385 research outputs found
soft robotic manipulation of onions and artichokes in the food industry
This paper presents the development of a robotic solution for a problem of fast manipulation and handling of onions or artichokes in the food industry. The complete solution consists of a parallel robotic manipulatior, a specially designed end-effector based on a customized vacuum suction cup, and a computer vision software developed for pick and place operations. First, the selection and design process of the proposed robotic solution to fit with the initial requeriments is presented, including the customized vacuum suction cup. Then, the kinematic analysis of the parallel manipulator needed to develop the robot control system is reviewed. Moreover, computer vision application is presented inthe paper. Hardware details of the implementation of the building prototype are also shown. Finally, conclusions and future work show the current status of the project
Sound absorption of textile material using a microfibres resistive layer
[EN] Acoustic comfort is a basic human need. One of the adverse effects of noise is its interference with speech discrimination. Textile materials are suitable to be used as sound absorptive materials and thus help to improve acoustic comfort in rooms. Micro-fibre fabrics can be considered as better sound absorbers than regular fibre fabrics mainly due to the higher surface of its fibres and bigger contact area with the air thus, allowing greater dissipation of sound energy. In this work, the use of a microfibre woven fabric as an upstream layer is analysed considering acoustic issues. Authors demonstrate it improves the sound absorption of a polyester nonwoven, resulting in a material suitable for absorption at the sound frequencies of the human voice.Segura-Alcaraz, MDP.; Bonet-Aracil, M.; Segura Alcaraz, JG.; Montava Segui, I. (2017). Sound absorption of textile material using a microfibres resistive layer. IOP Conference Series Materials Science and Engineering. 254:1-6. doi:10.1088/1757-899X/254/7/072022S1625
Explanatory Supplement of the ISOGAL-DENIS Point Source Catalogue
We present version 1.0 of the ISOGAL-DENIS Point Source Catalogue (PSC),
containing more than 100,000 point sources detected at 7 and/or 15 micron in
the ISOGAL survey of the inner Galaxy with the ISOCAM instrument on board the
Infrared Space Observatory (ISO). These sources are cross-identified, wherever
possible, with near-infrared (0.8-2.2 micron) data from the DENIS survey. The
overall surface covered by the ISOGAL survey is about 16 square degrees, mostly
(95%) distributed near the Galactic plane (|b| < 1 deg), where the source
extraction can become confusion limited and perturbed by the high background
emission. Therefore, special care has been taken aimed at limiting the
photometric error to ~0.2 magnitude down to a sensitivity limit of typically 10
mJy. The present paper gives a complete description of the entries and the
information which can be found in this catalogue, as well as a detailed
discussion of the data processing and the quality checks which have been
completed. The catalogue is available via the VizieR Service at the Centre de
Donn\'ees Astronomiques de Strasbourg (CDS,
http://vizier.u-strasbg.fr/viz-bin/VizieR/) and also via the server at the
Institut d'Astrophysique de Paris (http://www-isogal.iap.fr/). A more complete
version of this paper, including a detailed description of the data processing,
is available in electronic form through the ADS service.Comment: 21 pages, 7 figures. A&A in press. Full length version with 32
figures and detailed description of the data processing is available here:
http://www-isogal.iap.fr/Publications/ExplSupplFull.ps.g
Surface Modification of Polypropilene Non-woven Substrates by Padding with Antistatic Agents for Deposition of Polyvinyl Alcohol (PVA) Nanofiber Webs by Electrospinning
