5-DOF上肢康复机械臂交互式康复训练控制策略

设计一种5-DOF穿戴式偏瘫上肢康复机械臂系统,提出被动和主动两阶段的交互式康复训练控制策略。在被动训练中,根据偏瘫患者上肢单侧受损的特点,提取偏瘫患者的健侧上肢4块肌肉的表面肌电信号(Surface electromyogram, sEMG) 作为康复机械臂的控制信号,利用AR参数模型和BP神经网络来理解患者的运动意图,驱动机械臂辅助患侧上肢实现特定的康复训练动作。在主动训练中,通过实时获取各关节力矩信号来判断人体上肢的运动所产生的作用力方向与大小,并利用比例控制器和运动学雅可比逆矩阵控制康复臂末端速度、驱动各关节运动。试验结果证明了提出方法的正确性和有效性。     

Development and validation of an electrogoniometric wrist alignment device

This paper reports the development of an instrumented flexible electrogoniometric hand posture corrective device designed specifically for monitoring and controlling the range of motion (ROM) at the hand and wrist. The device, known as the wrist alignment device (WAD), consists of flexible electrogoniometers attached to a Lycra glove and a control box housing the WAD circuitry. The WAD controls the wrist ROM within set limits by means of presetting the joint angle ranges prior to commencing measurements, thereby preventing or reducing extreme wrist ulnar deviation, wrist hyperflexion, and wrist hyperextension. Additionally, the device consists of a window comparator, which allows the joint movement always to remain within the set limits. Where the subject's wrist ROM is outside the presettings, a piezo-buzzer is triggered which alerts the subject to reduce the ROM, thereby ensuring that the joint angles are always kept within the preset angle range. All instrumentation associated with the development of the device underwent calibration. As a device, it has widespread applications within the office and clinical environment. Preliminary results indicate that reliable measurements based on ROM settings can be obtained when using the WAD.     

A purpose-built dynamometer to objectively measure static and dynamic knee torque

This paper reports the development of a purpose-built knee dynamometer (PBKD) to evaluate passive range of motion (ROM) and isometric muscle strength measurements of the knee. The PBKD uses a TorqSense rotary torque transducer and objectively measures isometric knee muscle strength in a valid and reliable manner and passive resistance to motion through range. The device and all associated instrumentation underwent dynamic and static calibration to ensure consistent and accurate measurements were obtained in terms of knee joint angular position, passive torque measures, and isometric torque measures. Eleven healthy male participants performed a knee flexion and extension task designed to evaluate knee function. The validation of the PBKD entailed measuring the consistency of measurement and accuracy of measurement. Accuracy of the PBKD was determined by comparing peak isometric muscle strength measurements against a KIN-COM machine. No significant differences were observed both passively and isometrically between cycles and between trials. This device can have widespread applications within the rehabilitation and clinical environment and could be used as a functional outcome measuring tool to distinguish pathological from non-pathological knees. The presented preliminary results indicate that reliable and accurate measurements of knee ROM and muscle strength can be obtained.     

Design and implementation of a novel modal space active force control concept for spatial multi-DOF parallel robotic manipulators actuated by electrical actuators

Robotic spine brace based on parallel-actuated robotic system is a new device for treatment and sensing of scoliosis, however, the strong dynamic coupling and anisotropy problem of parallel manipulators result in accuracy loss of rehabilitation force control, including big error in direction and value of force. A novel active force control strategy named modal space force control is proposed to solve these problems.Considering the electrical driven system and contact environment, the mathematical model of spatial parallel manipulator is built. The strong dynamic coupling problem in force field is described via experiments as well as the anisotropy problem of work space of parallel manipulators. The effects of dynamic coupling on control design and performances are discussed, and the influences of anisotropy on accuracy are also addressed. With mass/inertia matrix and stiffness matrix of parallel manipulators, a modal matrix can be calculated by using eigenvalue decomposition. Making use of the orthogonality of modal matrix with mass matrix of parallel manipulators, the strong coupled dynamic equations expressed in work space or joint space of parallel manipulator may be transformed into decoupled equations formulated in modal space. According to this property, each force control channel is independent of others in the modal space, thus we proposed modal space force control concept which means the force controller is designed in modal space. A modal space active force control is designed and implemented with only a simple PID controller employed as exampled control method to show the differences, uniqueness, and benefits of modal space force control. Simulation and experimental results show that the proposed modal space force control concept can effectively overcome the effects of the strong dynamic coupling and anisotropy problem in the physical space, and modal space force control is thus a very useful control framework, which is better than the current joint space control and work space control.     

