Bubble actuation by electrowetting-on-dielectric (EWOD) and its applications: A review

Article

Abstract

This paper reviews the principles, operations, and applications of bubble-based electrowetting-on-dielectric (EWOD). EWOD has proved to be an efficient tool in digital microfluidics that employs discrete droplets, and various applications that use the principles of EWOD have been developed from lab-on-a-chip to optical systems. Similar to its use with droplets, EWOD can also be applied to gaseous bubbles. This review begins with a discussion of the principles of EWOD for a bubble on an electrode covered with a hydrophobic dielectric layer. It then addresses EWOD actuation and the transportation of a bubble in an aqueous medium, along with a physical explanation of bubble motion. The operation of EWOD is then extended to the on-chip creation/elimination and splitting of bubbles. In particular, micro-mixers and pumps are discussed as potential applications of these operations. Unlike droplets, bubbles can be easily oscillated by external excitation, which provides additional functionalities. By integrating EWOD with external excitation, a number of new advanced applications are introduced, including the capture/separation of particles and the propulsion of objects. In these advanced operations, cavitational microstreaming flows and acoustic radiation forces are mainly responsible for the physical mechanisms. This paper also discusses these advanced operations along with their underlying physics. It is expected that in addition to bubble oscillation, other bubble actuation modes will create new functionalities and new potential applications.

