共查询到20条相似文献,搜索用时 187 毫秒
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加速度计是惯性导航系统的核心部件,通常加速度计的输出信号为模拟电流,为便于导航计算机对采集数据解算处理,需经过I/F(电流/频率)转换电路。为满足某惯导系统对大比例系数加速度信号采集转换的要求,在经典I/F电路的基础上结合FPGA+A/D设计了一种比例系数大于90000脉冲/(s·mA),量程为6mA的电流频率转换电路,同时转换电路支持串口输出。通过对该大比例系数I/F转换电路的温度特性、线性度、零位稳定性等指标的测试,表明该电路性能良好,有利于进一步拓展应用范围。 相似文献
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金属振动陀螺是一种低成本、长寿命的新型简并模谐振陀螺,其结构相对简单,加工相对容易实现。但是,金属材料的温度系数和热膨胀系数大,其受到温度变化的影响明显,温度漂移对器件最终性能的影响较为明显。因此,对金属振动陀螺进行温度补偿,可以显著提高器件性能指标。建立了金属振动陀螺的温度模型,确定环境温度对器件谐振频率和零位偏移的影响关系。研究发现,金属振动陀螺谐振频率的温度系数具有超高线性度,可以替代温度传感器的作用,直接用谐振频率作为温度补偿量的输入。基于温度模型,进一步建立了温度漂移补偿模型,计算金属振动陀螺谐振频率的温度系数和零位偏移的温度关系,并对金属振动陀螺的温度漂移进行补偿。通过实验结果验证,金属振动陀螺谐振频率的温度系数为0.0536 Hz/℃,线性度达3.4×10~(-6),零位偏移和温度呈二次曲线关系,温度补偿后,金属振动陀螺的随机漂移可降低65%左右。 相似文献
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介绍一种使用电流传感器的交流电流-直流电压(ACI/DCV)转换电路,具有与被测电路隔离、体积小、测量范围广、线性度好等特点。 相似文献
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为降低变频器供电引起的永磁同步电机(PMSM)电磁振动噪声,首先理论分析了变频器引入的PMSM振动噪声源,然后利用MATLAB/Simulink建立仿真模型,通过dSPACE进行编译并控制一台PMSM,比较了随机开关频率调制技术和死区补偿技术降低振动噪声的优缺点,提出一种混合随机开关频率死区补偿技术。试验结果表明,此方法综合随机开关频率调制技术和死区补偿技术的优点,能降低逆变器引入电流谐波引起的中低频振动噪声和逆变器开关频率与电流谐波相互作用引起的高频振动噪声。 相似文献
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为了提高雷达成像的质量.得到高分辨率的SAR图像就必须保证有精确的运动补偿方法来校正运动误差对成像的影响。提出了一种基于惯导数据INS的视线方向位移误差的补偿方法,采用了低精度低成本的INS.对此部分的原理及实现进行了深入的建模分析和推导,并给出仿真结果。结果表明,基于惯导进行运动补偿时低精度也可满足要求。 相似文献
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旋转捷联惯导系统采用旋转调制误差补偿技术对陀螺仪和加速度计误差进行调制,可以提高系统导航精度。文章借助捷联系统基本误差方程,简要分析了旋转调制误差补偿的机理;通过对几种典型IMU旋转方案的分析和仿真,验证了旋转调制误差补偿技术的有效性并比较了不同旋转方案的特点。 相似文献
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压电陶瓷叠层作动器的迟滞蠕变非线性特性严重影响了控制系统的稳定性及动态跟踪精度。针对其迟滞蠕变非线性补偿控制问题,提出了一种高精度动态补偿压电陶瓷叠层作动器非线性特性的自适应混合补偿控制方法,即迟滞蠕变前馈补偿与自适应滤波反馈补偿结合的前馈-反馈混合控制方法。采用改进的Prandtl-Ishlinskii(Modified Prandtl-Ishlinskii,MPI)模型对压电陶瓷叠层作动器迟滞蠕变非线性特性进行精细化建模,并得到其逆补偿模型进行前馈补偿。根据前馈补偿误差,采用自适应滤波反馈控制对输入信号进行实时调控,实现对压电陶瓷叠层作动器的迟滞非线性及lg(t)型蠕变特性的实时精确补偿控制。数值仿真与实验结果表明,相比于常规前馈迟滞蠕变补偿,所提出的自适应混合补偿控制方法可以有效降低压电陶瓷叠层作动器的迟滞补偿误差,极大提高了迟滞蠕变非线性动态跟踪精度以及自适应性。 相似文献
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Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square(LMS) algorithm is proposed. According to the method, the initial values of adaptive filter's weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter's expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision. 相似文献
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To overcome the influence of the nonlinear friction on the gimbaled servo-system of an inertial stabilized platforms(ISPs) with DC motor direct-drive, the methods of modeling and compensation of the nonlinear friction are proposed. Firstly, the inapplicability of LuGre model when trying to interpret the backward angular displacement in the prestiction regime is observed experimentally and the reason is deduced theoretically. Then, based on the dynamic model of direct-drive ISPs, a modified LuGre model is proposed to describe the characteristic of the friction in the prestiction regime. Furthermore, the state switch condition of the three friction regimes including presliding, gross sliding and prestiction is presented. Finally, a composite compensation controller including a nonlinear friction observer and a feedforward compensator based on the novel LuGre model is designed to restrain the nonlinear friction and to improve the control precision. Experimental results indicate that compared with those of the conventional proportion–integration–differentiation(PID) control method and the PID plus LuGre model-based friction compensation method, the dwell-time has decreased from 0.2 s to almost 0 s, the position error decreased to 86.7%and the peak-to-peak value of position error decreased to 80% after the novel compensation controller is added. It concludes that the composite compensation controller can greatly improve the control precision of the dynamic sealed ISPs. 相似文献
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设计提出了 1种针对高光谱图像分类任务的 3D-MSCNN模型。在 PCA降维的基础上,利用 3D空谱特征提取网络和 2D多尺度特征提取网络实现高光谱图像特征提取,充分发挥高光谱图像空谱信息价值,增强对不同尺度地表覆盖的表达能力。最后,利用 Softmax分类损失函数实现高光谱图像分类任务。实验结果表明,本文算法在 In. dian Pines和 Pavia University数据集上都取得了较好的分类效果。与 CD-CNN、3D-CNN、SS-Net和 HybirdSN等方法相比,本文算法能够有效提升总体精度、平均精度和 Kappa系数等客观评价指标。 相似文献