基于MEMS的微槽冷却系统在微纳卫星热控中的应用
MEMS技术在微纳卫星的应用
Invited PaperMEMS for pico- to micro-satellitesH.R. Shea*Microsystems for Space Technologies Laboratory (LMTS)EPFL, Ecole Polytechnique Fédérale de Lausanne,Rue Jaquet Droz 1, CP 526, CH-2002 Neuchâtel, SwitzerlandABSTRACTMEMS sensors, actuators, and sub-systems can enable an important reduction in the size and mass of spacecrafts, first by replacing larger and heavier components, then by replacing entire subsystems, and finally by enabling the microfabrication of highly integrated picosats. Very small satellites (1 to 100 kg) stand to benefit the most from MEMS technologies. These small satellites are typically used for science or technology demonstration missions, with higher risk tolerance than multi-ton telecommunication satellites. While MEMS are playing a growing role on Earth in safety-critical applications, in the harsh and remote environment of space, reliability is still the crucial issue, and the absence of an accepted qualification methodology is holding back MEMS from wider use. An overview is given of the range of MEMS applications in space. An effective way to prove that MEMS can operate reliably in space is to use them in space: we illustrate how Cubesats (1 kg, 1 liter, cubic satellites in a standardized format to reduce launch costs) can serve as low-cost vectors for MEMS technology demonstration in space. The Cubesat SwissCube developed in Switzerland is used as one example of a rapid way to fly new microtechnologies, and also as an example of a spacecraft whose performance is only possible thanks to MEMS.Keywords: MEMS, spacecraft, satellites, nanosatellites, cubesats, space1.OVERVIEW OF MEMS APPLICATIONS IN SPACEIn 2008 the market for MEMS (MicroElectroMechanical Systems) devices was nearly $8 Billion according to Yole Développement [1]. MEMS encompass an enormous range of applications, from RF switching to projection display to inertial sensors to implantable pumps. Combining low mass, low power consumption, small volume and possible integration with control and sense electronics, MEMS seem ideal for space applications, where it costs approximately 10’000 $ to place one kg in low Earth orbit (LEO).Reliability is a key concern for spacecraft, in view of the very larger development costs, near impossibility of repair (the service missions to the Hubble Space Telescope are the notable exception), and limited launch slots. One major difference between operation on Earth and in Space is the radiation level [2]. Other space-specific reliability concerns are thermal cycling and thermal shocks, vibration and mechanical shock at launch and stage/heat shield separation, and operation in very high vacuum. The typical service life of a telecommunication satellite is 15 years, during which time the spacecraft must operate continuously and flawlessly. For this reason, and because of the need for radiation tolerance, new technologies are generally accepted in space applications only many years later than in consumer electronics, except for cases where a new technology is required for a mission, or allows dramatic performance enhancement or mass reduction. This was the case for instance for FPGAs and is now the case for MEMS.The fraction of the $8 Billion MEMS market for space is very small, and MEMS for use in space often have unique requirements. MEMS have been proposed for a number of space applications, as lighter and smaller replacement parts or as entire new systems [3][4][5], or as a means to provide affordable redundancy and hence improved operational reliability [6]. Few MEMS components have been flown in space. MEMS for space are currently either commercial off-the-shelf (COTS) parts such as accelerometers or gyroscopes that have been subjected to additional testing and qualification, or new MEMS devices that are crucial enabling technologies for science missions which cannot proceed without MEMS (such as the AFM on the Phoenix mission on Mars [7]). In the medium term MEMS technology will allow sub-systems (such as attitude determination, phased array antennas, Earth sensors, optical switches, low-thrust * herbert.shea@epfl.ch ; http://lmts.epfl.chMOEMS and Miniaturized Systems VIII, edited by David L. Dickensheets, Harald Schenk, Wibool Piyawattanametha Proc. of SPIE Vol. 7208, 72080M · © 2009 SPIE · CCC code: 0277-786X/09/$18 · doi: 10.1117/12.810997propulsion systems) to be reduced significantly in size and mass. In the longer run MEMS can enable new classes of extremely small, intelligent, self managing and relatively low-cost batch-produced picosatellites operating in constellations. Most MEMS devices currently under development for specific space applications are not intended for picosallites, principally because most satellites currently have masses larger than 100 kg. However pico and nanosatellites are the main users in space of COTS MEMS parts (pico and nanosats are