CN112298398A - Bionic quadruped robot - Google Patents

Bionic quadruped robot Download PDF

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Publication number
CN112298398A
CN112298398A CN202011383548.0A CN202011383548A CN112298398A CN 112298398 A CN112298398 A CN 112298398A CN 202011383548 A CN202011383548 A CN 202011383548A CN 112298398 A CN112298398 A CN 112298398A
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China
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head
tail
branched chain
connecting piece
trunk
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CN202011383548.0A
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CN112298398B (en
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郭为忠
李子岳
林荣富
赵辰尧
和家平
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Shanghai Jiaotong University
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Shanghai Jiaotong University
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D57/00Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track
    • B62D57/02Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members
    • B62D57/032Vehicles characterised by having other propulsion or other ground- engaging means than wheels or endless track, alone or in addition to wheels or endless track with ground-engaging propulsion means, e.g. walking members with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Manipulator (AREA)
  • Toys (AREA)

Abstract

A biomimetic quadruped robot comprising: four shank mechanisms and a plurality of head and tail constitutional unit of being connected with the trunk, wherein: every shank mechanism provides six degrees of freedom, and every head and the tail constitutional unit provide two degrees of freedom, connect head and the tail constitutional unit in order according to the flexibility ratio needs to be connected with the trunk in order simulating neck and afterbody. The invention is based on bionics, all adopt the parallel mechanism to carry on the structural design, have stronger bearing capacity compared with the series structure, therefore have better security; through reasonable structural design, all driving pairs of the mechanical dinosaur are ensured to be moving pairs, and sufficient power and strength are ensured by adopting hydraulic cylinder driving; the relative poses and sizes of the leg mechanism and the head and tail structure units refer to the size of a recovery model of the dinosaur fossil, so that the posture of the dinosaur can be better simulated; the head and tail structure units of the mechanism pose can be selected and combined according to the required motion flexibility, and the structure is simplified.