In recent years, the electrospinning process has become one of the most interesting processes to obtain nanofiber webs with interesting properties for uses in a wide variety of industrial sectors such as filtration, chemical barriers, medical devices, etc., as a consequence of the relatively high surface-to-volume ratio. Among the wide variety of polymers, polyvinyl alcohol (PVA) offers good advantages since it is water-soluble and this fact enables easy processing by electrospinning. There are many variables and parameters to be considered in order to optimize PVA nanofiber webs: some of them are related to the polymer solution, some others are related to the process, and some of them are related to the collector substrate. In this work a study on the effects of two different surface pre-treatments on a nonwoven polypropylene substrate as a collector of PVA nanofiber webs has been carried out. In particular, a chemical treatment with anionic antistatics and a physical treatment with lowpressure plasma have been investigated. The effects of these pre-treatments on morphology of
PVA nanofiber webs have been evaluated by scanning electron microscopy. Results show that surface resistivity is one of the main parameters influencing the web formation as well as the nature of the electric charge achieved by the pre-treatment. The plasma treatment promotes changes in surface resistivity but it is not enough for good web deposition. Chemical pre-treatment (padding) with anionic antistatic leads to a decrease in surface resistivity up to values in the 1 Ă— 109– 1 Ă— 1011 Ω which is enough for good nanofiber deposition.This work was supported by the Ministerio de Ciencia y Tecnologia, grant number DPI2007-66849-C02-02.Blanes, M.; Marco, B.; Gisbert, MJ.; Bonet Aracil, MA.; Balart Gimeno, RA. (2010). Surface Modification of Polypropilene Non-woven Substrates by Padding with Antistatic Agents for Deposition of Polyvinyl Alcohol (PVA) Nanofiber Webs by Electrospinning. Textile Research Journal. 80(13):1335-1346. https://doi.org/10.1177/0040517509358801S133513468013Burger, C., Hsiao, B. S., & Chu, B. (2006). NANOFIBROUS MATERIALS AND THEIR APPLICATIONS. Annual Review of Materials Research, 36(1), 333-368. doi:10.1146/annurev.matsci.36.011205.123537Dersch, R., Steinhart, M., Boudriot, U., Greiner, A., & Wendorff, J. H. (2005). Nanoprocessing of polymers: applications in medicine, sensors, catalysis, photonics. Polymers for Advanced Technologies, 16(2-3), 276-282. doi:10.1002/pat.568Frenot, A., & Chronakis, I. S. (2003). Polymer nanofibers assembled by electrospinning. Current Opinion in Colloid & Interface Science, 8(1), 64-75. doi:10.1016/s1359-0294(03)00004-9GOPAL, R., KAUR, S., MA, Z., CHAN, C., RAMAKRISHNA, S., & MATSUURA, T. (2006). Electrospun nanofibrous filtration membrane. Journal of Membrane Science, 281(1-2), 581-586. doi:10.1016/j.memsci.2006.04.026Qin, X.-H., & Wang, S.-Y. (2006). Filtration properties of electrospinning nanofibers. Journal of Applied Polymer Science, 102(2), 1285-1290. doi:10.1002/app.24361Ren, G., Xu, X., Liu, Q., Cheng, J., Yuan, X., Wu, L., & Wan, Y. (2006). Electrospun poly(vinyl alcohol)/glucose oxidase biocomposite membranes for biosensor applications. Reactive and Functional Polymers, 66(12), 1559-1564. doi:10.1016/j.reactfunctpolym.2006.05.005Lee, S., & Obendorf, S. K. (2007). Use of Electrospun Nanofiber Web for Protective Textile Materials as Barriers to Liquid Penetration. Textile Research Journal, 77(9), 696-702. doi:10.1177/0040517507080284Heikkilä, P., Sipilä, A., Peltola, M., Harlin, A., & Taipale, A. (2007). Electrospun PA-66 Coating on Textile Surfaces. Textile Research Journal, 77(11), 864-870. doi:10.1177/0040517507078241Boudriot, U., Dersch, R., Greiner, A., & Wendorff, J. H. (2006). Electrospinning