One of our basic approaches for R&D is to “observe, understand, and emulate” living creatures with flight capabilities; we observe the flight characteristics of insects and birds and analyze them using engineering tools. The second approach is to create clever drones through improving the control system and design of drones. With these approaches, we aim to overcome the challenges of existing drones and develop novel drones.

 

Unmanned Aerial Robot with Flapping Wings

Insects and birds can fly stably with their small bodies. We observe the features of i hawkmoths and hummingbirds, reveal the aerodynamic mechanism of their flight, and apply it to the wings of aerial robots. The latest model, second-generation, weighs between 3.0 and 7.0g. This small, maneuvering robot is expected to be used for reconnaissance in buildings during emergencies such as disasters, and disinfection to prevent spreading infectious diseases.
DOI:10.1088/1748-3182/6/4/045002

 

 

Owl-inspired Silent Rotor for Drone

Owls are known for their silent flight. We observe the features of owls' feathers, analyze the mechanism behind the silence, and apply it to the rotor of drones. We have tested a variety of attachments to rotors and successfully reduced the noise generated from rotors on a hovering drone. We are now developing quieter and more stable rotor-blades, taking inspiration from the other kinds of birds.
DOI:10.20965/jrm.2018.p0337

 

 

Psychoacoustic Analysis

It is well known that the location of a drone's propellers creates much noise. The noise level of a flying drone reaches way more than a running car. At CAIV, we are developing silent rotor blades, but it is also essential to investigate how the human ear hears these sounds. In our anechoic chamber, we analyze the psychoacoustic effects of each noise by recording the sound with a microphone array while adjusting the rotation speed in various types of propellers.

 

Optimization of Propeller Configuration

Typical drones have four propellers. We are studying to find the best formation for propeller inclination and distance between propellers from aerodynamic performance. CAIV's equipment can perform various experiments on propeller formation with automatic rotation control and data acquisition. In addition, we use Computational Fluid Dynamics (CFD) simulations to understand aerodynamic performance and the physics of the flow.

 

Bird-inspired Rotor with Collision-Safety Function

Birds’ flight is surprisingly robust even at low altitude or in turbulent air. We are now developing rotors inspired by bird's wings. We have just completed a prototype of the rotor that can reduce the impact of collisions. We are also developing rotors that are resistant to unpredictable turbulent air.

 

Small Drones with Coordinated Flight System

Small drones less than 200g are known to easy to use in terms of law regulations. We are developing a system to realize coordinated flights between multiple small drones. The system can be used for inspecting plumbings in a city or collecting information inside buildings during a disaster.

 

 

Fast visual servos to control drone flight

One of the challenges for exisitng drones is to respond quickly to visual information. “High-speed vision” is one way to tackle this challenge. Using a high-speed monocular camera and a parallel processing unit for image processing, we are working on visual feedback control with a rate of 30 Hz to realize a stable flight control.

 

FY 2022

Liu, Nakata lab, Yonezawa

J. Wang, K. Ishibashi, T. Ikeda, T. Fujii, T. Nakata, H. Liu. 
Morphological effects of leading-edge serrations on acoustic signatures of a mixed flow fan
Phys. Fluids., 34(4), 041909(2022) .
DOI:10.1063/5.0088851

Y. Xue, X. Cai, H. Liu. 
Effects of Wing-body Interaction on Hawkmoth Aerodynamics and Energetics at Various Flight Velocities
Phys. Fluids., 34, 051915(2022).
DOI:10.1063/5.0087161

A. Jr Asignacion, S. Suzuki, R. Noda, T. Nakata, H. Liu. 
Frequency-based Wind Gust Estimation for Quadrotors using a Nonlinear Disturbance Observe
IEEE Robotics and Automation Letters (RA-L), (2022).
https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9827490

Y. Xue, X. Cai, D. Kolomenskiy, R. Xu, H. Liu. 
Elastic Storage Enables Robustness of Flapping Wing Dynamics
Bioinspir. Biomim., (2022).
10.1088/1748-3190/ac6c66

