A novel way of actuating Shape Memory Alloy (SMA) is reported in this paper. Though conventional SMA actuation can get only one deformation pattern because of using whole heating like Joule heating, proposal method achieves various deformation patterns. Laser irradiation can heat any local area on SMA and deform only the heated area. And controlling this heated area size (by changing Laser irradiation parameter(s)) provides multiple transformation patterns. This increases SMA actuator degree of freedom and expands its application range. This report shows the temperature distribution on SMA foil heated by laser beam. The temperature extends radially from the irradiation center. Transformation area (over 50 degrees Celsius which represents transformation temperature) expands as the laser irradiation power increases, and does not depend on laser irradiation spot diameter. To demonstrate local transformation rectangle SMA foil memorized roll shape was used in this paper. The foil keeps flat shape by external tension and making protrusion(s) when a laser beam(s) is/are irradiated, and the transformation needs 2 seconds in average. This protrusion can be made at any locations (minimum space is 9mm between two protrusions). Protrusion size is controlled by laser irradiation power and external tension.

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This paper describes the dynamic behavior of feed drive systems at quadrant changes in circular motion, and then discuss about the generation model of quadrant glitches, which are often seen on the circular trajectories of NC machine tools. In this paper, the velocity and acceleration of the axis under circular interpolation motion were precisely measured by means of linear scales and servo-accelerometers, respectively. The velocity and acceleration at quadrant changes are simulated by a dynamic model which has two degrees of freedom. In addition, a friction model is newly proposed by considering the non-linear characteristics of friction force. From the experimental and simulation results, it is found that the proposed model well expresses the dynamic behavior of the axes, and that any axis does not stay at zero velocity when the motion direction changes. The Influence of the inertia of the feed drive mechanisms on quadrant glitches is also discussed through simulation results.

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The property of bending deformation in a laser forming of magnesium alloy plate has been investigated in the previous work. In this continued study, an effect of laser spot diameter on bending deformation behavior was studied in order to examine a feasibility of control of the bending direction and angle. The experiments of CO₂ laser forming of magnesium alloy plate were carried out under the machining conditions with a various laser spot diameter by changing the focal point of laser. In principle, the metal plate bends toward the laser head except for a very thin plate when the focal point of laser is on the work surface. In the experimental results, it was found that the bending angle decreased with an increase in the laser spot diameter and the plate continued to bend toward the opposite direction of the laser head when the laser spot exceeded a certain diameter. In this case, the plate bends toward the opposite direction of the laser head with a larger angle during the cooling period than a bending angle to the laser head side during the heating period.

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Using a binder-less PcBN tool, the influences of cutting speed on tool life and wear pattern in turning of Ti-6Al-2Nb-1Ta, which was a vanadium free titanium alloy for a surgical implant material, were investigated. In the condition of feed rate of 0.15mm/rev and depth of cut of 0.5mm with an application of a high pressure coolant, the tool life at cutting speed of 4.2m/s was the longest in the various cutting speeds. In conditions of cutting speed of below 4.2m/s the tool life was determined by chipping and flaking occurring on tool face, on the other hand, smooth wear on the tool face were observed in over 4.2m/s. And, it was confirmed that the smooth wear on the tool face in turning process appeared over 730°C of tool flank temperature , and the promotion of tool wear was so dependent on the cutting temperature. Also, in order to investigate this reaction in the cutting process, the experimental model reaction test between the tool material and the workpiece one by using the SPS equipment were conducted in addition to element analysis of the adhesive on the cutting edge using EDS and XRD. As a result, it was clarified that TiB2 was generated in the interface between the binder-less PcBN and the titanium alloy, and the reaction was sensitive to its temperature.