Approaches Toward Scaffold Engineering?A Brief Overview. Artificial Organs, 30(10), 785-792. doi:10.1111/j.1525-1594.2006.00301.xButtafoco, L., Kolkman, N. G., Engbers-Buijtenhuijs, P., Poot, A. A., Dijkstra, P. J., Vermes, I., & Feijen, J. (2006). Electrospinning of collagen and elastin for tissue engineering applications. Biomaterials, 27(5), 724-734. doi:10.1016/j.biomaterials.2005.06.024Lee, L. J. (2006). Polymer Nanoengineering for Biomedical Applications. Annals of Biomedical Engineering, 34(1), 75-88. doi:10.1007/s10439-005-9011-6Chew, S. Y., Hufnagel, T. C., Lim, C. T., & Leong, K. W. (2006). Mechanical properties of single electrospun drug-encapsulated nanofibres. Nanotechnology, 17(15), 3880-3891. doi:10.1088/0957-4484/17/15/045Huang, Z.-M., He, C.-L., Yang, A., Zhang, Y., Han, X.-J., Yin, J., & Wu, Q. (2006). Encapsulating drugs in biodegradable ultrafine fibers through co-axial electrospinning. Journal of Biomedical Materials Research Part A, 77A(1), 169-179. doi:10.1002/jbm.a.30564Kim, H.-W., Lee, H.-H., & Knowles, J. C. (2006). Electrospinning biomedical nanocomposite fibers of hydroxyapatite/poly(lactic acid) for bone regeneration. Journal of Biomedical Materials Research Part A, 79A(3), 643-649. doi:10.1002/jbm.a.30866Taepaiboon, P., Rungsardthong, U., & Supaphol, P. (2006). Drug-loaded electrospun mats of poly(vinyl alcohol) fibres and their release characteristics of four model drugs. Nanotechnology, 17(9), 2317-2329. doi:10.1088/0957-4484/17/9/041Ding, B., Kim, H.-Y., Lee, S.-C., Shao, C.-L., Lee, D.-R., Park, S.-J., … Choi, K.-J. (2002). Preparation and characterization of a nanoscale poly(vinyl alcohol) fiber aggregate produced by an electrospinning method. Journal of Polymer Science Part B: Polymer Physics, 40(13), 1261-1268. doi:10.1002/polb.10191Cui, W., Li, X., Zhou, S., & Weng, J. (2006). Investigation on process parameters of electrospinning system through orthogonal experimental design. Journal of Applied Polymer Science, 103(5), 3105-3112. doi:10.1002/app.25464Deitzel, J. ., Kleinmeyer, J., Harris, D., & Beck Tan, N. . (2001). The effect of processing variables on the morphology of electrospun nanofibers and textiles. Polymer, 42(1), 261-272. doi:10.1016/s0032-3861(00)00250-0Lyons, J., Li, C., & Ko, F. (2004). Melt-electrospinning part I: processing parameters and geometric properties. Polymer, 45(22), 7597-7603. doi:10.1016/j.polymer.2004.08.071Theron, S. A., Zussman, E., & Yarin, A. L. (2004). Experimental investigation of the governing parameters in the electrospinning of polymer solutions. Polymer, 45(6), 2017-2030. doi:10.1016/j.polymer.2004.01.024Kilic, A., Oruc, F., & Demir, A. (2008). Effects of Polarity on Electrospinning Process. Textile Research Journal, 78(6), 532-539. doi:10.1177/0040517507081296Reneker, D. H., & Chun, I. (1996). Nanometre diameter fibres of polymer, produced by electrospinning. Nanotechnology, 7(3), 216-223. doi:10.1088/0957-4484/7/3/009Lee, J. S., Choi, K. H., Ghim, H. D., Kim, S. S., Chun, D. H., Kim, H. Y., & Lyoo, W. S. (2004). Role of molecular weight of atactic poly(vinyl alcohol) (PVA) in the structure and properties of PVA nanofabric prepared by electrospinning. Journal of Applied Polymer Science, 93(4), 1638-1646. doi:10.1002/app.20602Mit-uppatham, C., Nithitanakul, M., & Supaphol, P. (2004). Effects of Solution Concentration, Emitting Electrode Polarity, Solvent Type, and Salt Addition on Electrospun Polyamide-6 Fibers: A Preliminary Report. Macromolecular Symposia, 216(1), 293-300. doi:10.1002/masy.200451227Kim, S. J., Lee, C. K., & Kim, S. I. (2005). Effect of ionic salts on the processing of poly(2-acrylamido-2-methyl-1-propane sulfonic acid) nanofibers. Journal of Applied Polymer Science, 96(4), 1388-1393. doi:10.1002/app.21567ZHANG, C., YUAN, X., WU, L., & SHENG, J. (2006). PROPERTIES OF ULTRAFINE FIBROUS