A new current feedback amplifier (CFA) based dual-input differentiator (DID) design with grounded capacitor is presented;its time constant (τo) is independently tunable by a single resistor. The proposed circuit yiel...A new current feedback amplifier (CFA) based dual-input differentiator (DID) design with grounded capacitor is presented;its time constant (τo) is independently tunable by a single resistor. The proposed circuit yields a true DID function with ideal CFA devices. Analysis with nonideal devices having parasitic capacitance (Cp) shows extremely low but finite phase error (θe);suitable design θe could be minimized significantly. The design is practically active-insensitive relative to port mismatch errors (ε) of the active element. An allpass phase shifter circuit implementation is derived with slight modification of the differentiator. Satisfactory experimental results had been verified on typical wave processing and phase-selective filter design applications.展开更多
研究空间柔性伸杆机构的振动抑制问题,提出一种基于伸杆机构自适应指令整形(Adaptive input shaper,AIS)与航天器本体输出反馈控制相结合的复合控制策略,基于经验传递函数估计方法(Empirical transfer function estimate,ETFE),建立最...研究空间柔性伸杆机构的振动抑制问题,提出一种基于伸杆机构自适应指令整形(Adaptive input shaper,AIS)与航天器本体输出反馈控制相结合的复合控制策略,基于经验传递函数估计方法(Empirical transfer function estimate,ETFE),建立最优指令整形器(Optimal arbitrary input shaper,OAIS)的自调整机制,得到改进的自适应指令整形器。以金字塔构型的单框架控制力矩陀螺簇(Single gimbal control moment gyros,SGCMGs)为本体执行机构,详细设计基于实时仿真机、PMAC实时运动控制板卡、SGCMGs等实物的半物理仿真试验平台。在考虑环境干扰力矩以及执行机构控制受限的情况下对控制方法进行半物理仿真试验验证。结果表明:与基于OAIS及无指令整形前馈控制的复合控制方法相比,提出的控制方法可有效抑制伸杆机构的低频振动,实现航天器本体姿态的精确跟踪和伸杆机构的高精度指向控制。展开更多
文摘A new current feedback amplifier (CFA) based dual-input differentiator (DID) design with grounded capacitor is presented;its time constant (τo) is independently tunable by a single resistor. The proposed circuit yields a true DID function with ideal CFA devices. Analysis with nonideal devices having parasitic capacitance (Cp) shows extremely low but finite phase error (θe);suitable design θe could be minimized significantly. The design is practically active-insensitive relative to port mismatch errors (ε) of the active element. An allpass phase shifter circuit implementation is derived with slight modification of the differentiator. Satisfactory experimental results had been verified on typical wave processing and phase-selective filter design applications.
文摘研究空间柔性伸杆机构的振动抑制问题,提出一种基于伸杆机构自适应指令整形(Adaptive input shaper,AIS)与航天器本体输出反馈控制相结合的复合控制策略,基于经验传递函数估计方法(Empirical transfer function estimate,ETFE),建立最优指令整形器(Optimal arbitrary input shaper,OAIS)的自调整机制,得到改进的自适应指令整形器。以金字塔构型的单框架控制力矩陀螺簇(Single gimbal control moment gyros,SGCMGs)为本体执行机构,详细设计基于实时仿真机、PMAC实时运动控制板卡、SGCMGs等实物的半物理仿真试验平台。在考虑环境干扰力矩以及执行机构控制受限的情况下对控制方法进行半物理仿真试验验证。结果表明:与基于OAIS及无指令整形前馈控制的复合控制方法相比,提出的控制方法可有效抑制伸杆机构的低频振动,实现航天器本体姿态的精确跟踪和伸杆机构的高精度指向控制。
