CN113803565A - Software pipeline detection robot based on intelligent material driving - Google Patents

Software pipeline detection robot based on intelligent material driving Download PDF

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Publication number
CN113803565A
CN113803565A CN202111116932.9A CN202111116932A CN113803565A CN 113803565 A CN113803565 A CN 113803565A CN 202111116932 A CN202111116932 A CN 202111116932A CN 113803565 A CN113803565 A CN 113803565A
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China
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anchoring
dielectric elastomer
unit
voltage
driver
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CN202111116932.9A
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CN113803565B (en
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赵慧婵
汤超
杜伯源
姜淞文
刘辛军
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Tsinghua University
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Tsinghua University
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/26Pigs or moles, i.e. devices movable in a pipe or conduit with or without self-contained propulsion means
    • F16L55/28Constructional aspects
    • F16L55/30Constructional aspects of the propulsion means, e.g. towed by cables
    • F16L55/32Constructional aspects of the propulsion means, e.g. towed by cables being self-contained
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L55/00Devices or appurtenances for use in, or in connection with, pipes or pipe systems
    • F16L55/26Pigs or moles, i.e. devices movable in a pipe or conduit with or without self-contained propulsion means
    • F16L55/28Constructional aspects
    • F16L55/40Constructional aspects of the body
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L2101/00Uses or applications of pigs or moles
    • F16L2101/30Inspecting, measuring or testing

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Manipulator (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)

Abstract

The invention discloses a soft pipeline detection robot based on intelligent material driving, which comprises an extension unit and two anchoring units, wherein the extension unit comprises a columnar first dielectric elastomer driver, and the first dielectric elastomer driver axially extends after voltage is applied; one of the two anchoring units is a front anchoring unit and the other anchoring unit is a rear anchoring unit, and the two anchoring units are respectively positioned at two axial ends of the extension unit and are coaxially connected with the extension unit in a butt joint manner; each anchoring unit comprises a columnar second dielectric elastomer driver and two flexible hinges, and the tail ends of a plurality of branched chains of the two flexible hinges are correspondingly adhered and connected one by one to form anchoring feet; when the second dielectric elastomer driver applies voltage, the second dielectric elastomer driver axially extends to reduce the radial dimension of the anchoring unit. The invention has simple structure, is easy to miniaturize as a whole and can realize quick movement in a narrow pipeline.

Description

Software pipeline detection robot based on intelligent material driving
Technical Field
The invention relates to the technical field of pipeline detection robots, in particular to a soft pipeline detection robot based on intelligent material driving.
Background
In recent years, with the development of microelectronics, microsensors, precision processing and new materials, a light and small mobile robot, which is an important branch of the robot field, has been developed, and among them, a software robot with features of flexibility, safety, compatibility, etc. is typically used. The soft robot has small size, light weight and flexible motion, so that the soft robot has wide application prospect in the fields of military reconnaissance, large-scale engine detection, disaster rescue, medical engineering and the like. In a plurality of application fields of the soft robot, the characteristic of soft large deformation is particularly suitable for detecting pipelines or natural cavities of human bodies. The diameter of the pipeline of some large-scale aircraft engines is only a few millimeters, and the traditional robot with a driving mode of a motor and a gear box is difficult to miniaturize, so that the robot suitable for miniature pipeline detection is extremely difficult to design and manufacture.
In recent years, a new driving technology applied to a pipe moving robot has been developed in large quantities. According to different driving principles, the currently developed novel driving technologies mainly include piezoelectric material-based driving, shape memory alloy-based driving, pneumatic drivers and the like. Shape memory alloys have a slow response speed, are fragile in piezoelectric materials, and have complicated shapes and high difficulty in processing and manufacturing, and pneumatic driving is generally limited by a huge external air source and air path system.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a soft pipeline detection robot based on intelligent material driving, which has a simple structure, is easy to miniaturize as a whole, can realize rapid movement in a narrow pipeline, and can meet the requirement of environment detection of a complex curved pipeline.
