3D Printing of Flexible Sensing Actuators

Abstract 3D printed flexible sensors have demonstrated great potential for utilization in a variety of different applications including healthcare, environmental sensing, and industrial applications. In recent years, research on this topic has increased to meet low-cost sensing needs due to the development of innovative materials and printing techniques that reduce cost, production time, and enhance the electrical and mechanical properties of the sensors. This paper presents computational simulations of 3D printed flexible sensors, capable of producing an output signal based on the deformation caused by external forces. Two different sensors were designed and tested, working based on a capacitance and resistance change produced by structural deformation. The capacitance sensor was designed maximizing the area of the electrodes and distributing the electrodes over a flexible membrane taking advantage of the produced deformation to reduce the distance between the electrodes. The reduction in the distance between the electrodes increases the capacitance value of the structure. The capacitance sensor was able to almost triple its baseline capacitance when 30 kPa of pressure was applied. The resistance sensor was designed with one continuous flexible conductive element attached to a flexible membrane, taking advantage of the distortion induced in the conductive element. The deformation in the conductive element increases the length of the resistor and causes the resistance value of the structure to increase. The resistance sensor was able to increase its resistance by 1200 ω with 30 kPa of applied pressure. Finally, preliminary results of 3D printed sensors were demonstrated.

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Computationally Efficient Magnetic Position System Calibration

Engineering Proceedings ◽

10.3390/ecsa-7-08219 ◽

2020 ◽

Vol 2 (1) ◽

pp. 72

Author(s):

Stefano Lumetti ◽

Perla Malagò ◽

Dietmar Spitzer ◽

Sigmund Zaruba ◽

Michael Ortner

Keyword(s):

Degrees Of Freedom ◽

Low Cost ◽

Industrial Applications ◽

Position System ◽

Computationally Efficient ◽

System Calibration ◽

Practical Challenge ◽

3D Printed ◽

Cost Efficient ◽

Orientation Systems

Properties such as high resolution, contactless (and thus wear-free) measurement, low power consumption, robustness against temperature and contamination as well as low cost make magnetic position and orientation systems appealing for a large number of industrial applications. Nevertheless, one major practical challenge is their sensitivity to fabrication tolerances. In this work, we propose a novel method for magnetic position system calibration based on the analytical computation of the magnetic field and on the application of an evolutionary optimization algorithm. This scheme enables the calibration of more than 10 degrees of freedom within a few seconds on standard quad-core ×86 processors, and is demonstrated by calibrating a highly cost-efficient 3D-printed 3-axis magnetic joystick.

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A New Approach to Monitoring Rupture Disc Operation

Volume 4: Dynamics, Control and Uncertainty, Parts A and B ◽

10.1115/imece2012-86369 ◽

2012 ◽

Author(s):

Xiuping Mu

Keyword(s):

Low Cost ◽

Sensor Technology ◽

Dynamic Flow ◽

New Approach ◽

Flexible Membrane ◽

Flexible Sensors ◽

Hazardous Environments ◽

Rupture Disc ◽

Status Signals ◽

Flow Detection

Reliable sensors for monitoring rupture disc activation (also known as burst or rupture) are needed in order to provide immediate warning of a ruptured disc resulting from abnormal process overpressure or vacuum conditions. Many rupture discs are operated in harsh and/or hazardous environments, such as high temperature, highly corrosive, or explosive atmospheres. Also for some critical applications rupture discs and accessories with non-fragmentation features are necessary. Conventional or recently emerged sensors are available for burst disc detection, such as generic pressure switches and instruments specifically designed for burst disc detection. However, many of these devices are either mechanically too fragile, economically not practical, or not suitable for critical rupture disc applications. This paper introduces a new approach of monitoring rupture disc activation using flexible membrane sensor technology. Commercially available resistive type flexible sensors were studied and those with good performance in terms of responsive to burst sensing and materials most suitable for harsh environment were prototyped for the development. An algorithm was developed to carry out the signal processing and generate status signals using microcontrollers. With the low cost membrane sensors and increased functionalities and operability of microcontrollers, the method is expected to play an increasingly important role in rupture disc monitoring as well as other dynamic flow detection.

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Pioneering Low-Cost 3D-Printed Transtibial Prosthetics to Serve a Rural Population in Sierra Leone

SSRN Electronic Journal ◽

10.2139/ssrn.3745177 ◽

2020 ◽

Author(s):

Merel van der Stelt ◽

Martin P. Grobusch ◽

Abdul R. Koroma ◽

Marco Papenburg ◽

Ismaila Kebbie ◽

...