also the main users in space of COTS microcontrollers, batteries, etc since the development budget of these small satellites often precludes using standard space grade components). Some of the more developed MEMS areas for space are listed below, and can also be found in [8].Inertial Navigation: accelerometers and gyroscopes are the most mature MEMS devices used in space, used to instrument launchers as well as rovers on Mars. Since these devices are available as COTS parts for commercial and military applications, it is likely that they can be re-qualified for space by de-rating (for one de-rating procedure see ref [14]). There have been several studies addressing COTS accelerometers for space [11][12][13]. COTS accelerometers have been shown to survive 1000 temperature cycles from -65°C to +150°C, as well as 30,000 mechanical shocks of 2,000 G. To measure microgravity on the GeneSat1 mission, model 1221 capacitive micromachined accelerometers from Silicon Designs Inc., Issaquah, WA, USA were flown in 2006 in low Earth orbit [15].RF Switches and Variable Capacitors: MEMS technologies enable the fabrication of very compact low-loss RF switches, as well as capacitors with a large tuning range. Such devices are just starting to be commercially available, for example from Radant MEMS [16] (Stow, MA, USA). RF switches were flown in space on the OPAL Picosats in 2000. They were stored in orbit for a year, and then successfully operated [17]. IMEC, in Leuven, Belgium, have led several studies into the reliability of RF MEMS for Space [18].Atomic Force Microscope: an AFM was one of the scientific instruments on the 2008 Phoenix mission to Mars [7][19]. The piezoresistive single crystal silicon based AFM operated flawlessly on Mars. The scanner and cantilevers of the AFM were not radiation hardened but its control electronics were. This is a good example of rapid acceptance of MEMS in space. The near-impossibility of making an AFM without MEMS technology, and the fact that a failure of the AFM would not compromise the mission, allowed MEMS technology to be much more readily accepted.Bio and Microfluidics: SU8 and other polymers, as well as Pyrex and silica can be used to fabricate micro-fluidic devices, including channels, nozzles and pumps. Such devices are principally being developed for medical or pharmaceutical (lab-on-a-chip) applications, and have been flow on the 25 cm long GeneSat1 in 2006 to study the development of E. Coli cells in microgravity [15] [31] as well as in a small micro-reactor for yeast cell studies on the Space Shuttle and could also eventually be used as part of a propulsion system.Bolometers: micromachining allows thermal isolation of small detectors, enabling both uncooled and cooled bolometer arrays to offer very high performance. Such devices are commercially available for earth-based IR detector applications.A MEMS bolometer from JPL/Caltech [10] is planned for the ESA/NASA Planck mission in 4-2009 to image the anisotropies of the Cosmic Background Radiation Field.Optical instrumentation: the NIR-Spec (Near InfraRed Spectrometer) on the James Webb Space Telescope (JWST) will use MEMS-based micro-shutters manufactured by NASA/GSFC, whose radiation testing at 60 K is reported in [20]. The JWST is expected to be launched in 2013. The MEMS-based microshutter allows important performance improvement and several orders of magnitude mass reduction compared to a conventionally mechanical shutter array.Optical Switching and Communication: The boom in optical MEMS between 1999 and 2002 led to the development of large optical switch matrices based on MEMS devices. There are ongoing European Space Agency (ESA) projects on the development and qualification methodology of such MEMS switches for space. There have been studies of COTS parts [21], but no devices have been flown.Louvers for thermal control: MEMS louvers were developed by the Johns Hopkins University and NASA using a polysilicon process, allowing the emittance of the spacecraft to be varied [22]. Launched in 2006 aboard NASA’s Space Technology 5 (ST5), they successfully operated as predicted.Propulsion: MEMS propulsion systems produce low thrust, from µN to at most 1 N. Such thrust levels can allow orbit maneuvers for small satellites, or attitude control and station keeping for larger satellites. There are several approaches to using MEMS for propulsion in space, reflecting the different propulsion technologies such as cold gas, hot gas, and electric propulsion. Electric propulsion allows reducing the amount of propellant required due to the high propulsionefficiency, but requires enough solar power to extract and accelerate the ions, often more power than available on very small satellites.One approach to miniaturizing an ion-thruster is to micromachine and integrate the electron source, gas handling, nozzle and other components, is reported in [23]. Another