34 research outputs found
Design and Evaluation of a Bioinspired Tendon-Driven 3D-Printed Robotic Eye with Active Vision Capabilities
The field of robotics has seen significant advancements in recent years,
particularly in the development of humanoid robots. One area of research that
has yet to be fully explored is the design of robotic eyes. In this paper, we
propose a computer-aided 3D design scheme for a robotic eye that incorporates
realistic appearance, natural movements, and efficient actuation. The proposed
design utilizes a tendon-driven actuation mechanism, which offers a broad range
of motion capabilities. The use of the minimum number of servos for actuation,
one for each agonist-antagonist pair of muscles, makes the proposed design
highly efficient. Compared to existing ones in the same class, our designed
robotic eye comprises aesthetic and realistic features. We evaluate the robot's
performance using a vision-based controller, which demonstrates the
effectiveness of the proposed design in achieving natural movement, and
efficient actuation. The experiment code, toolbox, and printable 3D sketches of
our design have been open-sourced
Exploring the Design of a Simultaneous, Parallel, Discrete Joint Control Orthosis for Hand Rehabilitation
This project explores the design of a hand orthosis for rehabilitation which builds upon several pre-existing designs to create a novel mechanism which can provide targeted therapy to one or more discrete joints simultaneously across the lower forearm. This work expands upon and improves the capabilities of hand orthoses to move beyond common design limitations such as controlling only entire fingers or immobilizing crucial regions such as the wrist
Design and fabrication of a modularized humanoid arm with pneumatic artificial muscles
Capstone Project submitted to the Department of Engineering, Ashesi University in partial fulfillment of the requirements for the award of Bachelor of Science degree in Mechanical Engineering, May 2021With increase investment in the development of humanoids, there offers a window of
opportunity to leverage the rapidly growing market of soft robotics in our strides towards more
accurate biomimetic motion and study of humanoids and their applicatory areas.
This project encompasses the systematic design, implementation and testing of a
lightweight low-cost humanoid arm that utilizes Pneumatic Artificial Muscles (PAM). These
muscles do not only exhibit twistable and bendable human-like muscle contractions but
modularized in design to stand as a complete controllable unit which may be dissociated and
mountable on a support frame on its own.
This project achieves the design of a mobile arm unit with total weight of less than 2kg
of which is distributed with one-third the weight being borne on the arm. The realized powerto-
weight ratio of near 5W per kilogram, under an approximate 13.5 litre per minute rate of
pressurization is of desired muscle force, and flex speeds. The McKibben tubing choice of
PAM is experimentally validated under a linear fit for its force-contraction performance.
This design makes considerable strides in cutting down weight, leveraging power, and being
much cheaper than existing solutions. Comparable lightweight arm designs of which some are
commercially available have weights of 38kg (Mitsubishi PA10arm), 14kg (KUKA
lightweight arm), etc., with power-to-weight ratios of near 1W/kg. However, this project
designs cuts down these weights drastically to about 2kg (without any sensory unit yet) and
more than doubles the power to weight ratios mentioned.Ashesi Universit
Anthropomorphically Inspired Design of a Tendon-Driven Robotic Prosthesis for Hand Impairments
This thesis presents the design of a robotic prosthesis, which mimics the morphology of a human hand. The primary goal of this work is to develop a systematic methodology that allows a custom-build of the prosthesis to match the specific requirements of a person with hand impairments. Two principal research questions are addressed toward this goal: 1) How do we cater to the large variation in the distribution of overall hand-sizes in the human population? 2) How closely do we mimic the complex morphological aspects of a biological hand in order to maximize the anthropomorphism (human-like appearance) of the robotic hand, while still maintaining a customizable and manageable design? This design approach attempts to replicate the crucial morphological aspects in the artificial hand (the kinematic structure of the hand skeleton, the shape and aspect ratios of various bone-segments, and ranges of motion). The hand design is partitioned into two parts: 1) A stiff skeleton structure, comprising parametrically synthesized segments that are simplified counterparts of nineteen bone-segmentsโfive metacarpals, five proximal phalanges, four middle phalanges, and five distal phalangesโof the natural hand-skeleton and simplified mechanical substitutes of the remaining eight carpal bones. 