A new type of mechanical rotation pulse measurement device is proposed

aiming at problem that ultrasonic and photoelectric sensors have poor ability to resist pollution and can’t realize water depth and water level detection at the same time. The measurement device points cylinder lifting device

clamping device and control device. In falling process of heavy hammer

the downward displacement

velocity

acceleration of heavy hammer can be obtained through real-time detection on output rotation pulse number of photoelectric encoder. Then the two falling acceleration mutation points of heavy hammer can also be founded when heavy hammer gets into the water and arrives at the solid-liquid interface in a reservoir. Thus the reservoir water depth

water level and precipitation material thickness can be calculated. The measurement result shows that the pollution resistance capability of the device is strong and the water depth measurement error of the device is less than 1 % when the weight of heavy hammer is 510 g and the sampling time interval is 0. 10 s.