兼具柔顺与安全的助行机器人运动控制研究

针对助行机器人的柔顺性和安全性问题,基于多传感器系统融合技术,本文提出了一种能够兼具柔顺与安全的助行机器人运动控制方法.首先介绍了助行机器人的机械结构、控制原理以及多传感器系统,然后根据机器人多传感器系统,设计出各传感器相对应的用户意图估计方法,提出了一种基于多传感器融合的助行机器人柔顺运动控制算法.分析用户可能发生的跌倒模式,使用基于卡尔曼滤波（Kalman filter,KF）的序贯概率比检验（Sequential probability ratio test,SPRT）方法和决策函数来判断用户是否会跌倒,并判断处于哪种跌倒模式.最后,通过助行机器人柔顺运动控制实验和用户跌倒检测实验验证了算法的有效性.     

Some aspects of human-friendly control for movement-helping devices

Future welfare models should meet the needs of a large group of aged and disabled people. Present research and technology efforts in this direction are oriented toward the development of highly effective home-installed devices which will provide the user with continuous assistance in different everyday activities. The problems and needs of the elderly and the disabled vary from person to person over a large range, and with many serious requirements. Modern designs for such devices are oriented toward solutions where the user is less engaged in the control process, and the interaction between the device and the user ishuman-friendly, i.e., the devices should possess a high level of intelligence in their controls, actions, and interactions with the user, offering him/her a high level of comfort and functionality. This paper considers a mixed control mode as a better alternative for human-machine interactions for users with great movement disability. Some examples of easy direct control are discussed.     

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.     

Intelligent mobile walking-aids: perception,control and safety

Robot-assisted walking has become a popular research field for helping mobility-limited people to walk more easily. Different from other walking-aid devices (e.g. exoskeletons and prosthesis), intelligent mobile walking-aids (IMWs) are invented for helping the visually impaired or people in need (e.g. the elderly) to walk in daily life. This paper reviews various related literatures on IMWs and dwells on three kinds of perception systems and perception algorithms of IMWs to explain how IMWs understand the user's motion states or tendency. Besides, the control strategies of IMWs under the normal case concerned are classified and compared. The safety measures for preventing the user from abnormal cases (e.g. encountering obstacles, the user's stumbling and falling, faults of IMWs) are introduced in detail as well. The performance of current safety measures for the user's fall detection and prevention has been evaluated and concluded. At the end of the article, the discussion and perspective of IMWs are presented.     

Optimal impedance via model predictive control for robot-aided rehabilitation

This paper proposes an optimal impedance controller for robot-aided rehabilitation of walking, aiming to increase the patient’s activity during the therapy. In an online procedure, the joint torques produced by the patient during the gait is estimated using the generalized momenta-based disturbance observer and the Extended Kalman filter algorithm. At the same time, a model predictive control is performed to obtain the instantaneous optimal stiffness parameters of the robot’s impedance controller, trying to maximize the patient’s active participation by increasing his/her joint torques. In this feasibility study, experiments with a healthy subject, considering a modular lower limb exoskeleton and a set of user’s behaviors, are performed to evaluate the proposed controller. The results show the robot stiffness converges to a value which increases the user’s active participation.     

High path tracking control of an intelligent walking-support robot under time-varying friction and unknown parameters

Walking is the most fundamental requirement for independent living in daily life. An intelligent walking-support robot has been developed for use by people with walking disabilities. To appropriately assist the user, the robot must precisely track the user’s intentions. However, the robot’s tracking accuracy is severely compromised by time-varying friction, center-of-gravity (CoG) shifts, and load changes induced by the user. In a previous study, we proposed a digital acceleration controller with online inertial parameter identification. However, the tracking accuracy was still affected by CoG shifts introduced by the users. To address these issues, the current study investigated a novel dynamic model, wherein all the load and CoG information processed in the inertial matrix was derived and a new digital acceleration controller with parameter estimation was used to compensate for the time-varying friction, CoG shifts, and load changes. Experiments were conducted under different floor and load conditions to demonstrate the improved tracking accuracy of the proposed control method.     

