A virtual elastic robot is proposed which has a body with multiple degrees of freedom. It is capable of fitting its body to the given surrounding environment. The intended robot is modeled by rigid objects connected by spring joints in a circular structure. Its control system manipulates spring actuators to realize elastic movements. This paper aims to acquire its control system for the robot to behave autonomously to adapt to various circumstances. A physical simulation is done to achieve given tasks for the elastic robot. The simulation result shows that the elastic robot achieve a simple locomotion task. Moreover, we conduct a learning experiment to adapt the robot to a complicated circumstance, in which an obstacle is placed. In order to allow the robot to adapt to there, we propose a composite behavior which consists of simple behaviors. The simulation results in forming a behavioral pattern of autonomous locomotion.

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This paper proposes a depth estimation method in order to achieve automation for micro-operation with a system consisting of an optical microscope and a micro-manipulator. The proposed method is able to estimate a distance of depth using difference between the blur widths of a micro-manipulator and a micro-object. The estimation equation is derived from a curve to which the equation based on the depth of field is approximated. The constants of the curve can be obtained by using the least-square method. In the experiments, the micro-operation system has achieved to automatically move the micro-manipulator to the depth position of a target object. It means that the estimation equation can precisely calculate distance of the target. In this paper, effectiveness of the proposed method is shown by these experimental results.

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We developed a mobile robot system equipped with a camera and an identification mark that it was possible for a position measurement by the stereo-camera method when a viewpoint changed freely. It is necessary to get distance between cameras and the relative posture of the camera precisely for the stereo-camera method measurement. The robot following a human being is easy to be affected by the obstacle to watch a human being indoors. Therefore the system of this study was able to expand the position measurement range by the stereo-camera method. In this report, we evaluated position measurement precision by this measurement method.

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A novel stereo robot vision system using a two-layer liquid crystal display ( LCD ) is proposed. The images of an object captured by right and left CCD cameras mounted on the robot are displayed on the two-layer LCD. The light intensity transmitted through the LCD depends on the degree of matching, i.e., parallax, between the images of two cameras. Therefore, the distance from the cameras to the object can be deduced from the intensity of the transmitted light without using a sophisticated computer algorithm. An example of the application of this stereo robot vision system for the automated chasing by an autonomous robot is presented. According to the distance between the camera-mounting autonomous robot and an object ahead, the autonomous robot advances, stops, or retreats to maintain a proper interval between the object. In this paper, the ability for real time processing of the autonomous vehicle is shown by the experiments.

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Vertical-scanning shape-measurement interferometry using white light cannot be used under vertically vibrating environment. Because, it is required to repeat predefined-length vertical movement with nanometer accuracy and interferogram capturing just after the movement. We developed the technology which can measure the changes of optical path difference (OPD) of an interferometer with nanometer resolution at around 20-μs interval. So, the technology can trigger interferogram capturing at even the moment when predefined-length movement happens to complete at an abnormal timing due to external vibrations. But vibrations in exposure time would change interferogram intensity captured. This change results in non-negligible measurement errors. Then we develop new phase extraction method which utilize history of OPD change in the exposure time and can remove the above errors. Validity of this method is also estimated by computer simulations.

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A special coolant system, named ‘Ion-shot coolant system’, was developed. The system uses an electrolyzed ELID coolant containing nano carbon particles. The products of the electrolysis of the ELID coolant and the added carbon particles in the coolant were effective on cutting of ferrous materials by diamond tools. A series of experimental studies has been conducted to understand the effects of the electrolyzed ELID coolant containing nano carbon additives. The coolants containing products of the cathode and anode were compared for micro cutting. The proposed method is expected to expand the use of diamond tools for ferrous materials aiming ultra precision machining of dies and molds with environment-friendly method.

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A dynamic analysis model of CMP process is developed by utilizing a finite element method in the present study. By considering relative motion of a wafer and a polishing pad in a steady-state process, a nonlinear equation of motion is derived based on Arbitrary Lagrangian-Eulerian (ALE) method in the proposed model. Since the dynamic CMP process in the steady-state can be treated as a static problem in an ALE coordinate system, computation time can be reduced significantly and meshing procedure can be simplified as compared with conventional dynamic structural analysis, i.e., time history response analysis. As a result, practical large scale problems can be solved accurately with consideration of the dynamic structural behavior. Two-dimensional structural analysis was carried out by applying the proposed model, and it was verified that the computation time can be reduced significantly as compared with the conventional analysis. Effects of viscosity of the polishing pad on polishing pressure distribution were examined, and it was clarified that stress concentration beneath the leading edge of the wafer greatly depends on the viscosity of the polishing pad, i.e., the consideration of dynamic viscoelastic behavior of the polishing pad is important to predict the polishing pressure distribution. The proposed model was subsequently applied to three-dimensional analysis of CMP process, and reasonable polishing pressure distribution, which was similar to that in the two-dimensional analysis, was derived successfully.

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Chips are generally assisted to curl and then broken into pieces by chip breakers. This conventional concept sometimes fails especially when the workpiece is highly ductile or the chip is thin and flexible. Contrary to this conventional method, a new concept of continuous chip disposal is proposed in the present research, where the chip is controlled not to curl and guided to a chip disposer. The key to this concept is chip control to suppress the curl and to guide the chip to desired direction. The continuous chip disposal can also be combined easily with chip-pulling cutting. It is known that the cutting process is improved drastically by pulling the chip, i.e. cutting force, energy and heat are all reduced remarkably. Therefore, new chip control methods are developed as basic technologies to realize the continuous disposal and the chip-pulling. A chip control method is proposed to suppress the up-curl by convex tool geometry, i.e. curved rake face with inverse curvature to the up-curl. Tools with the inversely curved rake faces are developed, and it is confirmed that the up-curl can be suppressed at a certain inverse curvature. Another chip control method is proposed to suppress the side-curl and to control the chip flow direction at the same time by forming guide grooves on the rake face. The tools with the guide grooves and a guide tunnel are developed, and it is demonstrated that the chip can be guided successfully along the guide grooves into the guide tunnel over a fairly wide range of conditions.

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This paper proposes a design optimization method for disc brake systems that specifically aims to reduce brake squeal, with robustness against changes on contact surface pressure distribution, based on the concept of First Order Analysis. First, a simplified analysis model is constructed in which a pressure distribution parameter is introduced, and the relationships between the occurrence of brake squeal and the characteristics of various components is then clarified, using the simplified model. Next, a new design performance measure that takes pressure distribution changes over the contact surfaces into account is proposed for evaluating brake squeal performance, and an optimization problem is formulated in which this performance measure is used as a constraint condition, with maximization of the brake-pad contact area as the objective function. The optimization problem is solved using a genetic algorithm. The proposed method is then applied to design problems and a disc brake system is constructed based on an optimal solution. Finally, experimental studies are conducted to confirm that the proposed method can yield optimal designs that minimize brake squeal and are robust against pressure distribution changes.

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