This paper proposes a design technique for state-feedback H_∞ control with transient response shaping. A “loose” eigenstructure assignment is proposed, in which closed-loop eigenvalues (poles) and eigenvectors are assigned in specified eigenvalue regions and eigenvector cones respectively. This regional eigenstructure assignment problem is reduced to a rank-one LMI (Linear Matrix Inequality) problem, and easily combined with H_∞ control by means of enhanced LMI characterization.

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The effect of preview feedforward action is investigated in terms of the H₂ performance. We first derive a basic result on H₂ preview compensation for stabilized control systems and clarify the relation between the preview time and the achievable performance. The result is applied for an H₂ full-information control problem and the preview control law is derived with the achievable performance. The feature of H₂ preview action is further illustrated with a numerical example.

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A stabilization method of a rotary crane via switching control has been proposed in this paper. If the boom motion of the crane is restricted to only rotation about the vertical axis, the dynamics of the crane load becomes a kind of nonholonomic systems. We have approximated the crane system by a two-mode system which is given by linearizing about two different equilibria. For one system, the energy control method is used to maintain a certain oscillation of the load. By switching the mode at a suitable timing, the sway in radial direction can be settled. The remaining sway in circumferential direction is stabilized by a linear feedback law. The effectiveness of the proposed method is shown by simulations and experiments.

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This paper provides a new point of view to the method of Masubuchi and Shimemura, which is useful for analysis and synthesis of uncertain control systems, and presents an improvement and an extension of the method. In particular, this paper shows some properties of a transformation used in this method and reformulates the transformation as a decomposition of a rational matrix function. Combination of this decomposition and a technique of matrix dilation clarifies how conservative the above method is and shows how this conservatism is attenuated. Furthermore, the proposed method is extended to a general parameter-dependent linear matrix inequality.

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In this paper, the model matching problem with pole and zero assignments based on state feedback is considered. In discrete-time systems, poles and zeros can be assigned by state feedback law using the 2-delay input control method. However, in continuous-time systems, it is well known that zeros cannot be assigned by state feedback law. Considering this situation, the model matching problem for multi-input continuous-time system is investigated. First, the control input channels are increased by using the dual observer. Then by using these increased input channels, the state feedback law is obtained to assign zeros to the desired locations while preserving the controllability of the closed loop system. On the other hand, pole assignment is achieved by state feedback via original input channels. Finally, in order to indicate the effectiveness of our proposed method, a design example of 3-mass spring system is given.

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This paper describes an application of the virtual reference feedback tuning (VRFT) method for multivariable process control. The VRFT method is a direct method which determines parameters of a feedback controller using a set of input and output data of a plant. Originally, the VRFT method is presented for a design of a single-input single-output control system. In this paper, the VRFT method is applied for a design of a multi-input multi-output system. Experimental test is carried out and test results show availability of the VRFT method.

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A type of two-degree-of-freedom optimal robust servosystems have been proposed in some previous works, where the internal model is effective only when there are modeling errors or disturbance inputs. In such systems, robustness depend on the gain which is designed in order to optimize the transient response to step reference input. Thus, the two-degree-of-freedom nature of these optimal robust servosystems cannot be determined in order to optimize feedforward characteristics and feedback characteristics independently.
In this paper, a type of optimal robust servosystem in which thses two characteristics can be determined independently is proposed. Furthermore, it is shown that the proposed system is superior under a certain condition.

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Transporter routing design problem is important so as to design efficient Automated Guided Vehicle (AGV) systems. In this paper, we propose an effective transporter routing for AGV systems. The transporter routing is parameterized in a planning cost, a perception width and an action prediction. Then we apply Genetic Algorithm (GA) to design those parameters for AGV systems. The effect of our method is verified through simulations. The result shows that the number of the transported items increases by 24 parcent with our method.

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This paper proposes a new model of the membrane potential change of Paramecium for environmental stimuli. The proposed model calculates not only the membrane potential based on the Hodgkin-Huxley equation, but also the internal Ca²⁺ concentration in cilia that cannot be measured with the actual organism. This will be helpful to reproduce the behavior of Paramecium based on the mechanism of the actual organism. Simulation experiments demonstrate that the proposed computer model can reproduce the characteristics of the actual organism.

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In this paper we propose a revised DEMATEL (DEcision MAking Trial and Evaluation Laboratory), called stochastic DEMATEL, to extract structural model of a complex problematique and to represent the priority of each factor taking into account the uncertainty of structure. In the stochastic DEMATEL, the uncertainty of structure is expressed as a stochastic model. In addition, we expand composite importance into stochastic composite importance, which is the measure to decide the priority of each factor under the uncertain condition. From numerical experiments, we confirm the effectiveness of stochastic DEMATEL and stochastic composite importance for the uncertain structure. We analyze the structure of uneasy factors, as it turned out, it is clear that stochastic DEMATEL and stochastic composite importance can represent the useful information in the case of extracting the features of structure and deciding the priorities of each factor.

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There are many deformable objects such as papers, clothes, and ropes in life space of a person. Robots need skills to manipulate deformable objects, in order to take active parts in such space. However, it is difficult for robots to manipulate deformable objects well and possibility of failure to operate deformable objects cannot be denied. Therefore theoretical framework of error recovery for deformable object manipulation is required. For error recovery system, it is necessary to abstract profitable data from deformable objects, which are hyper degrees of freedom structures. Thus in this paper, we propose the description method of the condition of rope using the topological model and knot theory. And, we also propose the recognition method to obtain the structure of rope from visual information when a robot manipulates a rope. The effectiveness of method is confirmed by the experiment.

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System identification has been performed by genetic algorithm (GA) based on experiment data, while the modeling of nonlinear system for automotive engines including electronic control throttle servo system has been carried out. In such complicated nonlinear engine control system, however, it is well known that the estimation of the parameters with good accuracy has been made difficult, since there are many unknown parameters in the analysis model. In this study, the intake system related to intake air flow rate and the another system related to engine speed are independently identified at the first step, and the finally, the total system identification which simultaneously satisfies both systems is made by converging analysis. Moreover, as a result of also carrying out identification experiment using, this technique in an actual engine control system, the effectiveness of this new technique was confirmed.

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In this research, to evaluate the effectiveness of walking support system "Walk-Mate" based as a Co-creation system, we applied this system to a hemiparetic stroke patient. We analyzed it from the temporal and kinematic viewpoints. The results revealed the improvement of symmetry between right and left legs and the gaining of walking function by the side of paralysis, suggesting the effectiveness of Walk-Mate system.

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