Fish-Like Robot Encapsulated by a Plastic Film

Underwater robots are currently utilized to evaluate water quality and the undersea landscape. Small-sized underwater robots are especially useful in improving the spatial resolution of the measurements, yielding high-quality data. This chapter describes a small-sized fish-like robot, with its surface composed of a flexible thin plastic film. Its internal components, including an actuator, could be encapsulated in the plastic film using a vacuum packaging machine. To simplify the waterproofing and pressure resistance properties of the fish-like robot, its internal components can be filled with insulating fluid. The plastic film on the surface has electromagnetic-wave-transmitting properties, allowing sensors to be arranged within the device, enabling assessment of its autonomous locomotion using infrared sensors. Robot attitude can be altered, based on geography of its internal components, floating blocks, and insulating fluid. This attitude could be especially determined by the differences in densities between the floating block and insulating fluid. Evaluation of attitude control showed that an insulating fluid heavier than water allows a large variation

Dynamic Modeling of a Serial Link Robot Laminated with Plastic Film

This chapter presents serial link robots laminated with a plastic film, a derivation of the equations of motion of the laminated robots, and numerical simulation. Recently, to become capable of wide application for several serial link robots that work outside, waterproofing and dustproofing techniques are required. We have proposed a robot packaging method to improve waterproof and dustproof properties of serial link robots. Using the proposed packaging method, rigid links with some active joints are loosely laminated with plastic film to protect the links from dust and water. In the next step of our research, we must derive the equations of motion of the laminated robots for the design and performance improvement from the viewpoint of high speed and high energy efficiency. We assume a plastic film as a closed-loop link structure with passive joints in this chapter. A rigid serial link (fin) connected with a motor-actuated joint moves a closed-loop link structure with passive joints. We numerically investigate the influence of the flexural rigidity of a plastic film on the motion of the rigid fin. This research not only contributes to the lamination techniques but also develops a novel application of waterproofing and dustproofing techniques in robotics

Loosely Coupled Joint Driven by SMA Coil Actuators”,

Abstract-We introduce a robotic prototype of an arm with a loosely coupled joint, modeled on the human joint. A viscoelastic object functions as cartilage and soft actuators as muscles. First, we show that although viscoelastic object affords smooth movement owing to shift in the center of rotation, the repeat accuracy of the joint is poor under open-loop control. The repeat accuracy was much improved by visual feedback. Under P control, the prototype was shown to be highly robust against mechanical disturbance owing to its good mechanical compliance

Successful Vancomycin Dose Adjustment in a Sepsis patient with Bacterial Meningitis Using Cystatin C

Cystatin C-guided vancomycin (VCM) dosing is useful in critically ill patients. Its usefulness in septic patients with bacterial meningitis remains unknown, as there are no published reports. In this study, we sought to clarify its benefit. Cystatin C was used to guide VCM dosing in a septic bacterial meningitis patient with normal kidney function, according to therapeutic drug monitoring (TDM). Using cystatin C, the Bayesian method-based TDM made optimal VCM dosing possible, and decreased the predicted error (4.85 mg/L) compared to serum creatinine (16.83 mg/L). We concluded TDM of VCM using cystatin C can be considered in sepsis patients with bacterial meningitis with normal kidney function

Evaluation of oral immunotherapy efficacy and safety by maintenance dose dependency: A multicenter randomized study

