Pub Date : 2024-07-24DOI: 10.1016/j.ohx.2024.e00563
Frederick Kojo Chaway Acquah, Jeremiah Paul Konadu Takyi, Heather R. Beem
Particle Image Velocimetry (PIV) is considered the gold standard technique for flow visualization. However, its cost (at least tens of thousands of dollars) can prove inhibitive in its standard form. This article presents an alternative design, leveraging off-the-shelf and open-source options for each key component involved: camera, laser module, optical components, tracer particles, and analysis software. Flow visualization is a crucial technique to connect theory to practice in teaching and researching fluid mechanics. Despite the ubiquity of this field within engineering curricula, many undergraduate institutions globally forego utilizing such equipment, given the barriers to setting it up. The availability of this low-cost alternative (∼$500) that can be built in-house offers a path forward. Characterization was done by visualizing the rotational flow generated by a magnetic stirrer in a cylindrical beaker. The velocity magnitude around the stirrer bar measured by the low-cost PIV system was compared to expected values calculated analytically. The percent difference was between 1–2% when the flow stayed two-dimensional but increased as the flow began developing into more of a 3-D flow. Repeatability varied no more than 6% between experiments. This platform holds the potential for reliable replication across institutions broadly.
{"title":"Design and characterization of a low-cost particle image velocimetry system","authors":"Frederick Kojo Chaway Acquah, Jeremiah Paul Konadu Takyi, Heather R. Beem","doi":"10.1016/j.ohx.2024.e00563","DOIUrl":"10.1016/j.ohx.2024.e00563","url":null,"abstract":"<div><p>Particle Image Velocimetry (PIV) is considered the gold standard technique for flow visualization. However, its cost (at least tens of thousands of dollars) can prove inhibitive in its standard form. This article presents an alternative design, leveraging off-the-shelf and open-source options for each key component involved: camera, laser module, optical components, tracer particles, and analysis software. Flow visualization is a crucial technique to connect theory to practice in teaching and researching fluid mechanics. Despite the ubiquity of this field within engineering curricula, many undergraduate institutions globally forego utilizing such equipment, given the barriers to setting it up. The availability of this low-cost alternative (∼$500) that can be built in-house offers a path forward. Characterization was done by visualizing the rotational flow generated by a magnetic stirrer in a cylindrical beaker. The velocity magnitude around the stirrer bar measured by the low-cost PIV system was compared to expected values calculated analytically. The percent difference was between 1–2% when the flow stayed two-dimensional but increased as the flow began developing into more of a 3-D flow. Repeatability varied no more than 6% between experiments. This platform holds the potential for reliable replication across institutions broadly.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00563"},"PeriodicalIF":2.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000579/pdfft?md5=2c5df693befc5699c04626b9ebaa95a0&pid=1-s2.0-S2468067224000579-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141846905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-23DOI: 10.1016/j.ohx.2024.e00564
Filippo Sanfilippo, Martin Økter, Jørgen Dale, Hua Minh Tuan, Muhammad Hamza Zafar, Morten Ottestad
Collaborative robots, or cobots, have become popular due to their ability to safely operate alongside humans in shared environments. These robots use compliant actuators as a key design element to prevent damage during unintended collisions. In prosthetic and orthotic applications, compliant actuators are crucial for ensuring user safety and comfort. However, most compliant cobots for these applications are excessively expensive and complex to construct. Our study introduces an innovative, cost-effective, and sensorised elastic actuator design tailored for prosthetics and orthotics. The design uses a modular approach and leverages 3D printing technology for rapid customisation, enabling efficient and affordable fabrication. Both hardware and software components are open-source, facilitating unrestricted access for students, researchers, and practitioners. Our design supports impedance and admittance control techniques, enhancing the system’s capabilities. Validation results show a standard deviation of 9.67 Nm between calculated and measured torque in impedance control and 0.2563 radians between calculated and measured angles in admittance control. This allows for improved adaptability to varying operational requirements in prosthetics and orthotics. By introducing this educational framework encompassing a low-cost, sensorised elastic actuator design, we aim to address the need for accessible solutions in the field of collaborative robotics for prosthetics and orthotics.
