CN113183181B

CN113183181B - Rigid-flexible coupling mechanical arm and robot

Info

Publication number: CN113183181B
Application number: CN202110441688.7A
Authority: CN
Inventors: 吴昌渠; 王文彪; 鲍官军
Original assignee: Zhejiang University of Technology ZJUT
Current assignee: Zhejiang University of Technology ZJUT
Priority date: 2021-04-23
Filing date: 2021-04-23
Publication date: 2022-10-14
Anticipated expiration: 2041-04-23
Also published as: CN113183181A

Abstract

The invention discloses a rigid-flexible coupling mechanical arm which comprises an inner framework formed by connecting a plurality of framework monomers in series, a plurality of groups of pneumatic muscles surrounding the inner framework and arranged between the adjacent framework monomers, wherein the inner framework is formed by connecting a plurality of framework monomers in series; adjacent framework monomers are movably connected; the framework single bodies are circumferentially provided with a plurality of pairs of pneumatic muscle interfaces, and each group of pneumatic muscles are correspondingly arranged on the pneumatic muscle interfaces oppositely arranged on the adjacent framework single bodies; the pneumatic muscle interfaces oppositely arranged on the adjacent framework monomers comprise a sealing fixed interface and an inflation interface for inflating pneumatic muscles; and the framework monomer is also provided with a trachea interface communicated with the corresponding inflation interface in the circumferential direction. According to the invention, the flexible pneumatic muscles are arranged on the periphery of the internal framework, so that the mechanical arm has the advantages of a rigid robot and a flexible robot at the same time, and meanwhile, the flexibility is high.

Description

Rigid-flexible coupling mechanical arm and robot

Technical Field

The invention relates to the technical field of robots, in particular to a rigid-flexible coupling mechanical arm and a robot.

Background

With the development and application of robots, people in non-industrial fields such as services, medical treatment, entertainment and the like are increasingly replaced by robots. In many cases, a conventional robot cannot be fully qualified for work, and particularly, a workflow of the robot cannot be comprehensively designed in advance under the condition that a working position is changed or an environment is unknown. Under the requirements of special conditions and environments, light mechanical arms are produced. Lightweight arms generally require light weight, compactness, flexibility, high load/weight ratios and good environmental interaction. Although rigid industrial robots can exhibit some flexibility through control methods (force control, impedance control), this "flexibility" is very limited in nature and not truly flexible due to the effects of delays in the sensor data acquisition control loop, motor inertia, mechanical bandwidth, and the like. The flexibility of lightweight robotic arms comes primarily from joint flexibility and part flexibility. The structural components are generally made of materials with higher rigidity and lower flexibility; the joint adopts a harmonic reducer with a large reduction ratio to obtain certain flexibility, but the rigidity of the flexible joint is still large, and the impact resistance is still limited.

The continuum robot under the software has excellent adaptability, and has wide application prospects in a plurality of fields such as medical rehabilitation, old-assisting and disabled-assisting, exoskeleton, continuous operation, complex environment monitoring and detection, space on-orbit operation and the like. However, due to the flexibility of the soft robot, the soft robot is easily interfered by the outside during the moving process, so that the robot is accidentally turned and twisted.

The patent specification with the publication number of CN108943010B discloses a pneumatic control type rigid-flexible coupling modular soft mechanical arm, which comprises an air bag structure used for controlling the movement of the mechanical arm by carrying out unidirectional inflation or deflation control on an inner cavity, wherein the air bag structure comprises at least one air bag module, the air bag module is formed by combining a plurality of air bag bodies arranged along the circumferential direction, the air bag module is provided with a fixing structure of the air bag bodies used for radially pulling and connecting the air bag modules, and the fixing structures are arranged at intervals along the axial direction of the air bag modules and are used for improving the loading capacity of the mechanical arm and enabling all the air bag bodies of the air bag modules to mutually perform coupling movement. The biggest shortcoming of this scheme lies in that the arm main part is the gasbag structure, and the structural strength of whole arm is lower.