According to the embodiment of the invention, the soft pipeline detection robot based on intelligent material driving comprises:
an elongated unit comprising a first dielectric elastomer driver in the shape of a cylinder that axially elongates upon application of a voltage;
the two anchoring units are respectively positioned at the two axial ends of the elongation unit and are coaxially connected with the elongation unit in a butt joint manner; each anchoring unit comprises a columnar second dielectric elastomer driver and two flexible hinges, each flexible hinge comprises a base and a plurality of branched chains, the branched chains are distributed around the periphery of the base in an array mode, each branched chain comprises a branched chain main body and a branched chain tail end, flexible connection is adopted between one end of each branched chain main body and the periphery of the base and between the other end of each branched chain main body and one end of each branched chain tail end, the bases of the two flexible hinges are respectively connected with the two axial ends of the second dielectric elastomer driver in a one-to-one correspondence mode, the branched chain tail ends of the two flexible hinges are connected in a one-to-one correspondence mode in a sticking mode to form anchoring feet, and the branched chains of the two flexible hinges and the outer periphery of the second dielectric elastomer driver are arranged in an acute angle mode; when the second dielectric elastomer driver applies voltage, the second dielectric elastomer driver axially extends to enable the radial dimension of the anchoring unit to be reduced;
when the intelligent material drive-based soft pipeline detection robot works, after the intelligent material drive-based soft pipeline detection robot is placed in a pipeline, because the initial diameters of the two anchoring units are larger than the inner diameter of the pipeline, the two anchoring units can be placed in the pipeline after being pre-compressed in the radial direction and anchored on the inner wall of the pipeline through the anchoring feet, pre-tightening force can be generated under the action of the elastic force of the second dielectric elastomer drivers of the two anchoring units, the pre-tightening force is reduced after the front anchoring unit applies voltage, and the extension unit extends axially after applying voltage, so that the intelligent material drive-based soft pipeline detection robot extends forwards for a distance, the front anchoring unit is powered off to recover the self-anchoring force, and the intelligent material drive-based soft pipeline detection robot is locked in the extending distance, and the rear anchoring unit starts to apply voltage to reduce the self anchoring force, the extension unit recovers length under the action of elastic force after power failure and drives the rear anchoring unit to advance, so that the soft pipeline detection robot based on intelligent material driving realizes advancing motion under the coordination of the two anchoring units and the extension unit.
According to the soft pipeline detection robot based on intelligent material driving, on one hand, a three-section structure form of the extension unit, the front anchoring unit and the rear anchoring unit is adopted, wherein the extension unit, the front anchoring unit and the rear anchoring unit are all driven based on the dielectric elastomer material, the structure is soft, impact resistance is realized, environmental adaptability is good, the requirement of environment detection of various complex bent pipelines is met, the dielectric elastomer material is high in electrical response frequency, large in deformation and high in electromechanical conversion efficiency, and rapid movement in narrow pipelines can be realized; on the other hand, the soft pipeline detection robot based on the intelligent material drive has the advantages of simple structure, convenience in manufacturing, easiness in miniaturization of the whole robot, capability of meeting the requirements of sub-centimeter-level pipeline detection and wide application prospect.
According to an embodiment of the present invention, the extension unit further includes two first connectors respectively embedded with first magnets and two concentric structural members respectively embedded with second magnets, the two first connectors are respectively and correspondingly fixed at two axial ends of the first dielectric elastomer driver, and the second magnets of the two concentric structural members are connected with the first magnets of the two first connectors in an attracting manner; each anchoring unit further comprises a second connecting piece embedded with a third magnet, and the second connecting piece is fixed on the base of one of the two flexible hinges of the anchoring unit; the two anchoring units are respectively attracted with the second magnet in the corresponding concentric structural member of the extension unit through the third magnet in the second connecting piece, so that the two anchoring units are respectively connected with the extension unit in a butt joint mode.
According to an embodiment of the present invention, the first dielectric elastomer driver and the second dielectric elastomer driver are respectively cylindrical and respectively wound by a sheet driver, and the sheet driver has a deformation behavior characteristic that a thickness reduction and an area expansion occur under voltage loading.
According to a further embodiment of the present invention, the sheet driver is formed by alternately stacking silicon rubber layers and carbon nanotube electrode layers in sequence.
According to a further embodiment of the present invention, the material of the silicone rubber layer in the first dielectric elastomer driver is formed from a first silicone rubber and a second silicone rubber in a ratio of 1:1, and mixing the components in a ratio of 1.
According to a further embodiment of the present invention, the material of the silicone rubber layer in the second dielectric elastomer driver is formed from a third silicone rubber and a fourth silicone rubber in a ratio of 3: 1, and mixing the components in a ratio of 1.
According to one embodiment of the invention, the surface of the anchoring foot is covered with an anchoring silicone rubber for increasing the friction force.
According to one embodiment of the invention, each flexible hinge is formed by cutting a composite material, the composite material is obtained by hot-pressing a flexible film, an adhesive sheet and a carbon fiber plate, wherein the adhesive sheet and the carbon fiber plate are arranged on two sides of the flexible film, the adhesive sheet is used for bonding and fixing the carbon fiber plate and the flexible film, and hollow parts are arranged on the positions, corresponding to the flexible connection, of the flexible hinge on the adhesive sheet and the carbon fiber plate.
According to one embodiment of the present invention, the voltage applied by the first dielectric elastomer driver is a sine wave signal voltage, and the voltage applied by the second dielectric elastomer drivers of the two anchoring units is a square wave signal.
According to a further embodiment of the present invention, the voltage driving signal phase of the front anchoring unit is 0 °, the voltage driving signal phase of the elongated unit is 270 °, and the voltage driving signal phase of the rear anchoring unit is 180 °.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a schematic structural diagram of a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Fig. 2 is a perspective assembly view of a soft pipeline inspection robot based on smart material driving according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of an anchoring unit in a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a concentric structural member in a soft pipeline detection robot based on intelligent material driving according to an embodiment of the present invention.
