Now displaying technology for audio and visual senses have been put to practical uses. In addition, a display that presents variable senses other than audio and visual senses is paid attentions by virtual reality researchers as the next generation virtual reality technology. This study focuses on a kinesthetic sense, and develops a novel force feedback device. In the present study, the gyroscopic momentum will be introduced to a haptic display to feedback a force to an operator. The kinesthetic sense is displayed to an operator by the synthesized torque by plural Control Moment Gyros. The effectiveness of the proposed method is confirmed by experiments.

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When we display the texture of virtual 3D objects, it is required to display both tactile and force information at the same time. Although some force displays are commercially available, a wearable tactile display should be realized display tactile information together with force information. Hence this paper proposes a novel wearable tactile display aiming for the integration with force display. Active touch is required to display tactile information more sensitively. That means it is need to recreate active touch when we display tactile information using wearable tactile display. To realize such a device, we used the squeeze film effect for tactile display, occurred by an ultrasonic vibration. In addition to this, we propose to move a sheet between finger and ultrasonic vibrator. First, we develop device using the method we propose. Then, we verified the usability of the wearable tactile display by experiments.

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In this paper, we propose an activity condition estimation method for evaluating the adequacy of medication timing in sensor-embedded house. Because the number of elderly recipients has been increasing due to population aging, and they sometimes have a serious accident caused by incorrect medication. If the adequacy will be low, self-medication support system sends emergency e-mails to their caregiver. Their activity condition is estimated based on simple fuzzy inference method. By simulation, we confirmed the method was able to evaluate the adequacy of general medication timing with satisfactory accuracy.

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This paper presents development of a P300-based brain-machine interface system for meal-assistance robots. The system consists of an electroencephalograph for measuring electroencephalogram (EEG) including P300 signal, a meal-assistance robot which is developed by SECOM CO.,LTD, a display system with a video camera for generating visual stimulus and a laptop computer. A support vector machine (SVM) is employed for four-class classification based on P300 signal. By using the developed system, it is expected that the disabled patients can have meal by only watching dishes which are displayed on the display system.

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This paper presents an electroencephalogram (EEG) classification method using hidden Markov models (HMM) in order to achieve a real-time classification for brain-machine interface (BMI). In our previous papers, frequency features of EEG signals are utilized for the classification. However, four-second long EEG signals are required in order to obtain appropriate frequency feature and it makes a real time processing for BMI difficult. In this paper, we employ HMM approach, which can deal with time-series data of EEG signals, to achieve a real time classification. Moreover, we propose a way of classifying two kinds of images from output probabilities of HMMs. The classification results show the possibility of a real-time classification.

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This study proposes the method for the strain analysis using marketed the ultra-high impedance contact type surface potential voltmeter newly developed. The piezoelectric polymer film sheet (Polyvinylidene fluoride, PVDF) was cut down in the rectangle, and the strain gages can be obtained one directional strain components. The experiments are carried out using potential volts meter and developed piezo film strain gages. As a result of the experiments, following conclusions are as follow. (1) Voltage can be measured stable using the ultra-high impedance contact type surface potential voltmeter, at the surface of piezo film gages. (2) The result of strain distribution of beam theory and resistance wire strain gages are obtained to be equivalent the voltage distribution of piezo film measured in 3-point bending and 4 point bending test of the double end support beam.

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Piezoelectric polymer film can generate large output voltage by means of dynamic load of tensile direction. On the other hand, polyimide film used in this study is able to convert voltage into heat. Therefore, in this study, we attempted to indirect visualization experiment by assembling these two films. As a result, we found temperature of polyimide film increased by output voltage of piezoelectric film caused by strain. From these experiments, potential of trial manufacturing of visualization film for strain was found.

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A liquid-packaging bag with a simple pouring lip; the bag and lip are made of plastic film is capable of delaying the discoloration and decay of liquid food products. It was inferred that this function is due to the prevention of the invasion of air and microorganisms from the pouring lip into the bag. However, the reason air and microorganisms could not enter the bag remains to be determined. In this study, to discuss the above reason, the tip of pouring lips after pouring soy sauce and seasoning soy source are observed using a light microscope and digital camera. As a result, for soy source the gap size of the tip increases with time and for seasoning soy source the size hardly increases with time. In addition, salt crystals are found at the tip for soy source and seasoning soy source.