approach to integrated MEMS colloid thrusters is described in [24][25][26], where arrays of micromachined ion sources using ionic liquids as fuel are used to create highly modulable thrust. Yet another approach is to microfabricate arrays of explosive microthrusters which consist of micromachined cavities filled with solid propellant. A micromachined hotplate is bonded on top of each cavity to allow ignition of the microthrusters one at a time [27][28]. Finally, silicon machining has been used to fabricate compact cold gas thrusters consisting of bonded Si chips to form a reaction chamber and compact nozzle [29]. A good overview of micropropulsion for Cubesats can be found in [30]. A Cold Gas Microthruster (CGMT) from Marotta Scientific Controls was flown on NASA’s ST5 mission. More highly integrated cold-gas thrusters are expected to be flown in 2009. Formation flying missions such NASA & ESA’s Laser Interferometer Space Antenna (LISA) planned for 2019 may well use MEMS-based micro-propulsion.MEMS Device Flown? (mission)Estimated TRL of the MEMS forSpace applications Inertial Navigation(accelerometers, gyroscopes)Yes, almost routinely for NASA HighPressure sensor Yes, routine for launch vehicles High Magnetometer Yes (Cubesats)HighAFM (atomic force microscope)In 2008 (Phoenix)Medium- HighSun sensor In 2008 (Delfi 3C)Medium - HighMicro-fluidics Yes (3x Shuttle, and Genesat) MediumBolometer In 2009 (Planck)MediumOptical switching No Medium Propulsion (ion, cold gas, colloid, solidpropellant)In 2006 (ST5) MediumThermal control In 2006 (ST5)MediumRF switch and variable capacitor In 2000 (OPAL picosats)Low -MediumMEMS oscillator No Low - MediumAdaptive optics and MOEMS-based optical instruments No, planned for James Webb SpaceTelescope (2013)Low - MediumTable 1: Summary of which MEMS technologies have been flown, and rough estimate of Technology Readiness Level (TRL).2.CUBESATS, PICO AND NANOSATELLITESThe generally accepted definition [32] for pico-satellites is a spacecraft with a wet mass (i.e., mass including propellant) of 1 kg or less, nano-satellites have mass between 1 and 10 kg, and micro-satellites range from 10 to 100 kg. For comparison, a typical telecom satellite in Geostationary orbit (GEO) has a mass of 1000 to 5000 kg.Large satellites have long development times, of order 5 to 15 years. Smaller satellites can be developed much faster. Picosatellites and Nanosatellites are natural users of MEMS because they require very high levels of integration and miniaturization in order to fit data handling, communication, attitude determination and control, payload, structure, batteries and other subsystems in such a small volume. A short overview of recent pico and nanosatellites is given below. The Cubesat standard was defined in 1999 at the California Polytechnic State University, San Luis Obispo, CA and at Stanford University’s Space Systems Development Lab, Palo Alto, CA, as a means to provide affordable access to space, initially primarily for academic institutions. Cubesats are cubic satellites 10 cm on a side, with a mass of up to 1 kg. Detailed specifications can be found at [33]. Cubesats can also be built in a “triple” standard, 10 x 10 x 30 cm3, maximum mass of 3 kg. Single Cubesats are typically launched in groups of three, and Cubesats are generally “piggy-back” launches: the main customer of the launch vehicle chooses the orbit for its conventional-size satellites; once those main spacecraft are in orbit, the Cubesats are ejected from the launcher in a slightly different orbit to avoid any collision. There are no dedicated Cubesat launchers. Several companies offer Cubesat launch services, freeing the Cubesat builder from negotiations with the various launch providers as well as taking care of export control procedures.There are currently approximately 80 Cubesats under development, and 40 have been launched from a variety of American, Russian, Japanese, and Indian launch vehicles. The field is active, with 5 small companies offering kits and parts specifically for the Cubesat standard [34]. While Cubesats serve in large part to teach students about system engineering and about space systems, they are also ideal vehicles for proving in or testing novel technologies that are not yet acceptable for larger commercial missions because of a lack of flight history. It is a reasonable approach to use missions which can accept large risk (such as Cubesat missions) to prove in novel technologies, or to provide the first demonstration of space application of a technology that has been shown to be reliable on Earth. The main limitation of using Cubesats or other nanosats to increase the Technical Readiness Level (TRL) of MEMS components is the generally short life (less than 1 year typically) of these small satellites, which precludes learning how a MEMS device degrades after many years in space.For cost, lead time and