CN112498512B

CN112498512B - Variable-structure robot based on Bernoulli chuck

Info

Publication number: CN112498512B
Application number: CN202011193064.XA
Authority: CN
Inventors: 陈燕虎; 刘斯悦; 杨灿军; 夏庆超
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2020-10-30
Filing date: 2020-10-30
Publication date: 2022-07-05
Anticipated expiration: 2040-10-30
Also published as: CN112498512A

Abstract

The invention relates to a variable-structure robot based on Bernoulli chucks, and belongs to the technical field of underwater robots. Comprises a machine body and a Bernoulli chuck arranged on the machine body; a front mechanical arm and a rear mechanical arm are respectively arranged on two sides of the machine body, and the Bernoulli chucks are arranged on the front mechanical arm and the rear mechanical arm; the front mechanical arm comprises a front upper arm, a front lower arm, a first driver for driving the front upper arm to rotate around the Y axis and a second driver for driving the front lower arm to rotate around the X axis; the Bernoulli sucker can be movably arranged on the front lower arm in a way of rotating around the Z axis; the rear mechanical arm comprises a rear upper arm and a third driver for driving the rear upper arm to rotate around the X axis; the Bernoulli sucker can be movably arranged on the rear upper arm in a way of rotating around the Z axis. The variable structure of the robot is realized through the degrees of freedom of the front mechanical arm and the rear mechanical arm, and the robot is suitable for different working states. Meanwhile, the functions of Bernoulli sucker distance propulsion and adsorption are combined, so that the double-mode switching of robot cruising and wall climbing can be realized, and the redundancy of the whole structure is reduced.

Description

Variable-structure robot based on Bernoulli chuck

Technical Field

The invention relates to the technical field of underwater robots, in particular to a variable-structure robot based on Bernoulli suckers.

Background

With the continuous development of the robot technology, unmanned devices such as four-rotor aircrafts and underwater submerging devices gradually replace manpower, and perform mechanical and high-risk operations such as high-altitude inspection, deep water exploration and equipment maintenance in various dangerous areas. However, the above-mentioned part of the work types have higher precision requirements, for example, the execution equipment can uniformly traverse the target area when the work requirements such as flaw detection of the pile legs of the offshore engineering platform and rust removal and paint spraying of the hull surface are met, otherwise, the work effect is affected and potential safety hazards are urged to be generated; the underwater unmanned underwater vehicle is difficult to avoid wave interference in the operation process, and the machine body shaking caused by the interference inevitably reduces the operation precision and even causes collision loss. Therefore, the key to achieving high quality robotic work is to improve its motion stability under external disturbances.

In recent years, research results on motion stability of four-rotor aircraft and underwater vehicles are emerging, and mainly include two types: one is to develop a motion control algorithm based on sensors such as an Inertial Measurement Unit (IMU) or a pressure gauge, i.e., to compensate at the moment when the robot is disturbed, so that the robot returns to the original position; the other type is that a suction device is arranged on the robot to realize stable suction or wall climbing movement. However, both of the above approaches have certain drawbacks: the technical threshold of the algorithm is high, and the algorithm is difficult to deal with severely disordered environments; the adsorption device can generally provide enough adsorption force for the robot, but the introduction of a new mechanism increases the complexity of the robot and is not beneficial to application in an actual engineering environment.

The invention patent document with publication number CN108556949A discloses a magnetic multi-foot wall-climbing robot, which combines mechanical leg obstacle-crossing and wheel-type motion, and aims to overcome the defect of pure wheel-type or crawler-type wall-climbing robot in obstacle-crossing capability. The tail ends of the mechanical legs are provided with electromagnets which can be adsorbed on the surface of a ferromagnetic material, so that the robot is mainly used for detecting and cleaning the surface of a ship body. However, it is obvious that electromagnetic adsorption is only suitable for ferromagnetic materials, and cannot be used for non-ferromagnetic materials such as concrete, so that the robot has certain limitation in application scenes.

