A novel velocity measurement method based on contact image sensor

An acoustic tube was developed and applied using the volume velocity measurement method for the prediction of constant exterior engine noise. Using accelerometers to measure engine surface vibration is a difficult task, especially for places such as the exhaust manifold. The proposed method is as follows: an acoustic tube containing a microphone is set at a given distance from the engine and measurements are made in such a way that the whole engine surface is covered. Exterior engine noise at a certain distance from the vehicle was predicted by using the measured volume velocity values and propagation characteristics. The predicted results agreed well with previously experimental values.

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Velocity measurement for moving surfaces using spatial filtering method based on area image sensor

Optik ◽

10.1016/j.ijleo.2014.08.084 ◽

2014 ◽

Vol 125 (24) ◽

pp. 7136-7139 ◽

Cited By ~ 6

Author(s):

Xin He ◽

Xiaoming Nie ◽

Jian Zhou ◽

Xingwu Long

Keyword(s):

Velocity Measurement ◽

Spatial Filtering ◽

Image Sensor ◽

Filtering Method

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Research on inter-satellite ranging and velocity measurement method based on Doppler frequency measurement

2012 2nd International Conference on Consumer Electronics, Communications and Networks (CECNet) ◽

10.1109/cecnet.2012.6202115 ◽

2012 ◽

Author(s):

Lijing Wang ◽

Xue Li ◽

Yikang Yang ◽

Lei Liu

Keyword(s):

Velocity Measurement ◽

Measurement Method ◽

Doppler Frequency ◽

Frequency Measurement

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Acoustic Emission Wave Velocity Measurement of Asphalt Mixture by Arbitrary Wave Method

Applied Sciences ◽

10.3390/app11188505 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8505

Author(s):

Jianfeng Li ◽

Huifang Liu ◽

Wentao Wang ◽

Kang Zhao ◽

Zhoujing Ye ◽

...

Keyword(s):

Acoustic Emission ◽

Wave Velocity ◽

Velocity Measurement ◽

Measurement Method ◽

Asphalt Mixture ◽

Low Frequency ◽

Noise Signal ◽

New Wave ◽

Ae Signal ◽

First Arrival

The wave velocity of acoustic emission (AE) can reflect the properties of materials, the types of AE sources and the propagation characteristics of AE in materials. At the same time, the wave velocity of AE is also an important parameter in source location calculation by the time-difference method. In this paper, a new AE wave velocity measurement method, the arbitrary wave (AW) method, is proposed and designed to measure the AE wave velocity of an asphalt mixture. This method is compared with the pencil lead break (PLB) method and the automatic sensor test (AST) method. Through comparison and analysis, as a new wave velocity measurement method of AE, the AW method shows the following advantages: A continuous AE signal with small attenuation, no crosstalk and a fixed waveform can be obtained by the AW method, which is more advantageous to distinguish the first arrival time of the acoustic wave and calculate the wave velocity of AE more accurately; the AE signal measured by the AW method has the characteristics of a high frequency and large amplitude, which is easy to distinguish from the noise signal with the characteristics of a low frequency and small amplitude; and the dispersion of the AE wave velocity measured by the AW method is smaller, which is more suitable for the measurement of the AE wave velocity of an asphalt mixture.

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