availability reasons, Cubesats are generally built using commercial components, not space qualified or radiation tolerant parts. While using such parts may reduce the lifetime of Cubesats, it also means they are flying very recent technologies. The reliability of MEMS for space is discussed in [9][35] and the radiation sensitivity of MEMS to radiation is reviewed in [8]. Despite their lack of radiation shielding, radiation is generally not a major concern for Cubesats and most nanosats because they operate in low-Earth orbit, and have a lifetime probably limited by the degradation of their rechargeable batteries rather than the 3 to 15 krad they will receive per year.The use of MEMS in Cubesats has focused on their use in the attitude determination subsystem: inertial sensors (gyroscopes), magnetometers, and optical sensors such as sun sensors and star trackers. Magnetometers and gyroscopes are typically COTS devices, while sun sensors and star trackers are space specific developments. These are presented in the following section.There are several nanosatellites in orbit. For example, the OPAL 13.5 kg satellite launched in 2000 held two picosats, each with an RF MEMS switch from Rockwell Scientific on board. The two picosats were ejected once OPAL was in orbit. One goal was to observe how MEMS devices could operate after storage in space. The picosats were turned on after one year in LEO orbit, and operated correctly [17].MEPSI, a MEMS-based PICOSAT inspector, is a series of picosats developed by Aerospace Corp for DARPA, and have been launched in tethered pairs from the cargo bay of the Space Shuttle on flights STS -113 in 2002 and STS-116 in 2006. They have a combined mass of 3.5 kg, and dimension of 10 x 10 x 12.5 cm3. The ones flown in 2006 have a 5 thruster cluster system using a MEMS pressure transducer. Figure 1 is a NASA photo showing two tethered MEPSI satellites being launched from the Shuttle cargo bay.NASA’s Space Technology 5 (ST5) was a set of three 25 kg spacecraft, launched in 2006, that operated as a constellation and demonstrated several new technologies, including the MEMS louvers mentioned above, and a cold gas thruster using MEMS components.Figure 1. Two MEPSI nano-satellites just after ejection from the cargo-bay of the Space Shuttle on mission STS-116 in December2006. Photo credit: NASA.3.MEMS-BASED ADCS ON CUBESATSThe Attitude Determination and Control System (ADCS) is the subsystem where MEMS are playing the biggest role in Cubesats, because MEMS sensors offer high performance, high reliability, and low-power consumption, and because this is field where highly reliable commercial devices are available at low cost (a few dollars per axis for accelerometers, less than $100 for gyroscopes). Propulsion (which may be part of the ADCS system if the propulsion serves to orient the spacecraft) is also an active field.The University of Illinois’s dual-cube cubesat ION (Illinois Observing NanoSatellite) included a microvacuum arc thruster (µVAT) [37]. The system consists of 4 micro-thrusters allowing two-axis rotation. Sadly ION was destroyed along with 11 other Cubesats when the launch vehicle exploded in 2006 only 86 seconds after lift-off.Delft University in the Netherlands is planning to fly a MEMS-based cold gas thruster developed by TNO, TU Delft, and U Twente on its triple-format (3 liter volume) Cubesat Delfi-n3Xt [38], with launch planned for 2010. Here the MEMS technology (nozzles, vales) and cold-gas generation allows very important mass and volume reduction, enabling a Cubesat to have propulsion, thus greatly increasing the range of missions which Cubesats can carry out.A good example of the use of commercial MEMS devices on a Cubesat is the Danish Cubesat AAUSAT-II, launched in 2008, carrying 6 Analog Devices Single Chip Yaw Rate Gyroscopes (model ADXRS401), and one 3-axis magnetometer model HMC1053 from Honeywell as part of the attitude determination system. The sensors operated as expected in orbit.SwissCube [39] is a Cubesat developed in Switzerland, lead by the EPFL Space Center, with launch planned for March 2009. It will image the atmospheric airglow, which is light emitted most strongly at 762 nm from an oxygen layer 85 km to 100 km in altitude, as illustrated in Figure 2. To take pictures of the airglow, SwissCube must be pointed at the limb of the Earth, and requires attitude determination accurate to better than 1°. The only way to obtain the required performance within the mass, volume and power budgets was to use MEMS components. The goal is not to prove in the MEMS components for their own sake, but rather MEMS are unavoidable for SwissCube because high-performance attitude determination on Cubesat missions is only possible with MEMS technology.The MEMS gyroscope selected for SwissCube was the ADXRS614 from Analog Device because of its low power consumption and a high sensitivity for low rotation