协作机器人(或称 cobots)因其能够在共享环境中与人类一起安全操作而广受欢迎。这些机器人使用顺应性致动器作为关键设计元素,以防止意外碰撞时造成损坏。在假肢和矫形应用中,顺应性致动器对于确保用户的安全性和舒适性至关重要。然而,用于这些应用的大多数顺应型 cobots 造价过于昂贵,构造过于复杂。我们的研究介绍了一种专为假肢和矫形器量身定制的创新型、高性价比和传感器化弹性致动器设计。该设计采用模块化方法,并利用 3D 打印技术进行快速定制,实现了高效、经济的制造。硬件和软件组件都是开源的,便于学生、研究人员和从业人员不受限制地使用。我们的设计支持阻抗和导纳控制技术,增强了系统的功能。验证结果表明,在阻抗控制中,计算扭矩与测量扭矩之间的标准偏差为 9.67 牛米;在导纳控制中,计算角度与测量角度之间的标准偏差为 0.2563 弧度。这样就能更好地适应假肢和矫形器的不同操作要求。通过引入这个包含低成本、传感器化弹性致动器设计的教育框架,我们旨在满足假肢和矫形器协作机器人领域对无障碍解决方案的需求。
{"title":"Open-source design of low-cost sensorised elastic actuators for collaborative prosthetics and orthotics","authors":"Filippo Sanfilippo, Martin Økter, Jørgen Dale, Hua Minh Tuan, Muhammad Hamza Zafar, Morten Ottestad","doi":"10.1016/j.ohx.2024.e00564","DOIUrl":"10.1016/j.ohx.2024.e00564","url":null,"abstract":"<div><p>Collaborative robots, or cobots, have become popular due to their ability to safely operate alongside humans in shared environments. These robots use compliant actuators as a key design element to prevent damage during unintended collisions. In prosthetic and orthotic applications, compliant actuators are crucial for ensuring user safety and comfort. However, most compliant cobots for these applications are excessively expensive and complex to construct. Our study introduces an innovative, cost-effective, and sensorised elastic actuator design tailored for prosthetics and orthotics. The design uses a modular approach and leverages 3D printing technology for rapid customisation, enabling efficient and affordable fabrication. Both hardware and software components are open-source, facilitating unrestricted access for students, researchers, and practitioners. Our design supports impedance and admittance control techniques, enhancing the system’s capabilities. Validation results show a standard deviation of 9.67 Nm between calculated and measured torque in impedance control and 0.2563 radians between calculated and measured angles in admittance control. This allows for improved adaptability to varying operational requirements in prosthetics and orthotics. By introducing this educational framework encompassing a low-cost, sensorised elastic actuator design, we aim to address the need for accessible solutions in the field of collaborative robotics for prosthetics and orthotics.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00564"},"PeriodicalIF":2.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000580/pdfft?md5=188ce0d1dd2fe332ff97f9f77a1b2443&pid=1-s2.0-S2468067224000580-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141846189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-21DOI: 10.1016/j.ohx.2024.e00561
Sanna E. Herwald , Daniel Y. Sze , Daniel B. Ennis , Alexander M. Vezeridis
The primary objective of this research was to design, implement, and validate a programmable open-source pulsatile flow system to cost-effectively simulate vascular flows. We employed an Arduino-compatible microcontroller combined with a motor driver to control a centrifugal direct current (DC) motor pump. The system was programmed to produce pulsatile flows with an arterial pulse waveform. Validation with Doppler ultrasound and flow measurements confirmed that our Arduino-based system successfully replicated arterial vascular flow. The materials are easily accessible, with a total bill of materials as low as $99. This open-source programmable pulsatile pump platform offers superior cost-effectiveness and adaptability relative to commercial offerings.
