uu.seUppsala universitets publikasjoner
Endre søk
Begrens søket
1 - 33 of 33
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Berglund, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Lotfi, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Dynamic characterization and modelling of a dual-axis beam steering device for performance understanding, optimization, and control design2013Inngår i: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 23, nr 4, s. 045020-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a lumped thermal model of a dual-axis laser micromirror device for beam steering in a free-space optical (FSO) communication system, designed for fractionated spacecraft. An FSO communication system provides several advantages, such as larger bandwidth, smaller size and weight of the communication payload and less power consumption. A dual-axis mirror device is designed and realized using microelectromechanical systems technology. The fabrication is based on a double-sided, bulk micromachining process, where the mirror actuates thermally by joints consisting of v-grooves filled with the SU-8 polymer. The size of the device, consisting of a mirror, which is deflectable versus its frame in one direction, and through deflection of the frame in the other, is 15.4 × 10.4 × 0.3 mm3. In order to further characterize and understand the micromirror device, a Simulink state-space model of the actuator is set up using thermal and mechanical properties from a realized actuator. A deviation of less than 2% between the modelled and measured devices was obtained in an actuating temperature range of 20–200 °C. The model of the physical device was examined by evaluating its performance in vacuum, and by changing physical parameters, such as thickness and material composition. By this, design parameters were evaluated for performance gain and usability. For example, the crosstalk between the two actuators deflecting the mirror along its two axes in atmospheric pressure is projected to go down from 97% to 6% when changing the frame material from silicon to silicon dioxide. A feedback control system was also designed around the model in order to examine the possibility to make a robust control system for the physical device. In conclusion, the model of the actuator presented in this paper can be used for further understanding and development of the actuator system.

  • 2.
    Berglund, Martin
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Persson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Microfluidics integrable plasma source powered by a silicon through-substrate split-ring resonator2013Inngår i: Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS EUROSENSORS XXVII), 2013, s. 2608-2611Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    A novel microplasma source, based on a microstrip split-ring resonator design with electrodes integrated in its silicon substrate, was designed, manufactured and evaluated. This device should offer straightforward integration with other MEMS components, and has a plasma discharge gap with a controlled volume and geometry, with potential for microfluidics. Two realized devices were resonant at around 2.9 GHz with quality factors of 26.6 and 18.7. Two different plasma ignition modes were observed, where the plasma at low pressures was not confined to the gap but rather appeared between the ends of the electrodes on the backside.

  • 3.
    Bruhn, F
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. Fysiska sektionen, Institutionen för fysik och materialvetenskap, Materialvetenskap. ÅSTC.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. Fysiska sektionen, Institutionen för fysik och materialvetenskap, Materialvetenskap. ÅSTC.
    Warell, J
    Institutionen för astronomi och rymdfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. Fysiska sektionen, Institutionen för fysik och materialvetenskap, Materialvetenskap.
    Lagerkvist, C - I
    Institutionen för astronomi och rymdfysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. Fysiska sektionen, Institutionen för fysik och materialvetenskap, Materialvetenskap.
    Kaznov, V
    Jones, J A
    Stenmark, L
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. Fysiska sektionen, Institutionen för fysik och materialvetenskap, Materialvetenskap. ÅSTC.
    A Spherical Inflatable Micro Rover System for Mars Exploration2005Inngår i: 56th IAC in, 2005Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 4.
    Bruhn, Fredrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Warell, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Lagerkvist, Claes-Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för astronomi och rymdfysik.
    Kaznov, Viktor
    Jones, Jack A
    Stenmark, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    A Preliminary Design for a Spherical Inflatable Microrover for Planetary Exploration2008Inngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 63, nr 5-6, s. 618-631Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Spherical Mobile Investigator for Planetary Surface (SMIPS) concept aims at making use of the latest developments within extreme miniaturization of space systems. The introduction of Microelectromechanical Systems (MEMSs) and higher level Multifunctional Microsystems (MMSs) design solutions gives the robot high performance per weight unit. The untraditional spherical shape makes it easily maneuverable and thus provides a platform for scientific investigations of interplanetary bodies. Preliminary investigations of the SMIPS concept show several advantages over conventional robots and rovers in maneuverability, coverage, size, and mass. A locomotion proof-of-concept has been Studied together with a new distributed on-board data system configuration. This paper discusses theoretical robot analysis, an overall concept, possible science, enabling technologies, and how to perform scientific investigations. A preliminary design of an inflatable multifunctional shell is proposed.