rates. The gyroscopes are needed principally during eclipses (approximately 30% of each orbit is in eclipse). Three gyroscopes are mounted at 90° to each other, one on the main ADCS printed circuit board, and two on smaller board mounted perpendicularly to the ADCS board, as shown in Figure3.The same 3-axis Honeywell magnetometer (model HMC1053) was selected as for the AAUSAT-II mission. Knowing the position of the satellite in its orbit, and the local vector of the magnetic field allows the determination of the relative orientation of the satellite with respect to the Earth.When SwissCube is not in the shadow of the earth, the attitude determination system is completed by another set of MEMS sensors, micromachined Sun sensors developed and fabricated at the Danish Technical University (DTU). Very similar sun sensors, also from DTU, were flown on the Danish Cubesat DTUSat1 in 2003. Unfortunately DTUSat1 did not operate in orbit for reasons that could not be determined. These sun sensors are photodiodes with micromachined slits that each provide two analog output currents, each proportional to one of the two angles between the plane of the sun sensor and the vector to the sun [40]. Six sun sensors are used, one on each face of the spacecraft, as shown in Figure4. If the position of the sun with respect to the Earth is known (e.g. from the time and from the orbit parameters), the orientation of the satellite with respect to the Earth can be readily obtained from the angle of one satellite face to the sun vector.Figure 2: Artist’s impression of SwissCube in orbit. The airglow can be seen at the green arc above the Earth. Figure 3: part of the ADCS board on SwissCube. The perpendicular mounts for the two of the three MEMS gyroscopesare clearly visible.Figure 4: One side of SwissCube (10x10 cm 2). At the center of each face, between the top and bottom solar panels, the MOEMS sun sensor from DTU can be seen (just to the right of the centralhole)Figure 5: Optical micrograph of one of DTU MOESM 2-axis sun sensors [DTU]CONCLUSIONSMEMS technologies are increasingly used in space. They are routinely flown in Cubesats, small 1 kg satellites, where high levels of risk are accepted, and because operation without MEMS entails enormous performance penalties for suchsmall and highly integrated systems. The attitude determination subsystem is currently the part of the pico and nanosatellites that is based on MEMS sensors. Future Cubesats will rely even more heavily on MEMS technology. Picosatellites and nanosatellites have much smaller mass and power budgets than large multi-ton commercial satellites, and hence, along with scientific satellites, are the early adopters of MEMS in space. Scientific missions are starting to accept to MEMS components, both because of their high performance, as well as because of important mass and power savings.MEMS qualification procedures and radiation-tolerant control electronics for MEMS are progressing quickly, and need to mature further before MEMS solutions are widely accepted in commercial spacecraft.ACKNOWLEDGEMENTSH.S. thanks R. Krpoun of the EPFL-LMTS, G. Röthlisberger and M. Noca of the EPFL Space Center and the entire SwissCube team for helpful discussions.REFERENCES[1]http://www.yole.fr/pagesAn/products/mis.asp[2]Koons, H. C., J. E. Mazur, R. S. Selesnick, J. B. Blake, J. F. Fennell, J. L. Roeder, & P. C. Anderson, The Impact ofthe Space Environment on Space Systems, Aerospace Corp. report no. TR-99(1670)-1, 20 July 1999[3]Microengineering Aerospace Systems, H. Helvajian, ed, The Aerospace Press, 1999[4]MEMS and Microstructures in Aerospace Applications, Robert Osiander, M. 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Buchner et al., IEEE Trans. onNuclear Science, vol.54, no. 6, p 2463, 2007[21]“Reliability Assessment and Lifetime Testing with Micro-Mirrors”, S. Manhart et al., 4th Round Table on MNT forSpace. 20-22 May 2003, ESTEC, Noordwijk, Netherlands. Available at: https:///public/mnt4/[22]M. Beasley et al., “MEMS thermal switch for spacecraft thermal control”, Proc. SPIE, Vol. 5344, 98 (2004);DOI:10.1117/12.530906[23]“Micropropulsion for small spacecraft: a new challenge for field effect electric propulsion and microstructuredliquid metal ion sources”, by J. Mitterauer. Surface and Interface Analysis, Vol. 36, Issue 5-6 , p. 380 - 386 (2002) [24]R. Krpoun et al, “Microfabrication and test of an integrated colloid thruster” 2008 Proc. 21st IEEE Int. Conf. onMicro Electro Mechanical System (Tucson, USA) 0234 pp 964–967[25] “Microfabricated Electrospray Thrusters for Spacecraft Propulsion”, R. Krpoun, Ph.D. thesis, Ecole PolytechniqueFédérale de Lausanne, Switzerland, No. 4255 (2008).[26] B. 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Stenmark, Sensors and Actuators A (Physical), A97-98:587-98, April 2002.