基于北斗导航通信技术的无人艇运动导航控制系统设计

为实现对无人艇行进器的运动控制,建立更加完善的导航应用策略,设计基于北斗导航通信技术的无人艇运动导航控制系统。以无人艇运动姿态研究作为切入点,在电机驱动器、电机测速模块的支持下,连接中央处理单元、电源模块、方位监测模块等硬件设备结构体,完成导航控制系统的硬件电路设计。在此基础上,确定与导航信息相关的短报文传输特征,通过协调接口数据传输协议应用格式的方法,定义通信协议加密对象的所属连接形式,完成对报文加密密钥参数的初步配置,实现基于北斗导航通信技术的无人艇运动导航控制系统的短报文加密处理。与基于惯性测量技术的导航控制系统相比,基于北斗导航通信技术控制系统的实际应用续航时间更长,在行进过程中始终能对无人艇运动方向进行精准化控制,可在完善行进器导航应用策略方面起到较强促进作用。     

Assessment of gastroesophageal reflux disease,musculoskeletal symptoms and quality of life in dentists

Background and aimGastroesophageal reflux disease (GERD) has been associated with sick leave, decreased work productivity and poor quality of life. Another possible cause for the development of GERD is the relationship with maintaining the posture in flexion of the spine. The aim of this study was: (1) to compare gastro esophageal reflux with musculoskeletal disorders and quality of life of dentists, (2) to evaluate the association between gastro esophageal reflux such as time in the profession, time working while sitting, musculoskeletal disorders and quality of life of dentists.Methods83 dentists (23 males and 60 females; average age 39.3 years old) participated in the study, who were evaluated for their time in the profession, sitting time, musculoskeletal disorders, quality of life (SF-12v2) and the GERD symptoms using the Frequency Scale for Symptoms of GERD (FSSG) questionnaire.ResultsThe results showed that the majority were female (72.3%) and sendentary (74.7%). A difference was found between the level of GERD with musculoskeletal disorders (p < 0.05) and quality of life (p < 0.05). An association was also found between GERD and working time (p < 0.01), sitting working time (p < 0.05), headache (p < 0.01) and quality of life (p < 0, 01).ConclusionThis study showed that there was an association with working time, sitting time, musculoskeletal disorders, quality of life and GERD in dentists.     

基于动作捕捉的汽车座椅坐姿自动化装配方法研究

针对汽车座椅坐姿自动化装配过程存在人体动作干扰等因素,提出基于动作捕捉的汽车座椅坐姿自动化装配方法。结合视觉动态特征分析方法,进行汽车座椅坐姿自动化装配的动作图像采集,对采集的汽车座椅坐姿动作图像进行降噪处理,采用分区域特征匹配方法进行汽车座椅坐姿动作图像的模板特征匹配,提取汽车座椅坐姿动作图像的边缘轮廓特征量,结合模糊像素区域性融合技术实现对汽车座椅坐姿自动化装配过程中的动作捕捉,根据动作捕捉结果进行汽车座椅坐姿的动态调节,实现汽车座椅坐姿自动化装配优化。仿真结果表明,采用该方法进行汽车座椅坐姿动作捕捉的性较高,动态调节能力较好,提高了汽车座椅坐姿自动化装配水平。     

基于视频和人体姿态估计的老年人摔倒监测研究

人口老龄化所带来的养老服务问题是现代社会面临的严重问题。例如在很多国家跌倒是造成老年人因伤致死的最大原因,因此如何对老年人进行自动摔倒监测就成为养老服务亟待解决的问题。目前,在室内摔倒监测领域中,基于可穿戴设备和基于环境传感器等主流摔倒监测方法面临着设备复杂、成本较高等问题。鉴于此,将人体姿态估计引入摔倒监测领域,提出了一种基于2D视频的摔倒监测算法。首先利用OpenPose数据集提取原始数据中人体关节的位置;其次利用这些具有增强特征的数据构建静态分类模型和动态分类模型;最后,在3个公共摔倒数据集上进行模型训练和摔倒监测的测试,取得了较好的效果,可以为摔倒监测相关研究提供一定的参考。     

基于六轴MEMS器件姿态测量系统

为了解决噪声和漂移等原因造成的误差不断累积的问题,针对陀螺仪的静态性能以及加速度计的动态性能,提出了一种利用六轴MEMS器件对照相机三脚架的稳定测量系统,介绍了MEMS器件的工作原理,介绍硬件系统和软件系统,完成了基于ADXR450陀螺仪和ADXL355加速度计的检测硬件系统设计,通过传感器获取角速度加速度信息,采用不同的滤波方式对输出结果进行了分析,比较卡尔曼滤波和一阶RC数字滤波;经比较,卡尔曼滤波实时性更好,一阶RC滤波动态响应更好;实验证明,系统静态下更适用于一阶滤波,计算出姿态测量角度误差在0.104°以内,得到理想的姿态信息,能有效地提高检测目标姿态的精度。     

A Review of :“Leu Accidents du Travail.” By JACQUES LEPLAT et XAVIER CUNY. (Paris: Presses Universities de France, 1974.( [Pp.128. £0·00.

