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根据液浮转子式微陀螺闭环驱动系统对转子转速测量的需求,提出了一种适用于悬浮转子式微陀螺的反电动势转速检测方法.根据楞次定律,永磁转子在附有检测线圈的定子中转动时,会切割磁感线感应出反电动势.对反电动势信号进行分析,即可测得转子的转速.由于检测线圈与驱动线圈共用定子铁芯,这种检测方法在降低定于结构复杂度的同时,也引入了矩形波驱动信号带来的毛刺干扰.干扰信号经过模拟低通滤波器衰减后,通过模数转换器转换为数字信号.该信号通过单片机上运行的过零检测算法处理后,即可得到当前转子的转速.测试结果表明,该转速检测系统在刷新率为4 Hz、转速达到5 000 r/min以上时,测量值的相对误差在0.3%以内,其非线性误差为0.41%,能够满足对悬浮转子式微陀螺转速进行检测的要求. 相似文献
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Perfluorinated alkyl silicone oil (PFASO) was successfully synthesized from N-ethyl-N- hydroxylethyl perfluorinated octane sulfonamide, succinie anhydride and amino silicone oil by esterification and amide reaction at moderate temperature in the presence of different catalysts. The chemical structure of the synthesized samples was characterized by Fourier transform infrared spectroscopy (FT-IR), the relative molecular mass(MM) and molecular mass distribution(MMD) of PFASO were tested by gel filtration chromatography(GFC). A commercial epoxy resin (DGEBA) was modified with PFASO, with the content of PFASO 1-5 phr. Thermo-gravimetric analysis (TGA), impact tests, scanning electron microscope (SEM) and water contact angle test were applied to provide accurate results on the thermal stability, toughness and hydrophobicity of PFASO/epoxy complex. The experimental results reveal that epoxy resins can be successfully modified by adding a small amount of as-synthesized modifiers via simple direct mixing, and verify that the as-synthesized modifier can improve the toughness and hydrophobicity of epoxy resin without sacrificing its thermal properties. 相似文献
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玻璃纤维增强氯氧镁复合材料力学性能研究 总被引:1,自引:0,他引:1
研究了玻璃纤维增强氯氧镁复合材料的制备,力学性能、影响力学性能的因素及其微观破坏机理。 相似文献