[30]Mueller, J.: “Thruster Options for Microspacecraft: A Review and Evaluation of Existing Hardware and EmergingTechnologies”, AIAA paper 97-3058, 33rd Joint Propulsion Conference and Exhibit, Seattle, WA, July 6-9, 1997 [31]“Integrated System To Analyze The Genetic Effects Of The Space Environment On Living Cells In Culture:Genesat”, by A. J. Ricco1 et al., p. 527, Proceedings of the 9th International conference on miniaturized systems for Chemistry and Life Science (TAS 2005), Boston, October 2005[32]/SSHP/sshp_classify.html[33][34]/pages/suppliers.php[35]“Reliability of MEMS for space applications”, H. Shea, Proc SPIE (6111), 61110A, 2006, Photonics West 2006[36]http://www.prismasatellites.se/?sid=902[37]“MicroVacuum Arc Thruster Design for a Cubesat class Satellite”, F. Ryasanek et al., 16th Annula US Conferenceon Small Satellites, SSC02-I-2[38]http://www.n3xt.delfispace.nl/[39]http://swisscube.epfl.ch[40]M. 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一种微型槽道热管的性能分析与试验研究
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证 ，最终确定 了较为理想的槽道几何参数。研究结果表明：该种微 型热管的极限传热能力为 ４ ． ７ ７ ｗ． ｍ， 极 限 负载 下的轴 向 温度 均 匀性优 于土 ０ ． ５ ℃。
关键 词 微 型热 管 梯 形槽 道 极 限传 热 能力 试验 研 究
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摘 要 槽道热管是航 天器较为常用的一种热控产品，其 中截面特征尺寸小于 ５ ｍ ｍ 的微型槽道热 管主要用于空间光学遥感器 Ｃ Ｃ Ｄ 器件 的散热 ，在设计 、加工等环节均具有较 高的技术难度。文章设计 了一种 ５ ｍ ｍ× ４ ｍ ｍ 矩形截 面、内部槽道为梯形的微型热管，对热管传热性能进行 了理论计算和试验验
航天返回与遥感
基于MEMS技术的新型微冷却方式
讨了Байду номын сангаас通道平板堆叠式结构冷却器的散热模型 [3] 。 目前在研的新型微冷却器方案有数十种 ,按照制冷机理 ,可
以分为两大类 :热电冷却和强制液冷 。热电冷却算不上是一项 新型技术 ,它早已被用于在体积和重量上有较高限制的航空航 天领域 ,但由于其自身散热机理的限制 ,散热功率较低 ,目前的 研究主要是侧重于 MEMS 工艺的引入 ,使其小型化 ,并在有限的 范围内提高散热功率 。强制液冷方面的研究相对比较活跃 ,其 基本结构如图 1 所示 。主体由散热板 、泵和换热器构成 。散热 板吸收芯片上的热量 ,通过液体循环将热量输送到换热器 ,再由 换热器将热量传给外界 。水箱和过滤器属于辅助装置 。各种方 案的不同之处主要是散热板和泵 。泵可采用普通泵和微泵 。对 于台式电脑 ,空间限制不是太苛刻 ,可用普通泵 。但有些场合空 间有限 ,如笔记本电脑 ,就须考虑用微泵 。Cooligy 公司的微冷却 器 ,就采用了电渗泵 。微泵也是 MEMS 的一个重要研究领域 ,文 中不作讨论 ,可查阅参考文献[4 ] 。散热板是微冷却器的核心部 件 ,也是产生实质性差异和最具创新价值的一个部件 。
Novel Microcooling Methods Based on MEMS Technology
HE Ye ,L I Lei2min ,YANG Tao (School of Information and Control Engineering ,Southwest University of Science and Technology ,Mianyang 621010 ,China)
under mass manufacturing were proposed as merits of the novel microcooling methods based on the MEMS technology ,including mi2
纳型卫星热控系统设计与仿真
第18卷第1期 系统 仿 真 学 报© V ol. 18 No. 12006年1月 Journal of System Simulation Jan.， 2006纳型卫星热控系统设计与仿真丁延卫1,2，付俊明2，尤 政2（1.中国科学院 光电研究院，北京 100080；2.清华大学 精密仪器与机械学系，北京 100084）摘 要：现代微小卫星是当前航天技术发展的重要方向之一，热控分系统的功能是为星上仪器设备提供合适的温度环境。
针对一颗纳型卫星，介绍其功能和构成。
以获得最佳热耦合机制为目标，对纳型卫星本体及各分系统进行了全被动热控系统设计。
通过I-DEAS TMG 软件，建立卫星热分析模型，对卫星的在轨稳态和瞬态温度状态上进行了仿真分析。
仿真结果满足卫星总体要求，表明所提出的热设计思想和所采取的热设计措施可行。
关键词：纳型卫星；热设计；仿真；热耦合中图分类号：TP391.9 文献标识码：A 文章编号：1004-731X (2006) 01-0169-04Design and Simulation for Thermal Control System of NanosatelliteDING Yan-wei 1,2, FU Jun-ming 2, YOU Zheng 2(1.Academy of Opto-electronics, The Chinese Academy of Sciences, Beijing 100080, China; 2.Department of Precision Instruments and Mechanics, Tsinghua University, Beijing 100084, China)Abstract: Modern microsatellite and small satellite is one of important aspects of space technology development nowadays, and its thermal control system is to provide appropriate temperature environment for instruments and equipments. The structure and function of a nanosatellite were introduced. Under the optimal thermal coupling mechanism, all-passive thermal design was carried out for nanosatellite system and subsystems. By I-DEAS TMG software, thermal model of the nanosatellite was founded, and the on-orbit steady and transient temperature distributions of nanosatellite were simulated. Temperature data met the need of the mission. Results show that the idea and measures of thermal design for nanosatellite are feasible.Key words: nanosatellite; thermal design; simulation; thermal coupling引 言现代微小卫星已经不是简单的卫星小型化，而是依托高新技术、采用一体化、集成化、模块化、商用器件化以及功能软件化等全新的设计思想和概念、以高“功能密度”为核心的系统小型化。
MEMS技术在微流控芯片中的应用
MEMS技术在微流控芯片中的应用近年来，激光技术、微纳加工技术、生物传感技术等一系列新兴技术的迅速发展，推动微流控芯片技术不断取得新的进展。
微流控芯片是一种将微小液滴、细胞、粒子等进行微小操作的芯片，已经在药物筛选、病毒检测、细胞捕获和分离等多个领域得到应用。
其中，MEMS技术是微流控芯片中不可或缺的技术之一，本文将探讨MEMS技术在微流控芯片中的应用。
一、MEMS技术在微流控芯片中的基本原理MEMS（Micro-Electro-Mechanical System）技术是指采用微电子加工技术制造微小的机械、电子、光学和磁学元件或系统的技术。
在微流控芯片中，MEMS技术主要用于制造微型流体控制器件，如微型泵、微型阀门、微通道等。
通过MEMS制造的微流体控制器件，可以在微小尺度内实现精确灵活的流体操控和分析。
以微型泵为例，其原理是利用电压控制微小压电膜的膨胀和收缩，从而产生微流体引导和输送的效果。
而微型阀门则利用电极控制膜片的抬升和下压，从而实现流体的开关控制。
通过MEMS技术的微流体控制器件，可以实现精确的微小流体操作和分析，为微流控芯片的应用打下坚实的基础。
二、MEMS技术在微流控芯片中的应用领域1.生物学应用MEMS技术在生物学应用方面的威力凸显。
通过MEMS技术制造微型通道、微型泵和微型阀门，可以实现微小液滴、细胞、粒子等的分离、操控和检测。
同时，MEMS技术也可以制造微型生物芯片，实现分子检测、蛋白质分析、细胞分离等多项生物实验。
2.医学应用MEMS技术在医学应用中得到广泛应用。
微流控芯片可以显著提高药物筛选的效率，同时也能对药物对病原微生物生成的影响进行研究。
针对疾病诊断方面，可以通过微流控芯片进行肿瘤细胞检测、糖尿病病人血糖监测等，为临床医学提供更为精准的检测手段。
3.环境应用MEMS技术在环境应用领域的应用正在不断拓展。
利用微流控芯片制备环境检测芯片，可以实现对污染物的迅速监测和分析。
微纳系统微区感应加热技术的研究进展———
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基于MEMS的微介电液滴冲击冷却系统
基于MEMS的微介电液滴冲击冷却系统
郑凌云;应济
【期刊名称】《机电工程》
【年(卷),期】2006(023)008
【摘要】热控制是集成电路设计中需要解决的关键问题.随着特征尺寸以及封装密度的增加,目前的封装冷却技术将很快不能适应.介绍了基于MEMS的微介电液滴冲击冷却系统,用于集成芯片的冷却,并提出了相应的实验平台.
