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Human-in-the-loop task involving soft contact has become common in robotic manipulation research, especially in tele-operation and robotic surgery. Soft contact in this task may include a soft-fingered robot hand gripping a rock, or robotic control of forceps to pick up a tissue sample. In these scenarios, operators normally struggle with controlling the gripping force of the remote robotic hand, so that the grasped object is neither dropped nor damaged. Information about slippage , especially incipient slippage (or preslide), occurring at the contact surface is not properly sensed by the operator through cutaneous tactile feedback. This study aimed to generate preslide sensation on human fingertip for enhancement of slip perception of soft objects. We hypothesized that use of a method that can reproduce localized slippage can enhance human perception of slippage based on our previous study of soft-based contact. We created a grounded slip haptic display device, which can efficiently assess partial slippage on a human fingertip efficiently using a bundle of pins under only one actuation. This letter focuses on the creation of the device, including its theoretical underpinnings and design process, as well as assessing its efficiency in enhancing skin stretching through static and dynamic simulations. The device can be utilized to assess the slide process of a human fingertip, perceiving how and when slippage occurs on the contact surface; and can act as a platform for studies on human tactile perception.

The paper reports the vibration characteristics assessment of grid panels which were furnished in the main structure of 50kg-class micro-satellite ``SOHLA-1''. Three different types of grid panels with dimensions of 141.1 × 423.0 × 10.0mm, triangle-grid-type panel, rectangle-grid-type panel and frame-type panel, were investigated to find their dynamics through impulse test. Vibration characteristics were also simulated by a FEM computer soft NASTRAN. Application of flame-retardant type magnesium alloy to the panel was made to confirm the structural effectiveness of magnesium alloy panel.

The paper reports design process of a space boom to be installed in a 50kg-class micro-satellite, tentatively called as SOHLA-1. The total mass of the boom is 483g, while the length of the boom is 416mm. A spring-string type pin-puller was proposed. Vibration test with a bread-board model (BBM) of the boom leaded to an engineering model (EM) of the boom accommodated with a two-pin type pin-puller. Vibration test with the boom EM suggested some modifications to be made for a proto-type model (PM) of the boom. Vibration test, deployment test and thermal test on the boom PM confirmed feasibility of the flight model (FM) of the boom.

Neutron reflectometry was applied for the characterization of machined roughness on iron surfaces, including a buried solid–solid contacting surface. The observed distribution of the reflected neutron beam could be explained using a structure factor estimated from the Fourier transform of the physical roughness measured by a contact-type roughness gauge, particularly in the case of a periodic surface structure. In the case of random roughness, the accumulation of beams specularly reflected from every small local region of the surface gave a better explanation of the broad distribution of the scattered beam, where each local region was assumed to be flat and differently inclined relative to the incident beam direction. When the surface was buried beneath another material, the width of the distribution of the reflected beam became slightly wider than that in air. Although neutron reflectometry for the characterization of surface roughness has various limitations, it is still an effective tool for nondestructively observing the surface roughness at a buried contacting surface.

Lipid analyses in the fatty liver of rats, which was induced by feeding an amino acid-imbalanced diet containing 8% casein supplemented with 0.3% dl-methionine, were performed. In this type of fatty liver, triglycerides were found to be remarkably increased, in comparison with cholesteryl esters, cholesterols, non-esterified fatty acids, phospholipids and glycolipids. In the fatty acid composition of each lipid, no significant difference for the imbalance group was observed, except for that of triglycerides.It is suggested from the results of treatment with Triton WR-1339 that the transport of triglyceride from the liver to the plasma is not inhibited at all in the imbalance group, and from the determination of fatty acid distribution after feeding a dietary coconut oil that the transport of triglyceride from the adipose tissue to the liver is not almost altered.

Most of CAD systems can treat free-form curves and surfaces in the mathematical formula called NURBS (Non Uniform Rational B-Spline). Some NC controllers can handle NC data written in NURBS interpolated formula by using G 06.2 code. The use of NURBS expression enables us to decrease the amount of NC data, to eliminate the error due to the linear interpolation and to get rid of rapid acceleration and deceleration. However, little CAM systems can create NURBS interpolated NC data for 5-axis controlled machine tools. Therefore, the paper deals with the development of the main processor of CAM system, which creates CL data expressed by six-dimensional Non-Uniform B-Spline curve. The main processor can generate the CL data directly from CAD modeling data, while considering the interference between a ball-end mill and a workpiece and keeping the designated tool posture as long as possible so that the machined surfaces can be smooth.