多模式柔顺膝关节康复器设计及力分析

研究开发了一种多模式柔顺膝关节康复器,提出了无杆气缸+气动柔性驱动器的复合驱动技术,保证了对膝关节康复训练柔顺性和大行程的要求.设计了康复器的结构和控制系统的软、硬件,并对康复器的驱动力进行了分析.所研发的康复器可实现膝关节主动、被动等多种模式的康复训练.     

固高工业机器人力/位混合控制

针对固高工业机器人末端主动柔顺控制实现问题,改进并设计了力/位混合控制系统.采用PC+PCI总线采集控制卡的结构,给出了相应的硬件及软件实现方法.实验表明该系统具有良好的稳定性和动态性能.     

滑模控制在电液伺服力控系统中的应用与研究

针对电液伺服力控系统存在的非线性,导致系统在运动时引起多余力的问题,提出了采用滑模变结构的控制方案。通过对PID和滑模变结构控制在无扰动和有扰动情况下的仿真曲线对比,可以明显看出滑模控制明显优于PID控制。     

绳索驱动式变刚度关节柔顺控制与力补偿方法研究

机器人柔顺运动有助于提高机器人交互运动时的安全性与稳定性,越来越受到人们的重视。针对一种绳索驱动式具有主被动柔顺性的柔性机器人关节,提出一种适用于绳索驱动式变刚度关节的刚度与位置解耦控制方式,实现了关节位置控制的同时,又实现了关节柔顺性的统一。利用雅可比矩阵和模型间静力学关系,得到关节刚度模型,并通过优化方法对变刚度装置的力学模型和刚度模型构成的非线性方程组求解,实现变刚度关节刚度与位置的非线性解耦。在解耦控制基础上提出一种力矩观测方法,实现了关节力矩补偿,增强了关节位置控制能力;建立了绳索驱动式变刚度关节样机和控制系统,并通过仿真和实验分析的方式验证了所提柔顺控制方式的可行性和有效性。     

软质肘关节外骨骼的肌力矩估计与神经网络补偿协调控制

为辅助偏瘫患者进行多模式肘关节康复训练,研制了一种软质肘关节康复外骨骼机器人,并提出了一种基于人体肌力矩估计与自适应神经网络补偿的协调控制策略。利用表面肌电信号来识别人体的运动意图并调整康复训练轨迹,采用Lyapunov方法证明了控制算法的闭环控制稳定性。搭建了实时控制实验平台,并开展了基于运动意图的轨迹跟踪实验与自由主动训练实验。实验结果表明,所提控制策略能保证被动训练过程的轨迹跟踪精度,并且可以根据患者的运动意图调整主动训练过程的运动轨迹,实现不同强度的主动康复训练。     

Robotic automatic assembly system for random operating condition

A vision guided tabletop robotic assembly system is constructed for the random environment automatic assembly purpose. The distributed control structure is designed for this assembly system. A PC is specified as the central control unit for machine vision operation and the harmonization of At89c51 distributed control unit for each axis. The machine vision is introduced to search the locations and measure the size of the assembly parts in the robotic workspace. Then, the central controller commands the robot to pick the part sequentially based on the specified program to complete the automatic assembly process. The model-free fuzzy sliding mode control scheme is embedded in each joint micro controller for simplifying the model based control problem. The central control unit PC communicates with each joint controller by network communication. This assembly system is implemented on a 3 DOF SCARA robot. The experimental results show that the robotic motion control performance is good enough for assembling work; the vision pattern classification and assembly motion paths planning and monitoring are exactly executed by the central control unit. The goal of this robotic random assembly operation is achieved with the appropriate integration of robotic motion control, machine vision, sensor and assembly force detecting techniques.     

