Flexible sliding actuator using a flat tube and its application to the rescue operation
This paper proposes a novel flexible sliding actuator driven by fluid power. The actuator called Λ -drive is basically composed of a flat tube and a slider. In the slider the tube is bent, then the buckling point occurs, which helps to cut off the fluid passage in order to provide the driving force to the slider when pressurizing one side of the tube. The proposed actuator is applicable to not only the straight path but the spiral and the curved one as well. Moreover, the design method to drive stably and the analysis of the output force are discussed in this paper. Finally, “Fluid Ropeway” is also proposed as the application of Λ-drive aiming to search and rescue survivors in the half collapsed houses, and its feasibility is verified through the experiment.
DEVELOPMENT OF A FLEXIBLE PNEUMATIC ACTUATOR WITH A FLEXIBLE TUBE
Recently, virtual reality systems have been flourishing as an interactive information technology. However, current virtual reality systems are not enough to realize a force feedback system for hands, arms, legs and so on. Furthermore, due to the ageing in Japanese society and the decreasing birthrate, an increasing problem of providing nursing care for the elderly has occurred. As a result, it is necessary to develop systems to aid in nursing care. The actuators necessary for such a feedback system, as for power assisted nursing care of the elderly, need to be flexible so as not to injure the human body. The purpose of our study is to develop a flexible and lightweight actuator which can be safe enough to be mounted on the human body. In this study, we propose a new type of flexible pneumatic actuator that can be used even if the actuator is deformed by external force. We tested two types of flexible pneumatic cylinder. One type uses rubber balls and the other type uses Y-ring type gaskets to seal the cylinder head. The elastic pneumatic cylinder consists of a flexible tube as a cylinder and an elastic cylinder head consisting of rubber balls and gaskets. We investigated the relation between generated force and supply pressure for the bent cylinder tube. And we proposed the analytical model of the actuator and identified system parameters of the actuator in order to design it. As a result, we confirmed that the tested flexible pneumatic cylinder was very useful to be applied as an actuator that can be set on the human body with advantages of flexibility, lightweight and large ratio of the generated force to weight.
Rational Design, Synthesis and Evaluation of γ-CD-Containing Cross-Linked Polyvinyl Alcohol Hydrogel as a Prednisone Delivery Platform
This study describes the in-silico rational design, synthesis and evaluation of cross-linked polyvinyl alcohol hydrogels containing γ-cyclodextrin (γ-CDHSAs) as platforms for the sustained release of prednisone (PDN). Through in-silico studies using semi-empirical quantum mechanical calculations, the effectiveness of 20 dicarboxylic acids to generate a specific cross-linked hydrogel capable of supporting different amounts of γ-cyclodextrin (γ-CD) was evaluated. According to the interaction energies calculated with the in-silico studies, the hydrogel made from PVA cross-linked with succinic acids (SA) was shown to be the best candidate for containing γ-CD. Later, molecular dynamics simulation studies were performed in order to evaluate the intermolecular interactions between PDN and three cross-linked hydrogel formulations with different proportions of γ-CD (2.44%, 4.76% and 9.1%). These three cross-linked hydrogels were synthesized and characterized. The loading and the subsequent release of PDN from the hydrogels were investigated. The in-silico and experimental results showed that the interaction between PDN and γ-CDHSA was mainly produced with the γ-CDs linked to the hydrogels. Thus, the unique structures and properties of γ-CDHSA demonstrated an interesting multiphasic profile that could be utilized as a promising drug carrier for controlled, sustained and localized release of PDN.