{"title":"Design and implementation of a cost-effective, open-source, and programmable pulsatile flow system","authors":"Sanna E. Herwald , Daniel Y. Sze , Daniel B. Ennis , Alexander M. Vezeridis","doi":"10.1016/j.ohx.2024.e00561","DOIUrl":"10.1016/j.ohx.2024.e00561","url":null,"abstract":"<div><p>The primary objective of this research was to design, implement, and validate a programmable open-source pulsatile flow system to cost-effectively simulate vascular flows. We employed an Arduino-compatible microcontroller combined with a motor driver to control a centrifugal direct current (DC) motor pump. The system was programmed to produce pulsatile flows with an arterial pulse waveform. Validation with Doppler ultrasound and flow measurements confirmed that our Arduino-based system successfully replicated arterial vascular flow. The materials are easily accessible, with a total bill of materials as low as $99. This open-source programmable pulsatile pump platform offers superior cost-effectiveness and adaptability relative to commercial offerings.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00561"},"PeriodicalIF":2.0,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000555/pdfft?md5=4b5fe92fee0021beb1c8e96e8763f240&pid=1-s2.0-S2468067224000555-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141853878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-17DOI: 10.1016/j.ohx.2024.e00560
Edwin Collado , Sallelis Calderón , Betzaida Cedeño , Olga De León , Miriam Centella , Antony García , Yessica Sáez
In recent years, the escalation of industrial activities has significantly increased natural resource pollution, with air pollution becoming a major cause of diseases affecting living organisms. To address this critical environmental challenge, this study proposes a comprehensive air pollution monitoring system utilizing advanced technological instruments based on the Internet of Things (IoT). The system’s primary objective is to provide precise, rapid, and efficient measurements, enabling detailed examinations of pollutant behaviors and facilitating data dissemination. The system includes a monitoring station equipped with sensors to measure ambient temperature, relative humidity, and concentrations of pollutants such as carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), suspended particles (PM2.5, PM10), and ozone (O3). Additionally, it captures meteorological variables like wind speed, wind direction, and precipitation, allowing a nuanced analysis of their correlation with air pollutants. The collected data are transmitted via the Internet and visualized on a user-friendly platform accessible from any internet-enabled device. A protective case, designed with SolidWorks CAD software and fabricated using 3D printing, was validated through simulations for extreme conditions to ensures the system’s robustness in tropical climates. The cost-effective, low-energy system offers a scalable solution for monitoring air pollution, advancing understanding of pollutant behaviors, and supporting environmental management.
近年来,工业活动的升级大大加剧了自然资源污染,空气污染已成为影响生物体疾病的主要原因。为了应对这一严峻的环境挑战,本研究利用基于物联网(IoT)的先进技术仪器,提出了一种全面的空气污染监测系统。该系统的主要目标是提供精确、快速和高效的测量,从而能够详细检查污染物的行为并促进数据传播。该系统包括一个配备传感器的监测站,用于测量环境温度、相对湿度以及一氧化碳(CO)、二氧化氮(NO2)、二氧化硫(SO2)、悬浮颗粒物(PM2.5、PM10)和臭氧(O3)等污染物的浓度。此外,它还能捕捉风速、风向和降水等气象变量,从而对它们与空气污染物的相关性进行细致分析。收集到的数据通过互联网传输,并在一个用户友好的平台上可视化,任何支持互联网的设备均可访问。利用 SolidWorks CAD 软件设计并使用 3D 打印技术制造的保护壳通过了极端条件下的模拟验证,以确保该系统在热带气候下的坚固性。该系统成本低、能耗低,为监测空气污染、增进对污染物行为的了解和支持环境管理提供了可扩展的解决方案。
{"title":"Open-source Internet of Things (IoT)-based air pollution monitoring system with protective case for tropical environments","authors":"Edwin Collado , Sallelis Calderón , Betzaida Cedeño , Olga De León , Miriam Centella , Antony García , Yessica Sáez","doi":"10.1016/j.ohx.2024.e00560","DOIUrl":"10.1016/j.ohx.2024.e00560","url":null,"abstract":"<div><p>In recent years, the escalation of industrial activities has significantly increased natural resource pollution, with air pollution becoming a major cause of diseases affecting living organisms. To address this critical environmental challenge, this study proposes a comprehensive air pollution monitoring system utilizing advanced technological instruments based on the Internet of Things (IoT). The system’s primary objective is to provide precise, rapid, and efficient measurements, enabling detailed examinations of pollutant behaviors and facilitating data dissemination. The system includes a monitoring station equipped with sensors to measure ambient temperature, relative humidity, and concentrations of pollutants such as carbon monoxide (CO), nitrogen dioxide (NO<sub>2</sub>), sulfur dioxide (SO<sub>2</sub>), suspended particles (PM<sub>2.5</sub>, PM<sub>10</sub>), and ozone (O<sub>3</sub>). Additionally, it captures meteorological variables like wind speed, wind direction, and precipitation, allowing a nuanced analysis of their correlation with air pollutants. The collected data are transmitted via the Internet and visualized on a user-friendly platform accessible from any internet-enabled device. A protective case, designed with SolidWorks CAD software and fabricated using 3D printing, was validated through simulations for extreme conditions to ensures the system’s robustness in tropical climates. The cost-effective, low-energy system offers a scalable solution for monitoring air pollution, advancing understanding of pollutant behaviors, and supporting environmental management.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00560"},"PeriodicalIF":2.0,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000543/pdfft?md5=6fdb41964c8550563234eeb62d733373&pid=1-s2.0-S2468067224000543-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141728656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-14DOI: 10.1016/j.ohx.2024.e00559
