Classification of normal gait from pathological gait as then can be used as indicator of falling among subjects requires the correct choice of sensor location in the insole. Such a flexi force- sensor can be used unde...Classification of normal gait from pathological gait as then can be used as indicator of falling among subjects requires the correct choice of sensor location in the insole. Such a flexi force- sensor can be used underneath foot to measure vertical ground reaction force. To start with, the most relevant information (parameters) that can characterize the recorded signals are extracted from the vertical ground reaction force signals. Then Receiver Operating Characteristic curve is used to evaluate the features upon 8 sensors underneath each foot located at different locations. To confirm results obtained, features are passed upon a chosen classifier, in this paper K-nearest neighbors algorithm is chosen. Results show that the sensor located at the inner arch of the sole of the foot (i.e. at the mid foot) holds the most relevant information needed for better classification compared to other sensors.展开更多
In the present paper, the ground reaction force （GRF） acting on foot in slow squat was determined through a force measuring system, and at the same time, the kinematic data of human squat were obtained by analyzing ...In the present paper, the ground reaction force （GRF） acting on foot in slow squat was determined through a force measuring system, and at the same time, the kinematic data of human squat were obtained by analyzing the photographed image sequences. According to the height and body weight, six healthy volunteers were selected, three men in one group and the other three women in another group, and the fundamental parameters of subjects were recorded, including body weight, height and age, etc. Based on the anatomy characteristics, some markers were placed on the right side of joints. While the subject squatted at slow speed on the force platform, the ground reaction forces on the forefoot and heel for each foot were obtained through calibrated force platform. The analysis results show that the reaction force on heel is greater than that on forefoot, and double feet have nearly constant force. Moreover, from processing and analyzing the synchronously photographed image sequences in squat, the kinematic data of human squat were acquired, including mainly the curves of angle, angular velocity and angular acceleration varied with time for knee, hip and ankle joints in a sagittal plane. The obtained results can offer instructive reference for photographing and analyzing the movements of human bodies, diagnosing some diseases, and establishing in the future appropriate mathematical models for the human motion.展开更多
To eliminate the load weight limit of carrier rockets and reduce the burden on support structures,in-orbit assembly is a key technology to make design of scattering a large diameter telescope into submirror modules,wh...To eliminate the load weight limit of carrier rockets and reduce the burden on support structures,in-orbit assembly is a key technology to make design of scattering a large diameter telescope into submirror modules,which requires smooth operation of assembly robots,and flexible force control technology is necessary. A ground demonstration system is presented for in-orbit assembly focusing on flexible force control. A six-dimensional force/torque sensor and its data acquisition system are used to compensate for gravity. For translation and rotation,an algorithm for flexible control is proposed. A ground transportation demonstration verifies accuracy and smoothness of flexible force control,and the transportation and assembly task is completed automatically. The proposed system is suitable for the development of in-orbit assembly robots.展开更多
海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效...海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效手段。本文从海岸带独特性和遥感技术优势出发,借助Web of Science和CNKI数据库,分析了海岸带遥感国内外研究现状,探讨了海岸带遥感所面临的科学技术问题,综述了研究进展,明确了机遇与挑战,讨论了未来发展方向。本文可为科学认识海岸带遥感中存在的问题,把握海岸带遥感发展方向提供参考。展开更多
采用微波技术测量位移的方法,设计了一种基于开口环谐振器(Split Ring Resonator,SRR)的二维线性位移微波传感器。传感器由定子与动子两部分构成,其中定子由两组不同尺寸的SRR耦合一条传输微带线构成,动子采用单面覆铜的FR-4介质基板制...采用微波技术测量位移的方法,设计了一种基于开口环谐振器(Split Ring Resonator,SRR)的二维线性位移微波传感器。传感器由定子与动子两部分构成,其中定子由两组不同尺寸的SRR耦合一条传输微带线构成,动子采用单面覆铜的FR-4介质基板制成。动子二维移动时两个SRR的谐振频率将发生变化,传输零点也产生对应偏移,从而建立起位移和传输零点的关系。此外通过对SRR加载缺陷地结构,提高了检测灵敏度。经电磁建模和仿真,传感器在1 GHz至3.2 GHz范围内产生两个传输零点,可在x和y方向表征0~6 mm的位移,灵敏度分别为122 MHz/mm和82 MHz/mm。制作并测试了传感器实物,实测与仿真的数据基本吻合,证实了该传感器设计的有效性。展开更多
文摘Classification of normal gait from pathological gait as then can be used as indicator of falling among subjects requires the correct choice of sensor location in the insole. Such a flexi force- sensor can be used underneath foot to measure vertical ground reaction force. To start with, the most relevant information (parameters) that can characterize the recorded signals are extracted from the vertical ground reaction force signals. Then Receiver Operating Characteristic curve is used to evaluate the features upon 8 sensors underneath each foot located at different locations. To confirm results obtained, features are passed upon a chosen classifier, in this paper K-nearest neighbors algorithm is chosen. Results show that the sensor located at the inner arch of the sole of the foot (i.e. at the mid foot) holds the most relevant information needed for better classification compared to other sensors.
基金supported by the National Natural Science Foundation of China (10702048 and 11102126)Natural Science Foundation of Shanxi (2010021004-1)
文摘In the present paper, the ground reaction force （GRF） acting on foot in slow squat was determined through a force measuring system, and at the same time, the kinematic data of human squat were obtained by analyzing the photographed image sequences. According to the height and body weight, six healthy volunteers were selected, three men in one group and the other three women in another group, and the fundamental parameters of subjects were recorded, including body weight, height and age, etc. Based on the anatomy characteristics, some markers were placed on the right side of joints. While the subject squatted at slow speed on the force platform, the ground reaction forces on the forefoot and heel for each foot were obtained through calibrated force platform. The analysis results show that the reaction force on heel is greater than that on forefoot, and double feet have nearly constant force. Moreover, from processing and analyzing the synchronously photographed image sequences in squat, the kinematic data of human squat were acquired, including mainly the curves of angle, angular velocity and angular acceleration varied with time for knee, hip and ankle joints in a sagittal plane. The obtained results can offer instructive reference for photographing and analyzing the movements of human bodies, diagnosing some diseases, and establishing in the future appropriate mathematical models for the human motion.
基金Supported by the National Natural Science Foundation of China(No.11672290)
文摘To eliminate the load weight limit of carrier rockets and reduce the burden on support structures,in-orbit assembly is a key technology to make design of scattering a large diameter telescope into submirror modules,which requires smooth operation of assembly robots,and flexible force control technology is necessary. A ground demonstration system is presented for in-orbit assembly focusing on flexible force control. A six-dimensional force/torque sensor and its data acquisition system are used to compensate for gravity. For translation and rotation,an algorithm for flexible control is proposed. A ground transportation demonstration verifies accuracy and smoothness of flexible force control,and the transportation and assembly task is completed automatically. The proposed system is suitable for the development of in-orbit assembly robots.
文摘海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效手段。本文从海岸带独特性和遥感技术优势出发,借助Web of Science和CNKI数据库,分析了海岸带遥感国内外研究现状,探讨了海岸带遥感所面临的科学技术问题,综述了研究进展,明确了机遇与挑战,讨论了未来发展方向。本文可为科学认识海岸带遥感中存在的问题,把握海岸带遥感发展方向提供参考。