Description

Bionic quadruped robot
Technical Field
The invention relates to a technology in the field of robots, in particular to a dinosaur-based bionic quadruped robot.
Background
With the development of economic society, the living standard of people is continuously improved, the demand of mental life is increased, and the application of scientific technology to the mental life of people is the trend of the world. Dinosaurs are living beings which people can know well in ears and are prehistoric living beings which are very popular and popular among many people, so that mechanical dinosaurs have great development potential in the fields of theme parks, large-scale activities, stage performances, educational science popularization and the like.
At present, the development of the domestic large mechanical dinosaur field is slow, the mechanical dinosaur has no mobility or only has a local structure with mobility by using a model, and has no autonomous walking capability; australia has been the world's lead in this area, but most designs employ tandem or planar mechanisms and require secondary support structures to increase load bearing capacity. In the large mechanical dinosaur market, the existing products have some common problems, the degree of freedom of the whole machine is small, and the motion sense of the simulated dinosaur is hard due to insufficient flexibility of the whole machine; mechanical dinosaurs often need to be supported by means of certain auxiliary equipment such as rails, supports and the like, and authenticity is greatly reduced.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a bionic quadruped robot, which adopts a parallel mechanism to improve the bearing capacity and is assisted by bionics to fully simulate the appearance and behavior characteristics of dinosaurs.
The invention is realized by the following technical scheme:
the invention relates to a bionic quadruped robot, which comprises: four shank mechanisms and a plurality of head and tail constitutional unit of being connected with the trunk, wherein: every shank mechanism provides six degrees of freedom, and every head and the tail constitutional unit provide two degrees of freedom, connect head and the tail constitutional unit in order according to the flexibility ratio needs to be connected with the trunk in order simulating neck and afterbody.
The leg mechanism comprises: thigh parallel mechanism and ankle joint parallel mechanism through the connecting piece connection, wherein: the thigh parallel mechanism takes the trunk as a static platform, takes the connecting piece as a movable platform, and the ankle parallel mechanism takes the connecting piece as a static platform.
The thigh parallel mechanism comprises: three driving branches and a rotating branch, wherein: two driving branched chains and a rotating branched chain are arranged between the trunk and the connecting piece, one end of the other driving branched chain is connected with the trunk, and the other end of the other driving branched chain is connected with the rotating branched chain.
The rotation branched chain is hooke hinge, connecting rod and revolute pair that connect gradually, wherein: the Hooke hinge is connected with the trunk, the revolute pair is connected with the connecting piece, and the Hooke hinge is used as a rotation center of the thigh parallel mechanism.
The ankle joint parallel mechanism comprises: set up three drive branched chain and ball hinge between connecting piece and sole, wherein: the connecting piece is used as a static platform, the sole is used as a movable platform, the ball hinge is fixed on the connecting piece and connected with the sole, and the ball hinge is used as a rotation center of the ankle joint parallel mechanism.
The sequential connection means that every two head-tail structural units are connected in series end to end through a connecting sheet, and the connecting sheet is used as a movable platform of the previous head-tail structural unit and a static platform of the next head-tail structural unit.
The head and tail structure unit comprises: two drive branches and a hooke hinge, wherein: the Hooke hinge is arranged on the side of the movable platform, and the center of the Hooke hinge is not on the connection line of the centers of the two ball hinges of the driving branched chain.
The drive branched chain is a Hooke hinge, a moving pair and a ball hinge which are connected in sequence, wherein: and the Hooke hinge is connected with the static platform.
The sliding pair is two connecting rods which are connected with each other.
The moving pair is driven by a servo hydraulic cylinder.
The bionic quadruped robot further comprises a bionic base, and the bionic base specifically comprises: in the overall arrangement of the mechanism, the arrangement mode of the triangle skeleton is referred, and the rotation center of the mechanism movement is just positioned at the bone joint. The rotation center of the thigh parallel mechanism is positioned at a hooke hinge of the rotating branched chain, and the hooke hinge is arranged at a hip joint of the real triangle dragon; the rotation center of the ankle joint parallel mechanism is positioned at the ball hinge branched chain, and the arrangement position of the ball hinge refers to the ankle joint position of a real triangle dragon; the sequential connection arrangement mode of the head and tail structural units refers to the spinal segmental connection mode of the dinosaur.
Technical effects
The invention integrally solves the problems that the prior mechanical dinosaur needs to support movement by means of a track, a bracket and the like, so that the large mechanical dinosaur has less freedom and hard head and tail rotation caused by movement; the invention totally adopts a parallel mechanism based on bionics to carry out structural design, the structural design of the whole machine ensures the motion flexibility of the mechanical dinosaur, a large number of degrees of freedom provided by the mechanism and the structural design based on bionics; compared with the prior art, the invention does not need additional supporting structures such as a track and the like to assist the movement; the large number of degrees of freedom provided by the mechanism brings higher motion flexibility; the head and tail structure units of the mechanism pose can be selected and combined according to the required motion flexibility, the structure is simplified, the flexibility of product design is improved, all driving pairs of the mechanical dinosaur are guaranteed to be moving pairs, and sufficient power and strength are guaranteed by adopting hydraulic cylinder driving; the relative poses and sizes of the leg mechanism and the head and tail structure units refer to the size of a recovery model of the dinosaur fossil, so that the posture of the dinosaur can be better simulated;
drawings
FIG. 1 is a schematic structural diagram of the present embodiment;
FIG. 2 is a schematic structural view of the leg mechanism;
FIG. 3 is a schematic structural view of an ankle parallel mechanism;
FIG. 4 is a schematic structural view of the tail portion;
in the figure: the robot comprises a head part 1, a head-tail structure unit 2, a trunk 3, a leg mechanism 4, a connecting piece 5, first to eighth driving branched chains 6 to 13, a rotating branched chain 14, a first hook hinge 15, a first connecting rod 16, a rotating pair 17, a first ball hinge 18, a sole 19, a second hook hinge 20, a second ball hinge 21, a second connecting rod 22, a third connecting rod 23, a third hook hinge 24 and a connecting piece 25.
Detailed Description
As shown in fig. 1, the present embodiment takes a triangle structure as an example, and specifically includes: head 1, four head and tail constitutional units 2, four shank mechanisms 4 and truck 3, wherein: head 1 is connected through a head and the tail constitutional unit 2 with truck 3, and four shank mechanisms 4 are connected with truck 3 respectively, and three head and the tail constitutional unit 2 that are connected in order by connection piece 25 form the afterbody and are connected with truck 3.
