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To those thinking of joining us, ASI

Research

Policy

We are going to create a new interdisciplinary field "Safety Intelligence" through research and development of human-support machines that contribute to our sustainable society. Safety Intelligence is the achievement of human safety by innovative intelligent machines.

Outline.

Research Projects

Safety of wearable robot

Development of Lower-limb Dummy for Safety Assessment of Human Wearable Robot
Study about the reduction of fall risk induced by a wearable robot
Development of a new safety validation and verification method for wounds resulting from the use of Lower-limb power assist robots

Human factor

Modeling of Human Avoidance Action Characteristics for Estimating Avoidability of Harm to Eyes from Robots
Human-Robot Collision Simulation Taking Human Avoidance Motions into Consideration
Experiments and Modeling of Collision of Sharp Mechanical Hazards against Eye for Estimation of Injury Severity

Clinical robotics

Wearable dummy for simmulating joint disorders
A study on an assistance in preventing the elderly from falling by mobile robots
Fall Risk Reduction for the Elderly Using Mobile Robots Based on the Deep Reinforcement Learning

Haptics

Haptic invitation: why do we feel inclined to touch?
Vibrotactile texture display
Vibrotactile feedback model for fragile object & foot-step display
Perceptual dimensions of tactile textures
Human sensory-motor loop: Amplified finger-pad defromation enhances tracing movement
Wearable dummy for simmulating joint disorders
Sensory integration of cutaneous and proprioceptive force cues

Motion and vibration control

Base-Extension Separation Mechanism for Landing Shock Response Control of Lunar/Planetary Exploration Spacecraft
Landing Response Control of Lunar/Planetary Exploration Spacecraft by Means of Non-Flying-Type MEID Mechanism
Shock Response Control Based on Two-Mass-Spring System Dynamics
Study on Motion Control for Connection and Cooperation of Plural Mechanical Systems
Study on Wireless Controlled Systems for Assist Carts

Wearable robot

Development of Lower-limb Dummy for Safety Assessment of Human Wearable Robot

Wearable power assist robots are expected to improve quality of life of people who have disabilities and need care. In addition, they probably can increase productivity of workers. However, careful concern of safety is required because these robots are directly equipped to human body.

In this research, we focus on burden applied to a human body by a wearable robot to investigate the method of safety assessment of wearable robot. Therefore, the lower-limb dummy to mimic characteristics of human body is developed.

Reference

Study about the reduction of fall risk induced by a wearable robot

A wearable power assist robot will increase the daily living area of elders and disabled people through gait assist. Therefore, development of such power assist robots progresses for aging society. However, they induce fall of wearer in case the motion of the robot and the wearer is mismatched.

The aim of this research is to develop assist algorithms and counter measures against fall risk induced by a wearable robot in various situations. For this purpose, experiments using a wearable power assist robot which is developed in our lab and the simulation are used.

References [1], [2]
     

Development of a new safety validation and verification method for wounds resulting from the use of Lower-limb power assist robots

Wearable power assist robots are expected to improve quality of life of those disabled or aged people who need more care during their daily activities. However, these robots are directly equipped to human body so that there are risks generating wounds such as blister and abrasions on contact point on human body.

In this research, we develop the validation and verification method for wounds resulting from the use of power assist robots

Reference

Human factor

Psychological Experiments on Avoidance Action Characteristics for Estimating Avoidability of Harm to Eyes from Robots

A human-robot cooperative working system is desired at production sites. To realize such system, the worker's risk needs to be estimated exactly.

We have conducted psychological experiments for investigating human avoidance-action characteristics during a situation in which the end-effector tip of a robot suddenly approaches the eyes of a human.

References [1], [2]

Human-Robot Collision Simulation Taking Human Avoidance Motions into Consideration

In designing production systems, the avoidability, which is the possibility to avoid or limit harm, tends to be neglected or intuitively estimated. Hence, the risk of human-robot coexistence systems is not reasonably estimated.

We propose a human-robot collision simulator using human motions observed in psychological experiments. Based on the simulation results, we can estimate safe conditions in a human-robot coexistence system.

Reference

Experiments on Collision of Sharp Mechanical Hazards against Eye for Estimation of Injury Severity

The study objective is to exactly estimate human risk with the aim of realizing human-robot cooperative working systems. We assume that the sharp end effector of a robot approaches the eye of a human. We have conducted eye collision experiments taking into consideration human avoidance/mitigation actions such as turning his/her face and have investigated the injury severity.

Reference

Clinical robotics

Wearable dummy to simulate joint impairments for trainings of PTs

Physical therapists master manual examination techniques for testing impaired motor functions. However, during educational periods, oppotunities to learn various symptoms are limited for trainees.