Keywords

Microfluidics Lab-on-a-chip Bubble dynamics Cavitational microstreaming 

Nomenclature

ρ

fluid density

μ

fluid dynamic viscosity

V

mean fluid velocity

L

characteristic length

θ

contact angle under an applied electrical potential

θe

equilibrium contact angle

V

electrical potential

ɛ

permittivity of a dielectric layer

γ

interfacial tension

t

thickness of a dielectric layer

θR

contact angle on the right side of a bubble

θL

contact angle on the left side of a bubble

θadv

advancing contact angle

θrec

receding contact angle

w

width of a bubble base

R

radius of a bubble

Fdriving

bubble driving force

Ψ

streaming function of a cavitational streaming flow

ɛ

amplitude of bubble oscillation normalized by a radius of a bubble

ω

angular frequency of an applied acoustic wave

r

distance from a bubble center

Δϕ

phase shift between volume and translational oscillations

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References

  1. 1.
    Whitesides, G. M., “The origins and the future of microfluidics,” Nature, Vol. 442, No. 7101, pp. 368–373, 2006.CrossRefGoogle Scholar
  2. 2.
    Fair, R. B., “Digital microfluidics: is a true lab-on-a-chip possible?” Microfluidics and Nanofluidics, Vol. 3, No. 3, pp. 245–281, 2007.CrossRefGoogle Scholar
  3. 3.
    Cho, S. K., Moon, H. J. and Kim, C. J., “Creating, transporting, cutting, and merging liquid droplets by electrowetting-based actuation for digital microfluidic circuits,” Journal of Microelectromechanical Systems, Vol. 12, No. 1, pp. 70–80, 2003.CrossRefGoogle Scholar
  4. 4.
    Haeberle, S. and Zengerle, R., “Microfluidic platforms for labon-a-chip applications,” Lab on a Chip, Vol. 7, No. 9, pp. 1094–1110, 2007.CrossRefGoogle Scholar
  5. 5.
    Hong, J. W. and Quake, S. R., “Integrated nanoliter systems,” Nature biotechnology, Vol. 21, No. 10, pp. 1179–1183, 2003.CrossRefGoogle Scholar
  6. 6.
    Jakeway, S. C., Mello, A. J. d. and Russell, E. L., “Miniaturized total analysis systems for biological analysis,” Fresenius Journal of Analytical Chemistry, Vol. 366, No. 6–7, pp. 525–539, 2000.CrossRefGoogle Scholar
  7. 7.
    Cho, S. K. and Moon, H., “Electrowetting on dielectric (EWOD): New tool for bio/micro fluids handling,” The BioChip Journal, Vol. 2, No. 2, pp. 79–96, 2008.Google Scholar
  8. 8.
    Beebe, D. J., Mensing, G. A. and Walker, G. M., “Physics and applications of microfluidics in biology,” Annu. Rev. Biomed. Eng., Vol. 4, No. 1, pp. 261–286, 2002.CrossRefGoogle Scholar
  9. 9.
    Purcell, E. M., “Life at low Reynolds number,” American Journal of Physics, Vol. 45, No. 1, pp. 3–11, 1977.CrossRefMathSciNetGoogle Scholar
  10. 10.
    Burgreen, D. and Nakache, F. R., “Electrokinetic Flow in Ultrafine Capillary Slits,” Journal of Physical Chemistry, Vol. 68, No. 5, pp. 1084–1091, 1963.CrossRefGoogle Scholar
  11. 11.
    Holmes, D., Green, N. G. and Morgan, H., “Microdevices for Dielectrophoretic Flow-Through Cell Separation,” Engineering in Medicine and Biology Magazine, Vol. 22, No. 6, pp. 85–90, 2003.CrossRefGoogle Scholar
  12. 12.
    Klingner, A., Buehrle, J. and Mugele, F., “Capillary bridges in electric fields,” Langmuir, Vol. 20, No. 16, pp. 6770–6777, 2004.CrossRefGoogle Scholar
  13. 13.
    Morgan, H. and Green, N. G., “AC Electrokinetics: colloids and nanoparticles,” Research Studies Press, 2003.Google Scholar
  14. 14.
    Patankar, N. A. and Hu, H. H., “Numerical Simulation of Electroosmotic Flow,” Analytical Chemistry, Vol. 70, No. 9, pp. 1870–1881, 1998.CrossRefGoogle Scholar
  15. 15.
