, and the uneven phenomenon of jumping under the action of dynamic load is avoided because the transmission for controlling the posture of the wrist does not have a bevel gear or a bevel gear.
4) The rotation motion of the wrist unit is formed by driving the ball-type constant velocity universal joint to rotate by the hydraulic motor, so the rotation motion of the wrist part becomes independent decoupling motion, large-angle rotation can be realized, meanwhile, the ball-type constant velocity universal joint adopts the ball-type constant velocity universal joint, constant velocity transmission can be realized, no transmission error exists, and in addition, the rotational inertia is small during the rotation motion.
5) The invention has wide application occasions, can not only adapt to the traditional working condition requirements, but also adapt to the working conditions of heavy load and some special environments, such as electromagnetic environment, deep sea environment, high-pressure environment and the like.
Drawings
FIG. 1 is a schematic view of the structure of a wrist unit of the robot of the present invention;
FIG. 2 is a front cross-sectional view of the rotation and pitch drive of the robotic wrist unit of the present invention;
FIG. 3 is a front sectional view of the rotation and yaw driving mechanism of the wrist unit of the robot according to the present invention.
In the figure, 1-hydraulic motor, 2-first connecting plate, 3-base, 4-rzeppa constant velocity universal joint, 4-1-second transmission shaft, 4-2-star sleeve, 4-3-retainer, 4-4-steel ball, 4-5-first transmission shaft, 5-pitch hydraulic swing cylinder, 5-1-pitch hydraulic swing cylinder body, 5-2-pitch hydraulic swing cylinder rotating shaft, 6-first pitch ring, 6-1-second pitch ring, 7-yaw angle sensor, 8-third connecting plate, 9-yaw end cap, 10-end flange connector, 11-fourth connecting plate, 12-pitch angle sensor, 13-yaw hydraulic swing cylinder, 13-1-yaw hydraulic swing cylinder body, 13-2-side swing hydraulic swing cylinder rotating shaft, 14-second connecting plate, 15-coupler, 16-rotation angle encoder and 17-bearing.
Detailed Description
The following describes an embodiment of the present invention with reference to fig. 1 to 3. A robot wrist unit driven by a hydraulic actuator comprises a base 3 and a ball-cage type constant velocity universal joint 4, wherein the ball-cage type constant velocity universal joint 4 comprises a first transmission shaft 4-5 and a second transmission shaft 4-1, a hydraulic motor 1 is arranged at the center of the bottom of the base 3, an output shaft of the hydraulic motor 1 vertically penetrates through the base 3 and then is connected with a self-rotation angle encoder 16 and the first transmission shaft 4-5, a shell of the self-rotation angle encoder 16 is fixed with the base 3, a first connecting plate 2 and a second connecting plate 14 which are vertically arranged are symmetrically fixed on the base 3 at two ends of the self-rotation angle encoder 16, a rotation shaft 5-2 of a pitching hydraulic swing cylinder is fixed on the upper portion of the first connecting plate 2, a pitching angle sensor 12 is fixed on the upper portion of the second connecting plate 14, a first pitching ring 6 is fixed on the rotation shaft of the pitching angle sensor 12 through mechanical self-locking, the upper part of a second transmission shaft 4-1 of the ball cage type constant velocity universal joint 4 is connected with a side swing end cover 9 with a bearing 17, the side swing end cover 9 is symmetrically fixed with a third connecting plate 8 and a fourth connecting plate 11 in the direction vertical to the connecting line of the first connecting plate 2 and the second connecting plate 14, the third connecting plate 8 is provided with a side swing angle sensor 7, the fourth connecting plate 11 is fixed with a side swing hydraulic swing cylinder 13, a rotating shaft of the side swing angle sensor 7 is fixed with a second pitching annular 6-2 through mechanical self-locking, the top of the second transmission shaft 4-1 is fixedly connected with a terminal flange connecting piece 10 through a key and a fastening screw, and the terminal flange connecting piece 10 is provided with a screw hole capable of being connected with a terminal actuator of a robot;
When the pitching hydraulic swing cylinder 5 acts, the first pitching ring 6 is driven to rotate around the axial direction A-A of the first connecting plate 2 and the second connecting plate 14, so that the pitching movement of the wrist with three degrees of freedom can be realized; when the side swing hydraulic swing cylinder 13 acts, the side swing end cover 9, the third connecting plate 8 and the fourth connecting plate 11 are driven to rotate around the axial direction B-B of the second pitch and pitch circular ring 6-1, so that the side swing movement of the three-degree-of-freedom wrist can be realized, the ball cage type constant velocity universal joint 4 can make adaptive angle adjustment along with the actions of the pitch and pitch hydraulic swing cylinder 5 and the side swing hydraulic swing cylinder 13, the second transmission shaft 4-1 of the ball cage type constant velocity universal joint 4 is driven to rotate when the hydraulic motor 1 acts, the self-rotation movement of the three-degree-of-freedom wrist can be realized, and therefore the decoupling of three active input movements of pitch, side swing and self-rotation is realized, so that the three degrees-of freedom movements are mutually independent;