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The relationship between the temperature and movement of ultraviolet (UV) curable resin illuminated at UV ray is investigated. A system is developed for simultaneously measuring temperature and movement of the resin. The temperature and movement are measured using infrared and digital cameras, respectively. The movement is shown as streamline patterns drawn on the basic of velocity obtained using a digital image correlation technique. Moreover, the movement is represented as the paths of particles mixed in the resin obtained using a digital image correlation technique. Results indicate that the movement of UV curable resin in curing process mainly relates to the shrinkage of the resin and hardly to the temperature of the resin.

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A semicircular polariscope which is constituted by a high-speed camera with a pixelated micro-polarization plate array and circular polarized light system (polarizer and quarter wave plate) is developed for applying to time-dependent photoelasticity. Four phase-shifted photoelastic fringe images are acquired simultaneously using the polariscope, and used to obtain two photoelastic parameters, namely, isochromatic parameter (fractional fringe order) and isoclinic parameter (isoclinic angle) using a phase-shifting technique. The polariscope is applied to investigate the ability of the camera using a circular disk subjected to a concentrated load. Results show that the polariscope is effective for determining the photoelastic parameters.

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In this research, the experimental analysis was done for the manhole cover using the three dimensional stress freezing method. The stress concentrations were confirmed at the edge of the load and the edge of the cover. With the numerical analysis, we confirmed the stress concentrations almost same as the experimental analysis. Similar evaluation was performed in covers which changed the lib interval. It has been understood that careful corresponding is necessary in the shape and size of the volume fillet surface in the safety design.

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This research made a study on hub bearing selection considered deformation control of automobile hub. Two-dimensional finite element method was used for analysis. Because, analytical results were compared with the experiment results by stress freezing method method, the tendency to the stress distribution was examined. Moreover, the drive shaft material and the load value were changed, and enhancing the hub bearing configuration selection method was tried. As a result, it has been understood to be able to select the hub bearing configuration when designing and inspecting it.

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The spline shaft is used for an important part such as cars and machine tools. Therefore, the damage of the spline shaft causes a serious accident. On the other hand, the composite material is superior to the material which consists of a single material. An interface exists in compound material and stress concentrates in an interface. In this research, a spline shaft with two aspect is defined as "different aspects spline shaft". The model was produced by using epoxy resin. In order to reproduce the crack by metal fatigue, the crack was inserted in the crack progress direction. The intensity of the spline shaft was evaluated using the stress intensity factor. The stress intensity factor was measured using the hybrid method of photoelasticity method and method of caustics. The difference in the stress intensity factor by the difference in an inside diameter was examined.

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The aim of this study was to visualize the displacement of the teeth during mandibular anterior retraction by means of the digital image correlation method. As a result, it was found that the orthodontic force duaring mandibular anterior retraction has some influence on the dental arch as a whole.

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The aim of this study was to examine the stress distribution in the maxilla on differences in the inclination degree of the maxillary anterior. We prepared a 3-dimensional finite element model (the normal model) with a total of 140,029 nodes and 762,375 elements, which included the suture palatine median, teeth, and periodontal ligament, according to cranial CT images taken from an adult dried skull. We made another model by inclining the maxillary anterior tooth of the normal model. And, we experimented by using these two models. We obtained the following results. When we compared the stress distribution of the normal model with that of the model with inclined upper incisor, the concentration of stress of 0.35 MPa or more was observed more widely in the normal model than in the inclined model. The results suggested that the tooth axis of the upper incisor influences the shape of the palate during orthodontic treatment.

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Recently, the number of foot joint syndromes by an acquired transformation increases. Because loading condition and the structure of foot joint greatly influence them, the clarification of the mechanical property of foot joint is important. Especially, a flatfoot has a lot of patients as an acquired case. In this research, the bone in the arch of a normal foot and a flat foot was reproduced by three -dimensional model, the stress distribution was analyzed by the photoelastic investigation, and it made comparative study of them. The experiment analysis result showed the following things. The remarkable difference was seen by calcaneus. In ground plane, stress concentration caused the normal foot inside. Stress decreased as the normal foot went outside. On the whole, stress increased the flatfoot. And, reduction of the stress in an outside like a normal foot was not seen.

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The ultrasonic measurement of the surface propagating wave (SPW) was carried out under fatigue testing with aluminum alloy specimens with / without a plated layer. The surface waveform was changed with increasing damage in the path of the APW, and when the fracture occurred in the path of the SPW, the wave intensity was decreased in the final stage of the fatigue life. In case of the specimen with the plated layer, the frequency of the SPW shifted to the higher frequency range with increasing number of fatigue cycles.

