Ten Quick Tips for Using a Raspberry Pi

Much of biology (and, indeed, all of science) is becoming increasingly computational. We tend to think of this in regards to algorithmic approaches and software tools, as well as increased computing power. There has also been a shift towards slicker, packaged solutions--which mirrors everyday life, from smart phones to smart homes. As a result, it's all too easy to be detached from the fundamental elements that power these changes, and to see solutions as "black boxes". The major goal of this piece is to use the example of the Raspberry Pi--a small, general-purpose computer--as the central component in a highly developed ecosystem that brings together elements like external hardware, sensors and controllers, state-of-the-art programming practices, and basic electronics and physics, all in an approachable and useful way. External devices and inputs are easily connected to the Pi, and it can, in turn, control attached devices very simply. So whether you want to use it to manage laboratory equipment, sample the environment, teach bioinformatics, control your home security or make a model lunar lander, it's all built from the same basic principles. To quote Richard Feynman, "What I cannot create, I do not understand".Comment: 12 pages, 2 figure

The effect of acetone as a post-production finishing technique on entry-level material extrusion part quality

Entry-level material extrusion artefacts persistently suffer from questionable weakened end-product production quality, according to industrial standards. These limitations can be addressed by the development of improved finishing techniques that may narrow the gap between low-cost and high-end production methods in additive manufacturing. In doing so, the technology may become available to a larger spectrum of prosumers who previously were reluctant to use entry-level technology, because of these limitations. This article describes the effect that acetone has as a post-production finishing technique for low-cost artefact production. Through a serious of quantitative investigations, the study provides evidence that acetone reduces the tensile strength, increases polymer ductility and significantly reduces the surface profile roughness of thermoplastics such as acrylonitrile butadiene styrene. Potential cost and waste reduction for entry-level manufactured products are consequently identified

