Video analysis of objects in motion

Logger Pro is the preferred software package for years 10-12, since it interfaces very well with many of the data recording devices that we have including pH sensors, CO₂ probes, motion sensors, etc. However, it can take quite a bit of time to analyse all of the videos from the inclined plane experiment since each frame needs to be tracked as the cart slowly moves across the frame - repeat this for each trial, and then repeat again for each new height elevation of the ramp.

To speed up the process, you can use another software app called Tracker. This has a feature where it can 'autotrack' a feature in your video over time. To install Tracker:

1. Download tracker from this website (physlets.org/tracker/), and then click on the appropriate link at the top of the page that matches your computer (if you are a Mac, then pick Mac OSX, likewise for those on Windows).
2. You need at least Java 1.6 to run/install it, and Quicktime Player (Mac has quicktime by default).
3. To 'open' the installation package on your Mac, you will need to Ctrl+click on the .pkg file to allow you to open it. 

This video tutorial takes you through how to use Tracker to track a cart rolling down an incline plane - once you get the hang of it, it should only take 1-3 minutes to analyse one video, so it can be pretty quick. I still advise that you analyse at least one video (pick a fast one; less points) in Logger Pro, and paste a screenshot of the process into your prac report:

• as part of your communication for your method - that is, how you analysed the video data to obtain acceleration
• as part of your communication for your results section - a sample to show how you calculated those values. 

The process is much the same except Logger pro requires you to click on 'try fit' when you are applying a 'curve fit'. This will then provide you with the coefficients in the same manner as Tracker does.

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