وقد تم تمويل هذا البحث من قبل NSERC، كندا.

<ol>
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ليس لدينا شيء في الكشف عنها.

ويمكن استخدام الفلورسنت الأساسية microcavities وأجهزة الاستشعار refractometric. في حين أن هناك أمثلة معزولة من microtubes &quot;طوى&quot; التي يمكن أن تكون بمثابة أجهزة استشعار ميكروفلويديك، 22 مقارنة microtubes، وسوف يكون من الأسهل الشعيرات الدموية على الاندماج في الاجهزة ميكروفلويديك ?...

يمكن الكيميائية أنظمة الاستشعار التي تتطلب كميات عينة صغيرة فقط والتي يمكن إدراجها في الأجهزة المحمولة باليد أو حقل قابلة للتشغيل-يؤدي إلى تطوير مجموعة واسعة من التكنولوجيات الجديدة. يمكن أن تشمل هذه التكنولوجيات التشخيص الميداني للأمراض والعوامل الممرضة، 1 الملوثات البيئية و 2 و سلامة الأغذية. وتمثل 3 في عدة تكنولوجيات استكشاف بنشاط عن أجهزة استشعار كيميائية ميكروفلويديك، مع الأجهزة القائمة على فيزياء الرنين مأكل السطحية (SPR) بين الأكثر تقدما. (4) هذه هي أجهزة الاستشعار الآن قادرة على اكتشاف الجزيئات الحيوية محددة كثيرة وحققت نجاحا تجاريا، على الرغم أساسا معدات المختبرات على نطاق أوسع .. 5 في السنوات الأخيرة، وارتفعت microcavities البصرية للتنافس مع SPR النظم القائمة. يمكن أن تكون حساسة بشكل مثير للدهشة Microcavities، مع إظهار القدرة على اكتشاف الفيروسات واحد 6 و ربما حتى الجزيئات الحيوية واحد <sيصل&gt; 7 (هذا الأخير لا يزال موضوع بعض الجدل، 8 ولكن ليس هناك شك في أن حدود الكشف الشامل صغيرة هي 9). في microcavities، وآلية الكشف يعتمد على التغييرات في الأصداء البصرية الناجمة عن وجود الحليلة داخل الملف المجال الكهربائي للصدى. عادة، سوف تعطى الحليلة يسبب صدى للتغيير في وتيرة المركزية، والرؤية، أو linewidth. كما هو الحال مع أنظمة SPR، يمكن microcavities بمثابة المجسات غير محددة refractometric، أو أجهزة الاستشعار functionalized لتحليل محددة. وتتميز المجهرية عازلة مع قطاع عريض دائري (مثل المجهرية، والأقراص، أو اسطوانات) من الأصداء كهرومغناطيسية تعرف باسم وسائط معرض يهمس، أو WGMs، وهو مصطلح يعود تاريخها إلى التحقيقات الرب رايليغ من الآثار الصوتية مشابهة 10 أساسا، وهو WGM البصرية عندما يحدث موجة يبحر عبر التعميم قection من الانعكاس الداخلي الكامل، والعودة إلى نقطة البداية في المرحلة. ويتضح مثال بالرنين الكهرومغناطيسي لالمكروية السيليكا في الشكل 1A. ويتميز هذا صدى من جانب واحد كحد أقصى في الاتجاه شعاعي (ن = 1)، في حين أن ما مجموعه 53 موجات تناسب جميع أنحاء خط الاستواء (ل = 53)، وتظهر فقط بعض منها. الجزء زائل من شدة الحقل يمتد إلى خارج حدود المتوسطة المجال، وبالتالي في WGM المكروية يمكن الشعور الوسط الخارجي. الشعيرات الدموية هي مثال للاهتمام خاصة من جهاز استشعار WGM مقرا لها. يمكن في WGMs، الشعرية أسطواني حول تشكيل التعميم عبر الفرع، على غرار الحال بالنسبة للكرة. إذا كان الجدار الشعرية رقيقة جدا، وهي جزء من المجال الكهرومغناطيسي يمتد إلى القناة الشعرية (1B الشكل). وهكذا، يمكن أن تكون الشعرية جهاز استشعار لميكروفلويديك analytes حقنها في القناة. هذا هو بأسيس من عمل عصابة الأساسية البصرية مرنان السائل (LCORR) 11 LCORRs تعتمد على توصيل زائل الضوء من مصدر ليزر بدقة tuneable للتحقيق في WGMs. جانبا هاما من LCORR هو أن جدران الشعيرات الدموية يجب أن تكون رقيقة (~ 1 ميكرومتر) للتأكد من أن عينات وضع وسيلة القناة. هذا يضع بعض الصعوبات في تصنيع ويسبب لها أن تكون هشة ميكانيكيا. في عملنا، وضعنا هيكل بديل نسميه microcavity الأساسية الفلورسنت (FCM). 12،13 لتشكيل FCM، ونحن معطف الجدران قناة لشعري مع fluorophore عالية الانكسار فهرس (على وجه التحديد، طبقة من أكسيد السيليكون جزءا لا يتجزأ من نقاط الكم). مطلوب من ارتفاع الرقم القياسي للفيلم لحصر الإشعاعات المنبعثة، مما يساعد على بناء حتى WGMs (الشكل 1C). وعلى النقيض من LCORR، في وسائط FCM تظهر ماكسيما حاد في الطيف مضان المنبعثة. السماكة منفيلم مهم للغاية، وإذا كان سميكا جدا في WGM لا تذوق المتوسطة في القناة الشعرية، وإذا كانت رقيقة جدا يتم فقدان الحبس البصرية وWGMs تصبح ضعيفة. وهكذا، فإن تلفيق من FCM هي عملية صعبة، تتطلب إعداد دقيق. هذا هو الموضوع الرئيسي لهذه الورقة.

