Locomotive robots consist of wheeled, crawler type, and legged type. Dynamic walking can increase propelling velocity on the flat ground and get over the step. The Dynamixel AX12-A was used in the previous study to make the quadruped walk. The XM430-W350-T with high output torque was selected in this study. Leg length was limited from the torque of Dynamixel xm430-W350-T legs in statics analysis. Author tried to analyze the dynamics using the Lagrange equation to obtain the required torque. Author changed the robot hardware from Arduino to the more powerful Raspberry Pi4 and developed an extension board for control.

This article proposes an output zeroing control of angular momentum as a method of attitude control during a series of jumping motions from before the taking-off to after landing for hopping robots. In the proposed method, a 3-link mechanism of the robot is reductively modeled as a 2-link mechanism, and the output zero control system is designed by taking the angular momentum around the toes as an output function. Simulation results to see the validity showed that by consistently using the proposed control system from before jumping to after landing, the robot can succeed in landing while regulating the angular momentum at the taking-off and maintaining its attitude in the air.

This paper mainly demonstrate the modeling and experiment of tensegrity robot and realize passive walking gait and analyze it also. First, we combined tensegrity and rimless wheel model to build the simplest tensegrity robot model, and carried out system modeling analysis on it, mainly considering single-leg support and double-leg support. Secondly, the tension elements were simulated to analyze the influence of the elastic forces and other elements. Finally, the theoretical results were verified with the physical prototype.

Understanding the functions of a coordinated drive of biarticular and monoarticular muscles in locomotion is fundamental to establishing a control strategy of a musculoskeletal robot. However, our current understanding is inadequate due to the complexity of the musculoskeletal structure. To tackle this issue, in this study, we developed a monopod robot with a musculoskeletal system including three biarticular muscles. We investigated the relationship between the height of a jump and the drive timing of two muscles: the gastrocnemius and soleus. As a result, we found that the relationship of the drive timing determined the height of a jump. We found that driving the gastrocnemius muscle earlier than the soleus muscle improved the jump height compared to the case where it was not. We also confirmed that the robot could jump three times consecutively with the parameters achieving the highest jump in this study.

This paper discusses the relationship between the state of the upper body and the robot’s gait efficiency above an approach based on a stable gait for walking on water. First, we introduce a 6-DOF walking model and outline the system dynamics. Second, we observe the robot’s gait efficiency in terms of walking speed, stride length and step period by varying the absolute angle and length of the upper body.

In recent years, researches on humanoid robots are actively conducted, and they are expected to play an active part in various fields. However, bipedal walking, which is the main means of moving for humanoid robots, has some problems. Firstly, the movement speed is slow. Secondly, the energy efficiency is low. As a means for solving, we proposed the skating method by a biped robot which uses swaying motion. By skating, biped robots can move faster than them by walking, and can decrease the number of actuators. However, the skating robot we have developed has some problems. One of them is that the skating robot cannot decelerate and stop on its own. In order to solve this problem, I devised a stopping method for skate robots and allowed the robot to stop in the simulation. This method is based on the theory of skating movement and the stopping method used in actual skating.

Legs’ stiffness design for legged robots is essential to improve the locomotion performance, e.g., efficiency and speed of robots, which many researchers have conducted. The pioneering work, done by Galloway et al., mainly focuses on the stiffness against ‘vertical forces’ such as gravity. This paper focuses on the legs’ stiffness against the friction force, which is ‘horizontal’ to the ground, named the leg’s horizontal stiffness. We fabricate the prototype that can change the horizontal stiffness of its legs by utilizing Living Hinges. The experiment results demonstrate that mobility performance is improved by tuning the legs’ horizontal stiffness appropriately. The results shed new light on a legged robot’s design method to increase the robot’s locomotion speed.

Cursorial quadrupeds have sophisticated morphology with heterogeneity along with the lead to tail direction, realizing agile locomotor capabilities. This study aims to understand the functionality underlying the asymmetrical animal morphology to establish a new design principle beyond modern-day quadruped robots with homogeneous body structures. To this end, this study investigates the effects of flexible connectivity in the shoulder region (i.e., shoulder hammock structure) on quadrupedal running by using a simple mass-spring-damper robot system in the sagittal plane. The results suggest that flexible shoulder may reduce ground reaction force differences between the trailing and leading forelimbs in asymmetrical running gait (e.g., galloping gait).

