Koya Narumi / 鳴海紘也

Koya Narumi (鳴海紘也,なるみこうや) is a Ph.D student and a researcher in the department of Information and Communication Engineering, The University of Tokyo. His research interests are in the areas of Digital Fabrication and High-low Tech, where he has especially been working on Paper Electronics and Shape Changing Interface. His research goal is to allow not only experts but also non-experts to have diverse design choices in digital fabrication, in the electric, mechanical, optical, and electromagnetic manner. He is currently advised by Yoshihiro Kawahara and working as a project researcher of ERATO Kawahara Universal Information Network Project.

He received his M.E. in 2017 and B.E. in 2015 respectively. He is a student member of ACM, IEEE, IEICE, and RSJ. 


Research Projects (Selected)

Circuit Eraser (1st author, CHI'15 WiP)

Circuit Eraser enables us to erase/rewrite conductive ink traces on paper, again and again, resulting in the iterative design of hand-drawn/printed conductive ink circuit using the off-the-shelf and safe material. This project aims at solving the problem of novices, tinkers, and artists not having the tools for trial-and-error in their conductive ink circuit. This technique was commercialized by AgIC Inc. and is now affordable for everyone.

ConductAR (1st author, UbiComp'15, Honorable Mention Award)

ConductAR is an augmented reality-based tool which tells users parameters of conductive ink circuit (like sheet resistance) and better options for drawing the circuit with accessible tablet or PC. It recognizes the circuit image and calculates parameters using finite element method (FEM). It also adopts sparse coding for acceleration of inverse matrix problem. ConductAR gives users the knowledge to fix their conductive ink circuit on the spot, without troublesome CAD design process. Combining this with Circuit Eraser, users can try their first design, learn what leads to errors, and erase/redraw their circuit until finishing their artwork.

Electric Phase-change Actuator (2nd author, ICRA'17)


One of the main challenges for soft-robotics is the acceleration of prototyping processes from idea to implementation. Integrated fabrication of body structures, actuators, sensors, and antennas can be a better way to solve this challenge.
We took advantage of the liquid-to-gas phase change and proposed an electric phase-change actuator comprising a printable fluidic actuator controlled by an inkjet-printed electric heater. This actuator can easily be integrated not only with origami robots, but also electric wires and sensors implemented with conductive ink. We theoretically analyzed the dynamics of electro-fluidic conversion in the actuator and compared it with actual measurement data. We verified the proposed actuator in real examples of a shape-shifting origami structure and a robot gripper with a printed touch sensor.

Papilion (3rd author, Ars Electronica'17)

Papilion is an environmentally responsive experimental architecture making use of soft robotics technology. The surface covering the dome can change shape by the wing-like units using actuators driven by temperature conditions. It seems that the building itself is breathing. This is a proposal for an architectural element, that differs from the usual hard ones.

The viewer can experience this surface adapting to the environment, inviting in light, moisture and sound. The wing-like units of the surface are modular and can thus be replaced or expanded. It is also possible even to mass-produce cheap individual units using printing technology.

Other Projects related to Computational Fabrication

Phones on Wheels (joint 1st authors, UIST'16 Demo)

"Phones on Wheels" project comes from an assignment in Koji Yatani's class in grad school. it introduces interaction and applications using smartphones with kinetic capabilities. We develop an accessory module with robot wheels for a smartphone. With this module, the smartphone can move in a linear direction or rotate with sufficient power. The module also includes rotary encoders, allowing us to use the wheels as an input modality. We demonstrate a series of novel mobile interaction for mobile devices with kinetic capabilities through three applications.

  • Honorable Mention Award, in Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp), ACM, 2015.


  • IEEE Pervasive Computing (2017)
  • IEEE IROS (2017)


  • JSPS Research Fellowship for Young Scientists (日本学術振興会特別研究員DC1) (Apr. 2017 -)


Domestic Journal

  1. 鳴海紘也, 中原健一, 川原圭博, "ConductAR: 導電性インク回路の試行錯誤的なデザインに向けたARツール, " 情報処理学会論文誌, To appear in Oct. 2017.