the pitch angle sensor 12 can acquire angle signals of the motions of the pitch hydraulic swing cylinder 5, and further the angle value of the rotation of the pitch ring 6 around the axial direction A-A of the first connecting plate 2 and the second connecting plate 14 can be obtained according to the position relation among the mechanism components and is regarded as the pitch angle signal of the wrist; the angle sensor 7 can acquire the angle signal of the action of the side swing hydraulic swing cylinder 13, and further the angle values of the side swing end cover 9, the third connecting plate 8 and the fourth connecting plate 11 rotating around the axial direction B-B of the pitching circular ring 6 can be obtained according to the position relation among the mechanism components and are regarded as the side swing angle signal of the wrist; the rotation angle signal of the action of the hydraulic motor 1 can be acquired through the rotation angle encoder 16, and the rotation angle value of the second transmission shaft 4-1 can be further obtained according to the constant speed transmission relation between the first transmission shaft 4-5 and the second transmission shaft 4-1 of the rzeppa universal joint 4 and is regarded as the rotation angle signal of the wrist; and finally, the pitching hydraulic oscillating cylinder 5, the side-swinging hydraulic oscillating cylinder 13 and the hydraulic motor 1 are regulated and controlled through the feedback of angle signals of the pitching angle sensor 12, the side-swinging angle sensor 7 and the self-rotation angle encoder 16, so that the accurate control of the pose of the robot wrist unit driven by the hydraulic actuator is realized.
Wherein, the transmission ratio of the ball-cage type constant velocity universal joint 4 is constant and does not change along with the change of the transmission angle, the constant velocity transmission of the first transmission shaft 4-5 and the second transmission shaft 4-1 can be realized, and the rotating shaft of the pitching angle sensor 12 is superposed with the centroid of the pitching circular ring 6 through the rotating center of the ball-cage type constant velocity universal joint 4. Four round holes are formed in the base 3 and used for fixedly connecting the wrist unit with the large arm or the small arm of the robot through a bolt group. Four round holes are arranged on the end flange connecting piece 10, so that the wrist and the end actuator of the robot can be conveniently and fixedly connected through a bolt group. The bottom of the base 3 is provided with a cylindrical groove for placing the hydraulic motor 1, the middle part of the cylindrical groove is provided with a round hole extending out of an output shaft of the hydraulic motor 1, four corners of the base 3 are set to be round corners and corner positions to be respectively provided with four round holes, and the wrist and the big arm or the small arm of the robot can be conveniently fixedly connected through a bolt group. The axes of the wrist unit in pitch, roll, and autorotation can converge to a point in space.
The specific working principle of the wrist unit of the invention is as follows:
when the pitching hydraulic swing cylinder 5 acts, the pitching circular ring 6 is driven to rotate at a certain angle around the axial direction A-A of the first connecting plate 2 and the second connecting plate 14, so that the pitching movement of the wrist with three degrees of freedom can be realized; when the side swing hydraulic swing cylinder 13 acts, the side swing end cover 9, the third connecting plate 8 and the fourth connecting plate 11 are driven to rotate by a certain angle around the axial direction B-B of the pitching circular ring 6, so that the side swing movement of the wrist with three degrees of freedom can be realized; the ball-cage type constant velocity universal joint 4 performs certain angle adjustment along with the actions of the pitching hydraulic oscillating cylinder 5 and the side-swinging hydraulic oscillating cylinder 13, and the second transmission shaft 4-1 of the ball-cage type constant velocity universal joint 4 is driven to rotate by a certain angle when the hydraulic motor 1 acts, so that the self-rotation motion of the wrist with three degrees of freedom can be realized; the decoupling of three active input motions of pitching, side swinging and autorotation is realized, so that the motions of three degrees of freedom are mutually independent; in addition, the pitching axis, the side swinging axis and the rotation axis of the wrist with three degrees of freedom intersect at a point in space, so the wrist with three degrees of freedom belongs to a spherical wrist.