Recently conflicts between wildlife and human becomes worldwide problem, but conservation of wild animals is also a current hot topic. We are developing a unique multilegged robot “Goat” series for animal menacing to reduce wildlife damage. For the goat series, we employed simple mechanical leg driving system - inverted Chebyshev link with 3D trot vectoring mechanism, so the durability is relative higher than conventional legged robot. We have already reported the concept model “GuardianGoat” and its partial mechanism. In this report, we will describe bear-size modified “GuardianGoat” with the wheel-leg switching mechanism, which enables the robot for practical operation in various fields.

In this study, we investigated the walking stability of quadrupedal locomotion at the various walking condition. This study aims to clarify the relationship between body stiffness and walking speed, and gait pattern. To do that, we introduced a simple model of the quadrupedal robot as a two-inertia model, and the external force from the legs’ contact points was simply modeled as a periodic twisting torque acted to the body trunk. Numerical simulations conducted a parametric study. The results show that good trunk stiffness gains walking stability according to each gait pattern.

With the consideration of achieving stable locomotion on slope with natural and simple gait as well as avoiding intricate sensing and control systems, this paper presents a biped robot walking control method that generally referred to as quasi-passive dynamic walking. First, we introduce the modeling and control method of the compass-like robot that use open-loop control to make the input torque track a specified waveform. Second, we conduct the numerical simulations to observe the typical gait, and analyze the results of it. Finally, we use arnold tongue to show exactly how large the entrainment range is.

We have changed the anisotropic stiffness of a shape memory polymer by adding a shape pattern to the polymer while maintaining a static fitting ability. The shape memory polymer can be fitted statically in the rubber state and retain their shape in the glass state. However, since the stiffness in the glass state is isotropic and rigid, it does not have deformability only in a certain direction. Therefore, we added a shape pattern to satisfy both static fitting and anisotropic stiffness. We adopted a wavy thread structure as the shape pattern, and we formulated to confirm that the stiffness changes by changing the dimensional parameters. We calculated the measure values by the tensile test in order to investigate the designing anisotropic stiffness. The ratio of the measure values in the width direction to the longer direction varied from 0.857 to 255, indicating that the anisotropy of the stiffness can be designed.

The purpose of this paper is to realize omnidirectional movement by generating a traveling wave with a simple command that only applies pressure to a bending module made of a flexible material. Also, in order to realize moving operation only by pressurization without using a solenoid valve, it is necessary to develop a pneumatic self-excited valve. The leaf spring built into the developed pneumatic self-excited valve snap bucking, creating two states : shutoff and open in two flow paths. We will develop a pneumatic self-excited valve to switch the four flow paths for generating traveling waves by combining multiple shutoffs and releases due to snap bucking of the leaf spring.

We are simultaneously developing biped walking and running robots based on passive dynamics. In this study, the vertical ground reaction force was different from that of humans in the running robot, which led to the idea of wobbling mass. In this paper, we report here because we have succeeded in developing a ground reaction force closer to that of humans by improving the wobbling mass unit.

The redundant muscle arrangement allowing for variable stiffness control is one of the most important advantages of musculoskeletal humanoids. In this study, we focus on one feature of the redundancy, which enables the humanoid to keep moving even if one of its muscles breaks, an advantage that has not been dealt with in many studies. In order to make the most of this advantage, the design of muscle arrangement is optimized by considering the maximization of minimum available torque that can be exerted when one muscle breaks. This method is applied to the elbow of a musculoskeletal humanoid Musashi with simulations, the design policy is extracted from the optimization results, and its effectiveness is confirmed with the actual robot.

Recent robots have been used in various environments and require complicated movements according to various environment. In particular, quadruped robots are expected to play a role of gaiting on rough terrain, however, it could be burden of that control systems is complicated. On the other hand, it has been suggested that the gait pattern generation of quadrupeds is related to the natural frequency of the musculoskeletal system. It is expected that the gait pattern generation is realized by the rhythmic movement of the whole body including the body and legs. To investigate the relationship between the spinal rigidity and gait patterns, we developed a simulation of numerical simulation of the actual four-legged robot with a tensegrity structure in the vertebral column and conducted a walking experiment. Experiments have displayed that it generated a gait pattern called a trot.

To closely monitor living things, it is expected to camouflage and fade the robot into the environment to. To address we focused on giving invisibility by hiding in the environment, rather than mimicry that depends on visibility by changing the color and shape. Therefore, we have developed a camouflage underwater robot that hides itself by utilizing things that are ubiquitous in the environment by the softness of its own body with soft materials. The method is to make the sand soar by generating negative pressure and waves with the softness of the body. Then cover the sand with the sand to camouflage. By giving a phase difference to the movement of the fins, it is found that negative pressure and waves are more likely to occur, improving the efficiency of camouflage.