  • 5.
    Böhnke, Tobias
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära och åskforskning.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Hultåker, Annette
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Köhler, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära och åskforskning.
    Edoff, Marika
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik.
    Roos, Arne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Ribbing, Carl-Gustaf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Surfaces with high solar reflectance and high thermal emittance on structured silicon for spacecraft thermal control2008Inngår i: Optical materials (Amsterdam), ISSN 0925-3467, E-ISSN 1873-1252, Vol. 30, nr 9, s. 1410-1421Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Presented here is an examination of unstructured and structured (by anisotropic etching), monocrystalline silicon wafers coated with sputter deposited aluminum and chemical vapor deposited silicon dioxide for high solar reflectance and high thermal emittance, respectively. The topography of the samples was characterized with optical and scanning electron microscopy. Optical properties were examined with reflectance and transmittance spectroscopy, partly by usage of an integrating sphere. The measurement results were used to estimate the equilibrium temperature of the surfaces in space. The suitability of the surfaces with high solar reflectance and high thermal emittance to aid in the thermal control of miniaturized, highly integrated components for space applications is discussed. A silicon dioxide layer on a metal layer results in a slightly lower reflectance when compared to surfaces with only a metal layer, but might be beneficial for miniaturized space components and modules that have to dissipate internally generated heat into open space. Additionally, it is an advantage to microstructure the emitting surface for enhanced radiation of excess heat.

  • 6.
    Cheng, Shi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrovågs- och terahertzteknik.
    Yousef, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    79 GHz Slot Antennas Based on Substrate Integrated Waveguides (SIW) in a Flexible Printed Circuit Board2009Inngår i: IEEE Transactions on Antennas and Propagation, ISSN 0018-926X, E-ISSN 1558-2221, Vol. 57, nr 1, s. 64-71Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The design, fabrication and characterization of 79 GHz slot antennas based on substrate integrated waveguides (SIW) are presented in this paper. All the prototypes are fabricated in a polyimide flex foil using printed circuit board (PCB) fabrication processes. A novel concept is used to minimize the leakage losses of the SlWs at millimeter wave frequencies. Different losses in the SlWs are analyzed. SIW-based single slot antenna, longitudinal and four-by-four slot array antennas are numerically and experimentally studied. Measurements of the   antennas show approximately 4.7%, 5.4% and 10.7% impedance bandwidth (S-11 = -10 dB) with 2.8 dBi, 6.0 dBi and 11.0 dBi maximum antenna gain around 79 GHz, respectively. The measured results are in good agreement with the numerical simulations.

  • 7. Janhunen, P.
    et al.
    Toivanen, P. K.
    Polkko, J.
    Merikallio, S.
    Salminen, P.
    Haeggstrom, E.
    Seppänen, H.
    Kurppa, R.
    Ukkonen, J.
    Kiprich, S.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Richter, L.
    Krömer, O.
    Rosta, R.
    Noorma, M.
    Envall, J.
    Lätt, S.
    Mengali, G.
    Quarta, A. A.
    Koivisto, H.
    Tarvainen, O.
    Kalvas, T.
    Kauppinen, J.
    Nuottajärvi, A.
    Obraztsov, A.
    Invited Article: Electric solar wind sail: Toward test missions2010Inngår i: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 81, nr 11, s. 111301-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.