The invention patent document with publication number CN106428484A discloses a self-adaptive multi-legged underwater robot for offshore oil development, which consists of an ROV body and a multi-legged mechanism; the multi-legged mechanism has 6 legs, each leg has 5 degrees of freedom; the sole is sucking disc formula structure, and the sucking disc rotates 90 degrees and can be used for wheeled roll, is suitable for different operating modes through the conversion of wheel foot. However, it can be seen that the robot mechanism is redundant, resulting in complex control and high failure probability.

Disclosure of Invention

The invention aims to provide a variable-structure robot based on a Bernoulli chuck, wherein the chuck and a propeller of the robot are arranged on a mechanical arm with a plurality of degrees of freedom, and can be changed into corresponding postures when different tasks are executed, so that the redundancy of mechanisms is reduced.

In order to achieve the aim, the variable structure robot based on the Bernoulli chuck comprises a machine body and the Bernoulli chuck arranged on the machine body; a front mechanical arm and a rear mechanical arm are respectively arranged on two sides of the machine body, and the Bernoulli chuck is mounted on the front mechanical arm and the rear mechanical arm;

the front mechanical arm comprises a front upper arm, a front lower arm, a first driver for driving the front upper arm to rotate around a Y axis, and a second driver for driving the front lower arm to rotate around an X axis; the Bernoulli sucker can be movably arranged on the front lower arm in a rotating mode around the Y axis;

the rear mechanical arm comprises a rear upper arm and a third driver for driving the rear upper arm to rotate around the X axis; the Bernoulli chuck can be movably arranged on the rear upper arm in a rotating mode around the Y axis.

In the technical scheme, the variable structure of the robot is realized through the degrees of freedom of the front mechanical arm and the rear mechanical arm, and the robot is suitable for different working states. Meanwhile, the combination of the Bernoulli chuck with the functions of propulsion and adsorption can realize the dual-mode switching of the robot during cruising and wall climbing, reduce the redundancy of the whole structure, improve the flexible movement capacity and stable adsorption capacity of the robot, and perform fine operation in high-risk environment.

Optionally, in one embodiment, the bernoulli chuck is mounted on the front lower arm or the rear upper arm by a torsion spring.

Optionally, in an embodiment, the bernoulli chuck includes an adsorption duct and a flexible adsorption plate disposed at a bottom end of the adsorption duct, the upper end of the adsorption duct is provided with a screw propeller, and an adsorption surface of the flexible adsorption plate is provided with a support structure for generating a gap.

Optionally, in an embodiment, the support mechanism is a fan-shaped support column arranged at intervals on the adsorption surface of the flexible adsorption plate.

Optionally, in an embodiment, the screw propeller includes a barrel body adapted to the adsorption duct and a propeller disposed in the barrel body, and the propeller has forward and reverse rotation functions.

Optionally, in an embodiment, the front lower arm and the rear upper arm are provided with flow guide channels adapted to the adsorption duct of the bernoulli chuck, and the side edges of the flow guide channels are provided with flow guide holes.

Optionally, in an embodiment, the front lower arm and the rear upper arm are provided with a buoyancy material mounting groove.

Optionally, in an embodiment, the first driver, the second driver, and the third driver are all steering engines.

Optionally, in one embodiment, the body is provided with a sensor, a cable socket, and front and rear arm fixing plates.

Optionally, in an embodiment, the sensor is a camera or an ultrasonic flaw detector. And can also be connected with execution equipment such as a water gun or a paint spray gun.