Jordan F. Hill, Samuel Jackson, Mia Uluilelata, Samrath Sood, Jaimey A. Clifton, Ella F.S. Guy, J. Geoffrey Chase
Current positive airway pressure devices cost NZ$800-$2500, posing a financial barrier for the estimated 1 billion individuals worldwide with sleep apnea and those researching respiratory diseases. Increasing diagnoses and research interest in the area necessitate a low-cost, easily accessible alternative. Thus, the mePAP, a high-quality, multipurpose, low-cost (∼NZ$250) positive airway pressure device, was designed and prototyped specifically for respiratory disease research, particularly for sleep apnea. The mePAP allows user customization and provides researchers with an affordable tool for testing positive airway pressure algorithms. Unlike typical commercial devices, the mePAP offers adaptability with open-source data collection and easily modifiable software for implementing and analysing different control and diagnostic algorithms. It features three control modes: constant; bilevel; and automatic; and provides pressures from 4 to 20 cmH2O, controlled via a phone app through Wi-Fi, with a mini-sensor added at the mask for increased accuracy. Validation tests showed the mePAP’s performance is comparable to a gold-standard Fisher & Paykel device, with extremely similar output pressures. The mePAP’s low cost enhances accessibility and equity, allowing researchers to test ventilation algorithms for sleep apnea and other respiratory conditions, with all data openly available for analysis. Its adaptability and multiple applications increase its usability and usefulness across various research and clinical settings.
{"title":"Design, manufacture, and control of a low-cost positive airway pressure device","authors":"Jordan F. Hill, Samuel Jackson, Mia Uluilelata, Samrath Sood, Jaimey A. Clifton, Ella F.S. Guy, J. Geoffrey Chase","doi":"10.1016/j.ohx.2024.e00559","DOIUrl":"10.1016/j.ohx.2024.e00559","url":null,"abstract":"<div><p>Current positive airway pressure devices cost NZ$800-$2500, posing a financial barrier for the estimated 1 billion individuals worldwide with sleep apnea and those researching respiratory diseases. Increasing diagnoses and research interest in the area necessitate a low-cost, easily accessible alternative. Thus, the mePAP, a high-quality, multipurpose, low-cost (∼NZ$250) positive airway pressure device, was designed and prototyped specifically for respiratory disease research, particularly for sleep apnea. The mePAP allows user customization and provides researchers with an affordable tool for testing positive airway pressure algorithms. Unlike typical commercial devices, the mePAP offers adaptability with open-source data collection and easily modifiable software for implementing and analysing different control and diagnostic algorithms. It features three control modes: constant; bilevel; and automatic; and provides pressures from 4 to 20 cmH2O, controlled via a phone app through Wi-Fi, with a mini-sensor added at the mask for increased accuracy. Validation tests showed the mePAP’s performance is comparable to a gold-standard Fisher & Paykel device, with extremely similar output pressures. The mePAP’s low cost enhances accessibility and equity, allowing researchers to test ventilation algorithms for sleep apnea and other respiratory conditions, with all data openly available for analysis. Its adaptability and multiple applications increase its usability and usefulness across various research and clinical settings.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00559"},"PeriodicalIF":2.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000531/pdfft?md5=130ec8f76cd631c721efcf941a583181&pid=1-s2.0-S2468067224000531-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-11DOI: 10.1016/j.ohx.2024.e00558
Colin Butler , Emmanuel Caplanne , Jeff Punch
Two-phase cooling devices are used to remove and dissipate heat from high power-density electronic systems to maintain them within their operating temperature limits. The manufacture of these devices, such as heat pipes, thermosyphons or vapour chambers, involves firstly removing any internal air or non-condensable gases before charging with the required volume of working fluid. This paper presents detailed designs and operating instructions for a single bench-top station for use in a laboratory environment for the vacuum evacuation, degassing and charging of these devices. Two configurations allow for the filling of fluids which are either liquids or gases at standard temperature and pressure conditions. For liquids, the dispensed volume can be measured directly on an integrated burette, while the method of vapour transfer is used for gases.