  • 8. Janhunen, P.
    et al.
    Toivanen, P.K.
    Polkko, J.
    Merikallio, S.
    Salminen, P.
    Haeggström, E.
    Seppänen, H.
    Kurppa, R.
    Ukkonen, J.
    Kiprich, S.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Richter, L.
    Krömer, O.
    Roste, R.
    Noorma, M.
    Envall, J.
    Lätt, S.
    Mengali, G.
    Quarta, A.
    Koivisto, H.
    Tarvainen, O.
    Kalvas, T.
    Kauppinen, J.
    Nuottajärvi, A.
    Obraztsov, A.
    Electric solar wind sail in.scpace propulsion status report2010Inngår i: Proceedings of Space Propulsion, 2010, San Sebastian, Spain, May 3-6, 2010, 2010Konferansepaper (Fagfellevurdert)
  • 9.
    Janhunen, Pekka
    et al.
    Finnish Meteorological Institute.
    Merikallio, Sini
    Finnish Meteorological Institute.
    Toivanen, Petri
    Finnish Meteorological Institute.
    Polkko, Jouni
    Finnish Meteorological Institute.
    Haeggström, Edward
    University of Helsinki, Department of Physics.
    Seppänen, Henri
    University of Helsinki, Department of Physics.
    Kurppa, Ristp
    University of Helsinki, Department of Physics.
    Ukkonen, Jukka
    University of Helsinki, Department of Physics.
    Ylitalo, Tuomo
    University of Helsinki, Department of Physics.
    Kiprich, Sergiy
    National Science Center Kharkov Institute of Physics and Technology.
    Koivisto, Hannu
    University of Jyväskylä, Accelerator Laboratory.
    Kalvas, Taneli
    University of Jyväskylä, Accelerator Laboratory.
    Tarvainen, Olli
    University of Jyväskylä, Accelerator Laboratory.
    Kauppinen, Janne
    University of Jyväskylä, Accelerator Laboratory.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Grönland, Tor-Arne
    Johansson, Håkan
    Rangsten, Pelle
    Vinterhav, Emil
    Noorma, Mart
    University of Tartu.
    Envall, Jouni
    University of Tartu.
    Lätt, Silver
    University of Tartu.
    Allik, Viljo
    University of Tartu.
    Voormansik, Kaupo
    University of Tartu.
    Kvell, Urmas
    Lebreton, Jean-Pierre
    Hallikainen, Martti
    Aalto University.
    Praks, Jaan
    Aalto University.
    Krömer, Olaf
    Rosta, Roland
    Salminen, Pekka
    Mengali, Giovanni
    University of Pisa.
    Quarta, Alessandro
    University of Pisa.
    Aliasi, Generoso
    University of Pisa.
    Marcuccio, Salvo
    Pergola, Pierpaolo
    Giusti, Nicola
    Electric Solar Wind Sail in tailwind2011Inngår i: EPSC-DPS Joint Meeting 2011, 2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Electric Solar Wind Sail (E-sail) is a novelpropulsion concept that enables faster space travel tomany solar system targets. E-sail uses charged solarwind particles as the source of its propulsion. This isachieved by deploying long, conducting and chargedtethers, which get pushed by the solar wind byCoulomb drag [1].E-sail technology is being developed to technicalreadiness level (TRL) 4-5 by the European Union’sSeventh Framework Programme for Research andTechnological Development, EU FP7, in a projectnamed ESAIL (http://www.electric-sailing.fi/fp7).Prototypes of the key parts are to be produced. Thedesign will be scalable so that a real solar winddemonstration mission could be scaled up from them.We review here the latest results of the constantlyevolving E-sail project.

  • 10.
    Janhunen, Pekka
    et al.
    Finnish Meteorological Institute.
    Toivanen, Petri
    Finnish Meteorological Institute.
    Merikallio, Sini
    Finnish Meteorological Institute.
    Polkko, Jouni
    Finnish Meteorological Institute.
    Haeggström, Edward
    University of Helsinki, Department of Physics.
    Seppänen, Henri
    University of Helsinki, Department of Physics.
    Kurppa, Risto
    University of Helsinki, Department of Physics.
    Ukkonen, Jukka
    University of Helsinki, Department of Physics.
    Ylitalo, Tuomo
    University of Helsinki, Department of Physics.
    Kiprich, Sergiy
    National Science Center Kharkov Institute of Physics and Technology.
    Koivisto, Hannu
    University of Jyväskylä, Accelerator Laboratory.
    Kalvas, Taneli
    University of Jyväskylä, Accelerator Laboratory.
    Tarvainen, Olli
    University of Jyväskylä, Accelerator Laboratory.
    Kauppinen, Janne
    University of Jyväskylä, Accelerator Laboratory.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Grönland, Tor-Arne
    Johansson, Håkan
    Rangsten, Pelle
    Vinterhav, Emil
    Noorma, Mart
    University of Tartu.
    Envall, Jouni
    University of Tartu.
    Lätt, Silver
    University of Tartu.
    Allik, Viljo
    University of Tartu.
    Voormansik, Kaupo
    University of Tartu.
    Kvell, Urmas
    Lebreton, Jean-Pierre
    Hallikainen, Martti
    Aalto University.
    Praks, Jaan
    Aalto University.
    Krömer, Olaf
    Rosta, Roland
    Salminen, Pekka
    Mengali, Giovanni
    University of Pisa.
    Quarta, Alessandro
    University of Pisa.
    Aliasi, Generoso
    University of Pisa.
    Marcuccio, Salvo
    Pergola, Pierpaolo
    Giusti, Nicola
    Electric Solar Wind Sail Propulsion System Development2011Inngår i: International Electric Propulsion Conference, 2011Konferansepaper (Fagfellevurdert)
  • 11.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A compact projection system enabling topographical measurements for a miniaturized submersible explorer2011Inngår i: Proceedings of the 16th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS), 2011, IEEE conference proceedings, 2011, s. 2518-2521Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To enable photogrammetry of underwater images using a miniaturized submersible explorer, a compact projection system has been developed. By registering the deformation of a known projected pattern, using a laser and a diffractive optical element (DOE), the distance to, shape and size of an object can be calculated. The DOE has been designed, using in-house developed software, and manufactured using microstructure technology. Distances to objects 45 to 30 cm away were determined to within 0.5 cm, and the developed GUI was able to recreate the shape from the measurements for easier examination of the object.