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> جدول المواد </td><td> شركة </td><td> كتالوج # </td><td> تعليقات </td></tr><tr><td> السيليكا microcapillaries </td><td></td><td></td><td></td></tr><tr><td> مرنة أنابيب microbore </td><td></td><td></td><td> البولي ايثلين وtygon، الخ </td></tr><tr><td> لاصق </td><td> التميمة، نورلاند NOA </td><td></td><td></td></tr><tr><td> HSQ الذائبة في MIBK </td><td></td><td></td><td> على سبيل المثال، فوكس-15 </td></tr><tr><td> الميثانول </td><td></td><td></td><td></td></tr><tr><td> الإيثانول </td><td></td><td></td><td></td></tr><tr><td> الماء المقطر </td><td></td><td></td><td></td></tr></tbody></table> الجدول 1. قائمة المواد المستخدمة.

synthesis and operation of fluorescent-core microcavities for refractometric sensing

هذه الورقة تناقش الفلورسنت الأساسية المستندة إلى الاستشعار microcavity التي يمكن أن تعمل في إعداد تحليل ميكروفلويديك. وتستند هذه الهياكل على تشكيل طلاء الفلورسنت (QD) الكم نقطة على سطح القناة لmicrocapillary التقليدية. QDs السيليكون هي جاذبية خاصة لهذا التطبيق، ويرجع ذلك جزئيا إلى سميتها ضئيلة مقارنة II-VI وQDs مجمع II-VI، والتي يتم التحكم تشريعيا المواد في العديد من البلدان. في حين أن طيف الانبعاث الفرقة واسع وملامح، فيلم سي QD على الحائط قناة ملامح الشعرية مجموعة من القمم، وشارب ضيقة في الطيف مضان، المقابلة لالأصداء الكهرومغناطيسية للضوء محاصرين داخل الفيلم. الطول الموجي ذروة هذه الأصداء حساسة إلى متوسطة الخارجية، مما يسمح الجهاز ليعمل كجهاز استشعار refractometric التي لا تأتي أبدا QDs في اتصال جسدي مع الحليلة. التجريبيةوتناقش الأساليب المرتبطة تلفيق من microcapillaries الفلورسنت الأساسية بالتفصيل، وكذلك أساليب التحليل. وأخيرا، يتم إجراء مقارنة بين هذه الهياكل وأكثر على نطاق واسع التحقيق السائل الأساسية مرنانات حلقة البصرية، من حيث القدرات ميكروفلويديك الاستشعار عن بعد.

