This paper proposes a new type of self-bearing motor which uses Lorentz force with Halbach magnet. It is expected to have a good dynamic response and high levitation capability. For realizing high magnetic flux airgap, Halbach magnet is used for the rotor. First, the fundamental principle is introduced how the motor produces rotating torque and radial levitation force. Next, Halbach magnet is introduced and the motor is designed. However, the control forces for x and y directions are quite different and the levitation is unable. For the stable levitation two sets of three phase coils are used. The levitated rotating test is carried out successfully. The top speed of 4 410 rpm and the maximum motor efficiency of 72% are recoded.

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Active Magnetic Bearings (AMBs), which utilize magnetic levitation technology, have recently been applied to industrial rotors. The controller of AMBs is needed for stabilizing the instability of high order bending modes, which is called the spill over instability, because a rotor has many eigen modes. In this paper, the mode control and the design method of a digital controller are described. We propose to apply a new type of compensator, Phase Shifting Filter, instead of a Notch filter, which works well for the stabilization of the spillover instability. By using the phase shifting filter, we designed the AMB controller to provide the optimal damping against high order bending modes. The stability margin against the spillover instability is evaluated by using open loop transfer functions and sensitivity functions in numerical simulations and experiments. Finally, the rotational speed successfully passed the second bending critical speed during the rotational test by using this controller.

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The bias current in the magnetic is a fatal element in energy storage flywheel system for heat and rotational resistance. A bigger flywheel is used in the energy storage flywheel system for higher energy storage density. This lead to a strong gyroscopic effect. This paper verify a new method of design reduced-order model for mechanical system with strong gyroscopic effect which is proposed in one of our paper. The method used cholesky decomposition to construct the reduced-order model of mechanical system. In order to demonstrate the validity of this method, a 0.5 KWh class magnetic bearing system is designed based on the 10 MWh class energy storage flywheel system which used in this paper. The new zero bias magnetic bearing is used in the system. From the simulation and experiment, it had been verified that the proposed method is useful for control system design taking into account a strong gyroscopic effect.

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In this paper we propose a mobile mechanism using vibration. Our proposed mechanism consists of two small voice coil motors, several bundles of elastic fibers. These elastic fibers aslant attached to a body of the mobile mechanism change vibration into driving force using the difference of friction force, and elasticity. The apparent friction coefficient between elastic fibers and the surface of a wall changes with attachment angles. We measured moving velocity by changing attachment angle of elastic fibers and applied frequency. The experiment result showed that velocity of the mobile mechanism was controllable by input frequency. We controlled move direction by controlling two motors independently. We enabled control of the running direction by making two input waves produce phase difference.

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Seismic ties are the connecting devices installed between a boiler and its supporting structure in thermal power plants. The seismic ties are made of steel and allowed to be used in the elasto-plastic deformation region in order to reduce the seismic response of the boiler structure. This paper deals with an anti vibration performance proof test for an optimized stiffness distribution of elasto-plastic joint elements for boiler structures using a down-scaled boiler structure model on a large shaking table.

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In this paper, a new type of arm-type damper consisting of two links, two joints (universal joints with friction) and a hinge (a rotary oil damper) has been developed. The damper is able to suppress six modes of vibration of a machine, three in translational modes and three in rotational modes. The trial damper was made and the resisting force characteristics in the three translational directions were discussed theoretically and experimentally. The seismic responses of a three-degree-of-freedom system and the frequency response of a one-degree-of-freedom system, which consist of a mass and four coil springs and supported by the damper, were measured using a two-dimensional electro-hydraulic type shaking table. The experimental results are compared with the calculated ones, and the effects of vibration suppression of the damper are discussed.

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We make a semi-active shock absorber on an experimental basis and realize its intelligent control. In the shock absorber, an area of orifice is controllable widely according to the angle of the adjustment shaft which is rotated by a stepping motor. A load cell is only used as a sensor because of practically. We intend to control the high shock absorbing efficiencies of the shock absorber using intelligent control method in spite of rare detum. In the experimental studies, masses and energies of collision things are estimated from resisting force values by means of neural networks. Neuro-like fuzzy control using backpropagation leaning is applied to the shock absorber and high shock absorbing efficiencies are realized for various crushes.