2) A soft skin-like structure that encompasses the artificial skeleton to match the cosmetics and compliant features of the natural hand. A parameterized CAD model representation of each synthesized segment is developed by using the feature of design-tables in SolidWorks, which allows easy customization with respect to each person. Average hand measurements available in the literature are used to guide the dimensioning of parameters of each synthesized segment. Tendon-driven actuation of the fingers allows the servo actuators to be mounted remotely, thereby enabling a sleek finger design. A prototype of the robotic hand is constructed by 3D-printing all the parts using an Object 30 Prime 3D printer. Results reported from physical validation experiments of the robotic hand demonstrate the feasibility of the proposed design approach
Design, modeling and implementation of a soft robotic neck for humanoid robots
Menciรณn Internacional en el tรญtulo de doctorSoft humanoid robotics is an emerging field that combines the flexibility and safety of soft
robotics with the form and functionality of humanoid robotics. This thesis explores the potential
for collaboration between these two fields with a focus on the development of soft joints for the
humanoid robot TEO. The aim is to improve the robotโs adaptability and movement, which are
essential for an efficient interaction with its environment.
The research described in this thesis involves the development of a simple and easily transportable
soft robotic neck for the robot, based on a 2 Degree of Freedom (DOF) Cable Driven
Parallel Mechanism (CDPM). For its final integration into TEO, the proposed design is later
refined, resulting in an efficiently scaled prototype able to face significant payloads.
The nonlinear behaviour of the joints, due mainly to the elastic nature of their soft links,
makes their modeling a challenging issue, which is addressed in this thesis from two perspectives:
first, the direct and inverse kinematic models of the soft joints are analytically studied,
based on CDPM mathematical models; second, a data-driven system identification is performed
based on machine learning techniques. Both approaches are deeply studied and compared, both
in simulation and experimentally.
In addition to the soft neck, this thesis also addresses the design and prototyping of a soft
arm capable of handling external loads. The proposed design is also tendon-driven and has a
morphology with two main bending configurations, which provides more versatility compared
to the soft neck.
In summary, this work contributes to the growing field of soft humanoid robotics through
the development of soft joints and their application to the humanoid robot TEO, showcasing the
potential of soft robotics to improve the adaptability, flexibility, and safety of humanoid robots.
The development of these soft joints is a significant achievement and the research presented in this thesis paves the way for further exploration and development in this field.La robรณtica humanoide blanda es un campo emergente que combina la flexibilidad y seguridad
de la robรณtica blanda con la forma y funcionalidad de la robรณtica humanoide. Esta
tesis explora el potencial de colaboraciรณn entre estos dos campos centrรกndose en el desarrollo
de una articulaciรณn blanda para el cuello del robot humanoide TEO. El objetivo es mejorar la
adaptabilidad y el movimiento del robot, esenciales para una interacciรณn eficaz con su entorno.
La investigaciรณn descrita en esta tesis consiste en el desarrollo de un prototipo sencillo
y fรกcilmente transportable de cuello blando para el robot, basado en un mecanismo paralelo
actuado por cable de 2 grados de libertad. Para su integraciรณn final en TEO, el diseรฑo propuesto
es posteriormente refinado, resultando en un prototipo eficientemente escalado capaz de manejar
cargas significativas.
El comportamiemto no lineal de estas articulaciones, debido fundamentalmente a la naturaleza
elรกstica de sus eslabones blandos, hacen de su modelado un gran reto, que en esta tesis
se aborda desde dos perspectivas diferentes: primero, los modelos cinemรกticos directo e inverso
de las articulaciones blandas se estudian analรญticamente, basรกndose en modelos matemรกticos de
mecanismos paralelos actuados por cable; segundo, se aborda el problema de la identificaciรณn
del sistema mediante tรฉcnicas basadas en machine learning. Ambas propuestas se estudian y
comparan en profundidad, tanto en simulaciรณn como experimentalmente.
