KIKUCHI Lab

Chiba Institute of Technology, Faculty of Advanced Engineering

>>Jump to Japanese pages

[KIKUCHI Labratry] >> Research >> A Butterfly-style Flapping Robot

A Butterfly-style Flapping Robot

Flying robots offer great promise as observation systems in hazardous environments because they are not affected by ground conditions. Although several flying devices with different methods of lift and propulsion exist, such as jet planes, airships and helicopters, for the important abilities of being able to turn at nearly right angles and to accelerate to over several Gs at the moment of take-off, "flapping", as performed by living creatures, offers many advantages. Above all, imagine the scene such as smoothly passing through a narrow space such as a pipe or gap between debris, the flapping mechanisms used by insects is very attractive. It is generally considered that flying insects acquire lift through interaction with the vortex around the wing boundary generated by flapping, and therefore, many researchers have recently been studying this mechanism. However, this Structure-Fluid coupled problem is highly complex and difficult -- for instance, the deformation of elastic wings by the fluid and flow field varies with the wing motion -- and thus it has not yet been fully solved.

Meanwhile, the ability of insects to control their flight is very high, despite the fact that the number of neurons in an insect brain is barely of the order of 10^5 to 10^6 (We have 10^10 to 10^11). Hence, they must use the characteristics of their own structure (i.e., "Morphology") very effectively, implying that a control system can be simplified by employing the dynamics of the structural system. The design concept of this study is that flying insects do not require a complicated control system, but instead have structural characteristics with which lift is generated through simple body vibrations, i.e., flapping. Hence the essence of the design principle is that the control system and the structural system, that is, the intelligence and the morphology, are in balance. This design principle may be particularly significant for micromachines where high-end CPUs, sensors and actuators are difficult to use.

From the above standpoint, we are developing a cm-scale flapping robot that utilizes the dynamics of its structural system and uses a simplified control system. We focus on a swallowtail butterfly with only a few DOF and a low flapping frequency as a flapping model.

The points we are tackling now are as follows:

1.Analysis of the body and wing motions during takeoff using three-dimensional high-speed camera system.
2.Investigation of the flight performance depending on the structural parameters such as abdomen mass ratio, wing elasticity, and wing aspect ratio.
3.Motion analysis by the numerical simulation considering body motion, elastic deformation of wings, and flow field.
4.Development of the hardware balancing the structural system and the control system.

Related Papers:
.Taro Fujikawa, Kazuaki Hirakawa, Shinnosuke Okuma, Takamasa Udagawa, Satoru Nakano, Koki Kikuchi, Development of a small flapping robot: Motion analysis during takeoff by numerical simulation and experiment , MECHANICAL SYSTEMS AND SIGNAL PROCESSING(MSSP), ELSEVIER, Vol.22, Issue 6, pp.1304-1315, (2008-8), (Full paper).
.Masahiro SHINDO, Taro FUJIKAWA, Koki KIKUCHI: Analysis of Roll Rotation Mechanism of a Butterfly for Development of a Small Flapping Robot?CAmerican Transactions on Engineering & Applied Sciences, October 2014, Vol.3(4), pp.233-250, (2014), (Full paper).
.Taro FUJIKAWA, Masahiro SHINDO, Koki KIKUCHI: Motion Analysis of Pitch Rotation Mechanism for Posture Control of Butterfly-style Flapping Robot?CAmerican Transactions on Engineering & Applied Sciences, October 2014, Vol.3(4), pp.251-263, (2014), (full paper).

 Observation by High-Speed Camera
 Flow Visualization
 Numerical Simulation
 Harware Experiments
 Pictures

© K.Kikuchi <Kikuchi Laboratory> - Since April 2004