Programmable Liquid Matter: 2D Shape Deformation of Highly Conductive Liquid Metals in a Dynamic Electric Field

ABSTRACT

In this paper, we demonstrate a method for the dynamic 2D transformation of liquid matter and present unique organic animations based on spatio-temporally controlled electric fields. In particular, we deploy a droplet of liquid metal (Gallium indium eutectic alloy) in a 7x7 electrode array prototype system, featuring an integrated image tracking system and a simple GUI. Exploiting the strong dependance of EGaIn's surface tension on external electric voltages, we control multiple electrodes dynamically to manipulate the liquid metal into a fine-grained desired shape. Taking advantage of the high conductivity of liquid metals, we introduce a shape changing, reconfigurable smart circuit as an example of unique applications. We discuss system constraints and the overarching challenge of controlling liquid metals in the presence of phenomena such as splitting, self-electrode interference and finger instabilities. Finally, we reflect on the broader vision of this project and discuss our work in the context of the wider scope of programmable materials.

References

1. Chakraborty, S. Electrocapillary. Springer US, Boston, MA, 2013, 1--15.
2. Coelho, M., and Zigelbaum, J. Shape-changing interfaces. Personal and Ubiquitous Computing 15, 2 (Feb 2011), 161--173.
3. Deng, Y.-G., and Liu, J. Corrosion development between liquid gallium and four typical metal substrates used in chip cooling device. Applied Physics A 95, 3 (Jun 2009), 907--915.
4. Dickey, M. D., Chiechi, R. C., Larsen, R. J., Weiss, E. A., Weitz, D. A., and Whitesides, G. M. Eutectic gallium-indium (egain): A liquid metal alloy for the formation of stable structures in microchannels at room temperature. Advanced Functional Materials 18, 7 (2008), 1097--1104.
5. Döring, T., Sylvester, A., and Schmidt, A. Ephemeral user interfaces: Valuing the aesthetics of interface components that do not last. interactions 20, 4 (July 2013), 32--37.
6. Follmer, S., Leithinger, D., Olwal, A., Hogge, A., and Ishii, H. inform: Dynamic physical affordances and constraints through shape and object actuation. In Proceedings of the 26th Annual ACM Symposium on User Interface Software and Technology, UIST '13, ACM (New York, NY, USA, 2013), 417--426.
7. G. Beni, S. Hackwood, J. J. Continuous electrowetting effect. Appl. Phys. Lett 40 (1982).
8. Goldstein, S. C., Campbell, J. D., and Mowry, T. C. Programmable matter. IEEE Computer 38, 6 (June 2005), 99--101.
9. Harrison, C., and Hudson, S. E. Providing dynamically changeable physical buttons on a visual display. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, CHI '09, ACM (New York, NY, USA, 2009), 299--308.
10. Hawkes, E., An, B., Benbernou, N. M., Tanaka, H., Kim, S., Demaine, E. D., Rus, D., and Wood, R. J. Programmable matter by folding. Proceedings of the National Academy of Sciences 107, 28 (2010), 12441--12445.
11. Health and Safety Executive. ALARP "at a glance". accessed 08/2017.
12. Hirayama, S., and Kakehi, Y. Shaboned display: An interactive substantial display using soap bubbles. In ACM SIGGRAPH 2010 Emerging Technologies, SIGGRAPH '10, ACM (New York, NY, USA, 2010), 21:1--21:1.
13. Hu, L., Wang, L., Ding, Y., Zhan, S., and Liu, J. Manipulation of liquid metals on a graphite surface. Advanced Materials 28, 41 (2016), 9210--9217.
14. IEEE GlobalSpec. Electrodes and electrode materials information. Accessed: 2017-08-28.
15. Ishii, H., Lakatos, D., Bonanni, L., and Labrune, J.-B. Radical atoms: Beyond tangible bits, toward transformable materials. interactions 19, 1 (Jan. 2012), 38--51.
16. Jansen, Y. Mudpad: Fluid haptics for multitouch surfaces. In CHI '10 Extended Abstracts on Human Factors in Computing Systems, CHI EA '10, ACM (New York, NY, USA, 2010), 4351--1356.
17. Kojima, Y., Fujimoto, T., Itoh, Y., and Nakajima, K. Polka dot: The garden of water spirits. In SIGGRAPH Asia 2013 Emerging Technologies, SA '13, ACM (New York, NY, USA, 2013), 15:1--15:2.
18. L.D. Landau, E. L. Electrodynamics of Continuous Media. Pergamon, 1986.
19. Lee, J., Post, R., and Ishii, H. Zeron: Mid-air tangible interaction enabled by computer controlled magnetic levitation. In Proceedings of the 24th Annual ACM Symposium on User Interface Software and Technology, UIST '11, ACM (New York, NY, USA, 2011), 327--336.
20. Lippmann, M. G. Relations entre les phnomnes electriques et capillaires. Ann. Chim. Phys. 5 (1875).
21. Lu, Q., Mao, C., Wang, L., and Mi, H. Lime: Liquid metal interfaces for non-rigid interaction. In Proceedings of the 29th Annual Symposium on User Interface Software and Technology, UIST '16, ACM (New York, NY, USA, 2016), 449--152.
22. Lum, G. Z., Ye, Z., Dong, X., Marvi, H., Erin, O., Hu, W., and Sitti, M. Shape-programmable magnetic soft matter. Proceedings of the National Academy of Sciences 113, 41 (2016), E6007--E6015.
23. Masson, N., and Mackay, W. E. WeMe: Seamless Active and Passive Liquid Communication. Springer Berlin Heidelberg, Berlin, Heidelberg, 2009, 694--700.