International Conference

  1. Narumi, K., Hodges, S. & Kawahara, Y., "ConductAR: An Augmented Reality Based Tool for Iterative Design of Conductive Ink Circuits," in Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp), 791–800 (ACM, 2015).
  2. Ta, T., Fukumoto, M., Narumi, K., Shino, S., Kawahara, Y. & Asami, T., "Interconnection and Double Layer for Flexible Electronic Circuit with Instant Inkjet Circuits," in Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp), 181–190 (ACM, 2015).
  3. Hashizume, T., Sasatani, T., Narumi, K., Narusue, Y., Kawahara, Y. & Asami, T., "Passive and Contactless Epidermal Pressure Sensor Printed with Silver Nano-particle Ink," in Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp), 190–195 (ACM, 2016).
  4. Nakahara, K., Narumi, K., Niiyama, R. & Kawahara. Y., "Electric Phase-change Actuator with Inkjet Printed Flexible Circuit for Printable and Integrated Robot Prototyping," in 2012 IEEE International Conference on Robotics and Automation (ICRA), (IEEE, to appear in May, 2017).

International Demo and Poster

  1. Narumi, K., Shi, X., Hodges, S., Kawahara, Y., Shimizu, S. & Asami, T., "Circuit Eraser: A Tool for Iterative Design with Conductive Ink," in Proceedings of the 33rd Annual ACM Conference Extended Abstracts on Human Factors in Computing Systems (CHI), 2307–2312 (ACM, 2015).
  2. Narumi, K.*, Hiraki, T.*, Yatani, K. & Kawahara, Y., "Phones on Wheels: Exploring Interaction for Smartphones with Kinetic Capabilities," in Proceedings of the 29th Annual Symposium on User Interface Software and Technology (UIST), 121–122 (ACM, 2016, *: joint first authors).

Art Exhibition

  1. Sato, H., Nakahara. K., Narumi, K., Kakehi. Y., Niiyama. R., & Kawahara, Y., "Papilion," in Ars Electronica (2017).

Domestic Conference and Poster (in Japanese)

  1. 鳴海紘也, 杉本雅明, 清水信哉, 川原圭博, 浅見徹, ”銀ナノインクでの回路プロトタイピングにおける書き直し特性の計測,” 電子情報通信学会ソサイエティ大会公演論文集, B-18-3, Sept. 2014.
  2. 奥谷文徳, 鳴海紘也, 川原圭博, 浅見徹, ”圧縮センシングを用いた心拍の計測手法における復元精度の評価,” 電子情報通信学会ソサイエティ大会公演論文集, B-18-10, Sept. 2014.
  3. 鳴海紘也, 川原圭博, 浅見徹, ”手書き回路の解析が可能な CAD ソフトの実装に向けた導電性インクのシート抵抗の画像認識手法,” 電子情報通信学会総合大会公演論文集, Bー15ー16, Mar. 2015.
  4. 鳴海紘也, “銀ナノインクによるアドホックな回路作成のための支援ツール,”紙のエレクトロニクス応用研究会,第5回技術研究発表会, Nov. 2015.
  5. 鳴海紘也. 小野寺宏,  “In vivoでのマウス頭蓋骨透明化に向けた骨片透明化試験,” 第77回応用物理学会秋季学術講演会, Sept. 2016.
  6. 中原健一. 鳴海紘也, 川原圭博,浅見徹,”銀ナノインク回路の過電流からの防護に向けた発熱量分布の可視化,” 電子情報通信学会ソサイエティ大会公演論文集, B-18-5, Sept. 2016.
  7. 中原健一, 鳴海紘也, 川原圭博, 浅見徹, ”電気回路と一体で印刷可能なアクチュエータによる動的インターフェイス及びロボットの試作,” 情報処理学会第79回全国大会, Mar. 2017.
  8. 鳴海紘也,岸野文昭,根東覚,大木研一,小野寺宏,"哺乳類脳神経活動のin vivo観察に向けた透明化試薬によるin vitro及びin vivoでのマウス頭蓋骨透明化," 第17回 東京大学生命科学シンポジウム,Apr. 2017.