    Prins, M. W. J., Welters, W. J. J. and Weekamp, J. W., “Fluid control in multichannel structures by electrocapillary pressure,” Science, Vol. 291, No. 5502, pp. 277–280, 2001.CrossRefGoogle Scholar
  16. 16.
    Rice, C. L. and Whitehead, R., “Electrokinetic Flow in a Narrow Cylindrical Capillary,” Journal of Physical Chemistry, Vol. 69, No. 11, pp. 4017–4024, 1965.CrossRefGoogle Scholar
  17. 17.
    Welters, W. J. J. and Fokkink, L. G. J., “Fast electrically switchable capillary effects,” Langmuir, Vol. 14, No. 7, pp. 1535–1538, 1998.CrossRefGoogle Scholar
  18. 18.
    Mugele, F. and Baret, J. C., “Electrowetting: From basics to applications,” Journal of Physics-Condensed Matter, Vol. 17, No. 28, pp. R705–R774, 2005.CrossRefGoogle Scholar
  19. 19.
    Chung, S. K., Zhao, Y. and Cho, S. K., “Electrowetting-On-Dielectric (EWOD) Microfluidic Devices,” Lab on a Chip (LOC) Technologies and Applications, Edited by Keith E. Herold and Avi Rasooly, Horizon Scientific Press and Caister Academic Press, pp. 211–229, 2009.Google Scholar
  20. 20.
    Kang, K. H., “How electrostatic fields change contact angle in electrowetting,” Langmuir, Vol. 18, No. 26, pp. 10318–10322, 2002.CrossRefGoogle Scholar
  21. 21.
    Zeng, J. and Korsmeyer, T., “Principles of droplet electrohydrodynamics for lab-on-a-chip,” Lab on a Chip, Vol. 4, No. 4, pp. 265–277, 2004.CrossRefGoogle Scholar
  22. 22.
    Collet, P., De Coninck, J., Dunlop, F. and Regnard, A., “Dynamics of the contact line: Contact angle hysteresis,” Physical Review Letter, Vol. 79, No. 19, pp. 3704–3707, 1997.CrossRefGoogle Scholar
  23. 23.
    Huh, D., Tkaczyk, A. H., Bahng, J. H., Chang, Y., Wei, H. H., Grotberg, J. B., Kim, C. J., Kurabayashi, K. and Takayama, S., “Reversible switching of high speed air liquid two phase flows using electrowetting assisted flow pattern change,” Journal of the American Chemical Society, Vol. 125, No. 48, pp. 14678–14679, 2003.CrossRefGoogle Scholar
  24. 24.
    Mugele, F., Klingner, A., Buehrle, J., Steinhauser, D. and Herminghaus, S., “Electrowetting: a convenient way to switchable wettability patterns,” Journal of physics: condensed matter, Vol. 17, No. 9, pp. S559–S576, 2005.CrossRefGoogle Scholar
  25. 25.
    Berge, B. and Peseux, J., “Variable focal lens controlled by an external voltage: An application of electrowetting,” The European Physical Journal E, Vol. 3, No. 2, pp. 159–163, 2000.CrossRefGoogle Scholar
  26. 26.
    Krupenkin, T., Yang, S. and Mach, P., “Tunable liquid microlens,” Applied Physics Letters, Vol. 82, No. 3, pp. 316–318, 2003.CrossRefGoogle Scholar
  27. 27.
    Kuiper, S. and Hendriks, B. H. W., “Variable-focus liquid lens for miniature cameras,” Applied Physics Letters, Vol. 85, No. 7, pp. 1128–1130, 2004.CrossRefGoogle Scholar
  28. 28.
    Hou, L., Zhang, J., Smith, N., Yang, J. and Heikenfeld, J., “A full description of a scalable microfabrication process for arrayed electrowetting microprisms,” Journal of Micromechanics and Microengineering, Vol. 20, No. 1, Paper No. 015044, 2010.Google Scholar
  29. 29.
    Smith, N. R., Abeysinghe, D. C., Haus, J. W. and Heikenfeld, J., “Agile wide-angle beam steering with electrowetting microprisms,” Optics Express, Vol. 14, No. 14, pp. 6557–6563, 2006.CrossRefGoogle Scholar
  30. 30.
    Beni, G. and Tenan, M. A., “Dynamics of electrowetting displays,” Journal of applied physics, Vol. 52, No. 10, pp. 6011–6015, 1981.CrossRefGoogle Scholar
  31. 31.
    Hayes, R. A. and Feenstra, B. J., “Video-speed electronic paper based on electrowetting,” Nature, Vol. 425, No. 6956, pp. 383–385, 2003.CrossRefGoogle Scholar
  32. 32.
