Abstract:
Experiments play a vital role in science education.
In high school physics, especially in mechanics, many
experiments are conducted where tracking a single or multiple
objects are required. In most situations students visually observe
the motion of objects and take the measurements. This manual
method is time consuming, generates higher error and incapable
of producing multiple readings rapidly. The research described
in this work introduces a simple mechanism to integrate
computer vision based tracking to enhance the quality of
measurements and to new ways of looking at experiments. The
case study consists of three standard experiments. In the first
experiment a motion of the simple pendulum was tracked. Using
computer vision students were able to obtain a correlation of 0.99
between the calculated period and the theoretical period. In
addition, it was possible to calculate the position and the velocity
of the bob more than 30 times during a single oscillation.
Students were able to plot the extra data points for a better
understanding of the simple harmonic motion, which was not
possible in the manual method. Second experiment was focused
on measuring the terminal velocity of a ball moving through a
viscous medium. Final case study was on tracking multiple
particles in a moving fluid. In all three experiments computer
vision based system provided more accurate and higher number
of data points than the manual method. This helps students to
understanding the underline theory better. The tracking system
was consisted of a digital camera, image preprocessing sub
system, feature extraction subsystem, object identification
subsystem and data export subsystem. The system was
successfully tested on a normal PC which is cost effective to be
used in high schools. Based on the case studies it was concluded
that such systems can be used in high schools to improve the
quality of experiments conducted.
