The measurement theory and realization of a novel magnetostriction liquid-level sensor

A novel magnetostriction liquid-level sensor which is centered on the C8051F005 was designed. On the base of measuring the output signal, the single chip processor adjusts the gain of the variable gain amplifier by D/A converter, so the amplitude of output signal is steady within the whole range. The difference of the invigorative pulse and the response pulse is calculated by the field programmable gate array using the high frequency counter. When the clock frequency is equal to 50 MHz, the time precision arrives at 1/50 μs. The experimental results show that the precision of the novel magnetostriction liquid-level sensor is ±2 mm, the influence of variable amplitude is overcome. The measurement error is reduced by the field programmable gate array using the high frequency counter to calculate the difference of invigorative and response pulse.