يمكن الانحرافات الصغيرة في الإجراء تلفيق الشعرية تؤدي إلى تغييرات كبيرة في عينة معدل النجاح. في الشكل 5 (م)، وتبين لنا أمثلة ممثل الشعيرات الدموية وكذلك فشلت واحدة ناجحة. عموما، وإشارة مرئية من عينة الناجح هو مضان أحمر جنبا إلى جنب مع كثافة عالية في جدران الش?...

Watch this Scientific Journal Video about Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing at JoVE.com

Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing

أجهزة الاستشعار microcavity الفلورسنت النواة توظيف عالية مؤشر الكم دوت الطلاء في قناة microcapillaries السيليكا. التغيرات في معامل الانكسار من السوائل ضخها في قضية قناة الشعرية تحولات في microcavity الطيف مضان التي يمكن استخدامها لتحليل المتوسطة القناة.

تجميع وتشغيل نيون الأساسية للاستشعار عن Microcavities Refractometric

This paper discusses  fluorescent core microcavity-based sensors that can operate in a microfluidic  analysis setup. These structures are based on the ...

synthesis-operation-fluorescent-core-microcavities-for-refractometric

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Engineering

12.8K Views.  University of Alberta. أجهزة الاستشعار microcavity الفلورسنت النواة توظيف عالية مؤشر الكم دوت الطلاء في قناة microcapillaries السيليكا. التغيرات في معامل الانكسار من السوائل ضخها في قضية قناة الشعرية تحولات في microcavity الطيف مضان التي يمكن استخدامها لتحليل المتوسطة القناة.

Video: Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing

Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor

Refractive index (RI) sensing is a powerful noninvasive and label-free sensing technique for the identification, detection and monitoring of microfluidic samples with a wide range of possible sensor designs such as interferometers and resonators 1,2. Most of the existing RI sensing applications focus on biological materials in aqueous solutions in visible and IR frequencies, such as DNA hybridization and genome sequencing. At terahertz frequencies, applications include quality control, monitoring of industrial processes and sensing and detection applications involving nonpolar materials.
Several potential designs for refractive index sensors in the terahertz regime exist, including photonic crystal waveguides 3, asymmetric split-ring resonators 4, and photonic band gap structures integrated into parallel-plate waveguides 5. Many of these designs are based on optical resonators such as rings or cavities. The resonant frequencies of these structures are dependent on the refractive index of the material in or around the resonator. By monitoring the shifts in resonant frequency the refractive index of a sample can be accurately measured and this in turn can be used to identify a material, monitor contamination or dilution, etc.
The sensor design we use here is based on a simple parallel-plate waveguide 6,7. A rectangular groove machined into one face acts as a resonant cavity (Figures 1 and 2). When terahertz radiation is coupled into the waveguide and propagates in the lowest-order transverse-electric (TE1) mode, the result is a single strong resonant feature with a tunable resonant frequency that is dependent on the geometry of the groove 6,8. This groove can be filled with nonpolar liquid microfluidic samples which cause a shift in the observed resonant frequency that depends on the amount of liquid in the groove and its refractive index 9.
Our technique has an advantage over other terahertz techniques in its simplicity, both in fabrication and implementation, since the procedure can be accomplished with standard laboratory equipment without the need for a clean room or any special fabrication or experimental techniques. It can also be easily expanded to multichannel operation by the incorporation of multiple grooves 10. In this video we will describe our complete experimental procedure, from the design of the sensor to the data analysis and determination of the sample refractive index.

