To carry out a specific measurement work, we must first consider the principle of the sensor, which needs to be analyzed after analyzing various factors. Because even if it is measuring the same physical quantity, there are many kinds of sensors available for selection. Which kind of sensor is more suitable, you need to consider the following specific problems according to the characteristics to be measured and the conditions of the sensor: the size of the range; The position of the measured position on the sensor volume; the measurement method is contact or non-contact; the signal extraction method, wired or non-contact measurement; the source of the sensor, domestic or imported, the price can withstand, or self-developed.
Generally, in the linear range of the sensor, it is desirable that the sensitivity of the sensor be as high as possible. Because only the sensitivity is high, the value of the output signal corresponding to the measured change is relatively large, which is beneficial to signal processing. However, it should be noted that the sensitivity of the sensor is high, and external noise that is not related to the measurement is easily mixed in, and is amplified by the amplification system, affecting the measurement accuracy. Therefore, the sensor itself should be required to have a high signal-to-noise ratio and minimize interference signals introduced from the outside.
The sensitivity of the sensor is directional. When the measured is a single vector, and its directivity requirements are high, other sensors with small sensitivity should be selected; if the measured multidimensional vector, the cross sensitivity of the sensor is required to be as small as possible.