    Roques-carmes, T., Hayes, R. A., Feenstra, B. J. and Schlangen, L. J. M., “Liquid behavior inside a reflective display pixel based on electrowetting,” Journal of applied physics, Vol. 95, No. 8, pp. 4389–4396, 2004.CrossRefGoogle Scholar
  33. 33.
    Acharya, B. R., Krupenkin, T., Ramachandran, S., Wang, Z., Huang, C. C. and Rogers, J. A., “Tunable optical fiber devices based on broadband long period gratings and pumped microfluidics,” Applied Physics Letters, Vol. 83, No. 24, pp. 4912–4914, 2003.CrossRefGoogle Scholar
  34. 34.
    Cheng, J.-Y. and Hsiung, L.-C., “Electrowetting (EW)-Based Valve Combined with Hydrophilic Teflon Microfluidic Guidance in Controlling Continuous Fluid Flow,” Biomedical Microdevices, Vol. 6, No. 4, pp. 341–347, 2004.CrossRefGoogle Scholar
  35. 35.
    Chioua, P. Y., Moonb, H., Toshiyoshic, H., Kimb, C. J. and Wua, M. C., “Light actuation of liquid by optoelectrowetting,” Sensors and actuators A: physical, Vol. 104, No. 3, pp. 222–228, 2003.CrossRefGoogle Scholar
  36. 36.
    Hoshino, K., Triteyaprasert, S., Matsumoto, K. and Shimoyama, I., “Electrowetting-based pico-liter liquid actuation in a glasstube microinjector,” Sensors and actuators A: physical, Vol. 114, No. 2–3, pp. 473–477, 2004.CrossRefGoogle Scholar
  37. 37.
    Shen, N. Y., Liu, Z., Jacquot, B. C., Minch, B. A. and Kan, E. C., “Integration of chemical sensing and electrowetting actuation on chemoreceptive neuron MOS (CvMOS) transistors,” Sensors and actuators B: chemical, Vol. 102, No. 1, pp. 35–43, 2004.CrossRefGoogle Scholar
  38. 38.
    Zhao, Y. J. and Cho, S. K., “Microparticle sampling by electrowetting-actuated droplet sweeping,” Lab on a Chip, Vol. 6, No. 1, pp. 137–144, 2006.CrossRefGoogle Scholar
  39. 39.
    Chung, S. K. and Cho, S. K., “On-chip manipulation of objects using mobile oscillating bubbles,” Journal of Micromechanics and Microengineering, Vol. 18, No. 12, Paper No. 125024, 2008.Google Scholar
  40. 40.
    Srinivasan, V., Pamula, V. K. and Fair, R. B., “Droplet-based microfluidic lab-on-a-chip for glucose detection,” Analytica Chimica Acta, Vol. 507, No. 1, pp. 145–150, 2004.CrossRefGoogle Scholar
  41. 41.
    Lippmann, G., “Relations entre les ph’enom’enes’electriques et capillaires,” Ann. Chim. Phys., Vol. 5, No. 11, pp. 494–549, 1875.Google Scholar
  42. 42.
    Quilliet, C. and Berge, B., “Electrowetting: a recent outbreak,” Current opinion in colloid & Interface science, Vol. 6, No. 1, pp. 34–39, 2001.CrossRefGoogle Scholar
  43. 43.
    Quilliet, C. and Berge, B., “Investigation of effective interface potentials by electrowetting,” Europhysics letters, Vol. 60, No. 1, pp. 99–105, 2002.CrossRefGoogle Scholar
  44. 44.
    Kang, K. H., Kang, I. S. and Lee, C. M., “Electrostatic contribution to line tension in a wedge-shaped contact region,” Langmuir, Vol. 19, No. 22, pp. 9334–9342, 2003.CrossRefMathSciNetGoogle Scholar
  45. 45.
    Jones, T. B., “On the relationship of dielectrophoresis and electrowetting,” Langmuir, Vol. 18, No. 11, pp. 4437–4443, 2002.CrossRefGoogle Scholar
  46. 46.
    Jones, T. B., “An electromechanical interpretation of electrowetting,” Journal of Micromechanics and Microengineering, Vol. 15, No. 6, pp. 1184–1187, 2005.CrossRefGoogle Scholar
  47. 47.
    Zhao, Y. and Cho, S. K., “Micro Air Bubble Manipulation by Electrowetting on Dielectric: transporting, splitting, merging and eliminating of bubbles,” Lab on a Chip, Vol. 7, No. 2, pp. 273–280, 2007.CrossRefMathSciNetGoogle Scholar
  48. 48.
    Berry, S., Kedzierski, J. and Abedian, B., “Irreversible Electrowetting on Thin Fluoropolymer Films,” Langmuir, Vol. 23, No. 24, pp. 12429–12435, 2007.CrossRefGoogle Scholar
  49. 49.