The procedure for implementing a refractive index sensor for terahertz frequencies based on a grooved parallel-plate waveguide geometry is described here. The method yields a measurement of the refractive index of a small volume of liquid through monitoring of the shift in the resonant frequency of the waveguide structure

تيراهيرتز الاستشعار ميكروفلويديك باستخدام الاستشعار الدليل الموجي الموازي لوحة

Refractive index (RI) sensing is a powerful noninvasive and label-free sensing technique for the identification, detection and monitoring of microfluidic ...

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics

Surface acoustic waves (SAWs) can be used to drive liquids in portable microfluidic chips via the acoustic counterflow phenomenon. In this video we present the fabrication protocol for a multilayered SAW acoustic counterflow device. The device is fabricated starting from a lithium niobate (LN) substrate onto which two interdigital transducers (IDTs) and appropriate markers are patterned. A polydimethylsiloxane (PDMS) channel cast on an SU8 master mold is finally bonded on the patterned substrate. Following the fabrication procedure, we show the techniques that allow the characterization and operation of the acoustic counterflow device in order to pump fluids through the PDMS channel grid. We finally present the procedure to visualize liquid flow in the channels. The protocol is used to show on-chip fluid pumping under different flow regimes such as laminar flow and more complicated dynamics characterized by vortices and particle accumulation domains.

In this video we first describe fabrication and operation procedures of a surface acoustic wave (SAW) acoustic counterflow device. We then demonstrate an experimental setup that allows for both qualitative flow visualization and quantitative analysis of complex flows within the SAW pumping device.

تصنيع وتشغيل والتصور التدفق في سطح الموجة الصوتية يحركها الموائع الدقيقة الصوتية معاكس

Surface acoustic waves (SAWs) can be used to drive liquids in portable microfluidic chips via the acoustic counterflow phenomenon. In this video we ...

Fabrication and Operation of a Nano-Optical Conveyor Belt

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological and physical sciences over the past few decades. The progress made in this field invites further study of even smaller systems and at a larger scale, with tools that could be distributed more easily and made more widely available. Unfortunately, the fundamental laws of diffraction limit the minimum size of the focal spot of a laser beam, which makes particles smaller than a half-wavelength in diameter hard to trap and generally prevents an operator from discriminating between particles which are closer together than one half-wavelength. This precludes the optical manipulation of many closely-spaced nanoparticles and&#160;limits the&#160;resolution of optical-mechanical systems. Furthermore, manipulation using focused beams requires beam-forming or steering optics, which can be very bulky and expensive. To address these limitations in the system scalability of conventional optical trapping our lab has devised an alternative technique which utilizes near-field optics to move particles across a chip. Instead of focusing laser beams in the far-field, the optical near field of plasmonic resonators produces the necessary local optical intensity enhancement to overcome the restrictions of diffraction and manipulate particles at higher resolution. Closely-spaced resonators produce strong optical traps which can be addressed to mediate the hand-off of particles from one to the next in a conveyor-belt-like fashion. Here, we describe how to design and produce a conveyor belt using a gold surface patterned with plasmonic C-shaped resonators and how to operate it with polarized laser light to achieve super-resolution nanoparticle manipulation and transport. The nano-optical conveyor belt chip can be produced using lithography techniques and easily packaged and distributed.

The scalability and resolution of conventional optical manipulation techniques are limited by diffraction. We circumvent the diffraction limit and describe a method of optically transporting nanoparticles across a chip using a gold surface patterned with a path of closely spaced C-shaped plasmonic resonators.

تصنيع وتشغيل الحزام الناقل النانو البصرية

The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological ...