Animals often display skillful movements involving quick movements, such as the escape behavior of shrimp. Their motions are so fast that they might be difficult to realize as responses to control inputs. To address we develop a bistable tensegrity joint and propose to achieve instantaneous flexion movement. The spine model was chosen among the tensegrity structures because it mimics the spine of animals and because it can be connected to a series of homogeneous segments. By adjusting the angle and length of the rigid members of the basic tensegrity spine, removing a pair of soft members, and shifting the attachment position of one end of the soft members, the bistable tensegrity joint can be achieved. The development of a tensegrity joint consists of the members with weighing about 17 grams, which immediately performs rapid flexion movements against the slightest stimulus.

Soft robots, made of elastomers and gels tend to easily break, punctured, or torn by contact with sharp and thin objects. To deal with this problem, we had proposed a robotic blood vessel mechanism that has a self-healing function by inserting liquid-filled blood vessels in the body. their bodies themselves. The liquid flows out and is cured which makes the would heal when the body breaks. In this research, we have improved the healing performance by attaching a liquid-absorbent material on the robot surface. Through experiment, it has confirmed that the self-healing ability can be improved by attaching the absorbent material.

Elite sprinters show the bimodal vertical ground reaction force in running denoted as third-order Fourier series. To clarify this mechanism, we focused on elastic organs in the human upper body and used two wobbling masses elastically supported in the trunk. In this study, to reveal the effect of the wobbling mass and its mechanism from a dynamical viewpoint, we investigated the hopping locomotion of a simple model, which consists of two wobbling masses, and numerically searched limit cycles of the model. From the normal mode analysis of the solutions, the generation mechanism of the bimodal and unimodal ground reaction force is clarified. The results suggested the mechanism under which humans perform extremely high-speed running using bimodal ground reaction force as a result of interaction between the body and wobbling masses.

We are interested in the quick movements of fish, and have developed fish-type robots driven by snap-through buckling aiming to mimic these movements. In our previous research, we developed a fish-type robot using snap-through buckling and wire drive. However, the robot could not swim efficiently because of swimming only by the tail fin. In this paper, we proposed a fish robot with flexible body driven by snap-through buckling and wire drive. After confirming the movement of the proposed mechanism, we developed a waterproof fish robot with the mechanism and carried out swimming experiments. From the results, it was confirmed that the robot was possible to swim smoothly by bending the body flexibly. It was also confirmed that the amplitude of the tail fin increased in proportion to the deflection length, and the swimming speed also increased as the amplitude of the tail fin increased.

PneuFinger, soft robotic finger with flexible exoskeleton is designed and two prototypes with different lengths is made. Grasping experiments using a soft robot gripper of two finger type with PneuFingers applied was conducted．In the experiments, four objects with different properties (textile, small tomato, circular saw, and detergent container) was successfully grasped and a maximum payload of 1 kg was achieved.

Continuum robots that can reach objects through narrow and winding paths by their flexibility and compliance have shown promise for inspection, assembly, and pickup tasks in unstructured environments. High flexibility is a considerable advantage but reduces payload. Our goal of this study is to build a flexible robot arm that can pick up a heavy object. The use of a constant load spring with anisotropic stiffness increases the payload. We investigated the stiffness of the proposed robot in the direction of the center of gravity.

If we can realize a flexibly deformable robot that imitates the form and function of organisms in nature that generate motion by flexibly deforming their own form, it will be possible to move in a form that was previously impossible. In addition, if the robot has a plane shape, it can move on uneven terrain without destroying the terrain by distributing the pressure on the ground even in dangerous places where the foothold collapses. However, in order to transport materials with a planar body, it is considered necessary to have a structure that does not require vertical movement of the body, but can operate only by lateral movement. In this study, we devised a planar flexible moving body that can carry objects, and developed its motion mechanism.