  • 12.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A compact system to extract topography information from scenes viewed by a miniaturized submersible explorer2012Inngår i: Sensors and Actuators A-Physical, ISSN 0924-4247, E-ISSN 1873-3069, Vol. 188, nr SI, s. 401-410Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In images taken underwater, it is generally difficult to correctly extract distances and geometric informationof objects. Different techniques, collectively referred to as photogrammetry, exist to measurefeatures in images. One of these is to project a reference pattern onto an object in a scene viewed by acamera, and register the distortion of this pattern, to calculate the shape of, and distance to, that object.This method is implemented here on a miniaturized submersible explorer equipped with, among manyother instruments, a camera. Diffractive optical elements (DOEs) have been designed and manufacturedusing microsystems technology, to, together with a laser diode, camera, and in-house developed software,provide a compact system for projecting reference patterns and analyzing their deformations. Thesystem has been characterized by measuring the distances and angles of objects in a water tank, andattempting to reproduce their shapes. The range of operation of the system, verified to be at least onemeter, is limited by the compact mounting in the small submersible and the cameras’ performance.The system was found to work well under turbid conditions as well as in water containing larger particles.Together with a vehicle-mounted camera, the compact and low-power DOE laser projection systemenables topographical measurement.

  • 13.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Almqvist, Monica
    Electrical Measurements, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Simulation and Evaluation of Small High-Frequency Side Scan Sonars Using COMSOL2009Inngår i: COMSOL Conference 2009 Milan, 2009Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    High frequency side-scan sonar, to be fitted on a miniaturized submersible explorer, have been simulated and built. The purpose of this study is to see if COMSOL Multiphysics can be used to predict the performance of the sonar, especially the beam width, setting the resolution of the system. Four models were created, from simple 2-D geometries to more complex 3-D models. The simulated beam widths were compared with measurements to see which of the models agreed best. It was found that all models agree with the experimental results to varying degrees, and mostly with a difference of less than 6%. . It was found that the simplest model agreed best with the measurements, closely followed by the most complex model. Also taking the computational load into consideration the simpler model might then be a better choice to use.

  • 14.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Almqvist, Monica
    Electrical Measurements, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Simulation, manufacturing, and evaluation of a sonar for a miniaturized submersible explorer2010Inngår i: IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, ISSN 0885-3010, E-ISSN 1525-8955, Vol. 57, nr 2, s. 490-495Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Single-beam side-scan sonar elements, to be fitted on a miniaturized submersible, are here simulated, manufactured, and evaluated. Finite element analysis simulations are compared with measurements, and an overall observation is that the agreement between simulations and measurements deviates from the measured values of 1.5 to 2°, for the narrow lobe angle, by less than 10% for most models. An overall finding is that the lobe width along the track direction can be accurately simulated and, hence, the resolution of the sonars can be predicted. This paper presents, to the authors’ knowledge, the world’s smallest side-scan sonars.

  • 15.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Lekholm, Ville
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Monica, Almqvist
    Dept of Measurement Technology and Industrial Electrical Engineering, Lund University.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Enclosure-Induced Interference Effects in a Miniaturized Sidescan Sonar2012Inngår i: IEEE Journal of Oceanic Engineering, ISSN 0364-9059, E-ISSN 1558-1691, Vol. 37, nr 2, s. 236-243Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    On, for instance, the miniaturized submersible explorer, Deeper Access, Deeper Understanding (DADU), only 20 cm in length and 5 cm in diameter, the sidescan sonar needs to be tightly mounted in the hull. Finite element analysis (FEA) as well as physical measurements were used to investigate the effects of beam interaction with acoustically nearby rigid boundaries. Computer simulations showed the first major dip in the beam shape to vary in strength, size, and position with the enclosure wall height, from a position of 47° at 0.0-mm wall height to 32° at 3.0-mm wall height. Hydrophonic measurements on the manufactured test device confirmed these values to within 9%, varying between 47° and 29°. In addition, Schlieren imaging was proposed and used as a noninvasive means of qualitative beam shape characterization. A field test was performed with the enclosure height set to 0 and 3 mm. With the latter height, a dark band, corresponding to a sonar sensitivity dip at about 30° in the beam, appeared in the sonar image. It was found that the beam shape is sensitive to small mounting errors, in this case where the wavelength of the sonar is on the same size scale as the enclosure. Furthermore, it was found that FEA models can be used to accurately predict enclosure effects on sonar beam shapes, and Schlieren imaging can be used to visually detect the shape deformations in mounted sonar devices.

