This paper deals with a model of electric car equipped with flywheel energy storage system(FESS). At first, We made electric car equipped with FESS suspended by active magnetic bearings(AMBs). Secondly, We designed the simple model of FESS rotor and electric car. Thirdly, We made IIR filter the reason why our FESS system works 8000 Hz (High speed). So, We have high-frequency noise. Therefore We made IIR Low-pass filter, not FIR filter because We want to suppress time delay. At last, We drove the car because of verifying the model and We confirmed appropriateness of our model.

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A flywheel energy storage system using an active magnetic bearing is an effective method for storing electric power and reducing energy consumption. Currently, an electrical vehicle with a flywheel energy storage system using a five-degree-of-freedom magnetic bearing has been carrying out. We apply a PID based simple adaptive control scheme designs for AMB-flywheel energy storage systems.

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An active magnetic bearing system can support a rotating shaft without any mechanical contact. Therefore it has been used such as an ultra-low temperature, a vacuum, and a clean environments. To realize the downsizing of the system and the high-speed rotation, 5-axis self-bearing motor has been proposed. In this paper, homopolar type hybrid 5-DOF self-bearing motor is proposed. The rotor consists of two rotors, two circular discs, and a permanent magnet. It possesses a motor, two radial magnetic bearings, and an axial magnetic bearing. Furthermore it is possible to control the rotor radial position without the information of the rotating angle. The analytical results show the feasibility of a compact and high reliable actuator for an artificial heart pump.

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Many serious damages may occur if any momentary voltage drop or blackout suddenly happens, especially in data centers, hospitals, railroads, and telecommunication systems. Therefore, the energy storage systems are required to affect the power system by a momentary voltage drop. Our experimental machine uses a superconducting magnetic bearing (SMB) and a permanent magnet bearing (PMB). To have more damping coefficient, the PMB including damper was proposed. This paper shows prototype flywheel energy storage system using PMB including damper and SMB. Furthermore, this paper also shows evaluation of vibration on this prototype.

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A wind-tunnel system for spinning body has been proposed to measure aerodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. Three-dimensional positioning and rotation of the body were achieved. However, due to the non-uniformity of the magnetic fields, the rotation around a horizontal axis suffered from drag torque caused by eddy current. In this paper, a self-spinning floating body with a function of adjusting the angle of the spinning axis is developed. The floator was suspended successfully with spinning around various axes.

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Our group has developed a new conveyer using superconducting levitation. The conveyer is composed of a levitated table and a conveying table. The gap between levitated table and conveying table is detected by using a Hall sensor on the superconductor. The position of the table is controlled by using the PD control. In this paper we discuss a superconducting magnetic bearing (SMB) with a central superconductor. A central superconductor improves stiffness of each direction. In addition, characteristics of magnetically levitated superconducting conveyer are studied when the levitated table moves in the horizontal direction.

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A new configuration for rotating gyros using magnetic suspension is proposed in this study. Gyro is one of inertial sensor and measuring instrument for angular velocity. In a magnetically suspended gyro (MSG), a disk-type rotor is connected to a synchronous motor through a fluid bearing and the motor is fixed to the frame of the floator. The floator is suspended by magnetic force without any mechanical contact so that high-accuracy measurement is possible. According to this concept, a 6-degree-of-freedom (DOF) active MSG was developed. However, because the MSG used magnetic attraction pulling upward against gravity, it has high power consumption. In addition, the miniaturization of the MSG was difficult because four pairs of electromagnets were arranged on opposite sides of the floator. To solve these problems, a 2-DOF active magnetically suspended micro gyro (MSMG) is designed and fabricated. In this gyro, the 4-DOF motions of the floator are constrained by a cross spring and a gimbal. The two rotational degrees of motion of the floator is controlled by four electromagnets. The gyro with such configuration is suitable for miniaturization and low-cost fabrication. This paper shows basic concepts and measurement principle of the 2-DOF active MSMG.

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In this paper, we propose a vibration suppression mechanism for superconducting magnetic bearings. The concept of this mechanism is controlling the stiffness of the rotor axis of the magnetic bearings according to the rotation velocity of the axis. To control the stiffness we propose the position feedback system of the super conductor. The position of the superconductor is controlled based on the displacement of the rotor. The aim of the proposed method is that the rotor passes the critical speed. First, the concept of the proposed mechanism is explained. Numerical simulations verify the possibility of the function of changing the stiffness. A control method of passing the critical speed is proposed and its effectiveness is proved.

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The force display touch pad is a pointing device that presents the position of the window frame or buttons on PC screen to the operator. Visually impaired persons or elderly people will be helped by the use of the PC by force feedback with this device. Screen reader is a software to transmit information on the computer screen into auditory information. We use the screen reader and the force display touch pad simultaneously. In this paper, we evaluate operationality and accessibility of the force display touch pad added auditory output.

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In recent years, exchanging the large amount of accurate information is required. Various tactile display has been investigated as the method of informing tactile sensation, which is one of the five senses. Tactile display using surface acoustic wave (SAW) has been studied, and Tele-touch system on tactile sensation during rubbing physical surface has been also proposed. In this system, dummy finger is proposed as tactile sensor where the dynamical vibration of the dummy skin is transformed to electrical signal while the finger is exploring on the physical surface. These dummy fingers were fabricated to simulate human finger as for their structure, form and hardness. However, vibration transmitted to the dummy finger is different in rubbing on physical surface, because each dummy finger has different stiffness and dumping. In this paper, dynamical model of the dummy finger and their different characteristic are studied for establish of Tele-touch system.

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Recently, computer is the necessary device for our lives. People use their own computer for information-gathering everyday. Additionally, small computer like smartphone or tablet computer become popular devices. However, it is difficult for visually-impaired persons to operate the computer because recent computer operating systems use graphical user interface (GUI). To solve the problem for visually-impaired persons, various assist devices for them have been developed. Some of them use haptic technology. Previously, we have proposed a haptic device as an aid for GUI operation for visually-impaired persons. Novint Falcon is used as a low-cost haptic device. The computer desktop GUI is represented as a virtual work-space. A graphic window is rendered as the front surface of a solid box in VR. Touching this virtual surface of the box with the haptic input device, the user can feel the entire window. Using this system, multiple-window GUI can be operated by visually-impaired persons. Discrimination experiments with such windows are reported.

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Pedestrian collision avoidance in urban environments is an important active safety technology to protect vulnerable road users and realize zero-traffic-accident society. Especially, reduction of vehicle-pedestrian collision accidents by using active vehicle control technology is a promising approach. This paper focuses on the driving situation which drivers need to negotiate pedestrians. This paper describes an autonomous pedestrian collision avoidance system by automatic braking. The intensity of braking maneuver is determined by the application of Potential Fields theory with considering occlusions. Finally, the effectiveness of the autonomous collision avoidance system is verified by computer simulation which employs driving scenario from a near-miss incident database.

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In this study, we developed a simulator system to learn operation procedures and train manual operation competence for a multirotor-based UAV. This system simulates flight behavior similar to actual UAV by using experimentally-obtained model and actually implemented source-codes on UAV pilot system. This paper describes a simulation result of flight behavior in case that a rotor is damaged. In addition, we describe about a training of operation in case that such failure occurred.

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In this study, we aim at realizing autonomous simultaneous flight of multiple small helicopters. In that situation, collision of helicopters is serious problem, and it should be considered in guidance control of each helicopter. In this paper, we construct a guidance control system for a small helicopter, which is considered with collision avoidance. Then, the collision avoidance problem is regarded as a control problem with state restrictions, and the theory of Model Predictive Control (MPC) is applied to the guidance control. Finally, the effectiveness of the control system designed in this study is verified by the simulation and the flight experiment.

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With the multi-rotor UAV growing fast in our daily life, the safety and reliability of the systems of UAV is more and more important. This work is to minimize the risks of the Mini-Surveryor(MS-06) which is exploited by NONAMI Lab. Motor and rotor failures are considered as the highest risk of the multirotor helicopter. In my work. First, I will introduce the way how to monitor the motor and rotor failures by using the PWM-I model and the way to find this model. Second, a new arrangement of the rotors of MS-06 is presented, by this way the fault-tolerant of MS-06 became higher.

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When natural disasters such as earthquake, tsunami and typhoons occurred it is necessary to gather information quickly in order to conduct rescue operations to safety. In recent years, unmanned air vehicle (UAV) has been attracting attention as a means for gathering information when natural disasters occur. UAV has a lot of advantages compared to manned airplane. For example, UAV is low cost and low risk, has high quietness and high mobility, can go into the danger zone. It is necessary to move long distance investigating multiple targets of wide range when performing missions such as aerial photograph and radiation measurement. In addition, if the remaining amount of the battery is low, if an error occurs, it is necessary to quickly return. The purpose of this study is the shortening of transit time due to the pursuit of high-speed flight and high maneuverability of MS-06. So, this study compensated the decrease in lift due to the tilt. By applying such compensation, we achieved stable acceleration in a short period of time. In addition, this study considered the stability of the MS-06 during high-speed flight.

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UAVs can be used for many applications such as the investigation of inhospitable environments, regions contaminated by nuclear radiation or hazardous material and other inaccessible areas. We designed a 5Kg payload 6-Rotor type UAV. In this paper, we present the essential for the construction of 6-Rotor type UAV and autonomous controller design technique.

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In this paper, we propose the intermeshing quadrotor helicopter which has feature of the tandem rotor helicopter and the intermeshing helicopter. Kinematic and aerodynamic characteristics of this helicopter have not yet been well known because such a helicopter does not exist so far. Therefore, we aim at conducting motion analysis of the helicopter. First, equation of motion of the helicopter is derived using multi-body dynamics. Next, we construct the system which enables that the helicopter fly manually. Finally, flight experiment was carried out to collect flight data needed for parameter identification of the model.

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This paper proposed novel design of hexarotor helicopters named Nonplanar Hexarotor. By dividing six rotors into three pairs and placing each pairs on three orthogonal planes, it is possible to decouple force and torque generation. Fully independent control of both position and orientation will be enabled by this configuration. Additionally by enclosing the whole mechanical parts with frames which protects from collision, it is possible to roll on the ground and fly narrow space. Unless it is needed to fly, it can move to the destination by rolling motion. Therefore this helicopter is suitable especially for indoor flight, such as the scene of an accident, the inspection of the sewer. There are a large number of applications. We explain a design planning, required machine elements, mathematical analysis and concrete applications.

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In recent years, UAVs play various roles through the progress of the flight control technologies. And missions such as information-gathering and aerial photography can be performed by UAVs, instead of manned aircrafts. And UAVs have advantages of the low risk of losing lives by crashes and the low maintenance cost because of no crew aboard. For the missions described above, the flight control technologies are essential for UAVs, but many flight control technologies rely on GPS. And small UAVs are suitable for operation in urban areas and mountainous areas, indoors, but GPS cannot be used in those environments. So in this study, the flight control techniques by using the optical flow sensor in GPS-denied environments are introduced. And in this paper, first, we derive a correction formula and determine a proportional coefficient of the formula experimentally by using the manipulator hand. Secondly, we test the correction formula experimentally by using Motion capture system to verify the usefulness of the correction equation. Finally, the conclusion and the future works is described.

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Recently, UAV (unmanned aerial vehicle) is used in fields of aerial photography and aerial investigation. But their propellers and rotor blades are not covered, and the thrust is generated by high rotational speed. Thus UAV has a high risk of damage. To clear up the risk of rotor blade, we present a new flying object that uses ducted fans instead of rotor blades. PI-D control was used instead of PD control, and it reduced the steady state error. We succeeded to achieve stable hovering by 3-axes (roll, pitch and yaw axis) attitude control. In this paper, we report 3 type of ducted-fan flying objects which use thrust vectoring and variable nozzle system.

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This paper presents an autonomous battery exchanging system for multirotor helicopters. we developed an autonomous battery exchanging station for industrial use Unmanned Aerial Vehicles(UAVs), which has 8 battery bays and chargers. And we also proposed precise autonomous landing method to battery exchanging station using only a low cost GPS receiver as localization sensors. The proposed solution named the "tethered landing method" is accomplished by reeling tether hooked on a heliport of battery exchanging station.

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In case of disasters or accidents, such as earthquake, typhoon and critical accidents, it may be occurred danger area that people can't enter. The areas may interfere with rescue work and wreak further damage. Flying robot which can move three-dimensionally and fly low altitude and narrow place is expected to play an important role in such disaster areas. The purpose of this study is to develop indoor autonomous flight control system using three-dimensional mapping by Laser Range Finder(LRF). If the LRF is fixed, in order to scan three-dimensionally, it is needed that flying robot to be able to move up and down. So in this study, we add three-dimension scan sensor to MS-06 that developed by Nonami laboratory.

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Recently, miniaturization and high-performance of micro-controllers and sensors have progressed of dramatic advances in integrated circuit technology. As a result high-performance unmanned air vehicle (UAV) have energetically been developed around the world. Unmanned flying robots are used to collect information at disaster area etc. However, autonomous control of a UAV requires much time and effort of modeling and control. The purpose of this study is to propose auto-tuning of the controller.

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Gyro is well known as the application as Gyro-sensor. However Gyro is also used as an actuator such as: a gyro monorail in the beginning of 20^<Th> century, a research regarding of a gyro bike in 1970's. On the other hand, a self control bike using the inertia moment was proposed. Furthermore, when rifting a cargo by a crane, a rotating suppression system of it was developed as an application of Gyro-actuator. In this paper, we propose a self standing bike using Gyro-actuator which is controlled by a computer. First, a theory of 2-stage top using Euler's equation of the rotation coordinate is proposed. Next, the modeling of a bike using the 2-stage top theory is developed. Finally, the effect of this theory is confirmed by experiments.

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This paper presents the subsidence sensing using the grouser embed a function to measure reaction force from soil for wheels of unmanned ground vehicle (UGV). The wheels which traverse loose soil like lunar surface have the grousers like puddle. The grousers transfer the trust to the wheels or the body of rovers. Therefore, the grousers are needed to traverse loose soil for wheels of UAV. The interaction between the wheel with grousers and loose soil can be expressed using kinematic model. Moreover, when the wheel is traversing loose soil, the wheel sinks into soil. The inserting angle is needed to solve these problems. If we know the inserting angle, the sinkage can be measured before the poor condition. It is very important and effective to detect the inserting angle of the wheel. In this paper, we propose the grouser with a tactile sensor and describe the results given by experiments.

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Recently, the unmanned aerial vehicle (UAV) is developed for aerial work. This study focused on unmanned helicopter that is one of UAVs. With the popularization of unmanned helicopter, some collision accidents between human body and its rotor blade happened. Now, we developed a new multi rotor helicopter which has 4 ducted-fans instead of non-covered rotors. We call this Quad Ducted-fan Helicopter. Ducted-fan's rotor blade is protected by duct. So, it clears up the risk of non-covered rotors.

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Conventional controllers used for active vibration control of smart structures often evaluate amplitude of control inputs as part of objective functions and suppress the amplitude of the inputs. The major intents of the control input amplitude suppression are energy consumption suppression and saturation prevention. However, energy regenerative vibration control systems regenerate vibration energy and larger inputs do not mean larger energy consumption. Therefore, the first intent of the control input amplitude suppression is not suitable for energy regenerative vibration control systems. In addition, saturation prevention, the second intent, should be treated as a constraint rather than part of objective functions. In this paper, a novel controller suitable for energy regenerative vibration control systems is proposed. The controller is based on model predictive control and the computational cost is reduced by using harmonic functions as basis functions of input. The approach gives good prediction of averaged regeneration power in future and the prediction can help power management of energy regenerative vibration control systems.

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An adaptive control method is proposed to suppress vibration of smart structures by using a self-organizing map (SOM), one type of neural networks. The SOM learns characteristics of given data without supervising, and categorizes high dimensional data into low dimensional maps with keeping complex relationships among data. The present method employs the SOM to estimate states of the controlled object and makes a lookup table of control input. Each node of the state estimation SOM consists of vectors including controlled responses and control input. The SOM and lookup table learn and are updated only when the effective control input is applied to the controlled object where the evaluation function of control system is defined by difference between the desired state and current state. The present method just requires information about the control response and input, resulting in implementation of the vibration control without numerical models. Numerical and experimental results are given for the smart structure fabricated by an aluminum plate and piezoelectric actuators, and effectiveness of the present method is confirmed from both results.

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In the precedent study, a method of self-sensing and model-free vibration control based on DVFB (Direct Velocity Feed Back) was proposed. However, in this method, control performance was deteriorated by the modeling error of the actuator. Therefore, in this study, we suggest a more robust method of self-sensing and model-free vibration control based on LQG (Linear-Quadratic-Gaussian) strategy. First, the relative velocity between the actuator and its installation point to the target structure is estimated by self-sensing technique. Second, the states of the actuator are estimated by Kalman filter using only the actuator model. Finally, LQR (Linear-Quadratic-Regulator) strategy is applied to design the controller for the actuator. In this paper, effectiveness of the proposed method is validated by simulation.

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In this study, we have developed a sensor prototype for vibration acceleration monitoring driven by the authors' proposed vibration energy harvester. It uses a commercial LTC3588 energy harvesting chip with capacitors and the piezo-bimorph cantilever-type energy harvester consists of the surface bonded two Macro-Fiber Composites. The power consumption of the acceleration sensor was typically 1[mW], and the driving current was typically 0.4[mA]. For vibration condition monitoring applications of industrial rotating machinery, we assumed that the typical casing or pedestal vibration amplitude of the rotating machinery was 0.71[mm/s] (RMS) according to ISO standard. This low intensity excitation condition was the input for experimental evaluation of the developed sensor prototype. The sensor prototype was able to measure the vibration acceleration of approximately 17[s] under the vibration input of 0.026[G] (RMS) at approximately 56[Hz] every two minutes. Approximately 12% of the input of vibration energy was used for driving the acceleration sensor. Therefore, estimated overall energy transfer efficiency was about 12%. The experimental results indicate the feasibility of the sensor prototype driven by piezocomposite vibration energy harvester.

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We have reported the effects of vibration loads on the power-generation characteristics of a PZT element doped with niobium (Nb), and have proposed the use of laminated PZT elements to significantly improve the power-generation characteristics of PZT elements. This paper describes an experimental and analytical study conducted to clarify the power-generation characteristics of the laminated PZT element doped with Nb under vibration loads. In the experimental study, the effects of the number of layers of the laminated PZT element, the loads and frequencies of the vibration loads and load resistances of voltage measurement circuit on the power-generation characteristics of the laminated PZT element are evaluated by vibration tests. In the analytical study, theoretical formulas on the power generation characteristics of the PZT element under the vibrational loads are derived by considering the equivalent circuit model consisting of the laminated PZT element, the load resistances and the voltmeter. The validity of the power generation theory of the laminated PZT elements under the vibrational loads is evaluated using it. From experimental results, it is confirmed that the laminated PZT element can dramatically improve the power generation characteristics as an electrical generator using the PZT elements. From analytical results, the validity of the power generation theory of the laminated PZT elements under the vibrational loads is confirmed by comparison of the experimental results and the analytical results.

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A wide-band vibration energy harvester using a Duffing-type nonlinear oscillator with self-excitation circuit is presented. For the conventional linear vibration energy harvester, the resonance frequency is matched to the source frequency, and the mechanical Q factor is designed as large as possible to maximize the oscillator's amplitude. The large Q factor, however, bounds the resonance in a narrow frequency band, and the performance of the vibration energy harvester can become extremely worse when the frequency of the vibration source fluctuates. As is well known, the resonance frequency band can be expanded by introducing the Duffing-type nonlinear oscillator. However, it is difficult for the nonlinear vibration energy harvester to maintain the regenerated power constant because such nonlinear oscillator can have multiple stable steady-state solutions in the resonance band. We introduce a self-excitation circuit with a variable resistance which has two values with negative (excitation mode) and positive (regeneration mode) switched depending on displacement and velocity of the oscillator so as to enable the oscillator entrained by the excitation only large amplitude solution. In this paper, by the method of phase reduction in the vicinity of limit cycle, phase dynamics focused on a phase difference between the oscillator and external force was introduced. Moreover, by using stable and unstable points of the oscillator introduced from phase dynamics, an analysis of entrainment characteristics to large amplitude from each phase on the limit cycle is shown. As a result, the necessity to switch the load resistance near stable point to cut power used by self-excitation mode is suggested.

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Electrical and hybrid vehicles require increasingly amounts of electrical power that might be harvested from different systems, such as the vehicle suspension. A vehicle suspension able to generate electrical power transforms the kinetic energy of vertical bound-rebound movement excited by the road roughness into electrical energy. If an electromagnetic motor and generator is used to produce electrical power, the translational bound-rebound movement has to be transformed into a rotational movement, by employing an appropriate mechanism, such as: ball screw and nut; rack and gear; hydraulic cylinder and hydraulic motor, etc. Such systems are costly, complex from a structural standpoint, and have relatively low efficiency, robustness and reliability. Oppositely, if electromagnetic induction and/or piezoelectric elements are used to produce electrical power, there is no need to transform the translational bound-rebound movement. Such systems are relatively inexpensive and simpler from a structural standpoint. In this work, a piezoelectric stack is placed inside the cylinder of an oil or colloidal damper. Working fluid produces a cyclical compression-decompression on the surface of the piezoelectric disks, and in this way the mechanical energy recovered from the rough road excitation can be partially transformed into electrical energy. Piezoelectric stack is serially mounted together with a compression helical spring in order to obtain a vehicle suspension. From excitation tests performed on a ball-screw shaker one determines the power generation performances. Thus, for a piezoelectric stack consisted of 55 annular disks with an outer diameter of 60 mm, excited at a frequency of 1-10 Hz, the generated electrical power was about 1-100 W.

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The main task of product development is to develop a good product at lower cost and to bring it to market in a shorter period. Conventional computer-aided design and computer-aided engineering (CAD/CAE) systems are well established in this regard. However, although upstream design is particularly important in product development [1] to add value and incorporate the required functions, it is difficult to apply conventional shape-based CAD/CAE systems to the upstream design stage due to the lack of design information at that stage. As a solution to this issue, we are proposing the development of a design framework called "1DCAE," which can be applied to the early design stage of product development including the conceptual and functional design phases. 1DCAE is defined as the design concepts, methods, and tools that cover the early design stage. The output of 1DCAE is input as the design requirements to a conventional CAD/CAE system, which transforms the design requirements into an actual product image. The CAD/CAE results are then fed back to 1DCAE to verify the overall functions. The 1DCAE concept is expected to realize design innovation and more innovative products. On the other hand, the product development strongly depends on the ability of engineers. Therefore we need the engineering design education aiming for product development and human resource development to realize the 1DACAE concept.

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Recent years, a system design method based on the idea of 1DCAE is proposed. 1DCAE provides the idea to perform the system design in manufacturing effectively and efficiently. These ideas realize the design site of manufacturing in a natural way. However, it is not a situation in which the idea can be educated in the field of education since the idea does not provide as a scholarly framework. Therefore, based on the idea of 1DCAE, we aim to develop an educational tool that can realize a part of these ideas through an example of control system design. This paper introduces an example of development of an educational tool by using a torsional vibration system.

