JAIST Repository
https://dspace.jaist.ac.jp/Title

湿潤接着性向上のための形態適応性ソフトコンタクトの機構Author(s)NGUYEN, DANG DUYCitationIssue Date

2024-06

TypeThesis or Dissertation

Text version

ETDURLhttp://hdl.handle.net/10119/19333

RightsDescription

Supervisor: Ho Anh Van, 先端科学技術研究科, 博士

Japan Advanced Institute of Science and Technology

JAPAN ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY

Abstract
Graduate School of Advanced Science and Technology
Doctoral Dissertation

Mechanics of morphologically adaptive soft contact for wet
adhesion enhancement
NGUYEN Dang Duy
This thesis delves into the concept of animal adaptation to various environments through theability to morphologically adapt, often referred to as morphological design. It focuses on thesignificant role of tribological phenomena in different animal species, such as human fingers ingrasping, gecko toes in dry locomotion, and tree frog toes in wet gripping, and how these findings
can be applied to engineering. Wet adhesion, a crucial aspect in tribology, is explored, and its
potential application in robotics is investigated, particularly in the context of stable robot walking
that requires effective gait planning and control. The mechanical properties of the interaction
between robot feet and the ground surface are considered pivotal.
In this research, we propose a mechanics of morphology changeable soft pad for robotic foots
capable of adapting its morphology to the changing terrains that robots encounter. This adaptation
includes optimizing various tribological factors such as friction, adhesion, and particularly wetadhesion when the foot interacts with wet surfaces. The function of actively changing morphology
to adapt to the environment plays an important role in embodied robots. The result proposed inthis thesis is promising to use for the application of embodied robots that perceive theirsurroundings to manipulate objects or move their bodies, process information, and make decisions.
First, I establish a mathematical model based on energy equations to provide insights into theprinciples of morphological changes of the robot foot. I then present two approaches to model thevalue of wet adhesion in preventing slippage for the robot's foot. The first approach simplifies thefoot shape to streamline complex parameters for calculating wet adhesion forces. The secondapproach introduces a more generalized model based on finite element methods to describe wetadhesion forces on a soft body interacting with various ground surfaces. This generalized model
is validated and simulated using the Simulation Open Framework Architecture (SOFA framework).
Subsequently, we present experimental data that corroborates the accuracy of the mathematicalmodels proposed in this research. Finally, we test the application of the morphologically adaptablerobot foot in two scenarios using a separate legged robot and a complete hexapod robot inshowcases. These applications aim to showcase the effectiveness and potential practicality of amorphologically adaptable robot foot.
In conclusion, this research advances our understanding of animal-inspired robotics, particularly
focusing on the significance of morphological adaptability and wet adhesion in robotic locomotion.
The proposed model and its practical application hold promise for the development of robots
capable of efficiently traversing various terrains and adapting to different environments.
Keywords: Tribology, capillary, morphology computation, soft toe pad, animal locomotion, SOFA,
finite element, embodied robot