Programmable photonic circuits

[EN] The growing maturity of integrated photonic technology makes it possible to build increasingly large and complex photonic circuits on the surface of a chip. Today, most of these circuits are designed for a specific application, but the increase in complexity has introduced a generation of photonic circuits that can be programmed using software for a wide variety of functions through a mesh of on-chip waveguides, tunable beam couplers and optical phase shifters. Here we discuss the state of this emerging technology, including recent developments in photonic building blocks and circuit architectures, as well as electronic control and programming strategies. We cover possible applications in linear matrix operations, quantum information processing and microwave photonics, and examine how these generic chips can accelerate the development of future photonic circuits by providing a higher-level platform for prototyping novel optical functionalities without the need for custom chip fabricationBogaerts, W.; Pérez-López, D.; Capmany Francoy, J.; Miller, DAB.; Poon, J.; Englund, D.; Morichetti, F.... (2020). Programmable photonic circuits. Nature. 586(7828):207-216. https://doi.org/10.1038/s41586-020-2764-0S2072165867828Chen, X. et al. The emergence of silicon photonics as a flexible technology platform. Proc. IEEE 106, 2101–2116 (2018).Smit, M., Williams, K. & van der Tol, J. Past, present, and future of InP-based photonic integration. APL Photonics 4, 050901 (2019).Capmany, J. & Perez, D. Programmable Integrated Photonics (Oxford Univ. Press, 2020). The first book on the subject of programmable photonics gives a detailed overview of the fundamental principles, architectures and potential applications.Marpaung, D., Yao, J. & Capmany, J. Integrated microwave photonics. Nat. Photon. 13, 80–90 (2019).Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K. & Lowery, A. J. Programmable photonic signal processor chip for radiofrequency applications. Optica 2, 854–859 (2015).Shen, Y. et al. Deep learning with coherent nanophotonic circuits. Nat. Photon. 11, 441–446 (2017).Harris, N. C. et al. Linear programmable nanophotonic processors. Optica 5, 1623–1631 (2018). One of the largest-scale demonstrations of a programmable photonic circuit, using a silicon photonics forward-only mesh that maps 26 input modes onto 26 output modes, for use in deep learning and quantum information processing.Miller, D. A. B. Self-configuring universal linear optical component. Photon. Res. 1, 1–15 (2013). This foundational paper in the field of programmable photonics is the first to bring together waveguide meshes with self-configuration algorithms that require no active computation, including the concept of the self-aligning beam coupler.Carolan, J. et al. Universal linear optics. Science 349, 711–716 (2015).Harris, N. C. et al. Large-scale quantum photonic circuits in silicon. Nanophotonics 5, 456–468 (2016).Notaros, J. et al. Programmable dispersion on a photonic integrated circuit for classical and quantum applications. Opt. Express 25, 21275–21285 (2017).Clements, W. R., Humphreys, P. C., Metcalf, B. J., Kolthammer, W. S. & Walmsley, I. A. An optimal design for universal multiport interferometers. Optica 12, 1460–1465 (2016).Perez-Lopez, D. Programmable integrated silicon photonics waveguide meshes: optimized designs and control algorithms. IEEE J. Sel. Top. Quantum Electron. 26, 8301312 (2020).Ribeiro, A., Ruocco, A., Vanacker, L. & Bogaerts, W. 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A comprehensive overview of the various ways in which a programmable photonic circuit can be used to process microwave signals, and on how this type of circuit is transitioning from custom ASPICs to generic programmable PICs.Hall, T. J. & Hasan, M. Universal discrete Fourier optics RF photonic integrated circuit architecture. Opt. Express 24, 7600–7610 (2016).Dyakonov, I. V. et al. Reconfigurable photonics on a glass chip. Phys. Rev. Appl. 10, 044048 (2018).Shokraneh, F., Geoffroy-Gagnon, S., Nezami, M. S. & Liboiron-Ladouceur, O. A single layer neural network implemented by a 4×4 MZI-based optical processor. IEEE Photonics J. 11, 4501612 (2019).Lu, L., Zhou, L. & Chen, J. Programmable SCOW mesh silicon photonic processor for linear unitary operator. Micromachines 10, 646 (2019).Qiang, X. et al. Large-scale silicon quantum photonics implementing arbitrary two-qubit processing. Nat. Photon. 