Ademรกs del cuello blando, esta tesis tambiรฉn aborda el diseรฑo de un brazo robรณtico blando
capaz de manejar cargas externas. El diseรฑo propuesto estรก igualmente basado en accionamiento
por tendones y tiene una morfologรญa con dos configuraciones principales de flexiรณn, lo que
proporciona una mayor versatilidad en comparaciรณn con el cuello robรณtico blando.
En resumen, este trabajo contribuye al creciente campo de la robรณtica humanoide blanda
mediante el desarrollo de articulaciones blandas y su aplicaciรณn al robot humanoide TEO, mostrando el potencial de la robรณtica blanda para mejorar la adaptabilidad, flexibilidad y seguridad
de los robots humanoides. El desarrollo de estas articulaciones es una contribuciรณn
significativa y la investigaciรณn presentada en esta tesis allana el camino hacia nuevos desarrollos
y retos en este campo.Programa de Doctorado en Ingenierรญa Elรฉctrica, Electrรณnica y Automรกtica por la Universidad Carlos III de MadridPresidenta: Cecilia Elisabet Garcรญa Cena.- Secretario: Dorin Sabin Copaci.- Vocal: Martin Fodstad Stole
Design, Control, and Evaluation of a Human-Inspired Robotic Eye
Schulz S. Design, Control, and Evaluation of a Human-Inspired Robotic Eye. Bielefeld: Universitรคt Bielefeld; 2020.The field of human-robot interaction deals with robotic systems that involve
humans and robots closely interacting with each other. With these systems
getting more complex, users can be easily overburdened by the operation
and can fail to infer the internal state of the system or its โintentionsโ. A
social robot, replicating the human eye region with its familiar features and
movement patterns, that are the result of years of evolution, can counter
this. However, the replication of these patterns requires hard- and software
that is able to compete with the human characteristics and performance.
Comparing previous systems found in literature with the human capabili-
ties reveal a mismatch in this regard. Even though individual systems solve
single aspects, the successful combination into a complete system remains
an open challenge. In contrast to previous work, this thesis targets to close
this gap by viewing the system as a whole โ optimizing the hard- and
software, while focusing on the replication of the human model right from
the beginning. This work ultimately provides a set of interlocking building
blocks that, taken together, form a complete end-to-end solution for the de-
sign, control, and evaluation of a human-inspired robotic eye. Based on the
study of the human eye, the key driving factors are identified as the success-
ful combination of aesthetic appeal, sensory capabilities, performance, and
functionality. Two hardware prototypes, each based on a different actua-
tion scheme, have been developed in this context. Furthermore, both hard-
ware prototypes are evaluated against each other, a previous prototype, and
the human by comparing objective numbers obtained by real-world mea-
surements of the real hardware. In addition, a human-inspired and model-
driven control framework is developed out, again, following the predefined
criteria and requirements. The quality and human-likeness of the motion,
generated by this model, is evaluated by means of a user study. This frame-
work not only allows the replication of human-like motion on the specific
eye prototype presented in this thesis, but also promotes the porting and
adaption to less equipped humanoid robotic heads. Unlike previous systems
found in literature, the presented approach provides a scaling and limiting
function that allows intuitive adjustments of the control model, which can
be used to reduce the requirements set on the target platform. Even though
a reduction of the overall velocities and accelerations will result in a slower
motion execution, the human characteristics and the overall composition of
the interlocked motion patterns remain unchanged
