外骨骼机器人处于摆动相后期系统模型仿真

结合人体解剖学对外骨骼机械人下肢运动进行分析,主要阐述外骨骼处在摆动相后期的运动,根据功率键合图和传递函数混合进行建模,利用SIMULINK对液压缸的压力、速度、加速度和阀芯位移进行仿真,通过仿真结果来验证系统运动的合理性。     

基于心肺复苏用途的上肢外骨骼助力机器人仿真研究

针对心肺复苏助力用途,设计了一种新型的上肢外骨骼助力机器人.以D-H矩阵为基础建立了上肢外骨骼助力机器人的运动学方程,得到机器人末端点的位姿矩阵并验证,利用代数解法求得逆运动学.通过Matlab编程求解出上肢外骨骼助力机器人的可达工作空间.运用ADAMS对机器人进行了运动学和动力学仿真,证明了结构的合理性以及运动学的正确性,同时动力学仿真得到的各关节最大力矩为电机选型和后续的运动控制提供依据.     

脑卒中患者下肢外骨骼康复机器人步态规划与运动学仿真

为满足越来越多的脑卒中患者辅助行走和康复训练的需要,设计了一款下肢外骨骼机器人模型,采用D-H参数法建立踝关节、膝关节、髋关节坐标系,推演出步态周期内的坐标方程。为了安全起见,要求脑卒中患者步行速度慢且步长短,利用CoG(Center of Gravity,重心地面投影点)作为步态规划中的稳定性判断依据,并用Robotics Toolbox for Matlab仿真,结果表明:下肢外骨骼康复机器人在康复训练过程中各关节具有连续且稳定的步态轨迹,为后续脑卒中患者使用的下肢外骨骼康复机器人样机研制提供了必要的理论依据。     

助力下肢外骨骼双膝蹲-起立过程动力学研究

为研究助力下肢外骨骼双膝蹲-起立过程中各关节的驱动力矩,将助力下肢外骨骼视为三自由度的刚性结构系统,建立动力学模型。以达朗贝尔定理推导出双膝蹲-起立过程动力学表达式。为实现助力下肢外骨骼与人体高度偕行,对人体双膝蹲-起立运动过程进行实验分析,以MATLAB为平台分别对负重40kg和无负重下肢外骨骼各关节驱动力矩进行数值计算。根据分析结果得,膝关节在负重40kg时驱动力矩最大,峰值为209.20N·m,平均为75.85N·m;髋、踝关节驱动力矩相对较小,工作能耗低,在无负重状态下仍需9.87N·m和38.80N·m的驱动力矩,能量损失较多;踝关节为保持稳定性导致有较大波动。     

Unpowered Knee Exoskeleton Reduces Quadriceps Activity during Cycling

Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for knee-extension support. We developed an exoskeleton prototype using a crossing four-bar mechanism as a knee joint with an embedded torsion spring. This study evaluates the passive knee exoskeleton using constant-power cycling tests performed by eight healthy male participants. We recorded the surface electromyography over the rectus femoris muscles of both legs, while the participants cycled at 200 and 225 W on a trainer with the developed wheel-accelerating system. We then analyzed these data in time–frequency via a continuous wavelet transform. At the same cycling speed and leg cadence, the median power spectral frequency of the electromyography increases with cycling load. At the same cycling load, the median power spectral frequency decreases when cycling with the exoskeleton. Quadriceps activity can be relieved despite the exoskeleton consuming no electrical energy and not delivering net-positive mechanical work. This fundamental can be applied to the further development of wearable devices for cycling assistance.     

Personalized voice activated grasping system for a robotic exoskeleton glove

This paper proposes a novel human machine interface (HMI) and electronics system design to control a rehabilitation robotic exoskeleton glove. Such system can be activated with the user’s voice, take voice commands as input, recognize the command and perform biometric authentication in real-time with limited computing power, and execute the command on the exoskeleton. The electronics design is a stand-alone plug-and-play modulated design independent of the exoskeleton design. This personalized voice activated grasping system achieves better wearability, lower latency, and improved security than any existing exoskeleton glove control system.     

面向康复工程的助行可穿戴外骨骼机器人的人类工效学设计

中国社会正在逐渐进入老龄化,肢体残疾人群数也在不断增加,这逐渐加剧了我国康复专业人才的供需矛盾。为了缓解该矛盾,针对下肢运动功能完全或部分丧失的偏瘫及截瘫患者,设计了PRMI助行外骨骼机器人。该外骨骼系统对其穿戴者提供运动补偿以帮助其自然和有效地独立行走。介绍了PRMI助行外骨骼机器人设计目的。通过对外骨骼的人类工效学设计的分析,对PRMI外骨骼的可调范围、关节的运动范围、最大力矩、运动学上的一致性以及人机交互进行了介绍。     

Human-machine interaction force control: using a model-referenced adaptive impedance device to control an index finger exoskeleton

Exoskeleton robots and their control methods have been extensively developed to aid post-stroke rehabilitation. Most of the existing methods using linear controllers are designed for position control and are not suitable for human-machine interaction （HMI） force control, as the interaction system between the human body and exoskeleton is uncertain and nonlinear. We present an approach for HMI force control via model reference adaptive impedance control （MRAIC） to solve this problem in case of index finger exoskeleton control. First, a dynamic HMI model, which is based on a position control inner loop, is for- mulated. Second, the theoretical MRAC framework is implemented in the control system. Then, the adaptive controllers are designed according to the Lyapunov stability theory. To verify the performance of the proposed method, we compare it with a proportional-integral-derivative （PID） method in the time domain with real experiments and in the frequency domain with simu- lations. The results illustrate the effectiveness and robustness of the proposed method in solving the nonlinear HMI force control problem in hand exoskeleton.     

Tracking control of time-varying knee exoskeleton disturbed by interaction torque

Knee exoskeletons have been increasingly applied as assistive devices to help lower-extremity impaired people to make their knee joints move through providing external movement compensation. Tracking control of knee exoskeletons guided by human intentions often encounters time-varying (time-dependent) issues and the disturbance interaction torque, which may dramatically put an influence up on their dynamic behaviors. Inertial and viscous parameters of knee exoskeletons can be estimated to be time-varying due to unexpected mechanical vibrations and contact interactions. Moreover, the interaction torque produced from knee joint of wearers has an evident disturbance effect on regular motions of knee exoskeleton. All of these points can increase difficultly of accurate control of knee exoskeletons to follow desired joint angle trajectories. This paper proposes a novel control strategy for controlling knee exoskeleton with time-varying inertial and viscous coefficients disturbed by interaction torque. Such designed controller is able to make the tracking error of joint angle of knee exoskeletons exponentially converge to zero. Meanwhile, the proposed approach is robust to guarantee the tracking error bounded when the interaction torque exists. Illustrative simulation and experiment results are presented to show efficiency of the proposed controller. Additionally, comparisons with gradient dynamic (GD) approach and other methods are also presented to demonstrate efficiency and superiority of the proposed control strategy for tracking joint angle of knee exoskeleton.