CN108204784B - Displacement sensing system and method based on 3D printing and Flex sensing technology - Google Patents
Displacement sensing system and method based on 3D printing and Flex sensing technology Download PDFInfo
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- CN108204784B CN108204784B CN201810011248.6A CN201810011248A CN108204784B CN 108204784 B CN108204784 B CN 108204784B CN 201810011248 A CN201810011248 A CN 201810011248A CN 108204784 B CN108204784 B CN 108204784B
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- 238000006073 displacement reaction Methods 0.000 title claims abstract description 55
- 238000010146 3D printing Methods 0.000 title claims abstract description 26
- 238000005516 engineering process Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000005452 bending Methods 0.000 claims abstract description 60
- 238000004806 packaging method and process Methods 0.000 claims abstract description 23
- 238000005538 encapsulation Methods 0.000 claims abstract description 8
- 239000000463 material Substances 0.000 claims description 25
- 238000002474 experimental method Methods 0.000 claims description 13
- 238000007639 printing Methods 0.000 claims description 9
- 238000013461 design Methods 0.000 claims description 5
- 238000005259 measurement Methods 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- 238000009795 derivation Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 claims description 3
- 239000002689 soil Substances 0.000 abstract description 4
- 238000012544 monitoring process Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000007405 data analysis Methods 0.000 description 1
- 238000013480 data collection Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y80/00—Products made by additive manufacturing
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- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C17/00—Arrangements for transmitting signals characterised by the use of a wireless electrical link
- G08C17/02—Arrangements for transmitting signals characterised by the use of a wireless electrical link using a radio link
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Length Measuring Devices With Unspecified Measuring Means (AREA)
Abstract
The invention relates to a displacement sensing system based on 3D printing and Flex bending sensing technologies, which comprises a thin plate, a first rod piece, a second rod piece, a box and an encapsulation rod, wherein one end of the first rod piece is connected with the center of the thin plate, the other end of the first rod piece is provided with a hinge, one end of the first rod piece, which is provided with the hinge, is positioned in the box, the second rod piece penetrates through the hinge, and the two ends of the second rod piece are arranged in a groove which is arranged on the box and is in the same plane with the hinge; the hinge is further connected with one end of the packaging rod, the other end of the packaging rod is fixed on the inner wall of the box through the hinge, and the Flex bending sensor is packaged in the packaging rod. The invention also relates to a measuring method of the displacement sensing system. The invention can rapidly measure the displacement of the soil body in geotechnical engineering.
Description
Technical Field
The invention relates to a displacement sensing system, in particular to a displacement sensing system and a displacement sensing method based on 3D printing and Flex bending sensing technologies.
Background
For geotechnical engineering, measuring the displacement of soil is very important, the foundation sometimes needs to measure the settlement of the soil, and whether the construction requirements are met is checked through comparing with specifications; in the side slope aspect, work such as disaster early warning can be carried out through the measurement of displacement. Therefore, it is necessary to develop a sensor that is waterproof, durable, simple, and accurate.
For measuring displacement, besides commercially available sensors, a large number of FBG sensors are developed, and CN 107131836A uses FBG to calculate displacement by measuring earth pressure, so that the method has high accuracy, but the cost may be too high due to too many FBG used, and in addition, if large displacement deformation is encountered, the device may be damaged. In addition, the sensor is connected to a conventional cable, and the inconvenience thereof is not described in detail.
The Flexforce bending sensor is a novel resistance type sensor composed of ultrathin resistance sheets, and compared with a traditional bending sensor, the Flexforce bending sensor is higher in precision, convenient to carry and more convenient for data acquisition, and the advantages are obvious. Due to the light and thin characteristic, the Flexiform bending sensor is easier to fix at a position to be measured through external packaging than the traditional sensor. The sensor is well separated from the outside by the external packaging, so that the sensor is rarely influenced by the environment, and the vertical multipoint synchronous measurement and the multiple and cyclic use can be realized. The Flexiforce bending sensor which has the advantages of light weight, portability, recyclability, difficulty in being influenced by the environment, wireless analog output and the like can be embedded into a material to be measured to perform full-automatic quasi-distributed measurement through packaging. The Flexforce sensor applies the current advanced bending sensing technology, is widely applied to a plurality of research fields such as medicine and mechanics, and is applied to measuring the development condition of deformation or cracks on the surface of a building structure in civil engineering.