H. Liu, S. Suzuki, W. Wang, H. Liu, Q. Wang. 
Robust Control Strategy for Quadrotor Drone Using Reference Model-Based Deep Deterministic Policy Gradient
Drones, 1856824(2022).
10.3390/drones6090251

R. Noda, T. Ikeda, T. Nakata, H. Liu. 
Characterization of the low-noise drone propeller with serrated Gurney flap
Frontiers in Aerospace Engineering, 1:1004828(2022) .
10.3389/fpace.2022.1004828

Namiki Lab

並木明夫,
多眼視覚ロボット
日本ロボット学会誌, Vol.40, No.5, pp.387-392,(2022) .
10.7210/jrsj.40.387

FY 2021

Liu, Nakata lab, Yonezawa

S. E. Farisenkov, D. Kolomenskiy, N. A. Lapina, P. N. Petrov, T. Engels, F-O Lehmann, R. Onishi, H. Liu, A. A. Polilov. 
Novel flight style and light wings boost flight performance of tiny beetles 
Nature. 25,103692 (2022).
DOI:10.1038/s41586-021-04303-7

Y. Jiang, P. Zhao, X. Cai, J. Rong, Z. Dong, H. Chen, P. Wu, H. Hu, X. 
Bristled-wing design of materials, microstructures and aerodynamics enables flapping flight in tiny wasps. 
iScience. 25,103692 (2022).
DOI:10.1016/j.isci.2021.103692

J. Rong, H. Liu 
Aeroacoustic interaction between owl-inspired trailing-edge fringes and leading-edge serrations
Physics of Fluids . 34, 011907 (2022).
DOI:10.1063/5.0078974

Y. Li, K. Yonezawa, H. Liu
Effect of Ducted Multi-Propeller Configuration on Aerodynamic Performance in Quadrotor Drone
Drones . 5(3), 101 (2021).
DOI:10.3390/drones5030101

J. Wang, K. Ishibashi, M. Joto, T. Ikeda, T. Fujii, T. Nakata, H. Liu. 
Aeroacoustic characteristics of owl-inspired blade designs in a mixed flow fan: effects of leading- and trailing-edge serrations
Bioinspiration & Biomimetics. 16, 6 (2021).
DOI:10.1088/1748-3190/ac1309

Y. Li, K. Yonezawa, R. Xu, H. Liu. 
A Biomimetic Rotor-configuration Design for Optimal Aerodynamic Performance in Quadrotor Drone
Journal of Bionic Engineering . 18, pages 824–839 (2021).
DOI:10.1007/s42235-021-0069-0

Xuefei Cai, H. Liu. 
A six-degree-of-freedom proportional-derivative control strategy for bumblebee flight stabilization
Journal of Biomechanical Science and Engineering. 16, 4, 21-00113 (2021).
DOI:10.1299/jbse.21-00113

Y. Murayama, T. Nakata, H. Liu.
Flexible Flaps Inspired by Avian Feathers Can Enhance Aerodynamic Robustness in low Reynolds Number Airfoils
Frontiers in Bioengineering and Biotechnology. 9, 612182 (2021).
DOI:10.3389/fbioe.2021.612182

S. Koizumi, T. Nakata, H. Liu.
Flexibility Effects of a Flapping Mechanism Inspired by Insect Musculoskeletal System on Flight Performance 
Frontiers in Bioengineering and Biotechnology. 9, 612183 (2021).
DOI:10.3389/fbioe.2021.6121832

　　　　　 　　　　　

劉浩
昆虫に学ぶバイオミメティクス
昆虫と自然, 12月臨時増刊号, ニュー・サイエンス社，2-4 (2021).

　　　　　

劉浩
次世代ドローンにおけるバイオミメティクス技術研究開発の動向
月刊機能材料, 2022年3月号.

