Walking Assistant Robot Research Articles

Geriatric Walk Assist Robot - Design, Analysis and Implementation of a Modular Lower Limb Exoskeleton Robot

Among the problems of major concern faced by the geriatric community the fore most is considered to be: “as we grow older it gets difficult to walk”. As they lose their strength to withstand their weight they become weak to walk on their own. Through this project a design is proposed for an assistive modular lower limb exoskeleton robot to enable aged people to walk on their own. The design is mainly based on the amplification of the pressure applied on the thighs and ankles of the legs and these pressures are used to move the legs of the robot which support the legs of the user. Since the user is capable of generating a minimum pressure on their own the working of the gait pattern is mainly based on the movement of knee and ankle, and so only the knee and the ankle are considered in this design. Another reason is that the major weight of the body acts on the knee and the foot while walking. The working of the robot is mainly based on the layered control algorithm embedded on the microcontroller acting through the sensors and actuators. Pressure sensors are used to measure the applied pressure and electrical actuators are used due to their lesser weight. Based on the experimental results obtained with the working robot the design would be fine-tuned for optimized performance.

搭乗者の動作を検知して稼動する歩行支援ロボットに関する研究

搭乗者の動作を検知して稼動する歩行支援ロボットに関する研究

歩行アシストロボットを用いた回復期脳卒中患者に対する歩行練習の影響

歩行アシストロボットを用いた回復期脳卒中患者に対する歩行練習の影響

스테레오 카메라를 이용한 지능형 보행보조로봇의 개발

용자 보행 추종 성능을 실험적으로 검증하였다. Abstract: This paper describes the development of a walking assistive robot for effective self-rehabilitation for elderly people facing an inconvenience in walking. The main features of the developed robot are enhanced safety and mobility using the baby walker and electric wheelchair mechanisms and an accurate walking tracking control algorithm using potentiometers and stereo cameras. Specifically, a pelvis supporter is designed to prevent the user from falling down and reduce the burden on their legs, and electric motors are used for easy locomotion with low effort. Next, the walking intention and direction of the user are automatically recognized by using potentiometers attached at the pelvis supporter so that the robot can track the user, and the rapidity and accuracy of the tracking were increased by applying a lower-body motion analysis algorithm with stereo cameras. Finally, the user-tracking performance of the developed robot was experimentally verified through stepwise walking assistance experiments.

Pattern generation and control of a double pendulum using a nonlinear oscillator

Prior to developing the wearable walking assistant robot that supports walking for hemiplegia patients, a neural oscillator, a type of CPG (central pattern generation), was applied to 2-DOF double pendulum, which can replace the leg of a robot. The walking pattern generation method was proposed using the gait pattern of the non-affected side of hemiplegia patients. Because it is difficult for hemiplegia patients to distinguish the intended action signal of the patient wearing a robot on their affected side, we had to utilize a limited amount of information to get the maximum effect. We needed an effective solution for robot control in an outside environment where many unknown disturbances exist. In order to deal with these two problems, we used a nonlinear oscillator with a double pendulum as a test bed to explore the possibility of producing a robot walking pattern.

A Walking-Assistant Robot Controlled by Tactile-Slip Sensation

A walking-assistant robot guided by the intention and power-driven is presented, its purpose is to provide physical support and walking assistance for the elderly to meet their needs of walking autonomy, friendliness, and maintaining the ability of walking and taking care of themselves. Tactile and slip sensor is selected as the human interface to perceive the users walking intent, and the sensor is also used to detect the user's slip trend. And the paper researches the feature representation and extraction method of tactile and slip signal for driving control pattern recognition. An improved classification and identification method combining K-means in clustering and K-nearest neighbor algorithm in classification is proposed. The paper introduces the overall design schemes of tactile and slip drive control system of walking-assistant robot, perception system, motion control system. Finally the feasibility and effectiveness of the entire system are verified by experiment.

Walk-Assist Robot: A Novel Approach to Gain Selection of a Braking Controller Using Differential Flatness

With increasing populations of the elderly in our society, robot technology will play an important role in providing functional mobility to humans. From the perspective of human safety, it is desirable that controllers for walk-assist robots be dissipative, i.e., the energy is supplied from the human to the walker, while the controller modulates this energy. The simplest form of a dissipating controller is a brake, where resistive torques are applied to the wheels proportional to their speeds. The fundamental question that we ask in this brief is how to modulate these proportional gains over time for the two wheels so that the walker can perform point-to-point motions. The unique contribution of this brief is a novel way in which the theory of differential flatness is used to plan the trajectory of these braking gains. Since the user input forces are not known a priori , the trajectory of the braking gain is computed iteratively during the motion. Simulation and experimental results show that the walk-assist robot, along with the structure of this proposed control scheme, can guide the user to reach the goal.

