共查询到19条相似文献,搜索用时 46 毫秒
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一种空间圆形目标俯仰角的测量方法 总被引:1,自引:1,他引:0
俯仰角在许多领域都有着重要的应用,对其进行精确的测量就成为一个亟待解决的关键问题。分析了空间圆形目标的俯仰运动,并根据旋转轴是否通过其圆心将其分为两类。基于摄像机透视投影原理,提出了一种空间圆形目标俯仰角的测量方法,分别推导出了两种情况下俯仰角的计算公式。并通过实验,验证了该方法的可行性。该方法测量方便,计算精度较高,俯仰角测量绝对误差在0.2°以内,可以满足许多应用领域圆形目标俯仰角测量的要求。 相似文献
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本文介绍JW系列新型激光激光测微仪的结构,原理,特点,还介绍了利用该仪器在音箱质量检测,记忆合金伸缩特性等科研中对微振动及动态位移进行非接触测量的研究情况并对测量结果进行了分析。 相似文献
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本文通过分析惯性传感器无法准确测量动态倾角的缺点,提出一种数据融合算法,并分析参数a的取值对数据融合结果的影响,发现算法尽管能够抑制动态加速度的干扰,但波形存在过冲.最后利用系统辨识建立因果递归系统,消除过冲,弥补数据融合的缺点.实验结果表明,通过系统辨识对数据融合算法的优化,倾角传感器能够得到准确的动态倾角值. 相似文献
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三米激光丝杠动态测量仪是测量高精度丝杠的大型精密测量仪器,其测量控制系统利用计算机辅助测量技术(CAT),具有动态性、实时性和智能化特点,选用通用微机作为控制主机,用模块式的测量仪器组合,大大增加了整机的灵活性,满足了测量精度高测量范围大的要求,有效地提高了测量的可靠性和稳定性。 相似文献
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《Measurement》2015
The development and implementation of a portable eddy currents testing instrument with heterodyning based measurements is presented in this paper. The instrument is composed by a dedicated electronic measurement circuitry embedded inside a rugged tablet computer for control and visualization and that interfaces a small footprint planar eddy currents probe. A DDS waveform generator and a transconductance amplifier are used to drive the probe current. The probe output voltage is amplified up to 60 dB and down-converted to an intermediary frequency, which is then digitized. IQ demodulation of the digitized signal is used to obtain the real and imaginary components of the probe output and is computed in real time by the embedded digital signal processor and transmitted to the host computer by USB. The eddy currents testing instrument can be operated as a battery powered standalone device with post-processing and visualization capabilities which can be modified for specific applications without the need for hardware modifications. The system architecture, electrical characterization of the analog circuit, digital signal processing and visualization interface are described. The eddy currents inspection results of an aluminum sample with synthetic defects and friction stir welding joint samples, using this instrument are presented. 相似文献
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基于相关和最小二乘原理的光栅栅距动态测量 总被引:1,自引:0,他引:1
栅距是光栅位移精密测量的基准,测出栅距值是进一步提高位移测量精度的关键.根据光栅莫尔条纹的动态特性,提出在光栅传感器运动过程中将栅距量转换为时间量测量的新方法.首先基于相关原理测量莫尔条纹信号经过两个距离固定的光电转换器的时间延迟来获得传感器的运行速度,时延估计采用了小波自适应算法;其次基于最小二乘原理确定莫尔条纹信号的相邻两个最小值来获得光栅栅距所对应的时间;最后由运行速度与栅距所对应时间的乘积确定栅距值.实验结果表明对于20 μm栅距的光栅传感器测量误差小于0.08 μm,验证了方法的可行性. 相似文献
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A portable three-dimensional stylus profile measuring instrument 总被引:2,自引:0,他引:2
This paper describes the development of an inexpensive, portable three-dimensional (3-D) stylus-based surface profiler with a scan range of 4.5 mm × 5.5 mm and a maximum vertical range of 150 μm (limited by signal conditioning electronic range) with a resolution of better than 0.9 μm and a range of 30 μm with a resolution of better than 30 nm at the highest vertical sensitivity. The instrument occupies a volume with dimensions of approximately 75 × 75 × 40 mm (L × B × H) with scan speeds up to 0.5 mm s−1. Construction of instrument components from similar material results in a thermally balanced design with a reasonably low thermal coefficient of 0.27 μm K−1 and a first-order time constant of approximately 40 min. The stylus probe sensor has a free resonant frequency of 49 Hz and a low damping ratio of 0.006. When in stationary contact with a steel surface, this increases to above the transducer bandwidth of 900 Hz. Calibration of the probe sensor is achieved through direct comparison against a standard stylus gauge. Lateral calibration of the specimen carriage position has been assessed by the measurement of standard gratings and laser interferometry. Planar errors caused by the motion of the carriage have been assessed by measuring an optical flat and inferring deviation from a perfect plane as an indication of the worst-case error, which in this case, was 0.2 μm (P-V). The design and construction of the internal datum and the portability of the instrument to facilitate in situ measurement of components are emphasized. Images illustrating the surface mapping capabilities of the profiler are presented. 相似文献
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水声声压是声学测量中应用最广泛的参数,声学计量检定系统中对水听器声压灵敏度的校准有多种方法.传统的水声测试系统使用工业计算机及水声水池,体积相对庞大.伴随着新型器件、新材料和数据采集器的应用,利用比较法校准原理及声波导管理论,以嵌入式系统为核心,设计一种能够在普通密闭腔体内完成测试的便携式水听器测试仪.可以进行直流电阻、交流阻抗、灵敏度、极性测量,且具有扫频及自动校准功能,软件界面友好.对密闭声场的仿真及实测结果表明,该仪器测量以密闭声场代替水声水池,电压测量精度为0.5 mV,电压灵敏度级的测量精度高于0.8 dB,满足产品生产测试要求,应用前景良好. 相似文献