Development of Experimental Equipment for Observation the Freefall, Royal Thai Naval Academy, Using a Simple Microcontroller and Smart Phone

Abstract

The objectives of the research is to develop an easy-to-use and, nevertheless, highly-accurate free-fall apparatus for Physics Experiment Laboratory. In the proposed design, a microcontroller was used for controlling the application of a vibration detector and an ultrasonic sensor to, respectively, measure time and height of a falling object. Contrary to most conventional designs which use a stopwatch to measure the time and measuring scale to measure the height of the falling object, the proposed design, instead, uses the vibration detector and ultrasonic sensor for improving accuracy. The measurement results can be displayed on the microcontroller’s screen or on a smartphone via the IoT equipment and a smartphone application, namely, Blynk.

The results have shown that the tested apparatus of free falling which was controlled by microcontroller, time detected by a vibration detector, and measuring the height of falling with an equipment detecting the reflection of frequency of sound waves, and displayed the result through smartphones has an accuracy of 98.57%.