Desarrollo de prototipos para mejorar el proceso de enseñanza-aprendizaje de temas en el campo de la física: prototipo portable funcional para medir la velocidad con sensor ultrasónico.

Abstract

In this work, a low-cost functional portable prototype was designed and implemented to measure distance, speed, and acceleration of a car moving on an inclined plane by using an ultrasonic sensor. First, the hardware design was carried out, consisting of the structure and the electronic circuits. All the pieces of the structure were implemented with the selected electronic components. Among the main ones are the HC-SR04 ultrasonic sensor, optical sensors, and an LCD. The LCD was included in order to show distance and speed even without a computer. Then, the software was designed on Arduino IDE and LabVIEW. A graphical interface was created on LabVIEW to observe the measurement data. This interface has three pages: start (front page), data acquisition (configuration and real-time measurements), and main graphs (movement curves, theoretical curves, and the percentage error of the acceleration). The functionality of the prototype was verified by taking measurements and comparing them to theoretical calculations. The obtained errors are attributed to the resolution of the ultrasonic sensor, parameter measurement errors, and the estimations made. The low-cost characteristic of the prototype was demonstrated by comparing the total fabrication price with the commercial cost of the EPN reference equipment. A total saving of 85,20 % was obtained. Finally, a laboratory guide and a user’s manual were written to be able to perform a practice with the prototype named NNCart.