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In order to analyze the tire noise emission during vehicle acceleration running, noise source detecting method with acoustical holography was applied to vehicle acceleration running condition, which was developed to constant speed running. This paper describes the effectiveness of 2-dimensional arrayed microphone method by simulated calculation and the experiments with model noise sources, and propose the new method to identify the noise source without valid information on noise source frequency, which is pure tone or broadband noise.

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This paper considers the fault diagnosis for vibrating systems. An estimation method of the mode shapes by using independent component analysis is presented. The harmonic signal, impulse signal, and white noise are available for the input signals. The method only requires independence of the modal coordinates, and it does not require the physical parameters of vibrating systems and the inputs' information. In the numerical example, fault diagnosis for a plate is presented as an application of the proposed method.

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Recently, much attention has been focused on application of teaching and learning algorithm such as radial basis function (RBF) networks. Since it is expected that visual recognition problem, especially expressional and obstacle recognition, the estimated results can be cope with their situated environments without human associations as possible. On the other hand, The conventional navigating system for satellite in space has been suffered from the problem of huge check sequence we needed as the complexity of task increases. In this paper, availability of on-line learning with RBF network is discussed to apply for the image recognition of the posuture in which micro satellite (i.e daughter ship) is approaching to the docking port of the mother ship. The ability for all-purpose of RBF is useful for uncertain inputs and the method for the image estimation in docking phase is established experimentally under the 6 DOF environment.

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In this paper, we derive a linear and a nonlinear model of helicopter autorotation maneuver focusing on main rotor revolution and decent rate dynamics. The nonlinear model for above dynamics is derived from Blade Element Theory combined with the induced velocity linear approximation proposed in this paper. The linear model is derived by implementing a neural network optimization method based on experimental data. The derived nonlinear and linear models are verified by comparing simulated data of the model with experimental one. Finally we carry out preliminary experiment of autorotation landing with a simple PI controller. Rotor revolution and decent rate are found to be well controlled by the designed controller.

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In the present study, the shape optimization of a golf club is investigated. The optimization of thickness distribution of a clubface is studied for maximizing the release velocity of the ball under the constraint of a constant amount of the clubhead weight. The basis vector method, which is an approximate method for the optimization problems, is employed because the sensitivity cannot be derived analytically. The basis vector represents the fundamental change of the shape, and it is preferable for obtaining effective results that the basis vectors are independent mutually. The eigen-modes are used to create the basis vectors in a 3-dimensional problem. The theory of impedance matching is comfirmed numerically by a 2-dimensional example. A 3-dimensional example is given to show that this approach is effective to optimal design of golf clubhead.

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Miniaturization of actuators for reducing robots weight has been mainly discussed as improvement motion velocity of robots. However, it only expects performance of actuators, so it is difficult to say contribution of robotics control technology. So we propose the techniques of intelligent motion control. It has key points that efficiently use robot's actuators and are optimization of actuator heat transfer. But, it is difficult to estimate actuator temperature-rise by high accuracy. Then, this paper shows the design concept that improves robots motion velocity with considering temperature-rise of actuators. And we propose the simulator to evaluate the model of heat generation. In addition, the validity of the simulator is illustrated by applying to the legged robot with wheels. As a result, we showed the proposed model and its simulator were useful, and we confirmed maximum 4.4 times improvement of locomotion velocity in high accuracy for the legged robot with wheels.

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There are a lot of robot systems that directly touch and transmit the power to the users. Though it is very important that such robot systems are developed on consideration of safety, most of them are developed without argument or with abstract argument about safety. In this paper, firstly, we insist that safety of a robot system using MR Actuator can be estimated quantitatively and ensured mechanically. Secondly, the development of the High-Speed/High-Torque MR actuator is described. Response characteristics of the developed MR actuator are improved by using flat rolled silicon steel sheet. And lastly, basic characteristics of the new MR Actuator are demonstrated.

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This paper proposes an algorithm of construction and improvement of a work environment by multiple mobile robots. In order to build a system with higher performance, there are two approaches : one is to improve robots' behaviors, and the other is to improve a their environment. In this study, we consider an environment that can be changed easily by robots to improve their task efficiency. Under this environment, it is not important that robots passively adapt their behavior (e.g. Reinforcement Learning), but robots need to actively and cooperatively change their environment. Therefore dynamic potential fields are proposed as a shared memory among robots for their cooperation. In this paper, a warehouse problem in which robots allocate and relocate stocks is introduced as an example of cooperative task of multiple robots. The stock layout in the warehouse is not designed initially, and is not fixed. Under this condition, simulation results show that the proposed algorithm achieves self-organization of stock layout and cooperation among robots according to the given task.