The hardware was demonstrated by filling multiple thermosyphon devices with a number of common working fluids used in two-phase systems, including water, acetone and ammonia. It was shown to deliver precise and repeatable filling volumes with average differences compared to target volumes of 1.7% and 10.5% for liquids and gases respectively. The design is intended to be highly customisable where its size can be modified to accommodate filling volume requirements for different applications.
{"title":"A filling rig for liquid and gas working fluids for two-phase thermal management systems","authors":"Colin Butler , Emmanuel Caplanne , Jeff Punch","doi":"10.1016/j.ohx.2024.e00558","DOIUrl":"10.1016/j.ohx.2024.e00558","url":null,"abstract":"<div><p>Two-phase cooling devices are used to remove and dissipate heat from high power-density electronic systems to maintain them within their operating temperature limits. The manufacture of these devices, such as heat pipes, thermosyphons or vapour chambers, involves firstly removing any internal air or non-condensable gases before charging with the required volume of working fluid. This paper presents detailed designs and operating instructions for a single bench-top station for use in a laboratory environment for the vacuum evacuation, degassing and charging of these devices. Two configurations allow for the filling of fluids which are either liquids or gases at standard temperature and pressure conditions. For liquids, the dispensed volume can be measured directly on an integrated burette, while the method of vapour transfer is used for gases.</p><p>The hardware was demonstrated by filling multiple thermosyphon devices with a number of common working fluids used in two-phase systems, including water, acetone and ammonia. It was shown to deliver precise and repeatable filling volumes with average differences compared to target volumes of 1.7% and 10.5% for liquids and gases respectively. The design is intended to be highly customisable where its size can be modified to accommodate filling volume requirements for different applications.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00558"},"PeriodicalIF":2.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S246806722400052X/pdfft?md5=6666968a2cb2b81f7bd861dece997d67&pid=1-s2.0-S246806722400052X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141630306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-11DOI: 10.1016/j.ohx.2024.e00556
Zachary R. Sitte , Abel A. Miranda , Thomas J. DiProspero , Matthew R. Lockett
Oxygen is a vital but often overlooked variable in tissue culture experiments. Physiologically relevant oxygen tensions range from partial pressures of 100 mmHg at the alveolar-capillary interface in the lung to less than 7.6 mmHg in the hypoxic regions of solid tumors. These values are markedly lower than the partial oxygen pressure of ambient air, which is standard experimental practice. Physiologically relevant culture environments are needed to better predict cellular and tissue-level responses to drugs or potential toxins. Three commonly used methods to regulate in vitro oxygen tension involve placing cells in 1) a hypoxia chamber, 2) setups that rely on mass transport-limited microenvironments, and 3) microfabricated devices. Hypoxia chambers have the lowest barrier to entry, as they do not require laboratories to change their tissue culture setups. Here, we present a gas-regulation system for a three-zone hypoxia chamber. Each zone can maintain independent environments, with partial pressure compositions of 1–21 % O2 and 1–10 % CO2. The design incorporates small-scale fabrication techniques (e.g., laser cutting and 3D printing) and off-the-shelf electronic components for simple assembly. The hypoxia chambers are significantly lower in cost than the commercial counterparts: $1,400 for the control system or $4,100 for a complete three-zone chamber system.