We developed a wearable robotic dummy joint to simulate disordered joint resistances for supporting physical therapists to learn such techniques. The wearable dummy allows the trainees to experience realistic human joint behaviors and other human likeliness including characteristic bones, skins, and limb weight. Currently, the dummy robot can simulate symptoms such as contracture, spasticity, limitations of motion ranges, crepitus, and etc.

Reference [1], [2]

A study on an assistance in preventing the elderly from falling by mobile robots

In order to reduce the increasing rate of accidents concerning elderly people at the age of 75 years or older, this paper discusses a tendency of accidents, its main factors, and the triggers of the factors by analyzing statistical data of the accidents. This study proposes a new method to reduce the risks of the accidents by introducing a mobile robot to detect the associated changing factors. We set a hypothesis of a law for the occurrence of accidents. The hypothesis is ”An accident occurs under changing factors.” As an example, the paper describes a consideration of a mobile robot for an assist in preventing the elderly from slipping to fall. It is realized by detecting liquid on the floor as one of the changing factors, and assess the feasibility toward verification of the hypothesis.

Reference

Fall Risk Reduction for the Elderly Using Mobile Robots Based on the Deep Reinforcement Learning

This paper proposes apply a deep reinforcement learning to control mobile assistant robots and reduce slip-induced fall risks for the elderly, in addition to use a deep convolutional neural network to analyze fall risks.

Reference

Haptics

Haptic invitation: why do we feel inclined to touch?

Some textures and materials invite human touch in daily life. In this study, we are investigating the mechanism of such haptic invitation and developping methods for using materials that frequently invite human touch.

We devised a technique for describing degrees of haptic invitation by linear combinations of the visual and sensory properties of materials. In addition, we revealed that textural prominences invited human touch motions, and different types of prominence determine different types of invited motions. Therefore, we interpret the haptic invitation of materials as a phenomenon that prominent textures of different materials encourage us to feel them using appropriate touch motions.

References [1], [2]

Vibrotactile texture displays for virtual materials

A vibrotactile texture display produces virtual textures by applying vibratory or mechanical stimuli to finger pads. Such texture displays are expected to be installed on mobile terminals. In this study, we are developing 1) techniques to improve the quality of textures, 2) lossy-data compression algorithms for online haptic content, 3) theories to match or compare textures to mechanical stimuli, and 4) stimulus patterns to produce tactile sensations such as softness and friction percepts that are generally considered difficult for vibrotactile displays.

References [1], [2], [3]

Sensory-motor loop: Amplified shear deformation of finger pad increases tracing movements

Human sensory inputs and motor outputs mutually affect each other. We pursue the idea that a tactile interface can influence human motor outputs by intervening in sensory-motor relationships. This study focuses on the shear deformation of a finger pad during tracing movements. Using a tactile interface, we amplified the finger pad's skin stretch, and found that such amplification enhances human hand movements based on the principles of sensory-motor loop of haptic tasks.

Reference

Active foot-setp display for fragile structures

This virtual reality interface presents the sense of foot steps on fragile structures such as fallen leaves and frost. In our daily lives, the vibratory stimuli given to foot soles depend on the types of broken structures and active foot step motions. Nevertheless, we easily recognize the stepped structures with no regard to the foot speeds. To capture these perceptual features, our device synthesizes the sole stimuli according to the active foot speed on real-time based on on our vibrotactile spectrum synthesis techniques.

Reference

Psychophysical dimensions of tactile textures

We have many adjective words that can be used for expressing textures of material surfaces. What is the dimensional structure of the space of such adjective words and human perception?

We have specified the perceptual structure of psychophysical perception of textures. As a result, it was concluded that the reasonable psychophysical dimensions are roughness/smoothness, hardness/softness, warmness/coolness, and friction (stickiness/slipperiness). Roughness percepts can be further categolized into dimensions; they are macro (bulky/flat) and fine (rough/smooth) roughness. Hence, these are principle fine dimensions.

Reference

Sensory integration of cutaneous and proprioceptive force cues

Our sensation is produced by the ensemble of some perceptual channels. In the case of a percept of force applied to a finger tip, the sensation is the integration of proprioceptive and cutaneous cues. It is important to specify the contribution of each channel for developing haptic interfaces. For example, it is effectual to feedback tiny forces to human skins because the skin in charge of the percepts of small forces. On the other hand, to feedback large forces greater than several newtons to humans, proprioceptive cues are dominant, and cutaneous cues can be ignored. For the forces around a few newtows, we have to pay a sufficient care because both cues play major roles in force perceptions.

We experimentally specified the contribution ratios of proprioceptive and cutaneous channels for the force applied to finger tip.

Reference

Motion and vibration control

Base-Extension Separation Mechanism for Landing Shock Response Control of Lunar/Planetary Exploration Spacecraft

We invented a novel landing mechanism called "Base-Extension Separation Mechanism (BESM)", which achieves soft landing by means of energy transfer. In addition, we proposed additional attachment called "Telescopic Gear (TG)", which achieves vertical operation of the BESM for uneven terrains. We are developing these technologies to further improve the BESM and to apply the BESM for actual lander missions.