　　

中田敏是
蚊の飛行メカニズム
昆虫と自然, 12月臨時増刊号, ニュー・サイエンス社，20-23 (2021).

Namiki lab

　　　　　

A.Namiki and S. Yokosawa.
Origami Folding by Multifingered Hands with Motion Primitives
Cyborg and Bionic Systems Volume 2021, Article ID 9851834 (2021).
DOI:10.34133/2021/9851834

　　

D. He, H. Chuang, J. Chen, J. Li, and A. Namiki
Real-Time Visual Feedback Control of Multi-Camera UAV
Journal of Robotics and MechatronicsVol.33 No.2, pp. 263-273, (2021).
DOI:10.20965/jrm.2021.p0263

X. Sun, H. Naito, A. Namiki, Y. Liu, T. Matsuzawa and A. Takanishi
Assist system for remote manipulation of electric drills by the robot “WAREC-1R” using deep reinforcement learning
RoboticaVol. 40 , Issue 2, 365-376, (2022).
DOI:10.1017/S0263574721000618

　

Arai lab

　　　　

浪越圭一，荒井幸代
並列座標降下法によるマルチエージェント逆強化学習の学習速度改善
人工知能学会論文誌, Vol. 36, No.5, (2021).
DOI:10.1527/tjsai.36-5_AG21-B

D. Kishikawa and S. Arai
Estimation of personal driving style via deep inverse reinforcement learning
Artif Life Robotics, 26, 338–346 (2021).
DOI:10.1007/s10015-021-00682-2

Y. Yoshida, S. Arai, H. Kobayashi, K. Kondo
Charge/Discharge Control of Wayside Batteries via Reinforcement Learning for Energy-Conservation in Electrified Railway Systems
Electrical Engineering Japan, Vol. 140 No. 11, 807–816, (2021).
DOI:10.1002/eej.23319

Kohri lab

T. Okoshi, T. Iwasaki, S. Takahashi, Y. Iwasaki, K. Kishikawa, and M. Kohri
Control of structural coloration by natural sunlight irradiation on a melanin precursor polymer inspired by skin tanning
Biomacromolecules, 22, 1730-1738, (2021).
DOI:10.1515/nanoph-2021-0437

Y. Kojima, K. Kishikawa, S. Ichikawa, J. Matsui, K. Hirai, Y. Kondo, and M. Kohri
Stimuli-responsive biomimetic metallic luster film using dye absorption and specular reflection from layered microcrystals
ACS Appl.Polym. Mater., 3, 1819-1827, (2021). 
DOI:10.1021/acsapm.0c01396

M. Kohri, A. Kobayashi, T. Okoshi, H. Shirasawa, K. Hirai, K. Ujiie, T. Kojima, and K. Kishikawa
Bright solvent sensor using an inverse opal structure containing melanin-mimicking polydopamine
Chem. Lett., 50, 106-109. (2021). 
DOI:10.1246/cl.200626

H. Kawaguchi, K. Umesato, K. Takahashi, K. Yamane, R. Morita, K. Yuyama, S. Kawano, K. Miyamoto, M. Kohri, and T. Omatsu 
Generation of hexagonal close-packed ring-shaped structures using an optical vortex
Nanophotonics, 000010151520210437, (2021). 
DOI:10.1515/nanoph-2021-0437

桑折道済
玉虫と孔雀の美しさ/人工メラニンによる構造発色材料
Biomimetica, 4, 12-13, (2021). 

Ishikawa lab

石川 裕之
昆虫の翅の発生機構と制御
昆虫と自然, 12月臨時増刊号, ニュー・サイエンス社，5-9 (2021).

Takahashi lab

斉藤 京太・高橋 佑磨
トンボ目の翅の進化的系譜
昆虫と自然, 12月臨時増刊号, ニュー・サイエンス社， (2021).