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Control strategies of cutting forces in end milling process have been long studied as a methodology to autonomously optimize cutting conditions. In particular, a model-based feedforward control approach has been recognized as a simple, and yet practical way to regulate the cutting force. This paper proposes an identification scheme of a prediction model of cutting force, and a feedrate control scheme based on it. Model identification cycles are included within a canned milling cycle, where the cutting force is estimated from servo motor current and spindle motor current in order to identify the cutting force prediction model. By performing cutting force control in subsequent processes based on the identified model, it is experimentally validated that the machining efficiency is significantly improved, while avoiding an excessive tool load.

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In this paper, we propose a new geometrical estimation method of sculptured workpiece surface for accurate cutting force prediction. In conventional methods of cutting force prediction, accurate representation of workpiece shape is required in order to calculate undeformed chip thickness at each tool position and tool rotation angle. However, workpiece in finish machining usually has complicated shape. So, it is difficult to realize workpiece shape estimation with sufficient accuracy in a short time. Then, we introduce an approximate model of instantaneous cutting force prediction and propose a new geometrical estimation method for undeformed chip thickness. At first, we introduce an estimation method of undeformed chip thickness based on the interference between sculptured workpiece and finite flutes on cutting edges. Then, we propose new concept of implicit representation for workpiece shape. It is based on the idea of tool swept volume. Next, we illustrate a new algorithm, which can realize effectively cutting force prediction. Finally, we developed a prototype system of cutting force prediction in order to evaluate the proposed methods. Then, we show the experimental results and conclusions.

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Monocrystalline silicon is the most important material for semiconductor industry, and is also widely used as a component material of the semiconductor manufacturing equipment which needs the precision machining. However the high performance machining technology without micro cracks for brittle materials has not yet been established. Especially the high aspect ratio drilling less than 1 mm in diameter is very difficult. Therefore, the new drilling method of monocrystalline silicon was introduced in this paper. The experimental analysis made it clear that the mirror finished surface without micro cracks was obtained by using the monocrystalline diamond drill, while many micro cracks were generated in the case of sintered diamond drill. Furthermore, the removal rate and the tool life were enough for high performance drilling.

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This paper proposes the soft structural microrobot which acts at narrow place in the fluid. The robot is operated on swimming, hopping and jumping. The body is made of NB and silicone rubbers. The actuator is a current driving type coiled shape memory alloy (SMA). The SMA expands and contracts by on-off current control for realization of the large and quick motion. The body is 30mm cube and 19mN weight. We obtained the swimming velocity 71.6mm/s, 2.25 times of the natural law and the height of jump 35mm, 1.2 times of the body length. The principle of swimming was realized not only fan motion of the bell but also jet propulsion.in quickly repetitive motion. Coefficients of resistance were determined for system identification of the theoretical model by convergent computation. The values take about 2 over the wide range of the duration of power stroke near driving condition of the maximum swimming velocity or hopping height, respectively.

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In this paper, an algorithm for projecting the machining remained area in a prior machining to the cutter location surface for the next machining is proposed. This projection is useful for automating some process planning task of mold machining, such as the determination of the milling region in the following machining operations. In our proposed algorithm, the milling simulation and the inverse offsetting of the result shape of the simulation is required. Most milling simulation programs use discrete Z-map models for representing the workpiece shape. In this paper, an algorithm for inverse offsetting the Z-map model is discussed. Our algorithm computes dense zig-zag curves covering the Z-map model, then it generates the swept volume of the inversed cutter moving along the curves to obtain their Minkowski sum shape. Proposed algorithm is implemented and an experimental process planning assistance program using this technology is demonstrated.

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A simulator for training manual arc welding operation by means of mixed reality technique was proposed and discussed in the previous paper. According to the experimental training results with the simulator in it, most trainees could not gain the skill of electrode tip positioning so well, though they could gain the skill of moving speed and angle control of the electrode. In this research, the authors investigate the reason for the less effectiveness and the solutions. As the results, it is found that in the conventional system, the trainees have difficulty in perception of electrode tip position, because of its inaccurate drawing in the real environmental image and two dimensional visual displaying. To improve the drawing accuracy, the camera for video-see-through HMD is replaced with high resolution ones and the multimarker position detection system is adopted. In addition, a stereo vision HMD with an easy vergence angle adjustment function is adopted to give the trainees three dimensional image. The experiments with the improved simulator show apparent reduction of the position-perception error of electrode tip and effective training.

