School-based use of a robotic arm system by children with disabilities.

A robotic arm system was developed for use by children who had very severe motor disabilities and varying levels of cognitive and language skills. The children used the robot in a three-task sequence routine to dig objects from a tub of dry macaroni. The robotic system was used in the child's school for 12-15 sessions over a period of four weeks. Goal attainment scaling indicated improvement in all children in operational competence of the robot, and varying levels of gain in functional skill development with the robot and in carryover to the classroom from the robot experiments. Teacher interviews revealed gains in classroom participation, expressive language (vocalizations, symbolic communication), and a high degree of interest by the children in the robot tasks. The teachers also recommended that the robot should have more color, contrast and character, as well as generating sounds and/or music for student cues. They also felt that the robotic system accuracy should be increased so that teacher assistance is not necessary to complete the task.     

Customized interactive robotic treatment for stroke: EMG-triggered therapy.

A system for electromyographic (EMG) triggering of robot-assisted therapy (dubbed the EMG game) for stroke patients is presented. The onset of a patient's attempt to move is detected by monitoring EMG in selected muscles, whereupon the robot assists her or him to perform point-to-point movements in a horizontal plane. Besides delivering customized robot-assisted therapy, the system can record signals that may be useful to better understand the process of recovery from stroke. Preliminary experiments aimed at testing the proposed system and gaining insight into the potential of EMG-triggered, robot-assisted therapy are reported.     

Perceptual limits for a robotic rehabilitation environment using visual feedback distortion.

Imperceptible visual distortion, in the form of a disguised progression of performance goals, may be a helpful addition to rehabilitation after stroke and other brain injuries. This paper describes work that has been done to lay the groundwork for testing this hypothesis. We have constructed and validated an experimental environment that provides controllable visual distortion and allows precise force and position measurements. To estimate the amount of visual distortion that should be imperceptible, we measured the limits for force and distance/position perception in our rehabilitation environment for young and elderly unimpaired subjects and for a single traumatic brain injury (TBI) patient. We found the Just Noticeable Difference (JND) for produced force to be 19.7% (0.296 N) and the JND for movement distance/finger position to be 13.0% (3.99 mm) for young subjects (ages 18-35). For elderly subjects (ages 61-80), the JND for force was measured to be 31.0% (0.619 N) and the JND for distance/po'sition was 16.1% (5.01 mm). JNDs of 46.0% (0.920 N) and 45.0% (14.8 mm) were found for the motor-impaired individual. In addition, a subject's rating of effort was found to be profoundly influenced by visual feedback concerning the force magnitude. Even when this feedback was distorted, it accounted for 99% of the variance of the effort rating. These results indicate that substantial visual distortions should be imperceptible to the subject, and that visual feedback can be used to influence the subject's perceived experience in our robotic environment. This means that we should be able to use imperceptible visual distortion to alter a patient's perception of therapeutic exercise in a robotic environment.     

Classification of finger activation for use in a robotic prosthesis arm

Hand amputees would highly benefit from a robotic prosthesis, which would allow the movement of a number of fingers. In this paper we propose using the electromyographic signals recorded by two pairs of electrodes placed over the arm for operating such prosthesis. Multiple features from these signals are extracted whence the most relevant features are selected by a genetic algorithm as inputs for a simple classifier. This method results in a probability of error of less than 2%.     

手指远程康复训练机器人系统设计

将远程康复机器人技术运用到脑卒中患者的康复治疗中,已经得到国内外研究人员的重视,并且已经成为康复领域研究的热点。针对手指受伤或脑卒中患者手指康复医疗的迫切需要,设计了一套基于典型的客户端／服务器（C／S）模式的手指远程康复训练机器人系统,使得医生可以通过音视频远程监控康复训练机构,并根据训练参数做出评估,从而制定出更加科学合理的康复训练计划,有助于在家中或社区医院的脑卒中病人或手指伤残人员的康复训练。临床实践证明,该康复训练系统对偏瘫患者手指功能的康复有促进作用,能够辅助医生对病人进行有效的康复医疗训练。     

Design and validation of a rehabilitation robotic exoskeleton for tremor assessment and suppression.

Exoskeletons are mechatronic systems worn by a person in such a way that the physical interface permits a direct transfer of mechanical power and exchange of information. Upper limb robotic exoskeletons may be helpful for people with disabilities and/or limb weakness or injury. Tremor is the most common movement disorder in neurological practice. In addition to medication, rehabilitation programs, and deep brain stimulation, biomechanical loading has appeared as a potential tremor suppression alternative. This paper introduces the robotic exoskeleton called WOTAS (wearable orthosis for tremor assessment and suppression) that provides a means of testing and validating nongrounded control strategies for orthotic tremor suppression. This paper describes in detail the general concept for WOTAS, outlining the special features of the design and selection of system components. Two control strategies developed for tremor suppression with exoskeletons are described. These two strategies are based on biomechanical loading and notch filtering the tremor through the application of internal forces. Results from experiments using these two strategies on patients with tremor are summarized. Finally, results from clinical trials are presented, which indicate the feasibility of ambulatory mechanical suppression of tremor.     

