OBJECTIVES:

• Investigate the dynamics of machines with the high-speed camera
• Investigate the dynamics of miscellaneous interesting things with the high-speed camera

BACKGROUND:
Have you ever wondered how that wind-up toy that you won at Chucky Cheese on your last birthday operates?  Or how a wave propagates through tissue after receiving a right hook to the gut?  Or the mechanics of an egg impacting the ground?  Do you want to settle that bet with your friend regarding the air-speed velocity of an unladen swallow?  Well, your chance to uncover these and other mysteries is here at last.

MATERIAL AND METHODS:
This is your section!  Your group must bring in two typed procedures detailing the setup, procedure, and what you're expecting to see.  One procedure is to investigate something mechanical and the other procedure is to investigate something you think would be interesting or fun.

MECHANICAL PROCEDURE:  Write a procedure to investigate a device, mechanism, contraption, contrivance, gismo, gadget, appliance or apparatus.  Along with your procedure, of course, you must bring in the item which we are to film.  Or, if you want, we can film something in the building (e.g., something in an instructional Lab), provided you get proper authorization, beforehand, from the powers that be.  Because this is the lab for Dynamics of Machines, try to bring something mechanical that has some dynamics involved (e.g., vibrations, deflections, deformations--you get the idea).  Ideas might include:

• Electric toothbrush or razor
• Blender (with something in it)
• Speaker
• Wind-up toy with fast action
• Exposed watch gears
• Exposed VCR guts

"SOMETHING INTERESTING" PROCEDURE:  Write a procedure to investigate something that would be interesting, fun, enjoyable, amusing, comical, droll, entertaining, or cool to see in super-slow-motion. 

• Something that breaks
• Something that explodes (within reason)
• Something borrowed
• Something blue

It is also possible to have a procedure to film something that's not an device/object (e.g., stupid human tricks).  If you choose to do this, you really need to be creative; don't let this be your cop-out alternative when you forget to bring something in!  Your TA will ridicule you in front of your classmates if he suspects that this is the case.  So, if you wish to save face and reduce the risk of being humiliated, it is suggested that you actually bring something to lab.

Check out Dr. Dave's gallery of high speed video clips for ideas.

There will not be a quiz this week.  Instead, your two typed procedures and the associated devices/items/objects will replace your quiz and lab summary grades.  You need to turn in only one set of procedures per group. Here are more details concerning what is expected in your procedures:

Describe how the camera should be setup (i.e., point-of-view, what part of the item to focus on, camera angle, frames per second, etc.). You don't need exact numbers; just something like, "About a foot away from the target, looking at the top face of the target at an angle of about 45 degrees below horizontal."

Describe what you expect to see and what kind of time frame the exciting event is supposed to occur in. Using the spring lab as an example, "The spring should vibrate at its longitudinal natural frequency. Because its natural frequency is about 100 Hz, the camera should be set to at least that many frames per second. 500 or 1000 fps should be able to capture multiple images in each oscillation--enough to experimentally measure the natural frequency."

Describe the procedure. "Nick will stick his neck out 20 degrees off vertical. After putting in his the mouth guard to protect his teeth from shattering, Ryan will get in the 'ready stance' for the crane. As soon as Ryan begins his wicked maneuver, trigger the camera to start recording. Ryan will then perform the crane, a la Karate Kid, to Nick's dismay (but willingly accepts in the name of science). Due to the ferocity of the blow, 10,000 fps should be used."

Of course, these are short descriptions. Your group should make it clear exactly what is to be done in your setup/procedure (no more than 20 pages, though ... just kidding).

If your group needs some kind of special provision (e.g., going outside, going to another room, need other equipment, etc.), email your TA to let them know so that we can prepare (mentally and physically). So, don't come to lab and say, "What do you mean there are no donkeys in the lab? We needed one for our mechanical procedure!" So, if you need to go outside of the lab or need something that's not in the lab, let us know (if you're in doubt, email anyway). The TAs will try to accommodate you somewhat, but remember: your group has to bring in the item to film and/or get permission to film something in another room (machine shop or other instructional lab).

You need to bring in everything you need to ensure safe, clean, and successful filming. For example, if water is involved, you need to bring containers with water, a catch basin to capture water, and rags or a mop to clean up splashed or spilled water. If things might break into small pieces or shatter, you should bring a hand broom and dust pan. If things need to be secured to a table, bring clamps. Etc.!

ADDITIONAL RESOURCES:

• Kodak Camera Setup
• Sample High-Speed Camera Videos