Fig. 5 is a schematic structural diagram of a first connecting member in a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Fig. 6 is a schematic structural diagram of a second connecting member in a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Fig. 7 is a schematic diagram of a laser cutting path of a carbon fiber plate in a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Fig. 8 is a schematic processing diagram of a flexible hinge in a soft pipeline detection robot based on smart material driving according to an embodiment of the present invention.
Reference numerals:
software pipeline detection robot 1000 based on intelligent material driving
Extension unit 1
First dielectric elastomer driver 101 first connector 102 first magnet 103
Concentric structural member 104 second magnet 105
Anchoring unit 2
Flexible hinge 202 branch 2021 of second dielectric elastomer actuator 201
Branched end 2024 anchor 2025 of branched body 2023 at base 2022
Second connector 203 third magnet 204 flexible film 205 adhesive sheet 206
Stainless steel hot-pressing die 209 for hollow-out part 208 of carbon fiber plate 207
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
The following describes a soft pipe probing robot 1000 based on smart material driving according to an embodiment of the present invention with reference to fig. 1 to 6, which is used for being placed in a pipe and can move in a narrow pipe.
As shown in fig. 1 to 6, a soft-body pipeline exploring robot 1000 based on smart material driving according to an embodiment of the present invention includes an elongation unit 1 and two anchoring units 2.
The elongation unit 1 comprises a columnar first dielectric elastomer driver 101, and the first dielectric elastomer driver 101 is axially elongated after voltage is applied; one anchoring unit 2 of the two anchoring units 2 is a front anchoring unit and the other anchoring unit 2 is a rear anchoring unit, and the two anchoring units 2 are respectively positioned at two axial ends of the elongation unit 1 and are coaxially connected with the elongation unit 1 in a butt joint manner; each anchor unit 2 comprises a columnar second dielectric elastomer driver 201 and two flexible hinges 202, each flexible hinge 202 comprises a base 2022 and a plurality of branches 2021, the plurality of branches 2021 are distributed around the periphery of the base 2022 in an array, each of the plurality of branches 2021 comprises a branch main body 2023 and a branch end 2024, one end of each branch main body 2023 is flexibly connected with the periphery of the base 2022, the other end of each branch main body 2023 is flexibly connected with one end of each branch end 2024, the base 2022 of each of the two flexible hinges 202 is respectively connected with the two axial ends of the second dielectric elastomer driver 201 in a one-to-one correspondence manner, the plurality of branch ends 2024 of the two flexible hinges 202 are correspondingly connected in a one-to-one manner to form an anchor foot 2025, and the plurality of branches 2021 of the two flexible hinges 202 are arranged at an acute angle with the outer periphery of the second dielectric elastomer driver 201; when the second dielectric elastomer driver 201 is energized, the second dielectric elastomer driver 201 is axially elongated to cause the radial dimension of the anchoring unit 2 to decrease.
Specifically, the elongation unit 1 includes a first dielectric elastomer driver 101 in a columnar shape, and the first dielectric elastomer driver 101 is elongated in the axial direction upon application of a voltage. Here, the first dielectric elastomer driver 101 is in a columnar shape, and may be in a columnar shape, a prismatic shape, or the like, and the first dielectric elastomer driver 101 may be processed by a sheet driver, for example, a columnar dielectric elastomer driver may be wound by a sheet driver; the deformation mechanism of the first dielectric elastomer driver 101 is: the sheet driver can generate deformation behaviors of thickness reduction and area expansion under voltage loading, and therefore the sheet driver can be converted into the deformation behaviors of axial elongation under the voltage loading after being wound into a columnar shape. During the application of voltage to the first dielectric elastomer driver 101, the first dielectric elastomer driver 101 will elongate axially after the application of voltage and will recover its length under the influence of elastic force after the power failure.
One of the two anchor units 2 is a front anchor unit 2 and the other anchor unit 2 is a rear anchor unit, and the two anchor units 2 are respectively located at two axial ends of the elongation unit 1 and are coaxially connected with the elongation unit 1 in a butt joint manner. It will be appreciated that both the front anchoring unit and the rear anchoring unit are used for anchoring with the inner wall of the pipeline, for example, when the rear anchoring unit is anchored with the inner wall of the pipeline and the front anchoring unit is released from anchoring, the first dielectric elastomer driver 101 is extended, then the front anchoring unit is anchored with the inner wall of the pipeline and the rear anchoring unit is released from anchoring with the inner wall of the pipeline and the first dielectric elastomer driver 101 is retracted, thereby realizing the forward movement process of the soft pipeline detection robot 1000 of the present invention. The anchoring unit 2 is coaxially connected with the extension unit 1 in a butt joint manner, which is beneficial to ensuring the concentricity of the pipeline and the soft pipeline detection robot 1000 and further ensuring the anchoring effect of the anchoring unit 2.