Focusing on the highly maneuverable underwater motions unique to fishes, such as rapid turning and acceleration, we have studied fish type robots using snap-through buckling. In this paper, frequency characteristics of snap-through buckling in water are measured in order to provide a quantitative index for the design of a fish type robot using snap-through buckling. We proposed a mechanism for generating continuous and high frequency snap-through buckling using a scotch yoke mechanism, and developed an experimental system using the mechanism. The motion of the tail fin in water due to snap-through buckling was measured using the elastic body width and deflection length as parameters, and Bode plots were created for each condition. From the experimental results, it was quantitatively shown that there was a frequency characteristic of decreasing gain in the high-frequency range when snap-through buckling occurred in water. The frequency where the gain begins to decrease was approximated as the breaking point frequency, and it was found that the breaking point frequency was higher for larger elastic bodies and lower for larger deflection lengths.

In order to move on uneven ground, control with sensor such as a force sensor is necessary. Thus, we propose a soft continuum leg robot. The continuum legs passively change the shape and improve the ground adaptability without using the sensor. Moreover, the development of the continuum legs referred to brittle star. Brittle star is a moving creature that uses thin, long and flexible legs. It has a high step climbing ability and omnidirectional movement ability with five legs interlocked. These abilities are useful for mobile robots. In this paper, we investigate the effective spirals for the DOF reduction of the continuum leg with reference to brittle star, and calculate the design parameters that can express the target helix.

We have developed an impulsive motion generator mimicking Alpheus brevicristatus. Alpheus brevicristatus can close their claw at the speed that generates plasma shock waves in water. We employ their unique joint structure called the cocking slip joint and design an artificial actuation mechanism with a passive elastic element to induce the impulsive motion through storing and releasing the elastic energy; rather than adopting their musculoskeletal structure as it is. Our design approach allows the developed device to generate the impulsive motion repeatedly by a single actuator with a small actuation force compared with the stored elastic energy, which is verified through experiments.

We have developed a actuator composed of quasi-DD motor and gravity compensation mechanism. In this paper, we have developed a compliant 3DOF robot arm with the actuator and conducted evaluation experiments of the robot arm. It showed the effectiveness of the actuator and the compliant robot arm.

The purpose of this research is to investigate the effect of the difference in the activity time phase of TSA on the smoothness of the movement of the mechanism when the drive number change control is applied to the distributed cooperative drive soft-actuator system (DCD-SAS) that imitates human muscles. The drive timing of each TSA is changed to 0, 10, 50, 100 ms, and the contraction speed waveform of a single TSA is compared with the contraction speed waveform of the entire mechanism when multiple TSAs are driven with a time difference. However, the drive timing close to the shape of the contraction velocity waveform of a single unit was obtained as a smooth movement. As a result, it was clarified that the smoothest movement was achieved with a time difference of 10 ms.

It was confirmed that the torque transmission of the rotary clutch using the fracture and phase change of the low melting point metal is larger than that calculated from the breaking strength of the low melting point metal. Therefore, in this study, we focus on the frictional force inside the mechanism and consider the effect on the transmission force. As a result of the experiment, it was found that the transmissible torque of friction is 12 kgf cm or more, and it was also confirmed that the transmissible torque decreased when the torque transmission due to the dynamic friction force was continued. In the future, we aim to carry out embedded experiments in robots.

Many rescue robots have been developed to search for survivors under the rubble in disasters such as earthquakes and tsunamis, and to search for survivors in unexplored areas. Among them, robots with amphibious capability and rough terrain traversing capability are useful to operate in various environments. In this study, we developed a multi-legged walking robot consisting of multiple segments connected by passive body segments with swimming capability. The walking and swimming capability of the robot was verified using the developed robot. As a result, it was found that the developed robot can move using the existing walking method and the proposed swimming method. Furthermore, we found that the high motion performance was produced by the large swing angle and the short deflection period in both walking and swimming.

In this paper, the backdrivability of geared motors using existing reduction gears is clarified by preliminary experiments. Based on the results, new low-friction geared motors using cycloidal drives of 20 reduction ratio and a 4-DOF robotic arm with them are developed. The backlash and backdrive-torque resulted approximately 1 arcmin and approximtely 1 Nm. It was confirmed that the joint stiffness can be varied only by adjusting feedback gains.

Because the passive dynamical mechanism is supported to play an important role in locomotion, in our laboratory, we are practicing this in the development of both biped walking and running robot. In our laboratory, we aim to develop a biped running robot in a more stable state. In this study, we focused on the human foot and leg mechanism, and we improved the foot and changed Soleus muscle pneumatic drive to gastrocnemius pneumatic drive. In this paper, we report that we realized human-like leg motion and got insights into how to generate human-like ground reaction force.

