A fingertip guiding manipulator for mental image creation of multi-stroke drawings

Authors developed an improved fingertip guiding manipulator that helps visually handicapped persons create mental images of relief sculptures. The manipulator has three functions: (1) an indicating function of knob-moving-direction by a stepping-motor attached at the arm end, (2) a fingertip traction function by a quadrilateral parallel link manipulator, and (3) a fingertip up-down motion function by a linear motion actuator. The former two functions are utilized to represent planer 2D figures, and the last one is to represent the relief sculpture representation together with the former two. Some preliminary experiments were carried out, and the human perceptual thresholds with the up-down motion and the fingertip rotation, and the human kinesthetic following performance were clarified. These thresholds shall be used as the back data for designing mechanical specifications of the proposed fingertip guiding manipulator.     

Path planning based on geographical features information for an autonomous mobile robot

We propose a path-planning algorithm for an autonomous mobile robot using geographical information, under the condition that the robot moves in an unknown environment. Images input by a camera at every sampling time are analyzed and geographical elements are recognized, and the geographical information is embedded in an environmental map. Then the path is updated by integrating the known information and the prediction on the unknown environment. We used a sensor fusion method to improve the mobile robot's dead-reckoning accuracy. The experimental results confirm the effectiveness of the proposed algorithm as the robot reached the goal successfully using the geographical information.     

Buckling assessment procedure for large diameter vessel with multiple local thin areas subjected to external moment

The procedures described in Ibaraki FFS rule (2006) based on the p-M (internal pressure ratio and external bending moment ratio) method (Konosu and Mukaimachi, 2006) were used to predict the plastic initiation condition and the collapse condition for cylinders with a local thin area (LTA) subjected to combined internal pressure and bending moment. The effective wall thickness, t*, for the buckling assessment on a vessel with an LTA was proposed for use instead of wall thickness based on approximation which simply took into account only the effect of section modulus reduction (Konosu and Mukaimachi, 2006). The buckling evaluation on a vessel with an LTA was presented by Mukaimachi and Konosu (2009) and that was shown to be easily and adequately conducted by applying t* to the well-known Donnell's or Miller's equation. In this paper, the attention was focused on the procedure for assessing the buckling of large D/t vessels with multiple aligned or non-aligned local thin areas. From the comparison with the results of non-linear FEA, a combination rule and a buckling assessment procedure for multiple LTAs (flaws) subjected to external moment are proposed. The interaction-affected area for multiple cracks can be applied as the combination rule to evaluate the buckling of a large diameter vessel with multiple flaws subjected to external moment. From the comparison between the buckling loads of FEA results and the conventional buckling equations using the measured yield stress, an additional safety factor ‘ks’ is proposed so as to maintain the margin of 1.5. When the specified minimum yield stress is applied to Donnell's or Miller's equations, the margin for the buckling load of a cylinder with multiple flaws is more than 2.08 and 2.29, respectively.     

Optical compensation of hologram distortion avoiding interpage crosstalk on reconstructed image in angle-multiplexed holograms

We are studying a form of holographic data storage with phase conjugation, and we compensated for hologram distortion due to shrinkage of photopolymer materials in the holographic medium by controlling the wavefront of the reference beam. When a high NA lens and narrow angle interval of angle multiplexing are employed to obtain a high data recording density, some wavefronts cause interpage crosstalk on the reconstructed image. We tried to determine the moving range of actuators in a deformable mirror for controlling the wavefront. As a result, we found that the distortion in the hologram could be compensated while avoiding interpage crosstalk and that the bit error rates of the reproduced data could be decreased. We also found that the optimized wavefront could compensate for distortions in several neighboring data pages. This method can ensure a high data recording density in holographic data storage.     

Novel dry-desulfurization process using Ca(OH)2/fly ash sorbent in a circulating fluidized bed

A dry-desulfurization process using Ca(OH)2/fly ash sorbent and a circulating fluidized bed (CFB) was developed. Its aim was to achieve high SO2 removal efficiency without humidification and production of CaSO4 as the main byproduct. The CaSO4 produced could be used to treat alkalized soil. An 83% SO2 removal rate was demonstrated, and a byproduct with a high CaSO4 content was produced through baghouse ash. These results indicated that this process could remove SO2 in flue gas with a high efficiency under dry conditions and simultaneously produce soil amendment. It was shown that NO and NO2 enhanced the SO2 removal rate markedly and that NO2 increased the amount of CaSO4 in the final product more than NO. These results confirmed that the significant effects of NO and NO2 on the SO2 removal rate were due to chain reactions that occurred under favorable conditions. The amount of baghouse ash produced increased as the reaction progressed, indicating that discharge of unreacted Ca(OH)2 from the reactor was suppressed. Hence, unreacted Ca(OH)2 had a long residence time in the CFB, resulting in a high SO2 removal rate. It was also found that 350 degrees C is the optimum reaction temperature for dry desulfurization in the range tested (320-380 degrees C).     

In-plane deformation observation of indentation along indenter surface

In this paper, the in-plane plastic deformation, which is perpendicular to the contacting load, of soft metal in contact with a hard spherical indenter is observed on a rolled aluminum surface. By measuring a displacement due to indentation of lattice points described on the aluminum surface, the in-plain deformation is obtained. Many small ferrous impurities are scattered on and in this aluminum specimen. When a hard spherical indenter is pressed onto this aluminum surface, the distance between impurities is changed by the surface plastic deformation. The change in distance between impurities is obtained using the image processing method, and it is demonstrated that the in-plane plastic deformation of surfaces caused by indentation can be observed. Results by both the lattice point method and the image processing method are compared quantitatively.     

Influence of Oxygen on the Kinetics of Omega and Alpha Phase Formation in Beta Ti–V

Metallurgical and Materials Transactions A - A detailed understanding of the kinetics of phase formation in $$\beta $$ -stabilised titanium is of decisive importance for the applicability of these...