馈能磁流变半主动悬架模糊滑模控制

为优化悬架减振性能和馈能性能,提出了一种馈能磁流变减振器结构,并设计了相应的半主动悬架模糊滑模控制策略。建立了磁流变减振器力学模型和馈能模型,以及相应的二自由度半主动悬架系统数学模型。针对半主动悬架系统的不确定性,基于混合天地棚阻尼控制系统,设计了滑模变结构控制器。使用饱和函数缓解系统抖振,并运用模糊控制优化滑模控制器。用谐波叠加法生成路面激励输入,分别对被动悬架、基于混合天地棚阻尼控制的半主动悬架以及基于模糊滑模控制的半主动悬架进行对比仿真。结果表明：基于模糊滑模控制的半主动悬架减振性能更好,能耗更小,且有良好的馈能性能,验证了馈能磁流变减振器结构的可行性和模糊滑模控制策略的有效性。     

基于屏障 Lyapunov 函数的上肢康复机器人 自适应主动交互训练控制

针对上肢运动功能障碍患者进行辅助康复训练,搭建了一套上肢康复外骨骼机器人系统,并提出一种基于屏障Lyapunov函数的增广神经网络自适应导纳控制策略。首先,介绍了上肢康复外骨骼的机械机构及其控制系统。然后,推演了控制器的设计过程并进行了Lyapunov稳定性证明。最后,分别进行了不同控制内环的轨迹跟踪被动训练实验和不同导纳参数下基于人机交互力的主动交互训练实验,同时分析比对了主动训练时的人机交互力与轨迹偏差的变化关系。被动训练实验结果证明了增广神经网络对人机模型动力学的逼近效果,其轨迹跟踪峰值误差为模糊PID控制器的53%。主动交互训练实验证明了通过调整导纳参数可实现在相同训练任务下不同强度的康复训练以匹配不同康复阶段下的患者。     

基于足底力反馈的踝关节主被动康复策略

踝关节机能损伤人群数量增长与康复医师紧缺是现阶段面临的一个重要社会问题,为此,基于一款2-SPU/RR踝关节康复机器人提出一种主被动结合的辅助康复策略。首先建立虚拟样机模型和对应的结构简图,进行运动学分析,求解了机器人的工作空间,结果表明该机器人能够满足踝关节跖屈-背屈和内翻-外翻复合运动需求。然后针对目前康复机器人主要研究内容为被动康复问题,未能根据患者脚踝实际损伤情况进行康复,提出一种踝关节机器人主被动康复结合的方法。先预设康复运动轨迹,基于足底压力数据和力感知算法获得患者的运动意图,通过软硬件控制系统实现机器人主动跟随,同时将运动轨迹进行记录和数据化。最后对描迹轨迹进行优化,根据优化轨迹使用5段S型加减速控制方式进行定制化被动康复。主被动康复系统实现了机器人跟随控制与患者主动行为感知的结合,有助医师对踝关节机能损伤患者的诊断与治疗。     

潜艇浮筏隔振系统的半主动模糊滑模控制

对带有电流变液智能阻尼器的双层浮筏隔振系统设计一种半主动静态输出反馈模糊滑模控制器.根据滑模运动方程稳定的Hurwitz判据选择滑模面矩阵.根据滑模到达条件及可控屈服阻尼力对隔振系统做负功原理设计半主动输出反馈模糊滑模控制器.仿真分析浮筏隔振系统在扫频激励信号下的力传递率及在双频激励信号下的输入力和输出力曲线.仿真结果表明,半主动输出反馈模糊滑模控制下的浮筏隔振系统的减振效果要远好于最优被动阻尼系统.     

