Michio Kono

Controllability and stabilizability of a networked control system with periodic communication constraints

Abstract This paper proposes a new model for a networked control system and considers its controllability and stabilizability. To control a linear time-invariant discrete-time plant via a bus with limited capacity, we introduce a hold device and a communication sequence which follows a given ω -periodic pattern. Incorporating the communication sequences and hold device into the original plant amounts to extending the original time-invariant state equation to a ω -periodic one which has the higher order. We assume that the communication sequence is admissible. It is shown that controllability and stabilizability of the plant are preserved in the periodic extended system under the assumption that the zeros of the communication sequence characteristic polynomial do not coincide with the eigenvalues of the plant.

Trajectory for saving energy of a direct-drive manipulator in throwing motion

In this article, equations of motion of a closed-type manipulator, whose mechanism can easily be made lighter, are derived in consideration of the characteristics of the driving source. Considering the final condition of angular displacement and angular velocity in throwing motion, trajectories of velocity for saving energy are calculated by iterative dynamic programming, and the dynamic characteristics of manipulator control based on the trajectory for saving energy are analyzed theoretically and investigated experimentally.

An LMI approach to observer-based guaranteed cost control

This article presents a design method for an observer-based guaranteed cost controller for a class of uncertain linear systems, in which full state variables cannot be measured. The perturbations are assumed to be described by structural uncertainties. The linear matrix inequality (LMI) approach is applied to design the observer-based controller. The controller and observer gains are obtained by solving the LMI optimization and feasibility problems, respectively. A numerical example shows the potential of the proposed method.

Stereo Correspondence Using Color Based on Competitive-cooperative Neural Networks

In the literature, most of the stereo matching methods have been limited to gray level images, only few authors have dealt with color images straightly. In this paper, we propose a novel area-based color stereo matching method based on competitive-cooperative neural networks. Seven kinds of color spaces are tested in order to evaluate their suitability to stereo matching. The experimental results show that the matching precision is increased efficiently, when using adaptive color features instead of gray values.According to the experimental results, Ohta, Opponent and YCbCr color spaces can offer good color features for stereo matching.

Robust control method for the inverted pendulum system with structured uncertainty caused by measurement error

In this article, we propose a design method for an inverted pendulum system with a structured uncertainty. We consider that such an uncertainty is caused by a measurement error in the rotation angle of the pendulum and effects on the system structure that cannot be included in the nominal elements. For the uncertain system obtained, we apply an integral tracking control and the guaranteed cost control to design a robust, stable, tracking control system. Finally, we show the effectiveness of our method through a numerical example.

A study of manipulator with passive revolute joint

In this article, equations of motion of a manipulator, whose mechanism has a passive revolute joint, are derived in consideration of the characteristics of driving source. Considering the fi nal condition of displacement and velocity of the passive joint, trajectories of velocity for energy saving are calculated by iterative dynamic programming. And the dynamic characteristics of manipulator control based on the trajectory for energy saving are analyzed theoretically and investigated experimentally.

Three-dimensional parallel Turing machines

Informally, the parallel Turing machine (PTM) proposed by Wiedermann is a set of identical usual sequential Turing machines (STMs) cooperating on two common tapes: storage tape and input tape. Moreover, STMs which represent the individual processors of a parallel computer can multiply themselves in the course of computation. On the other hand, during the past 25 years or so, automata on a three-dimensional tape have been proposed as computational models of three-dimensional pattern processing, and several properties of such automata have been obtained. We proposed a three-dimensional parallel Turing machine (3-PTM), and dealt with a hardware-bounded 3-PTM whose inputs are restricted to cubic ones. We believe that this machine is useful in measuring the parallel computational complexity of three-dimensional images. In this article, we continue the study of 3-PTM, whose inputs are restricted to cubic ones, and investigate some of its accepting powers.

A Novel Approach to the Identification of Exogenous Input of Stochastic Systems Using Pseudomeasurement

Abstract In this paper, a novel approach to identify an unknown parameter vector of the exogenous input to a class of stochastic linear systems is proposed. The key of the approach is to introduce an additional information about the unknown parameter vector which is called the pseudomeasurement. Augmenting this pseudomeasurement with the original observation data, the identification of unknown vector as well as the state estimation is performed. The efficacy of the proposed approach is confirmed by simulation studies.

Stabilization of linear time-invariant systems with periodic communication constraints by output sample hold control

This article considers feedback control systems wherein the control loops are closed through a real-time network, and expresses the linear time-invariant system with the constraint in an input or output as a periodic discrete time system. It is shown that this system is stabilized by using output sample hold contol. This method has the merit that the capacity of a sensor-controller communication bus is small.

Parallel Turing machines on four-dimensional input tapes

The parallel Turing machine (PTM) proposed by Wiedermann is a set of identical usual sequential Turing machines (STMs) cooperating on two common tapes: storage tape and input tape. On the other hand, due to the advances in many application areas such as motion picture processing, computer animation, virtual reality systems, and so forth, it has become increasingly apparent that the study of four-dimensional patterns is of crucial importance. Therefore, we think that the study of four-dimensional automata as a computational model of four-dimensional pattern processing is also meaningful. In this article, we propose a four-dimensional parallel Turing machine (4-PTM), and investigate some of its properties based on hardware complexity.