Compared with the prior art, the invention has the advantages that:

the sucker of the variable-structure robot can provide larger adsorption force than vacuum adsorption and pure propeller thrust adsorption, has wider application range than electromagnetic adsorption and vacuum adsorption, has the function of a normal propeller, greatly reduces the redundancy of a mechanism, improves the applicability of the sucker, and is a development direction of future high-altitude and underwater fine operation. The design of the variable structure and the self-adaptive joint reduces the redundancy of the mechanism, improves the adaptability of the wall-climbing robot on multi-material special-shaped curved surfaces, and provides a solution for the operation of the robot in narrow and complex spaces such as sunken ships and the like. Meanwhile, the raw materials and parts used by the invention are easy to obtain, and the invention is convenient to manufacture and install, thereby providing convenience for large-scale manufacture and engineering application.

Drawings

FIG. 1 is a schematic overall structure diagram of a variable structure robot based on Bernoulli chucks in an embodiment of the invention;

FIG. 2 is a schematic diagram of a Bernoulli chuck in an embodiment of the invention;

FIG. 3 is an exploded view of a Bernoulli chuck in an embodiment of the invention;

FIG. 4 is an elevation isometric view of a Bernoulli chuck in an embodiment of the invention;

FIG. 5 is a schematic view of a Bernoulli chuck attached to a flat wall surface under the Bernoulli effect in an embodiment of the invention;

FIG. 6 is an exploded view of a variable geometry Bernoulli chuck based robot in accordance with an embodiment of the present invention;

FIG. 7 is a schematic view of a front robotic arm according to an embodiment of the present invention;

FIG. 8 is a schematic view of the rear robot arm in an embodiment of the present invention;

FIG. 9 is a schematic view of a variable geometry Bernoulli chuck based robot in a cruise mode in accordance with an embodiment of the present invention;

FIG. 10 is a schematic diagram of a variable structure robot based on a Bernoulli chuck attached to a curved surface in an embodiment of the invention;

FIG. 11 illustrates an underwater operation mode of a variable structure robot based on Bernoulli chucks in an embodiment of the present invention;

FIG. 12 is a gait of a variable geometry robot based on Bernoulli chucks moving on a wall surface in an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described with reference to the following embodiments and accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived by a person skilled in the art from the described embodiments without any inventive step, are within the scope of protection of the invention.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of the word "comprise" or "comprises", and the like, in the context of this application, is intended to mean that the elements or items listed before that word, in addition to those listed after that word, do not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

Examples

Referring to fig. 1, the variable-structure robot based on bernoulli chucks in the present embodiment includes a main body 100, a front robot arm 200, a rear robot arm 300, and bernoulli chucks 400 provided on the front robot arm 200 and the rear robot arm 300.

Referring to fig. 6 and 9, the body 100 is provided with a sensor 101, a cable socket 102, a front arm fixing plate 103, and a rear arm fixing plate 104. The sensor 101 may be a monitoring device such as a camera, a detection device such as an ultrasonic flaw detector, or a cleaning device such as a water gun. The cable socket 102 is connected to the power line, and the power line simultaneously carries communication signals, so that the weight of the cable can be reduced. The front arm fixing plate 103 and the rear arm fixing plate 104 are integrated with the shell of the body 100 and are made of plastic through one-step molding.

Referring to fig. 6 and 7, the front mechanical arm 200 includes a front upper arm 201, a steering gear 01 fixedly connected in the front upper arm 201, a front lower arm 202, a steering gear 02 fixedly connected in the front lower arm 202, a torsion spring 203, and a suction cup fixing plate 204. The front upper arm 201 is fixedly connected with the front lower arm 202 through a steering engine 02 in the front lower arm 202; the bernoulli chuck 400 is fixedly connected to the front lower arm 202 via a chuck fixing plate 204 and a torsion spring 203. The surface of the front lower arm 202 is provided with a buoyancy material mounting groove 2021, and buoyancy materials such as foam can be arranged in an underwater environment. The front lower arm 202 is further provided with a flow guide hole 2022 and a flow guide way 2023, which can reduce the weight of the robot and does not block the fluid movement. The torsion spring 203 is a passive element, so that the bernoulli chuck 400 can adapt to the irregular curved surface and can automatically recover without interference. The front mechanical arm 200 is connected with a forearm fixing plate 103 through a steering engine 01 in a front upper arm 201. The front mechanical arm 200 has three degrees of freedom relative to the machine body, and the front upper arm 201 is driven by a steering engine 01 in the front upper arm 201 to rotate around the Y axis, the front lower arm 202 is driven by a steering engine 02 in the front lower arm 202 to rotate around the X axis, and the Bernoulli suction cup 400 rotates around the Y axis through a torsion spring 203 arranged on the front lower arm 202.