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A model-based control such as H-infinity one makes it possible to make a robust controller design taking non-linearity and characteristic variation of the plant into consideration. There is, however, a problem of requiring much time to perform the procedure from the modeling to the designing of the control system because of the need for a strict analysis of the phenomena to obtain a practicable model. In previous paper we proposed new design method and explained the modeling technique. This method enables to shorten the design time by representing the plant model by interpolation of vertex characteristics and construct the control system on an onboard ECU when it is possible to determine the plant characteristics from the data and knowledge accumulated in the past. In this paper we aim at controller design based on the above method, and show that the total time for design has been shortened greatly as compared with the conventional method in torque converter lock up clutch slip control systems.

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Electric power assist steering (EPAS) is popular in the market due to its superior fuel economy. The electric motor inertia, friction and their fluctuations of EPAS, however, often deteriorate steering characteristics and vehicle dynamics. Elaborate parameter tuning for assist torque control based on vehicle velocity and steering wheel velocity has been made to improve them, but it is still difficult to achieve good performances in various driving situations such as load condition, road surface friction and gradual vehicle characteristics change due to time. In this paper, a feedback strategy applying the disturbance observer, “steering velocity observer”, is proposed to compensate for the adverse influences of vehicle mass change. The satisfactory effects of the proposed control strategy are observed through the simulation and field tests by using a prototype vehicle with a pinion type EPAS.

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Rhönrad is a gymnastic tool that is interesting in terms of dynamics and control. From the governing basic equations of a Rhönrad with a fixed gymnast mass, we analyzed the fundamental characteristic of a steady Spiral motion of the Rhönrad. First, we obtained the condition for a steady Spiral motion. By examining the eigenvalues of the perturbed motion of the Rhönrad from a steady motion, we next obtained a stable region of Spiral motion against a small disturbance, and discussed a common rule of gymnast for a stable Spiral motion. We further analyzed a feasible region of the stable Spiral motion without slipage for a limited frictional coefficient. Euler's disk can be understood as a limiting Spiral motion that can be realized at zero friction.

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We examine a method of decision judgment using Event-Related Potential P300 in Communication Aid (CA) for those who have motor neuron disease, ALS (Amyotrophic Lateral Sclerosis). Taking a practical situation into consideration, we try to extract the signal about P300 under not a shield but a usual room and by a single trial. We propose to evaluate the exact decision of the user who may hope something for someone. Introducing an improved Oddball Paradigm and appropriate moving averaging, we can realize the extraction of the wave of P300 under a usual room and by a single trial. Applying a modeled waveform with quantitative conditions used in clinical diagnosis, we can obtain successful results with a higher ratio in judgment about users' decision.

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This paper proposed an approach to design a driver support system. The driver support system which prevents unsafe confirmation is useful for reducing the traffic accidents during the intersection. The support system consists of the following three parts. The role of first part is to judge if the driver's confirmation is unsafely. The judgment is based on driver's gaze angles which are measured by CCD camera. The second part is to predict the driving maneuver in order to support in the early stage. The driving maneuver is predicted by Bayesian network (BN) which the parameters are learned every individual driver. Hence the prediction is adapted to each driver. The third part is to judge whether the support is necessary based on the output of previous two parts. Because of considering both confirmation behavior and driving maneuver, it is possible to judge more correctly. The parameters to design the system is tuned by and learned from data of driving simulator (DS) experiments, where the subjects drive repeatedly on the same road including some intersections with stop signs. Using these data, the system which is based on usual driving behavior is constructed. Finally, the effect of the supporting system is shown by the results of DS experiments.

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Powered wheelchair is a useful mobility tool for severely disabled people. However, due to its limited maximum speed of 6 km/h, life style of such people as well as their activity area are limited to close area of their residence. If they use automobiles that they can get on easily from their wheelchairs, and they can drive by joystick instead of steering wheel, it is greatly expected that their quality of life must be raised. This paper discusses on the development of the control system, which aims to make the disabled manipulate vehicle more safely, based on the concept of our past studies dealing with joystick driving. In order to lower the price of the newly developed vehicle, the design of one-person-ride motorcycle class proto-car is presented here. Among these topics, however, the design method of manipulating system is mainly discussed in this paper.

