Design of liquid level measurement system using multi sensor data fusion for improved characteristics and fault detection

Online validation of multi sensor data fusion based liquid level measurement technique using capacitance level sensor and ultrasonic level sensor is implemented in this work. The objectives of the proposed work is to calibrate level measurement system by fusing the outputs of fuzzy sets of Capacitive Level Sensor (CLS) and Ultrasonic Level Sensor (ULS) such that (i) sensitivity and linearity should be improved as compared to ULS, (ii) reduction of nonlinear characteristics like offset and saturation which persists in CLS, and (iii) detection and identification of faults in sensors if any. These objectives are achieved by using the Joint Directors of Laboratories (JDL) multi sensor data fusion framework in cascade to the outputs of both the sensor. The proposed liquid level measurement technique was subjected to testing with practical data and results show successful implementation of liquid level measurement system.