Each anchoring unit 2 comprises a second dielectric elastomer driver 201 in the form of a cylinder and two flexible hinges 202. Here, the second dielectric elastomer driver 201 is in a columnar shape, and may be in a columnar shape, a prismatic shape, or the like, and the second dielectric elastomer driver 201 may be processed by a sheet driver, for example, the columnar second dielectric elastomer driver 201 may be wound by a sheet driver; the deformation mechanism of the second dielectric elastomer actuator 201 is: the sheet driver can generate deformation behaviors of thickness reduction and area expansion under voltage loading, and therefore the sheet driver can be converted into the deformation behaviors of axial elongation under the voltage loading after being wound into a columnar shape. The second dielectric elastomer driver 201 can be axially extended when a voltage is applied to the second dielectric elastomer driver 201 and the second dielectric elastomer driver 201 can be axially retracted when the second dielectric elastomer driver 201 is de-energized.
As shown in fig. 3, each flexible hinge 202 includes a base 2022 and a plurality of branches 2021, the plurality of branches 2021 are distributed around the peripheral array of the base 2022 to facilitate uniform radial force transmission; the plurality of branches 2021 each include a branch body 2023 and a branch end 2024, and flexible connections are respectively employed between one end of the branch body 2023 and the periphery of the base portion 2022 and between the other end of the branch body 2023 and one end of the branch end 2024, that is, the base portion 2022, the branch body 2023, and the branch end 2024 of the flexible hinge 202 have certain rigidity and function as a rigid support, and the flexible connection portion of the flexible hinge 202 can enable the branch body 2023 to rotate relative to the base portion 2022 and the branch end 2024 to rotate relative to the branch body 2023. The base portions 2022 of the two flexible hinges 202 are respectively connected to the two axial ends of the second dielectric elastomer driver 201 in a one-to-one correspondence, the ends 2024 of the plurality of branches of the two flexible hinges 202 are respectively connected by adhesion in a one-to-one correspondence to form the anchor feet 2025, and the plurality of branches 2021 of the two flexible hinges 202 and the outer peripheral surface of the second dielectric elastomer driver 201 are arranged in an acute angle. It can be understood that, since the base 2022, the branched body 2023, and the branched end 2024 of the flexible hinge 202 have a certain rigidity and function as a rigid support, and the flexible connection portion of the flexible hinge 202 can enable the branched body 2023 to rotate relative to the base 2022 and enable the branched end 2024 and the branched body 2023 to rotate, the bases 2022 of the two flexible hinges 202 are respectively connected to the two axial ends of the second dielectric elastomer driver 201 in a one-to-one correspondence manner, and the branched ends 2024 of the two flexible hinges 202 are connected to each other in a one-to-one correspondence manner to form the anchoring feet 2025, so that the anchoring unit 2 has a certain rigidity as a whole and also has the impact resistance characteristic of the soft driver.
After the second dielectric elastomer driver 201 applies voltage, the second dielectric elastomer driver 201 extends axially to reduce the radial dimension of the anchoring unit 2, so that the axial output force of the second dielectric elastomer driver 201 can be quickly converted into radial output force under the regulation and control of the voltage, and the radial output force can be regulated only by regulating the voltage. Specifically, when a voltage is applied to the second dielectric elastomer driver 201, the second dielectric elastomer driver 201 elongates and deforms along the axis, so that the plurality of branch bodies 2023 of the two flexible hinges 202 are contracted and deformed toward the outer peripheral surface of the second dielectric elastomer driver 201, and the radial dimension of the anchor unit 2 is reduced. Therefore, when the soft pipeline detection robot 1000 based on the intelligent material drive is placed into a pipeline, the initial diameters of the two anchoring units 2 are required to be slightly larger than the inner diameter of the pipeline, the two anchoring units 2 are pre-compressed in the radial direction and then placed in the pipeline and anchored on the inner wall of the pipeline through the anchoring feet 2025, pre-tightening force can be generated under the action of the elastic force of the second dielectric elastomer drivers 201 of the two anchoring units 2, and the pre-tightening force can be reduced after the voltage is applied to the two anchoring units, so that the anchoring feet 2025 release the anchoring with the inner wall of the pipeline; when the voltage is not applied to the second dielectric elastomer driver 201, the second dielectric elastomer driver 201 axially retracts and deforms, so that the plurality of branched chains 2021 of the two flexible hinges 202 are expanded and deformed away from the outer peripheral surface of the second dielectric elastomer driver 201, the radial size of the anchoring unit 2 is increased, the anchoring feet 2025 are in contact with the inner wall of the pipeline, and the anchoring force of the anchoring unit 2 is recovered, so that the anchoring unit 2 can realize the process of quickly converting the axial output force of the second dielectric elastomer driver 201 into the radial output force under the voltage regulation and control, the regulation and control of the output force can be realized only by regulating whether the voltage is applied or not, and the control is convenient.