Fabrication and Operation of Acoustofluidic Devices Supporting Bulk Acoustic Standing Waves for Sheathless Focusing of Particles

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must be smaller than the incident wavelength of sound and the width of the fluidic channels are typically tens to hundreds of micrometers across, acoustofluidic devices typically use ultrasonic waves generated from a piezoelectric transducer pulsating at high frequencies (in the megahertz range). At characteristic frequencies that depend on the geometry of the device, it is possible to induce the formation of standing waves that can focus particles along desired fluidic streamlines within a bulk flow. Here, we describe a method for the fabrication of acoustophoretic devices from common materials and clean room equipment. We show representative results for the focusing of particles with positive or negative acoustic contrast factors, which move towards the pressure nodes or antinodes of the standing waves, respectively. These devices offer enormous practical utility for precisely positioning large numbers of microscopic entities (e.g., cells) in stationary or flowing fluids for applications ranging from cytometry to assembly.

Acoustofluidic devices use ultrasonic waves within microfluidic channels to manipulate, concentrate and isolate suspended micro and nanoscopic entities. This protocol describes the fabrication and operation of such a device supporting bulk acoustic standing waves to focus particles in a central streamline without the aid of sheath fluids.

تصنيع وتشغيل Acoustofluidic أجهزة دعم السائبة موجات الصوتية الدائمة للSheathless التركيز من الجسيمات

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must ...

Colloidal Synthesis of Nanopatch Antennas for Applications in Plasmonics and Nanophotonics

We present a method for colloidal synthesis of silver nanocubes and the use of these in combination with a smooth gold film, to fabricate plasmonic nanoscale patch antennas. This includes a detailed procedure for the fabrication of thin films with a well-controlled thickness over macroscopic areas using layer-by-layer deposition of polyelectrolyte polymers, namely poly(allylamine) hydrochloride (PAH) and polystyrene sulfonate (PSS). These polyelectrolyte spacer layers serve as a dielectric gap in between silver nanocubes and a gold film. By controlling the size of the nanocubes or the gap thickness, the plasmon resonance can be tuned from about 500 nm to 700 nm. Next, we demonstrate how to incorporate organic sulfo-cyanine5 carboxylic acid (Cy5) dye molecules into the dielectric polymer gap region of the nanopatch antennas. Finally, we show greatly enhanced fluorescence of the Cy5 dyes by spectrally matching the plasmon resonance with the excitation energy and the Cy5 absorption peak. The method presented here enables the fabrication of plasmonic nanopatch antennas with well-controlled dimensions utilizing colloidal synthesis and a layer-by-layer dip-coating process with the potential for low cost and large-scale production. These nanopatch antennas hold great promise for practical applications, for example in sensing, ultrafast optoelectronic devices and for high-efficiency photodetectors.

A protocol for the colloidal synthesis of silver nanocubes and fabrication of plasmonic nanoscale patch antennas with sub-10 nm gaps is presented.

الغروية توليف Nanopatch هوائيات للتطبيقات في Plasmonics وبصريات النانو

We present a method for colloidal synthesis of silver nanocubes and the use of these in combination with a smooth gold film, to fabricate plasmonic ...

Femtosecond Laser Filaments for Use in Sub-Diffraction-Limited Imaging and Remote Sensing

Probing remote matter with laser light is a ubiquitous technique used in circumstances as diverse as laser-induced breakdown spectroscopy and barcode scanners. In classical optics, the intensity that can be brought to bear on a remote target is limited by the spot size of the laser at the distance of the target. This spot size has a lower bound determined by the diffraction limit of classical optics. However, amplified femtosecond laser pulses generate intensity sufficient to modify the refractive index of the ambient air and undergo self-focusing. This self-focusing effect leads to the generation of highly intense laser filaments which maintain their intensity and small sub-millimeter diameter size at distances well beyond the classical Rayleigh length. Such intensity provides the capability of remote scanning, imaging, sensing, and spectroscopy with enhanced spatial resolution. We describe a technique for generating filaments with a femtosecond regenerative chirped-pulse amplifier, and for using the resulting filament to conduct imaging and spectroscopic measurements at remote distances of at least several meters.

High-intensity femtosecond pulses of laser light can undergo cycles of Kerr self-focusing and plasma defocusing, propagating an intense sub-millimeter-diameter beam over long distances. We describe a technique for generating and using these filaments to perform remote imaging and sensing beyond the classical diffraction limits of linear optics.

