• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.1255-1255
• /
• 2004

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.36.1-36
• /
• 2002

$\textbullet$ Actuator based on dielelectric elastomer $\textbullet$ Antagonistic configuration $\textbullet$ Musclelike characteristics $\textbullet$ Quasi-static and dynamic analysis $\textbullet$ Compliance control $\textbullet$ Robotic actuators

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.06a
• /
• pp.85-86
• /
• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.244-247
• /
• 2005

Although several artificial disc designs have been developed for the treatment of discogenic low back pain and used clinically, biomechanical change with its implantation seldom studied. To evaluate the effect of artificial disc implantation on the biomechanics of lumbar spinal unit, nonlinear three-dimensional finite element model of L1-L5, S1 was developed and strain and stress of vertebral body and surrounding spinal ligaments were predicted. Intact osteoligamentous L1-L5, S1 model was created with 1-mm CT scan of a volunteer and known material property of each element were applied. This model also includes the effect of local muscles which was modeled with pre-strained spring elements. The intact model was validated with reported biomechanical data. Two models implanted with artificial discs, SB Charite or Prodisc, at L4/5 via anterior approach were also developed. The implanted model predictions were compared with that of intact model. Angular motion of vertebral body, force on spinal ligaments, facet joint contact force with $2\sim12$ Nm flexion-extension moment.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.5B no.2
• /
• pp.118-122
• /
• 2005

Electro-chemo-mechanical devices or artificial muscles based on conducting polymers (CP) are presented as bilayers, CP/adhesive polymer, or as triple layers, CP/adhesive polymer/CP. Those soft and wet materials, working in aqueous solutions of a salt, mimic the composition of most organs from animals. Under electrochemical control, so working as new electrical machines, they produce continuous, reverse and elegant bending movements, mimicking those produce by animal muscles. By means of the current a perfect controls of the movement rate is attained giving soft and continuous movements. Muscles able to sense the chemical and mechanical conditions of work or muscle having tactile sense, as will be presented here, are being developed. All of them are founded on the non-stoichiometric nature of the soft and wet materials.

• Journal of the Korean Ceramic Society
• /
• v.43 no.4 s.287
• /
• pp.203-206
• /
• 2006

Polyacrylonitrile (PAN) nanofibers, which are pH-sensitive and exhibit soft actuation as a linear actuator and artificial muscles, were prepared by electrospinning to investigate the effect of viscosity on the morphology of PAN fibers. Experimental results revealed that higher viscosity is critical for the formation of unbeaded nanofibers because surface tension is almost constant throughout the experiment. Uniform, smooth, and continuous fibers with diameters of about 700 nm were achieved for the 10 wt% PAN fibers at a flow rate of 0.5 mL/h and an electric field of 0.875 kV/cm.

• Electronics and Telecommunications Trends
• /
• v.34 no.4
• /
• pp.108-116
• /
• 2019

Electro-active polymers and dielectric elastomers have many intriguing properties that enable smart interfaces and electrically tunable optical systems, such as haptic feedback devices, artificial muscles, and expansion-tunable optical elements. These device classes are of great interest owing to their promising roles in next-generation technologies including virtual or augmented reality, human sensing and muscular enhancement, and artificial skins. In this report, we review basic principles, current state-of-the-art techniques, and future prospects of electro-active and dielectric elastomer technology. We describe chemical and physical properties of the most promising polymer substances, essential elementary architectures for artificial muscle-like functionalities, and their applications to haptic interfaces, muscular enhancement, and focus-tunable optical elements.

• The Journal of Korea Robotics Society
• /
• v.16 no.1
• /
• pp.17-22
• /
• 2021

Soft robot research has been actively conducted due to the advantages of soft materials that have less motion restrictions and higher energy efficiency compared to rigid robots. In particular, soft robots are being applied in more and more diverse fields, and the need for soft robots is increasing, especially when dealing with soft or deformable objects that rigid robots cannot perform. Various soft robots are being developed, and studies on artificial muscles with versatility, seamless integration with sensing, and self-healing capabilities are being proposed. In this study, we propose one of the most simple rectangular shaped HASEL (Hydraulically amplified self-healing electrostatic) actuators and compare the performance according to shape deformation such as the size or ratio of actuators and electrodes. Developing these actuators can be used in many ways for artificial muscles in soft robotics.

• Advanced Composite Materials
• /
• v.18 no.4
• /
• pp.327-338
• /
• 2009

In this paper, through an evaluation process conducted on several designs of mini-LIPCA (Lightweight Piezo-Composite curved Actuator), an optimal design of a mini-LIPCA has been proposed. Comparing with the LIPCA-C2, the design of the mini-LIPCA comes with reduced overall size and a thinner active layer. Since a variation in the number and lay-up of fiber composite layers may strongly affect the performance of the device, one is able to configure several designs of mini-LIPCA. The evaluation process is then followed in order to determine a configuration which characterizes the possibly optimal performance. That is, a design of a mini-LIPCA is said to be optimal if it is capable of producing a maximum out-of-plane displacement. The size of the LIPCA to be investigated was selected to be $10\;mm\;{\times}\;20\;mm$ in which the thickness of PZT plate is about 0.1 mm. The thickness of glass/epoxy and carbon/epoxy are about 0.09 mm and 0.1 mm, respectively. The evaluation process has been conducted thoroughly, i.e., analytical estimation, numerical approximation and the experimental measurement are all involved. Firstly, the design equation was used to calculate essential parameters of proposed lay-up configurations. Secondly, ANSYS, a commercial FEA package, was utilized to estimate displacement outputs of the actuators upon being excited. Finally, experimental measurements were able to verify the predicted results.

• International Journal of Aeronautical and Space Sciences
• /
• v.12 no.1
• /
• pp.69-77
• /
• 2011

A peristaltic micropump with lightweight piezo-composite actuator (LIPCA) membrane valves is presented. The micropump contained three cylinder chambers that were connected by microchannels and two active membrane valves. A circular miniature LIPCA was developed and manufactured to be used as actuating diaphragms. The LIPCA diaphragm acted as an active membrane valve that alternate between open and closed positions at the inlet and outlet in order to produce high pumping pressure. In this LIPCA, a lead zirconium titanate ceramic with a thickness of 0.1 mm was used as an active layer. The results confirmed that the actuator produced a large out-of-plane deflection. During the design process, a coupled field analysis was conducted in order to predict the actuating behavior of the LIPCA diaphragm; the behavior of the actuator was investigated from both a theoretical and experimental perspective. The active membrane valve concept was introduced as a means for increasing pumping pressure, and microelectromechanical system techniques were used to fabricate the peristaltic micropump. The pumping performance was analyzed experimentally in terms of the flow rate, pumping pressure and power consumption.