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In a past thesis, we proposed a homogeneous parameter, homogeneous geometric Newton-Raphson method for dealing with a rational polynomial curve and we concluded that the algorithm is robust and locally unique. After more experiments, we noticed that we have to get over not only divergence but also oscillation problems.
Oscillation happens only when the equation has complex roots. So we propose a new geometric Newton-Raphson method, which can cope with complex root solutions. The algorithm has the features that the conventional homogeneous parameter, homogeneous Newton-Raphson method has and further more can find complex roots. The results of our experiments show that the algorithm is robust with respect to both divergence and oscillation, and also has local uniqueness property.

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To remove unwanted pigments in the skin laser light is irradiated on the pigmented lesion. Melanin, locally existing in skin, selectively absorbs the laser light. At present, the laser guns used in dermatology are manually operated and their laser spots are as large as 3 to 7 mm in diameter. It is thought that normal tissues, which don't contain melanin so much, are hardly damaged by the laser irradiation. But in reality, terrible burns appear after laser irradiation even in the normal tissue. We have developed a new type of laser apparatus for removing pigmented lesions with laser focusing and laser scanning technology. The fΘlens unit assembled by a shrink fitter can focus the laser beam well over a wide scanning width. Thus, the intensity of the focused laser beam became high enough even with a low-power laser oscillator. The focused laser irradiation lead also to another advantage. The cooling rate of the lesion, whose temperature rises over a given point by the focused laser beam, was increased. The effect of the focused laser irradiation on the pigmentation therapy was experimentally examined with the developed apparatus.

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Since 1981, the cancer has occupied the first cause of Japanese death. Therefore, it is an urgent matter to tackle the cancer problem. Recently, it is understood that outcome of the cancer disease in a prognosis is related to the special combination of genes. However, it is very difficult to predict the outcome of the cancer disease in a prognosis, because a huge number of genes exist and we have to explore the special combination of genes among them. This study aims at finding the special genes combination, which affects on the outcome of the cancer disease in a prognosis. Self-Organizing Maps (SOM) is applied to accomplish our aim. Namely, SOM is used to cluster genes to predict the outcome of the cancer disease. Two analysis methods are also introduced into the SOM results, because it is insufficient for SOM only to specify the combination of genes, which affects on outcome of the cancer disease. Numerical experiments present some useful information on the outcome of the cancer disease in a prognosis.

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Realization of resource circulation systems is recently desired. Thus this research aims to investigate conditions required to realize sustainable circulation systems, by means of making a product circulation model and applying life cycle simulation. A feature of this research is that a resource circulation system is modeled as interaction between agents with behavioral preferences. These agents include users and product makers in this model. Each user individually purchases products and each product maker individually supplies products. These actions are carried out through a market. Then some simulation scenarios were set up. These scenarios differ in behavioral preferences of product makers. Next, life cycle simulation was carried out in each scenario. As a result, the sale amount of products and environmental load in whole product life cycle were output. By means of comparing these results, it was possible to show the rational product development plan of product makers.

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In this paper, the measurement of cutting temperature associated with the bone cutting robot have been investigated for cortical bone. The temperature distribution on cutting edge just after finishing of the cutting was observed by a thermography near the cutting area, and the internal thermal distribution was also measured using the thermocouple buried near surface of the workpiece. The experimental results are summarized measured as follows. (1)The cutting temperature in up-cutting was higher than that in down-cutting. (2)When the cutting speed was increased from 7.85 m/min to 62.8 m/min, the cutting temperature was risen by about 10 deg.C, although the cutting force was not almost changed. (3)The cutting temperature could be lowered to about 30 deg.C using the cooled tool and bone at -5 deg.C. (4)As the result, it is suggested that the necrosis of bone tissue and cell would be avoided under this lowered cutting temperature.

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