Bluetooth technology, a substitute for the standard supporting short-range wireless technology of devices, is used to describe the link condition of short-range radio system between devices, and can be used to communicate between wireless handsets, mobile phones, computers, and other devices. The technology is suitable for short-distance wireless information exchange without wire connection. With the development of computer network wireless technology, the bluetooth alliance has formally introduced the bluetooth core specification 4.0 (called bluetooth smart) in 6.30.2010. Bluetooth is low in power consumption, and simple links can be established quickly. General improvements of version 4.0 include the improvements necessary to advance bluetooth low energy mode, and the generic attribute profile (GATT) and AES-encrypted Security Manager (SM) services. This provides convenience for realizing safe and convenient data transmission.
Disclosure of Invention
The invention aims to provide a displacement sensing system and a displacement sensing method based on 3D printing and Flex bending sensing technologies, which can be used for quickly measuring the displacement of a soil body in geotechnical engineering.
The technical scheme adopted by the invention for solving the technical problems is as follows: the displacement sensing system comprises a thin plate, a first rod piece, a second rod piece, a box and an encapsulation rod, wherein one end of the first rod piece is connected with the center of the thin plate, a hinge is arranged at the other end of the first rod piece, one end of the first rod piece, which is provided with the hinge, is positioned in the box, the second rod piece penetrates through the hinge, and the two ends of the second rod piece are arranged in a groove which is arranged on the box and is in the same plane with the hinge; the hinge is further connected with one end of the packaging rod, the other end of the packaging rod is fixed on the inner wall of the box through the hinge, and the Flex bending sensor is packaged in the packaging rod.
The packaging rod is formed by printing two materials, wherein a seam is arranged in the middle of the material on the upper layer, a groove for mounting the Flex bending sensor is reserved in the middle of the material on the upper layer, and the material on the lower layer is arranged in a full-length mode; the hardness of the material on the upper layer is higher than that of the material on the lower layer.
The Flex bend sensor is directly printed into the reserved slot by 3D printing technology.
The thin plate and the first rod piece are printed into a whole in a 3D printing mode.
Still be provided with the bluetooth transmitter in the box, the bluetooth transmitter with Flex bending sensor wireless connection.
The technical scheme adopted by the invention for solving the technical problems is as follows: the displacement sensing method based on the 3D printing and Flex bending sensing technology is further provided, and the displacement sensing system comprises the following steps:
(1) designing the size of the Flex bending sensor according to a detected object, performing 3D printing according to the design, assembling after printing, finally performing encapsulation protection, and bringing the Flex bending sensor to a detection point;
(2) establishing wireless connection between the data acquisition unit and the data receiving terminal through a wireless module;
(3) the relationship between the rotation angle and the Flex bending sensor data is obtained through calibration experiments: according to a diagram of the index of the Flex bending sensor changing along with time, the relationship between the index of the Flex bending sensor and the angle obtained by a calibration experiment is utilized, and the relationship between the displacement and the angle is found out through geometric derivation, so that the direct relationship between the Flex bending sensor and the displacement is obtained, and the measurement is completed.
The step (3) is specifically as follows:
(31) the length of the packaging rod in the initial state is 2l1The vertical distance between the highest point and the lowest point is l2The initial included angle of the two wings is theta2(ii) a After the Flex bending sensor is installed, a displacement s is applied, and the vertical displacement of the displacement s relative to the seam is much larger, so that the vertical displacement is still l if the vertical displacement is unchanged2The angle becomes theta1Then, then
Then
(32) In the calibration experiment, since only one position of the Flex bending sensor is bent, the index and the angle of the Flex bending sensor meet the functional relation delta theta (f) (x), wherein f (x) is the relation between the rotation angle and the data of the Flex bending sensor obtained through the calibration experiment;
(33) obtaining the relation between the collected data and the displacement:
advantageous effects
Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects: according to the invention, two materials with larger rigidity difference are adopted to package the sensor, the seam is arranged on one side with larger rigidity, and the communicated design is carried out on one side with smaller rigidity, so that the respective performances are fully utilized, the sensor is only bent at the reserved seam, the reliability of data is increased, the traditional hinge bending is replaced, and the printing is more time-saving and labor-saving. The invention also adopts the 3D printing technology for production, the 3D printing technology can realize high precision, the time consumption of manually polishing parts is reduced, and meanwhile, the 3D printing material has the light characteristic, so that the produced material is light and convenient and is convenient for batch transportation.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic view of the structure of the encapsulated rod of the present invention;
FIG. 3 is a schematic diagram of the measurement method of the present invention.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
The embodiment of the invention relates to a displacement sensing system based on 3D printing and Flex bending sensing technologies, which comprises a thin plate 1, a first rod piece 2, a second rod piece 3, a box 4 and an encapsulation rod 5, wherein one end of the first rod piece 2 is connected with the center of the thin plate 1, the other end of the first rod piece is provided with a hinge 6, one end of the first rod piece 2 provided with the hinge 6 is positioned in the box 4, the second rod piece 3 penetrates through the hinge 6, and the two ends of the second rod piece are arranged in a groove, in the same plane with the hinge 6, on the box 4; the hinge 6 is also connected with one end of the packaging rod 5, the other end of the packaging rod 5 is fixed on the inner wall of the box 4 through the hinge 7, and the Flex bending sensor is packaged in the packaging rod 5. And a Bluetooth transmitter is further arranged in the box and is in wireless connection with the Flex bending sensor. In this embodiment, the thin plate and the first rod are printed into a whole in a 3D printing manner.
