Profiles and Activities : National University Corporation Fukushima University


Tadashi Ishihara(Professor)
Affiliated Specialty Division Division of Human Support System
Specialized Field of Study Control Theory and Its Applications 
Final Academic Background Graduate School of Tohoku University 
Academic Degree  Ph.D(Tohoku University)

Courses In Charge

Physics I
The lecture introduces the classical mechanics as a bssis for describing various phenomena in mathematics.
Electrical Circuits 
The lecture gives the introductory electrical network theory. It is emphasezed that electrical circuts ara dynamical systems described by differenctial equaations.
Intelligent Control
As a basis for developing intelligent control systems, the lecture introduces the classical control theory which requires the knowledge of the classical mechanics and electrical circuits.

Main Research

Duality of control signals
In general, control signal in a control system has the effect not only on the plant state but on the quality of the state estimation. This property is called duality of the control signal. In the framwwork of the stochastic optimal control theory, we discuss the control system design explicitly taking account of the property.
Extension of LQG/LTR method
LQG/LTR method is a well known classical design method for linear multi-variable systems. We have proposed a new method called the singular LQG/LTR method for disturbance cancellation control problems for which the conventional LQG/LTR method can not be applied. Currently, we investigate the extension of the proposed method to a wider class of the control system design problems.
Control systems design based on the principle of matching
It has been widely recognized that the control systems design methods based on the optimal control theory can not deal with multiple design specifications usually requaied in real design problems To over come the difficulty, Dr. Zakian in United Kingdom has proposed a new design method based on the principle of matching. In cooperation with the international group led by Dr.Zakian, we discuss the various fundamental issues of the new design method.

Introduction of Laboratory

My research field is control theory and its application in the area of control engineering. Control theory is fairly general research field that can be applied to airplanes, automobiles, robots and mechatronic systems. Since fruits of the theory are usually realized as software, their importance is rarely recognized in daily life. My main effort is put in the study of the control theory seeking new useful theoretical results. For application study, I believe that cooperation with other researchers and specialists is essential.

Recent Writings, etc.

1. M. A. Fard, T. Ishihara and H. Inooka, “Identification of the head-neck complex in response to the trunk horizontal vibration,” Biological Cybernetics,90,pp. 418-426, 2004.
2. T. Ishihara, H.-J. Guo and H. Takeda, “Integral controller design based on disturbance cancellation: Partial LTR approach for non-minimum phase plants,” Automatica, 41-12, pp,2083-2089, 2005.
3. T. K. Liu and T. Ishihara,”Multi-objective genetic algorithms for the method of inequalities,” Control Systems Design: A New Framework, Chapter Contribution, Springer, 2005.
4. M. Nankyo, T. Ishihara and H. Inooka, “Feedback control of brake system on railway vehicle considering nonlinear property and dead time,” J. Dynamic Systems, Measurement, and Control, Transactions of the ASME, 128-3, pp.244-250, 2006.
5. T. Ishihara and T. Ono, “Design of critical control systems for non-minimum phase plants via LTR technique,” IEEJ Trans. on Electronics, Information and Systems, 127-5, pp.733-740, 2007.
6. J. Wu, T. Ishihara and Q.M.J. Wu, “Davison type integral controllers for time delay plants using a simplified predictor,” Control and Intelligent Systems, 35-3, pp.244-253, 2007.