Design and Implementation of a Wireless Fluid Level Display System Using Ultrasonic Sensing Technique

The wireless fluid level indicator comprises a sensing and transmitting circuit for detecting and transmitting the levels of fluids from a container to the receiving circuit which receives and displays the amount of the measured volume. This has been achieved using an ultrasonic sensor (HC-SR04), a firmware (PIC16F648A/PIC16F876A microcontroller programmed in C/assembly languages), an encoder (HT12E) and a radio frequency (RF) transmitter transmitting at a bandwidth of 433MHz to an RF receiver interfaced with a decoder (HT12D), liquid crystal display (LCD) and a Buzzer. The device when tested measured water levels and transmitted same over a distance of up to 98.5 meters in open areas and up to 50 meters in highly obstructed areas. The average response time was also estimated to be 0.1 second. As a contact-less depth detection system, the device finds useful applications in measurement of fluid levels in homes and industries where concentrates, table water, transmission oils are produced, without affecting the chemical or physical properties of such substances-an advantage over the contact methods used in fluid level detection.

Aims: To design and implement a wireless microcontroller based fluid level display system using ultrasonic sensing method.

Study Design: By encoding the Transmitter module to sense and detect the amount of water level, while the decoder module decodes the received data and display the result.

Place and Duration of Study: Department of Physics, University of Agriculture Makurdi, Benue State, Nigeria, between November 2018 and April 2019.

Methodology: An RF transceiver, encoder/decoder (HT12E/HT12D), a 2x16 Liquid display module, 4MHz crystal oscillator, a buzzer and other peripherals were interfaced to two 8-bit controllers; PIC16F648A and PIC16F876A. The controllers were programmed in C/Assembly languages to enable effective communication of the system. The system was then calibrated to read and transmit water level values from a 30-centimeter deep tank over a distance of 1.0 - 98.5 meters.

Results: The system was tested to have maximum sensitivity over a distance of 98.5 meters in non-obstructed areas and 50 meters in obstructed areas. The average response time was also estimated to be 0.5 seconds.

Conclusion: The design and implementation of a wireless fluid level display system using ultrasonic sensing technique has been successfully done. The system workability is suitable for deployment and usage in domestic and industrial purposes.