노약자들을 위한 인체공학적 보행 보조 로봇의 개발

This paper describes the development of a novel walking assistance robot for the elderly and infirm. In the case of simple walking assistance devices, the walking safety and effectiveness are somewhat low; hence, caregivers are frequently required. The walking assistance robot developed in this research is capable of securely and conveniently assisting a walking user by using electric motors and various devices without a caregiver. The main features include the following. First, the walking safety is improved by using a pelvis supporter, and the robot is able to follow the user effectively by means of ergonomic motion sensors and electric powered wheels. Second, it is possible to adjust the load applied to the lower body by adjusting the height of the pelvis supporter. Finally, it is possible to inform the approximate distance and direction of any obstacle around the robot using the sounds and vibrations for the blind and the hearing impaired. The performance of the developed walking assistance robot was successfully verified using a walking assistance test in a narrow-corridor environment.

Active and Passive Control of Walk-Assist Robot for Outdoor Guidance

In the currently aging society, walk-assist robots can play an important role in improving the activities of daily living of the elderly. In this paper, we propose a robot walking helper with both passive and active control modes for guidance. From the perspective of human safety, the passive mode adopts a braking control law on the wheels to differentially steer the vehicle. However, if the user walks uphill in the outdoor environment, external forces need to be supplied to the human-walker system. In this paper, we add an active mode to guide the user in situations where the passive control mode alone with user-applied forces is not adequate for guidance. The theory of differential flatness is used to plan the trajectory of control gains within the proposed scheme of the controller. Since the user input force and slope angle of the path are not known a priori , the theory of model predictive control is used to periodically compute the trajectory of these control gains. The simulation and experiment results show that the walk-assist robot, along with the structure of this proposed control scheme, can guide the user to a goal on a slope effectively.

횡단경사면에서 지능형 보행보조로봇의 직진성 향상 방안 연구

본 논문은 지능형 보행보조로봇이 횡단경사면주행에 있어 직진성 향상 알고리즘을 제안한다. 보행보조로봇은 횡단경사면주행시 로봇의 무게와 경사도에 의해 발생되어지는 회전모멘트의 영향을 받아 경로 이탈을 하게 된다. 이를 보정하기 위해 사용자가 입력하는 목표 회전각속도와 로봇의 회전각속도와의 비교를 통해 각 구동축에 가중치를 인가하는 알고리즘을 적용하였다. 제안한 보정 제어기를 실＼제 보행보조로봇에 적용한 결과 횡단경사면 이동시 Yaw 축 이탈거리는 무보정 실험의 경우 발산하지만 Yaw 보정 알고리즘을 적용하였을 경우에는 이탈거리가 최대 20cm 이내로 안정적인 주행을 하는 것을 확인할 수 있었으며, 이탈거리 변화율 또한 300cm 이후 안정화되어 더 이상의 변화가 발생하지 않는 것을 확인할 수 있었다.

Motion Analysis and Experiments on the Standing-Up Mechanism of Walking Assistance Robot

The standing-up mechanism of a multifunction walking assistance robot is developed to help the patients with lower limb diseases to stand-up normally, and only one actuator is used for motion control. The normal people's standing-up kinematics of hip, knee, ankle joints are obtained by an information measurement system, which is composed of a joint angle measuring system, a metronome and the dSPACE semi-physical simulation platform. Based on that information, the kinematic simulation of normal people's standing-up is analyzed by SimMechanics. By immigrating the hip's motion, the motion of the end-effector of the standing-up mechanism is designed. In human experiment, volunteers can stand up from sitting with the help of the prototype of walking assistance robot.

Motion control of walking assistant robot based on comfort

– A walking assistant robot can help elderly people walk around independently, which could improve the life quality of the elderly and benefit our aging society. Ensuring the elderly person's walking comfort with such a robot is very important. At present, the majority of walking assistant robot research does not focus on this field. The purpose of this paper is to examine the requirements of comfortable walking and outline the design of a motion control algorithm for a walking assistant robot, Walkmate III, based on comfort., – During walking, the walking assistant robot should be able to capture the intent of user, guide the user and move at the same pace as the user. Usually, force or haptic interface is used to detect the user's walking intention. The motion control system then transforms the forces applied by the user into the robot's motion. By surveying the elderly people at a nursing home, the authors find that this transformation is important to the walking comfortableness and should be carefully designed. In this paper, the model of walking assisting process with such kind of walking assistant robot is derived at first. Based on this model, a new motion control algorithm is then designed., – The elderly hoped that, in all topographic conditions, only small forces were needed to drive the walker during walking. Also, good maneuverability was also very important for a walker, to offer the user comfort, which meant the walking assistant robot should be able to respond to the input forces quickly and precisely. Currently widely‐used motion control algorithms cannot satisfy all those requirements. In this paper, a new motion control algorithm is proposed, which can get a fast and precise response to the input forces and the input forces needed to drive the robot are kept at a preferred small level, so that the user will not feel tired during walking. Furthermore, by modifying, force feedback can be realized to improve the comfortableness of walking., – The availability of walking assistant robot with improved walking comfortableness might encourage a wider adoption of robotics in our daily life. It could also benefit our aging society by improving the life quality of the elderly and reducing the pressure deriving from nursing labor shortages., – This paper is of value to engineers and researchers developing walking assistant robots for the elderly people.