When the soft pipeline detection robot 1000 based on intelligent material driving of the embodiment of the invention works, firstly, after the soft pipeline detection robot 1000 based on intelligent material driving is placed in a pipeline, because the initial diameter of the two anchoring units 2 is larger than the inner diameter of the pipeline, the two anchoring units 2 are placed in the pipeline after being pre-compressed in the radial direction and are anchored on the inner wall of the pipeline through the anchoring feet 2025, pre-tightening force is generated under the action of the self elastic force of the second dielectric elastomer drivers 201 of the two anchoring units 2, the self pre-tightening force is reduced after the voltage is applied to the front anchoring unit, meanwhile, the self axial extension of the extension unit 1 is realized after the voltage is applied to the extension unit 1, so that the soft pipeline detection robot 1000 based on intelligent material driving is extended for a distance, and then the front anchoring unit is powered off to recover the self-anchoring force, and the forward extension distance of the soft pipeline detection robot 1000 based on intelligent material driving is locked, and the rear anchoring unit starts to apply voltage to reduce the self anchoring force, the extension unit 1 recovers length under the action of elastic force after power failure and drives the rear anchoring unit to advance, so that the soft pipeline detection robot 1000 based on intelligent material driving realizes advancing motion under the coordination of the two anchoring units 2 and the extension unit 1, and quick movement in a narrow pipeline is realized.
According to the soft pipeline detection robot 1000 based on intelligent material driving provided by the embodiment of the invention, on one hand, a three-section structure form of the extension unit 1, the front anchoring unit 2 and the rear anchoring unit 2 is adopted, wherein the extension unit 1, the front anchoring unit 2 and the rear anchoring unit 2 are all driven based on the dielectric elastomer material, the structure is soft, impact resistance is realized, the environmental adaptability is good, the requirement of environment detection in various complex bent pipelines is met, the dielectric elastomer material has the advantages of high electrical response frequency, large deformation and high electromechanical conversion efficiency, and the rapid movement in narrow pipelines can be realized; on the other hand, the soft pipeline detection robot 1000 based on the intelligent material drive of the embodiment of the invention has the advantages of simple structure, convenient manufacture, easy miniaturization of the whole robot, capability of meeting the requirements of sub-centimeter-level pipeline detection and wide application prospect.
According to an embodiment of the present invention, as shown in fig. 2 and fig. 4 to fig. 6, the extension unit 1 further includes two first connectors 102 embedded with the first magnets 103 respectively and two concentric structural members 104 embedded with the second magnets 105 respectively, the two first connectors 102 are fixed on two axial ends of the first dielectric elastomer driver 101 respectively, and the second magnets 105 of the two concentric structural members 104 are connected with the first magnets 103 of the two first connectors 102 in an attracting manner; each anchoring unit 2 further comprises a second connecting member 203 embedded with a third magnet 204, the second connecting member 203 being fixed to the base 2022 of one 202 of the two flexible hinges 202 of the anchoring unit 2; the two anchoring units 2 are each engaged with the second magnet 105 of the corresponding concentric structural member 104 of the elongation unit 1 by means of the third magnet 204 of the respective second coupling member 203, so that the two anchoring units 2 are each coupled to the elongation unit 1 in a butt joint. It can be understood that the anchoring units 2 and the extension units 1 are connected in a magnetic attraction manner, so that quick combination of different units and quick replacement of damaged units can be realized, for example, when a pipeline with a larger diameter needs to be detected, the anchoring units 2 at two axial ends of the extension unit 1 can be replaced, and the diameter of each anchoring unit 2 is adapted to the diameter of the inner wall of the pipeline under the condition that voltage is not applied; when the anchoring feet 2025 and other structures of the anchoring unit 2 are worn, the anchoring unit 2 can be directly and quickly replaced, and the using effect of the soft pipeline detector robot 1000 is ensured; the concentric structural member 104 mainly functions to maintain the concentricity of the soft pipeline detector robot 1000 and the pipeline, because the soft pipeline detector robot 1000 has a soft overall structure, and the anchoring effect of the anchoring unit 2 is poor under the condition that the concentricity of the soft pipeline detector robot 1000 and the pipeline cannot be ensured.
According to a further embodiment of the present invention, as shown in fig. 1 to 2 and 5, a circular hole is formed on a side wall of the first connecting member 102, the first connecting member 102 is respectively and correspondingly fixed on two axial ends of the first dielectric elastomer driver 101 through epoxy conductive adhesive, two axial end faces of the first dielectric elastomer driver 101 are electrode connection areas, and when assembling, a lead passes through the circular hole and is fixed on the electrode connection area of the first dielectric elastomer driver 101 through conductive adhesive.