  • 16.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wagner, Sven
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Miniaturized submersible for exploration of aqueous environments on Earth and beyond2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Some of the most likely environments to support extraterrestrial life in our solar system are the ice-covered moons, suchas Europa, thought to harbor a liquid ocean underneath its frozen crust. Exploration, however, necessitates an ice-penetratingcryobot, or a long and narrow borehole, and the subsequent deployment of a small submersible, a hydrobot, with severe sizerestrictions imposed on its scientific payload. As a stepping stone for exploration of such environments, a small instrumentladenedsubmersible vehicle is currently under development.Employment of a large set of instruments capable of characterizing the aqueous environment, imaging the surroundingsand collecting microorganisms is essential for the determination of habitability. Despite the submersible being only 20 cm inlength and 5 cm in diameter, a high degree of functionality is facilitated here through the use of miniaturization technologies. Forinstance, a compact laser-illuminated diffractive optical element, paired with a high-resolution camera, enable photogrammetryand the reconstruction of objects’ shapes in 3-D space. Also for imaging, the world’s smallest side-scanning sonar has beendeveloped to acoustically image, either where water is too turbid for the camera, or where longer range is necessary. Currently,the sonar exhibits centimeter resolution and ranges over 30 meters. On the sensor side, a most vital oceanographic instrument, theCTD, used to measure the conductivity, temperature, and depth of water, has been heavily miniaturized and preliminaryevaluated. Additionally, a water sampler combining integrated selection and enriching capabilities to filter out and accommodate,e.g., microbes in the size range of 1-10 μm, is under development. Among other parts, its high-pressure valves and microfluidicacoustic traps have already been realized.For remote operation and upload of measurement data or images, or even live streaming of video, the submersible will betethered with a bi-directionally transmitting fiber optic cable, also capable of charging the onboard batteries for long missions.The one kilometer long fiber will be fitted within the hull, and by reeling out the fiber from the submersible, drag will be reduced.Herein, test results and images of the vehicle and its complete, and continuously developed, subsystems are presented.The vehicle, and its subsystems as stand-alone instruments, will enable the exploration of previously unreachable analogenvironments on Earth, vital to the field of astrobiology, and act as a forerunner to a submersible hydrobot that can explore icecoveredoceans elsewhere in our solar system.

  • 17.
    Jonsson, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Ogden, Sam
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Smedfors, Katarina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Wagner, Sven
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Miniaturized submersible for exploration of small aqueous environments2011Inngår i: Oceans’11 MTS/IEEE Kona, Hilton Waikoloa Village, Kona, Hawai‘i September 19-22, 2011, 2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Remotely operated vehicles (ROVs) are commonlyused for sub-surface exploration. However, multi-functionalROVs tend to be fairly large, while preferred small and compactROVs suffer from limited functionality. The Deeper Access,Deeper Understanding (DADU) project aims to develop a smallsubmersible concept using miniaturization technologies to enablea high functionality. An operator is able to maneuver the vehiclewith five degrees of freedom using eight small thrusters, while aset of accelerometers and gyros monitor the orientation of thesubmersible. A single fiber optic cable will connect thesubmersible to a control station and enable simultaneous dataand command transfers. Rechargeable battery packs providepower to the submersibles subsystems during operation. Thesewill be rechargeable through the fiber connection. A forwardlooking camera is aided by a laser topography measurementsystem, where distances, sizes and shapes of objects in view canbe determined to within 0.5 cm. For murkier environments, orwhen a more extensive mapping of the surroundings is needed,the small high-frequency side-scanning sonar can be used.Salinity calculations of the water will be available throughmeasurements of the conductivity, temperature and depth.Samples of water and particles within it will be enabled through awater sampler with an enriching capability. Flow sensors will beable to measure the water movement around the submersible’shull. The submersible and its subsystems are under continuousdevelopment. The vehicle itself, and its subsystems as stand-aloneinstruments, will enable the exploration of previouslyunreachable submerged environments, such as the sub-glaciallakes found in Iceland and Antarctica, or other submerged smallenvironments, such as pipe and cave systems.

