基于步态的下肢康复用外骨骼机器人运动分析

穿戴式下肢助行外骨骼机器人是一种能够帮助行走不便的老人和具有行走功能障碍的患者进行辅助行走的仿人服务机器人,其康复训练设备已提升为国家战略性研究项目,越来越得到重视。通过对人体下肢运动机理以及步态的研究,并基于动力学仿真软件Adams对外骨骼机器人的受力和步态进行仿真分析,验证步态的合理性,同时对以后行走的合理性提供依据以及为进一步设计出一种新型穿戴式下肢助行外骨骼机器人样机提供参考。     

面向静态稳定的可变形助行外骨骼机器人运动规划

助行外骨骼机器人能够辅助下肢运动障碍人群站立行走,但相较于电动轮椅在移动距离与移动速度上存在不足。因此设计了一款可变形助行外骨骼机器人,具有助行外骨骼与电动轮椅两种相互独立可转换的形态。针对可变形助行外骨骼机器人变形与行走两种运动过程,研究面向系统静态稳定的运动规划。描述了可变形助行外骨骼机器人的变形原理;提出了基于系统重心投影点位置的运动规划方法,分析了外骨骼机器人在变形与行走过程的静态稳定性;完成了健康受试者穿戴外骨骼的变形与行走运动实验,实验中系统的稳定裕度分别大于54 mm和20 mm。实验结果表明,利用面向静态稳定的运动规划方法,可变形助行外骨骼机器人能够实现稳定可靠的变形切换与连续行走。     

外骨骼助行机器人变刚度驱动的研究进展

外骨骼助行机器人属于科技前沿的热点,具有巨大的应用前景。对外骨骼助行机器人变刚度驱动的国内外研究进展进行了综述,主要介绍了弹性元件的变刚度驱动、杠杆结构的变刚度驱动以及挠性的变刚度驱动,阐明了目前外骨骼助行机器人变刚度驱动的发展瓶颈,展望了外骨骼助行机器人变刚度驱动的未来发展方向。     

一种下肢外骨骼助行康复机器人及康复评价方法

针对下肢瘫痪患者的康复训练需求,设计了一种下肢外骨骼助行康复机器人。描述了外骨骼机器人的机械结构。设计了基于关节角位移的闭环控制系统,将VICON运动捕捉系统采集的正常人体下肢运动关节角作为参考输入信息,控制受试者穿戴外骨骼进行行走、上下台阶动作。完成系统调试后,采用VICON运动捕捉系统捕捉受试者在该控制系统下的步态,并与正常人体步态作对比,验证了控制算法的正确性。定义了下肢康复评价标准RMP,使用设计的外骨骼康复机器人进行患者跟踪康复训练实验,验证了助行康复机器人的有效性。     

无动力下肢外骨骼机器人研究综述及发展趋势

无动力下肢外骨骼机器人,可运用于医疗康复、运动助力以及负载作业等场景。系统阐述了无动力下肢外骨骼机器人的发展背景及助力形式;对国内外无动力下肢外骨骼机器人的研究历程进行综述,按多关节和单关节进行分类,重点总结了两类机器人的结构、特点、优劣势以及效能评估等;围绕无动力下肢外骨骼机器人的关键技术与未来发展趋势进行了分析与展望。     

下肢外骨骼助力机器人关节驱动设计及试验分析

针对人体下肢关节特点与助行要求,设计了外骨骼机器人关节结构;通过ADAMS软件仿真,分析了外骨骼机器人水平助行过程中关节功率配置需求,根据关节需求设计了外骨骼电液伺服驱动系统;为满足外骨骼机器人对人体下肢关节助力及柔顺性要求,提出了基于关节误差估计的PID控制方法。详细介绍了外骨骼机器人下肢关节结构的运动形式与技术参数,优化配置了关节结构的运动范围与驱动行程,对该机器人进行了运动学分析并通过外骨骼的典型动作进行验证;划分了外骨骼助行过程中步态与关节驱动映射,给出误差估计与补偿PID控制的具体参数;分别从关节跟踪与助力功率的角度,量化分析、对比了基于关节误差估计与常规PID两种控制方法的助力指标参数。试验结果表明,所设计外骨骼关节与驱动系统可实现穿戴者助力行走;对比常规PID控制,抑制了关节驱动控制输出区间的不连续,改善了关节跟踪误差,提升了助力效果与柔顺性。     