POLY(VINYL ALCOHOL) MEMBRANES BY ELECTROSPINNING. Acta Polymerica Sinica, 006(2), 294-297. doi:10.3724/sp.j.1105.2006.00294Supaphol, P., & Chuangchote, S. (2008). On the electrospinning of poly(vinyl alcohol) nanofiber mats: A revisit. Journal of Applied Polymer Science, 108(2), 969-978. doi:10.1002/app.27664Jones, R. N. (1962). THE EFFECTS OF CHAIN LENGTH ON THE INFRARED SPECTRA OF FATTY ACIDS AND METHYL ESTERS. Canadian Journal of Chemistry, 40(2), 321-333. doi:10.1139/v62-050Yao, L., Haas, T. W., Guiseppi-Elie, A., Bowlin, G. L., Simpson, D. G., & Wnek, G. E. (2003). Electrospinning and Stabilization of Fully Hydrolyzed Poly(Vinyl Alcohol) Fibers. Chemistry of Materials, 15(9), 1860-1864. doi:10.1021/cm0210795Wei, Q. F., Gao, W. D., Hou, D. Y., & Wang, X. Q. (2005). Surface modification of polymer nanofibres by plasma treatment. Applied Surface Science, 245(1-4), 16-20. doi:10.1016/j.apsusc.2004.10.013Garcia, D., Sanchez, L., Fenollar, O., Lopez, R., & Balart, R. (2008). Modification of polypropylene surface by CH4–O2 low-pressure plasma to improve wettability. Journal of Materials Science, 43(10), 3466-3473. doi:10.1007/s10853-007-2322-2LĂłpez, R., Sanchis, R., GarcĂa, D., Fenollar, O., & Balart, R. (2009). Surface characterization of hydrophilic coating obtained by low-pressure CH4O2plasma treatment on a polypropylene film. Journal of Applied Polymer Science, 111(6), 2992-2997. doi:10.1002/app.29324Tsai, P. P., Schreuder-Gibson, H., & Gibson, P. (2002). Different electrostatic methods for making electret filters. Journal of Electrostatics, 54(3-4), 333-341. doi:10.1016/s0304-3886(01)00160-
Auto-adaptative Robot-aided Therapy based in 3D Virtual Tasks controlled by a Supervised and Dynamic Neuro-Fuzzy System
This paper presents an application formed by a classification method based on the architecture of ART neural network (Adaptive Resonance Theory) and the Fuzzy Set Theory to classify physiological reactions in order to automatically and dynamically adapt a robot-assisted rehabilitation therapy to the patient needs, using a three-dimensional task in a virtual reality system. Firstly, the mathematical and structural model of the neuro-fuzzy classification method is described together with the signal and training data acquisition. Then, the virtual designed task with physics behavior and its development procedure are explained. Finally, the general architecture of the experimentation for the auto-adaptive therapy is presented using the classification method with the virtual reality exercise
Studies for the application of an adaptative controller to hydroturbine generators
This paper describes some studies made towards the automatization of hydroturbine generators with microcomputers. The overall design will include an automata controlling the starting-up and shutting-down procedure as well as an self-tuning regulator for the speed control. A self-tuning regulator based on the classical pole-assignment-method is studied. The algorithm uses a fast procedure for solving the polynomial equation implicit to selfturner regulator. This procedure is very simple from a computational point of view as only applications of elementary transformations on a 2 x 2 polynomial matrix are needed.The algorithm has been programmed on a Digital PDP 1103 computer and applied to some test problems
Influence of glyoxal in the physical characterization of PVA nanofibres