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Two criteria for the prediction of incipient crack path direction of non-proportional mixed mode I+II loading in rail steel are investigated. The analysis is based on 2D plane strain FE-simulations in which actual elasto-plastic stress distribution is used for the maximum tangential stress (MTS) criterion and maximum tangential stress range (MTSR) criterion. The purpose of the analysis is to compare the numerical results with experimental results. It is shown that both the MTS and MTSR criteria including plasticity and sophisticated work hardening law are well suited to predict incipient crack growth directions for the rail steel under non-proportional loading.

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Fatigue evaluation methods have been proposed based on environmental fatigue test results regarding parameters selected for simulating BWR and PWR conditions. Recently, effects of strain wave form have been discussed by comparing experimental fatigue life with predicted fatigue life evaluated by modified rate approach method. Environmental fatigue life of carbon, low-alloy and stainless steels under sine wave form was reported to be longer than that predicted in simulated BWR environment. In simulated PWR environment, however, it was reported that environmental fatigue life under sine wave form could be predicted appropriately. In this study, experimental fatigue lives of carbon steel under two kinds of strain rate changing conditions of sine wave and the wave obtained in thermal fatigue test in simulated BWR environment were compared with predicted fatigue lives. Modified rate approach method was indicated to be applicable to predict fatigue lives under these two kinds of strain rate changing conditions.

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Recently, the operating temperature of turbine components have been increasing along with a rise in turbine working fluid temperatures. Therefore, materials with high creep strength are used for turbine wheels. Not only creep strength but also oxidation of material is important. In this study, an oxidation resistant coating was applied to prevent the decrease in the fatigue life caused by oxidation in a Ni-based super alloy and the effect was examined. The results show that the fatigue life of the specimen, which contains a lot of oxides in the oxidation- resistant- coating, improved by up to 150%. Moreover, the fatigue life of the specimen, which contains few oxides in oxidation- resistant- coating, decreased up to 160%. Thus, it was shown that fatigue life can be improved by controlling the oxides in an oxidation- resistant- coating.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. The authors propose a new method for reduction of tensile residual stress in which low frequency vibration is applied during welding. First, transmission of ultrasonic vibration is examined. Second, reduction of residual stress using low frequency vibration is examined. It is concluded that low frequency vibration is transmitted to specimen well and residual stress is reduced using ultrasonic vibration.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. The authors propose a new method for reduction of tensile residual stress in which ultrasonic vibration is applied during welding. First, transmission of ultrasonic vibration is examined. Second, reduction of residual stress using ultrasonic vibration is examined. It is concluded that ultrasonic vibration is transmitted to specimen well and residual stress is reduced using ultrasonic vibration.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Reduction method of residual stress using vibration is developed. In this paper, evaluation method for reduction of residual stress is proposed. Distribution of residual stress based on experimental data is obtained and reduction rate and reduction probability of residual stress are obtained.

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Creep properties for stress mitigation simulation in post weld heat treatment (PWHT) were specified. Material properties of both the deposited metal and the base metal of nickel based alloy and austenitic stainless steel were examined. First, creep tests were conducted at 625℃, which is a holding temperature in PWHT. Test specimens were subjected to certain stresses, and creep strain rates were measured. The power law model was used to simulate the creep strain rates. Material properties for the power law model were calculated from the creep strain rate data. Then, relaxation tests were conducted at 625℃. Test specimens were subjected to certain strains, and stress mitigation was measured. The experimentally measured stress mitigation data were simulated using the power law model with the calculated material properties. The simulation data showed good agreement with the experimental data. Accordingly, the material properties calculated in this study can be considered valid.

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Metals such as titanium materials and stainless steel are widely using in orthopedic implant devices. In this work, we examined about application of thermoelastic stress measuring method for fatigue property of implantable metal. The fatigue test with Ti-6Al-4V alloy and stainless steel was conducted with sine wave at stress ratio (minimum stress/maximum stress)=0.1. The effects of wave frequency and material on the difference of surface temperature (ΔT) obtained by thermoelastic stress measuring method were examined at various applied stress using Ti-6Al-4V alloy and stainless steel. The ΔT for Ti-6Al-4V alloy and stainless steel increased with increasing applied stress. Effect of frequency on ΔT was also small for Ti-6Al-4V alloy and stainless steel. Surface stress calculated with thermoelastic parameter was also close to applied stress. It was clear that thermoelastic stress measuring method is useful for estimation of surface stress of orthopedic implant devices.