Large Deformable Soft Actuators Using Dielectric Elastomer and Origami Inspired Structures
There have been significant developments in the field of robotics. Significant development consists of new configurations, control mechanisms, and actuators based upon its applications. Despite significant improvements in modern robotics, the biologically inspired robots has taken the center stage. Inspired by nature, biologically inspired robots are called โsoft robotsโ. Within these robots lies a secret ingredient: the actuator. Soft robotic development has been driven by the idea of developing actuators that are like human muscle and are known as โartificial muscleโ. Among different materials suitable for the development of artificial muscle, the dielectric elastomer actuator (DEA) is capable of large deformation by applying an electric field. Theoretical formulation for DEA was performed based upon the constitutive hyperelastic models and was validated by using finite element method (FEM) using ABAQUS. For FEM, multistep analysis was performed to apply pre-stretch to the membrane before applying actuation voltage. Based on the validation of DEA, different configurations of DEA were investigated. Helical dielectric elastomer actuator and origami dielectric elastomer actuator were investigated using theoretical modeling. Comparisons were made with FEM to validate the model. This study focus on the theoretical and FEM analysis of strain within the different configuration of DEA and how the actuation strain of the dielectric elastomer can be translated into contraction and/or bending of the actuator
์ฌ๋ ๊ทผ๊ณจ๊ฒฉ ํน์ฑ์ ๋ฐ์ํ ๋ก๋ด ์๊ฐ๋ฝ ์ค๊ณ
ํ์๋
ผ๋ฌธ(๋ฐ์ฌ) -- ์์ธ๋ํ๊ต๋ํ์ : ์ตํฉ๊ณผํ๊ธฐ์ ๋ํ์ ์ตํฉ๊ณผํ๋ถ(์ง๋ฅํ์ตํฉ์์คํ
์ ๊ณต), 2023. 2. ๋ฐ์ฌํฅ.What the manipulator can perform is determined by what the end-effectors, including the robotic hand, can do because it is the gateway that directly interacts with the surrounding environment or objects. In order for robots to have human-level task performance in a human-centered environment, the robotic hand with human-hand-level capabilities is essential. Here, the human-hand-level capabilities include not only force-speed, and dexterity, but also size and weight. However, to our knowledge, no robotic hand exists that simultaneously realizes the weight, size, force, and dexterity of the human hand and continues to remain a challenge. In this thesis, to improve the performance of the robotic hand, the modular robotic finger design with three novel mechanisms based on the musculoskeletal characteristics of the human hand was proposed.
First, the tendon-driven robotic finger with intrinsic/extrinsic actuator arrangement like the muscle arrangement of the human hand was proposed and analyzed. The robotic finger consists of five different tendons and ligaments. By analyzing the fingertip speed while a human is performing various object grasping motions, the actuators of the robotic finger were separated into intrinsic actuators responsible for slow motion and an extrinsic actuator that performs the motions requiring both large force and high speed.
Second, elastomeric continuously variable transmission (ElaCVT), a new concept relating to continuously variable transmission (CVT), was designed to improve the performance of the electric motors remaining weight and size and applied as an extrinsic actuator of the robotic finger. The primary purpose of ElaCVT is to expand the operating region of a twisted string actuator (TSA) and duplicate the force-velocity curve of the muscles by passively changing the reduction ratio according to the external load applied to the end of the TSA. A combination of ElaCVT and TSA (ElaCVT-TSA) is proposed as a linear actuator. With ElaCVT-TSA, an expansion of the operating region of electric motors to the operating region of the muscles was experimentally demonstrated.
