Mathematical Modeling of Ultrasonic Phased Array for Obstacle Location for Visually Impaired

Ultrasonic beam steering characteristics of phased array transducer is mathematically modeled to detect and locate the obstacle for the visually impaired. The main purpose of Beam steering is to steer the beam at a given angle to investigate the object along the beam direction. The effects of various transducer parameters on beam steering properties are studied and optimal phased array is simulated. The device is constructed using 40 KHz practically available ultrasonic sensors of 16mm dimension. The main objective in designing is to minimize the main lobe width, to eliminate the grating lobes and to suppress the side lobes. In this paper the geometric parameters such as, number of elements, inter-element spacing, steering angle and array aperture are considered and transducer array is mathematically analyzed. The radiation pattern of the results is shown by the polar plots. These polar plots are simulated using LabVIEW (Laboratory virtual instrument engineering workbench) developed by National Instrument, is a graphical Programming environment suited for high-level or system level design. Advantage of this approach is the flexibility and very rapid development time offered by this graphical programming software.