The patent specification with the publication number of CN106313034B discloses a rigid-flexible coupling flexible mechanical arm, which comprises a machine base, an actuating device and a plurality of driving units which are connected with the machine base and the actuating device and have the same structure and are sequentially connected in series, wherein a flexible protective cover is arranged outside the whole mechanical arm; drive unit mainly include 4 pneumatic tendons, 4 light connecting rods, two connection pads, two supports, little pneumatic tendon, the both ends of pneumatic tendon are connected with the connection pad respectively, be equipped with the support respectively on the connection pad, two liang of a set of connecting rods, its one end is connected with the connection pad through the universal joint pin that sets up on the support respectively, the other end of each group's connecting rod is crossing to be connected through the cylindric lock axle on the connecting piece respectively with the other end of another group's connecting rod, the both ends of little pneumatic tendon are connected with above-mentioned connecting piece through the screw hole respectively, the big end and the tip of two adjacent drive unit's pneumatic tendon share a connection pad. The biggest disadvantage of this solution is the poor flexibility.

Disclosure of Invention

An object of the present invention is to provide a rigid-flexible coupling robot arm, which has the advantages of both rigid and flexible robots and high flexibility by arranging flexible pneumatic muscles at the periphery of an internal skeleton.

A rigid-flexible coupling mechanical arm comprises an inner framework formed by connecting a plurality of framework monomers in series, and a plurality of groups of pneumatic muscles arranged between the adjacent framework monomers and surrounding the inner framework; adjacent framework monomers are movably connected;

the framework single bodies are circumferentially provided with a plurality of pairs of pneumatic muscle interfaces, and each group of pneumatic muscles are correspondingly arranged on the pneumatic muscle interfaces oppositely arranged on the adjacent framework single bodies; the pneumatic muscle interfaces oppositely arranged on the adjacent framework monomers comprise a sealing fixed interface and an inflation interface for inflating pneumatic muscles; and the framework monomer is also provided with a trachea interface communicated with the corresponding inflation interface in the circumferential direction.

In the scheme, a group of pneumatic muscles are arranged between the adjacent framework monomers, the mechanical arm is divided into a plurality of joints which can be independently controlled, the flexibility of the mechanical arm is improved, meanwhile, the rigidity of the flexible mechanical arm is improved by the internal framework, and the mechanical arm has the advantages of a rigid robot and a flexible robot.

Preferably, a pair of connecting lugs are respectively arranged at two ends of the framework monomer, and horizontal connecting lines of the connecting lugs which are oppositely arranged are mutually vertical; the design can ensure that the installation states of any two framework monomers are consistent in the process of connecting the internal framework monomers in series; the adjacent framework monomers are movably connected through universal shaft joints arranged on the two pairs of connecting lugs which are matched with each other.

Preferably, the universal joint comprises a spider collar and connecting pieces arranged on four sides of the spider collar and projecting into the corresponding coupling lugs.

Preferably, each pair of pneumatic muscle interfaces comprises a sealed fixation interface and an inflation interface.

Preferably, the framework monomer is also provided with a fixed seat used for mounting each pair of pneumatic muscle interface and air pipe interface along the circumferential direction, and the sealing fixed interface and the inflation interface are respectively arranged on the opposite surfaces of the fixed seats; an air passage is arranged in the fixed seat, and the air pipe connector is communicated with the inflation connector through the air passage.

Preferably, each set of pneumatic muscles includes four and is distributed at equal angles in the circumferential direction of the inner skeleton. The four pneumatic muscles are arranged, so that the requirement of the motion space freedom degree of the mechanical arm is met.

Preferably, the pneumatic muscle is made of silica gel.

The invention also provides a rigid-flexible coupling robot which comprises the rigid-flexible coupling mechanical arm.

The invention has the beneficial effects that:

the internal framework designed by the invention can realize the movement of any joint in any direction within the range of +/-30 degrees; meanwhile, the movement precision is higher than that of pure pneumatic muscle movement through the constraint of the internal framework; and the exterior is wrapped by flexible pneumatic muscles, so that the flexible robot shows flexibility to the outside and has the advantages of both a rigid robot and a flexible robot.

Drawings

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

FIG. 2 is a schematic illustration of an explosive structure according to the present invention;

FIG. 3 is a schematic diagram of the structure of a backbone monomer;

fig. 4 is a schematic structural view of a universal joint.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1-4, a rigid-flexible coupling mechanical arm comprises an internal framework 1 formed by connecting a plurality of framework monomers 11 in series, and a plurality of groups of pneumatic muscles 2 surrounding the internal framework 1 and arranged between the adjacent framework monomers 11; the pneumatic muscle 2 is made of silica gel material; the adjacent framework monomers 11 are movably connected.