[EN] The influence of solution composition is directly related to the properties of polyvinyl alcohol (PVA) nanofibers. Electrospinning is a viable technique to develop PVA nanofibers. The presence of a crosslinking agent such as glyoxal can produce variations not only in anti-water solubility effect, but also in the morphology of the electrodeposited fibers. The objective of this study was to characterize the influence of glyoxal on PVA nanofibers. Thus, we studied fiber dimensions, the weight of deposited fibers, and fiber crystallinity. The relation between those properties and the properties of the nanofiber web (color, opacity, and roughness) were studied. In this study we changed glyoxal concentration. Scanning electron microscopy, differential scanning calorimetry, and atomic force microscopy showed changes in the fiber properties. We could observe how the diameter fiber increased, the collector surface was widely covered, and the fiber crystallinity decreased. Regarding the properties of the web, the roughness decreased and the color turned whiter.The authors wish to acknowledge the financial support of the MINISTERIO DE CIENCIA E INNOVACION. Ref: CIT-020000-2008-016 for financial support. Also, the microscopy services at UPV are gratefully acknowledged for their assistance in using AFM techniques, and Octavio Fenollar at UPV is gratefully acknowledged for his assistance in using calorimetric techniques.Blanes, M.; Gisbert, MJ.; Marco, B.; Bonet Aracil, MA.; Gisbert Paya, J.; Balart Gimeno, RA. (2010). Influence of glyoxal in the physical characterization of PVA nanofibres. Textile Research Journal. 80(14):1465-1472. doi:10.1177/0040517509357654S14651472801
Fast pyrolysis of halogenated plastics recovered from waste computers
The disposal of waste computers is an issue that is gaining increasing interest around the world. In this paper, results from the fast pyrolysis in a fluidized bed reactor of three different waste computer monitor casings composed of mainly acrylonitrile-butadiene-styrene (ABS) copolymer and two different waste computer body casings composed of mostly poly(vinyl chloride) (PVC) type polymers are presented. Preliminary characterization of the waste plastics was investigated using coupled thermogravimetric analysis-Fourier transform infrared spectrometry (TGA-FT-IR). The results showed that the plastics decomposed in two stages. For the ABS-containing monitor casings, aromatic and aliphatic material were released in the first and second stages. The PVC-containing computer body casing samples showed a first-stage evolution of HCl and a second stage evolution of aromatic and aliphatic material and further HCl. In addition, each of the five plastics was fast-pyrolyzed in a laboratory-scale fluidized bed reactor at 500 °C. The fluidized bed pyrolysis led to the conversion of most of the plastics to pyrolysis oil, although the two PVC computer body cases produced large quantities of HCl. The pyrolysis oils were characterized by GC-MS and it was found that they were chemically very heterogeneous and contained a wide range of aliphatic, aromatic, halogenated, oxygenated, and nitrogenated compounds
Robotized spraying of prefabricated panels
A robotic manufacturing cell of pre-fabricated glass reinforced cement panels for construction industry has been developed by DISAM for the Spanish construction company Dragados, SA. The main contribution of the developed system is the automatic programming and control of the whole plan. The architect's 3D-drawing of the building facade done on a CAD system serves as input. From the CAD design, the optimum facade to panels partition is obtained. In order to manufacture each panel, automatic task and path planning are performed for the equipment present in the manufacturing cell: spraying robot, PLCs, control computer, etcThis work was supported by the construction company Dragados, S.A. and the Spanish Ministry of Industry under project PAUTA 1691/91. The authors thank A. Garcia, E. Pinto, 1. Florez,
E. Marquez, C. Corpas, 1. Arauzo and A. Cases, and the staff of the Caracola factory in Torrejon de Ardoz (Madrid).
Thanks are also due to Christian Schafer for his assistance with the final manuscript.Publicad
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