12, 534–539 (2018).Wang, J. et al. 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Light. Technol. 38, 723–735 (2020).Miller, D. A. B. Analyzing and generating multimode optical fields using self-configuring networks. Optica 7, 794–801 (2020).Morizur, J.-F. et al. Programmable unitary spatial mode manipulation. J. Opt. Soc. Am. A 27, 2524 (2010).Labroille, G. et al. Efficient and mode selective spatial mode multiplexer based on multi-plane light conversion. Opt. Express 22, 15599–15607 (2014).Tanomura, R., Tang, R., Ghosh, S., Tanemura, T. & Nakano, T. Robust integrated optical unitary converter using multiport directional couplers. J. Light. Technol. 38, 60–66 (2020).Miller, D. A. B. Setting up meshes of interferometers – reversed local light interference method. Opt. Express 25, 29233 (2017).Li, H. W. et al. Calibration and high fidelity measurement of a quantum photonic chip. New J. Phys. 15, 063017 (2013).Cong, G. et al. Arbitrary reconfiguration of universal silicon photonic circuits by bacteria foraging algorithm to achieve reconfigurable photonic digital-to-analog conversion. Opt. Express 27, 24914 (2019).Pérez, D. et al. Multipurpose silicon photonics signal processor core. Nat. Commun. 8, 1–9 (2017). The first experimental demonstration of a recirculating waveguide mesh with seven unit cells that can be programmed to perform more than a hundred different functions.Pérez, D., Gasulla, I. & Capmany, J. Field-programmable photonic arrays. Opt. Express 26, 27265 (2018).Rahim, A., Spuesens, T., Baets, R. & Bogaerts, W. Open-access silicon photonics: current status and emerging initiatives. Proc. IEEE 106, 2313–2330 (2018).Munoz, P. et al. Foundry developments toward silicon nitride photonics from visible to the mid-infrared. IEEE J. Sel. Top. Quantum Electron. 25, 8200513 (2019).Teng, M. et al. Miniaturized silicon photonics devices for integrated optical signal processors. J. Light. Technol. 38, 6–17 (2020).Sacher, W. D. et al. Monolithically integrated multilayer silicon nitride-on-silicon waveguide platforms for 3-D photonic circuits and devices. Proc. IEEE 106, 2232–2245 (2018).Baudot, C. et al. Developments in 300mm silicon photonics using traditional CMOS fabrication methods and materials. In 2017 IEEE Int. Electron Devices Meeting, 765–768 (IEEE, 2017).Fahrenkopf, N. M. et al. The AIM photonics MPW: a highly accessible cutting edge technology for rapid prototyping of photonic integrated circuits. IEEE J. Sel. Top. Quantum Electron. 25, 8201406 (2019).Chiles, J. et al. Multi-planar amorphous silicon photonics with compact interplanar couplers, cross talk mitigation, and low crossing loss. APL Photonics 2, 116101 (2017).Van Campenhout, J., Green, W. M. J., Assefa, S. & Vlasov, Y. A. Integrated NiSi waveguide heaters for CMOS-compatible silicon thermo-optic devices. Opt. Lett. 35, 1013–1015 (2010).Masood, A. et al. Comparison of heater architectures for thermal control of silicon photonic circuits. In Proc. 10th Int. Conference on Group IV Photonics 83–84 (IEEE, 2013).Milanizadeh, M., Aguiar, D., Melloni, A. & Morichetti, F. Canceling thermal cross-talk effects in photonic integrated circuits. J. Light. Technol. 37, 1325–1332 (2019).Soref, R. A. & Bennett, B. R. Electrooptical effects in silicon. IEEE J. Quantum Electron. 23, 123–129 (1987).Reed, G. T., Mashanovich, G., Gardes, F. Y. & Thomson, D. J. Silicon optical modulators. Nat. Photon. 4, 518–526 (2010); corrigendum 4, 660 (2010).Memon, F. A. et al. Silicon oxycarbide platform for integrated photonics. J. Light. Technol. 