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A method to estimate dynamic fracture toughness is proposed and demonstrated for a notched, carbon steel specimen. Fracture toughness is evaluated from the size of the near crack-tip plastic zone and the yield stress. The near crack-tip plastic zone is identified with Electronic Speckle-Pattern Interferometry (ESPI), and the yield stress is obtained from a uni-axial tensile experiment. Being capable of evaluating the plastic zone, this method allows us to use the Irwin's plastic correction, and thereby especially useful for estimation of dynamic fracture toughness. The experimental result has been verified at a low pulling rate via comparison with static fracture toughness evaluated by a conventional formula. The ESPI enables us to observe the temporal variation of the plastic zone, and thereby to reveal the internal crack growth and the type of fracture.

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In this paper, we describe a method for three-dimensional high accurate analysis of a crack embeded in a large-scale structure. The Enriched Free Mesh Method (EFMM) is a method for improving the accuracy of the Free Mesh Method (FMM), which is a kind of meshless method. First, three-dimensional elasticity problem without a crack is analyzed using the EFMM and we find that its accuracy compares advantageously with the FMM, and the number of CG iterations is smaller. Next, three-dimensional structure with a crack is analyzed using the EFMM. The analysis results are agreed very well with the reference solution. It is concluded that the proposed method is very effective in the analysis of the crack embeded in a large-scale structure.

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To improve the corrosion resistance of magnesium alloy, Al alloy coated magnesium alloy laminated material using a thin sheet of zinc has been developed by solid-phase diffusion method The relationship between welding conditions and bonding strength of laminates materials fabricated using vacuum hot pressing was examined by tensile shear test. As a result, the optimal maximum shear stress was 7MPa at a bonding pressure 20MPa, a bonding temperature 603K and a bonding time 60min. Then, laminate material were hot rolling after vacuum hot pressing. The mechanical properties of laminates investigated, and the relationship between these characteristics and structure near the bonding interface was examined.

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To make clear the effect of fine-particle-peening (FPP) on the plastic deformation of materials, tensile deformation and hardness measurement tests have been performed for SP and FPP treated steels. As a result, the ductility decreases for SP treated steel, but increases that for FPP treated steel. From a change of hardness distribution of inside the steel inside during tensile deformation processes, near the surface region of FPP treated steel has more deep stable hardened layer than SP treated steel for tension deformation. It seems to be a cause of increase of a ductility of FPP treated steel that hardness distribution becomes more heterogeneous and having more deep stable hardened layer during tensile deformation.

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In this study, hot-melting mixture followed by hot-pressing molding was applied to the processing of short-random fiber reinforced composites made of kenaf bast fibers as reinforcing agent and poly(lactic acid), PLA, as matrix resin. The effects of fiber content and fiber alkali treatment on the composite mechanical properties were mainly examined. Notch effect on the static ultimate strength of the present composites was also discussed. As a result of the present tensile test, kenaf fiber introduction into PLA resin could be found to improve the composite mechanical properties, especially in case of notched specimens, which implied that kenaf fiber would certainly play a role of reinforcing agent.

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In this study, the analysis of stress distribution generated by the cornering force caused when turning to the automobile hub. The experiment uses the assumption parts of the same hub and the bearing and the load to the automobile hub has been increased by using the assumption parts of the bearing. The analysis methods are using the photoelastic method with FEM. It is clarify that the stress concentration becomes remarkable from the result by the cornering force the fillet R neighborhood in the boss root, the bolt hole, and beside contact department with the brake plate. Moreover, the FEM analysis lowers to concentration degree though the stress concentration tendency is almost corresponding in both analyses.

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Simulation model for predicting deformation and reaction force of bent cables using FEM analysis was developed. The equivalent material model was determined through the three-point bending test of cables. As the equivalent material model of the bent cable, homogeneous elastic-plastic body with kinematic hardening was proposed. The deformation of the cable bent like L-shape obtained from FEM analysis was in good agreement with experimental results.