Motion support during the swing phase using cooperative walking support system

Walking support systems have been developed for supporting the motion of the elderly and physically disabled. In this research, we propose a walking support system based on the cooperation between wearable-type and cane-type walking support systems for supporting hemiplegic patients with disabilities. The system is controlled based on the intended motion of the user, their state and environmental information. In this system, we aim to realize several functions for supporting the daily life of the user by cooperatively controlling each walking support systems including walking support, sit-to-stand assistance, navigation, fall prevention and so on. As the first step to build this system, we focus on the walking support in this paper. For realizing the walking support, we propose a wearable-type walking support system that assists leg motion during the swing phase based on the motion of a cane-type walking support system moved by the user.     

基于北斗/GSM技术的掌上智能防丢防盗系统

基于北斗二代定位技术和GSM通信技术,对物品进行追踪、监控以及防丢防盗等远程智能化管理。系统包括Android智能手机管理端和北斗设备监控端。北斗设备端采用μC/OS-II轻巧型操作系统实现快速任务切换。手机端软件实现手机端用户位置服务功能,如用户定位、用户移动轨迹记录和查询等;实现监控端定位、警报、监控、搜索等功能,用于贵重物体、小孩、老人或智障人等的防丢、防盗远程智能监控。     

A New Directional-Intent Recognition Method for Walking Training Using an Omnidirectional Robot

In order to avoid being bedridden, a preemptive walking rehabilitation is essential for people who lose their walking ability because of illness or accidents. In a previous study, we developed an omnidirectional walking training robot (WTR), the effectiveness of which in rehabilitation was validated by clinical testing. In the primary stage of the walking training, the WTR guides the user to follow the predesigned therapy program to conduct the walking training. This study focuses on the later stages of training in which the user plays an active role of determining the training by himself/herself, and the WTR must follow the user’s intent. However, identifying a user’s intent is challenging. In the present study, we address this problem by introducing a directional-intent identification method based on a distance-type fuzzy reasoning algorithm. The effectiveness of the directional identification method is experimentally confirmed.     

基于LabVIEW的机器人的运动控制系统研究

为了减少机器人运动轨迹误差,实现对机器人的精准控制,提高机器人的运动效率,设计了基于LabVIEW的机器人的运动控制系统;采用了NI公司的控制板卡,选用了Odriver驱动器作为主控制器,选用大力矩伺服电机作为驱动电机,实现运动控制系统的硬件架构的设计;通过脉冲信号驱动电机运动,获取机器人的运动轨迹数据,通过进行对控制...     

Network Distributed Multi-Functional Robotic System Supporting the Elderly and Disabled People

We have been developing a network distributed Human-Assistance Robotic System in order to improve care cost and the QoL (Quality of Life) of the elderly people in the population-aging society. We developed multi-functional robotic system and implemented several CORBA application servers to provide some basic services to aid the aged or disabled. A novel method of localization of mobile robot with a camera and RFID (Radio Frequency Identification) technology is proposed as it is inexpensive, flexible and easy to use in practical environment. A video/audio conference system is also developed to improve the interaction among the users, switch robot manipulating privilege with the help of a centralized user management server, and enable a web-user to get a better understanding of what is going on in the local environment. Considering multi-type user of the developed, we have implemented multiple HRIs (Human Robot Interfaces) that enable different user to control robot systems easily.     

Walking intent detection algorithm for paraplegic patients using a robotic exoskeleton walking assistant with crutches

This paper deals with a walking intent detection algorithm for paraplegic patients using a robotic exoskeleton walking assistant with crutches. User intent detection is one of the most important factors for a robotic exoskeleton to recognize a user??s intent regarding robot operation and in order to conduct proper operation. For a robotic exoskeleton walking assistant, walking intent detection means that the robot recognizes the best time to start walking behaviors and which behavior should be executed from the user??s intent. To enable this detection, an algorithm derived from a finite Moore Automaton for Robot Behavior (MARB) has been developed. Also, a walking stability criterion model is presented for use in the proposed algorithm as a trigger signal for walking. The proposed algorithm and the walking stability criterion modeling were verified using the robotic exoskeleton walking assistant, ROBIN.     