We propose the use of a flow sensor as a method for measuring the position of an air-driven system. It has the advantages of non-contact and remote measurement for air driven systems, and is expected to be used for robot hands. In this report, we experimentally demonstrate the performance of the flow sensor as a position measurement sensor.

Omnidirectional Mobile Robots(OMRs) are known to be holonomic systems and most dynamic models of OMRs do not assume the influence of a load that is loaded on OMRs. In this paper, we deal with the problem of modeling and simulation of motion of a OMR where the robot are carrying a load. First of all, the kinematic model and the dynamic model taking account of a load are derived. We assume that a loaded object is fixed on the OMR and both position of center of gravity of robot and object are not coinciding. The simulation shows that the controller which takes account of a load on the OMR can give better tracking performance. This work shows that the importance of influence from a load on the OMR and suggests that tracking performance can be better with the dynamic model which taking account of a load.

In recent years, there has been a growing need for robotic inspection of aging pipelines. In our previous works, various in-pipe inspection robots have been developed. However, experiments revealed that the robot could travel only 15 m long with 13 bends. The key factor of this travel performance is that the frictional force between the power and communication cable and the inner wall of the pipe. This paper proposes a middle drive unit located between the robot and the commander computer for reduction of the friction. The dimension parameters of the unit for passive rotation in a bent pipe were determined by geometric analysis and verified by experiments.

The differential gear installed in automobile realizes stable driving and turning by evenly distributing the input torque by differential drive. Meanwhile, ambulatory animals often display gait patterns according to their moving speed and move efficiently with a constant rhythm. As an example, a crow generates walking at low speeds and transitions to hopping at high speeds. The factors that generate the gait pattern have not yet been elucidated. However, it was considered that if the leg driving force was not equalized, it could lead to a fall. In this study, we manufactured a one-input, two-output underactuated bipod robot with a differential gear in the powertrain, and showed that the leg driving force distribution can generate a rhythmic gait pattern.

This paper presents a wheeled V-shaped in-pipe robot that two outputs of the wheel-shaft and the roll-joint are driven by only a single actuator. This underactuation is generated by a simple miter gear and a one-way clutch mechanism. By using differential mechanism of the miter gear and one-way clutch, the proposed joint enables a hemispherical wheel to switch between a pitch rotation (wheel drive) and a roll revolution by changing the rotational direction of the motor.

In recent years, aging of pipelines is becoming a critical issue faced by human beings. However, some pipes lack information such as length and location of bends, which hinders the replacement and removal of pipes. Therefore, it is necessary to create a map of the pipeline. In this paper, a method of constructing a three-dimensional pipe map based on forward kinematics by installing a wheel encoder and a gyro sensor in the towed unit of a robot.

Today, the lack of sleep is becoming a problem in Japan. The main reasons for the lack of sleep are changes in the work environment and using a smartphone for a long time. For these reasons, about one in three people complain of the lack of sleep. The lack of sleep affects the body leading to the unproductivity at work. The solution to the lack of sleep is to get enough sleep. But it is difficult method to use in today’s busy society. The purpose of this study is to develop a device that improves sleep quality by controlling the depth of sleep intentionally.

Stability while walking is essential as accidents may lead to severe injuries. In this study, we calculated the margin of stability (MoS) and maximum Lyapunov exponent (λ_s), the two prominent stability indices of walking, using a gait database of 300 people with 1.5 strides. Thus far, the relationship between these indices and other gait parameters including joint angles has not been investigated for such a large participant pool. Therefore, we determined the relationship between these stability indices and gait parameters by using multiple regression analysis. The results showed that the MoS was dominated by walking speed in the forward direction and associated with various joint angles in the lateral direction. Conversely, no relationship was identified betweenλ_s and gait parameters. Although the MoS and λ_s represent certain aspects of gait stability, they are either independent or associated with only a part of gait parameters. Thus, the feature of gait motion represented by λ_s does not rely directly on the gait parameters. λ_s is not expected to be easily improved by modifying a specific gait parameter.

In this study, Kinesthetic Illusion is defined as the perception that the body has been moved even though the body has not been moved. We developed a system that generates Kinesthetic Illusion by combining forced body movements by electric stimuli and video images of body movements. Using this system, we investigated the effects of the type of electrical stimuli and video stimuli on the Kinesthetic Illusion. As a result, it was found that the motion illusion was easily generated when the electric stimulus and the video stimulus were the same type and when the electric stimulus was strong.