According to an embodiment of the present invention, the first dielectric elastomer driver 101 and the second dielectric elastomer driver 201 are respectively cylindrical and respectively wound by a sheet driver, and the sheet driver has a deformation behavior characteristic that a thickness is reduced and an area is expanded under voltage loading. That is, due to this characteristic of the sheet driver, when a voltage is applied to the first dielectric elastomer driver 101 and the second dielectric elastomer driver 201 of the cylinder, the first dielectric elastomer driver 101 and the second dielectric elastomer driver 201 are elongated and deformed along the axis; after the voltage is stopped being applied to the first dielectric elastomer driver 101 and the second dielectric elastomer driver 201 of the cylinder, the first dielectric elastomer driver 101 and the second dielectric elastomer driver 201 can be shortened and deformed along the axis, which is convenient for control. In addition, the dielectric elastomer driver of the cylinder is processed more quickly and conveniently.
According to a further embodiment of the present invention, the sheet-like actuator is formed by alternately stacking silicon rubber layers and carbon nanotube electrode layers in this order. It can be understood that the silicone rubber layer deforms under the loading of voltage, the carbon nanotube electrode layer is used for applying voltage to the silicone rubber layer so as to cause the deformation of the silicone rubber layer, and in addition, the carbon nanotube electrode layer can deform along with the silicone rubber layer.
According to a still further embodiment of the invention, the sheet-like driver is made using a doctor blade coating method: coating a layer of silicon rubber film on a PET film by using a scraper of a film scraping machine, heating, covering a layer of mask plate with a specific shape after the silicon rubber is cured, then transferring a layer of carbon nano tube obtained after vacuum filtration of the single-walled carbon nano tube aqueous solution, removing the mask plate, scraping the film again, and repeating the process until a sheet driver is obtained. When the sheet driver is prepared, a scraper coating method is adopted, so that large-area manufacturing can be realized, the manufacturing is convenient, and the efficiency is high.
According to a still further embodiment of the present invention, the material of the silicone rubber layer in the first dielectric elastomer driver 101 is formed of a first silicone rubber and a second silicone rubber in a ratio of 1:1, the silicon rubber material has softer texture and better elasticity.
Specifically, the first silicone rubber is Ecoflex0030 silicone rubber, and the Ecoflex0030 silicone rubber is platinum-catalyzed silicone rubber (platinum-catalyzed silicones), and comprises part a (component a) and part B (component B), wherein when the silicone rubber is used, the silicone rubber is prepared by mixing the following components in parts by weight of 1:1, mixing part A (component A) and part B (component B) to obtain a first silicon rubber; the second SILICONE rubber was a Dow Corning Sylgard 184. the Dow Corning Sylgard184 includes a SILICONE ELASTOMER CURING AGENT and a SILICONE ELASTOMER BASE (a SILICONE rubber substrate). when used, the second SILICONE rubber was prepared by mixing a 40:1 weight part ratio of SILICONE ELASTOMER BASE and a SILICONE ELASTOMER CURING AGENT.
According to a still further embodiment of the present invention, the material of the silicone rubber layer in the second dielectric elastomer driver 201 is formed of a third silicone rubber and a fourth silicone rubber in a ratio of 3: 1, the silicone rubber layer mixed in this ratio is harder than the silicone rubber layer in the first dielectric elastomer driver 101, and is less likely to deform, which is beneficial to the anchoring unit 2 to achieve a better anchoring effect.
Specifically, the third silicone rubber is French Eken Si Ibeine LSR 4305, the French Eken Si Ibeine LSR 4305 comprises part A (component A) and part B (component B), and when in use, the part A (component A) and the part B (component B) in a weight ratio of 1:1 are mixed to obtain the third silicone rubber; the fourth SILICONE rubber was a Dow Corning Sylgard 184. the Dow Corning Sylgard184 includes SILICONE ELASTOMER CURING AGENT and SILICONE ELASTOMER BASE (Silicone rubber substrate), and when used, the fourth SILICONE rubber was prepared by mixing SILICONE ELASTOMER BASE and SILICONE ELASTOMER CURING AGENT in a weight ratio of 10: 1.
According to one embodiment of the invention, the surface of the anchor foot 2025 is covered with an anchor silicone rubber for increasing friction. Therefore, in the forward movement process of the soft pipeline detection robot 1000 based on intelligent material driving, the anchoring feet 2025 and the inner wall of the pipeline can realize more stable and reliable anchoring, the possibility of relative sliding between the anchoring feet 2025 and the pipeline is reduced, and the moving efficiency is higher, and more stable and reliable operation is realized. Preferably, Sil-poxy silicone rubber of Smooth-on company is adopted as the anchoring silicone rubber, and the use effect is good.