38, 784–791 (2020).Jin, W., Polcawich, R. G., Morton, P. A. & Bowers, J. E. Piezoelectrically tuned silicon nitride ring resonator. Opt. Express 26, 3174–3187 (2018).Hosseini, N. et al. Stress-optic modulator in TriPleX platform using a piezoelectric lead zirconate titanate (PZT) thin film. Opt. Express 23, 14018 (2015).De Cort, W., Beeckman, J., Claes, T., Neyts, K. & Baets, R. Wide tuning of silicon-on-insulator ring resonators with a liquid crystal cladding. Opt. Lett. 36, 3876–3878 (2011).Xing, Y. et al. Digitally controlled phase shifter using an SOI slot waveguide with liquid crystal infiltration. IEEE Photonics Technol. Lett. 27, 1269–1272 (2015).Abel, S. et al. Large Pockels effect in micro- and nanostructured barium titanate integrated on silicon. Nat. Mater. 18, 42–47 (2019).Desiatov, B., Shams-Ansari, A., Zhang, M., Wang, C. & Lončar, M. Ultra-low-loss integrated visible photonics using thin-film lithium niobate. Optica 6, 380 (2019).Alexander, K. et al. Nanophotonic Pockels modulators on a silicon nitride platform. Nat. Commun. 9, 3444 (2018).Leuthold, J. et al. Silicon-organic hybrid electro-optical devices. IEEE J. Sel. Top. Quantum Electron. 19, 114–126 (2013).Errando-Herranz, C. et al. MEMS for photonic integrated circuits. IEEE J. Sel. Top. Quantum Electron. 26, 8200916 (2020).Quack, N. et al. MEMS-enabled silicon photonic integrated devices and circuits. IEEE J. Quantum Electron. 56, 8400210 (2020).Hoessbacher, C. et al. The plasmonic memristor: a latching optical switch. Optica 1, 198 (2014).Ríos, C. et al. Integrated all-photonic non-volatile multi-level memory. Nat. Photon. 9, 725–732 (2015).Wuttig, M., Bhaskaran, H. & Taubner, T. Phase-change materials for non-volatile photonic applications. Nat. Photon. 11, 465–476 (2017).Morichetti, F. et al. Non-invasive on-chip light observation by contactless waveguide conductivity monitoring. IEEE J. Sel. Top. Quantum Electron. 20, 292–301 (2014).Jayatilleka, H., Shoman, H., Chrostowski, L. & Shekhar, S. Photoconductive heaters enable control of large-scale silicon photonic ring resonator circuits. Optica 6, 84–91 (2019).Grillanda, S. et al. Non-invasive monitoring and control in silicon photonics using CMOS integrated electronics. Optica 1, 129 (2014).Annoni, A. et al. Automated routing and control of silicon photonic switch fabrics. IEEE J. Sel. Top. Quantum Electron. 22, 169–176 (2016).Dumais, P. et al. Silicon photonic switch subsystem with 900 monolithically integrated calibration photodiodes and 64-fiber package. J. Light. Technol. 36, 233–238 (2018).Chen, H., Luo, X. & Poon, A. W. Cavity-enhanced photocurrent generation by 1.55 μm wavelengths linear absorption in a p–i–n diode embedded silicon microring resonator. Appl. Phys. Lett. 95, 171111 (2009).Ribeiro, A. & Bogaerts, W. Digitally controlled multiplexed silicon photonics phase shifter using heaters with integrated diodes. Opt. Express 25, 29778 (2017).Zimmermann, L. et al. BiCMOS silicon photonics platform. In Optical Fiber Communication Conference Th4E-5 (Optical Society of America, 2015).Orcutt, J. S. et al. Nanophotonic integration in state-of-the-art CMOS foundries. Opt. Express 19, 2335–2346 (2011).Stojanović, V. et al. Monolithic silicon-photonic platforms in state-of-the-art CMOS SOI processes. Opt. Express 26, 13106 (2018).Carroll, L. et al. Photonic packaging: transforming silicon photonic integrated circuits into photonic devices. Appl. Sci. 6, 426 (2016).Patterson, D., De Sousa, I. & Archard, L.-M. The future of packaging with silicon photonics. Chip Scale Rev. 21, 1–10 (2017).Ribeiro, A., Declercq, S., Khan, U., Wang, M. & Van Iseghem, L. Column-row addressing of thermo-optic phase shifters for controlling large silicon photonic circuits. IEEE J. Sel. Top. Quantum Electron. 26, 6100708 (2020).Pantouvaki, M. et al. Active components for 50 Gb/s NRZ-OOK optical interconnects in a silicon photonics platform. J. Light. Technol. 35, 631–638 (2017).Chen, H. et al. 100-Gbps RZ data reception in 67-GHz Si-contacted germanium waveguide p-i-n photodetectors. J. Light. Technol. 35, 722–726 (2017).Pérez, D., Gasulla, I. & Capmany, J. Toward programmable microwave photonics processors. J. Light. 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MECHANICAL TESTING OF FUSED FILAMENT 3-D PRINTED COMPONENTS FOR DISTRIBUTED MANUFACTURING