According to the control principle of the pose of the wrist unit of the robot driven by the hydraulic actuator in the structure, the pitching angle sensor 12 can be used for collecting the angle signal of the action of the pitching hydraulic swing cylinder 5, and further the angle value of the rotation of the pitching ring 6 around the axial direction A-A of the first connecting plate 2 and the second connecting plate 14 can be obtained according to the position relation among mechanism components and is regarded as the pitching angle signal of the wrist; the sidesway angle sensor 7 can acquire angle signals of the action of the sidesway hydraulic swing cylinder 13, and further angle values of the sidesway end cover 9, the third connecting plate 8 and the fourth connecting plate 11 which rotate around the axial direction B-B of the pitching circular ring 6 can be obtained according to the position relation among the mechanism components and are regarded as the sidesway angle signals of the wrist; the rotation angle signal of the action of the hydraulic motor 1 can be acquired through the rotation angle encoder 16, and the rotation angle value of the second transmission shaft 4-1 can be further obtained according to the constant speed transmission relation between the second transmission shaft 4-1 and the first transmission shaft 4-5 of the rzeppa constant speed universal joint 4 and is regarded as the rotation angle signal of the wrist; and finally, the pitching hydraulic oscillating cylinder 5, the side-swinging hydraulic oscillating cylinder 13 and the hydraulic motor 1 are regulated and controlled through the feedback of angle signals of the pitching angle sensor 12, the side-swinging angle sensor 7 and the self-rotation angle encoder 16, so that the accurate control of the pose of the robot wrist unit driven by the hydraulic actuator is realized.
Claims (6)
1. A hydraulic actuator driven robotic wrist unit, characterized by: the device comprises a base (3) and a ball-cage type constant velocity universal joint (4), wherein the ball-cage type constant velocity universal joint (4) comprises a first transmission shaft (4-5) and a second transmission shaft (4-1), a hydraulic motor (1) is arranged at the center of the bottom of the base (3), an output shaft of the hydraulic motor (1) vertically penetrates through the base (3) and then is connected with a rotation angle encoder (16) and the first transmission shaft (4-5), a shell of the rotation angle encoder (16) is fixed with the base (3), a first connecting plate (2) and a second connecting plate (14) which are vertically arranged are symmetrically fixed on the base (3) at two ends of the rotation angle encoder (16), a pitching hydraulic cylinder swinging rotating shaft (5-2) is fixed on the upper portion of the first connecting plate (2), a pitching angle sensor (12) is fixed on the upper portion of the second connecting plate (14), a first pitching circular ring (6) is fixed on the rotating shaft of the pitching angle sensor (12) through a self-locking mechanism, the upper part of a second transmission shaft (4-1) of the ball cage type constant velocity universal joint (4) is connected with a side swing end cover (9) with a bearing (17), the side swing end cover (9) is symmetrically fixed with a third connecting plate (8) and a fourth connecting plate (11) in the direction vertical to the connecting line of the first connecting plate (2) and the second connecting plate (14), a side swing angle sensor (7) is arranged on the third connecting plate (8), a side swing hydraulic swing cylinder (13) is fixed on the fourth connecting plate (11), a second pitching circular ring (6-2) is fixed on a rotating shaft of the side swing angle sensor (7) through mechanical self-locking, the top of the second transmission shaft (4-1) is fixedly connected with a terminal flange connecting piece (10) through a key and a fastening screw, and a screw hole capable of being connected with a terminal actuator of a robot is arranged on the terminal flange connecting piece (10); when the pitching hydraulic swing cylinder (5) acts, the first pitching ring (6) is driven to rotate around the axial direction A-A of the first connecting plate (2) and the second connecting plate (14), so that the pitching movement of the three-degree-of-freedom wrist can be realized; when the side swing hydraulic swing cylinder (13) acts, the side swing end cover (9), the third connecting plate (8) and the fourth connecting plate (11) are driven to rotate around the axial direction B-B of the second pitch and depression circular ring (6-1), so that the side swing motion of a three-degree-of-freedom wrist can be realized, the ball cage type constant velocity universal joint (4) can make adaptive angle adjustment along with the actions of the pitch and depression hydraulic swing cylinder (5) and the side swing hydraulic swing cylinder (13), and the second transmission shaft (4-1) of the ball cage type constant velocity universal joint (4) is driven to rotate when the hydraulic motor (1) acts, so that the self-rotation motion of the three-degree-of-freedom wrist can be realized, and therefore the decoupling of three active input motions of pitch, side swing and self-rotation is realized, so that the three-degree-of-freedom motions are mutually independent; the pitching angle sensor (12) can acquire the angle signal of the action of the pitching hydraulic swing cylinder (5), and further the angle value of the rotation of the pitching ring (6) around the axial direction A-A of the first connecting plate (2) and the second connecting plate (14) can be obtained according to the position relation among the mechanism components and is regarded as the pitching angle signal of the wrist; the angle signals of the actions of the side swing hydraulic swing cylinder (13) can be collected through the side swing angle sensor (7), and further the angle values of the side swing end cover (9), the third connecting plate (8) and the fourth connecting plate (11) rotating around the axial direction B-B of the pitching circular ring (6) can be obtained according to the position relation among the mechanism components and are regarded as the side swing angle signals of the wrist; the rotation angle signal of the action of the hydraulic motor (1) can be acquired through the self-rotation angle encoder (16), and the rotating angle value of the second transmission shaft (4-1) can be further obtained according to the constant-speed transmission relation of the first transmission shaft (4-5) and the second transmission shaft (4-1) of the ball-cage type constant-speed universal joint (4) and is regarded as the self-rotation angle signal of the wrist; and finally, the pitching hydraulic swing cylinder (5), the side swing hydraulic swing cylinder (13) and the hydraulic motor (1) are adjusted and controlled through the feedback of angle signals of the pitching angle sensor (12), the side swing angle sensor (7) and the rotation angle encoder (16), so that the accurate control of the pose of the robot wrist unit driven by the hydraulic actuator is realized.
2. A hydraulic actuator driven robotic wrist unit according to claim 1, wherein: the transmission ratio of the ball-cage type constant velocity universal joint (4) is constant and does not change along with the change of a transmission angle, the constant velocity transmission of a first transmission shaft (4-5) and a second transmission shaft (4-1) can be realized, and the rotating shaft of the pitching angle sensor (12) is superposed with the centroid of the pitching circular ring (6) through the rotating center of the ball-cage type constant velocity universal joint (4).
3. A hydraulic actuator driven robotic wrist unit according to claim 1, wherein: four round holes are formed in the base (3) and are used for fixedly connecting the wrist unit with the large arm or the small arm of the robot through bolt groups.
4. A hydraulic actuator driven robotic wrist unit according to claim 1, wherein: four round holes are arranged on the end flange connecting piece (10), so that the wrist and the end executor of the robot can be conveniently and fixedly connected through a bolt group.
5. A hydraulic actuator driven robotic wrist unit according to claim 1, wherein: the bottom of the base (3) is provided with a cylindrical groove for placing the hydraulic motor (1), the middle part of the cylindrical groove is provided with a round hole extending out of an output shaft of the hydraulic motor (1), four corners of the base (3) are set to be round corners, the positions of the round corners are respectively provided with four round holes, and the wrist and the big arm or the small arm of the robot can be conveniently fixedly connected through a bolt group.