Police officers spend large amounts of time performing duties within a police cruiser and report a high prevalence of musculoskeletal problems. This study evaluated the effects of driver seat and duty belt design on posture, pressure and discomfort. Ten male and 10 female university students attended two sessions involving simulated driving in a standard police seat (CV) and an active lumbar support (ALS) seat. Participants wore a full duty belt (FDB) or reduced duty belt (RDB) in each seat. Lumbar postures, driver-seat and driver-duty belt pressures and perceived discomfort were measured. Gender × Seat interactions were found for pelvic (p = 0.0001) and lumbar postures (p = 0.003). Females had more lumbar flexion than males and were more extended in the ALS seat (?9.8 ± 11.3°) than CV seat (?19.8 ± 9.6°). The FDB had greater seat pressure than the RDB (p < 0.0001), which corresponded to increased pelvis discomfort. This study supports the use of an ALS seat and RDB to reduce injury risk associated with prolonged sitting in police officers.

Practitioner Summary: Police officers report a high prevalence of musculoskeletal problems to the lower back, associated with prolonged driving and further investigation is needed to reduce injury risk. This simulated driving study investigated seat and duty belt configuration on biomechanical measures and discomfort. Seat design had the greatest impact, regardless of gender and males benefited more from a reduced belt configuration.     

车用摄像头锁紧装置姿态调整系统设计

针对汽车倒车用摄像头在装配过程中对锁紧装置的自动化装配能够实现锁紧装置的姿态调整要求,设计了姿态自动调整系统。采用激光照明和PIN-FET （Field Effect Transistors）混合集成光电接收器配合定时器联合工作,对锁紧装置的姿态进行识别,并通过翻转装置对锁紧装置的姿态进行调整,送由机械手完成锁紧装置的拾取与安装,实现车用摄像头的自动锁紧装配。结果表明,基于激光照明和PIN-FET混合集成光电接收器配合定时器联合工作的姿态自动调整系统,正确率高,锁紧装置在运送过程中即可完成识别,有效提高安装效率。     

基于姿态定位算法的水下电缆监测系统

针对海洋科学考察中连接设备的水下电缆无法观测的现状,该文提出了一种基于姿态定位算法的水下电缆监测系统。系统采用两片V,11SCA60单轴倾角传感器对电缆不同位置处的双轴倾角数据进行采集,并通过CAN总线传送到水下主控CPU,数据经打包后由同轴电缆或光电复合缆传送至甲板上位机,通过姿态定位算法在上位机中完成电缆姿态监测。实验证明该系统可准确地定位电缆姿态并能够对危险操作和异常状态及时做出预警,为设备水下投放提供保障。     

Designing a Posture Analysis System with Hardware Implementation

Posture analysis is an active research area in computer vision for applications such as home care and security monitoring. This paper describes the design of a system for posture analysis with hardware acceleration, addressing the following four aspects: (a) a design workflow for posture analysis based on radial shape and projection histogram representations; (b) the implementation of different architectures based on a high-level hardware design approach with support for automating transformations to improve parallelism and resource optimisation; (c) accuracy evaluation of the proposed posture analysis system, and (d) performance evaluation for the derived designs. One of the designs, which targets a Xilinx XC2V6000 FPGA at 90.2 MHz, is able to perform posture analysis at a rate of 1,164 frames per second with a frame size of 320 by 240 pixels. It represents 3.5 times speedup over optimised software running on a 2.4 GHz AMD Athlon 64 3700+ computer. The frame rate is well above that of real-time video, which enables the sharing of the FPGA among multiple video sources.

基于人体姿态检测的体感滑板控制系统设计

为改善电动滑板的易操纵性,设计了基于人体姿态检测的体感滑板控制系统.该系统由人体姿态检测与滑板主控两大部分组成.首先,通过实验,分析了人体以不同姿态驾驶滑板时MPU6050传感器采集到的加速度和角度的数据变化规律.在此基础上,确定了驾驶滑板时,识别人体姿态改变的方法.最后,制作了人体姿态检测与滑板控制电路,并编写了相应的控制程序.调试结果表明,该系统响应准确,达到了设计要求.