基于人机耦合模型的上肢康复外骨骼闭环PD迭代控制方法

针对多关节上肢外骨骼重复性康复训练非线性求解困难问题,提出了一种闭环PD迭代学习控制方法。基于人体工学确定了六自由度上肢外骨骼康复机械臂的参数、自由度配置与关节运动范围。以人机交互力为耦合方式,建立了基于牛顿-欧拉法的人机耦合模型,完成了人机耦合动力学模拟分析。基于迭代学习控制理论提出外骨骼康复机械臂的闭环PD迭代学习控制方法,通过建模仿真分析了肩关节/肘关节迭代学习控制的轨迹误差、人机交互力和驱动力矩。第三次迭代后的轨迹误差小于0.05 rad,PD迭代学习控制器的输出对系统控制进行了有效的补偿,提高了系统状态的稳定性。研制了六自由度上肢外骨骼康复机械臂样机,开展试验测试。试验结果表明,随着控制试验在迭代域上的运行,系统的输出向着期望的系统状态转化,所提出的迭代学习控制算法可以提高上肢外骨骼康复训练重复性运动的控制精度,进而提高人机交互性能。     

模糊控制在工业机器人中的应用研究？

工业机器人各关节之间关系十分复杂,其转动惯量随着运动位置的变化而变化是非线性控制。要使工业机器人的各关节达到高精度、无超调及快速平稳控制是技术难题。通过介绍工业机器人模糊控制系统的结构及其模型建立的过程,分析了机器人模糊控制的关节控制系统及调节特性。实践表明将模糊控制应用于工业机器人控制可以达到良好的控制性能要求。     

潜艇浮筏隔振系统的控制研究

为带有电流变阻尼器的双层浮筏隔振系统设计了一种半主动模糊滑模控制器。根据滑模运动方程稳定的Hurwitz判据选择了滑模面系数,并根据滑模到达条件设计了半主动模糊滑模控制器。仿真分析了浮筏隔振系统在扫频激励信号下的力传递率及双频激励信号下输入力和输出力的曲线。仿真结果表明：半主动模糊滑模控制下浮筏隔振系统的减振效果要远好于最优被动阻尼系统。     

树障清理空中机器人的姿态控制器设计

以一种用于对高压线路附近的树障进行清理的树障清理空中机器人为研究对象,分析其姿态控制问题。首先,建立了具有新型结构的树障清理空中机器人的姿态动力学模型和控制分配矩阵。然后,为了克服惯性矩阵的不确定性,采用滑模方法设计姿态控制器;同时,引入非线性函数来改进传统的边界层法以提高控制器性能;接着提出了一种切换控制分配矩阵的方法来解决空中机器人在切割作业过程中的动力学模型变化的问题。最后,在仿真平台上实现了上述控制器。实验结果表明,本滑模控制器具有良好的姿态控制性能,能有效克服机体惯量的不确定性;通过切换控制分配矩阵实现了空中机器人在切割作业过程中的姿态稳定。     

三连杆轮式蛇形机器人设计及运动分析

为了克服被动轮驱动蛇形机器人运动能力弱的缺点,提出了一种新型三连杆主动轮驱动蛇形机器人。该蛇形机器人由多个被动关节连接的串联连杆组成,每个连杆的中心都有一个主动全向轮。全向轮的驱动力只作用于横向,而机器人则沿纵向运动。此外,针对该蛇形机器人具有非完整约束和欠驱动的特点,采用局部坐标系,设计了一种带有防滑功能的运动控制器,使运动和关节角度互不干涉。蛇形机器人蜿蜒爬行实验结果表明,所提出的设计是可行的,且运动控制器有效避免了全向车轮的打滑问题,提高了整个系统的稳定性。     

A new mechanism design of electro-magnetic actuator for a micro-positioner

This paper proposes a new type of non-conventional electro-magnetic actuator (EMA) for micro-positioning. It is a repulsive magnetic system consisting of a motion pad and two active coils. The motion of the pad is caused by the repelling force between the coils and the permanent magnets on the pad. First, the dynamic model is derived and analyzed. Next, an adaptive sliding mode controller is developed to deal with the unknown parameters with the objective of precision positioning. The experimental results demonstrate satisfactory performances including regulation accuracy and control stiffness for the system.