24. Miruchna, V., Walter, R., Lindlbauer, D., Lehmann, M., von Klitzing, R., and Müller, J. Geltouch: Localized tactile feedback through thin, programmable gel. In Proceedings of the 28th Annual ACM Symposium on User Interface Software & Technology, UIST '15, ACM (New York, NY, USA, 2015), 3--10.
25. Morales, D., Stoute, N. A., Yu, Z., Aspnes, D. E., and Dickey, M. D. Liquid gallium and the eutectic gallium indium (egain) alloy: Dielectric functions from 1.24 to 3.1 ev by electrochemical reduction of surface oxides. Applied Physics Letters 109, 9 (2016), 091905.
26. Niiyama, R., Yao, L., and Ishii, H. Weight and volume changing device with liquid metal transfer. In Proceedings of the 8th International Conference on Tangible, Embedded and Embodied Interaction, TEI '14, ACM (New York, NY, USA, 2013), 49--52.
27. Ogata, M., and Fukumoto, M. Fluxpaper: Reinventing paper with dynamic actuation powered by magnetic flux. In Proceedings of the 33rd Annual ACM Conference on Human Factors in Computing Systems, CHI '15, ACM (New York, NY, USA, 2015), 29--38.
28. Paolo Di Marco, Walter Grassi, G. M. T. T. A. T. S. H. Influence of electric field on single gas-bubble growth and detachment in microgravity. International Journal of Multiphase Flow 29 (2003).
29. Parekh, D. P., Ladd, C., Panich, L., Moussa, K., and Dickey, M. D. 3d printing of liquid metals as fugitive inks for fabrication of 3d microfluidic channels. Lab Chip 16 (2016), 1812--1820.
30. Parkes, A., and Dickie, C. A biological imperative for interaction design. In CHI '13 Extended Abstracts on Human Factors in Computing Systems, CHI EA '13, ACM (New York, NY, USA, 2013), 2209--2218.
31. Parkes, A., and Offenhuber, D. Dewy: A condensation display. In ACM SIGGRAPH 2007 Posters, SIGGRAPH '07, ACM (New York, NY, USA, 2007).
32. Robinson, S., Coutrix, C., Pearson, J., Rosso, J., Torquato, M. F., Nigay, L., and Jones, M. Emergeables: Deformable displays for continuous eyes-free mobile interaction. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems, CHI '16, ACM (New York, NY, USA, 2016), 3793--3805.
33. Roudaut, A., Karnik, A., Löchtefeld, M., and Subramanian, S. Morphees: Toward high "shape resolution" in self-actuated flexible mobile devices. In Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, CHI '13, ACM (New York, NY, USA, 2013), 593--602.
34. Sahoo, D. R., Hornbæk, K., and Subramanian, S. Tablehop: An actuated fabric display using transparent electrodes. In Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems, CHI '16, ACM (New York, NY, USA, 2016), 3767--3780.
35. Sahoo, D. R., Nakamura, T., Marzo, A., Omirou, T., Asakawa, M., and Subramanian, S. Joled: A mid-air display based on electrostatic rotation of levitated janus objects. In Proceedings of the 29th Annual Symposium on User Interface Software and Technology, UIST '16, ACM (New York, NY, USA, 2016), 437--448.
36. Sigma-Aldrich. Galliumindium eutectic. Accessed 08/2017.
37. Sutherland, I. E. The ultimate display. In Proceedings of the IFIP Congress (1965), 506--508.
38. TIB-TECH. As a basis for comparison, the conductivity of copper is ~ 58.5 x 106 S/m and Lead is ~ 4.7 x 106 S/m. Accessed 08/2017.
39. Tsai, J. T. H., Ho, C.-M., Wang, F.-C., and Liang, C.-T. Ultrahigh contrast light valve driven by electrocapillarity of liquid gallium. Applied Physics Letters 95, 25 (2009), 251110.
40. Tsujimoto, Y., Itoh, Y., and Onoye, T. Ketsuro-graffiti: An interactive display with water condensation. In Proceedings of the 2016 ACM on Interactive Surfaces and Spaces, ISS '16, ACM (New York, NY, USA, 2016), 49--55.
41. V. Mohan, K. Padmanabham, K. C. Marangoni effects under electric fields. Adv. Space Research 3 (1983), 177--180.
42. Wakita, A., and Nakano, A. Blob manipulation. In Proceedings of the Sixth International Conference on Tangible, Embedded and Embodied Interaction, TEI '12, ACM (New York, NY, USA, 2012), 299--302.
43. Wakita, A., Nakano, A., and Kobayashi, N. Programmable blobs: A rheologic interface for organic shape design. In Proceedings of the Fifth International Conference on Tangible, Embedded, and Embodied Interaction, TEI '11, ACM (New York, NY, USA, 2011), 273--276.
44. Wang, L., and Liu, J. Graphite induced periodical self-actuation of liquid metal. RSC Adv. 6, 65 (2016), 60729--60735.
45. Wang, X., and Liu, J. Recent advancements in liquid metal flexible printed electronics: Properties, technologies, and applications. Micromachines 7, 12 (2016).
46. Yao, Y.-y., and Liu, J. A polarized liquid metal worm squeezing across a localized irregular gap. RSC Adv. 7 (2017), 11049--11056.
47. Zhang, J., Guo, R., and Liu, J. Self-propelled liquid metal motors steered by a magnetic or electrical field for drug delivery. J. Mater. Chem. B 4 (2016), 5349--5357.
48. Zhang, J., Sheng, L., and Liu, J. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects. Scientific reports 4 (2014), 7116.

Index Terms

• Human-centered computing