As shown in fig. 2, the leg mechanism 4 includes: thigh parallel mechanism and ankle joint parallel mechanism through connecting piece 5 connection, wherein: the thigh parallel mechanism takes the trunk 3 as a static platform, takes the connecting piece 5 as a movable platform, and the ankle parallel mechanism takes the connecting piece 5 as a static platform.
The thigh parallel mechanism comprises: first to third driving branches 6-8 and a rotating branch 14, wherein: the first driving branched chain 6, the second driving branched chain 7 and the rotating branched chain 14 are arranged between the trunk 3 and the connecting piece 5, one end of the third driving branched chain 8 is connected with the trunk 3, and the other end of the third driving branched chain is connected with the first connecting rod 16 of the rotating branched chain 14.
The rotating branched chain 14 is a first hooke hinge 15, a first connecting rod 16 and a rotating pair 17 which are connected in sequence, wherein: the first hooke hinge 15 is connected with the trunk 3, and the revolute pair 17 is connected with the connecting piece 5.
The first Hooke's hinge 15 is used as the rotation center of the thigh parallel mechanism.
As shown in fig. 3, the ankle parallel mechanism includes: fourth to sixth drive branches 9-11, first ball hinge 18 and sole 19, wherein: the fourth to sixth driving branched chains 9 to 11 and the first ball hinge 18 are arranged between the connecting piece 5 and the sole 19, the connecting piece 5 serves as a static platform, the sole 19 serves as a movable platform, and the fixed end of the first ball hinge 18 is connected with the connecting piece 5.
The first ball hinge 18 serves as a rotation center of the ankle parallel mechanism.
As shown in fig. 4, the sequential connection means that every two head-tail structural units 2 are connected in series end to end through a connecting piece 25, and the connecting piece 25 serves as a moving platform of the previous head-tail structural unit 2 and serves as a static platform of the next head-tail structural unit 2.
The head-tail structure unit 2 comprises: set up seventh drive branched chain 12, eighth drive branched chain 13 and third hooke hinge 24 between quiet platform and moving platform, wherein: the hooke joint of the third hooke joint 24 is disposed at the movable platform side, and the hooke joint is not collinear with the second spherical joints 21 of the seventh driving branched chain 12 and the eighth driving branched chain 13.
As shown in fig. 2 to 4, the first to eighth driving branched chains 6 to 13 are a second hooke hinge 20, a sliding pair and a second ball hinge 21, which are connected in sequence, wherein: the second hooke hinge 20 is connected to the stationary platform.
The moving pair is composed of a second connecting rod 22 and a third connecting rod 23 which are connected with each other.
The moving pair is driven by a servo hydraulic cylinder.
The trunk 3 is a rigid frame.
The first driving branch chain to the third driving branch chains 6-8 of the thigh parallel mechanism are used as driving pairs to provide three degrees of freedom, namely the connecting piece 5 has three rotational degrees of freedom and swings back and forth, left and right and pitching; the moving pairs from the fourth driving branched chain to the sixth driving branched chains 9-11 of the ankle joint parallel mechanism are used as driving, three degrees of freedom are provided, namely, the sole 19 has three rotational degrees of freedom, and the flexibility of the ankle joint is ensured; the head 1 and the body 3 are connected through a head-tail structural unit 2, the body 3 serves as a static platform, the head 1 serves as a movable platform, and the moving pair of the seventh driving branched chain 12 and the eighth driving branched chain 13 provides two degrees of freedom, namely the head 1 has two degrees of freedom of rotation, pitching and rolling; the tail part is formed by three head-tail structure units 2 through two connecting pieces 25, each head-tail structure unit 2 provides two degrees of freedom, and the total is six degrees of freedom, namely the tail part has six rotational degrees of freedom; the sequential connection of the head and tail structural units 2 simulates the vertebration of animals, and the number of the head and tail structural units 2 can be added according to requirements if more flexible necks and tails are needed. The embodiment has 32 degrees of freedom, can realize walking, turning, shaking head, nodding, tail swinging and other actions, the parallel mechanism improves the bearing capacity of the robot while providing motion flexibility, and the servo hydraulic cylinder driving mode is more suitable for the requirement of large machinery. The outer covering of the present embodiment can simulate the motion of a triangle dragon.
The relative poses and sizes of the leg mechanism 4 and the head and tail structure unit 2 refer to the size of a recovery model of a dinosaur fossil, so that the motion of the robot is closer to the real motion of the dinosaur. When the mechanism is large-sized, the mechanism can completely use the moving pair drive, and when the mechanism is small-sized, the drive joint is modified according to the requirement, and the specific modification scheme is as follows: and removing the third driving branched chains 8 of all the thigh parallel mechanisms, and driving the thigh parallel mechanisms by adopting the first driving branched chains 6, the second driving branched chains 7 and the revolute pairs 17 together.
Each leg of the bionic quadruped robot has six degrees of freedom, each head-tail structure unit has two degrees of freedom, the number of the head-tail structure units can be selected according to requirements, and the whole robot provides sufficient degrees of freedom to ensure the reality of dinosaur motion simulation while getting rid of an additional supporting structure; the structural arrangement of the dinosaur skeleton is based on bionics, and the rotation center of the key mechanism is arranged at the joint of the dinosaur skeleton, so that the overall structural design is closer to the original skeleton structure of the dinosaur, and the dinosaur skeleton structure is more suitable for simulating the body state of the dinosaur.
Through specific practical experiments, by adopting the structure in the embodiment, the structure is 1: modeling is carried out, motion gait design is carried out in Matlab, a UG NX solver is used for motion simulation, and it can be found that the mechanical dinosaur in the embodiment can realize flat-ground diagonal gait walking with the stride not more than 580mm and turning diagonal gait walking with the turning radius of 5m, and can realize actions of shaking head, nodding head, swinging tail and the like so as to simulate the dinosaur motion posture.
Compared with the existing similar products, the degree of freedom of movement is remarkably improved, the device has 32 degrees of freedom, and the degree of freedom can be further increased according to the requirement of the degree of flexibility of movement due to a segmental design method of head and tail structural units; in the embodiment, the head part and the body part are temporarily rigid structures, but enough secondary development space is reserved, and the degree of freedom can be further increased if a new design mechanism is added on the basis of the embodiment; the embodiment can realize straight line and turning walking by using diagonal gait without additional auxiliary supporting equipment, and can better simulate the posture of the dinosaur.
The foregoing embodiments may be modified in many different ways by those skilled in the art without departing from the spirit and scope of the invention, which is defined by the appended claims and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (7)