Fused filament fabrication (FFF)-based open-source 3-D printers offer the potential of decentralized manufacturing both in developing and developed countries. Unfortunately, a severe lack of data and standards relating to material properties and printed components limit this potential. This thesis first investigates the mechanical properties of a wide-range of FFF materials and provides a database of mechanical strength of the materials tested. The results demonstrate that the tensile strength of a 3-D printed specimen depends largely on the mass of the specimen, which provides a means to estimate the strength of 3-D printed components. Then this information is used to evaluate a bicycled pedal, which was 3-D printed and tested following the CEN (European Committee for Standardization) standards for racing bicycles. The results show the pedals meet the CEN standards and can be used on bicycles at lower costs than standard pedals. This investigation indicates the viability of distributed manufacturing

Distributed manufacturing of flexible products: Technical feasibility and economic viability

Distributed manufacturing even at the household level is now well established with the combined use of open source designs and self-replicating rapid prototyper (RepRap) 3-D printers. Previous work has shown substantial economic consumer benefits for producing their own polymer products. Now flexible filaments are available at roughly 3-times the cost of more conventional 3-D printing materials. To provide some insight into the potential for flexible filament to be both technically feasible and economically viable for distributed digital manufacturing at the consumer level this study investigates 20 common flexible household products. The 3-D printed products were quantified by print time, electrical energy use and filament consumption by mass to determine the cost to fabricate with a commercial RepRap 3-D printer. Printed parts were inspected and when necessary tested for their targeted application to ensure technical feasibility. Then, the experimentally measured cost to DIY manufacturers was compared to low and high market prices for comparable commercially available products. In addition, the mark-up and potential for long-term price declines was estimated for flexible filaments by converting thermoplastic elastomer (TPE) pellets into filament and reground TPE from a local recycling center into filament using an open source recyclebot. This study found that commercial flexible filament is economically as well as technically feasible for providing a means of distributed home-scale manufacturing of flexible products. The results found a 75% savings when compared to the least expensive commercially equivalent products and 92% when compared to high market priced products. Roughly, 160 flexible objects must be substituted to recover the capital costs to print flexible materials. However, as previous work has shown the Lulzbot Mini 3-D printer used in this study would provide more than a 100% ROI printing one object a week from hard thermoplastics, the upgrade needed to provide flexible filament capabilities can be accomplished with 37 average substitution flexible prints. This, again easily provides a triple digit return on investment printing one product a week. Although these savings, which are created by printing objects at home are substantial, the results also have shown the savings could be further increased to 93% when the use of a pellet extruder and TPE pellets, and 99% if recycled TPE filament made with a recyclebot is used. The capital costs of a recyclebot can be recovered in the manufacturing of about 9 kg of TPE filament, which can be accomplished in less than a week, enabling improved environmental impact as well as a strong financial return for heavy 3-D printer users

Distributed Manufacturing of Flexible Products: Technical Feasibility and Economic Viability

International audienceDistributed manufacturing even at the household level is now well established with the combined use of open source designs and self-replicating rapid prototyper (RepRap) 3-D printers. Previous work has shown substantial economic consumer benefits for producing their own polymer products. Now flexible filaments are available at roughly 3-times the cost of more conventional 3-D printing materials. To provide some insight into the potential for flexible filament to be both technically feasible and economically viable for distributed digital manufacturing at the consumer level this study investigates 20 common flexible household products. The 3-D printed products were quantified by print time, electrical energy use and filament consumption by mass to determine the cost to fabricate with a commercial RepRap 3-D printer. Printed parts were inspected and when necessary tested for their targeted application to ensure technical feasibility. Then, the experimentally measured cost to DIY manufacturers was compared to low and high market prices for comparable commercially available products. In addition, the markup and potential for long-term price declines was estimated for flexible filaments by converting thermoplastic elastomer (TPE) pellets into filament and reground TPE from a local recycling center into filament using an open source recyclebot. This study found that commercial flexible filament is economically as well as technically feasible for providing a means of distributed home-scale manufacturing of flexible products. The results found a 75% savings when compared to the least expensive commercially equivalent products and 92% when compared to high market priced products. Roughly, 160 flexible objects must be substituted to recover the capital costs to print flexible materials. However, as previous work has shown the Lulzbot Mini 3-D printer used in this study would provide more than a 100% ROI printing one object a week from hard thermoplastics, the upgrade needed to provide flexible filament capabilities can be accomplished with 37 average substitution flexible prints. This, again easily provides a triple digit return on investment printing one product a week. Although these savings, which are created by printing objects at home are substantial, the results also have shown the savings could be further increased to 93% when the use of a pellet extruder and TPE pellets, and 99% if recycled TPE filament made with a recyclebot is used. The capital costs of a recyclebot can be recovered in the manufacturing of about 9 kg of TPE filament, which can be accomplished in less than a week, enabling improved environmental impact as well as a strong financial return for heavy 3-D printer users