Finally, as the flexion/extension joints of the robotic finger, anthropomorphic rolling contact joint, which mimicked the structures of the human finger joint like tongue-and-groove, and collateral ligaments, was proposed. As compliant joints not only compensate for the lack of actuated degrees of freedom of an under-actuated system and improve grasp stability but also prevent system failure from unexpected contacts, various types of compliant joints have been applied to end-effectors. Although joint compliance increases the success rate of power grasping, when the finger wraps around large objects, it can reduce the grasping success rate in pinch gripping when dealing with small objects using the fingertips. To overcome this drawback, anthropomorphic rolling contact joint is designed to passively adjust the torsional stiffness according to the joint angle without additional weight and space. With the anthropomorphic rolling contact joint, the stability of pinch grasping improved.์๋์ดํฉํฐ๋ ๋ก๋ด๊ณผ ์ฃผ๋ณ ํ๊ฒฝ์ด ์ํธ์์ฉํ๋ ํต๋ก๋ก ๋งค๋ํฐ๋ ์ดํฐ๊ฐ ์ํํ ์ ์๋ ์์
์ ์๋์ดํํฐ์ ์ฑ๋ฅ์ ์ ํ๋๋ค. ์ฌ๋ ์ค์ฌ์ ํ๊ฒฝ์ ๋ก๋ด์ด ์ ์ฉ๋์ด ์ฌ๋ ์์ค์ ๋ค์ํ ์์
์ ์ํํ๊ธฐ ์ํด์๋ ์ฌ๋ ์ ์์ค์ ์ฑ๋ฅ์ ๊ฐ๋ ๋ก๋ด ์์ด ํ์์ ์ด๋ฉฐ ์ฌ๋ ์ ์์ค์ ์ฑ๋ฅ์ ๋จ์ํ ํ-์๋, ์์ ๋๋ง์ ํฌํจํ๋ ๊ฒ์ด ์๋ ํฌ๊ธฐ์ ๋ฌด๊ฒ ๊ทธ๋ฆฌ๊ณ ๋ฌผ์ฒด ์กฐ์์ ๋์์ ์ฃผ๋ ์ฌ๋ฌ ์ ํน์ฑ๋ ํฌํจํ๋ค. ๊ทธ๋ฌ๋ ํ์ฌ๊น์ง ์ฌ๋ ์ ์์ค์ ๋ฌด๊ฒ, ํฌ๊ธฐ, ํ ๊ทธ๋ฆฌ๊ณ ์์ ๋๋ฅผ ๋ชจ๋ ๋ง์กฑ์ํค๋ ๋ก๋ด ์์ ๊ฐ๋ฐ๋์ง ์์์ผ๋ฉฐ ์ฌ์ ํ ๋์ ์ ์ธ ๊ณผ์ ๋ก ๋จ์์๋ค. ๋ณธ ๋
ผ๋ฌธ์์๋ ๋ก๋ด ์๊ฐ๋ฝ์ ์ฑ๋ฅ์ ํฅ์ํ๊ธฐ ์ํ์ฌ ์ฌ๋์ ๊ทผ๊ณจ๊ฒฉ ํน์ฑ์ ๋ฐ์ํ ์ธ ๊ฐ์ง์ ์๋ก์ด ๋ฉ์ปค๋์ฆ์ ์ ์ํ๊ณ ์ด๋ฅผ ํตํฉํ ๋ชจ๋ํ ๋ก๋ด ์๊ฐ๋ฝ ๊ตฌ์กฐ๋ฅผ ๋ณด์ธ๋ค.
์ฒซ ๋ฒ์งธ๋ก, ์ฌ๋์ ์ ๊ทผ์ก ๋ฐฐ์น์ ์ ์ฌํ ๋ด์ฌ/์ธ์ฌ ๊ตฌ๋๊ธฐ ๋ฐฐ์น๋ฅผ ์ ์ฉํ ํ์ค ๊ตฌ๋ ๋ก๋ด ์๊ฐ๋ฝ ๊ตฌ์กฐ๋ฅผ ์ ์ํ๊ณ ๋ถ์ํ๋ค. ๋ก๋ด ์๊ฐ๋ฝ์ ๋ค์ฏ ๊ฐ์ ์๋ก ๋ค๋ฅธ ํ์ค๊ณผ ์ธ๋๋ก ๊ตฌ์ฑ๋๋ค. ์ฌ๋ ์๋์ ๋ถ์์ ๊ธฐ๋ฐํ์ฌ ๋ก๋ด ์๊ฐ๋ฝ์ ๊ตฌ๋๊ธฐ๋ ๋๋ฆฐ ์๋๋ฅผ ๋ด๋นํ๋ ๋ด์ฌ ๊ตฌ๋๊ธฐ์ ๋น ๋ฅด๊ณ ํฐ ํ์ด ๋ชจ๋ ์๊ตฌ๋๋ ์ธ์ฌ ๊ตฌ๋๊ธฐ๋ก ๊ตฌ๋ถ๋๋ค.