Naoaki SAEKI, Susumu HARA and Masatsugu OTSUKI, Application of Telescopic Gear to Lunar/Planetary Exploration Spacecraft with Base-Extension Separation Mechanism, Proceedings of the 65th International Astronautical Congress (IAC 2014), IAC-14-D2.3.9, Toronto, Canada, 2014-9.
   
(Left figure) BESM structure and its operating principle

(Right figure) Structure of the BESM with TG and its operating principle

Landing Response Control of Lunar/Planetary Exploration Spacecraft by Means of Non-Flying-Type MEID Mechanism

We proposed a novel landing mechanism called "Non-Flying-Type MEID (NFMEID, MEID: Momentum Exchange Impact Damper)", which can reduce momentum of the spacecraft and realize the soft landing, based on the principle of momentum exchange. Unlike in the conventional MEID mechanisms which shoot the extra mass for momentum exchange, the NFMEID mechanism can change the direction of the influence of shock and realize momentum exchange in the system including the spacecraft. Therefore, the NFMEID mechanism minimizes the shot mass’ harmful effects such as the pollution of lunar/planetary surface and its collision with the spacecraft. Furthermore, the NFMEID may be applied to the shock response control of the general mechanical structures as well as the spacecraft.

Susumu HARA, Shintaro MATSUI, Naoaki SAEKI and Masatsugu OTSUKI, Landing Response Control of Lunar/Planetary Exploration Spacecraft by Means of Non-Flying-Type MEID Mechanism, Proceedings of the JSME Tokai Branch 64th Annual Meeting (Tokai Engineering Complex 2015, TEC15), No. 153-1, 275, Kasugai, Japan, 2015-3, (in Japanese).

The scheme of NFMEID and its operating principle

Shock Response Control Based on Two-Mass-Spring System Dynamics

We aim the generalization of a shock response control using MEID mechanism based on momentum exchange principle. Lunar exploration spacecraft landing problem, which is an important application of the MEID, needs to suppress a rotational motion induced by a landing shock to prevent tripping. A two-mass-spring system model, which corresponds to a fundamental model of a MEID mechanism including the rotational motion, is studied to generalize a theory and derive the optimal design methodology which controls shock responses by MEIDs.

Yohei KUSHIDA and Susumu HARA, Consideration of Momentum Exchange of 2-Mass-Spring-System Which is Separated by External Input, Proceedings of the 15th SICE System Integration Division Conference (SI 2014), pp. 2425-2428, Tokyo, Japan, 2014-12, (in Japanese), (Best Presentation Award).

Yohei KUSHIDA and Susumu HARA, Dynamics of a Two-Mass-Spring System Which Is Separated by External Input, Proceedings of the 2015 IEEE International Conference on Mechatronics (ICM 2015), pp. 472-477, Nagoya, Japan, 2015-3.

(Upper figure) Schematic figure of MEID rotational motion which is induced by a shock

(Lower figure) A two-mass-spring system model

Study on Motion Control for Connection and Cooperation of Plural Mechanical Systems

In order to improve the efficiency of works by power-assisted systems, we are aiming to develop a control system design method which realizes connection and cooperation of plural mechanical systems. Updating final-state controller is anew introduced and smooth connection is realized. The effectiveness of the control system is verified by experiments and simulations.

The figure on the upper shows the connected two power assist carts. This research also realizes tumble prevention of conveyed objects by means of a linear actuator installed on each conveying stage.

Takahito YOSHIURA and Susumu HARA, Proposal of Updating Final-State Control and Its Application to a Connection Control Problem, Proceedings of the 13th International Workshop on Advanced Motion Control (AMC 2014), pp. 681-686, Yokohama, Japan, 2014-3.
   Connected power assist carts.
  Cooperative control.

Study on Wireless Controlled Systems for Assist Carts

For used by elderly people in household, we proposed a novel remote control system of assist carts with Wi-Fi. The controlled object's picture and model in this study are shown in upper figures. The control object is made of silver cart on the market. Lower figure shows the concept of this study. To put a high specification computer out of the assist cart enables us to decrease the mass and cost of cart. In addition, this configuration enables the high specification computer to monitor the states of assist cart users.

Susumu HARA, Kenta SUZUKI, Yoji YAMADA and Hiroki YOSHIMURA, Investigation of Wireless Control Systems for Assist Carts, Proceedings of the JSME Conference on Robotics and Mechatronics (ROBOMECH 2015) No.15-2, 2P1-J08, Kyoto, Japan, 2015-5, (in Japanese).

(Upper figure) Control object and its model
(Lower figure) Concept of this study