This paper proposes a pipelined adaptive FIR filter based on the least mean EE$'$ (LMEE$'$) algorithm whose convergence property for colored inputs is superior than that of the LMS algorithm. This architecture is based on equivalent transformation of the LMEE$'$ algorithm. This implementation gives a shorter length of the critical path than that of non-pipelined implementation and its output latency is 0. Simulation results show the convergence property of the proposed implementation is the same as that of the non-pipelined one.

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[in Japanese]

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MRI(Magnetic Resonance Imaging) device is medical equipment which has been used to obtain the cross-sectional image of the human body. An open-configuration MR system is introduced at Shiga University of Medical Science in order to conduct microwave coaguration therapy by using near-real-time MR images. MR systems generate a serious noise (about 105dBSPL). Hence, operators and other medical staff (ex. nurses and anesthesists) are exposed to the large MR noise for many hours and cannot communicate with each other. This is an elevated risk of the operation. We therefore attempt to implement an active noise control (ANC) system in order to reduce the MR noise. However, MRI device generates too intense magnetic field for dynamic acoustic equipment. To solve this problem, we have proposed a head-mounted ANC system using piezoelectric loud speakers and optical microphones. In this paper, the cancellation performance of the head-mounted ANC system is demonstrated through some experimental results in order to prove the availability of the system in magnetic field.

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[in Japanese]

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This paper is concerned with cooperative stabilization, where we try to find a physical system which can be stabilized by cooperation even if any single agent alone is not stabilizable. Specifically, we consider a set of inverted pendulums which is locally controlled by a PD controller as a physical system. After review of theoretical results on the cooperative stabilization we show that there exists an inverted pendulum with PD controller which can be stabilized by cooperation even if any single inverted pendulum alone is not stabilizable.

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[in Japanese]

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[in Japanese]

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This paper describes future vision of Air Traffic Control (ATC). International Civil Aviation Organization (ICAO) has created the Air Traffic Management (ATM) concept including ATC. ATM is the dynamic, integrated management of air traffic and airspace safely, economically and efficiently. International trend of future vision such as ICAO, USA, Europe, and Japan is shown. Main technological components of future ATC are discussed. 4-dimentional trajectory management is the key element of future ATC.

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The planetary surface and the moon surface are severe environment, especially the lunar polar region currently assumed as an a target point has many unknown matters, such as geographical feature and environment, and there are many technical issues in landing and survey activities. The mobility and control of driving at a mountainous terrain has been the main issue of survey missions by the exploration rover. In this paper, technical issues for navigation and control of lunar and planetary exploration vehicles. And technical lissues for navigation and control of lunar surface mobility are also discussed.

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[in Japanese]

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Utilizations of compact chemical equipments and alternative energy sources are considered to bring about safe, energy-efficient and environment-friendly sustainable processes. In the present paper, we introduce application of ultrasound to polymerization process. Sensing technology and process control, which will be desired in future, are discussed from the viewpoint of efficient methods of operating properties of final product.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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This paper describes a predictive control method for boost DC-DC converters. The conventional predictive control relies on recursive computation and is time-consuming, so it can not be applied directly to switching power supplies such as DC-DC converters. In this paper, we propose a new and analytic predictive control algorithm for boost DC-DC converters. Compared with buck DC-DC converters, the boost convert has a quite different dynamic property. In particular, the undershoot phenomenon poses an obstacle to predictive control over a short horizon. This issue is discussed in detail and a suitable control index is proposed based on this discussion. This algorithm can be implemented on-line. Numerical simulations show that the proposed algorith outperforms the well-known PID-PWM.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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In this paper, we discuss grasping method for considering softness of the object for multi-fingered robot hands. Though the grasp of the soft (deformed) object in general are complex and difficult, we consider it applying the grasping method of Compensation Force and Binding Force. We also propose Mass-Spring-Damper Lattice as a soft (deformed) object to polish the grasping method.

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In the field of vibration control, the acceleration sensor is widely used as a vibration sensor for large-scale structure and soft ground. It is preferable to be able to use the velocity and displacement additionally. Then, the absolute velocity and displacement sensors are proposed, and they can be used as FB sensors. Up to now, the research, which is about each signals' FB to an air type anti-vibration apparatus with one degree-of-freedom using an absolute displacement sensor, has been experimented. Comparing to this research, the apparatus with two degrees-of-freedom will be controlled, and the applications of the absolute displacement sensors are verified in this paper.

