基于六轴传感器的步态分析系统设计

步态分析可以客观、定量地反映偏瘫患者步态的异常,在临床中应用广泛,但多年来一直缺乏多种步态参数综合反映步态异常的方法。步态分析系统通过设计基于六轴数据传感器的数据采集收发模块,对采集到的六轴运动数据用LabVIEW进行处理,得出步长、髋膝关节角度。通过系统测试,对系统的稳定性和精度进行了验证,测试结果表明:该步态分析系统方便快捷,可以很好地对病人的步态的相关参数进行采集和存储,为医生对病人病情的分析提供参考,具有性能稳定、微型、低功耗、成本低、方便便携等特点。     

基于EtherCAT的并联六自由度平台设计

在设计六自由度运动平台时,运动精度是重要的评价指标,为了能够降低位姿跟踪误差并提高各轴的协同控制,在对平台进行位姿正反解的基础上,设计了一套基于EtherCAT总线的六自由度运动平台,通过EtherCAT网络进行数据帧的快速传输;系统硬件由工控机、EtherCAT网络、伺服电机、Stewart型平台构成,系统软件则采用VC++进行上位机界面的开发,由TwinCAT进行下位机控制程序的开发,通过电子凸轮实现平台各轴的同步控制,其中上下位机通过ADS进行通讯;由实验结果可知,六自由度平台平移跟踪误差小于0.04 mm,转动跟踪误差小于0.01°,静态定位精度优于0.1%,达到预定的控制要求;基于EtherCAT的六自由度平台具有良好的同步性能和位姿精度,也表明EtherCAT在多轴同步伺服控制上具有较好的响应速度和控制精度。     

旋翼无人机六自由度飞行测试系统设计与应用

为安全、精准、高效地解决旋翼无人机实际飞行测试环节的数据依据问题,从被测对象的运动约束及测试需求出发,设计被动悬挂结构的六自由度运动机构,解析需要检测的四个关键参数,给出基于绝对编码的信号检测方案,形成了一种用于旋翼无人机整机飞行测试的全通道运动、多参数检测的实验系统。针对测试系统传感数据进行校对实验,验证了数据测试的有效性。与典型下端球铰链连接支撑方式的三通道检测装置进行了相同条件下的应用对比测试,验证了该测试系统在初始静稳定及抑制震荡方面的优越性。     

基于人体传感和Android技术的运动监测系统设计与实现

为了避免运动过程中和比赛中运动姿态不正确以及运动过量对身体造成的伤害,提出了基于人体传感和Android技术的运动监测系统的设计,在运动过程中对人体运动参数和运动姿态实时监测,通过Android平台实现卡路里消耗计算和运动姿态建模评估,以避免出现运动损伤和体能透支现象。监测系统以MSP430单片机为控制核心,采用MPU6050三轴加速度传感器实时测量人体三轴加速度,利用Android平台计算加速度、速度、里程等运动参数、运动中消耗的卡路里能量,以及人体运动轨迹跟踪、定位;并通过人体运动模型识别算法评估人体运动姿态,实现危险动作预判。实验证明系统能够实现实时运动监测、运动跟踪定位,保护运动者的身体健康。     

基于立体视觉的串联机器人跟踪检测系统

建立一种六自由度串联机器人视觉跟踪检测系统框架,包括图像采集、摄像机标定、机器臂跟踪检测、机器臂位姿建模与计算等。提出利用CamShift算法对机器人进行在线粗跟踪,搜寻和画定出机器臂操作器在当前窗口的区域位置。对跟踪到的机器臂按照SURF算法进行特征提取与立体匹配。该方法被用于对串联机器人位姿检测进行实验。实验结果表明,2种算法的结合适用于六自由度串联机器人在空间复杂运动的跟踪检测。     

基于三轴加速度传感器和电子罗盘的人体摔倒监测系统

设计了一种具有远程监控功能的人体摔倒监测系统,为实现系统的小体积和低功耗,系统硬件主要由MSP430F149单片机、三轴加速度传感器、电子罗盘和无线通信模块组成,由MMA8453Q采集人体运动过程中的三轴加速度数据、CPS320T模块采集人体运动状态参数、无线模块nRF24L01实现系统与工作站间的数据通信.分析了系统的主要硬件模块的接口电路设计方法,并给出了基于硬件的摔倒监测算法.实验结果表明,本系统摔倒监测准确率达98.8％,功耗低,具有很强的实用性.     