  • 18.
    Kratz, Henrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Eriksson, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Karlsson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Köhler, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Analysis of Thermal Transients in an Asymmetric Silicon-Based Heat Dissipation Stage2007Inngår i: IEEE transactions on components and packaging technologies (Print), ISSN 1521-3331, E-ISSN 1557-9972, Vol. 30, nr 3, s. 444-456Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal management is crucial for many microsystems and electronics applications (and that of miniaturized spacecraft is particularly demanding). This paper presents thermal modeling and scaling of a generic multiwafer silicon segment for placement in between two devices, or as a stage for a single one, in need of asymmetric thermal management. The unit is autonomous, i.e., it doesn't require any input signals or power. It comprises paraffin acting both as a heat sink, or thermal storage, and a material activating heat switches. The former mitigates heat bursts and accommodates power initially generated in, e.g., attached electronics, whereas the latter facilitates heat dissipation through heat guides during more intensive operation. Its function and physical properties are described in detail. A lumped thermal model has been constructed and implemented in the Simulink environment to investigate effects from: physical scaling of the unit, and change of its boundary temperature and coupling thereto, power generated, its emission and absorption properties and area fractions dedicated for passive devices, infrared (IR) emission, and heat guides on the unit's exterior, as well as fractional cross sections of paraffin, heat guides and other structural material in its interior. Conclusions, based on simulation results, are made and design rules based on the thermal modeling are presented. It was found that a 68 times 68 mm module could handle more than 10 W for 6 min in its heat sink mode alone. Subjected to 15 W for the same time, the module enters its active dissipation mode by closing its heat switches. A lateral increase and simultaneous vertical decrease of the unit's size resulted in overheating, whereas most scaling did not cause depletion of the heat sink. Changing the area fractions of various constituents also indicated operational stability with exception for excessive enlargement of passive heat guide material, exchanging structural material with paraffin, - or severely limiting IR emission (by emitter area reduction or using low emission material), or using high absorbance material. Altering the boundary temperature and interface conductance proved to be means of biasing the system to various operating temperatures.

  • 19.
    Kratz, Henrik
    et al.
    ÅSTC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Materialvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik.
    Karlsson, Mikael
    Materialvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Materialvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik.
    Stenmark, Lars
    ÅSTC. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Materialvetenskap. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik.
    A Transceiver with Integrated Thermal Control for Spacecraft2002Inngår i: MEMSWAVE Heraklion 26th-28th June 2002, 2002Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 20.
    Kratz, Henrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. ÅSTC.
    Öjefors, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik.
    Stenmark, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektronik. ÅSTC.
    Vital parts for RF microsystems under development for nanospacecraft at the Ångström Space Technology Centre (ÅSTC)2004Inngår i: Proceedings of MEMSWAVE, 2004.: The Ångström Laboratory, Uppsala, Sweden, 30 June-2 July, 2004, 2004Konferansepaper (Annet vitenskapelig)
  • 21. Köhler, Johan
    et al.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Modular Multifunctional Silicon Microsystems for Spacecraft Applications2007Konferansepaper (Fagfellevurdert)
  • 22.
    Lotfi, Sara
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Palmer, Kristoffer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Hybrid microtransmitter for free-space optical spacecraft communication: design, manufacturing, and characterization2009Inngår i: Proc. SPIEPhotonics West, MOEMS and Miniaturized Systems VIII, Jan 24-29, San Jose, CA, 2009, s. 72080N-12-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Opticalintra-communication links are investigated by several currently operational qualification missions.Compared with RF communication systems, the optical domain obtains awider bandwidth, enables miniaturized spacecraft and reduced power consumption. Inthis project, a microtransmitter is designed and manufactured for formationflying spacecraft with transmission rates of 1 Gbit/s. Simulations inMatlab and Simulink show that a BER of 10-9 canbe achieved with aperture sizes of 1 cm and atransmitter output peak power of 12 mW for a distanceof 10 km. The results show that the performance ofthe communication link decreases due to mechanical vibrations in thespacecraft together with a narrow laser beam. A dual-axis microactuatordesigned as a deflectable mirror has been developed for thelaser beam steering where the fabrication is based on adouble-sided, bulk micromachining process. The mirror actuates by joints consistingof v-grooves filled with SU-8 polymer. The deflection is controlledby integrated resistive heaters in the joints causing the polymerto expand thermally. Results show that the mirror actuates 20-30°in the temperature interval 25-250°C. Flat Fresnel lenses made ofPyrex 7740 are used to collimate the laser beam. Theselenses are simulated in the Comsol software and optimized fora 670 nm red VCSEL. The lenses are manufactured usinglithography and reactive ion etching. All tests are made ina normal laboratory environment, but the effect of the spaceenvironment is discussed

  • 23.
    Nguyen, Hugo
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Jonsson, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    A heavily miniaturized submersible: a terrestrial kickoff2008Inngår i: Proceedings of ASTRA 2008, 2008, s. 1-9Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The vision of exploring extraterrestrial water findings employing a remotely operated submersible, as proposed by JPL/NASA for the investigation of the possible ocean underneath the frozen crust of Jupiter’s moon Europa, is now taking a step further into fulfilment. The Ångström Space Technology Centre has developed a sophisticated vehicle concept based on microtechnology for most of the navigational systems and payload systems. This enables a high function density, and a compact vehicle with a diameter of 50 mm and length of 200 mm, i.e. an overall size allowing the vehicle to be deployed through a borehole like that typical for arctic drilling.