老年人外骨骼机器人斜坡行走的运动学分析

利用Motion Analysis三维动作捕捉分析系统,记录了老年人穿戴外骨骼助行机器人在20°斜坡行走的步态数据,建立了运动学耦合模型,分析了老年人穿戴外骨骼助行机器人斜坡行走的运动特性。研究结果表明,老年人穿戴外骨骼助行机器人上斜坡时,髋关节的运动范围为5.5°~59.5°,膝关节的运动范围为7.2°~68.2°,踝关节的运动范围为10.4°~32.4°,外骨骼助行机器人的踝关节始终处于背屈状态;老年人穿戴外骨骼助行机器人下斜坡时,髋关节的运动范围为10.1°~30.1°,膝关节的运动范围为9.3°~75.3°,踝关节的运动范围为-8.8°~19.8°,外骨骼助行机器人的踝关节处于背屈和跖屈交替变换的状态,为提高老年人与外骨骼助行机器人在斜坡行走的运动性能提供运动学依据。     

基于应变片式压力传感器的重心测量系统

准确的重心位置对于下肢外骨骼助行机器人的控制具有重要意义。为实现准确快速的重心实时测量,提出了一种基于应变片式压力传感器的重心测量方法,并设计了相应的机械结构和处理电路。该系统能够准确测量出外骨骼机器人与穿戴者构成的人机系统受到的足底反力,并实时计算相应时刻的重心位置。重心测量系统的机械结构可保证压力传感器能够采集到几乎全部的足底反力;力采集电路保证了信号的精确放大和测量。最后进行了系统标定实验,实验表明,系统在采样频率100 Hz时,X向和Y向的测量相对误差均小于2%,能够满足下肢外骨骼助行机器人的控制需求。     

步行康复训练机器人协调控制的研究

为了实现步行康复训练机器人的协调控制,对外骨骼助行腿与跑步机的协调控制以及减重支撑系统与外骨骼助行腿的协调控制,提出了协调控制方法。最后用假人代替真实患者通过实验验证了外骨骼助行腿、跑步机和减重支撑系统之间的协调控制效果。实验结果表明,步行康复训练机器人能够很好的对假人进行减重步行康复训练,外骨骼助行腿、跑步机和减重支撑系统很好地实现了协调控制,同时为进一步对真实患者进行实验研究奠定了很好的基础。     

外骨骼助行机器人的人机耦合运动特性

利用Motion Analysis三维动作捕捉分析系统,实时记录人体在平地行走的运动过程,获得了步态参数,通过分组对比,研究了老年人的行走特点。根据老年人的运动特性,设计了一种老年人外骨骼助行机器人,建立了穿戴者与外骨骼助行机器人的人机耦合模型,研究了人机耦合运动特性,为外骨骼助行机器人的耦合仿生设计提供了运动学基础。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.     

Fractional order nonsingular terminal sliding mode control for flexible spacecraft attitude tracking

This paper investigates a fractional terminal sliding mode control for flexible spacecraft attitude tracking in the presence of inertia uncertainties and extern...     

奥氏体不锈钢表面双辉等离子渗锆的动力学

利用双辉等离子渗金属技术在0Cr18Ni9Ti奥氏体不锈钢表面制备了一层均匀、致密、呈良好冶金结合的渗锆合金层,并对1 060℃下的渗锆动力学进行了研究。结果表明:随着距锆合金层表面距离的增加,锆元素的含量呈梯度递减,扩散系数逐渐减小,而扩散激活能逐步增大;在1 060℃采用双辉等离子技术渗锆时,渗锆合金层表层的空位密度为2.945×(1012~1013)cm-2,与相同温度下采用常规渗金属工艺相比,提高了1~2个数量级。     

气化炉三维扫描测量与数据处理

以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.