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Austenitic stainless steel (SUS316L) surfaces were processed with a Nano-second Laser System (NLS). Changing processing parameters such as defocus distance, scanning rate and path intervals caused different effects on topography of the surfaces. The processed surface showed unique surface microstructure with complicated micro holes. The wettability of the surfaces was also examined by measuring a static and dynamic contact angle. The contact angles were changed from 0° to 137°, and the contact angle histereses decreased to 3.6° depending on the processing parameters. This suggests that the wettability of SUS316L steel surfaces can be controlled by NLS processing.

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This paper described the control method that didn't use angular sensors of the thigh link in the leg of the six-legged robot. Concretely, the amount of the state of robots was observed by the observer (Kalman filter) and applied to sliding mode control. Kalman Filter was designed by using a mathematical model in which the inputs are the driving torque of the thigh links in the supporting legs and the outputs were the body height, pitch angle, and roll angle. 3D simulations by 3DCAD model and experiments were conducted, and the effectiveness of the sliding mode control was confirmed.

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This paper presents how to improve the visual recognition ability of SONY AIBO robot. AIBO is a general purpose quadruped robot and most users enjoy the robot through interactions with AIBO by means of a variety of sensors mounted thereon. The sensors include CMOS camera, infrared ranging sensor, microphone, accelerometer, many touch sensors and so on. This study focuses on use of the CMOS camera. Recognition task of the camera is sharply affected by ambient lighting conditions. In our approach, a shutter speed is adjusted so as to improve color recognition ability under different lighting conditions. The approach is verified through experiments under a variety of conditions.

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Wheeled inverted pendulum robot can be stabilized by applying a linear controller. The purpose of this study is not only stabilizing the angle of body but also moving the robot to a desired position in a horizontal plane. First, the desired velocity of the robot for reaching the desired position is calculated by using control methods proposed for non-holonomic systems. Second, the controller for tracking the desired velocity while stabilizing the body angle is proposed. In the simulations and the experiments, some controllers based on the different control methods for non-holonomic systems are compared and evaluated.

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Having a sense of contact is vital to do an interactive task against a workpiece surface. This study aims to extend our previous research to multi-DOF haptic feedback. We developed a new 3-DOF force sensor which can be installed inside a vacuum chamber of SEM. The force sensor enables one to feel a contact force at the tip of a probe in an arbitrary direction. The paper describes design details and characteristics of the force sensor alone and experimental results when the sensor is in contact with a test specimen inside the vacuum chamber.

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In order to deal with ultra multi degree-of-freedom (DOF) dynamical systems, we designed the dynamical system as an autonomous decentralized system, and controlled its behavior using a bottom-up scheme, i.e., by setting local rules for each DOF. And we set the local rule using neural network. We considered a simplified 242-DOF mass system, with subsystems represented by point masses connected together by linear actuators. We analyzed the behavior of this dynamical system by computer simulation. We applied the local rule to switch the P gain and the D gain of the actuators to realize the function: displacement controllability. This function was found to successfully emerge in the numerical simulation results. Hence, the effectiveness of the proposed design methodology is confirmed.

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In recent years, the virtual space is used for product evaluation. The designers evaluate the products constructed in the virtual space, watching the products displayed on a monitor and recognizing the reaction force generated by a haptic device. As for the virtual information, the color gives us psychological influence. It is said that the impression of the hardness is changed by lightness of color; we feel the light color objects soft and dark color objects hard. Therefore, the recognition of reaction force may change according to the brightness or contrast of the visual information if color actually influences the human ability of perceiving force. In this study, a haptic device, PHANToM Omni, is used for displaying the reaction force when touching the object constructed in a virtual space. By using the haptic device, we confirm whether the recognition of force changes according to the lightness of object color.

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This paper dealt with a hybrid control of position/force of 2-link arm with a flexible tip using Computer Aided Engineering (CAE). Finite Element Method (FEM) was applied to model the flexibility of the tip arm. And, the behavior of the flexibility was confirmed. The modeling in the numerical formula was hard work, however, it was easy for modeling the flexible arm by using CAE. For the first step, a hybrid control of position/force that considered the highly vibration mode of the flexible arm was simulated by PID control.

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In the plate structures that consist of the frame and the panel, the panel vibration is caused to the external force that is transmitted to the panel through the frame. In this study, the optimum design method is proposed by using the correlation between components to reduce the vibration efficiently.