    Zhao, Y. and Cho, S. K. “Micro bubble manipulation towards single cell handling tool,” Proceedings of IEEE International Conference on Robotics and Biomimetics, pp. 269–273, 2005.Google Scholar
  50. 50.
    Janocha, B., Bauser, H., Oehr, C., Brunner, H. and Gopel, W., “Competitive Electrowetting of Polymer Surface by Water and Decane,” Langmuir, Vol. 16, No. 7, pp. 3349–3354, 2000.CrossRefGoogle Scholar
  51. 51.
    Moon, H., Cho, S. S., Garrell, R. L. and Kim, C. J., “Low voltage electrowetting on dielectric,” Journal of applied physics, Vol. 92, No. 7, pp. 4080–4087, 2002.CrossRefGoogle Scholar
  52. 52.
    Peykov, V., Quinn, A. and Ralston, J., “Electrowetting: a model for contact angle saturation,” Colloid and Polymer Science, Vol. 278, No. 8, pp. 789–793, 2000.CrossRefGoogle Scholar
  53. 53.
    Shapiro, B., Moon, H., Garrell, R. L. and Kim, C.-J., “Equilibrium behavior of sessile drops under surface tension, applied external fields, and material variations,” Journal of Applied Physics, Vol. 93, No. 9, pp. 5794–5811, 2003.CrossRefGoogle Scholar
  54. 54.
    Vallet, M., Vallade, M. and Berge, B., “Limiting phenomena for the spreading of water on polymer films by electrowetting by electrowetting,” European Physical Journal, Vol. 11, No. 4, pp. 583–591, 1999.Google Scholar
  55. 55.
    Verheijen, H. J. J. and Prins, M. W. J., “Reversible electrowetting and trapping of charge: model and experiments,” Langmuir, Vol. 15, No. 20, pp. 6616–6620, 1999.CrossRefGoogle Scholar
  56. 56.
    Pollack, M. G., Fair, R. B. and Shenderov, A. D., “Electrowetting-based actuation of liquid droplets for microfluidic applications,” Applied Physics Letters, Vol. 77, No. 11, pp. 1725–1726, 2000.CrossRefGoogle Scholar
  57. 57.
    Pollack, M. G., Shenderov, A. D. and Fair, R. B., “Electrowetting-based actuation of droplets for integrated microfluidics,” Lab on a Chip, Vol. 2, No. 2, pp. 96–101, 2002.CrossRefGoogle Scholar
  58. 58.
    Ren, H., Fair, R. B., Pollack, M. G. and Shaughnessy, E. J., “Dynamics of electro-wetting droplet transport,” Sensors and actuators B: chemical, Vol. 87, No. 1, pp. 201–206, 2002.CrossRefGoogle Scholar
  59. 59.
    Daniel, S. and Chaudhury, M. K., “Rectified motion of liquid drops on gradient surfaces induced by vibration,” Langmuir, Vol. 18, No. 9, pp. 3404–3407, 2002.CrossRefGoogle Scholar
  60. 60.
    Extrand, C. W., “A thermodynamic model for contact angle hysteresis,” Journal of Colloid and Interface Science, Vol. 207, No. 1, pp. 11–19, 1998.CrossRefGoogle Scholar
  61. 61.
    Dickerson, R. E., Gray, H. B. and Haight, G. P., “Chemical Principles,” W. A. Benjamin, Inc., 1974.Google Scholar
  62. 62.
    Furmidge, C. G. L., “Studies at phase interfaces I. The sliding of liquid drops on solid surfaces and a theory for spray retention,” Journal of Colloid Science, Vol. 17, No. 4, pp. 309–324, 1962.CrossRefGoogle Scholar
  63. 63.
    Latorre, L., Kim, J., Lee, J., de Guzman, P.-P., Lee, H. J., Nouet, P. and Kim, C.-J., “Electrostatic actuation of microscale liquidmetal droplets,” Journal of Microelectromechanical Systems, Vol. 11, No. 4, pp. 302–308, 2002.CrossRefGoogle Scholar
  64. 64.
    Smithwick, R. W. III, “Contact-angle studies of microscopic mercury droplets on glass,” Journal of Colloid and Interface Science, Vol. 123, No. 2, pp. 482–485, 1988.CrossRefGoogle Scholar
  65. 65.
    Chung, S. K., Zhao, Y. and Cho, S. K., “On-chip creation and elimination of microbubbles for micro-object manipulator,” Journal of Micromechanics and Microengineering, Vol. 18, No. 9, Paper No. 095009, 2008.Google Scholar
  66. 66.