기능적 전기 자극에 의한 족관절 근육 반응

This paper deals with an experimental study on the reaction of muscles by functional electrical stimulation(FES) with the design and fabrication of an ankle reaction apparatus. The ankle reaction apparatus consists of a circuit part and a kinematic part, and it monitors reaction time for a particular angle of joint rotation according to FES. The experimental results showed that the change of the ankle rotation angle was linearly proportional to the change of the magnitude of FES. It also showed that the muscle's reaction time was constant no matter how large the magnitude of the stimulus. The results of this paper can be applied to develop an active-type walking-assistance robot.

족관절의 근전도를 이용한 보행운동의 실험적 연구

This paper experimentally deals with the relationship between the ankle electromyogram(EMG) and walking motion in order to activate the ankle joint of a walking-assistance robot for rehabilitation. Based on the anatomical structure and motion pattern of an ankle joint, major muscles were selected for EMG measurements. Surface EMG signals were monitored for several human bodies at various stride distances and stride frequencies. Root-mean-squared magnitude of EMG signals were related with the walking conditions. It appeared that the magnitude of the ankle EMG signal was linearly proportional to the stride distance and stride frequency, and thus to the walking speed.

보행보조 로봇의 운동학적 특성

We developed a walking-assistance robot for walking rehabilitation and assessed the kinematic characteristics of a prototype. The walking-assistance robot is composed of hip, knee, and ankle joints, and each joint is driven by a motor with a decelerator. The equations of angular displacement while walking were derived by theoretically analyzing human locomotion, and the calculated angular displacements were then applied to the robot controller. The output angular displacement of each joint was measured and compared with its input angular displacement in walking experiments on a treadmill at various walking speeds and strides. The differences between the input and output angular displacements are 5.22% for the hip and 2.97% for the knee joints, and it has been confirmed that the walking-assistance robot works well.

The Development of Walking Assistant Robot for the Elderly

The Walking Assistant Robots(WARs) developed by our institute are introduced in this paper. First, three prototypes with different mechanical and control structures are introduced and compared. Then as for the prototypes Ⅲ, its main framework and three important function modules including force sensor based human-machine interaction, Omni-directional vision based tracking and guiding system, and web-based monitoring system are described in detail. The WAR can recognize the user’s intents and execute different assistant functions, such as seating or standing-up assistant, walking assistant, human tracking, location, obstacle detection and avoidance. The application in an elderly care center shows WAR has a perfect and stable performance.

Study on Open Standard Control System of Walking Assistant Robot for the Elderly

To solve the problems of the control system of the working assistant robot for elderly such as lower efficiency and weak complicity. A kind of open architecture, modularity, extensible embedded robot control system is developed. The main contents include: Studied on a rich hardware interface and drivers, function easy-to-modular extended robot development platform. The paper presented the platform features, design concepts and system solutions of the robot control system and gave details of building approaches of the platform. On this basis, the functional modules of the robot were designed and implemented with the modular design approach. Finally a specified working assistant robot was created by loading the completed modules into the control system platform and some experiments were carried out on the robot system. Experiments results show that the system platform can be a convenient and effective way to develop multi-functional working assistant robot for elderly.

P26-24 The cortical oxygenated hemoglobin changes of the brain activity using a walking assistance robot

P26-24 The cortical oxygenated hemoglobin changes of the brain activity using a walking assistance robot

시각장애인을 위한 보행보조 로봇의 개발

For safe walking of the people who are blind, walking assistance robot which can detecting and avoiding the obstacle was investigated. The implemented prototype walking assistance robot consists of a obstacle detecting module, a user interface using acoustic signal and a driving module. The obstacle detecting module uses 6 ultrasonic sensors those located at the front part of the robot can perceive the obstacle which is in 3 meter distances and <TEX>$180^{\circ}$</TEX> degrees. It calculates the distance and degree from the obstacle using TOF (time of flight) method and decides the 3-dimensional location of the obstacle. The obstacle information is delivered to the user using acoustic alarm and guide sound. The robot is designed to avoid by itself when the obstacle is detecting and the user only follows it to safe walking. After the designed robot was implemented, driving and obstacle detecting experiments were carried out. The result showed that the designed walking assistance robot will help the people who are blind to walk around safe.

Walking-support robot system for walking rehabilitation: design and control

An intelligent walking-assistance robot system has been developed to help the elderly or the disabled in rehabilitation programs. From the design viewpoint, several different mechanisms to satisfy the strict requirements for use in a rehabilitation program were considered and studied. A two-wheel mobile mechanism was developed to provide motions to follow the patient's walking trajectory, and also to make the patient follow a specified trajectory. Equations of motion were derived for the unloading control, and a force control algorithm was developed. For motion control of the mobile base, virtual trajectory planning by the B-spline method and PID control were used. Sensing the motion of the patient is performed by a linear potentiometer and a rotating encoder attached to the robot manipulator. The system was tested on patients in hospital and the experimental results are reported.