基于ARM与LabVIEW的智能健身系统

本文设计了出一个智能健身系统,本系统通过以S3C44BOX为核心的下位机实时跟踪运动中人体的生理参数变化,并把下位机采集到的数据通过USB接口传输到上位机,通过应用程序LabVIEW的虚拟控制面板进行显示并自动对健身仪的运动时间及强度进行调节,从而减少了运动损伤,达到了安全运动的目的。     

人体运动的测量与数据修正

人体是层次化、高度复杂化的形体，对人体运动的研究涉及到机器人、人机工程、仿真等多个学科领域，研究的基础是真实人体的运动数据。本研究采用基于多摄像机跟踪固定在人体上的标记点的光学测量方法，进行人体运动数据的实时跟踪采集。为修正采集系统输出数据件中的错误，采用了可视化技术与方法，生成了人体运动数据的二维、三维检测工具，从而实现了大量数据的快速检测与修正。修正及转换过的运动数据能够很好地驱动三维高逼真度人体仿真模型，并应用于战场环境士兵仿真以及救援操作作业人员的仿真应用，取得良好效果。     

基于ARM与LabVIEW的智能健身系统

本文设计了出一个智能健身系统,本系统通过以S3C44B0X为核心的下位机实时跟踪运动中人体的生理参数变化,并把下位机采集到的数据通过USB接口传输到上位机,通过应用程序LabVIEW的虚拟控制面板进行显示并自动对健身仪的运动时间及强度进行调节,从而减少了运动损伤,达到了安全运动的目的.     

基于改进型RLM算法的六轴机械臂运动学标定实验

六自由度机械臂为高维性、强耦合的非线性时变系统,其模型较复杂,参数辨识易受外界扰动影响,导致末端绝对定位精度低,精度一致性差等问题。以某型六轴机械臂为研究对象,根据微分运动学原理并忽略高阶项,获得末端线性误差模型,提出了收敛速度快且鲁棒性较强的改进型RLM算法进行几何参数的误差辨识,在此基础上搭建综合标定实验平台,利用静态测量精度较高的API T3三维激光跟踪仪采集工作空间中灵敏度较高的样本位姿点,根据国际标准ISO 9283中的位置精度评价标准,比较标定前后的位置误差分布区间,并对分析结果给出评价和总结,完成六自由度工业机械臂本体标定实验。     

A robust trajectory tracking control of a polishing robot system based on CAM data

Polishing a die that has free-form surfaces is a time-consuming and tedious job, and requires a considerable amount of high-precision skill. In order to reduce the polishing time and cope with the shortage of skilled workers, a user-friendly automatic polishing system was developed in this research. The polishing system is composed of two subsystems, a three-axis machining center and a two-axis polishing robot. The developed polishing system with five degrees of freedom is able to keep the polishing tool normal to the die surface during operation. A sliding mode control algorithm with velocity compensation is proposed to reduce tracking errors. Trajectory tracking experiments showed that the effect of reducing the tracking error by the proposed sliding mode control is superior to that by the proportional derivative control. The polishing data is generated from computer-aided design (CAD) data or from teaching data by PolyCAM, a computer-aided manufacturing (CAM) system consisting of 4 modules: a geometric modeller, a CAD data exchange module, a polishing data generation module, and a graphic simulator. To evaluate the performance of the polishing robot system, some polishing experiments on a shadow-mask die were performed.     

老年人运动状态监测和跌倒报警系统

体育锻炼是促进老年人健康长寿的有效手段之一。为了对老年人的运动状态进行实时监测,掌握运动状态参数,并能够对老年人不慎意外踏空或者某种疾病突发导致的跌倒及时报警,设计一种能够实时监测老年人跌倒动作发生并发送定位及报警信息给远程接收端的便携式监测系统。系统采用腰部三轴加速度传感器实时采集人体运动姿态数据;使用嵌入式处理器和无线网络实现数据处理、无线传输和远程报警;通过三级阈值的人体跌倒检测算法,实现人体跌倒姿态变化的加速度特征提取,对人体运动状态进行分级,预测严重的跌倒行为。实验结果表明：该系统具有性能稳定、正确率高和轻巧方便等特点,非常适合老年人穿戴使用,可保障老年人运动安全,应用前景广阔。     

人体姿态检测及数据传输系统设计

本文设计的人体姿态检测及数据传输系统系统,采用了ST公司推出的iNEMO模块,该模块包含三轴加速度计、三轴磁力计、三轴陀螺仪和压力传感器,并将10自由度的传感器模块和32位MCU整合在一起,同时还配备多个通信接口。系统采用了基于SIM300的GPRS模块,将实验员当前的姿态发送到PC客户端,实现了远程监控功能。本系统具有集成化、智能化和平台化等特点,具有良好的应用前景。     

基于MEMS的可穿戴无线体域网设计与实现

针对高精度低成本可穿戴式人体动作捕捉,采用MEMS微惯性传感单元(IMU)设计实现无线体域网系统.系统由六轴微惯性单元MPU-6050、三轴地磁仪AK8975、微处理器及射频模块CC2530构成.首先,详细讨论系统硬件构架和基于Z-Stack的软件构架,然后通过上位机Matlab用户程序进行数据采集与实验验证.实验结果表明,与其他微惯性传感器系统相比,本设计采用高集成度的芯片和无线通信方式,在减小硬件体积的同时能够获得较高精度的数据(角度传感器零漂＜1.5°),对实现可穿戴无线惯性测量有着积极的作用.     