After most of the whole device is installed, the Flex bending sensor is inserted into a groove reserved in the packaging rod, so that the position of the Flex bending sensor relative to the packaging rod does not move any more after the Flex bending sensor is inserted. When the Flex bending sensor is used, the switch of the Flex bending sensor is turned on, and the Flex bending sensor can enter a working state after wireless connection is successful. Data are collected through the data collection and analysis terminal, the deformation condition of each monitoring point is converted through the change of the data of the sensor, and the displacement of each monitoring point is monitored in real time.
As shown in fig. 2, the packaging rod is formed by printing two materials, wherein a seam is arranged in the middle of the material on the upper layer, a groove for installing the Flex bending sensor is reserved in the middle of the material on the upper layer, and the material on the lower layer is arranged in a full length manner; the hardness of the material on the upper layer is higher than that of the material on the lower layer. Wherein, the Flex bend sensor can be directly printed into the reserved slot through 3D printing technology. Like this, when displacement appears in the left side, the both ends of encapsulation pole just can be fixed and move at same horizontal plane, because Flex bending sensor's characteristic, through adopting the printing of the different materials of two kinds of hardness, the upper strata is the PLA material that the hardness is great (set up the seam in the centre and reserve the slot), and the lower floor is the flexible material that the hardness is littleer (leading to long arranging), prints limit installation Flex bending sensor, makes Flex bending sensor and encapsulation member better become an organic whole, so can only let Flex bending sensor at a bit crooked.
The embodiment of the invention also relates to a displacement sensing method based on the 3D printing and Flex bending sensing technology, and the displacement sensing system comprises the following steps:
the method comprises the following steps: designing and installing:
firstly, the size design of a Flex bending sensor is carried out according to a detected object, the Flex bending sensor mainly comprises the length, the width, the thickness or the radius of each part and the number of components, 3D printing (comprising hinges, thin plates, boxes and various required rod pieces) is carried out according to the design, assembly is carried out after the printing is finished (the Flex bending sensor is packaged in the printing process), and finally, the wireless pressure measuring device is packaged and protected and is taken to a detection point.
Step two: testing the detection system:
and establishing wireless connection between the data acquisition unit and the data receiving terminal through the Bluetooth module, and recording and adjusting the monitoring data by using corresponding driving operation software.
Step three: calibration experiment
And obtaining the relation between the rotation angle and the sensor data through a calibration experiment. According to a graph of the change of the readings of the sensors along with time, the relationship between the readings of the wireless sensors and the angles is obtained by a calibration experiment, and the relationship between the displacement and the angles is found out through simple geometric derivation, so that the direct relationship between the data of the sensors and the displacement is obtained. Therefore, different displacements can be directly calculated through different sensor data.
In the third step, the method for calculating the pressure by using the bending sensor comprises the following steps:
And 3, obtaining the relation between the acquired data and the displacement:
Claims (6)
1. a displacement sensing system based on 3D printing and Flex bending sensing technology comprises a thin plate, a first rod piece, a second rod piece, a box and an encapsulation rod, and is characterized in that one end of the first rod piece is connected with the center of the thin plate, a hinge is arranged at the other end of the first rod piece, one end of the first rod piece, which is provided with the hinge, is located in the box, the second rod piece penetrates through the hinge, and the two ends of the second rod piece are arranged in a groove which is arranged on the box and is in the same plane with the hinge; the hinge is also connected with one end of the packaging rod, the other end of the packaging rod is fixed on the inner wall of the box through the hinge, and a Flex bending sensor is packaged in the packaging rod; the packaging rod is formed by printing two materials, wherein a seam is arranged in the middle of the material on the upper layer, a groove for mounting the Flex bending sensor is reserved in the middle of the material on the upper layer, and the material on the lower layer is arranged in a full-length mode; the hardness of the material on the upper layer is higher than that of the material on the lower layer.
2. The displacement sensing system based on 3D printing and Flex bend sensing technology of claim 1, characterized in that the Flex bend sensor is printed directly into the reserved slot by 3D printing technology.