1. A biomimetic quadruped robot, comprising: four shank mechanisms and a plurality of head and tail constitutional unit of being connected with the trunk, wherein: each leg mechanism provides six degrees of freedom, each head-tail structure unit provides two degrees of freedom, and the head-tail structure units are sequentially connected according to the requirement of flexibility to simulate the connection of the neck and the tail with the trunk;
the leg mechanism comprises: thigh parallel mechanism and ankle joint parallel mechanism through the connecting piece connection, wherein: the thigh parallel mechanism takes a trunk as a static platform, takes a connecting piece as a movable platform, and the ankle parallel mechanism takes the connecting piece as a static platform;
the thigh parallel mechanism comprises: three driving branches and a rotating branch, wherein: the two driving branched chains and the rotating branched chain are arranged between the trunk and the connecting piece, one end of the other driving branched chain is connected with the trunk, and the other end of the other driving branched chain is connected with the rotating branched chain;
the ankle joint parallel mechanism comprises: set up three drive branched chain and ball hinge between connecting piece and sole, wherein: the connecting piece is used as a static platform, the sole is used as a movable platform, the ball hinge is fixed on the connecting piece and connected with the sole, and the ball hinge is used as a rotation center of the ankle joint parallel mechanism.
2. The bionic quadruped robot as claimed in claim 1, wherein the rotating branched chain comprises a hooke hinge, a connecting rod and a rotating pair which are connected in sequence, wherein: the Hooke hinge is connected with the trunk, the revolute pair is connected with the connecting piece, and the Hooke hinge is used as a rotation center of the thigh parallel mechanism.
3. The bionic quadruped robot as claimed in claim 1, wherein the sequential connection means that every two head-tail structure units are connected in series end to end through a connecting sheet, and the connecting sheet is used as a movable platform of the previous head-tail structure unit and as a static platform of the next head-tail structure unit.
4. The biomimetic quadruped robot according to claim 1 or 3, wherein the head-tail structure unit comprises: two drive branches and a hooke hinge, wherein: the Hooke hinge is arranged on the side of the movable platform, and the center of the Hooke hinge is not on the connection line of the centers of the two ball hinges of the driving branched chain.
5. The bionic quadruped robot as claimed in claim 1, wherein the driving branched chain is a hooke hinge, a moving pair and a ball hinge which are connected in sequence, wherein: and the Hooke hinge is connected with the static platform.
6. The biomimetic quadruped robot as recited in claim 5, wherein the moving pair is two connecting rods connected with each other.
7. The bionic quadruped robot as claimed in claim 1 or 5, wherein the moving pair is driven by a servo hydraulic cylinder.
CN202011383548.0A 2020-12-01 2020-12-01 Bionic quadruped robot Expired - Fee Related CN112298398B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113478464A (en) * 2021-07-22 2021-10-08 中北大学 Parallel bionic moving platform with adjustable gravity center