    Here, the system architecture of the vehicle complying with the requirements on manoeuvrability, operational functions, and mission objectives is presented. In short, the vehicle in the first version will operate in deep and narrow waters, and will be equipped with a camera, sonar imaging system, an electronic tongue for chemical sampling, and a Conductivity-Temperature-Depth (CTD) sensor. Although the vehicle will be given certain autonomy in later versions, the first edition will rely on remote manual guidance. Commands for this, as well as power download, and data upload will be communicated through an optic fibre.

    The objective of this contribution is to present, for the first time, the status of the project including, briefly, the first results from miniaturized sonar, the vehicle bus design, and the design, realization and testing of the propulsion and attitude control systems differing in manoeuvrability, weight/volume, redundancy and efficiency.

  • 24.
    Nguyen, Hugo
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Jonsson, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Edqvist, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Sundqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Heavily Miniaturized Submersible – A Terrestrial Kickoff2008Inngår i: Heavily Miniaturized Submersible – A Terrestrial Kickoff, 2008, s. S14-01Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The vision of exploring extraterrestrial water findings employing a remotely operated submersible, as proposed by JPL/NASA for the investigation of the possible ocean underneath the frozen crust of Jupiter’s moon Europa, is now taking a step further into fulfilment. The Ångström Space Technology Centre has developed a sophisticated vehicle concept based on microtechnology for most of the navigational systems and payload systems. This enables a high function density, and a compact vehicle with a diameter of 50 mm and length of 200 mm, i.e. an overall size allowing the vehicle to be deployed through a borehole like that typical for arctic drilling.

    Here, the system architecture of the vehicle complying with the requirements on manoeuvrability, operational functions, and mission objectives is presented. In short, the vehicle in the first version will operate in deep and narrow waters, and will be equipped with a camera, sonar imaging system, an electronic tongue for chemical sampling, and a Conductivity-Temperature-Depth (CTD) sensor. Although the vehicle will be given certain autonomy in later versions, the first edition will rely on remote manual guidance. Commands for this, as well as power download, and data upload will be communicated through an optic fibre.

    The objective of this contribution is to present, for the first time, the status of the project including, briefly, the first results from miniaturized sonar, the vehicle bus design, and the design, realization and testing of the propulsion and attitude control systems differing in manoeuvrability, weight/volume, redundancy and efficiency.

  • 25.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A miniaturized optical communication system for microspacecraft2010Konferansepaper (Fagfellevurdert)
  • 26.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A highly integratable silicon thermal gas flow sensor2012Inngår i: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 22, nr 6, s. 065015-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal flow sensors have been designed, fabricated, and characterized. All bulk material in these devices is silicon so that they are integratable in silicon-based microsystems. To mitigate heat losses and to allow for use of corrosive gases, the heating and sensing thin film titanium/platinum elements, injecting and extracting heat, respectively, from the flow, are placed outside the channel on top of a membrane consisting of alternating layers of stress-balancing silicon dioxide and silicon nitride. For the fabrication, an unconventional bond surface protection method using sputter-deposited aluminum instead of thermal silicon dioxide is used in the process steps prior to silicon fusion bonding. A method for performing lift-off on top of the transparent membrane was also developed. The sensors, measuring 9.5 x 9.5 mm(2), are characterized in calorimetric and time-of-flight modes with nitrogen flow rates between 0 sccm and 300 sccm. The maximum calorimetric sensor flow signal and sensitivity are 0.95 mV and 29 mu V sccm(-1), respectively, with power consumption less than 40 mW. The time-of-flight mode is found to have a wider detectable flow range compared with calorimetric mode, and the time of flight measured indicates a response time of the sensor in the millisecond range. The design and operation of a sensor with high sensitivity and large flow range are discussed. A key element of this discussion is the configuration of the array of heaters and gauges along the channel to obtain different sensitivities and extend the operational range. This means that the sensor can be tailored to different flow ranges.