๋ ๋ฒ์งธ๋ก, ๊ตฌ๋๊ธฐ์ ํฌ๊ธฐ์ ๋ฌด๊ฒ๋ฅผ ์ ์งํ๋ฉฐ ์ฑ๋ฅ์ ํฅ์ํ๊ธฐ ์ํ์ฌ ์๋ก์ด ๊ฐ๋
์ ๋ฌด๋จ ๋ณ์๊ธฐ Elastomeric Continuously Variable Transmission (ElaCVT) ์ ์ ์ํ๊ณ ์ด๋ฅผ ๋ก๋ด ์๊ฐ๋ฝ์ ์ธ์ฌ ๊ตฌ๋๊ธฐ์ ์ ์ฉํ์๋ค. ElaCVT๋ ์ ํ ๊ตฌ๋๊ธฐ์ ์๋ ์์ญ์ ํ์ฅํ๊ณ ์ถ๋ ฅ๋จ์ ๊ฐํด์ง๋ ์ธ๋ถ ํ์ค์ ๋ฐ๋ผ ๊ฐ์๋น๋ฅผ ์๋์ ์ผ๋ก ๋ณ๊ฒฝํ์ฌ ๊ทผ์ก์ ํ-์๋ ๊ณก์ ์ ๋ชจ์ฌํ ์ ์๋ค. ๋ณธ ์ฐ๊ตฌ์์๋ ๊ทผ์ก์ ํน์ฑ์ ๋ชจ์ฌํ๊ธฐ ์ํด ์ ํ ์ก์ถ์์ดํฐ๋ก ElaCVT์ ์ค ๊ผฌ์ ๋ฉ์ปค๋์ฆ์ ์ ์ฉํ ElaCVT-TSA๋ฅผ ์ ์, ๊ทผ์ก์ ๋์ ์์ญ์ ๋ชจ์ฌํ ์ ์์์ ๋ณด์๋ค.
๋ง์ง๋ง์ผ๋ก ๋ก๋ด ์๊ฐ๋ฝ์ ๋ชจ๋ ๊ตฝํ/ํผ์นจ ๊ด์ ์ ์ ์ฉ๋ ์ฌ๋์ ๊ด์ ๊ตฌ์กฐ๋ฅผ ๋ชจ์ฌํ ์ ์ฐ ๊ตฌ๋ฆ ์ ์ด ๊ด์ (Anthropomorphic Rolling Contact joint)์ ์ ์ํ๋ค. Anthropomorphic rolling contact joint๋ ์ฌ๋ ๊ด์ ์ tongue-and-groove ํ์๊ณผ collateral ligament๋ฅผ ๋ชจ์ฌํ์ฌ ๊ด์ ์ ์์ ์ฑ์ ํฅ์์์ผฐ๋ค. ๊ธฐ์กด์ ์ ์ฐ ๊ด์ ๊ณผ ๋ฌ๋ฆฌ ๊ด์ ์ด ํด์ง ์ํ์์๋ ์ ์ฐํ ์ํ๋ฅผ ์ ์งํ๋ฉฐ ๊ตฝํ์ง ์ํ์์๋ ๊ฐ์ฑ์ด ์ฆ๊ฐํ๋ค๋ ํน์ง์ ๊ฐ๋๋ค. ํนํ, ๊ฐ์ฑ ๋ณํ์ ๋ณ๋์ ๊ตฌ๋๊ธฐ๊ฐ ์๊ตฌ๋์ง ์์ ๊ธฐ์กด์ ๊ด์ ์์ ๋ฌด๊ฒ, ํฌ๊ธฐ ์ฆ๊ฐ ์์ด ํด๋น ํน์ง ๊ตฌํ์ด ๊ฐ๋ฅํ๋ค. ์ด๋ ๋ก๋ด ์๊ฐ๋ฝ์ ์ ์ฉ๋์ด ์๊ฐ๋ฝ์ ํด๊ณ ๋ฌผ์ฒด๋ฅผ ํ์ํ๋ ๊ณผ์ ์์๋ ์ถฉ๊ฒฉ์ ํก์ํ์ฌ ์์ ์ ์ธ ์ ์ด์ ๊ตฌํํ ์ ์์ผ๋ฉฐ ๋ฌผ์ฒด๋ฅผ ํ์งํ๋ ๊ณผ์ ์์๋ ์๊ฐ๋ฝ์ ๊ตฝํ ๊ฐ์ธํ๊ฒ ๋ฌผ์ฒด๋ฅผ ํ์งํ ์ ์๊ฒ ํ๋ค. Anthropomorphic rolling contact joint๋ฅผ ์ ์ฉํ ๊ทธ๋ฆฝํผ๋ฅผ ์ด์ฉํ์ฌ ์ ์ํ๋ ๊ฐ๋ณ ๊ฐ์ฑ ์ ์ฐ ๊ด์ ์ด pinch grasping์ ํ์ง ์์ ์ฑ์ ๋์์ ๋ณด์๋ค.1 INTRODUCTION 1
1.1 MOTIVATION: ROBOTIC HANDS 1
1.2 CONTRIBUTIONS OF THESIS 10
1.2.1 Intrinsic/Extrinsic Actuator arrangement 11
1.2.2 Linear actuator mimicking human muscle properties 11
1.2.3 Flexible rolling contact joint 12
2 ROBOTIC FINGER STRUCTURE WITH HUMAN-LIKE ACTUATOR ARRANGEMENT 13
2.1 ANALYSIS OF HUMAN FINGERTIP VELOCITY 14