Madala maksumusega elektromüograafide rakendatavus ergonoomikalises hindamises

A thesis for applying for the degree of Doctor of Philosophy in Engineering Sciences.Every year a considerable amount of gross domestic product in several countries is lost due to work-related musculoskeletal disorders (WMSDs). Thus, one of the goals of ergonomics is to prevent WMSDs. A body of knowledge required to prevent WMSDs has existed for decades; however, the exploitation of this knowledge is hindered by the shortcomings in the risk assessment methods. As a rule, objective methods should be preferred to subjective methods, though often access to objective methods is restricted by the cost of the apparatus. The potential to make one of such devices more accessible by reducing the costs was investigated in the thesis. The thesis focused on the electromyograph – a device to study and monitor the electrical activity produced by skeletal muscles. Nowadays one can assemble an electromyograph from low-cost semi-universal components; however, the functionality and usability of such a device is unknown. At first the technical characteristics of components that can be used to assemble an electromyograph were evaluated. Then the electromyographs were assembled and tested in the laboratory and in the field. The results showed that the low-cost electromyographs may be partially utilised in ergonomic risk assessment; however, the use of such equipment in comparison to commercial high-cost apparatus increases the demands on user knowledge, skills and time expenditure. On the other hand, the functionality of the do-it-yourself electromyograph may exceed the commercial device.Tööga seotud luu- ja lihaskonna ülekoormushaiguste tõttu kaotavad riigid igal aastal märkimisväärse osa sisemajanduse kogutoodangust. Seetõttu on üheks ergonoomika eesmärgiks luu- ja lihaskonna ülekoormushaiguste ennetamine. Teadmised töötaja ülekoormuse ennetamiseks on olemas juba aastakümneid. Paraku takistavad teadmiste tõhusat rakendamist puudused riskihindamise meetodites. Riskide hindamisel tuleb subjektiivsetele meetoditele eelistada objektiivseid meetodeid, kuid sageli piirab objektiivsete meetodite kasutamist mõõteseadmete maksumus. Doktoritöös uuriti ühe sellist liiki mõõteseadme, lihaste elektrilise aktiivsuse uurimiseks mõeldud seireseadme ehk elektrimüograafi kättesaadavuse ja rakendamise suurendamise võimalust seadme maksumuse vähendamisega. Nüüdisajal on võimalus elektromüograafe kokku panna madala maksumusega ja pool-universaalsetest komponentidest. Samas pole selge, milline on sellisel viisil valmistatud elektromüograafi funktsionaalsus ja kasutatavus. Doktoritöös hinnati esmalt elektromüograafi madala maksumusega komponentide tehnilisi omadusi ning seejärel katsetati koostatud elektromüograafe laboris ja töökeskkonnas. Doktoritöö andis kinnitust, et madala maksumusega elektromüograafe on võimalik riskihindamisel osaliselt rakendada, kuid selliste seadmete kasutamine eeldab riskihindajalt põhjalikumaid teadmisi ja oskusi ning suuremat ajakulu kui kallite kommertsseadmete kasutamine. Samas võib spetsialisti kokkupandud elektromüograafi funktsionaalsus kommertsseadmeid ületada.Publication of this thesis is supported by the Estonian University of Life Sciences. This research was supported by European Regional Development Fund’s Doctoral Studies and Internationalisation Programme DoR

