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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?.
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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? • 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 VideoPoint software • The position data are collected from each time frame • Positions of objects in the video frame can be measured by pointing a mouse and clicking. • The data generated can be graphed, analyzed in spreadsheets, compared to theoretical models.
ADVANTAGES • Demonstrates real event (as opposed to idealized textbook end-of-chapter questions) • The data for problems/modeling come from the experiment • A Video Analysis mini-project presents a feasible cost effective alternative to live experiments. • Works whenever visible motion takes places
Data Acquisition and Analysis Software from Vernier (LoggerPro) David Vernier www.vernier.com
Motion Video-Based Analysis Motion Video-Based Analysis Resources: LivePhoto Project http://livephoto.rit.edu/ http://livephoto.rit.edu/wiki/ Patrick Cooney website http://www.millersville.edu/~pjcooney http://muweb.millersville.edu/~pjcooney/making-movies/
Tetyana’s first attempt at motion video analysis at summer Activity-Based Physics Faculty Institute (ABPFI), Dickinson College, Carlisle, Pennsylvania, June 2007 TETYANA’S FIRST TRY…
Frame-by-frame traced trajectory VIDEO FROM “CONTEMPORARY GALILEO’S PROJECTILE” HOMEWORK(Courtesy of Activity Based Physics Group)
Question: Two metal balls are released from the the top point simultaneously. Which one will finish first? TWO-TRACKS DEMO FROM ONTARIO SCIENCE CENTRE
HOMEWORK • Some of the traditional end-of-chapter problems can be converted into motion video analysis problems • 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)
VIDEO-BASED MOYION ANALYSIS • Potential to captivate and engage the students • Potential to use whenever the visible motion takes place
HANDS-ON PART • Recoding our own video and inserting it into LoggerPro • Analyzing movie using LoggerPro