Motion Control of Passive Intelligent Walker Using Servo Brakes

We propose a new intelligent walker based on passive robotics that assists the elderly, handicapped people, and the blind who have difficulty in walking. We developed a prototype of the robot technology walker (RT walker), a passive intelligent walker that uses servo brakes. The RT walker consists of a support frame, two casters, two wheels equipped with servo brakes, and it has passive dynamics that change with respect to applied force/moment. This system is intrinsically safe for humans, as it cannot move unintentionally, i.e., it has no driving actuators. In addition, the RT walker provides a number of navigational features, including good maneuverability, by appropriately controlling the torque of servo brakes based on RT. We propose a human adaptive motion control algorithm that changes the apparent dynamics to adapt to user difficulties, and an environmentally adaptive motion control algorithm, which incorporates environmental information to provide obstacle/step avoidance and gravity compensation functions. The proposed control algorithms are experimentally applied to the RT walker to test their validity.     

Human-assistance robotic system based on distributed computing technology

Population aging is becoming an increasingly pressing problem for society. Thus, the timely development of supporting systems to improve care cost and the quality of life of the elderly is becoming particularly important. Because of the dispersal of the elderly and disabled, a standard software architecture that can implement network-distributed software sharing and improve the cost of writing and maintaining software is in high demand. This paper proposes using distributing computing technology CORBA to integrate network-distributed software and robotic systems for supporting the aged or disabled. Using CORBA as a communication architecture, we implemented a networkdistributed human-assistance robotic system. We developed a hardware base including a robot arm and an omnidirectional mobile robot, developed key technologies such as localization of a mobile robot, real-time recognition, real-time multimedia, and implemented several CORBA servers including a Web user management server, a task-level robot arm control server, a live image and video feedback server, a mobile robot control server, and an indoor Global Positioning System server. With the user controlling a robot arm with 5 d.o.f. to cooperate with an omnidirectional mobile robot, the developed system can provide basic services to support the aged and disabled.     

基于QFD 的老年家用陪护机器人设计

为解决老年家用陪护机器人设计中用户需求多样性的问题,结合质量功能展开 (QFD)方法和Kano 模型,对老年家用陪护机器人用户需求的获取及需求转化展开研究。首先, 以老年用户为研究对象,运用Kano 模糊问卷调查法,从造型、功能、交互3 个方面获取老年 用户需求并对需求进行分类,建立老年家用陪护机器人的QFD 模型。其次,将用户需求转化 为设计要素,确定用户需求相对重要度,建立老年家用陪护机器人的QFD 模型。最后,从造 型、功能、交互3 个方面提出设计解决方案,为老年用户提供了满意的家用陪护产品。以老 年家用陪护机器人为例,将用户重点需求转化为设计要素,提出设计方案,为同类产品设计 提供参考。     

Motion control of wearable-type walking support system based on the spring-mass model

Many systems and control methods have been proposed as mobility supports for the physically disabled and elderly individuals. In this research, we focus on a wearable-type system that supports the elderly with their walking. Different from typical control methods of wearable-type walking support systems, we propose a simple control method based on the spring–mass model. As a walking aid that does not require additional motions, such as sit-to-stand, this simple system is beneficial for two reasons. First, it reduces the calculation cost of deriving the support joint torque of the user; second, the wearable device hardware can be simply constructed from low-power actuators and springs rather than high-power actuators. In stance phase support mode, our motion control method compensates for a part of the force applied to the upper body as a leg muscle support. During the swing phase, walking is supported by a trajectory-following method using the impedance control as well as the spring–mass model. The proposed methods are applied to a prototype of a wearable-type walking support system, and evaluated in a series of experiments on human subjects.     