    Neagu, C., Gardeniers, J. G. E., Elwenspoek, M. and Kelly, J. J., “An electrochemical microactuator: principle and first results,” Journal of Microelectromechanical Systems, Vol. 5, No. 1, pp. 2–9, 1996.CrossRefGoogle Scholar
  67. 67.
    Leighton, T. G., “The Acoustic Bubble,” Academic Press, 1997.Google Scholar
  68. 68.
    Tho, P., Manasseh, R. and Ooi, A., “Cavitation microstreaming patterns in single and multiple bubble systems,” Journal of Fluid Mechanics, Vol. 576, pp. 191–233, 2007.MATHCrossRefGoogle Scholar
  69. 69.
    Marmottant, P. and Hilgenfeldt, S., “Controlled vesicle deformation and lysis by single oscillating bubbles,” Nature, Vol. 423, No. 6936, pp. 153–156, 2003.CrossRefGoogle Scholar
  70. 70.
    Marmottant, P., Raven, J. P., Gardeniers, H., Bomer, J. G. and Hilgenfeldt, S., “Microfluidics with ultrasound-driven bubbles,” Journal of Fluid Mechanics, Vol. 568, pp. 109–118, 2006.MATHCrossRefGoogle Scholar
  71. 71.
    Ko, S. H., Lee, S. J. and Kang, K. H., “A synthetic jet produced by electrowetting-driven bubble oscillations in aqueous solution,” Applied Physics Letters, Vol. 94, No. 19, Paper No. 194102, 2009.Google Scholar
  72. 72.
    Coakley, W. T. and Nyborg, W., “Cavitation; dynamics of gas bubbles; applications,” Elsevier: New York, pp. 77–159, 1978.Google Scholar
  73. 73.
    Miller, D. L., “Particle gathering and microstreaming near ultrasonically activated gas-filled micropores,” Journal of Acoustical Society of America, Vol. 84, No. 4, pp. 1378–1387, 1988.CrossRefGoogle Scholar
  74. 74.
    Chung, S. K. and Cho, S. K., “3-D manipulation of millimeterand micro-sized objects using an acoustically-excited oscillating bubble,” Microfluidics and Nanofluidics, Vol. 6, No. 2, pp. 261–265, 2008.CrossRefGoogle Scholar
  75. 75.
    Chung, S. K. and Cho, S. K., “Capturing, carrying, and releasing of micro-objects by AC-electrowetting-actuated oscillating bubbles,” The 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers 2009), pp. 821–824, 2009.Google Scholar
  76. 76.
    Chung, S. K., Zhao, Y., Yi, U.-C. and Cho, S. K., “Micro bubble fluidics by EWOD and ultrasonic excitation for micro bubble tweezers,” 20th International Conference on Micro Electro Mechanical Systems (MEMS), pp. 31–34, 2007.Google Scholar
  77. 77.
    Papavasiliou, A. P., “Bubble-actuated planar microvalves,” Ph. D. Thesis, Department of Mechanical Engineering, University of California, Berkeley, pp. 1–118, 2001.Google Scholar
  78. 78.
    Suzuki, H. and Yoneyama, R., “A reversible electrochemical nanosyringe pump and some considerations to realize low-power consumption,” Sensors and Actuators B: chemical, Vol. 86, No. 2–3, pp. 242–250, 2002.CrossRefGoogle Scholar
  79. 79.
    Yang, S.-C. and Liu, C.-H., “An electrolysis-bubble-actuated micropump using electrowetting on dielectric (EWOD) for 1xN micro-sample switches,” The 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers 2009), pp. 2018–2021, 2009.Google Scholar
  80. 80.
    Liu, R. H., Yang, J., Pindera, M. Z., Athavale, M. and Grodzinski, P., “Bubble-induced acoustic micromixing,” Lab on a Chip, Vol. 2, No. 3, pp. 151–157, 2002.CrossRefGoogle Scholar
  81. 81.
    Chung, S. K. and Cho, S. K., “Oscillating Mobile Bubbles for Microfluidic Mixing Enhancement,” The 11th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS 2007), pp. 913–915, 2007.Google Scholar
  82. 82.
    Ryu, K., Chung, S. K. and Cho, S. K., “Separation and Collection of Microparticles Using Oscillating Bubbles,” The 12th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS 2008), pp. 1471–1473, 2008.Google Scholar
  83. 83.
    Chung, S. K., Ryu, K. and Cho, S. K., “Electrowetting propulsion of water-floating objects,” Applied Physics Letters, Vol. 95, No. 1, Paper No. 014107, 2009.Google Scholar