2.2 THE ROBOTIC FINGER WITH INTRINSIC/EXTRINSIC ACTUATORS 18
2.2.1 The structure of proposed robotic finger 18
2.2.2 Kinematics of the robotic finger 20
2.2.3 Tendons and Ligaments of the proposed robotic finger 26
2.2.4 Decoupled fingertip motion in the sagittal plane 28
3 ELASTOMERIC CONTINUOUSLY VARIABLE TRANSMISSION COMBINED WITH TWISTED STRING ACTUATOR 35
3.1 BACKGROUND & RELATED WORKS 35
3.2 COMPARISON OF OPERATING REGIONS 40
3.3 DESIGN OF THE ELASTOMERIC CONTINUOUSLY VARIABLE TRANSMISSION 42
3.3.1 Structure of ElaCVT 42
3.3.2 Design of Elastomer and Lateral Disc 43
3.3.3 Advantages of ElaCVT 48
3.4 PERFORMANCE EVALUATION 50
3.4.1 Experimental Setup 50
3.4.2 Contraction with Fixed external load 50
3.4.3 Contraction with Variable external load 55
3.4.4 Performance variation of ElaCVT over long term usage 55
3.4.5 Specifications and Limitations of ElaCVT-TSA 59
4 ANTHROPOMORPHIC ROLLING CONTACT JOINT 61
4.1 INTRODUCTION: COMPLIANT JOINT 61
4.2 RELATED WORKS: ROLLING CONTACT JOINT 65
4.3 ANTHROPOMORPHIC ROLLING CONTACT JOINT 67
4.3.1 Fundamental Components of ARC joint 69
4.3.2 Advantages of ARC joint 73
4.4 TORSIONAL STIFFNESS EVALUATION 75
4.4.1 Experimental Setup 75
4.4.2 Design and Manufacturing of ARC joints 77
4.4.3 Torsional Stiffness Change according to Joint Angle and Twist Angle 79
4.5 TORSIONAL STIFFNESS WITH JOINT COMPRESSION FORCE DUE TO TNESION OF TENDONS 80
4.6 TORSIONAL STIFFNESS WITH LUBRICATION STRUCTURE 82
4.7 GRASPING PERFORMANCE COMPARISON OF GRIPPERS WITH DIFFERENT ARC JOINTS 86
5 CONCLUSIONS 92
Abstract (In Korean) 107๋ฐ