FY 2020

Liu and Nakata lab

H. Liu,
Simulation-based Insect-inspired Flight Systems
Insect Science, 42, pp.105-109 (2020)
DOI:10.1016/j.cois.2020.10.001

R. Xu, *T. Nakata, X. Cai, *H. Liu,
Intermittent control strategy can enhance stabilization robustness in bumblebee hovering
Bioinspiration & Biomimetics, 16 016013 (2020)
DOI:10.1088/1748-3190/abbc65

C. Rao, *H. Liu,
Effects of Reynolds number and distribution on passive flow control in owl-inspired leading-edge serrations
Integrative and Comparative Biology, 60-5, pp.1135–1146, (2020)
DOI:10.1093/icb/icaa119

S. Farisenkov, D. Kolomenskiy, T. Engels, N. Lapina, P. Petrov, F. Lehmann, R. Onishi, *H. Liu, A.Polilov,
Aerodynamic performance of a bristled wing of a very small insect
Experiments in Fluids, 61, 194, (2020)
DOI:10.1007/s00348-020-03027-0

T. Xiao, *H. Liu,
Exploring a bumblebee-inspired poweroptimal flapping-wing design for hovering on Mars based on a surrogate model
EJournal of Biomechanical Science and Engineering, 15-2, p.20-00001, (2020)
DOI:10.1299/jbse.20-00001

R. Xu, X. Zhang, *H. Liu,
Effects of wing-to-body mass ratio on insect flapping flights
Physics of Fluids, 33, 021902 (2021)
DOI:10.1063/5.0034806

X. Cai, D. Kolomenskiy, *T. Nakata, and *H. Liu,
A CFD Data-Driven Aerodynamic Model for Fast and Precise Prediction of Flapping Aerodynamics in Various Flight Velocities
Journal of Fluid Mechanics, 33, 021902 (2021)
DOI:10.1017/jfm.2021.68

*T. Nakata, N. Phillips1, P.Simões, I.J. Russell, J. A. Cheney, S.M. Walker, R.J. Bomphrey
Aerodynamic imaging by mosquitoes inspires a surface detector for autonomous flying vehicles
Science, Vol. 368, Issue 6491, pp. 634-637 (2020)
DOI:10.1126/science.aaz9634

P. Zhao, Z. Dong, Y. Jiang, H. Liu, H. Hu, Y. Zhu, D. Zhang
Evaluation of drag force of a thrip wing by using a microcantilever
Journal of Applied Physics, 126, 224701 (2019)
DOI:10.1063/ 1.5126617

Namiki lab

Y. Liu and *A. Namiki,
Articulated Object Tracking by High-Speed Monocular RGB Camera
IEEE Sensors Journal (Early Access), (2020)
DOI:10.1109/JSEN.2020.3032059

Y. Liu, P. Sun, and *A. Namiki,
Target Tracking of Moving and Rotating Object byHigh-Speed Monocular Active Vision
IEEE Sensors Journal, 20-12, pp. 6727-6744,(2020)
DOI:10.1109/JSEN.2020.2976202

並木明夫
ジャグリングロボットとエアホッケーロボット
日本ロボット学会誌, 38-4, pp.307-312,(2020)
DOI:10.7210/jrsj.38.307

Suzuki lab

長谷川 直輝，* 鈴木 智，河村 隆，清水 拓，上野 光，村上弘記
非平面マルチロータヘリコプタの姿勢・位置独立制御
日本ロボット学会誌, 38 巻2 号，pp.74-80,(2020)
DOI:10.7210/jrsj.38.192

Okawa lab

河西高志，* 大川一也
屋外自律移動ロボットのための天空の偏光を利用した方位センサの開発
日本ロボット学会誌, Vol.38, No.8,pp.746-753,(2020)
DOI:10.7210/jrsj.38.746

Kohri lab

M. Kohri
Progress in polydopamine-based melanin mimetic materials for structural color generation
Science and Technology of Advanced Materials, pp.833-848,(2020)
DOI:10.1080/14686996.2020.1852057