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[in Japanese]

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[in Japanese]

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This paper deals with sliding mode control for trajectory generation to reduce the vibration of a robot arm. When the robot arm is driven, it produces its vibrations when its rigidity is low, so the prevention of such vibration has become more important. In this paper, in order to suppress a vibration of a robot arm, we propose a new control approach which generates a reference trajectory to the lower controller to suppress vibration. The effectiveness of the method is demonstrated by simulation studies.

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The objective of this study is to propose and provide various new tool-shaped interaction devices which are widely used in spatial interactive art and entertainment, facilitate interactive operation, improve the value of media contents, and fuel the spark of imagination of artists.

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This paper presents a new approach for synthesizing dance performance matched to input music, based on the emotional aspects of dance performance. Our analysis method extracts motion rhythm and intensity from motion capture data and musical rhythm, structure, and intensity from musical signals. For synthesizing dance per- formance, we ?rst ?nd candidates of motion segment sets whose features are matched to those of music segments, and then we ?nd the motion segment set whose intensity is matched to that of music segments. The experimental results indicate that our method actually creates dance performance as if a character was listening to the music.

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[in Japanese]

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In this paper, we propose a finger contact and force direction simultaneous recognition method based on image analysis, which can be applied to any kind of real surfaces. In this method, the fingertip contact is recognized by using the property that the color pattern of its nail changes from pink to white when it touches a surface. This method does not disturb user's tactile feeling and not limit the range where a contact recognition is possible.

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[in Japanese]

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According to the advancement of computer technologies, new musical expressions with motion enabled musical instruments have attracted a great deal of attention. These instruments enable users to generate and control sound by physical motion. Although a lot of researches and art performances have realized such characteristics, they do not fulfill the requirement of players to keep the procedure of whole performance under their control. We propose a new dance performance system that enables dancers to play music by dancing. We also propose new recognition techniques specialized to the adjustment in recognition timing of movement. The key techniques of the proposed method are (1) adaptive decision of the size of recognition window to recognize a motion in sync with BGM, and (2) motion recognition in two-phase (rough and detailed) to fulfill the accuracy in high speed recognition. Evaluation results confirmed that our proposed techniques improved the accuracy and quickness of recognition.

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[in Japanese]

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In this study, we propose a technique to detect fingertip's 3D position in any lighting environments with our proposed device. The device is composed of an omni-directional camera and LEDs. Our proposed method computes the distance to the fingertip based on irradiance of the LED light reflected off of the fingertip. Finally, we experimentally verify effectiveness of the technique.

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This paper describes an omni-directional video telepresence system that present undistorted images using GPU. Conventional telepresence systems use spherical mesh and cylindrical mesh. The systems calculate corresponding points to just vertices of the mesh. Therefore, users often see significant distorted image. The proposed system calculates corresponding points to whole pixels on presented image using GPU. Therefore, the proposed system runs in video-frame, the CPU load is low, and the presented images are undistorted.

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We propose a novel wearable imaging system that can capture omnidirectional movies from the viewpoint of the camera wearer. The imaging system solves the problems of resolution uniformity and gaze matching that conventional approaches do not consider. We combine cameras with curved mirrors that control the projection of the imaging system to produce uniform resolution. Use of the mirrors also enables the viewpoint to be moved closer to that of the camera wearer, thus reducing gaze mismatching. The optics, including the curved mirror, have been designed to form an objective projection. The capability of the designed optics is evaluated with respect to resolution, aberration, and gaze matching. We have developed a prototype based on the designed optics to capture various scenes from first-person perspective.

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In recent years, security camera systems have been installed in various public facilities. It is needed to implement more intelligent processes as tracking persons for image sequences of security camera systems. In this paper, we propose a face tracking and recognition method based on a Bayesian framework. We assume that an observed space is three-dimensional space, and we estimate a 3D position of a person. We use facial 3D shape, movement, and texture models for face tracking and recognition. An omnidirectional image sensors are used to acquire image sequences of a walking person because the sensors has wide views and are profitable for object tracking. Our system generates 3D positional hypotheses based on the facial movement model and these positional hypotheses are projected onto an image plane. Image features are extracted around projected hypotheses and the system distinguishes face using the image features. As results of evaluation experiments, we show that our proposed method is effective or face tracking and the tracking accuracy is improved in proportional to the number of cameras.