Robotic techniques for upper limb evaluation and rehabilitation of stroke patients.

This paper presents two robot devices for use in the rehabilitation of upper limb movements and reports the quantitative parameters obtained to characterize the rate of improvement, thus allowing a precise monitoring of patient's recovery. A one degree of freedom (DoF) wrist manipulator and a two-DoF elbow-shoulder manipulator were designed using an admittance control strategy; if the patient could not move the handle, the devices completed the motor task. Two groups of chronic post-stroke patients (G1 n = 7, and G2 n = 9) were enrolled in a three week rehabilitation program including standard physical therapy (45 min daily) plus treatment by means of robot devices, respectively, for wrist and elbow-shoulder movements (40 min, twice daily). Both groups were evaluated by means of standard clinical assessment scales and a new robot measured evaluation metrics that included an active movement index quantifying the patient's ability to execute the assigned motor task without robot assistance, the mean velocity, and a movement accuracy index measuring the distance of the executed path from the theoretic one. After treatment, both groups improved their motor deficit and disability. In G1, there was a significant change in the clinical scale values (p < 0.05) and range of motion wrist extension (p < 0.02). G2 showed a significant change in clinical scales (p < 0.01), in strength (p < 0.05) and in the robot measured parameters (p < 0.01). The relationship between robot measured parameters and the clinical assessment scales showed a moderate and significant correlation (r > 0.53 p < 0.03). Our findings suggest that robot-aided neurorehabilitation may improve the motor outcome and disability of chronic post-stroke patients. The new robot measured parameters may provide useful information about the course of treatment and its effectiveness at discharge.     

RM-501机器人机械臂双重控制系统设计

对于数学模型参数未知和参数时变的系统,采用自适应控制存在的主要问题是在快速调节过程中过渡过程出现大的超调量.分析基于确定性等价原则的自适应控制器和谨慎控制器的局限性,提出一种模型参考自适应双重控制算法,该算法能够有效地防止因为参数估计的不精确而导致的控制性能下降甚至失稳的状况,同时也避免了谨慎控制系统的"关断"现象.为验证双重自适应控制算法的控制特性,将其应用于机械臂的运动控制,并对3种控制算法进行仿真研究.研究结果表明双重控制器的控制性能(超调量和调节时间)优于基于确定性等价原则的自适应控制器和谨慎控制器的性能.     

Estimation of internal structure and viscoelasticity from mechanical impedance

Body structure influences tactile sensation and stiffness evaluation. Conversely, this suggests that internal body structure and stiffness can be estimated from the skin surface. This paper deals with an estimation not only of body structure but also of viscoelasticity under the skin surface by using acoustic random vibration (30 to 1000 Hz). This method allows morphological and functional measurement of the interior of the body. The shape and viscoelasticity of internal objects (tumor, simulated by silicone gel) are estimated from the mechanical impedance measured at the surface. The viscoelasticity and effective vibrating radius are calculated from the impedance spectrum and give a relation between the depth and viscoelasticity of the internal object. The experimental silicone gel model includes two internal hemispheric gels, whose stiffness is different from that of the peripheral silicone gel. The 3-D image of the internal hemispheric gel is reconstructed, based on the relation between the depth and the effective vibrating radius. The viscoelasticity of the internal hemispheric gel is also estimated, based on the relation between the depth and the measured viscoelasticity of the silicone gel slope model. © 1998 Scripta Technica, Electr Eng Jpn, 125(3): 30–39, 1998     

基于机械臂的管道检测全向机器人设计

随着综合地下管廊的快速发展,管道的安全对于保证管廊电力、燃气等运输的安全越来越重要,由于管廊环境恶劣,采用人工巡检效率低且安全隐患大。为了实现地下管廊全方位无盲区检测,设计了一种基于机械臂的管道检测全向机器人,将移动机器人、机械臂、检测探头融于一体,具有路径自主规划、循迹、避障等功能,并通过漏磁技术检测管道泄露、通过机械臂实现复杂环境下的检测。实验证明此集成机器人可以进行全方位检测且缺陷识别精度良好。     

磁诱导对脑卒中患者运动康复的影响研究

探索了磁诱导对脑卒中患者运动康复的影响,设计了磁场诱导大脑自发脑电的实验方法,通过极低频(16 Hz)、低强度(20 m T)脉冲磁场作用于8位脑卒中患者的患侧脑区,同时采集静息状态下的脑电信号并对数据进行分析,利用Jebsen-Taylor手功能测试(JTT)和结合简化Fugl-Meyer运动功能评定量表和改良的Barthel指数评定量表评定康复效果。实验结果显示,磁诱导后量表评分显著升高,脑电高频段能量在运动皮层处有所增加。研究表明,磁诱导技术对脑卒中病人的康复有积极影响,可与传统康复疗法相结合在神经康复中起到辅助作用。     

A model for human skin impedance during surface functional neuromuscular stimulation.