  • 27.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Infrared imaging of an integratable, robust thermal flow sensor with a thick silicon dioxide membrane and through-going silicon heat conductors2011Inngår i: 17th International Workshop on Thermal Investigations of ICs and Systems, 2011, s. 70-73Konferansepaper (Fagfellevurdert)
  • 28.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Lekholm, Ville
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Nguyen, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Development of a suspended, robust, thermally insulated micro chamber of thick silicon dioxide for microthrusters and micoreactors2011Inngår i: PowerMEMS 11 Technical digest: The 11th International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications / [ed] Young-Ho Cho, 2011, s. 62-65Konferansepaper (Fagfellevurdert)
  • 29.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Lotfi, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Berglund, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    A micromachined dual-axis beam steering actuator for use in a miniaturized optical space communication system2010Inngår i: Journal of Micromechanics and Microengineering, ISSN 0960-1317, E-ISSN 1361-6439, Vol. 20, nr 10, s. 105007-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The design, fabrication and evaluation of an electrothermally actuated micromachined beam steering device for use in a free-space optical communication system intended for use on micro-and nanospacecraft in kilometer-sized formations are presented. SU-8 confined in v-grooves is heated to create bending movement in two orthogonal directions for two-axial steering with large static bending angles and low actuation voltages. Standard MEMS processing is used to fabricate the devices with square mirror side lengths of 1, 3.5 and 5 mm. In addition, a method to prevent thermal damage to SU-8 during deep reactive ion etching has been successfully developed. Characterization shows optical scan ranges larger than 40 degrees in both directions with the maximum driving voltage of 16 V corresponding to a total power consumption of 1.14 W. Infrared imaging is used to investigate thermal cross-talk between actuators for the two scanning directions. It is found that a silicon backbone on the joint backside is crucial for device performance. Differences from expected performance are believed to arise from the SU-8 curing process and excessive heating during fabrication. A finite element method simulation is used to find the eigenfrequencies of the structures, and these are in good agreement with the measured frequency response.

  • 30.
    Palmer, Kristoffer
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Lotfi, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    Thornell, Greger
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrostrukturteknik.
    A micromachined dual-axis actuator for Use in a miniaturized optical communication system2008Inngår i: Proceeding of the International Astronautical Congress, Sep 29 - Oct 3, Glasgow, Scotland, 2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A micromachined beam-steering device for use in a miniaturized free-space optical communication system is presented. This device is part of a communication system intended for microspacecraft flying in kilometer-sized formations. Central to it, is a laser-reflecting mirror tiltable in two orthogonal directions using electrothermal actuators based on heating of a polymer confined in silicon v-grooves. The device is fabricated using standard microstructure technology. Successful experiments show a maximum mechanical scan range of 19º in two orthogonal directions. The voltages applied are below 100 V, and the power consumption is less than 2.4 W. Thermal coupling between orthogonal joints has been investigated with infrared imaging. The overall results are very promising, and improvement in the design and fabrication can be suggested.

  • 31.
    Yousef, H
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Cheng, Shi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Rydberg, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Hjort, Klas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Substrate integrated waveguides in flexible PCB2008Inngår i: IMAPS Advanced Technology Workshop on RF and Microwave Packaging, 2008Konferansepaper (Fagfellevurdert)
  • 32.
    Yousef, Hanna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Cheng, Shi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrovågs- och terahertzteknik.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Mikrosystemteknik.
    Substrate Integrated Waveguides (SIW) in a Flexible Printed Circuit Board for Millimeter Wave Applications2009Inngår i: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 18, nr 1, s. 154-162Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Substrate integrated waveguides (SIWs) are presented and demonstrated in a flexible printed circuit board (flex PCB) for application in the 77-81 GHz range. The vertical walls of the SIWs presented in this paper consist of multiple electrodeposited metallic wires. The diameters of these wires and the spacing between them are on the order of hundreds of nanometers. Hence, the walls can be seen as continuous metallic walls, and the leakage losses through them become negligible. In turn, the SIWs presented in this paper can operate at higher frequencies compared with previously presented structures that are realized with PCB fabrication processes. The attenuation of the SIWs is comparable to that of microstrip lines on the same sample. The SIWs are successfully demonstrated in a SIW-based slot antenna. The antenna gain along the z-axis (normal-to-plane) was found to be around 2.8 dBi at 78 GHz which is in agreement with the simulated values. [2008-0047]

  • 33.
    Öjefors, Erik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signalbehandling. Signals and systems.
    Kratz, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signalbehandling. Signals and systems.
    Rydberg, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signalbehandling. Signals and systems.
    Membrane antenna for silicon based 3D integrated microsystems2005Inngår i: MEMSWAVE 2005 Workshop, 2005Konferansepaper (Fagfellevurdert)
1 - 33 of 33
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf