Active sound insulation control effect of a flexible thin plate using piezoelectric film, especially for the cases in which the plate were much more thinner than that reported in the conventional studies, was investigated theoretically and experimentally. At first, fundamental equations were summarized for a rectangular thin plate with rectangular-shaped piezoelectric film sensor and actuator. Then, vibration response of the plate and sensor output response of the piezoelectric film was derived based on the modal expansion method. Output frequency response of the system was estimated by the volume velocity, which was one of the suitable indexes when sound insulation effects were discussed. Finally, active sound insulation experiment of an acrylic plate of thickness around 0.3mm with a bonded PVDF film actuator was performed to verify the fundamental characteristics and performances of the proposed controlled structures.

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This paper presents seismic evaluation of double building models by a double inertia type common seismic stage, and presents performance evaluation of a simple passive MR damper. Notch property of double inertia seismic stage could decrease the major peak of double building. The method of resistance force measurement which links between the virtual fixed ground and the upper inertia of seismic stage, suggests the fixed ground hook damper.

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For unmanned helicopters to be used in industrial applications, autonomous flight control is necessary. This study aims to shorten the time required to tune a controller and design a stable control system for model variation of unmanned multi-rotor helicopters. Designing model based controllers requires a significant amount of time and effort for model identification and the tuning of controller parameters. Additionally, changes in the dynamics of the plant lead to deterioration of control performance. In this paper, we design indirect model reference adaptive control having on-line system identification mechanism for change-of-altitude direction of a helicopter to solve the problems that have been presented. In order to guarantee the minimum phase property of the altitude model, we use the delta operator for system identification. We demonstrate the validity of the proposed control system by way of a flight experiment. The experimental result shows we were able to design a highly precise altitude controller in about 15 seconds.

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With the development of research on UAVs and widely using. The safety and reliability of the UAV system become more and more important. As a complex system, multi-rotor UAVs are equipped with variety of sensors, such as Gyro sensor, GPS, IMU, pressure sensor and so on. At the same time, because of the characteristic which multi-rotor UAV is provided with multiple propulsion parts. The risk of motor and rotor failure is higher than single rotor helicopter. As the above reasons, sensor failure and propulsion failure are considered the most primary failure of multi-rotor UAVs. This paper is fixed on motor, motor drive and rotor failure detection and the control allocation problem under motor stopped.

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In this study, we design the adaptive control system for multi-rotor helicopter. Currently, multi-rotor helicopter has been used not only for research and development but also many practical tasks. However, controller tuning of the multi-rotor helicopter is still depend on human operator, and it is an obstacle for construction of the market of the multi-rotor helicopter. On such background, Simple Adaptive Control (SAC) is applied to the multi-rotor helicopter to realize auto-tuning system. Firstly, mathematical model of the helicopter is derived. Next, adaptive PID controller with Parallel Feedforward Compensator (PFC) is designed based on derived mathematical model. Finally, numerical simulation is carried out to verify the effectiveness of proposed adaptive control system.

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In this paper, we implement repetitive disturbance observer in a controller of unmanned aerial vehicles (UAVs). Thereby, we realize disturbance estimation with high precision and build a map of disturbance information. We also implement model predictive control (MPC) that considers the estimated disturbance by considering it in the model as prior disturbance information using the map. We consider the situation that the UAV follows the reference trajectory of circle. On this occasion, the UAV estimates the disturbance information on the flight path using time state control form. The UAV updates the disturbance map based on the previous map and flight information, and the disturbance is estimated with high precision. The UAV uses it as prior disturbance information when the UAV flies on the next laps. Therefore, the UAV achieves a good tracking performance. We confirm it by numerical simulation.

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This paper deals with an experimental validation of a formation control algorithm for a multi-UAV(Unmanned Aerial Vehicle) system by using LMI(Linear Matrix Inequality) conditions. First, we show a linearized model of UAVs like quadrotors, and then, we introduce a formation control algorithm based on a consensus algorithm, a leader-follower structure, graph theory and Lyapunov stability theorem for a liner system. Second, we show the control algorithm using Lyapunov theorem and LMI conditions in the case of intermittent communication. Then, experimental results show the stability of the proposed formation control even if some network links are disconnected.

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In this study, we aim at realizing autonomous formation flight of multiple small unmanned helicopters. In such situation, collision avoidance of the helicopters should be considered in guidance control system to improve safety and reliability of the flight system. In our previous study, collision-free guidance control system has been designed by using Model Predictive Control (MPC). Trajectory generation considering collision avoidance has been realized by MPC. However, tracking performance has not been considered, and it is necessary for precise formation flight. In this paper, Differencial Flatness based tracking controller is designed to improve the tracking performance. Then, MPC and Differencial Flatness based guidance control system is proposed for precise formation flight of multiple small unmanned helicopter. Finally, numerical simulation is carried out to verify the effectiveness of proposed guidance control system.

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In this study, the optimal mechanical design method for model of fixed-pitch coaxial-rotor helicopter is proposed. The fixed-pitch coaxial-rotor helicopter has several advantages compared with other type helicopters. For example, it has great simplicity of the mechanisms, well maintainability, and well energy conversion efficiency, and so on. However, fixed-pitch coaxial-rotor helicopter has a drawback in forward flight named pitch-up phenomenon. Pitch-up phenomenon causes a little cruise speed of the helicopter, and it is fatal problem. To overcome such a problem, optimal mechanical design of the fixed-pitch coaxial-rotor helicopter is proposed. The optimal design is based on the precise mathematical model and numerical optimization method. The mechanical parameters are examined to maximize the cruise speed of the helicopter model. Mechanical parameter optimization based on mathematical model and Particle Swarm Optimization (PSO) method is proposed. The fundamental optimization of mechanical parameter is performed to show the validity of proposed optimal design method.

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This paper proposes a robust optimal attitude control design for hexarotor unmanned aerial vehicles (UAVs) under the effects of uncertainties which consist of external disturbances, nonlinear dynamics, coupling, and parametric uncertainties. The proposed optimal control is designed for pitch, roll, and yaw subsystems and it consists of a nominal optimal controller and a plug-in gain scheduling robust compensator. The nominal optimal controller is based on linear quadratic regulator (LQR) control approach to ensure a stable closed-loop nominal system, whilst a plug-in gain scheduling robust compensator is added in order to improve the attitude tracking performance due to the presence of uncertainties where the amount of uncertainties are changing dynamically. The simulation results prove the attitude tracking errors are bounded in specified boundaries and demonstrate the robustness of the proposed control scheme and thus suitable for real flight condition.

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The goal of this work is to enhance personal mobility vehicles (PMV) with autonomous vehicle technologies, such as autonomous cruise control to realize vehicle platooning and new potentials for next generation urban transportation system. This work reports our development on an automatic vehicle following system for autonomous platooning of PMV. We have developed a 3D sensing system for front vehicle detection in lateral lane keeping and longitudinal distance sensing We have implemented and conducted experiments of the automatic vehicle following system, and validated with the test runs of autonomous vehicle platooning.

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In this paper, we propose a parking control method with multiple switching motions using path-following control for front steering vehicles. The switching points are optimized using model predictive control. Moreover, the parking control is realized changing the vehicle moving direction to apposite one by multiple switching motions. We use time-state control form in order to achieve path-following control and linearize vehicle dynamics. The performance of the proposed method is verified through experiments and numerical simulations which show that the parking control is feasible in larger area than conventional method.

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This paper proposes an image-based robust hovering control for multirotor aerial robot under the effects of uncertainties in the vehicle dynamics which contain external disturbances, nonlinear dynamics, coupling, and parametric uncertainties. The proposed image-based control capable to control the pose (position and orientation) of the aerial robot relative to the fixed-target points, using visual features extracted from the image. The proposed controller scheme consists of two parts: spherical image-based visual servoing (IBVS) controller and a robust flight controller based on robust compensating technique for velocity and attitude control. The robust compensator based on second order robust filter is added to improve the attitude tracking performance when the aerial robot leaves the nominal conditions due to presence of uncertainties. Compared to other methods, the proposed method is robust against uncertainties, does not need to keep features in the field of view, and effective in the environment which pose estimation of target is difficult. The simulation results prove the effectiveness and robustness of the proposed controller and show the high potential in the outdoor flight condition.

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In this study, we aim at achieving an autonomous locomotion of the mobile robot in the unknown indoor environment. In priori research, landmark construction based on image and shape features is proposed and the effectiveness of combined landmark is verified by simulation and experiment. We propose a automatic construction method of combined landmark from image and point cloud. To devide attracted scene, we clustering image and shape feature point and calculate each feature value. If image and shape feature value are more than threshold, this method decide that the cluster is landmark. The effectiveness of proposed method is verified by experiment.

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This study expresses a novel active vibration control method for a house structure by using magnetic levitation. The magnetic levitation system is easy to install to the ceiling because there is no need to use linear guides or bearings. In this study, a magnetic levitation device is attached to the iron plate fixed firmly to ceiling of the structure and it will levitate when a vibration occurs. The total mass of structure will be decreased while levitating, resulting in the change of its natural frequency. Moreover, an efficient vibration control method is examined. Finally the results of experiments are shown to confirm its feasibility.

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A switching stiffness control was applied to reduce vibration in the lateral directions in active magnetic suspension system with electromagnets operated in the differential mode. The magnetic suspension system using the attractive force between magnetized bodies is inherently unstable in the normal direction so that feedback control is necessary to achieve stable suspension. In contrast, it is usually stable in the lateral directions because of the edge effects in the magnetic circuits. However, damping in the lateral directions is poor so that vibration is easily induced. In this work, a switching stiffness control was applied to attenuate such vibration. The effectiveness of the switching stiffness control was confirmed experimentally. In addition, a modified control method that varies stiffness continuously was proposed to overcome problems occurring in switching. The efficacy of the modified control method was also confirmed experimentally.

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In this paper, we show a Gain Scheduling(GS) controller design method for Active Magnetic Bearing System(AMB). Gyroscopic effect corresponding to the rotational speed of the shaft occurs in a magnetic bearing system. Therefore, the shaft of AMB becomes unstable. The time-varying parameter is rotational speed. The varying parameter can be measured on line. By designing the GS controller,it has a scheduling parameter of a rotational speed of the shaft, we try to guarantee stability and improve the control performance. The problem can be formulated as solving finite set of linear matrix inequalities. The effectiveness of the proposed method is verified by simulation.

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New Hybrid (HB) type Active Magnetic Bearing (AMB) is proposed in this paper. It is intended to apply to high speed turbo machinery. This magnetic bearing is easily controlled by a standard linear power amplifier. The proposed magnetic bearing has good characteristics of high efficiency, good dynamic property and easy manufacturing. The proposed magnetic bearing is analysed through FEM analysis and their properties are compared with the standard electro-magnet type one.

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In order to develop a ventricular assist device which have low power consumption and wide operating region, a double side stator type axial self-bearing motor was proposed and developed. In addition, the motor was combined in a magnetically levitated pump. The axial self-bearing motor is characterized by the inclination motion control function. The self-bearing motor was fabricated and its fundamental characteristics as were measured. In addition, the magnetically levitated pump was designed with 3D-CAD and was fabricated by a rapid prototyping. The motor could rotate stably and rotation speed was up to 4,000 min^<-1> both in air and in water.

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This paper introduces the initial design and FEM analysis of a non-contact energy transfer method for magnetically levitated linear slider platform. The non-contact energy transfer method utilizes an open-end generator and a long rotating permanent magnet array driven by a synchronous ac electric motor. The proposed non-contact energy transfer method is simple to construct and to isolate and requires minimum maintenance. The system can overcome difficulties related to the charging of batteries and the utilization of energized coil arrays in magnetically levitated linear slider systems. However, cogging forces orthogonal to traveling direction of the platform are induced on the levitating platform, due to permanent magnets and soft magnetic steel core of the open-end generator. Therefore, the complexity of levitation controller is increased. The results of FEM analysis show that the concept is feasible for prototype fabrication. Magnetically levitated linear slider systems have practical applications in the ultra-clean manufacturing environments needed for LCD and semiconductor fabrication.

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In order to develop high-efficiency, maintenance-free and small-sized hydrodynamic generators, a permanent magnet hybrid magnetic bearing was applied to support the water wheel. The magnetic bearing is small but has a strong bearing capacity. This paper investigates power generation characteristics depend on control algorithm and control device (i.e. DSP and FPGA). By use of FPGA controller, energy consumption was reduced and portability was increased.

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Vibration of a swashplate in swashplate type axial piston pumps and motors is considered in the slipper model. The theoretical model is established in consideration of vibration of the counter surface of the slipper and the calculation is performed under unsteady mixed lubrication. The representative parameters are as follows: the supply pressure of 21 MPa, the rotational speed of 25 rps, the slipper radius of 10 mm, the revolution radius of 30 mm, and the oil viscosity of 32 mPa・s. The motion, flow rate, contact pressure, and power loss are shown and the effects of the swashplate vibration and the operating conditions on the tribological characteristics of the slipper are discussed.

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In this paper, we propose a trajectory tracking method for hydraulic excavators considering constraint of attitude angle of the bucket by model predictive control. The digging operation becomes possible by tracking the reference trajectory keeping the constraint for the attitude angle of the bucket. Target input is decided by the inverse kinematics for the finished shape. Then, we perform the trajectory tracking control on the bucket tip by MPC. The efficacy of the proposed method is shown through comparing with a servo mechanism in simulations.

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In the field of marine construction, traffic ships are used to board/go ashore to the floating structure such as working vessels. However, traffic ships are fluctuated in such environments as tidal waves, and workers face an increased risk of accidents such as falls in the sea and pinched between traffic ships and floating structure. Therefore, it is great issue to be resolved. Then, we focus attention on the possibility to contribute safety and workability out of consideration of ship fluctuation if anywhere on the fluctuated working vessels will be kept in a horizontal position. The active vibration compensator with Stewart Platform is a new concept of traffic ships, which has a motion stabilized platform. The platform is supported on the main hull by means of 6-D.O.F hydraulic parallel mechanism which act to absorb motion of main hull in accordance with the control signal from an on-board computer and motion sensors. Trial results show that 66%-84% of the heave, roll and pitch motion of the main hull is absorbed and the platform is kept almost horizontal.

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Using a hydraulic flow control valve actuated by a linear solenoid instead of the control valve actuated by a hydraulic control valve is valid for miniaturization and light weighting of automatic transmissions. However, it requires advanced control so as to be robust against a flow force in a cylinder and a change of a supply pressure. To design the controller and evaluate the control performance, a precise model of the hydraulic flow control valve is required. This paper describes a precise modeling of a hydraulic flow control valve actuated by a linear solenoid. The accuracy of the obtained model is evaluated by comparing the outputs of the model with that obtained by exqeriments.

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Many studies have shown that pulsed air jet has a high removal power with little air consumptions. The purpose of this study was to elucidate dust removal mechanism of pulsed air. This paper presents measurement results obtained on the wall pressure measurement and the air consumption measurement. Measurement results of the wall pressure measurement show the most efficient removal condition is duty factor 40% at frequency 5[Hz]. In the air consumption measurement, as compared with normal air jet, the condition have realized a 56% reduction of air consumptions. In the particle removal experiment, all conditions have high removal rate. The results show the particle removal rate and the air consumption are independent. Here we have confirmed the pulsed air is a technique that can reduce air consumption.

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Since a pneumatic system has fluid-flow and thermal fields. Therefore, in modeling a pneumatic system by bond-graph, two kinds of bonds, multi-port C element and multi-port R one have been used, which are not necessary in modeling of a hydraulic system in general. And, the resulting bond-graph model becomes complicated. In this study, a bond-graph method for modelling a pneumatic system is proposed. In modeling of fluid flow and thermal field in a pneumatic system, pseudo bond-graph is employed. And, only 1-port C and 1-port R elements are used for modeling of this system. To confirm the usefulness of the proposed method, simulations and experiments for a pneumatic system used an air gripper as an actuator.

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In recent years, we have two problems for aging society in Japan. One is the problem that the elderly people are sometimes fall out of bed. This is likely to occur by rolling over of the elderly people. So it is reported that the care of constant attendance is required. By the way, the other is the bedsore problem of bedridden patients. The bedridden elderly people have a problem that they cause the congestion or the pressure ulcer. This is because they keep the same posture for a long time and the pressured body has been inhibited. So it is essential to change the postural of the patients. Further, the burden of caretakers is large. Therefore, in this study, we develop an active sensing mat that is effective for prevention of the congestion and the falls from bed. In addition, we reveal the effectiveness of the proposed mat through some experimental results.

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This paper addresses clutch engagement torque control at the start-up of the automated manual transmission (AMT) used for track. In this method, by updating the optimal control gains that are applied to the clutch engagement torque control in real time, it is possible to reflect the driver's intention for control of the operation. However, this control system includes uncertainty caused by engine throttle operating width. This paper describes the robustness of the optimal control system for the uncertainty.

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In previous paper, authors have been conducting the research on stair climbing 8 wheels robot vehicle "Octal Wheel". This robot was used reverse-phase four-wheel steering (4WS) mechanism and operated by the manual using the remote controller. The reverse-phase 4WS has the feature that the inner wheel difference does not occur. In order to easily operate the robot vehicle with three-dimensional space including the stairs by anyone, this robot is required autonomous mobile ability. For this reason, this paper attempts an autonomous mobile at level ground as the first stage. In other previous study, authors proposed the self-localization system using the LRF and the map, and the lateral guiding method SSM for the reverse-phase 4WS vehicle. "Octal Wheel" is installed those methods. However, the self-localization system achieves without odometry and other sensor data. The experiment is autonomous mobile in 3m width indoor corridor environment by "Octal wheel". The experimental result shows in autonomous mobile without contacting with other obstacles. And the following error is under 0.05m at the straight way points line.

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To reduce the collision shock and injury risk to an infant in an in-car crib (or in a child safety bed) during a car crash, it is necessary to keep the force acting on the crib constant and below a certain allowable value. To this end, we propose a semi-active in-car crib with joint application of regular and inverted pendulum mechanisms. The crib is supported like a pendulum by arms, and the pendulum system is supported like an inverted pendulum by arms. This system not only reduces the impulsive force but also transfers the force to the infant's back using a spin control system, i.e., the force acts perpendicularly on the crib. The spin control system was developed previously. The present study focuses on the development of a crib movement system. In this paper, the effectiveness of the proposed in-car crib system is confirmed by the model experiment. The results show that the maximum acceleration of the crib in case of the crib moved is smaller than that in case of the crib fixed. Therefore, it is clarified that the proposed system is able to reduce the maximum acceleration affecting the infant in the crib. Then, the control law, which feeds back the acceleration of the crib, is proposed, and the effectiveness is examined using numerical simulation.

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This paper proposes a VTOL UAV for surveying over the hazardous aria after natural disasters. A fixed wing type UAV has an advantage to the long-distance flight, but it is required run way. Our idea of VTOL UAV is combined with trirotor type helicopter and fixed wing. Previous paper developed a hovering control system which is constructed with two single-rotors in the front, a one motor type coaxial rotor in the rear and a tilt servo motor in the rear to control the angle of coaxial mechanism. The problem of this mechanism was the tilt servo motor. In order to remove this mechanism, this paper is applied a trirotor layout UAV with four rotors with fixed wing. In order to show the advantage of this UAV, the hovering test and wind tunnel test are done.

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Safety is the most important to the mobile robots that coexist with human. In order to put those into practice, mobile robots need to plan trajectory considering human trajectory. In the field of mobile robots, there are a lot of trajectory planning methods that take account of human trajectory. However, it is still difficult to avoid human in the corner because there are blind areas in mounted sensors. Moreover it is difficult to predict human trajectory in the corner. This study proposes a predictive method of human trajectory by environmental sensors. First, we gathered human trajectory data at a crossroads using environmental sensors and estimated position of gravity point of human using Extended Kalman Filter. Second, we constructed human transfer models using Vector Auto Regressive Models. Third, we predicted human trajectory using the constructed models. Finally, we validated the constructed models comparing with predicted trajectory and experimental data.

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In this study, we conduct experiments of human balancing task and present a stochastic dynamic model of the human balancing task. The parameters of the stochastic dynamic model are identified using particle swarm optimizers. Tn order to examine stochastic behavior of the human balancing, we experimentally estimate probability density function of the state quantities. The experimental result implies that the behavior of the human balance seems to be fat-tailed distribution. This experimental observation was reproduced by the model that has additive and multiplicative white Gaussian noise. This work has implications for designing human-like motions of artificial agents such as human-like partner robots.

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In recent years, new electric skateboards have been developed. However, the standing vehicles are difficult to hold rider's balance in general. This paper discusses acceleration control of electric skateboards to ride it easy. As very few studies have been reported on human standing model on frontal plane, we built a model by impulse response test which moves support surface in the previous report. The purpose of this study is to reduce the sway of a passenger by applying feedforward control to the impulse response model. We define the subject as a damped 1 DOF system and adopted a method which minimizes oscillation around the equilibrium angle in constant acceleration period. The effectiveness of the present control method and the model was tested through rest-to-rest control tests. The results showed that the presented acceleration control method can decrease the range of human motion and reaction force from the support surface in comparison with constant acceleration control.

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This paper presents an improved leg tracking method using a laser range sensor (LRS) for a gait measurement system to evaluate the motor function in walk tests such as the timed up & go test (TUG). The system tracks both legs and measures the trajectory of both legs. Particularly during the turning motion in the TUG, both legs might be close to each other and one leg might be hidden from the sensor. In addition, the moving direction of the leg rapidly changes. These situations are likely to lead to false tracking. To solve these problems, a novel data association method considering the gait phase is proposed. From the experimental results with young people, we confirm that the proposed methods can reduce the chances of false tracking, hi addition, we verify the measurement accuracy of the leg trajectory compared with a three-dimensional motion analysis system (VICON).

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This paper analyzes the synchronization modes in the system consisting two metronomes hanging from a plate. Using the model of a metronome with the torque being a discontinuous function of angle and angular velocity of the pendulum, this paper derives its describing function and shows how to obtain analytically the frequencies and amplitudes of the possible synchronized modes in the system.

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This paper analyzes motion of an object that bounces on a vibrating plate. The object is composed of two masses and a Kelvin-Voigt material having the properties both of elasticity and viscosity. This study focuses on the case where the object is vertically deformable and does not rotate. We use the stroboscopic map as a Poincare map and calculate the Lyapunov exponents and the 1-parameter bifurcation diagram. In this system, a rich variety of nonlinear phenomena such as chaos, periodic widows, quasi-periodic oscillation, and so on are observed.

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This report considers the synchronization problem of chaotic systems with delay couplings. We have already proposed an estimation method for partial synchronization conditions and have shown the relationship between partial synchronization patterns and eigenvectors of the graph Laplacian of networks. By using this estimation method, this paper attempts to analyze partial synchronization patterns emerged in the Cartesian product network systems with time-delay. Illustrative examples are included to demonstrate the validity of the analysis.

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This paper presents a design method of output sliding mode control with two degree of freedom. A dynamic pre-compensator and integral action with respect to tracking error are introduced to guarantee the existence of sliding mode and to reduce the tracking error in steady state. Feedforward compensation can achieve transient response. In order to determine the design parameters, Bezout equation and classical frequency response are effectively employed.

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In this paper, we show a convergence analysis of extremum seeking control, which is a real-time optimization method for adaptive control, for static systems based on Lyapunov-like analysis. The scheme shown in this paper incorporates an additional element into a conventional extremum seeking scheme, and this enables to guarantee the global convergence of a parameter to an optimal value under some conditions. In this paper, we show conditions of parameters in the extremum seeking to guarantee the global convergence. A numerical result is also shown in this paper.

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In this paper, we consider a landing motion control problem of 4-link robots which imitates a standing human. We note in this work that when both of the toe and the heel touch the ground, the robot becomes a fully actuated system. That is, it is possible to decouple the position of the center of mass (CoM) and the angular momentum about CoM by input transformation. Then, we can consider only three terms about CoM, vertical position, horizontal position, and angular momentum for motion control. First of all, vertical position control of CoM is built based on trajectory design to keep floor reaction force as weak as possible. Secondly, we introduce a Zero Moment Point (ZMP), and control the horizontal position of CoM to keep ZMP within the sole range. Thirdly, the angular momentum is controlled to be gradually converged to zero so that the robot stops after landing motion. Finally, we confirm the effectiveness of the present method by simulations.

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This paper proposes a squat jumping motion control scheme for 4-link robots. The 4-link robot models a human body by 4 links and 3 actuators. Therefore, this system is underactuated and has variable physical constraints during jumping motion, which makes diffucult to control this system. In this work, we design trajectories of the center of gravity to achieve squat jumping motion. Then, we apply input-output linearization and output zeroing control to the system for the designed trajectory. We finally demonstrate the effectiveness of the present approach via simulations.

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This paper presents a control strategy for a wheeled mobile robot with variable pitch blades which make it highly mobile over irregular terrain. A mathematical model of the robot is developed when it is climbing a step, and input-output linearization is employed together with integral sliding mode control for robust performance against model uncertainty such as road adhesion property.

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In recent years, injury of personnel by bomb called IED (Improvised Explosive Device) is increasing in conflict areas. IED is difficult to find, because there are many different type of IED and the explosion power is not constant. Therefore, MRAP (Mine Resistant Ambush Protected) Vehicle and BMS (Blast Mitigation Seats) are being developed in some countries. In this paper, we develop the system of the seat to reduce the acceleration from the explosion-shock for BMS. We developed new electromagnetic support system. The response of new system is more quick than the conventional mechanism and the response threshold is adjustable. The effect of the electromagnetic support system was confirmed by experiment.

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Traffic jam on highway causes environmental pollution, economic and time losses. Moreover, car drivers are exhausted by traffic jam. To improve road traffic problems including traffic jam, a work on ITS (Intelligent Transport System) is now in progress. Inter-vehicular distance control is one of approaches in ITS: Vehicles make a platoon and are running with keeping appropriate inter- vehicular distance. In this paper, we propose inter-vehicular distance control considering path tracking error. By considering path tracking error, we can calculate appropriate reference velocity which keeps inter-vehicular distance correctly. To show effectiveness of proposed method, we conducted two simulations: one with consideration of path tracking error and one without consideration.

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The optimal velocity (OV) model has been recognized as being effective for simulating traffic congestion. In this study, the ACC system is designed to attenuate traffic congestions. The OV model is improved for more precise modelling of the traffic congestions, then, a novel ACC logic design method is developed based on the investigation of the OV model. Various mixed flows are numerically simulated, and the results demonstrate their attenuation effects of the traffic congestion.

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The controller of haptic guidance steering control which assists a driver to steer smoothly is designed. In our previous works, the controller calculated the haptic steering torque from the error between the target trajectory and the center of gravity of the vehicle. In this study, driver model is considered to use the look ahead point instead of the center of gravity for the feedback. The experimental result using the moving-based driving simulator shows no significant improvement by using look ahead point. The control with strong feed-backing gain is wrong following performance to target trajectory.

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Reactive torque is influenced by road roughness, since a tire and a steering are connected mechanically. Therefore a driver can feel the road roughness, however as it negatively influences steering behavior, it is required to be evaluated. In this study, the influence of reactive torque on steering behavior of the driver and the vehicle motion were investigated by using the driving simulator with a motion platform. As a result, it was revealed that the steering behavior was deteriorated by disturbance noise due to road roughness.

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For front wheel steering vehicles, path-following controller consisting of guidance control and motion control has been proposed. In this method, target accelerations are calculated in guidance control; then the control inputs are calculated in motion control using vehicle dynamics and tire-model with saturation characteristic. However, the limitation of force that the vehicle can generate is not considered when the target accelerations are calculated. In the proposed method, we use model predictive control in order to consider maximum accelerations that the vehicle can generate. Thus, the control inputs satisfy the constraint of the limitation of the force. In this paper, the efficacy of the proposed method is verified through the comparison with a conventional method in path following simulations.

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