Referring to fig. 6 and 8, the rear mechanical arm 300 includes a rear upper arm 301, a steering gear 03 fixedly connected in the rear upper arm 301, a suction cup fixing plate 302 and a torsion spring 303. The Bernoulli chuck 400 is fixedly connected with the rear upper arm 301 through the chuck fixing plate 302 and the torsion spring 303. The surface of the rear upper arm 301 is provided with a buoyancy material mounting groove 3011, and buoyancy materials such as foam can be arranged in an underwater environment. The rear upper arm 301 is further provided with a flow guide hole 3012 and a flow guide way 3013, so that the weight of the robot can be reduced, and fluid movement is not hindered. The torsion spring 303 is a passive element, so that the bernoulli chuck 400 can adapt to the irregular curved surface and can automatically recover without interference. The rear mechanical arm 300 is connected with the rear arm fixing plate 104 through a steering engine 03 in the rear upper arm 301. The rear mechanical arm 300 has two degrees of freedom with respect to the body 100, the rear upper arm 301 is driven to rotate about the X-axis by the steering engine 03 in the rear upper arm 301, and the bernoulli chuck 400 rotates about the Y-axis by the torsion spring 303 mounted on the rear upper arm 301.

Referring to fig. 2 to 4, the bernoulli chuck 400 includes an adsorbing duct 401 and a flexible adsorbing and acting plate 402 disposed at the bottom end of the adsorbing duct 401, a screw 403 is disposed at the upper end of the adsorbing duct 401, a supporting structure for generating a gap is disposed on the adsorbing surface of the flexible adsorbing and acting plate 402, and the supporting structure of this embodiment is fan-shaped struts 404 disposed at intervals on the adsorbing surface of the flexible adsorbing and acting plate 402. The flexible adsorption plate 402 can adapt to rough surfaces because the rough slot walls do not greatly affect the flow rate of the high-velocity fluid; in order to adapt to large-curvature adsorption scenes such as platform pile legs and pipelines, the flexible adsorption plate material of the embodiment is a raw material easy to obtain such as silica gel, so that the sucker can cover the adsorption surface as much as possible when the sucker plays a role, and the adsorption area is increased.

The auger 403 comprises a cylinder 4031 adapted to the suction duct 401 and a propeller 4032 arranged inside the cylinder 4031, the propeller 4032 having a forward rotation and a reverse rotation function. Under the action of the propeller 403, the bernoulli chuck 400 can be automatically close to the wall surface for adsorption, a gap is generated by the fan-shaped strut 404, the equilibrium state of adsorption and repulsion is achieved, and when the propeller 4032 rotates reversely, the propulsion function is realized.

Referring to fig. 5, the bernoulli chuck 400 adheres to a flat wall 001 under the dual action of thrust and suction. Due to the close adsorption, the flexible adsorption plate 402 deforms and completely adheres to the wall 001. At this time, the fluid flows into the adsorption duct 401 through the slit flow channels between the fan-shaped pillars 404 on the bottom surface of the flexible adsorption plate 402, and flows in the direction of the arrow in the figure. When the bernoulli chuck 400 needs to be desorbed, the bernoulli chuck 400 can be released without hindrance by simply stalling or reversing the propeller 4032. Experimental results show that the addition of the flexible adsorption plate 402 does not have obvious influence on the propelling function of the propeller.