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Data fusion which uses observations from networked plural sensor and generates an integrated track achieves wide surveillance area and high accuracy by minimizing error ellipse based on error covariance matrix. However, a big premise of data fusion is that sensor bias error is zero. Therefore, it is assumed that fusion center may distinguish targets from sensors due to the bias error of observations from plural sensor, even if sensors observe a same target respectively. In this paper, we proposed a new bias error estimation algorithm which was based on kalman filter bias error estimator with grid search method. It was named the KGBE method (Kalman filter with Grid search Bias error Estimator). As the result of the computer simulations, we can confirm that the proposed algorithm KGBE achieves higher bias error estimation accuracy than conventional algorithm.

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On ground stereo vision system is used for autonomous hovering of a quad-rotor Micro Aerial Vehicle (MAV). This kind of system has advantage to support embedded vision system for autonomous hovering and landing, since embedded system occasionally gives inaccurate distance calculation due to either vibration problem or unknown geometry of the landing target, which makes the hovering or landing process fails.

Object tracking based on weighted histogram Continously Adaptive Mean-Shift (CAMSHIFT) algorithm were used to track the MAV. The original CAMSHIFT algorithm is developed by Bradski in 1998 for face detection. However, this original CAMSHIFT algorithm fails in differentiating between the target and objects in the background that has intensity same or near to the target. A weighted histogram CAMSHIFT applies a weighting algorithm which is 1) k(r) = 1-r for pixels near to center of target (r<=1) and 2) 0 for pixels that are far from center of target (r>1). Where r is the distance of a pixel to center of target expressed by

r = {2*(x-c_x)/(w_s-1)}² + {2*(y-c_y)/(h_s-1)}² ,

where x, y, c_x, c_y, w_s, h_s are x coordinate in the image, y coordinate in the image, x center coordinate of target, y center coordinate of target, image width and image height, respectively. By applying this weighted histogram CAMSHIFT algorithm, the objects in the background that has intensity values near or same as target can be differentiated.

Stereo vision system used in this research is Bumblebee from Point Grey Research that comes with a function for constructing a disparity image obtained from both, right and left camera. This disparity image contains information about a slightly difference between an object position in left and right camera. By using this difference and applying a triangulation method, target position (X, Y, Z) from camera can be derived.

A linear model for quad-rotor MAV is developed based on the system identification method. Quad-rotor MAV is a small size (40cm in diameter) of helicopter with 4 rotors. The movement of quad-rotor is based on the rotational speed of each rotor.

Next, a Kalman filter based Linear Quadratic Integral (LQI) is used for controlling the MAV. The position information obtained from image processing is sent to this controller for autonomous hovering purpose.

The experimental result shows that the weighted histogram CAMSHIFT based tracking process shows a good result. Additionaly, experiment on autonomous hovering also gives a good performance.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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We propose an estimation method of the transition time of hybrid systems in piecewise linear (PWL) form by using wavelet analysis. If each transition time is known, the continuous dynamics between adjacent discrete transitions will be identified by conventional identification method for continuous systems.
First, detectability of the discrete transition is defined. Under the assumption of the detectability of the discrete transition, an output signal is represented by using Taylor expansion around the transition time. In addition, the characteristic patterns in the wavelet transform of an output signal are analyzed. An estimation method of the transition time based on the analyzed pattern is proposed. Finally, the effectiveness of the proposed method is illustrated by numerical examples.

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The design of an ideal differentiator is a difficult and a challenging task. In this paper, we propose two types of differentiators to estimate the time-derivative of an output signal. To begin with, a velocity estimator is proposed based on the adaptive identification method and compared with the exact differentiator proposed by Levant. Then, an acceleration estimator is proposed with the non-passifiable adaptive schemes. Finally, the proposed differentiators are applied to the estimation of the speed and acceleration of the mass-spring system with a nonlinear dynamic friction force. The simulation results show that the proposed differentiators are robust to additive noises.

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To estimate the corporate default probability, it is important how we calculate the volatility indicates fluctuation of stock price. This research aims to more accurate default probability estimation using a volatility estimation model, which is expressly formulated fluctuation of volatility, by means of maximum likelihood procedure.

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[in Japanese]

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The steering feel of electric power steering might deteriorate by the change of viscous friction with the secular change or the temperature change. For this reason, we consider that it is possible to improve the steering feel if the viscous friction can be identified online during driving and the controller gains can be retuned on the basis of the identified value of the viscous friction. In this paper, we propose an on-line identification method of viscous friction and verify the effectiveness by using random steering operation to the EPS test bench.

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The objective in this study is to construct the model of a chechweigher with an electromagnetic force balance system. The model can be approximated by the combined spring-mass-damper systems and the equations of motion are derived. Finally, the validity of the proposed model can be confirmed by comparison of the simulation results with the realistic responses.

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