{"title":"A three-zone hypoxia chamber capable of regulating unique oxygen and carbon dioxide partial pressures simultaneously","authors":"Zachary R. Sitte , Abel A. Miranda , Thomas J. DiProspero , Matthew R. Lockett","doi":"10.1016/j.ohx.2024.e00556","DOIUrl":"10.1016/j.ohx.2024.e00556","url":null,"abstract":"<div><p>Oxygen is a vital but often overlooked variable in tissue culture experiments. Physiologically relevant oxygen tensions range from partial pressures of 100 mmHg at the alveolar-capillary interface in the lung to less than 7.6 mmHg in the hypoxic regions of solid tumors. These values are markedly lower than the partial oxygen pressure of ambient air, which is standard experimental practice. Physiologically relevant culture environments are needed to better predict cellular and tissue-level responses to drugs or potential toxins. Three commonly used methods to regulate in vitro oxygen tension involve placing cells in 1) a hypoxia chamber, 2) setups that rely on mass transport-limited microenvironments, and 3) microfabricated devices. Hypoxia chambers have the lowest barrier to entry, as they do not require laboratories to change their tissue culture setups. Here, we present a gas-regulation system for a three-zone hypoxia chamber. Each zone can maintain independent environments, with partial pressure compositions of 1–21 % O<sub>2</sub> and 1–10 % CO<sub>2</sub>. The design incorporates small-scale fabrication techniques (e.g., laser cutting and 3D printing) and off-the-shelf electronic components for simple assembly. The hypoxia chambers are significantly lower in cost than the commercial counterparts: $1,400 for the control system or $4,100 for a complete three-zone chamber system<em>.</em></p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00556"},"PeriodicalIF":2.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000506/pdfft?md5=f5b09c1d42bae109e23b5c3be2c9421e&pid=1-s2.0-S2468067224000506-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-09DOI: 10.1016/j.ohx.2024.e00552
Shannon Li , Alyssa Gee , Nathan Cai , Alexandra Bermudez , Neil Y.C. Lin
The ability to simultaneously measure material mechanics and structure is central for understanding their nonlinear relationship that underlies the mechanical properties of materials, such as hysteresis, strain-stiffening and -softening, and plasticity. This experimental capability is also critical in biomechanics and mechanobiology research, as it enables direct characterizations of the intricate interplay between cellular responses and tissue mechanics. Stretching devices developed over the past few decades, however, do not often allow simultaneous measurements of the structural and mechanical responses of the sample. In this work, we introduce an open-source stretching system that can apply uniaxial strain at a submicron resolution, report the tensile force response of the sample, and be mounted on an inverted microscope for real-time imaging. Our system consists of a pair of stepper-based linear motors that stretch the sample symmetrically, a force transducer that records the sample tensile force, and an optically clear sample holder that allows for high-magnification microscopy. Using polymer samples and cellular specimens, we characterized the motion control accuracy, force measurement robustness, and microscopy compatibility of our stretching system. We envision that this uniaxial stretching system will be a valuable tool for characterizing soft and living materials.
{"title":"An open-source membrane stretcher for simultaneous mechanical and structural characterizations of soft materials and biological tissues","authors":"Shannon Li , Alyssa Gee , Nathan Cai , Alexandra Bermudez , Neil Y.C. Lin","doi":"10.1016/j.ohx.2024.e00552","DOIUrl":"10.1016/j.ohx.2024.e00552","url":null,"abstract":"<div><p>The ability to simultaneously measure material mechanics and structure is central for understanding their nonlinear relationship that underlies the mechanical properties of materials, such as hysteresis, strain-stiffening and -softening, and plasticity. This experimental capability is also critical in biomechanics and mechanobiology research, as it enables direct characterizations of the intricate interplay between cellular responses and tissue mechanics. Stretching devices developed over the past few decades, however, do not often allow simultaneous measurements of the structural and mechanical responses of the sample. In this work, we introduce an open-source stretching system that can apply uniaxial strain at a submicron resolution, report the tensile force response of the sample, and be mounted on an inverted microscope for real-time imaging. Our system consists of a pair of stepper-based linear motors that stretch the sample symmetrically, a force transducer that records the sample tensile force, and an optically clear sample holder that allows for high-magnification microscopy. Using polymer samples and cellular specimens, we characterized the motion control accuracy, force measurement robustness, and microscopy compatibility of our stretching system. We envision that this uniaxial stretching system will be a valuable tool for characterizing soft and living materials.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00552"},"PeriodicalIF":2.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000464/pdfft?md5=39e23899011f8943be69718e15983488&pid=1-s2.0-S2468067224000464-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-07DOI: 10.1016/j.ohx.2024.e00557
Camilo Acevedo-Correa , Manuel Goez , Maria C. Torres-Madronero , Tatiana Rondon
Spectral signatures allow the characterization of a surface from the reflected or emitted energy along the electromagnetic spectrum. This type of measurement has several potential applications in precision agriculture. However, capturing the spectral signatures of plants requires specialized instruments, either in the field or the laboratory. The cost of these instruments is high, so their incorporation in crop monitoring tasks is not massive, given the low investment in agricultural technology. This paper presents a low-cost clamp to capture spectral leaf signatures in the laboratory and the field. The clamp can be 3D printed using PLA (polylactic acid); it allows the connection of 2 optical fibers: one for a spectrometer and one for a light source. It is designed for ease of use and holds a leave firmly without causing damage, allowing data to be collected with less disturbance. The article compares signatures captured directly using a fiber and the proposed clamp; noise reduction across the spectrum is achieved with the clamp.