In this embodiment, a pair of connecting lugs 111 is respectively disposed at two ends of each single frame 11, and the adjacent single frame 11 is movably connected through universal joints 12 mounted on the two pairs of connecting lugs 111 that are mutually matched.

Specifically, the universal joint 12 includes a spider 121 and connecting pieces 122 disposed on four sides of the spider 121, and the connecting lug 111 is provided with a shaft hole 1111 into which the corresponding connecting piece 122 extends; in order to ensure that the installation states of any two framework single bodies 11 are consistent in the process of serially connecting the framework single bodies 11, connecting lines between the shaft holes 1111, which are oppositely arranged on two pairs of connecting lugs 111, on the framework single bodies 11 are perpendicular to each other.

The 11 circumference of skeleton monomer is provided with a plurality of pairs of pneumatic muscle interfaces, and every pneumatic muscle of group 2 corresponds and sets up on the pneumatic muscle interface of the relative setting of adjacent skeleton monomer 11.

In this embodiment, the framework unit 11 is circumferentially provided with four fixing seats 112 for mounting each pair of pneumatic muscle interfaces, that is, each set of pneumatic muscles 2 includes four fixing seats 112, and the fixing seats 112 are distributed on the inner framework 1 in the circumferential direction at equal angles; each pair of pneumatic muscle interfaces comprises a sealing fixing interface 113 and an inflation interface 114 which are respectively arranged on the opposite surfaces of the fixing seat 112, and one of the pneumatic muscle interfaces oppositely arranged on the adjacent framework single bodies 11 is the sealing fixing interface 113, and the other pneumatic muscle interface is the inflation interface 114, so that the pneumatic muscle 2 can be fixed and inflated.

In order to conveniently inflate each pneumatic muscle 2, an air passage is provided in the fixing base 112, and each fixing base 112 is further provided with an air pipe connector 115, and the air pipe connector 115 is communicated with the inflation connector 114 through the air passage.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.

Claims

1. A rigid-flexible coupling mechanical arm, comprising: the pneumatic muscle building framework comprises an inner framework formed by connecting a plurality of framework monomers in series, a plurality of groups of pneumatic muscles surrounding the inner framework and arranged between the adjacent framework monomers; adjacent framework monomers are movably connected;

the framework single bodies are circumferentially provided with a plurality of pairs of pneumatic muscle interfaces, and each group of pneumatic muscles are correspondingly arranged on the pneumatic muscle interfaces oppositely arranged on the adjacent framework single bodies; the pneumatic muscle interfaces oppositely arranged on the adjacent framework monomers comprise a sealing fixed interface and an inflation interface for inflating pneumatic muscles; the framework monomer is also provided with a trachea interface communicated with the corresponding inflation interface in the circumferential direction;

a pair of connecting lugs are respectively arranged at two ends of the framework monomer, and horizontal connecting lines of the connecting lugs which are arranged oppositely are mutually vertical; the adjacent framework monomers are movably connected through universal shaft joints arranged on the two pairs of connecting lugs which are matched with each other;

the universal shaft joint comprises a cross shaft ring and connecting pieces arranged on four side surfaces of the cross shaft ring and extending into corresponding connecting lugs.

2. The rigid-flexible coupled robotic arm of claim 1, wherein: each pair of pneumatic muscle interfaces comprises a sealing fixed interface and an inflation interface.

3. The rigid-flexible coupled robotic arm of claim 2, wherein: the framework monomer is also provided with a fixed seat for mounting each pair of pneumatic muscle interfaces and air pipe interfaces in the circumferential direction, and the sealing fixed interface and the inflation interface are respectively arranged on the opposite surfaces of the fixed seats; an air passage is arranged in the fixed seat, and the air pipe connector is communicated with the inflation connector through the air passage.

4. A rigid-flexible coupled robot arm according to any one of claims 1-3, wherein: each group of pneumatic muscles comprises four pneumatic muscles, and the four pneumatic muscles are distributed in the circumferential direction of the inner framework at equal angles.

5. The rigid-flexible coupled robotic arm of claim 1, wherein: the pneumatic muscle is made of silica gel.

6. A rigid-flexible coupled robot, comprising: comprising a rigid-flexible coupled robot arm according to any of claims 1-5.