Patent ID: 9395230
Filing Date: 2016-07-19
CPC Classification: G01F

Claim Text:
1. A measurement system for determining a liquid fill level of a tank, comprising: a floating sensor configured to float on the surface of a liquid contained in the tank; at least three reference sensors mounted at a hull of the tank in a spatially fixed arrangement; and a control device configured to control the floating sensor and the reference sensors, wherein at least one of the floating sensor and the reference sensors is configured to emit an acoustic signal to the remaining sensors, wherein the remaining sensors are each configured to receive the emitted acoustic signal, and wherein the control device is configured to determine signal travelling times of the acoustic signal from the emitting sensor to the receiving sensor, to compute a spatial position of the floating sensor with respect to the reference sensors using the signal travelling times of the acoustic signal, to determine the liquid fill level on the basis of the computed spatial position of the floating sensor, to control a first one of the at least three reference sensors to emit a test acoustic signal which is received by a second of the at least three reference sensors, to determine a travelling time of the test acoustic signal between the first and the second one of the at least three reference sensors, and to compute a speed of sound in the tank using the travelling time of the test acoustic signal.