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2016.02.29: Dudes. I am very excited for this. I've done a video test of the physics, written lecture notes, and written the script. This one is going to be fun. I apologize right at the beginning for the surfeit of instructions I have for you; I am just trying to mitigate issues long term.

• ​Here is the script for the entire video, the script for just your portion, and the lecture notes. [note all are drafts]
  • Script Legend:
    • (voice over) In other words, you can read the script, as long as you don't sound dead pan robotish.
    • [instructions]
    • ...    is a pause in the narration. This allows me to increase the time between phrases if necessary.
  • FYI: Stage left/right is relative to the person on the stage.
• Don’t feel like you have to say exactly what I have written. Say whatever comes naturally, as long as the physics is correct, i’m happy.
• I will need a signed video release form from everybody who appears in the video, please.
  • If they are a minor, the parents need to sign instead.
• For our purposes a digital speedometer on the car is better than an analog one.
• I don’t care what the exact numbers are, I think it really depends on the physical geometry of your parking lot, etc. Although,
  • Please drive the car at more than 10 km/hr so we can have 2 significant digits and not just one.
  • Ditto for the angle, I'd like it to be more than 10 degrees. (Unlike my example)
• I will take as much video of the process you can provide me with. More video is better. 😀
• It just occurred to me that I keep referring to a "roundabout" in my script, etc., however, you probably won't be driving around a roundabout. I'll fix the script, etc. when I go to film.
• I will need at least seven videos (multiple takes of each is better):
  1. Person introducing the video of the pendulum and car.
  2. Top view from Drone with car in motion.
  3. Pendulum with car in motion.
  4. Pendulum with car still. (Pendulum still and vertical)
  5. Speedometer with car in motion.
  6. Everybody dancing and singing at the end to Emre's song!
  7. Everybody saying their names so I know how to say them. I have messed up the pronunciation of names before; I'd like to avoid that.
     
• Here are the measurements I need:
  
  1. Radius of the circle the pendulum describes. (You will need to measure with a linear measuring device.)
     
  2. Speed of the car. (I will get from video #5.)
     
  3. Angle of the pendulum. (I will get from videos #3 and #4.)
     

For videos #1 & #6:

• Please use a tripod.
• I have Sean in the script, however, it can be whomever you like.
• You can have as many people as you’d like with you while you are saying your lines.
• #6 specifically. Please have Emre's song playing so I can sync the audio/video with the song.

For video #2, the drone:

• Have the car moving in a counterclockwise direction from above (+z direction using the right hand rule).
• Use cones or something to delineate the circle the car is going to drive in. Clearly, it needs to be a constant radius circle.
• I will need markers for video stabilization and tracking.
  1. At the center of the circle. Some sort of contrasting color object. Perhaps a cone?
  2. On the car. Perhaps a large, brightly colored piece of duct tape on the roof approximating where the pendulum is?
• Film with whatever the highest resolution you can that has 30 frames per second.
• The circle the car describes should only take up two thirds of the width of the frame. Because the resolution of the film should be much higher than 1920x1080, I will be able to zoom in, center, stabilize and fisheye correct the video.

​Below is what I would like the pendulum videos 3 & 4 to look like:

• Pendulum Videos #3 & #4:
  • Notice the extreme swing of the pendulum. This is bad. Could you please have someone in the car while you drive it in the circle who can decrease the swinging of the pendulum? (I did this by myself which made it difficult). This is necessary for a better measurement of the angle and we need to approximate the acceleration in the y-direciton of the pendulum to be zero.
  • Please film from the back of the car. This, with the car moving in the counterclockwise direction from above will make the tension force in the in-direction to the left, which will mean we can review that the “in direction” is positive regardless of left/right up/down.
  • It would be nice if the string of the pendulum could be a bright, contrasting color.
  • You will need someone in the back of the car holding the camera still on a tripod. This is because I will overlay a video of the pendulum while the car is in motion with the vertical pendulum to measure the angle. (see picture to the right)
  • In order to overlay the two videos, the camera needs to not have moved between the two pendulum videos you film.
  • If someone isn't holding the tripod and preventing it from moving between takes. This might happen to you. (See video below). Oops.

For video #5, the speedometer:

• It may feel like cheating, however, the video doesn't have to be while the car is driving around the circle.
• It will be safer to film the speedometer while you drive in a straight line somewhere. Just make it the same speed as when you were driving in a circle.
• Please have the camera be stationary, otherwise it will move a lot in the video, which would be bad.
• It will end up looking similar to the speedometer 5:04 into the video below.

THANK YOU!!! I know it seems like a lot, however, I think this video will be really great when it is done. Please, read through all of this and contact me with whatever questions you have before you start filming.

​Jon