Design and performance evaluation of advanced QoS-enabled service-oriented architectures for the Internet of Things

The Internet of Things (IoT) is rapidly becoming reality, the cut off prices as well as the advancement in the consumer electronic field are the two main training factor. For this reason, new application scenarios are designed every days and then new challenges that must be addressed. In the future we will be surrounded by many smart devices, which will sense and act on the physical environment. Such number of smart devices will be the building block for a plethora of new smart applications which will provide to end user new enhanced service. In this context, the Quality of Service (QoS) has been recognized as a non functional key requirement for the success of the IoT. In fact, in the future IoT, we will have different applications each one with different QoS requirements, which will need to interact with a finite set of smart device each one with its QoS capabilities. Such mapping between requested and offered QoS must be managed in order to satisfy the end users. The work of this thesis focus on how to provide QoS for IoT in a cross-layer manner. In other words, our main goal is to provide QoS support that, on one hand, helps the back-end architecture to manage a wide set of IoT applications, each one with its QoS requirements, while, on the other hand, enhances the access network by adding QoS capabilities on top of smart devices. We analyzed existing QoS framework and, based on the status of the art, we derive a novel model specifically tailored for IoT systems. Then we define the procedures needed to negotiate the desired QoS level and to enforce the negotiated QoS. In particular we take care of the Thing selection problem which is raised whenever more than one thing can be exploited to obtain a certain service. Finally we considered the access network by providing different solutions to handle QoS with different grain scale. We proposed a totally transparent solution which exploits virtualization and proxying techniques to differentiate between different class of client and provide a class based prioritization schema. Then we went further by designing a QoS framework directly on top of a standard IoT protocol called Constrained Application Protocol (CoAP). We designed the QoS support to enhance the Observing paradigm which is of paramount importance especially if we consider industrial applications which might benefit from a certain level of QoS assurances

Catching trains of thought; UX guidelines for facilitating knowledge exchange between makers

This thesis establishes directions for the design of the user experience of a service that could facilitate knowledge exchange practices amongst makers. To achieve this the thesis sets out to answer the question “How to design the user experience of a multi-platform application to enable it to facilitate knowledge exchange between makers?”. A process consisting of a research for design and a research through design stage is utilized to generate a suitable answer. The research for design stage includes a literature review and field research. The literature review investigates the motivations for developing as a maker, the physical spaces in which makers are active, communities of practice, and knowledge creation in collaborative processes. The key findings from this review are validated and furthered upon through field research. The field research explores activity in and on maker communities in Helsinki through interviews and collaborative design sessions with local makers. The findings from the research for design stage are then condensed into twelve design directions. The research through design stage describes the design, evaluation and testing of two interactive prototypes of a multi-platform application. The first prototype is used as a presentation aid during evaluations on two events, a large Maker Faire and the Spring Demo Day in Aalto University Media Lab. Based on the evaluations the prototype is iterated and then subjected to usability tests in a Fab Lab. The results of the research through design stage reveal three themes regarding the user experience of a system aimed to facilitate knowledge exchange. To answer the main question the design directions and the themes are combined. The findings urge designers of systems aiming to facilitate knowledge exchange between makers to pay attention to three guidelines. These guidelines are: stories of creativity, the overlap of intuition and education, and the need for structure and support. The findings of this project provide insights necessary to reduce the loss of knowledge in maker communities, and in this way develop their efficacy. Improving the ability of these communities is argued to have a positive influence on existing industrial processes. The author collaborates with Taro Morimoto during the project described in this thesis. Taro Morimoto utilized this project to research the digital ecosystem of makers and the technical aspects of the multi-platform application as part of his thesis for the Master of Arts in New Media