{"title":"Low-cost clamp for the measurement of vegetation spectral signatures","authors":"Camilo Acevedo-Correa , Manuel Goez , Maria C. Torres-Madronero , Tatiana Rondon","doi":"10.1016/j.ohx.2024.e00557","DOIUrl":"https://doi.org/10.1016/j.ohx.2024.e00557","url":null,"abstract":"<div><p>Spectral signatures allow the characterization of a surface from the reflected or emitted energy along the electromagnetic spectrum. This type of measurement has several potential applications in precision agriculture. However, capturing the spectral signatures of plants requires specialized instruments, either in the field or the laboratory. The cost of these instruments is high, so their incorporation in crop monitoring tasks is not massive, given the low investment in agricultural technology. This paper presents a low-cost clamp to capture spectral leaf signatures in the laboratory and the field. The clamp can be 3D printed using PLA (polylactic acid); it allows the connection of 2 optical fibers: one for a spectrometer and one for a light source. It is designed for ease of use and holds a leave firmly without causing damage, allowing data to be collected with less disturbance. The article compares signatures captured directly using a fiber and the proposed clamp; noise reduction across the spectrum is achieved with the clamp.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00557"},"PeriodicalIF":2.0,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000518/pdfft?md5=bdde53191ce36567b57b60780d139a6b&pid=1-s2.0-S2468067224000518-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141606506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To continue sleep research activities during the lockdown resulting from the COVID-19 pandemic, experiments that were previously conducted in laboratories were shifted to the homes of volunteers. Furthermore, for extensive data collection, it is necessary to use a large number of portable devices. Hence, to achieve these objectives, we developed a low-cost and open-source portable monitor (PM) device capable of acquiring electroencephalographic (EEG) signals using the popular ESP32 microcontroller. The device operates based on instrumentation amplifiers. It also has a connectivity microcontroller with Wi-Fi and Bluetooth that can be used to stream EEG signals. This portable single-channel 3-electrode EEG device allowed us to record short naps and score different sleep stages, such as wakefulness, non rapid eye movement sleep (NREM), stage 1 (S1), stage 2 (S2), stage 3 (S3) and stage 4 (S4). We validated the device by comparing the obtained signals to those generated by a research-grade counterpart. The results showed a high level of accurate similarity between both devices, demonstrating the feasibility of using this approach for extensive and low-cost data collection of EEG sleep recordings.
{"title":"A low-cost and open-hardware portable 3-electrode sleep monitoring device","authors":"Matías Rodolfo Pretel , Vanessa Vidal , Dante Kienigiel , Cecilia Forcato , Rodrigo Ramele","doi":"10.1016/j.ohx.2024.e00553","DOIUrl":"10.1016/j.ohx.2024.e00553","url":null,"abstract":"<div><p>To continue sleep research activities during the lockdown resulting from the COVID-19 pandemic, experiments that were previously conducted in laboratories were shifted to the homes of volunteers. Furthermore, for extensive data collection, it is necessary to use a large number of portable devices. Hence, to achieve these objectives, we developed a low-cost and open-source portable monitor (PM) device capable of acquiring electroencephalographic (EEG) signals using the popular ESP32 microcontroller. The device operates based on instrumentation amplifiers. It also has a connectivity microcontroller with Wi-Fi and Bluetooth that can be used to stream EEG signals. This portable single-channel 3-electrode EEG device allowed us to record short naps and score different sleep stages, such as wakefulness, non rapid eye movement sleep (NREM), stage 1 (S1), stage 2 (S2), stage 3 (S3) and stage 4 (S4). We validated the device by comparing the obtained signals to those generated by a research-grade counterpart. The results showed a high level of accurate similarity between both devices, demonstrating the feasibility of using this approach for extensive and low-cost data collection of EEG sleep recordings.</p></div>","PeriodicalId":37503,"journal":{"name":"HardwareX","volume":"19 ","pages":"Article e00553"},"PeriodicalIF":2.0,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468067224000476/pdfft?md5=46945c5c6eda62349cef32f9646d6741&pid=1-s2.0-S2468067224000476-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}