*M. Kohri, A. Kobayashi, T. Okoshi, H. Shirasawa, K. Hirai, K. Ujiie, T. Kojima, and K. Kishikawa,
Bright solvent sensor using an inverse opal structure containing melaninmimicking polydopamine
Chemistry Letters,Vol.50, No.1, 106-109, (2021)
DOI:10.1246/cl.200626

T. Iwasaki, S. Harada, T. Okoshi, M. Moriya, T. Kojima, K. Kishikawa, *M. Kohri,
Effect of the polydopamine composite method on structural coloration: comparison of binary and unary assembly of colloidal particles
Langmuir, 36, pp.11880-11887,(2020)
DOI:10.1021/acs.langmuir.0c01904

M. Kohri,
Biomimetic structural color materials based on artificial melanin particles
Journal of Photopolymer Science and Technology, 33-1, pp.111-116,(2020)
DOI:10.2494/photopolymer.33.111

K. Kohaku, M. Inoue, H. Kanoh, T. Taniguchi, K. Kishikawa, and * M. Kohri,
Full-colormagnetic nanoparticles based on holmium-doped polymers
ACS Applied Polymer Materials, pp.1800-1806,(2020)
DOI:10.1021/acsapm.0c00038

M. Yamamoto, K. Ando, M. Inoue, H. Kanoh, M. Yamagami, T. Wakiya, E. Iida, T. Taniguchi, K. Kishikawa, and *M. Kohri,
Poly-β-ketoester particles as a versatile scaffold for lanthanide-doped colorless magnetic materials
ACS Applied Polymer Materials,, pp.2170-2178,(2020)
DOI:10.1021/acsapm.0c00149

Arai lab

中田勇介，荒井幸代,
複数環境におけるエキスパート軌跡を用いたベイジアン逆強化学習
人工知能学会論文誌, 35-1, p. G-J73_1-10,(2020)
DOI:10.1527/tjsai.G-J73

Kubo lab

久保光徳
放射目を臼目とする2つの木摺臼の摺面形状比較ー民具の形から読み取ることができる合理性と造形のアイデアー
民具研究, 162,(2021)

Kato lab

加藤 顕
森林モニタリングのためのレーザー技術
計測と制御, 59-5, pp. 326-330,(2020)
DOI:10.11499/sicejl.59.326

Hudak, A.T., Kato, A.*, Bright, B.C., Loudermilk, E.L., Hawley, C.,Restaino, J., Ottmar, R.D., Prata, G.A., Cabo, C., Prichard, S. J., Rowell E.M. and Weise, D.R.,
Towards spatially explicit quantification of pre- and post-fire fuels and fuel consumption from traditional and point cloud measurements
Forest Science, 66(4) pp. 428-442,(2020)
DOI:10.1093/forsci/fxz085

Kato, A.*, Thau, D., Hudak, A.T. Meigs, G.W. and Moskal, L.M.,
Quantifying fire trends in boreal forests with Landsat time series and self-organized criticality
Forest Science,237,11525,(2020)
DOI:10.1016/j.rse.2019.111525

FY 2019

A. Panta, A. Fisher, A. Mohamed, M. Marino, H. Liu
Low Reynolds number aerodynamics of leading-edge and trailing-edge hinged control surfaces: Part I Statics
Aerospace Science and Technology, Volume 99, (2019)
DOI:10.1016/j.ast.2019.105563

S. Ravi, R. Noda, S. Gagliardi, D. Kolomenskiy, S. Combes, H. Liu, A. Biewener, N. Konow
Modulation of flight muscle recruitment and wing rotation enables hummingbirds to mitigate aerial roll perturbations
Current Biology, S0960-9822(19)31464-2, (2019)
DOI:10.1016/j.cub.2019.11.025

D. Kolomenskiy, S. Ravi, R. Xu, K. Ueyama, T. Jakobi, T. Engels, T. Nakata, J. Sesterhenn, M. Farge, K. Schneider, R. Onishi, H. Liu
Wing morphology and inertial properties of bumblebees
Journal of Aero Aqua Bio-mechanisms, 8(1), 41-47, (2019)
DOI:10.5226/jabmech.8.41