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This paper discusses joint rigidity at a fixture point of a rigid block that is used to estimate six-degree-of-freedom Frequency Response Functions (6-DOF FRFs). We made comparison between the FRFs obtained using FEM and the FRFs estimated through a method of the FRFs proposed by the authors, thereby demonstrating that it is possible to take highly accurate FRFs estimation. However, the results have revealed that the accuracy of the estimated FRFs is affected by joint rigidity, which depends on a contact area of rigid block. The relationship between joint rigidity and the contact area of the rigid block is examined by vibration testing in order to improve the accuracy of estimated FRFs.

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In precise active vibration isolation table, the dynamics of loads of the table often affects on the performance of the isolation table. The aim of this research is to improve the vibration isolation performance by using a controller designed with consideration for the dynamics of load. An experimental active isolation table with an elastic load is built as a control object. The dynamical behavior of the table with load is identified through FEM analysis and experimental model analysis. According to these results, three-degree-of-freedom model is specified and its property is compared with experimental results. The LQ optimal control theory is applied to the specified model and a feedback controller taking the dynamics of the table and the elastic load into consideration is obtained. Computer simulation to evaluate the performance of the controller is carried out and the controller showed good performance.

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Lunar rovers are required to move on rough terrains such as in craters and rear cliffs where it is scientifically very important to explore. Recently, wheel typed rovers are popular for planetary exploration missions. However, there is a problem that the wheel typed rovers have possibility of stack. Therefore, this paper investigates a mechanism of kinetic behavior between the wheels of the exploration rovers and loose soil. This paper proposes the flexible wheel. The flexible wheel has the surface which can be changed flexibly toward rough terrain. Running experiments on soil which imitated regolith are carried out to observe the traversability of the flexible wheel using slip ratio.

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CO_2-reduction is required in maritime industries as well as other industries. On the other hand, ship is the most energy-efficient transportation facility and it is not easy to reduce CO_2 emission from the ship. Therefore, combination of the multiple approaches for the CO_2-reduction in the ship appears promising. In this study, to achieve the energy saving in the ship, we aim to optimize the performance of the engine-propeller system, considering the ship motion. As the first step, a system simulator is developed. In the simulator, the behavior of the engine and the propeller is analyzed combining the ship hull motion. From the simulation results, it is clarified that the time scale of the fuel injection control influences the fuel consumption rate of the engine.

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In the automobile engine weight lightning task, it is important to take measure to the elastic vibrations that occur at engine operating. In this paper, the problem of engine weight lightning is definitive by light weight engine operating experiment. To evaluate effect of mount installation angle change efficiently, the vibration transmission state to the chassis is evaluated by using correlation between mount transfer force and vibration characteristic of the chassis. Indicator is made to evaluate mount performance quantitatively. Finally, it proposed the optimum adjustment method of the mount installation angle to suppress vibration transmission from light weight engine to the chassis.

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The purpose of this study is to examine the effectiveness of active seat suspension when it is applied to small cars and the problems associated with its practical use. A small active seat suspension is installed for one-seater electric automobiles. In an actual driving test, a test road, in which the concavity and convexity of an actual road surface were simulated using hard rubber, has been prepared and the control performance of vertical vibrations of the seat surface during driving has been examined. In this paper, we examined the effectiveness of the active seat suspension in outdoor. As a result, the ride comfort improvement of the small vehicle was able to confirm that active seat suspension was effective on off road.

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In this study, the moods of drivers were estimated using physiological information; fluctuations in heart rate were measured by an electrocardiogram to measure autonomic nervous activity. We estimated the level of relaxation of drivers during driving by comparing the sympathetic nervous and parasympathetic nervous activities of drivers when they are driving cars with and without an active seat suspension. A frequency analysis of the nervous activities was carried out using a real-time system that analyzes the fluctuations of heart rate. The moods of the drivers were also examined using a questionnaire to evaluate the correlation between the moods of drivers during driving estimated on the basis of electrocardiographic measurements and those estimated on the basis of responses to the questionnaire. Furthermore, their correlation was also examined by conducting a questionnaire survey with a five-point scale with three as a reference value to examine the subjective ride comfort of drivers in cars with and without an active seat suspension.

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A complex system such as a vehicle consists of many components, and system-level vibration is conducted when all components are available. In order to shorten the development time, a virtual boundary condition concept is proposed in which only a single component is used to be excited by actuators that provide appropriate interface forces from the other components. The method is verified by a simple numerical model and then applied to an actual HVAC.

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