【总页数】3页(P21-23)
【作者】郑凌云;应济
【作者单位】浙江大学,机械工程系,浙江,杭州,310027;浙江大学,机械工程系,浙江,杭州,310027
【正文语种】中文
【中图分类】TN305.94
【相关文献】
1.基于MEMS的微槽冷却系统在微纳卫星热控中的应用 [J], 邵宝东;孙兆伟
2.MEMS微悬臂梁在冲击下的粘附失效预测 [J], 王佩瑶;唐洁影;余存江;恩云飞;师谦
3.MEMS微悬臂梁在冲击下的粘附失效预测 [J], 王佩瑶;唐洁影;余存江;恩云飞;师谦
4.磷脂微滴囊泡化的介观模拟 [J], 徐蕊;王子璐;何学浩
5.MEMS微悬臂梁在冲击环境下的可靠性 [J], 吕劲楠;唐洁影
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应用MEMS技术加快微小卫星及微卫星的发展_谭晓昀
应用MEMS技术加快微小卫星及微卫星的发展_谭晓昀应用MEMS技术加快微小卫星及微卫星的发展谭晓昀刘晓为(哈尔滨工业大学M EM S中心哈尔滨150001)摘要介绍了M EM S技术的重要性及在微小卫星及微卫星上的应用情况和发展趋势。
关键词M EM S 小卫星微卫星Development of Small satellite and Micro-satellite Speed up By MEMS Tech-nologyT an Xiaoyun Liu Xiaow ei(M EM S Center,H aer bin I nsitute of T echnology,H aer bin150001,China)Abstract It int roduced t he import ance of t he M EM S t echnology as w ell as its trend in development and the brief situat ions in applicat ion about small sat ellit e or micro-satellit e.Key words M EM S Small satellit e M icro-satellit e1 引言由于M EM S技术的发展,为微小卫星概念的实现提供了技术手段,卫星的微小化日益受到重视。
微小卫星采用集成化、模块化等新的设计方法,综合应用微电子、微机械、新材料、新能源和精密加工等新技术,使其一体化和功能密度高成为可能。
微小卫星的突出优点是体积小、成本低,研制周期短,风险小,应用领域广,发射方式灵活。
可以有效和快速地执行民用和军事任务。
由于其特点,结合M EM S技术,将使微小卫星的设计、制造和运行都发生深刻的变化。
有人按重量将卫星分为7种如表1。
表1kg种类大卫星小卫星微小卫星微卫星纳卫星皮卫星飞卫星重量>1000500～1000100～50010～1001～100.1～1<0.1为使微小卫星成为现实,美国空军研究实验室提出了六项关键技术[1]:轻型太阳能电池阵列、柔性集成供电和信号系统、多功能结构、超高密度电路、微机电系统、轻型大光学系统。
