针对新型惯性执行机构磁悬浮控制力矩陀螺(Magnetically suspended control moment gyro,MSCMG),基于金字塔构型开展卫星平台敏捷机动控制地面闭环试验研究,以验证MSCMG的姿态控制性能。首先基于MSCMG搭建卫星平台控制地面试验系统,建...针对新型惯性执行机构磁悬浮控制力矩陀螺(Magnetically suspended control moment gyro,MSCMG),基于金字塔构型开展卫星平台敏捷机动控制地面闭环试验研究,以验证MSCMG的姿态控制性能。首先基于MSCMG搭建卫星平台控制地面试验系统,建立数学模型;接着针对气浮台外界扰动抑制及大角度敏捷机动控制问题,基于变参数滑模控制设计姿态控制算法,采用鲁棒伪逆方法进行MSCMG群框架角速度分配;并针对MSCMG的特性对框架角速度和角加速度进行了限幅,开展闭环控制试验研究。试验结果表明,采用MSCMG进行气浮台姿态稳定控制实验,可以实现姿态稳定度优于5×10^(-4)(°)/s,且在实现30°/15 s的机动指标时,MSCMG框架角速度具有良好的跟踪性能,且磁悬浮转子在输出大力矩时仍然保持稳定悬浮,具有较强的鲁棒性。通过地面闭环试验验证了MSCMG作为姿控执行机构的优异性能,为其未来进一步应用研究奠定基础。展开更多
We report that a metal-dielectric-metal cavity with a perforated top metallic filn shows a remarkable polarizationselective collimation effect through reflection on the perforated film.According to simulations,such pl...We report that a metal-dielectric-metal cavity with a perforated top metallic filn shows a remarkable polarizationselective collimation effect through reflection on the perforated film.According to simulations,such plasmonic cavities can achieve nearly perfect absorption (R<1.5%) of a transverse magnetic (TM) wave at an optimized incident angle while nearly perfect reflection (R~100%) at normal incidence.A very wide incident angle range (approximately 15°-65°) is found to exhibit a high absorption ratio exceeding over 70%.In contrast,for a transverse electric (TE) wave,the plasmonic cavities remain highly reflective (R~100%) regardless of the incident angles.We elucidate that this polarization- and angle-dependent behavior arises from an even-order (N =2) horizontal Fabry-Perot (FP) resonant mode inside the plasmonic cavity.This effect may find potential applications for angle filtering of polarized divergent light beams in optics.展开更多
文摘针对新型惯性执行机构磁悬浮控制力矩陀螺(Magnetically suspended control moment gyro,MSCMG),基于金字塔构型开展卫星平台敏捷机动控制地面闭环试验研究,以验证MSCMG的姿态控制性能。首先基于MSCMG搭建卫星平台控制地面试验系统,建立数学模型;接着针对气浮台外界扰动抑制及大角度敏捷机动控制问题,基于变参数滑模控制设计姿态控制算法,采用鲁棒伪逆方法进行MSCMG群框架角速度分配;并针对MSCMG的特性对框架角速度和角加速度进行了限幅,开展闭环控制试验研究。试验结果表明,采用MSCMG进行气浮台姿态稳定控制实验,可以实现姿态稳定度优于5×10^(-4)(°)/s,且在实现30°/15 s的机动指标时,MSCMG框架角速度具有良好的跟踪性能,且磁悬浮转子在输出大力矩时仍然保持稳定悬浮,具有较强的鲁棒性。通过地面闭环试验验证了MSCMG作为姿控执行机构的优异性能,为其未来进一步应用研究奠定基础。
基金Supported by the National Basic Research Program of China Grant No 2009CB929300the National Natural Science Foundation of China under Grant Nos 10804019,11174055 and 11174057,Shanghai Science and Technology Committee(No 09dj1400103).
文摘We report that a metal-dielectric-metal cavity with a perforated top metallic filn shows a remarkable polarizationselective collimation effect through reflection on the perforated film.According to simulations,such plasmonic cavities can achieve nearly perfect absorption (R<1.5%) of a transverse magnetic (TM) wave at an optimized incident angle while nearly perfect reflection (R~100%) at normal incidence.A very wide incident angle range (approximately 15°-65°) is found to exhibit a high absorption ratio exceeding over 70%.In contrast,for a transverse electric (TE) wave,the plasmonic cavities remain highly reflective (R~100%) regardless of the incident angles.We elucidate that this polarization- and angle-dependent behavior arises from an even-order (N =2) horizontal Fabry-Perot (FP) resonant mode inside the plasmonic cavity.This effect may find potential applications for angle filtering of polarized divergent light beams in optics.
