Extracting Data from a Mobile Phone Video in OriginPro

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 lab experiments performed in a Classical Mechanics course. Video recording of a cue ball collision was taken and the Video Data Extractor App in Origin was used as a tool to digitize the position of the cue ball, frame by frame.

One frame of the video used to study the collisions of billiard balls

Similar lab experiments use data collected from a mobile phone in-motion [2], however Kuzyk presents an easier alternative by recording video of objects in motion, without the use of a strobe [3], and digitizing this data with the Video Extractor.

Other Video Extractor tools exist, such as Vernier and Tracker, however Kuzyk says "We chose to use the Video Extractor with Origin because it includes sophisticated data analysis packages...and creates professional-quality graphics. The alternatives require that data be exported for more sophisticated analysis.”

For the experiments, the motion of a cue ball before and after a collision with another ball was recorded on a mobile phone. Students verified the frame rate of the phone by taking video of a clock with a second hand. In the Video Data Extractor app, measurements of the actual pool table were used to set the scale of the axes. Then students clicked the center of the cue ball multiple times before moving on to the next frame. The Video Extractor uses these multiple measurements for a single location to return the average coordinate and the standard error. As Kuzyk outlines in his paper, "This data could then be further analyzed and visualized to study energy and momentum conservation in collisions, rolling and sliding friction, angular momentum in the presence of slipping 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 struck in the region labelled 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 as a function of time and piecewise quadratic fits, with the intersections shown as large purple points.

Collecting data from a mobile phone is not only fun and engaging for students, since it can incorporate many real-life examples, but it comes at a time when universities have been forced to adapt to remote and hybrid teaching models. We are very grateful to Prof. Kuzyk for his work with us to develop the Video Extractor App, and hope it useful to the broader scientific community. Download a trial of OriginPro today to try this app 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.