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The nonlinear Predictive Control theory proposed by Lu is extended to provide a framework of model following control and to take into account the effects of deterministic disturbances. The response of nonlinear, continuous system at one-step ahead is predicted by series expansion of the state equation. Control inputs are determined by continuous minimization of predicted tracking errors. The proposed approach is applied to the rear-wheel steering control of motor vehicles. The effectiveness of this control method is examined through a series of computer simulations.

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As higher precision machining in required, reducing thermal deformation of a machine tool becomes more important. In the previous report, a new method for estimating optimum temperature of cooling oil on a spindle was established. Inverse analysis using neural network was used for calculating optimum oil temperature, because neural network is suitable for controlling non-linear phenomenon. In this paper, a lathe with a simple and intelligence control of thermal deformation using neural network was developed and evaluated for high precision. At first, in the experiment, thermal behavior of a lathe was measured for a few basic study data of the neural network. Next, the neural network was used to lean the relationship between the measured temperatures and the thermal deformation on the lathe. Then the neural network was rewrote for some algebraic equations, and the algebraic equations were carried in the lathe with a PC. At last, thermal deformation was controlled in the NC program by using both the algebraic equations and temperature distribution of the lathe. It is concluded from the results that (1) The proposed method was effective in order to reduce thermal deformation. (2) Necessary device for the proposed method was only measuring device of temperature, and a forced cooling device or a linear scale were not necessary.

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The present paper deals with the relation between the temperature rise and the thermal deformation of commercially mass produced machining centers in order to develop a methodology to compensate the thermal deformation. It is confirmed by experiments that the ratio of thermal deformation to the temperature rise is almost constant regardless of the differences in the individual machines and the preload condition of the main bearings. The methods are developed to estimate the thermal deformation of the spindle based on the temperature change of the spindle head measured under the transient conditions of temperature rise and fall as well as the steady state, and their validity is confirmed by experimental data.

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Injection tests of mixed wood powders of Cryptomeria japonica with Hinoki (Chamaecyparis) were carried out at various injection conditions ; injection pressure and its holding time, container and cavity temperatures, moisture content of wood powders, in order to confirm the possibility of near net shape forming of wood powders. Effects of injection conditions on the injection pressure-punch stroke relationships, the mechanical properties, bending strength and bulk density of injected products were discussed. The experimental results showed that the wood powders could not be injected into the cavity when a initial moisture content was 12% due to less fluidity of wood powders. The optimum conditions of container and cavity temperature existed regarding of the initial moisture content of wood powders. Successful injection mouldings were performed within the container temperature T_c=90-130°C and the cavity temperature T_v=150±20°C when the initial moisture content 100% powders were used. And also the injection pressure became small at the optimum mould temperature conditions since the fluidity of wood powders became improve. The bulk density and bending strength of injected product increase with increasing container and cavity temperature. However, an optimum condition existed for the initial moisture content of powders where the bulk density and bending strength became max. Maximum relative density and bending strength were 0.95 and 25 MPa at the container temperature T_c=130°C and the cavity temperature T_v=170°C with initial moisture content 100% wood powders. Finally, it was also found that if the arbitrary cavity was using under appropriate injection conditions, it was possible to obtain the wood powders products with arbitrary shape.

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The fatigue failure mechanism is complex in synchronous belts because the boundary condition of running belts is strongly affected by the meshing condition of the belt and pulley. In this paper, discussing the effects of torque condition and tooth profile on the shearing strain initiation near tooth root, a reasonable parameter to express the relation between the shearing strain initiation and many power transmission factors, such as belt tension, tooth load, tooth height and so on. The shape of tooth load distribution on working flank is a reasonable parameter to simplify the relations between the strain initiation and the transmission factors.

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This study proposes the combination of some hydrodynamic pressure shapes formed on the end surface or on the annular surface of porous oil impregnated sintered bearing as a DC spindle motor's bearing system, and examines experimentally to optimize the hydrodynamic shape combination as thrust-radial composite bearing. Hydro Wave Bearing or Pump in as a thrust hydrodynamic shape, and Herringbone, Three lobed type or Sleeve (as a standard) as a radial hydrodynamic shape, were proposed, and the total of six kinds of combinations was produced as thrust-radial composite bearing. Floatation, temperature rise, friction torque and shaft whirling, such as the lubrication characteristics were examined experimentally. As experimental results, it was confirmed that low shaft whirling, energy-saving and life-longevity of bearing itself, were achieved by hydrodynamic pressure interaction of thrust-radial composite bearing.

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