The basic motions of the slewing crane as construction machines are classified into cargo windup, boom derricking and boom slewing. The purposes of controlling the crane are to transfer the cargo to the target point as quickly as possible with suppressing the swaying and to quickly minimize the residual sway at the target point. At present, the crane operation depends on the skill and sense of the operator, so its automatic operation is desirable from the standpoint of economy and safety. Concerning the anti-sway control of a rotational crane, several methods are known; that based on an optimum reference pattern suppressing the swaying, that based on the feedback control system using a linear approximation around θ, and that based on θ=tan^-1F(x,y) proposed by authors. However, the first and the second methods are not effective for the disturbance such as a wind, and the third one is unstable when the denominator =0 of tan^-1F(x,y). So, we have developed the method based on the idea of the backstepping approach and have got remarkable effects.

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It is widely acknowledged that pursuing solely convenience causes such problems as excluding users, spoiling users ability, and so on. Inconvenient systems and methods provide users with such benefits as enhancing awareness and allowing creative contribution. However, the systematic way for implementing such benefits is now unknown. Focusing on the contradiction between convenience and such benefits, this paper introduces the contradiction matrix that is a method of TRIZ for inventive problem solving. By analyzing many inconvenient tools and methods, some principles, which relate inconvenience and their benefits, are derived and are placed in what we call fuben-eki (FUrther BENEfit of a Kind of Inconvenience) matrix. This paper demonstrates the way for utilizing the matrix, just like the contradiction matrix of TRIZ, for supporting idea generation of implementing benefits of inconvenience.

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In this article, we introduce a novel method of assisted driving system intended to help drivers to improve the reverse parking skill. The system is able to assist the driver by applying the haptic instruction on the steering wheel in order to prompt the driver to make the adequate operation. This is helpful to train the driving technique in an intuitive manner. To determine the assistance means, we conducted the preliminary experiment in order to investigate the quantitative characteristics of human driving. Afterwords, we developed 1/10 Scale Car Simulator as a simulation environment on which we installed the proposed assistance method. Finally, we conducted the experiment with subjects by using the simulator. In consequence, we validated that the proposed assisted driving system could accelerate the learning of the humans' driving skills.

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Ultrasonic vortex flowmeters are often applied, such as for semiconductor production equipments, since the significance of the fluid control with low-maintenance flow measurement is remarkably increasing in these days. However, it is difficult to measure the flow velocity of gas-liquid two-phase flows, which are associated also with the chemical and biomedical engineering, with the use of ultrasonic vortex flowmeters. To examine the character of the reflection of ultrasonic by the small gas bubbles, reflectivity of the ultrasonic signals in gas-liquid two-phase flows has been measured. As a result, we found that the character of the reflection of damped ultrasonic was determined by void fraction and dispersion of the bubble. On the other hand, the relation between the flow velocity and the vortex shedding frequency was independent on the presence of gas bubbles. This suggests that the auto gain control (AGC) to amplify the ultrasonic amplitude would be effective.

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Repetitive control is known as an effective way to achieve the tracking to periodic references. However in the case that the reference is determined synchronously with one of the state, for example, the speed of a racing car going around a circuit, mere tracking to a periodic function in time is not enough. To solve this problem, we consider a version of repetitive control with an event-triggered switching action. We show that the local stability of the corresponding closed-loop system is characterized by the spectral radius of an integral operator with initial conditions. the state transition operator. The result is verified with numerical simulations.

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Stepping motor has been widely used for both factory automation (FA) and office automation (OA), because it is able to achieve high-accuracy positioning by open loop control. This paper mainly presents the suppression control of residual vibration for the feeding part of chip taping machine. In this paper, a novel system that can perform high-speed movement and high-accuracy positioning while suppressing residual vibration is proposed, even if the load to a feeding part inhomogeneously varied when the stepping motor is driven intermittence.

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In this paper, we propose a data-driven method to update state feedback gains for linear time invariant systems. Particularly, by employing the concept of fictitious reference iterative tuning, we give an effective update method for a controller to be improved with more desired property. We also show that the proposed method can be performed by the least squares method. We illustrate an experimental example on control of the two-wheeled inverted pendulum to show the validity of the proposed method.

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This paper investigates the visual feedback control by the visual motion observer with input saturation. Firstly, using standard body-attached coordinate frames (the world frame, camera frame and object frame), we present the visual motion error system which consists of the estimation error system and the pose control error system. Next, we propose the control law with the input saturation. After that, stability analysis of the closed-loop system is discussed in the sense of Lyapunov. Although the proposed control law cannot be designed based on the passivity of the visual motion error system explicitly, the skew-symmetric property of the visual motion error system plays an important role in the stability analysis. Finally, experimental results are shown in order to confirm the proposed method by using AR.Drone as a small unmanned aerial vehicle.

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Power source and sensing of self position are commonly required for mobile robots. Recently, wireless power transmission and position sensing from the systems embedded in the surrounding space are proposed as effective measures. Since wireless power transmission and position sensing are regarded as totally different functions, they have been realized by independent systems. However, combining multi-function into a single system has various advantages such as cost down and space-saving. Therefore, in order to realize both functions in single system, the authors have researched on position sensor via magnetic resonance coupling which have been used in the wireless power transmission field. However, there were several problems in the prototype system using arrayed transmitter antenna such as, reduction of Q factor due to the increase of wire length, the compensation capacitance values have to be set individually and antenna alignment are fixed. Therefore, as a solution, position sensor using relay antennas via magnetic resonance coupling is proposed in this paper. The novel position sensing method is proposed and evaluated through the position sensing experiment assuming mobile robot as the target.

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In this paper, a new identification method for systems with a circulation structure is proposed. The output of the system is strongly correlated with that of the previous circulation period under the influence of the substances circulating in the system. Therefore, the model for such system contains higher order terms, which makes it difficult to identify the system when its circulation period is unknown. To deal with the systems with unknown circulation period, the proposed method utilizes the feature extraction method with l₁-norm optimization technique, which can estimate sparse parameter vector appears in the models with the circulation structure. A numerical simulation is given to show the effectiveness of the proposed method.

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Complex-valued network inversion solves inverse problems that include complex numbers. To solve the ill-posedness, we propose the regularization by providing target phases to complex inputs. The simulations of the inverse power function and the inverse kinematics are carried out.

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