6. A hydraulic actuator driven robotic wrist unit according to any one of claims 1 to 5, wherein: the axes of the wrist unit in pitch, roll, and autorotation can converge to a point in space.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010562662.3A CN111843989A (en) | 2020-06-19 | 2020-06-19 | Robot wrist unit driven by hydraulic actuator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010562662.3A CN111843989A (en) | 2020-06-19 | 2020-06-19 | Robot wrist unit driven by hydraulic actuator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111843989A true CN111843989A (en) | 2020-10-30 |
Family
ID=72987619
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010562662.3A Pending CN111843989A (en) | 2020-06-19 | 2020-06-19 | Robot wrist unit driven by hydraulic actuator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111843989A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115107079A (en) * | 2022-04-26 | 2022-09-27 | 腾讯科技（深圳）有限公司 | Mechanical wrist joint, mechanical arm and robot |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2839727Y (en) * | 2005-06-27 | 2006-11-22 | 游洪德 | Duplex plain edition rzeppa universal joint |
| CN103341865A (en) * | 2013-07-05 | 2013-10-09 | 大连理工大学 | Three-freedom-degree constant speed decoupling space robot active spherical wrist and universal compliant control method |
| CN110027010A (en) * | 2019-04-15 | 2019-07-19 | 太原理工大学 | A kind of hydraulic direct-drive Three-degree-of-freedom spherical wrist |
| CN110171015A (en) * | 2019-05-21 | 2019-08-27 | 太原理工大学 | A kind of hydraulic-driven Three-degree-of-freedom spherical wrist of mobile decoupling |
| WO2020029584A1 (en) * | 2018-08-09 | 2020-02-13 | 江苏钧微动力科技有限公司 | Hydraulically powered joint for robot |
-
2020
- 2020-06-19 CN CN202010562662.3A patent/CN111843989A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2839727Y (en) * | 2005-06-27 | 2006-11-22 | 游洪德 | Duplex plain edition rzeppa universal joint |
| CN103341865A (en) * | 2013-07-05 | 2013-10-09 | 大连理工大学 | Three-freedom-degree constant speed decoupling space robot active spherical wrist and universal compliant control method |
| WO2020029584A1 (en) * | 2018-08-09 | 2020-02-13 | 江苏钧微动力科技有限公司 | Hydraulically powered joint for robot |
| CN110027010A (en) * | 2019-04-15 | 2019-07-19 | 太原理工大学 | A kind of hydraulic direct-drive Three-degree-of-freedom spherical wrist |
| CN110171015A (en) * | 2019-05-21 | 2019-08-27 | 太原理工大学 | A kind of hydraulic-driven Three-degree-of-freedom spherical wrist of mobile decoupling |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115107079A (en) * | 2022-04-26 | 2022-09-27 | 腾讯科技（深圳）有限公司 | Mechanical wrist joint, mechanical arm and robot |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110171015B (en) | Motion decoupling hydraulic drive three-degree-of-freedom spherical wrist | |
| CN111604935B (en) | Electromagnetically-driven spherical robot wrist with two degrees of freedom and control method thereof | |
| CN112476478B (en) | Bionic rope-driven four-degree-of-freedom arm oriented to man-machine cooperation | |
| US5159988A (en) | Articulated structure for legged walking robot | |
| CN103341865B (en) | Three-freedom-degree constant speed decoupling space robot active spherical wrist and universal compliant control method | |
| CN106272399B (en) | Hollow bias-crossing type six-freedom-degree spraying robot | |
| US9637222B2 (en) | Multi-axis pivot assembly for control sticks and associated systems and methods | |
| CN110666774B (en) | Three-degree-of-freedom rope driving joint module based on parallel mechanism | |
| WO2018223363A1 (en) | Three-degrees-of-freedom decoupled spherical parallel mechanism | |
| CN100560307C (en) | The active Wrist mechanism that is used for mechanical arm or snake-shaped robot | |
| US8127871B2 (en) | Frame walker predicated on a parallel mechanism | |
| CN101116971A (en) | Movement decoupling spherical surface rotating paralleling mechanism can be used as the robot wrist joint | |
| CN109514596B (en) | Double-cross hinge three-degree-of-freedom parallel joint mechanism | |
| US11897128B2 (en) | Modular multi-hinge retractable rigid-flexible coupling space manipulator based on origami structure | |
| CN110450147B (en) | Crank slide bar mechanical arm with rear-mounted gravity center of spring counterweight and motor rotation angle algorithm thereof | |
| WO2021243515A1 (en) | Electromagnetic driving two-degrees of freedom spherical robot wrist and control method thereof | |
| CN111843989A (en) | Robot wrist unit driven by hydraulic actuator | |
| CN104608146A (en) | Novel mechanical arm based on double-bevel deflection joints | |
| CN101590650A (en) | The three-rotation freedom parallel mechanism of decoupling zero | |
| CN106625591B (en) | Three-translation two-rotation five-degree-of-freedom parallel mechanism | |
| CN204487596U (en) | Based on the New Type of Robot Arm in double inclined plane deflection joint | |
| Klas et al. | A compact, lightweight and singularity-free wrist joint mechanism for humanoid robots | |
| CN104690743A (en) | Robot wrist joint structure based on single-stator multi-degree-of-freedom ultrasonic motor | |
| CN108714887B (en) | Spatial parallel mechanism with three degrees of freedom | |
| Wang et al. | Type synthesis of 3T2R decoupled hybrid mechanisms with large bearing capacity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201030 |
|
| RJ01 | Rejection of invention patent application after publication |