A new mathematical model for the bulk electrical impedance of human skin is presented. In particular this model describes the impedance of skin during surface functional neuromuscular stimulation (FNS) with square stimulation pulses. Experimental data are presented that illustrate the nonlinear dynamic properties of human skin during current and voltage controlled stimulation. Model predictions are compared to experimental data, measured under both constant voltage and constant current transcutaneous stimulation. It is found that this model captures a variety of nonlinear time-varying effects observed in the skin impedance when stimulating with either protocol. This model may be used as part of large neuromusculoskeletal models or in the more accurate modeling of transcutaneous FNS, which is currently the most common clinical implementation of FNS.     

基于谐波阻抗测量在线估测蓄电池荷电状态

现行内阻法估测蓄电池荷电状态时,需要对被测蓄电池实施大电流放电操作以测量其欧姆内阻,在线检测时可能对用电负载造成安全隐患。针对这一问题,提出一种基于谐波阻抗测量技术在线估测蓄电池荷电状态的方法：对被测蓄电池实施周期性的小电流放电操作,测量放电过程中的放电电流与蓄电池端电压,经傅里叶分析计算出蓄电池的谐波阻抗,对谐波阻抗数据进行数值拟合得到蓄电池的欧姆内阻,最终实现对蓄电池荷电状态的在线估测,从而避免现行方法所需要的大电流放电操作。     

Wavelet transforms for real-time estimation of transmission line impedance under transient conditions

 Waveforms of voltages and currents in electrical power systems may include higher harmonics, transient components and random noise. For control and protection devices, it is necessary to estimate parameters of the basic waveform. The most well-known methods are based on the Fourier technique. The estimated phasors of the basic component can be applied to the calculation of the impedance of a faulty transmission line. In this paper, the current and voltage phasors were estimated using complex wavelets. The filter properties of the wavelet approach are better than those of the Fourier. Received: 20 July 2001/Accepted: 10 August 2001     

基于SVM的生物电阻抗人体内脏脂肪测量研究

应用支持向量机(SVM)对生物电阻抗测定人体内脏脂肪过程进行测量建模,解决信号复杂,受影响因素多,难以建立精确预测模型问题。为提高预测精度,引入人体腹部形状作为测量人体内脏脂肪的相关特征参数,将SVM参数的选择和输入变量的选取看作组合优化问题,通过AIC信息准则构造组合目标优化函数,采用粒子群算法进行目标函数搜索,提高了搜索效率。通过仿真研究表明,所提基于SVM的生物电阻抗人体内脏脂肪含量测量方法具有良好的性能。     

Further enhancements in the symmetrical components based improved fault impedance estimation method Part I. Mathematical modelling

This paper develops an approach that can be used for further enhancement of the symmetrical components based improved fault impedance estimation method that has previously been proposed by the authors. In addition to discussing the mathematical basis of the new approach, enhanced and computationally efficient performance equations are presented. In view of the recent advancements in optical transducers and high speed optical fibre communications, the new technique uses sequence components of voltage and current samples obtained from both the ends of the protected transmission line. It is also shown in the paper that the new performance equations are independent of fault resistance. The PC based Alternative Transients Program was used to model a six bus system and to generate fault data. The results of performance assessment studies on this new method are presented and discussed in Part-II of this companion paper.     

Further enhancements in the symmetrical components based improved fault impedance estimation method Part II. Performance evaluation

An approach that can be used for further enhancing the symmetrical components based improved fault impedance estimation method has been proposed by the authors in Part-I of this companion paper. The PC based alternative transients program (ATP) was used to model a six bus system and generate fault data. The performance of the proposed method was assessed using the generated fault data. The results of performance assessment studies are presented and discussed in this paper. The proposed method was also applied for calculating an exact fault location. It is also shown in the paper that the proposed method provides highly accurate fault location estimates based on the distance relaying information.     

State-of-health estimation of lithium-ion batteries based on electrochemical impedance spectroscopy: a review

Lithium-ion batteries (LIBs) are crucial for the large-scale utilization of clean energy. However, because of the com-plexity and real-time nature of internal reactions, the mechanism of capacity decline in LIBs is still unclear. This has become a bottleneck restricting their promotion and application. Electrochemical impedance spectroscopy (EIS) contains rich electrochemical connotations and signifcant application prospects, and has attracted widespread atten-tion and research on efcient energy storage systems. Compared to traditional voltage and current data, the state-of-health (SOH) estimation model based on EIS has higher accuracy. This paper categorizes EIS measurement methods based on diferent principles, introduces the relationship between LIBs aging mechanism and SOH, and compares the advantages of diferent SOH estimation methods. After a detailed analysis of the latest technologies, a review is given. The insights of this review can deepen the understanding of the relationship between EIS and the aging efect mechanism of LIBs, and promote the development of new energy storage devices and evaluation methods.