3. The displacement sensing system based on 3D printing and Flex bend sensing technology as claimed in claim 1, wherein the thin plate and the first rod are printed as one body by means of 3D printing.
4. The displacement sensing system based on 3D printing and Flex bend sensing technology as claimed in claim 1, wherein a Bluetooth transmitter is further arranged in the box, and the Bluetooth transmitter is wirelessly connected with the Flex bend sensor.
5. A displacement sensing method based on 3D printing and Flex bend sensing technology, characterized in that a displacement sensing system according to any of claims 1-4 is used, comprising the following steps:
(1) designing the size of the Flex bending sensor according to a detected object, performing 3D printing according to the design, assembling after printing, finally performing encapsulation protection, and bringing the Flex bending sensor to a detection point;
(2) establishing wireless connection between the data acquisition unit and the data receiving terminal through a wireless module;
(3) the relationship between the rotation angle and the Flex bending sensor data is obtained through calibration experiments: according to a diagram of the index of the Flex bending sensor changing along with time, the relationship between the index of the Flex bending sensor and the angle obtained by a calibration experiment is utilized, and the relationship between the displacement and the angle is found out through geometric derivation, so that the direct relationship between the Flex bending sensor and the displacement is obtained, and the measurement is completed.
6. The displacement sensing method based on 3D printing and Flex bend sensing technology according to claim 5, wherein the step (3) is specifically as follows:
(31) the length of the packaging rod in the initial state is 2l1The vertical distance between the highest point and the lowest point is l2The initial included angle of the two wings is theta2(ii) a After the Flex bending sensor is installed, a displacement s is applied, and the vertical displacement of the displacement s relative to the seam is much larger, so that the vertical displacement is still l if the vertical displacement is unchanged2The angle becomes theta1Then, then
Then
(32) In the calibration experiment, since only one position of the Flex bending sensor is bent, the index and the angle of the Flex bending sensor meet the functional relation delta theta (f) (x), wherein f (x) is the relation between the rotation angle and the data of the Flex bending sensor obtained through the calibration experiment;
(33) obtaining the relation between the collected data and the displacement:
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810011248.6A CN108204784B (en) | 2018-01-05 | 2018-01-05 | Displacement sensing system and method based on 3D printing and Flex sensing technology |
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| CN108204784A CN108204784A (en) | 2018-06-26 |
| CN108204784B true CN108204784B (en) | 2020-04-17 |
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| CN111521149A (en) * | 2020-03-24 | 2020-08-11 | 深圳大学 | Soil settlement monitoring system and monitoring method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101504271A (en) * | 2009-03-11 | 2009-08-12 | 清华大学 | Apparatus for implementing inside displacement transmission and seal of hypertonic pressure model experiment |
| CN101825429A (en) * | 2010-04-24 | 2010-09-08 | 大连理工大学 | Dynamic strain measurement-based large-amplitude rotation angle measurement instrument and using method thereof |
| CN104848779A (en) * | 2015-04-01 | 2015-08-19 | 浙江工业大学 | Embedded type deformation gauge with ultralow elastic modulus and method for assembling the embedded type deformation gauge with ultralow elastic modulus |
| CN107478374A (en) * | 2017-08-28 | 2017-12-15 | 叁陆伍科技服务（深圳）有限公司 | A kind of wireless inclination monitoring system based on FLEX crooked sensories and 3D printing technique |
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2018
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101504271A (en) * | 2009-03-11 | 2009-08-12 | 清华大学 | Apparatus for implementing inside displacement transmission and seal of hypertonic pressure model experiment |
| CN101825429A (en) * | 2010-04-24 | 2010-09-08 | 大连理工大学 | Dynamic strain measurement-based large-amplitude rotation angle measurement instrument and using method thereof |
| CN104848779A (en) * | 2015-04-01 | 2015-08-19 | 浙江工业大学 | Embedded type deformation gauge with ultralow elastic modulus and method for assembling the embedded type deformation gauge with ultralow elastic modulus |
| CN107478374A (en) * | 2017-08-28 | 2017-12-15 | 叁陆伍科技服务（深圳）有限公司 | A kind of wireless inclination monitoring system based on FLEX crooked sensories and 3D printing technique |
Non-Patent Citations (2)
| Title |
|---|
| Full perimeter obstacle contact sensor based on flex sensors;R.Ponticelli et al.;《Sensors and Actuators A: Physical》;20081003;第47卷(第2期);第441-448页 * |
| Mechanical model of flex sensors used to sense finger movements;Giovanni Saggio;《Sensors and Actuators A: Physical》;20121030;第53-58页 * |
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