On Melnikov's method in the study of chaotic motions of gyrostat

The homoclinic solutions of the attitude motion of a gyrostat with wheels along its principal axes are formulated using the procedure developed by Wittenburg. The generic Melnikov function for the attitude motion of a gyrostat subject to small non-linear damping torques and small periodic torques is derived. The derivation is based on the chaotic theory for a 'one and half' degrees of freedom system established by Wiggins and Shaw. The conditions for the physical parameters at the onset of the homoclinic solutions are given in detail. The chaotic criteria are investigated using Melnikov's function. In particular, the conditions of the physical parameters (moments of inertia, damping coefficients, amplitudes and frequencies of external excitation, moments of momentum of wheels) that ensure the convergence of Melnikov's integral are also worked out. In order to acquire some knowledge of long-term behaviours of the chaotic attitude motion, the fourth-order Runge-Kutta numerical algorithms are utilized to simulate its dynamics. The numerical experiment shows that the chaotic motions of the gyrostat are bounded, non-periodic and sensitive to initial conditions. One of the practical mechanical models of the gyrostat is the artificial satellite. The attitude motion of the three-axis stabilized gyrostat satellite, whose torque-free motion is the homoclinic orbits, will oscillate chaotically when it is subjected to the appropriate external disturbances.     

Analytic generation of workspace using the robot kinematics

When designing workplaces, controls should be placed within the reach of an operator's arm or foot for guaranteeing effective performance. In designing a workplace which must cater to a wide range of operator size, it might be sufficient to plan only for the ‘average person’. Static arm reach measurements which are taken in conventional, standardized positions provide necessary information, but they cannot be applied to dynamic situations directly. To obtain reach envelope or workspace of the human body not by direct measurement but by analytic generation, data on range of joint motion(ROM) are required as an input. The purposes of this research are to measure the range of motion of two degrees of freedom for Korean young males, and to propose an approximate algorithm to generate the workspace of the human body including foot and trunk motion, in which joint mobility of two degrees of freedom motion are considered. The robot kinematics was employed to represent the human body as a multi-link system.     

基于RFID车辆信息交换系统的射频模块设计

基于RFID车辆信息交换系统,给出了系统中射频模块的参数选择、节点设置和软硬件设计方法,同时给出了硬件各模块的选择、上位机工作方式以及下位机控制程序的设计方法。为了保证对系统的精准性数据保护,设计中采取了CRC方法和LRC方法,并确定了传输协议。     

Forward dynamical analysis of flexible multibody systems using system-level model reduction

Fast simulation (e.g., real-time) of flexible multibody systems is typically restricted by the presence of both differential and algebraic equations in the model equations, and the number of degrees of freedom required to accurately model flexibility. Model reduction techniques can alleviate the problem, although the classically used body-level model reduction and general-purpose system-level techniques do not eliminate the algebraic equations and do not necessarily result in optimal dimension reduction. In this research, Global Modal Parametrization, a model reduction technique for flexible multibody systems is further developed to speed up simulation of flexible multibody systems. The reduction of the model is achieved by projection on a curvilinear subspace instead of the classically used fixed vector space, requiring significantly less degrees of freedom to represent the system dynamics with the same level of accuracy. The numerical experiment in this paper illustrates previously unexposed sources of approximation error: (1) the rigid body motion is computed in a forward dynamical analysis resulting in a small divergence of the rigid body motion, and (2) the errors resulting from the transformation from the modal degrees of freedom of the reduced model back to the original degrees of freedom. The effect of the configuration space discretization coarseness on the different approximation error sources is investigated. The trade-offs to be defined by the user to control these approximation errors are explained.     

Invariant surface and motion estimation from sparse range data

In this paper, we present a system for the estimation of the surface structure and the motion parameters of a free-flying object in a tele-robotics experiment. The system consists of two main components: (i) a vision-based invariant-surface and motion estimator and (ii) a Kalman filter state estimator. We present a new algorithm for motion estimation from sparse multi-sensor range data. The motion estimates from the vision-based estimator are input to a Kalman filter state estimator for continuously tracking a free-flying object in space under zero-gravity conditions. The predicted position and orientation parameters are then fed back to the vision module of the system and serve as an initial guess in the search for optimal motion parameters. The task of the vision module is two-fold: (i) estimating a piecewise-smooth surface from a single frame of multi-sensor data and (ii) determining the most likely (in the Bayesian sense) object motion that makes data in subsequent time frames to have been sampled from the same piecewise-smooth surface. With each incoming data frame, the piecewise-smooth surface is incrementally refined. The problem is formulated as an energy minimization and solved numerically resulting in a surface estimate invariant to 3D rigid motion and the vector of motion parameters. Performance of the system is depicted on simulated and real range data.