Adaptive walking control of quadruped robots based on central pattern generator （CPG） and reflex

This paper presents a central pattern generator (CPG) and vestibular reflex combined control strategy for a quadruped robot. An oscillator network and a knee-to-hip mapping function are presented to realize the rhythmic motion for the quadruped robot. A two-phase parameter tuning method is designed to adjust the parameters of oscillator network. First, based on the numerical simulation, the influences of the parameters on the output signals are analyzed, then the genetic algorithm (GA) is used to evolve the phase relationships of the oscillators to realize the basic animal-like walking pattern. Moreover, the animal’s vestibular reflex mechanism is mimicked to realize the adaptive walking of the quadruped robot on a slope terrain. Coupled with the sensory feedback information, the robot can walk up and down the slope smoothly. The presented bio-inspired control method is validated through simulations and experiments with AIBO. Under the control of the presented CPG and vestibular reflex combined control method, AIBO can cope with slipping, falling down and walk on a slope successfully, which demonstrates the effectiveness of the proposed walking control method.     

ANFIS-based sensor fusion system of sit-to-stand for elderly people assistive device protocols

This paper describes the analysis and design of an assistive device for elderly people under development at the EgyptJapan University of Science and Technology(E-JUST) named E-JUST assistive device(EJAD).Several experiments were carried out using a motion capture system(VICON) and inertial sensors to identify the human posture during the sit-to-stand motion.The EJAD uses only two inertial measurement units(IMUs) fused through an adaptive neuro-fuzzy inference systems(ANFIS) algorithm to imitate the real motion of the caregiver.The EJAD consists of two main parts,a robot arm and an active walker.The robot arm is a 2-degree-of-freedom(2-DOF) planar manipulator.In addition,a back support with a passive joint is used to support the patient s back.The IMUs on the leg and trunk of the patient are used to compensate for and adapt to the EJAD system motion depending on the obtained patient posture.The ANFIS algorithm is used to train the fuzzy system that converts the IMUs signals to the right posture of the patient.A control scheme is proposed to control the system motion based on practical measurements taken from the experiments.A computer simulation showed a relatively good performance of the EJAD in assisting the patient.     

基于deep Q-network双足机器人非平整地面行走稳定性控制方法

针对双足机器人在非平整地面行走时容易失去运动稳定性的问题,提出一种基于一种基于价值的深度强化学习算法DQN（Deep Q-Network）的步态控制方法。首先通过机器人步态规划得到针对平整地面环境的离线步态,然后将双足机器人视为一个智能体,建立机器人环境空间、状态空间、动作空间及奖惩机制,该过程与传统控制方法相比无需复杂的动力学建模过程,最后经过多回合训练使双足机器人学会在不平整地面进行姿态调整,保证行走稳定性。在V-Rep仿真环境中进行了算法验证,双足机器人在非平整地面行走过程中,通过DQN步态调整学习算法,姿态角度波动范围在3°以内,结果表明双足机器人行走稳定性得到明显改善,实现了机器人的姿态调整行为学习,证明了该方法的有效性。     

3D stable biped walking control and implementation on real robot

A combination of walking control methods was proposed and implemented on a biped robot. The LIPM-based model predictive control (MPC) was adopted to generate a basic stable walking pattern. The stability of pitch and yaw rotation was improved through pitch and yaw momentum control as a supplementation of MPC. It is found that biped robot walking tends to deviate from the planned walking direction if not considering the rotation friction torque in yaw axis under the support foot. There are basically two methods to control yaw momentum, waist and swing arms rotation control. However, the upper body is often needed to accomplish other tasks. Therefore, a yaw momentum control method based on swing leg dynamics was proposed. This idea does not depend on upper body’s motion and is highlighted in this paper. Through experiments, the feasibility of the combination of the control methods proved to be practical in keeping biped robot walking stable both in linear and rotation motion. The pros and cons of the yaw momentum control method were also tested and discussed through comparison experiments, such as walking on flat and uneven terrain, walking with different payloads.