Intro to LoggerPro Video

Tracking Motion Practice

Introduction:

The purpose of this activity is for you to learn how to create motion graphs using a video of an object's motion.

Information:

• In order to track the motion of an object on a video you must make sure the camera doesn't move at all during the filming of the object's motion
• You must track the same part of the object for its entire motion.
• In order to get accurate results you must make sure that there is one object in the video whose size is known. This object should be the same distance away from the camera as the object you are tracking.
• Toggle On/Off means to turn a feature on or off.
• In your graph "X" represents the horizontal position of your object and "Y" represents the vertical position of your object.
• In your lab book neatly sketch out the following two pictures with all the important buttons labeled.

Procedure: (Copy steps 1 through 10 into your lab book)

1. Open up LoggerPro and go to the "Insert Menu" and pick "Insert Movie". Navigate to the computer's desktop and pick the TwoCars movie you downloaded.

1. Click on the "Enable Video Analysis" button on the bottom right side of your movie. This will call up all the tools you need to work with your video.

1. Step 1 (Setting Scale): Click on the “Set Scale button on the right side of the movie. Click and drag a line from one end of the meter stick to the other and set that distance to 1.0 m. (If your green line is not appearing in the location it is suppose to appear, make sure Logger Pro is set on full screen. To do this click on the green button in the upper left corner of the Logger Pro Window).

1. Toggle off your scale so that green line you have made is no longer visible on your movie.
2. Step 2 (Pick Origin): Click on the “Set Origin” button on the right side of movie and then click on the point on the object you will be tracking. For this video you will be tracking the front tire on each car.

1. Toggle off the origin to hide the origin and the axes while working on your file.
2. Step 3 (Adding Points): Click on the “Add Point” button and then click on the point on the object you will be tracking. The movie should automatically advance one frame forward.
3. Now click on the same spot on the object to leave another mark. Continue this procedure to track the motion of the object until it is passed by the other
4. Now click on the square with both red and green dots. back up the movie until the second car enters the picture and track the motion of that car.
5. Step 4: When you are done adding points click on the “Select Point” button to avoid adding unwanted points to your graph.
6. Click on any portion of your graph that you can see behind the movie to bring the graph to the front and send the movie to the back.
7. Click on the title for the "Y-Axis" and set it to only display "X".

1. Neatly copy a large version of this graph into your lab book.
2. Break this graph into distinct sections based on changes that take place with the motion of the object. For each region tell if the object is at rest, moving with a constant speed, gaining speed, or losing speed.
3. Do a linear fit for the portions of the graphs when the cars were moving at a constant velocity.

Things to Include in Your Lab:

• Purpose
• Info including pictures of the interface with descriptions of the functions of each button.
• Enough procedure that in the future you know how to use the tracking motion feature of Logger Pro
• Neat copy of your graph of X vs. time with each section labeled with what was happening to each car in each part. Slope for linear parts.
• Give a least two sources of error in this lab and include a way to make these errors less likely to occur

(Thanks to Dolores Gende for this activity)