Keyword(s):

Sierra Leone ◽

Rural Population ◽

Low Cost ◽

3D Printed

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Pressure Orientation-Dependent Recovery of 3D-Printed PLA Objects with Varying Infill Degree

Polymers ◽

10.3390/polym13081275 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1275 ◽

Cited By ~ 1

Author(s):

Guido Ehrmann ◽

Andrea Ehrmann

Keyword(s):

Shape Memory ◽

Fused Deposition Modeling ◽

Static Load ◽

Shape Memory Polymer ◽

Applied Pressure ◽

Poly Lactic Acid ◽

Fused Deposition ◽

Deposition Modeling ◽

Load Tests ◽

3D Printed

Poly(lactic acid) is not only one of the most often used materials for 3D printing via fused deposition modeling (FDM), but also a shape-memory polymer. This means that objects printed from PLA can, to a certain extent, be deformed and regenerate their original shape automatically when they are heated to a moderate temperature of about 60–100 °C. It is important to note that pure PLA cannot restore broken bonds, so that it is necessary to find structures which can take up large forces by deformation without full breaks. Here we report on the continuation of previous tests on 3D-printed cubes with different infill patterns and degrees, now investigating the influence of the orientation of the applied pressure on the recovery properties. We find that for the applied gyroid pattern, indentation on the front parallel to the layers gives the worst recovery due to nearly full layer separation, while indentation on the front perpendicular to the layers or diagonal gives significantly better results. Pressing from the top, either diagonal or parallel to an edge, interestingly leads to a different residual strain than pressing from front, with indentation on top always firstly leading to an expansion towards the indenter after the first few quasi-static load tests. To quantitatively evaluate these results, new measures are suggested which could be adopted by other groups working on shape-memory polymers.

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UV Inscription and Pressure Induced Long-Period Gratings through 3D Printed Amplitude Masks

Sensors ◽

10.3390/s21061977 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1977

Author(s):

Ricardo Oliveira ◽

Liliana M. Sousa ◽

Ana M. Rocha ◽

Rogério Nogueira ◽

Lúcia Bilro

Keyword(s):

State Of The Art ◽

Low Cost ◽

Resonance Wavelength ◽

Complex Structures ◽

Pressing Method ◽

Long Period ◽

Long Period Gratings ◽

3D Printed ◽

Mechanical Pressing ◽

First Time

In this work, we demonstrate for the first time the capability to inscribe long-period gratings (LPGs) with UV radiation using simple and low cost amplitude masks fabricated with a consumer grade 3D printer. The spectrum obtained for a grating with 690 µm period and 38 mm length presented good quality, showing sharp resonances (i.e., 3 dB bandwidth < 3 nm), low out-of-band loss (~0.2 dB), and dip losses up to 18 dB. Furthermore, the capability to select the resonance wavelength has been demonstrated using different amplitude mask periods. The customization of the masks makes it possible to fabricate gratings with complex structures. Additionally, the simplicity in 3D printing an amplitude mask solves the problem of the lack of amplitude masks on the market and avoids the use of high resolution motorized stages, as is the case of the point-by-point technique. Finally, the 3D printed masks were also used to induce LPGs using the mechanical pressing method. Due to the better resolution of these masks compared to ones described on the state of the art, we were able to induce gratings with higher quality, such as low out-of-band loss (0.6 dB), reduced spectral ripples, and narrow bandwidths (~3 nm).

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BoSL FAL Pump: a small, low-cost, easily constructed, 3D-printed peristaltic pump for sampling of waters

HardwareX ◽

10.1016/j.ohx.2021.e00214 ◽

2021 ◽

pp. e00214

Author(s):

David T. McCarthy ◽

Baiqian Shi ◽

Miao Wang ◽

Stephen Catsamas

Keyword(s):

Low Cost ◽

Peristaltic Pump ◽

3D Printed

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Remote Reflectivity Sensor for Industrial Applications

Sensors ◽

10.3390/s21041301 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1301

Author(s):

Federico Cavedo ◽

Parisa Esmaili ◽

Michele Norgia

Keyword(s):