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ｒｑ ｉ ｍｅ ｅ ｎ ｅ ｈ ｃ ｏ ｈ ｎ ｅ ｏ ｌ ｙ ｔ ｍ ｗａ ｐ ｌ ｄ ｔ ｈ ｔ ｅ ｍａ ｏ ｔｏ ｉ ｉ ｏ ｎ ｎ ａ ｅｌ ｅ ｗａ ｎ ｓ ａ ｐ ｉ ｏ ｔ ｅ ｈ ｒ ｌ ｃ ｎ ｒ ｌ ｎ ｍ ｃ ／ ａ ｏ ｓ ｔ ｌｔ ｓ ｅ ｒ ｉ ｄ ｓ ｕ ｓ ｄ Ｔｈ ｒ ｐ ｒｙ ｏ ｙ ｒ ｕｃ ｍｅ ｈ ｎ ｃ ｎ ｅ ｔ ｔａ ｓｅ ｉ ｙ ｂ ｌ ｅ ｈ ｅｆ ｒ ａ ｃ ｆ ｍｉｒ ｃ ａ ｎ ｌ ｉ ｓｅ ． ｃ ｅ ｐ ｏ ｅ ｔ ｆ ｈ ｄ ａ ｉ ｃ ａ ｉ ａ ｄ ｈ ａ ｒ ｎ ｆ ｒ ｗｈ ｃ ｓ ｍ ｏｉ ｄ ｔ ｅ ｐ ｒｏ ｓ ｈ ｚ ｍ ｎ ｅ ｏ ｃ ｏ ｈ ｎ ｅ ｃ ｏｉ ｇｓ ｓｅ ｏ ｌ ｙ ｔ ｍ． Ｔｈ ｈ ｏ ｅ ｉ ｌａ ａ ｙ ｉ ａ ｄ ｎ ｍｅ ｉ ｌｓ ｎ ｅ ｔ ｅ ｒ ｔ ａ ｎ ｌ ｓ ｎ ｕ ｒ ａ ｉ ｌｔ ｎ ｒｓ ｌ ｓ ｏ ｄ ｔ ａ ｈ ｃ ｏ ｈ ｎ ｅ ｃ ｏ ｉ ｇ ｓ ｔｍ ｃ ｓ ｃ ｍｕ ａ ｉ ｅ ｕｔ ｈ ｗｅ ｈ ｔ ｔ ｅ ｍｉｒｃ ａ ｎ ｌ ｏ ｌ ｙ ｅ ｏ ｎ ｓ
Ｓ ＨＡＯ ａ － ｏ ｇ，Ｓ Ｂ ｏｄ ｎ ＵＮ ｈ ｏ ｗｅ Ｚ ａ－ ｉ （ ｅｅｒｈＩｓｉ ｔ ｏ ａｅｉ ｅｈ ｏ ｇ ，Ｈ ｒｉ ｎｔｕｅ ｆ ｅｈ ｏ ｇ ， ｒｉ ｉｎｊ ｎ ５ ０ ０ Ｃ ｉ ） Ｒ ｓａｃ ｎｔｕｅ ｆ ｔ ｌｅＴ ｃｎｌ ｙ ａｂｎＩｓｉ ｔ ｏ ｃ ｎｌ ｙ ＨａｂｎＨｅｏ ｇａ ｇ１０ ８ 。 ｈｎ ｔ Ｓ ｌｔ ｏ ｔ Ｔ ｏ ｌ ｉ ａ
ｔ ｅ ａ ｅ ｉｔｎ ｅｗｏ ｌ ｒ ｖｄ ｏ ｄ ｐ ｒ ｒ ａ ｃ ｆｔ ｅ ｉｌｐ ｓ ｉｇ ｕ ｄ ｒｔ ｅ ｃ ｎ ｉ ｏ ｆ ｍａｌ ｕ ｏ ｒ ｈ ｒ ｌ ｓ ｓａ ｃ ｕｄ ｐ ｏ ｉ ｅｇ ｏ ｅ ｆ ｍ ｎ ｅｏ ｈ ｍ ａ ａ ｓ ｎ ｅ ｈ ｏ ｄ ｔ ｎ ｏ ｍ ｒ ｏ ｎ ｉ ｓ ｌ ｐ ｍｐ ｐ ｗｅ ． Ｋｅ ｗｏ ｄ ： ｃｏ ｎ ｎ ｔｌ ｔ ；Ｔｈ ｒ ａ ｏ ｔ ｌ ｓ ｓ ｅ ；Ｍ ｉｒ － ｌ ｔｏ ｍｅ ｈ ｎ ｃ ｌｓ ｓｅ ；Ｍ ｉｒ ｃ ａ ｎ ｌ ｃ ｏ ｉｇ ｙ ｒ ｓ Ｍｉｒ ／ ａ ｏ ｓ ｅｌ ｅ ａ ｉ ｅ ｍ ｌｃ ｎ ｒ ｙ ｔｍ ｏ ｃ ｏ ｅｅ ｒ ｃ ａ ｉ ｙ ｔｍ ｃ ａ ｃｏ ｈ ｎ ｅ ｏ ｌ ｎ
Ａ ｓｒ ｃ ： ｅｒｓ ａ ｃ ｎ ｍｉｒ ｃ ａ ｎ ｌｃ ｏｉ ｇ ｓ ｓ ｅ ｂ ｓ ｄ ｏ ＥＭ Ｓ ｗａ ｎ ｒ ｄ ｃ ｄ ｉ ｈ ｓ ｐ ｐ ｒ ｂ ｔａ ｔ Ｔｈ ｅｅ ｒ ｈ ｏ ｃ ｏ ｈ ｎ ｅ ｏ ｌ ｙ ｔ ｍ ａ ｅ ｎ Ｍ ｎ ｓ ｉｔｏ ｕ ｅ ｎ ｔ ｉ ａ ｅ ．Ｔｈ ｐ ｃａ ｅ ｓ ｉｌ ｅ
维普资讯
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ＡＥＲ０Ｓ ＰＡＣＥ
Ｓ ＨＡＮ ＧＨＡＩ
文章 埔 号 ：０６１ ３ （０ ６ ０ ０ ４０ １０ ６０ ２ ０ ）４０ ３ ５
基于 ＭＥ ＭＳ的微槽 冷却 系统在 微 纳 卫 星 热控 中 的应 用