Video Based Motion Analysis Tetyana Antimirova and Marina

Video Based Motion Analysis Tetyana Antimirova and Marina Milner-Bolotin, Department of Physics Faculty of Engineering, Architecture and Science Ryerson University OAPT Conference, May 22 -24, 2008 Ryerson University, Toronto

WHAT IS VIDEO-BASED MOTION ANALYSYS? n In Motion Video Analysis, experimental demonstrations or real-life events involving motion (roller-coaster rides, car race, sports events, objects falling, etc. ) are recorded on videos and later analyzed using Logger Pro or Video. Point software n The position data are collected from each time frame n Positions of objects in the video frame can be measured by pointing a mouse and clicking. n The data generated can be graphed, analyzed in spreadsheets, compared to theoretical models.

ADVANTAGES n Demonstrates real event (as opposed to idealized textbook end-of-chapter questions) n The data for problems/modeling come from the experiment n A Video Analysis mini-project presents a feasible cost effective alternative to live experiments. n Works whenever visible motion takes places

Data Acquisition and Analysis Software from Vernier (Logger. Pro) David Vernier www. vernier. com

Motion Video-Based Analysis Resources: Live. Photo Project http: //livephoto. rit. edu/wiki/ Patrick Cooney website http: //www. millersville. edu/~pjcooney http: //muweb. millersville. edu/~pjcooney/making-movies/

TETYANA’S FIRST TRY… Tetyana’s first attempt at motion video analysis at summer Activity. Based Physics Faculty Institute (ABPFI), Dickinson College, Carlisle, Pennsylvania, June 2007

EXAMPLES

Cart Going Forth and Back

Cart Going Forth and Back

Incline

Free Fall

VIDEO FROM “CONTEMPORARY GALILEO’S PROJECTILE” HOMEWORK (Courtesy of Activity Based Physics Group) Frame-by-frame traced trajectory

TWO-TRACKS DEMO FROM ONTARIO SCIENCE CENTRE Question: Two metal balls are released from the top point simultaneously. Which one will finish first?

HOMEWORK n Some of the traditional end-of-chapter problems can be converted into motion video analysis problems n Additional benefit: comparison of analytical solutions (whenever possible) with numerical solutions/modeling using real data

MANY STUDENTS FAIL TO RECOGNISE THE SIMILARITIES BETWEEN THESE SITUATIONS

TRADITIONAL END-OF-CHAPTER PROBLEM A package is dropped from the plane which is flying with a constant horizontal velocity of Va=150 ft/s. Determine the normal and tangential components of acceleration, and the radius of curvature of the path of motion just before the package strikes the ground R. C Hibbeler, (2006), “Engineering Mechanics”, Pearson

PROBLEM EXAMPLE Based on what you know about curvilinear motion, calculate the rate of increase of speed for the third last point of the trajectory (t=0. 917). Whenever possible, use real data from the movie. (was offered as a supplement to the ABP’s “Galileo’s Projectile II: Using Contemporary Techniques” assignment)

THE PROJECTILE PATH TRACED

HORIZONTAL MOTION

VERTICAL MOTION

VIDEO-BASED MOYION ANALYSIS n Potential to captivate and engage the students n Potential to use whenever the visible motion takes place

HANDS-ON PART Recoding our own video and inserting it into Logger. Pro n Analyzing movie using Logger. Pro n

THANK YOU!