According to an embodiment of the present invention, as shown in fig. 7 and 8, each flexible hinge 202 is formed by cutting a composite material, the composite material is obtained by hot-pressing a flexible film 205, an adhesive sheet 206 and a carbon fiber plate 207, wherein the adhesive sheet 206 and the carbon fiber plate 207 are disposed on both sides of the flexible film 205, the carbon fiber plate 207 and the flexible film 205 are fixed by the adhesive sheet 206 in an adhesive manner, and the adhesive sheet 206 and the carbon fiber plate 207 are provided with hollowed portions 208 at positions corresponding to flexible connections on the flexible hinge 202. It can be understood that the flexible film 205 is provided with the adhesive sheet 206 and the carbon fiber plate 207 on both sides, so that the use strength of the flexible hinge 202 can be increased, and the use effect of the flexible hinge 202 can be ensured. Before hot pressing, the shape of the hollowed-out portion 208 is cut out on the positions corresponding to the adhesive sheet 206 and the carbon fiber plate 207 by using an ultraviolet laser cutting method, the adhesive sheet 206, the flexible film 205 and the carbon fiber plate 207 are laminated in sequence, then a stainless steel hot pressing mold 209 is used for hot pressing to obtain a composite material, and the obtained composite material is subjected to secondary laser cutting according to a set laser cutting path to obtain the flexible hinge 202. Since the flexible film 205 at the hollow portion 208 is not covered by the carbon fiber sheet 207 and the adhesive sheet 206, a flexible connection function between one end of the branched main body 2023 and the periphery of the base portion 2022 and between the other end of the branched main body 2023 and one end of a connection portion of the branched end 2024 is realized. The remaining area of the flexible hinge 202, except for the hollowed-out portion 208, is rigidly supported by the carbon fiber plate 207. Preferably, the carbon fiber plate 207 has a thickness of 100 μm and is effective in use, and the adhesive sheet 206 is made of Pyralux FR0100 available from dupont and has a thickness of 25 μm. The carbon fiber plate 207 comprises three carbon fiber layers, and the carbon fiber plate 207 is formed by sequentially pressing three carbon fiber prepreg tapes in the directions of 0 degree, 90 degrees and 0 degree. The carbon fiber plates 305 on both sides of the flexible film 303 are hot-pressed at a difference of 90 degrees when being hot-pressed together with the flexible film 303 and the adhesive sheet 304, so that the isotropy of the use strength of the flexible hinge 3 can be ensured.
According to one embodiment of the present invention, the voltage applied by the first dielectric elastomer driver 101 is a sine wave signal voltage, and the voltage applied by the second dielectric elastomer drivers 201 of the two anchoring units 2 is a square wave signal. It can be understood that, when a sine wave signal voltage is applied to the first dielectric elastomer driver 101, since the sine wave signal voltage is a voltage that gradually changes continuously, in the process that the first dielectric elastomer driver 101 deforms along with the voltage, the elongation process is gradually performed, so that the soft pipeline detection robot 1000 based on the smart material driving according to the embodiment of the present invention is not easy to slip, and the movement is more efficient. During the application of the sinusoidal voltage to the first dielectric elastomer driver 101, the first dielectric elastomer driver 101 will gradually extend along the axial direction when the applied voltage is gradually increased, and gradually shorten along the axial direction when the applied voltage is gradually decreased, until the voltage is decreased to zero (i.e. after power failure), and the length is restored under the action of the elastic force. The square wave voltage signal is directly applied to the second dielectric elastomer driver 201, so that the second dielectric elastomer driver 201 can generate faster response to realize the rapid anchoring and anchoring removal processes, and further the rapid advance of the soft pipeline detector robot 1000 is favorably realized.
According to a further embodiment of the present invention, the voltage driving signal phase of the front anchoring unit is 0 °, the voltage driving signal phase of the extension unit 1 is 270 °, and the voltage driving signal phase of the rear anchoring unit is 180 °. Thus, the soft pipe inspection robot 1000 based on smart material driving according to the embodiment of the present invention can realize the following processes, first, the voltage applied to the rear anchoring unit is 0, the pre-tightening force of the front anchoring unit is reduced after the voltage is applied to the front anchoring unit, a sinusoidal voltage increased from 0 is applied to the extension unit 1, the extension unit 1 axially extends to extend the soft pipe inspection robot 1000 based on smart material driving by a distance, then, the voltage applied to the front anchoring unit is changed to 0 to restore the anchoring force of the front anchoring unit, the forward-extending distance of the soft pipe inspection robot 1000 based on smart material driving is locked, the voltage is applied to the rear anchoring unit to reduce the anchoring force of the rear anchoring unit and gradually reduce the voltage applied to the extension unit 1, the extension unit 1 recovers its length under the action of the elastic force to drive the rear anchoring unit to advance, thereby enabling the soft pipeline detection robot 1000 based on the intelligent material drive to realize the forward motion under the coordination of the two anchoring units 2 and the extension unit 1.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. A software pipeline detection robot based on intelligent material drive, its characterized in that includes:
an elongated unit comprising a first dielectric elastomer driver in the shape of a cylinder that axially elongates upon application of a voltage;