خيوط ليزر Femtosecond لاستخدامها في تصوير شبه Diffraction محدودة زمنياً، والاستشعار عن بعد

Probing remote matter with laser light is a ubiquitous technique used in circumstances as diverse as laser-induced breakdown spectroscopy and barcode ...

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing

We present a protocol for performing gas spectroscopy using infrared degenerated four-wave mixing (IR-DFWM), for the quantitative detection of gas species in the ppm-to-single-percent range. The main purpose of the method is the spatially resolved detection of low-concentration species, which have no transitions in the visible or near-IR spectral range that could be used for detection. IR-DFWM is a nonintrusive method, which is a great advantage in combustion research, as inserting a probe into a flame can change it drastically. The IR-DFWM is combined with upconversion detection. This detection scheme uses sum-frequency generation to move the IR-DFWM signal from the mid-IR to the near-IR region, to take advantage of the superior noise characteristics of silicon-based detectors. This process also rejects most of the thermal background radiation. The focus of the protocol presented here is on the proper alignment of the IR-DFWM optics and on how to align an intracavity upconversion detection system.

Here, we present a protocol to perform sensitive, spatially resolved gas spectroscopy in the mid-infrared region, using degenerate four-wave mixing combined with upconversion detection.

الأشعة تحت الحمراء من أربع موجات منحط الاختلاط مع Upconversion للكشف عن كمية الغاز الاستشعار

We present a protocol for performing gas spectroscopy using infrared degenerated four-wave mixing (IR-DFWM), for the quantitative detection of gas species ...

Synthesis, Functionalization, and Characterization of Fusogenic Porous Silicon Nanoparticles for Oligonucleotide Delivery

With the advent of gene therapy, the development of an effective in vivo nucleotide-payload delivery system has become of parallel import. Fusogenic porous silicon nanoparticles (F-pSiNPs) have recently demonstrated high in vivo gene silencing efficacy due to its high oligonucleotide loading capacity and unique cellular uptake pathway that avoids endocytosis. The synthesis of F-pSiNPs is a multi-step process that includes: (1) loading and sealing of oligonucleotide payloads in the silicon pores; (2) simultaneous coating and sizing of fusogenic lipids around the porous silicon cores; and (3) conjugation of targeting peptides and washing to remove excess oligonucleotide, silicon debris, and peptide. The particle&#8217;s size uniformity is characterized by dynamic light scattering, and its core-shell structure may be verified by transmission electron microscopy. The fusogenic uptake is validated by loading a lipophilic dye, 1,1&#39;-dioctadecyl-3,3,3&#39;,3&#39;-tetramethylindocarbocyanine perchlorate (DiI), into the fusogenic lipid bilayer and treating it to cells in vitro to observe for plasma membrane staining versus endocytic localizations. The targeting and in vivo gene silencing efficacies were previously quantified in a mouse model of Staphylococcus aureus pneumonia, in which the targeting peptide is expected to help the F-pSiNPs to home to the site of infection. Beyond its application in S. aureus infection, the F-pSiNP system may be used to deliver any oligonucleotide for gene therapy of a wide range of diseases, including viral infections, cancer, and autoimmune diseases.

We demonstrate the synthesis of fusogenic porous silicon nanoparticles for effective in vitro and in vivo oligonucleotide delivery. Porous silicon nanoparticles are loaded with siRNA to form the core, which is coated by fusogenic lipids through extrusion to form the shell. Targeting moiety functionalization and particle characterization are included.

توليف، الروغان، وتوصيف جسيمات نانوية مسامية السليكون فوسوجينيك لإيصال اليغنوكليوتيد

With the advent of gene therapy, the development of an effective in vivo nucleotide-payload delivery system has become of parallel import. Fusogenic ...