D. Kolomenskiy, S. Ravi, R. Xu, K. Ueyama, T. Jakobi, T. Engels, T. Nakata, J. Sesterhenn, M. Farge, K. Schneider, R. Onishi, H. Liu
The dynamics of passive feathering rotation in hovering flight of bumblebees
Journal of Fluid & Structure, Volume 91, (2019)
DOI:10.1016/j.jfluidstructs.2019.03.021

FY 2018

Loïc Dubois and Satoshi Suzuki
Formation Control of Multiple Quadcopters Using Model Predictive Control
Advanced Robotics, volume 32, issue 19 (2018)
DOI:10.1080/01691864.2018.1470572

FY 2021

劉 浩
Research.comが発表した工学技術系分野のトップ研究者にランクイン
Research.com（日本国内では29位）
2022年3月23日

劉 浩
“羽毛のような羽”持つ小さな昆虫 その独特の飛び方を解明
NHK
2022年1月29日

劉 浩
「骨だけのウチワ」のような翅で飛ぶ昆虫の飛行原理を解明！
ナゾロジー
2022年1月22日

　　

劉 浩
体長約0.4mmの羽毛昆虫が飛べる仕組み、千葉大などが解明
マイナビニュース
2022年1月24日

劉 浩
Tiny feather wing beetle reveals new way to flye
Nature Video
2022年1月1日

鈴木 智
ドローンで草刈りの実証実験 「林業の負担軽減に」 大分 由布
NHK
2021年11月12日

鈴木 智
BlueBeeと千葉大学、九州電力、下刈りドローンの実証試験を実施
ドローンジャーナル
2021年11月10日

桑折 道済
Creating Next-generation Inks that Never Fade
NHK World, Science View
2021年8月24日

桑折 道済
Creating Next-generation Inks that Never Fade
NHK World, Science View
2021年8月24日

大川 一也
虫の方向感覚を参考にした移動ロボット!? 子どもたちがワクワク気分で試乗
チバテレビ/Yahoo!ニュース
2021年7月3日

FY 2020

劉 浩
ハチのように飛ぶ火星探査ロボット
ニュートン7月号
2020年5月26日

中田 敏是
暗闇でも飛ぶ蚊　気流の乱れを察知　千葉大
日本経済新聞
2020年5月24日

中田 敏是
暗闇の蚊　飛べるワケ　気流の乱れ触角で検知
産経新聞
2020年5月24日

中田 敏是
蚊が暗闇でも飛べる理由　気流の変動で障害物検知　身体に備わる超感度センサー　千葉大など解明
科学新聞
2020年5月22日

中田 敏是
真夏の夜の「ぷ〜ん」…羽ばたきの気流頼り
朝日新聞
2020年5月18日

中田 敏是
蚊が暗闇で飛べる秘密わかった
東京新聞
2020年5月17日

中田 敏是
蚊、羽ばたき気流で障害物感知
読売新聞
2020年5月16日

中田 敏是
蚊、なぜ暗闇で自由に飛べる飛べる 羽ばたきの気流で障害感知　千葉大など
北海道新聞
2020年5月11日

中田 敏是
蚊が暗闇で飛べる秘密解明　かすかな気流で障害感知―千葉大など：時事ドットコム
時事通信
2020年5月8日

FY 2019

劉 浩
宅配から開始　ドローン産業集積へ　千葉大、開発支え人材育成
日刊興業新聞
2020年1月12日

昆虫の飛行 立体的に　千葉大、展示で紹介
読売新聞
2019年11月13日

企画展「生き物を観る・知る・真似る」
千葉日報
2019年10月23日

劉 浩
千葉大、生物模したドローン開発　自然環境変化に対応
日刊興業新聞
2019年12月16日