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This paper introduces control systems design based on functional analysis using SysML in terms of the model based systems engineering. Optimization problem for a system of interest can be redefined including its time span and physical behavior. Functions of occupant protective control are analyzed using SysML diagrams and possible necessity to take the behavior before the knee contact with the instrument panel into consideration occurs. Thus collaboration control of a lap belt and a knee bolster is derived to reduce injuries of occupants. The optimization results show that the superior performance of reduction of the lower extremities is obtained. Also importance of dynamical model reduction is emphasized in order to not only design the control system but also understand the behavior of the system of interest.

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This paper presents driving stability control system design for a micro electric vehicle with four in-wheel motors, and shows requirement analysis in terms of driving stability and energy efficiency utilizing sequence diagrams based on the operational scenario to refine the requirement of driving stability control under low rolling resistance on the road. Based on the model provided by the benchmark problem No.3 of The Society of Automotive Engineers of Japan and The Society of Instrument and Control Engineers, we perform system identification to design a driving stability control system using independent motor torque for the four wheels. Frequency responses and modal analysis for the identified model are done and the H_∞ controller is designed to meet the demands on driving stability and energy efficiency.

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In operation of overhead crane systems, vibration suppression of the suspended load is important in order to realize accurate transportation to the target position. Therefore, we have been developing skill-less crane systems that automatically control vibration of the suspended load. In this study, we design the controller using Dual Model Matching (DMM). Then, with a control method namely IDCS, we realize the control without sensors. Then, we develop a new push button control box as an example of the typical human interface of the crane systems, and verify effectiveness of the developed crane systems from the view point of usability for human operators.

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This paper deals with joint parameters identification and control achieved by simulation environment. Using DIDIM and IDCS, identification and control methods based on simulation, help reducing difficulty in providing well tuned filters for good identification results and setting robustness of the controller for sensor noise robustness. Also it can improve the performance of the native poor controller without additional sensors by using this combination. Control experiments with the 2 DOF linear electro-mechanical positioning system including a flexible joint using the native PD controller, the CTM and the combination of DIDIM and IDCS are carried out. Comparing the results, the combination of DIDIM and IDCS shows better tracking performance than the native PD controller. Also compared with other control methods, the combination of DIDIM and IDCS shows good results reducing the vibration of the flexible joint which cannot be measured for feedback.

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Recently, vibration control with tuned mass dampers (TMD) has becoming well known technology, and there are various studies and many practical realizations. For instance, TMDs are effective for vibration problems caused by human walking on long span bridges or office floors, and also building vibration caused by wind. However, sometimes, we can not get sufficient vibration suppression performance by installed TMDs. In such cases, we have to replace the installed TMD for a new large TMD. This process normally requires high cost and long time. In order to avoid this situation, we propose "TMD booster" which can improve vibration suppression performance by just attaching the TMD booster to the existing TMD. Therefore, TMD replacing process is not required. In this paper, first, the concept of the TMD booster is described, then the control method called "Direct Velocity Force Control (DIFC)" is discussed. Finally, effectiveness of the TMD booster is shown in experiments.

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Driving simulator is an important tool for vehicle design, research development, and driving practice. The paper presents a development of a moving-based truck driving simulator, and evaluates driver sensation to the scale factor combinations of the moving platform.

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This study focuses on the skid steer of a steer-by-wire vehicle in a fallback operation mode that is to be invoked upon failure of the steering system. The optimum tire force distribution is determined with the aim of improving the maneuverability. Generally, in the skid steer mode, a vehicle is controlled using the difference between the traction/braking forces of the left and right half bodies. In other words, the direct yaw-moment control singularly turns the vehicle body, and the effects of this measure depend on the distribution of the traction/braking forces. In this study, the minimax optimization of the tire workload derived in the authors' previous study is compared with an intuitive square sum minimization. Further, the motor torque control required to follow the reference values of the traction/braking forces is derived; this control gives the reference slip ratios using the brush model. Numerical simulations are performed using CarSim, and the simulation results are used to verify the effects of the minimax optimizations.

