Extracting data from a smartphone video with OriginPro

Students in the Department of Physics and Astronomy at Washington State University took videos with a cell phone and are using OriginPro’s Video Data Extractor application to digitize the data, frame by frame, for analysis and graphing in the classical mechanics course.

Context of the experiment

In their recent publication “Collecting data with a Mobile Phone: studies of mechanical laws such as energy and momentum conservation” [1], Professor Mark Kuzyk and Maxx Hart present a series of experiments performed in a classical mechanics course. A video recording of a billiard ball collision was made on a smartphone, and Origin’s Video Data Extractor application was used to digitize the position of the billiard ball, frame by frame.

Similar laboratory experiments use data collected from a moving cell phone [2], but Kuzyk presents a simpler alternative by recording video of moving objects, without using a strobe [3], and digitizing this data with OriginPro’s video extractor. 

Other video extraction tools exist, such as Vernier and Tracker, but Kuzyk says, “We chose to use the video extractor with Origin because it includes sophisticated data analysis software…and creates professional quality graphics. The other solutions require exporting the data for more sophisticated analysis. 

“We chose to use the video extractor with Origin because it includes sophisticated data analysis software…and creates professional quality graphics. The other solutions require the data to be exported for more sophisticated analysis.” 

Results of the experiment

For the experiments, the motion of a billiard ball before and after a collision with another ball was recorded on a cell phone. The students checked the frame rate of the phone by taking video of a clock with a second hand. In the Video Data Extractor application, students used the measurements of the actual pool table to set the axis scale. The students then clicked several times on the center of the pool ball before moving to the next frame. In this way, the video extractor uses these multiple measurements for a single location to return the average coordinate and standard error.

“These data could then be further analyzed and visualized to study conservation of energy and momentum in collisions, rolling and sliding friction, angular momentum in the presence of sliding torque, and dissipative forces.”

The velocity of a cue ball as a function of time (points) and five-point smoothing (red curve).

The cue ball is hit in region a and hits the eight ball in region c.

The other regions correspond to the cue ball sliding (b and d) and rolling (e).

The inset shows a plot of the distance versus time and piecewise quadratic fits, with intersections represented by large purple dots.

Mobile phone-based data collection is fun and engaging for students because it can incorporate many real-life examples. What’s more, it comes at a time when universities have been forced to adapt to distance and hybrid teaching models.  “We are very grateful to Professor Kuzyk for working with us to develop the Video Extractor app, and we hope it will be useful to the broader scientific community.” – OriginLab.

To go further…

Download a trial version of OriginPro today to try this application for yourself. If you would like to use the OriginPro Coursework license with your students, please visit our academic licensing page. 

References :
[1] M. Hart, & M. G. Kuzyk, “Collecting data with a mobile phone: Studies of mechanical laws such as energy and momentum conservation“, Am. J. Phys. 88(11), 948-957(2020). doi:10.1119/10.0001686
[2] J.C. Castro-Palacio, L. Velazquez-Abad, M.H. Gimienez, and J.A. Monsdoriu, “Using a mobile phone acceleration sensor in physics experiments on free and damped harmonic oscillations“, Am. J.Phys. 81, 472 (2013)
[3] J.C. Williamson, R.O. Torres-Isea, and C.A. Kletzing, “Analyzing linear and angular momentum conservation in digital video of puck collisions,” Am. J. Phys.,68, 841 (2000).

Notes :
Images are reproduced from M. Hart, & M. G. Kuzyk, “Collecting data with a mobile phone: Studies of mechanical laws such as energy and momentum conservation”, Am. J. Phys. 88(11), 948-957(2020). doi:10.1119/10.0001686, with the permission of the American Association of Physics Teachers.

 Source et illustrations : originlab.com
Traduction : ritme.com