Background Generally, oral immunotherapy (OIT) aims for daily administration. Recently, the efficacy of treatment with OIT at a low dose has been reported. However, the optimal dose and the evaluation of dose-dependent OIT outcome have not been described. Methods A multicenter, parallel, open-labeled, prospective, non-placebo controlled, randomized study enrolled 101 Japanese patients for treatment with OIT. We hypothesized that target dose OIT would induce short-term unresponsiveness (StU) earlier than reduced dose OIT. StU was defined as no response to 6200 mg whole egg, 3400 mg milk, and 2600 mg wheat protein, as evaluated by oral food challenge after 2-week ingestion cessation. To compare the two doses of OIT efficacy, the maximum ingestion doses during the maintenance phase of OIT were divided into 100%-dose or 25%-dose groups against their target StU dose, respectively. A total of 51 patients were assigned to the 100%-dose group [hen's egg (HE) = 26, cow's milk (CM) = 13, wheat = 12] and 50 to the 25%-dose group (HE = 25, CM = 13, wheat = 12). Primary outcome was established by comparing StU at 1 year. Secondary outcome was StU at 2 years and established by comparing allergic symptoms and immunological changes. Results The year 1 StU rates (%) for the 100%- and 25%-dose groups were 26.9 vs. 20.0 (HE), 7.7 vs. 15.4 (CM), and 50.0 vs. 16.7 (wheat), respectively. The year 2 StU rates were 30.8 vs. 36.0 (HE), 7.7 vs. 23.1 (CM), and 58.3 vs. 58.3 (wheat), respectively. There were no statistically significant differences in StU between years 1 and 2. The total allergic symptom rate in the 25%-dose group was lower than that in the 100%-dose group for egg, milk, and wheat. Antigen-specific IgE levels for egg-white, milk, and wheat decreased at 12 months. Conclusions Reduced maintenance dose of egg OIT showed similar therapeutic efficacy to the target dose. However, we were not able to clearly demonstrate the efficacy, particularly for milk and wheat. Reducing the maintenance dose for eggs, milk, and wheat may effectively lower the symptoms associated with their consumption compared to the target OIT dose. Furthermore, aggressive reduction of the maintenance dose might be important for milk and wheat, compared to the 25%-dose OIT

A Pinching Strategy for Fabrics Using Wiping Deformation

This paper discusses a strategy by which a robotic hand can use the physical properties of a fabric to pinch the fabric. Pinching may be accomplished by using a wiping motion, during which the movement and deformation of a deformable object occur simultaneously. The wiping motion differs from the displacement of a deformable object. During the wiping motion, there is contact, but no relative movement, between the manipulator and the object, whereas, during displacement, there is both contact and relative movement between the object and the floor. This paper first describes wiping motion and distinguishes wiping slide from wiping deformation by displacement of the internal points of an object. Wiping motion is also shown to be an extended scheme of pushing and sliding of rigid objects. Our strategy for pinching a fabric is accomplished with a combination of wiping deformation and residual deformation of the fabric under unloaded conditions. Using this strategy, a single-armed robotic hand can pinch both surfaces of the fabric without handover motion

Stochastic Static Analysis of Link Driven by Actuator Bundles

Abstract-This paper describes a stochastic static analysis of link angle driven by actuator bundles. We first demonstrate a movement of a link driven by actuator bundles in terms of high driving force. The variation of actuator parameters influences the movement of this mechanism. We confirm the link may shift and twist because of the variation of actuator parameters. We then introduce stochastic analysis to investigate the link angle considering the variation of actuator parameters. In the result, the variation of the link angle converges to zero when the number of actuator is large enough. In addition, we reinforce the result through dynamic simulation considering the variation of the parameters of actuators

Generation mechanism of large later phases of the 2011 Tohoku-oki tsunami causing damages in Hakodate, Hokkaido, Japan

Abstract The 2011 Tohoku-oki earthquake generated a large tsunami that caused catastrophic damage along the Pacific coast of Japan. The major portion of the damage along the Pacific coast of Tohoku in Japan was mainly caused by the first few cycles of tsunami waves. However, the largest phase of the tsunami arriving surprisingly late in Hakodate in Hokkaido, Japan; that is, approximately 9 h after the origin time of the earthquake. It is important to understand the generation mechanism of this large later phase. The tsunami was numerically computed by solving both linear shallow water equations and non-linear shallow water equations with moving boundary conditions throughout the computational area. The later tsunami phases observed on southern Hokkaido can be much better explained by tsunami waveforms computed by solving the non-linear equations than by those computed by solving the linear equations. This suggests that the later tsunami waves arrived at the Hokkaido coast after propagating along the Pacific coast of the Tohoku region with repeated inundations far inland or reflecting from the coast of Tohoku after the inundation. The spectral analysis of the observed waveform at Hakodate tide gauge shows that the later tsunami that arrived between 7.5 and 9.5 h after the earthquake mainly contains a period of 45–50 min. The normal modes of Hakodate Bay were also computed to obtain the eigen periods, eigenfunctions, and spatial distribution of water heights. The computed tsunami height distributions near Hakodate and the fundamental mode of Hakodate Bay indicate that the large later phases are mainly caused by the resonance of the bay, which has a period of approximately 50 min. The results also indicate that the tsunami wave heights near the Hakodate port area, the most populated area in Hakodate, are the largest in the bay because of the resonance of the fundamental mode of the bay. The results of this study suggest that large future tsunamis might excite the fundamental mode of Hakodate Bay and cause large later phases near the Hakodate port