Robotic Sensing and Stimuli Provision for Guided Plant Growth

Robot systems are actively researched for manipulation of natural plants, typically restricted to agricultural automation activities such as harvest, irrigation, and mechanical weed control. Extending this research, we introduce here a novel methodology to manipulate the directional growth of plants via their natural mechanisms for signaling and hormone distribution. An effective methodology of robotic stimuli provision can open up possibilities for new experimentation with later developmental phases in plants, or for new biotechnology applications such as shaping plants for green walls. Interaction with plants presents several robotic challenges, including short-range sensing of small and variable plant organs, and the controlled actuation of plant responses that are impacted by the environment in addition to the provided stimuli. In order to steer plant growth, we develop a group of immobile robots with sensors to detect the proximity of growing tips, and with diodes to provide light stimuli that actuate phototropism. The robots are tested with the climbing common bean, Phaseolus vulgaris, in experiments having durations up to five weeks in a controlled environment. With robots sequentially emitting blue light-peak emission at wavelength 465 nm-plant growth is successfully steered through successive binary decisions along mechanical supports to reach target positions. Growth patterns are tested in a setup up to 180 cm in height, with plant stems grown up to roughly 250 cm in cumulative length over a period of approximately seven weeks. The robots coordinate themselves and operate fully autonomously. They detect approaching plant tips by infrared proximity sensors and communicate via radio to switch between blue light stimuli and dormant status, as required. Overall, the obtained results support the effectiveness of combining robot and plant experiment methodologies, for the study of potentially complex interactions between natural and engineered autonomous systems.

Distributed robot nodes provide sequences of blue light stimuli to steer the growth trajectories of climbing plants. By activating natural phototropism, the robots guide the plants through binary left-right decisions, growing them into predefined patterns that by contrast are not possible when the robots are dormant.

توفير الاستشعار الآلي والمحفزات لنمو النباتات الموجهة

Robot systems are actively researched for manipulation of natural plants, typically restricted to agricultural automation activities such as harvest, ...

Operation of the Collaborative Composite Manufacturing (CCM) System

The automated tape placement and the automated fiber placement (AFP) machines provide a safer working environment and reduce the labor intensity of workers than the traditional manual fiber placement does. Thus, the production accuracy, repeatability and efficiency of composite manufacturing are significantly improved. However, the current AFP systems can only produce the composite components with large open surface or simple revolution parts, which cannot meet the growing interest in small complex or closed structures from industry.
In this research, by employing a 1-degree of freedom (DoF) rotational stage, a 6-RSS parallel robot, and a 6-DoF serial robot, the dexterity of the AFP system can be significantly improved for manufacturing complex composite parts. The rotational stage mounted on the parallel robot is utilized to hold the mandrel and the serial robot carries the placement head to mimic two human hands that have enough dexterity to lay the fiber to the mandrel with complex contour.
Although the CCM system increases the flexibility of composite manufacturing, it is quite time-consuming or even impossible to generate the feasible off-line path, which ensures uniform lay-up of subsequent fibers considering the constraints like singularities, collisions between the fiber placement head and mandrel, smooth fiber direction change and keeping the fiber placement head along the norm of the part&#39;s surface, etc. Moreover, due to the existing positioning error of the robots, the on-line path correction is needed. Therefore, the on-line pose correction algorithm is proposed to correct the paths of both parallel and serial robots, and to keep the relative path between the two robots unchanged through the visual feedback when the constraint or singularity problems in the off-line path planning occur. The experimental results demonstrate the designed CCM system can fulfill the movement needed for manufacturing a composite structure with Y-shape.

Operation of the Collaborative Composite Manufacturing CCM System

A collaborative composite manufacturing system is developed for robotic lay-up of composite laminates using the prepreg tape. The proposed system allows the production of composite laminates with high levels of geometrical complexity. The issues in the path planning, coordination of the robots and control are addressed in the proposed method.

تشغيل نظام التصنيع المركب التعاوني (CCM)

The automated tape placement and the automated fiber placement (AFP) machines provide a safer working environment and reduce the labor intensity of ...