  84. 84.
    Gao, X. and Jiang, L., “Biophysics: Water-repellent legs of water striders,” Nature, Vol. 432, No. 7013, pp. 36–38, 2004.CrossRefGoogle Scholar
  85. 85.
    Hu, D. L. and Bush, J. W. M., “Meniscus-climbing insects,” Nature, Vol. 437, No. 7059, pp. 733–736, 2005.CrossRefGoogle Scholar
  86. 86.
    Hu, D. L., Chan, B. and Bush, J. W. M., “The hydrodynamics of water strider locomotion,” Nature, Vol. 424, No. 6949, pp. 663–666, 2003.CrossRefGoogle Scholar
  87. 87.
    Lee, S. M., Oh, D. J., Jung, I. D., Bae, K. M., Jung, P. G., Chung, K. H., Cho, S.-J. and Ko, J. S., “Fabrication of Nickel Micromesh Sheets and Evaluation of their Water-repellent and Waterproof Abilities,” Int. J. Precis. Eng. Manuf., Vol. 10, No. 3, pp. 161–166, 2009.CrossRefGoogle Scholar
  88. 88.
    Song, Y. S. and Sitti, M., “Surface-Tension-Driven Biologically Inspired Water Strider Robots: Theory and Experiments,” IEEE Transactions on robotics, Vol. 23, No. 3, pp. 578–589, 2007.CrossRefGoogle Scholar
  89. 89.
    Mita, Y., Li, Y., Kubota, M., Parkes, W., Haworth, L. I., Flynn, B. W., Terry, J. G., Tang, T.-B., Ruthven, A. D., Smith, S. and Walton, A. J., “Demonstration of a wireless driven MEMS pond skater that uses EWOD technology,” Solid-State Electronics, Vol. 53, No. 7, pp. 798–802, 2009.CrossRefGoogle Scholar
  90. 90.
    Donald, B. R., Levey, C. G., McGray, C. D., Paprotny, I. and Rus, D., “An Untethered, Electrostatic, Globally Controllable MEMS Micro-Robot,” Journal of Microelectromechanical Systems, Vol. 15, No. 1, pp. 1–15, 2006.CrossRefGoogle Scholar
  91. 91.
    Jager, E. W. H., Inganäs, O. and Lundström, I., “Microrobots for Micrometer-Size Objects in Aqueous Media: Potential Tools for Single-Cell Manipulation,” Science, Vol. 288, No. 5475, pp. 2335–2338, 2000.CrossRefGoogle Scholar
  92. 92.
    Watson, B., Friend, J. and Yeo, L., “Piezoelectric ultrasonic resonant motor with stator diameter less than 250 μm: the Proteus motor,” Journal of Micromechanics and Microengineering, Vol. 19, No. 2, Paper No. 022001, 2009.Google Scholar
  93. 93.
    Yesin, K. B., Vollmers, K. and Nelson, B. J., “Modeling and Control of Untethered Biomicrorobots in a Fluidic Environment Using Electromagnetic Fields,” The International Journal of Robotics Research, Vol. 25, No. 5–6, pp. 527–536, 2006.CrossRefGoogle Scholar
  94. 94.
    Zhang, L., Abbott, J. J., Dong, L., Kratochvil, B. E., Bell, D. and Nelson, B. J., “Artificial bacterial flagella: Fabrication and magnetic control,” Applied Physics Letters, Vol. 94, No. 6, Paper No. 064107, 2009.Google Scholar
  95. 95.
    Cho, K.-J., Koh, J.-S., Kim, S., Chu, W.-S., Hong, Y. and Ahn, S.-H., “Review of Manufacturing Processes for Soft Biomimetic Robots,” Int. J. Precis. Eng. Manuf., Vol. 10, No. 3, pp. 171–181, 2009.CrossRefGoogle Scholar
  96. 96.
    Chung, S. K. and Cho, S. K., “Propulsion by Acoustically Excited Oscillating Bubbles for Biomedical Micro/Mini Robots Swimming Inside Human Body,” The 13th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS 2009), pp. 1485–1487, 2009.Google Scholar
  97. 97.
    Ryu, K., Zueger, J., Chung, S. K. and Cho, S. K., “Underwater Propulsion Using AC-Electrowetting-Actuated Oscillating Bubbles for Swimming Robots,” The 23st International Conference on Micro Electro Mechanical Systems (MEMS 2010), pp. 160–163, 2010.Google Scholar

Copyright information

© Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringMyongji UniversityGyeonggidoSouth Korea
  2. 2.Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPittsburghUSA

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