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Among the various approaches available for the study of traffic flow, the optimal velocity (OV) model, which consists of simple equations, has been recognized as being effective for simulating traffic congestion. This model determines the reference velocity of a vehicle as a function of the distance to the preceding vehicle. Further, adaptive cruise control (ACC) has already been applied in practical situations, and the effects of the mixture of the ACC activated ones and ordinary vehicles would become very important in the near future. Considering such a scenario, this study modifies the OV model to simulate traffic congestion more accurately, and examines the effects of using the ACC system for alleviating traffic congestion using the improved model.

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We develop the small size servo press machine in this study. We will show the problem of modeling such as mechanical system. The ball screw is connected to the motor by cog belt. Elastics of a cog belt has spring characteristics. Therefore, we carried out experiment to obtain stiffness of the cog belt. The cog belt characteristic is obtained as 2 dimension of linear approximation. As a result, we are able to be modeled for performing load sensor-less.

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Active control methods are used to suppress vibrations in a pneumatic isolation table. To suppress vibration for large displacements, it is necessary to switch the control input instantaneously to the maximum or minimum input values. Therefore, active control by quantized input generated using on-off valves is suitable. To obtain high performance, it is necessary to consider the quantized action by on-off valves and input time-delay that arises from loss of pressure. In the present paper, the model predictive control method for quantized control input systems is proposed. The control input is restricted to quantized values, so the optimum control input is calculated by solving the optimum problem in real-time. Effectiveness of the proposed method is verified by numerical simulations and experiments.

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This paper is concerned with high-speed transfer control with vibration suppression and obstacle avoidance to a transfer system on a plane surface. In this study, the reference signals which is input to the motor system with a position control are optimized offline for reaching the target position in a short time, suppressing the vibration, and avoiding the obstacle. This approach offers that the cost function and the inequality constraints are induced in a quadratic problem with quadratic constraints. Then, the fast solution which derives the reference trajectories is proposed in this paper. The effectiveness of the proposed approch is verified by simulation of transfer machine on a plane surface.

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As described in this paper, we specifically examine a point-to-point (PTP) motion task of mechanical systems and present a simple trajectory generation method for suppressing the residual vibrations. In the proposed method, a PTP motion trajectory is generated by giving the output of a power series of time as the input of a cycloidal function. The generated trajectory depends on the coefficients of the power series. To cancel unwanted vibration, the coefficients are tuned by metaheuristic algorithms. The residual vibrations of mechanical systems can be suppressed by driving along the obtained trajectory, that is, the proposed vibration control method is a feedforward control technique. We deal with the PTP motion of an overhead crane with load hoisting, and demonstrate the effectiveness of the proposed method through numerical simulations. Furthermore, the proposed method is also applied to simultaneously minimize the residual vibration and the operating energy in a single-link flexible manipulator. The results obtained from this application consolidate the validity of our approach.

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As a method to generate a feedforward input that achieves high speed and high precision positioning, a polynomial-input-type final-state control has been proposed. This method can generate a feedforward input that drives an initial state to a final state in a finite time. However, the existence of the solution is not always ensured for any initial and final states. To solve this problem, a final-state control method using a polynomial and time-series data has been proposed, though, it requires an extra memory to store the time-series data. In this research, we propose a method that does not require the time-series data by introducing a negligibly-small final-state error. The effectiveness of the proposed method is verified by performing simulation and experimental study.

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Magneto-Rheological (MR) Grease was applied to a controllable clutch system, and its performance was investigated experimentally. MR Fluid is known as a functional fluid whose yield shear stress can be controlled reversibly by the applied magnetic field strength. But its peculiar characteristics may change as time passes because of sedimentation of dispersed iron particles. To overcome this defect, grease has been adopted as a carrier fluid of particles. Three-dimensional structure of thickener developed in grease is expected to prevent iron particles from settling out. In the present paper, a controllable clutch system was designed and constructed to investigate the performance of MR Grease clutch system. As a result, the transmitted torque could be controlled quite smoothly by the applied electric current to the coil equipped inside of clutch system, and the response time was estimated about 0.2s at the fastest.

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