Audible Charts of Mathematical Functions

This article describes the implementation of a prototype educational mobile application for visually disabled students, prepared in the form of a research tool. This tool allows students to explore the features of polynomial functions by audibly analyzing their graphs. The core of the tool is to explore the graph of the drawn function. It is implemented using audio feedback that reflects the position of the indicator relative to the function graph line and the value of the nearest point on the graph. This type of sonification is performed through sound waves synthesized in real time with an amplitude that is a function of the distance of the indicator from the graph line. The research goal is to verify which of the feature parameters of the audio graph are most suitable for graph exploration. The following features of the graph sonifying oscillator can be analyzed: type (sinusoidal, square, triangular, sawtoothed), base tone, sound sampling frequency, buffer size, amplitude decay threshold. The above-mentioned parameters can be properly configured, adapting the sound of the charts to the features of the mobile device’s touch screen and the student’s hearing capabilities.