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CN105965514A (en) * 2016-05-09 2016-09-28 上海理工大学 Bionic hydraulic four-foot machine dinosaur structure
CN205706944U (en) * 2016-02-18 2016-11-23 常州恐龙园股份有限公司 A kind of bionical dinosaur quadruped robot mechanism
CN108481308A (en) * 2018-04-04 2018-09-04 嘉兴学院 A kind of human emulated robot based on pneumatic muscles Yu cylinder series-parallel connection
US20190091592A1 (en) * 2017-09-22 2019-03-28 Dash Robotics, Inc. Physical device simulating the appearance and movement of a two-legged creature
WO2020081630A2 (en) * 2018-10-17 2020-04-23 Petoi, Llc Robotic animal puzzle

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Publication number Priority date Publication date Assignee Title
CN104440921A (en) * 2014-11-07 2015-03-25 韩方元 Multi-translational-degree-of-freedom parallelogram complex kinematic pair
CN204296909U (en) * 2014-12-25 2015-04-29 中国矿业大学 One kind humanoid robot series parallel type pedipulator
CN205706944U (en) * 2016-02-18 2016-11-23 常州恐龙园股份有限公司 A kind of bionical dinosaur quadruped robot mechanism
CN105965514A (en) * 2016-05-09 2016-09-28 上海理工大学 Bionic hydraulic four-foot machine dinosaur structure
US20190091592A1 (en) * 2017-09-22 2019-03-28 Dash Robotics, Inc. Physical device simulating the appearance and movement of a two-legged creature
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WO2020081630A2 (en) * 2018-10-17 2020-04-23 Petoi, Llc Robotic animal puzzle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113478464A (en) * 2021-07-22 2021-10-08 中北大学 Parallel bionic moving platform with adjustable gravity center

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Granted publication date: 20211026