Measurement technology of the human body mechanical properties during the walking motion can be used for evaluation of locomotion skills. We develop the bone conducted-sound sensing system which uses propagated vibration in the body to estimate the mechanical properties of the human body. During the measurement, the vibration generated by the body becomes noise. In this paper, we report the effect of the devices for attaching the sensor to the human body on the measurement of the vibration.

In order to prevent falls in the elderly, it is important to collect and analyze data for the standing motion. This study proposes the measurement and diagnosis system for grasping the decline in athletic ability due to aging of the elderly. And it is planed to install the system at toilet to collect the human standing motion in daily life. As an initial stage for constructing a system, Kinect V2 and Wii board are applied to measure the standing motion of 10 young subject persons from the chair / toilet under three conditions in this report. The experiment results show a significant difference in the standing time at the case of standing from the toilets with different heights under the two conditions. In addition, there was no significant difference in the ratio of the maximum floor reaction force under the same conditions. As the future work, it is necessary to collect data on standing motions for middle-aged and elderly people other than young people.

The necessity of stress estimation by non-contact method has been increased in recent year, such as stress assessment during vehicle driving or remote environment. It is expected for the methodology with non-contact, non-invasive to reduce not only the burden of subject people but also noise of measurement. In this study, basic experiment of a stress estimation method using facial image and heartrate have been conducted under the condition with psychological work load. And comparison results between interval analysis of heartrate and changes in green color component of facial color were analyzed. In addition, validity of experimental setup for measurement devices and pattern of psychological work load have been discussed for future developmental research.

Recently, VR(virtual reality) technology is widely used for game, amusement and simulation of special experiences etc. by using HMD(Head Mounted Display). High quality of VR content is also needed to increase the reality of experience. However, it also requires to maintain the balance between huge amount of data and its processing cost. As a result, imbalance of them makes the decreasing of frame rate of the VR movie and its smoothness lost. This smoothness lost is called jerkiness and the its relations with motion sickness have been examined by the movie on the flat display in the previous studies. In this study, the experiments by using HMD were conducted to investigate the jerkiness perceptual intensity under the several conditions of the decreasing of frame rate. In this report, the subjective evaluation results by questionnaire survey with subject people have been discussed.

In recent years, there has been a remarkable development in human detection technology. Among them, Haar-like feature is known as one of the excellent methods. However, depending on the usage environment, this method may not work well in some cases. Therefore, in this paper, we describe a method for distinguishing between people and cars at a construction site. The distinction is done by measuring the angle distribution from the motion of a person and a car by Optical Flow, and letting the Neural Network learn the difference in the angle distribution. The conditions of the person were working, moving in a half-sitting posture, and kicking a cart.

This study proposes an input interface which is capable of multi Degrees of Freedom (multi-DoF) control for the device including mouse cursor and a robot by using oral movement of user.The typical hands-free interfaces such as eye tracking system which control multi-DoF are limited at the point of involuntary contorol. The intraoral movements have precise and versatile movements.The interface consists of an intraoral and an extraoral link. The intraoral link includes a 3DoF joystick for detecting fine and discrete inputs such as pressing buttons and the extraoral link includes a 9DoF IMU for capturing gross and continuous movements of the interface such as sway and rotation. In this paper, we introduce the design of orally-manipulated input interface, the method of multi-DoF measurement, and the performance evaluation in practical control applications and biting detection.

Teamwork was evaluated through a questionnaire survey after the experiment. However, there are some problems such as it is subjective and not in real time. In addition, there are few examples of team composition based on physical cooperative work results. In CFO, which focuses on the difference between cooperative task and solo task, evaluation can be done in real time. However, teamwork evaluation by CFO requires experiments for each pair. Therefore, we attempt to generate a model that takes into account the interaction of forces. The generation of the cooperative work model was suggested but lacked accuracy. Therefore, we construct a direct-following task suitable for analyzing cooperative tasks, and propose a method for estimating CFO focusing on the difference of forces between solo and cooperative tasks. The proposed method achieves more detailed analysis of the cooperative work.

Establishing fall prediction prevention methods is always essential for the elderly. In the conventional research, the user receives a physical stimulus from the outside, and the sensory organs measure the internal state of the user by intervening an index. In this research, we propose a method of generating a virtual centrifugal force by passing through a VR curve, and measure the internal state caused by the user with an image that does not give a sense of discomfort in the VR space. Therefore, for the purpose of research, the amount of head sway caused by the visual stimulation is measured and analyzed, and based on the results, the effect on human balance is evaluated.