Low Cost ◽

Cost Effective ◽

Industrial Applications ◽

Interference Immunity ◽

Surface Reflection ◽

Measurement Systems ◽

Digital Detector ◽

Reflected Light ◽

Surface Optical ◽

Diffused Light

A low-cost optical reflectivity sensor is proposed in this paper, able to detect the presence of objects or surface optical properties variations, at a distance of up to 20 m. A collimated laser beam is pulsed at 10 kHz, and a synchronous digital detector coherently measures the back-diffused light collected through a 1-inch biconvex lens. The sensor is a cost-effective solution for punctual measurement of the surface reflection at different distances. To enhance the interference immunity, an algorithm based on a double-side digital baseline restorer is proposed and implemented to accurately detect the amplitude of the reflected light. As results show, the sensor is robust against ambient light and shows a strong sensitivity on a wide reflection range. The capability of the proposed sensor was evaluated experimentally for object detection and recognition, in addition to dedicated measurement systems, like remote encoders or keyphasors, realized far from the object to be measured.

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Using low-cost 3D-printed models of prenatal ultrasonography for visually-impaired expectant persons

Patient Education and Counseling ◽

10.1016/j.pec.2021.02.033 ◽

2021 ◽

Author(s):

Romain Nicot ◽

Edwige Hurteloup ◽

Sébastien Joachim ◽

Charles Druelle ◽

Jean-Marc Levaillant

Keyword(s):

Visually Impaired ◽

Low Cost ◽

Prenatal Ultrasonography ◽

3D Printed

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Microstructured Surface Plasmon Resonance Sensor Based on Inkjet 3D Printing Using Photocurable Resins with Tailored Refractive Index

Polymers ◽

10.3390/polym13152518 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2518

Author(s):

Nunzio Cennamo ◽

Lorena Saitta ◽

Claudio Tosto ◽

Francesco Arcadio ◽

Luigi Zeni ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

3D Printing ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Optical Sensor ◽

Low Cost ◽

3D Print ◽

Spr Sensor ◽

Resonance Sensor ◽

3D Printed

In this work, a novel approach to realize a plasmonic sensor is presented. The proposed optical sensor device is designed, manufactured, and experimentally tested. Two photo-curable resins are used to 3D print a surface plasmon resonance (SPR) sensor. Both numerical and experimental analyses are presented in the paper. The numerical and experimental results confirm that the 3D printed SPR sensor presents performances, in term of figure of merit (FOM), very similar to other SPR sensors made using plastic optical fibers (POFs). For the 3D printed sensor, the measured FOM is 13.6 versus 13.4 for the SPR-POF configuration. The cost analysis shows that the 3D printed SPR sensor can be manufactured at low cost (∼15 €) that is competitive with traditional sensors. The approach presented here allows to realize an innovative SPR sensor showing low-cost, 3D-printing manufacturing free design and the feasibility to be integrated with other optical devices on the same plastic planar support, thus opening undisclosed future for the optical sensor systems.

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Deconstruction of Lignin: From Enzymes to Microorganisms

Molecules ◽

10.3390/molecules26082299 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2299

Author(s):

Jéssica P. Silva ◽

Alonso R. P. Ticona ◽

Pedro R. V. Hamann ◽

Betania F. Quirino ◽

Eliane F. Noronha

Keyword(s):

Microbial Communities ◽

Metabolic Pathways ◽

Low Cost ◽

Direct Analysis ◽

Industrial Applications ◽

Natural Environments ◽

Lignocellulosic Residues ◽

Complementary Techniques ◽

Plant Polymer ◽

Powerful Strategy

Lignocellulosic residues are low-cost abundant feedstocks that can be used for industrial applications. However, their recalcitrance currently makes lignocellulose use limited. In natural environments, microbial communities can completely deconstruct lignocellulose by synergistic action of a set of enzymes and proteins. Microbial degradation of lignin by fungi, important lignin degraders in nature, has been intensively studied. More recently, bacteria have also been described as able to break down lignin, and to have a central role in recycling this plant polymer. Nevertheless, bacterial deconstruction of lignin has not been fully elucidated yet. Direct analysis of environmental samples using metagenomics, metatranscriptomics, and metaproteomics approaches is a powerful strategy to describe/discover enzymes, metabolic pathways, and microorganisms involved in lignin breakdown. Indeed, the use of these complementary techniques leads to a better understanding of the composition, function, and dynamics of microbial communities involved in lignin deconstruction. We focus on omics approaches and their contribution to the discovery of new enzymes and reactions that impact the development of lignin-based bioprocesses.

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