Referring to fig. 9, when the robot is in a cruising state, each steering engine can be controlled to drive two front mechanical arms 200 and two rear mechanical arms 300 to the postures shown in the figure. In this state, the front robotic arm 200 remains stationary and the augers 403 within the respective bernoulli chucks 400 provide a propulsive force forward along the fuselage 100; the rear mechanical arm 300 can be driven by a steering engine to swing so as to provide pitching propulsive force; when the robot needs to turn, only the rotating speeds of the propellers on the left side and the right side of the robot body need to be adjusted.

Referring to fig. 10, the bernoulli chucks 400 at the ends of the four arms of the robot are all fixed to torsion springs, and when the rigidity of the torsion springs is appropriate, the four bernoulli chucks 400 of the robot can adapt to quite complicated irregular curved surfaces. Fig. 10 shows a state where the robot is attracted to the arc-shaped wall surface 002.

Referring to fig. 11, the robot arm has multiple degrees of freedom to move laterally like a crab. Meanwhile, the flexible Bernoulli chuck 400 still has excellent effects on rough curved surfaces and special-shaped curved surfaces, so that stable adsorption and wall surface crawling without slipping can be realized, and further, fine special operation tasks such as scanning and the like can be executed.

Referring to fig. 12, taking the underwater vehicle as an example: the robot launches water in a cruising posture and goes to a target operation area in a remote control state; after approaching the target area, the robot changes to an adsorption posture and gradually approaches to a top wall surface 003 (such as a large diversion tunnel) under the action of a propeller until the robot is attached and a Bernoulli adsorption state is established; if the propeller is to be attached to the sidewall 004 (such as a dam), the propeller needs to be controlled to change the attitude of the body, and the operations are repeated subsequently.

Claims

1. A variable structure robot based on Bernoulli chucks comprises a machine body and the Bernoulli chucks arranged on the machine body; the Bernoulli chuck is characterized in that a front mechanical arm and a rear mechanical arm are respectively arranged on two sides of the machine body, and the Bernoulli chuck is mounted on the front mechanical arm and the rear mechanical arm;

the rear mechanical arm comprises a rear upper arm and a third driver for driving the rear upper arm to rotate around the X axis; the Bernoulli sucker can be movably arranged on the rear upper arm in a rotating way around the Y axis;

the Bernoulli sucker comprises an adsorption duct and a flexible adsorption action plate arranged at the bottom end of the adsorption duct, wherein the upper end of the adsorption duct is provided with a spiral propeller, and a support structure for generating a gap is arranged on the adsorption surface of the flexible adsorption action plate;

the spiral propeller comprises a cylinder body matched with the adsorption duct and a propeller arranged in the cylinder body, and the propeller has the functions of positive rotation and reverse rotation.

2. A bernoulli chuck based variable geometry robot as claimed in claim 1 wherein the bernoulli chuck is mounted on the front lower arm or rear upper arm by a torsion spring.

3. The bernoulli chuck-based variable geometry robot of claim 1 wherein the support structure is a sector shaped post spaced on the suction surface of the flexible suction effect plate.

4. The variable-structure robot based on the Bernoulli chuck according to claim 1, wherein flow guide channels adapted to the adsorption ducts of the Bernoulli chuck are arranged on the front lower arm and the rear upper arm, and flow guide holes are arranged on the side edges of the flow guide channels.

5. The variable geometry bernoulli chuck-based robot of claim 1 wherein said front lower arm and said rear upper arm are provided with buoyant material mounting slots.

6. The variable-structure robot based on the Bernoulli chuck of claim 1, wherein the first driver, the second driver and the third driver are all steering engines.

7. The bernoulli chuck-based variable geometry robot of claim 1 wherein the body has sensors, cable sockets, and front and rear arm mounting plates.

8. The variable-structure robot based on the Bernoulli chuck of claim 7, wherein the sensor is a camera or an ultrasonic flaw detector.