the two anchoring units are respectively positioned at the two axial ends of the elongation unit and are coaxially connected with the elongation unit in a butt joint manner; each anchoring unit comprises a columnar second dielectric elastomer driver and two flexible hinges, each flexible hinge comprises a base and a plurality of branched chains, the branched chains are distributed around the periphery of the base in an array mode, each branched chain comprises a branched chain main body and a branched chain tail end, flexible connection is adopted between one end of each branched chain main body and the periphery of the base and between the other end of each branched chain main body and one end of each branched chain tail end, the bases of the two flexible hinges are respectively connected with the two axial ends of the second dielectric elastomer driver in a one-to-one correspondence mode, the branched chain tail ends of the two flexible hinges are connected in a one-to-one correspondence mode in a sticking mode to form anchoring feet, and the branched chains of the two flexible hinges and the outer periphery of the second dielectric elastomer driver are arranged in an acute angle mode; when the second dielectric elastomer driver applies voltage, the second dielectric elastomer driver axially extends to enable the radial dimension of the anchoring unit to be reduced;
when the intelligent material drive-based soft pipeline detection robot works, after the intelligent material drive-based soft pipeline detection robot is placed in a pipeline, because the initial diameters of the two anchoring units are larger than the inner diameter of the pipeline, the two anchoring units can be placed in the pipeline after being pre-compressed in the radial direction and anchored on the inner wall of the pipeline through the anchoring feet, pre-tightening force can be generated under the action of the elastic force of the second dielectric elastomer drivers of the two anchoring units, the pre-tightening force is reduced after the front anchoring unit applies voltage, and the extension unit extends axially after applying voltage, so that the intelligent material drive-based soft pipeline detection robot extends forwards for a distance, the front anchoring unit is powered off to recover the self-anchoring force, and the intelligent material drive-based soft pipeline detection robot is locked in the extending distance, and the rear anchoring unit starts to apply voltage to reduce the self anchoring force, the extension unit recovers length under the action of elastic force after power failure and drives the rear anchoring unit to advance, so that the soft pipeline detection robot based on intelligent material driving realizes advancing motion under the coordination of the two anchoring units and the extension unit.
2. The intelligent material drive-based soft pipeline inspection robot according to claim 1, wherein the extension unit further comprises two first connectors embedded with first magnets respectively and two concentric structural members embedded with second magnets respectively, the two first connectors are correspondingly fixed at two axial ends of the first dielectric elastomer driver respectively, and the second magnets of the two concentric structural members are connected with the first magnets of the two first connectors in an attracting manner; each anchoring unit further comprises a second connecting piece embedded with a third magnet, and the second connecting piece is fixed on the base of one of the two flexible hinges of the anchoring unit; the two anchoring units are respectively attracted with the second magnet in the corresponding concentric structural member of the extension unit through the second magnet in the third connecting piece, so that the two anchoring units are respectively connected with the extension unit in a butt joint mode.
3. The smart material drive-based soft body pipeline inspection robot of claim 1,
the first dielectric elastomer driver and the second dielectric elastomer driver are respectively cylindrical and are respectively formed by winding a sheet driver, and the sheet driver has the deformation behavior characteristic that the thickness is reduced and the area is expanded under the voltage loading.
4. The smart material drive-based soft pipeline inspection robot as claimed in claim 3, wherein the sheet driver is formed by alternately stacking silicon rubber layers and carbon nanotube electrode layers in sequence.
5. The smart material drive-based soft pipeline inspection robot as claimed in claim 4, wherein the material of the silicone rubber layer in the first dielectric elastomer drive is formed by a first silicone rubber and a second silicone rubber in a ratio of 1:1, and mixing the components in a ratio of 1.
6. The smart material drive-based soft body pipeline inspection robot of claim 4,
the material of the silicon rubber layer in the second dielectric elastomer driver is formed by a third silicon rubber and a fourth silicon rubber according to the ratio of 3: 1, and mixing the components in a ratio of 1.
7. The smart material drive-based soft pipeline inspection robot according to claim 1, wherein the surface of the anchoring foot is covered with anchoring silicone rubber for increasing friction.
8. The smart material drive-based soft body pipeline inspection robot of claim 1,
each flexible hinge is formed by the cutting of composite material, composite material obtains after flexible film, bonding piece and carbon fiber plate hot pressing, wherein, the both sides of flexible film all are equipped with the bonding piece with the carbon fiber plate, the bonding piece will the carbon fiber plate with flexible film bonds fixedly, the bonding piece with the carbon fiber plate is corresponding to on the flexible hinge the position department of flexonics all sets up fretwork portion.
9. The smart material drive-based soft body pipeline inspection robot of claim 1, wherein the voltage applied by the first dielectric elastomer driver is a sine wave signal voltage and the voltage applied by the second dielectric elastomer drivers of the two anchoring units is a square wave voltage signal.
10. The smart material drive-based soft body duct exploring robot according to claim 9, wherein the voltage drive signal phase of the front anchoring unit is 0 °, the voltage drive signal phase of the elongated unit is 270 °, and the voltage drive signal phase of the rear anchoring unit is 180 °.
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