Design and Construction of a Low-Cost Arduino-Based pH Sensor for the Visually Impaired Using Universal pH Paper

This technology report outlines the design and construction of a simple Arduino-based pH sensor using universal pH paper; it can be assembled for less than $40 and is ideal for use in laboratory classrooms teaching students with visual disabilities. The device is simple to construct and suitable for adoption in school chemistry laboratories because of its miniature size, user-friendliness, and flexible coding. The Arduino-based pH sensor allows the visually impaired to use and interpret universal pH paper in measuring pH, which could not be previously attempted. A change in color of the indicator paper, as detected by the RGB color sensor, generates a distinctive audible tone that corresponds to the pH value being measured. This device can function as a helping hand in the learning process by facilitating a more exciting and meaningful laboratory exercise experience not only for the visually impaired but also for their normal-sighted peers.