Experimental study of control method of undulating robot based on environmental adaptability of nematode

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K14699
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 20020:Robotics and intelligent system-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: Yamano Akio 大阪府立大学, 工学(系)研究科(研究院), 助教 (90844184)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: バイオミメティクス

Outline of Final Research Achievements

Numerical models were developed to reproduce the experimental results by conducting swimming experiments in water (1.31 mm^2/s), lubricating oil I (2270 mm^2/s), and oil II (3270 mm^2/s) and by identifying the fluid forces acting on the swimming body.
Next, we calculated the trade-off relationship between power consumption and swimming velocity as an evaluation function under the condition that a phase-shifted sinusoidal torque is input to each joint in each viscous fluid used in the experiments. The wavelength of the swimming motion tended to decrease as the viscosity of the fluid increased. The adaptive motion that realizes an appropriate swimming pattern according to the viscosity of the fluid has been successfully generated in an experimental model, and we plan to explore the control parameters of the adaptive motion using self-excited oscillation.

Free Research Field

機械力学

Academic Significance and Societal Importance of the Research Achievements

泳動の最適化およびモデルベース制御において，計算コストの小さい数値解析モデルは有用である．提案手法は，計測された挙動より推進体に作用する流体力を同定するものであり，様々な粘性流体中を泳動する複雑な断面を有する推進体においても，数値解析モデルを構築することが容易になる．また，うねり運動により接線方向の抗力が増大する現象が実験的に確認できた．
最適化計算では，流体の粘度の増加と共に位相差が増加する傾向が確認された．高粘性流体ではうねり泳動の波長の小さい方が推進効率が高いことを示しており，生物のセンチュウにおいても同様の運動が観察されている．適応運動の意義の解明の助けになると考えられる．