Carbon fiber oxidized by KMnO4 was combined with ethylene vinyl acetate（EVA） copolymer,the obtained composite shows a fine stability of thermal cycles and nearly unchanged switching temperature under thermal（cycles...Carbon fiber oxidized by KMnO4 was combined with ethylene vinyl acetate（EVA） copolymer,the obtained composite shows a fine stability of thermal cycles and nearly unchanged switching temperature under thermal（cycles）,at the same time negative temperature coefficient（NTC） phenomenon is eliminated.Solvent-extraction method is used to examine the interaction between EVA and CF and insolublity with the gel structure were found.The crosslinking network in the gel adsorb CF intensely which makes CF disperse in EVA uniformly,orientate consistently,combine with EVA tightly and shows the elimination of NTC phenomenon.The（switching） temperature of the composite in the heating process is not identical with that of the composite in the cooling process absolutely,but the temperatures in the above two processes are consistent with the outset of melting temperature and the end of crystallization temperature respectively.展开更多
The low resistance PTC ceramic thermistor material with excellent eleectricalproperties are successfully fabricated by raw materials at industrial range made in our country onthe study of its composition expression an...The low resistance PTC ceramic thermistor material with excellent eleectricalproperties are successfully fabricated by raw materials at industrial range made in our country onthe study of its composition expression and fabrication process by using the addition of Nb, La, Y,Ta , microstructure regulator BN and ASTL phase . The composition and its fabrication method arestudied. The relation of electrical properties of the PTC ceramic material to its compositionexpression and its related electrical properties are discussed展开更多
针对目前虚拟实验热触觉装置缺乏的现状,设计了一种基于PTC(Positive Temperature Coefficient)加热片的热触觉感知复现系统。该系统利用HTC VIVE的红外定位,将虚拟环境下热源的空间位置映射为现实环境下制热模块的空间位置。根据虚拟...针对目前虚拟实验热触觉装置缺乏的现状,设计了一种基于PTC(Positive Temperature Coefficient)加热片的热触觉感知复现系统。该系统利用HTC VIVE的红外定位,将虚拟环境下热源的空间位置映射为现实环境下制热模块的空间位置。根据虚拟实验中不同位置和不同温度的热源,使用两个步进电机控制热源的位置和方向,并提供4个自由度的热源定位方法;使用PID控制算法控制PTC加热片产生热风的温度,获得不同的热触觉感知。该系统以一种非接触式的触觉感知来呈现虚拟实验的热触觉,保证了热触觉产生的真实性。通过铝热反应虚拟实验,验证该系统的实用性,结果表明该系统的热触觉再现能够提高虚拟实验的真实感受,补偿触觉上缺失的热反馈。展开更多
文摘Carbon fiber oxidized by KMnO4 was combined with ethylene vinyl acetate（EVA） copolymer,the obtained composite shows a fine stability of thermal cycles and nearly unchanged switching temperature under thermal（cycles）,at the same time negative temperature coefficient（NTC） phenomenon is eliminated.Solvent-extraction method is used to examine the interaction between EVA and CF and insolublity with the gel structure were found.The crosslinking network in the gel adsorb CF intensely which makes CF disperse in EVA uniformly,orientate consistently,combine with EVA tightly and shows the elimination of NTC phenomenon.The（switching） temperature of the composite in the heating process is not identical with that of the composite in the cooling process absolutely,but the temperatures in the above two processes are consistent with the outset of melting temperature and the end of crystallization temperature respectively.
文摘The low resistance PTC ceramic thermistor material with excellent eleectricalproperties are successfully fabricated by raw materials at industrial range made in our country onthe study of its composition expression and fabrication process by using the addition of Nb, La, Y,Ta , microstructure regulator BN and ASTL phase . The composition and its fabrication method arestudied. The relation of electrical properties of the PTC ceramic material to its compositionexpression and its related electrical properties are discussed
文摘针对目前虚拟实验热触觉装置缺乏的现状,设计了一种基于PTC(Positive Temperature Coefficient)加热片的热触觉感知复现系统。该系统利用HTC VIVE的红外定位,将虚拟环境下热源的空间位置映射为现实环境下制热模块的空间位置。根据虚拟实验中不同位置和不同温度的热源,使用两个步进电机控制热源的位置和方向,并提供4个自由度的热源定位方法;使用PID控制算法控制PTC加热片产生热风的温度,获得不同的热触觉感知。该系统以一种非接触式的触觉感知来呈现虚拟实验的热触觉,保证了热触觉产生的真实性。通过铝热反应虚拟实验,验证该系统的实用性,结果表明该系统的热触觉再现能够提高虚拟实验的真实感受,补偿触觉上缺失的热反馈。
