Women It's that time of year again...(science fair)

[gymluvr33]

So it is time once again to turn in my science fair proposal. Last time I got some great help and advice from you guys (thanks!) and I was hoping for some more help I have an idea of what I want to do, but no clue how to go about doing it or if it is even realistic. It is common knowledge that landing in a pit or off tumble trak into a resi pit is easier on your joints and bones than tumbling on floor. I want to quantify that somehow. I was thinking by measuring the force of landing a double back on each surface, but I’m not really sure how to measure it. I’ve been reading about accelerometers, but I have absolutely no idea what I’m looking for. Anyway, if anyone has experience with something like this or ideas of what to do (or even ideas for alternate projects if this isn’t realistic) then it would be greatly appreciated! Thanks

 

[Deleted member D3987]

that is very expensive equipment. you might need to check your nearest college, 2 or 4 year, and they might have that equipment. i highly doubt they will let that equipment out of the lab, but possibly they will help you set it up to use. i can tell you that the force on a landing of a double back is the equivalent of jumping from a 2 story (approx 20 feet) building.

in order to perform the test, you would have to have the testing equipment, a computer, a floor and a gymnast. kinda looks like this:

Scrutiny on the Spring Floors - YouTube


this would all have to be expanded so that the gymnast can perform the skill. the force plates would be under the foam where they punch, and again under the surface that you want to test. as far as i know, i don't believe you would be able to use a loose foam pit. but a mat, a floor or resi would be able to be used. this is all pretty complex stuff, so you would want to ask someone at the college by you for their help. someone in the bio-mechanics or bio-engineering lab. maybe you can grab a graduate student looking for some applied research hours and would be happy to hep you as it would help them also. send along any questions if you have them and i'll help best i can.

 

[wallinbl]

A little math/physics and it might be simpler than dunno is making it. If you can get a hold of a high speed video camera (as in 1000 fps), you may be able to solve this. You might be able to rent one of those or borrow one.

The force your body is absorbing comes from mass x acceleration (f=ma). What you need to know is how fast the body was going when it contacted the surface (floor, mat, etc) and how long it took to stop. Recording a landing on a high speed camera can tell you how fast the gymnast was going when she hit the floor (speed), as well as how long after contact with the floor/mat until the floor/mat was fully compressed and the gymnast's downward motion came to a stop. In order to go from that speed to a full stop requires acceleration. You can get the gymnast's mass from a scale (that gives you weight, but mass can easily be determined because you know gravity on earth).

Once you know the acceleration and have the gymnasts mass, you know the force.

You'd have a more complex problem determining the stresses on the skeleton (knees, vertebrae, etc) vs musculature, and you'd need serious equipment for that. But, for just determining the force on the body as a whole, you can use a camera and high school physics to get your answers.

If you want to get fancy and include flipping rather than just straight jumps, remember that you'll have to calculate the rotational velocity of the gymnast as well as the downward velocity. There are some computer programs that can assist with this if you have video to supply it, or you can simply time the flip (from the high speed video), calculate the radius of the gymnast's tuck, and get a reasonable approximation.

 

[gymluvr33]

Thank you both so much! So, amending my original idea a bit...if I just test my theory using straight jumps and the calculations you mentioned, wallinbl, then add a "practical" aspect at the end to prove my point where I do the calculations for an example (double back, back layout, front layout, etc) would that make sense? I think I can borrow a high speed camera and use the ideas from wallinbl's post and that should work for my project. Thanks again for your help!

Btw, that video was very cool...I would love to be able to do something like that! Unfortunately, I don't think that will ever happen, but I can dream, right?

 

[cbone]

I have nothing important to say here other than it's a cool project idea. Let us know how it goes.

 

[gymluvr33]

Thanks, I will

 

[Deleted member D3987]

A little math/physics and it might be simpler than dunno is making it. If you can get a hold of a high speed video camera (as in 1000 fps), you may be able to solve this. You might be able to rent one of those or borrow one.

The force your body is absorbing comes from mass x acceleration (f=ma). What you need to know is how fast the body was going when it contacted the surface (floor, mat, etc) and how long it took to stop. Recording a landing on a high speed camera can tell you how fast the gymnast was going when she hit the floor (speed), as well as how long after contact with the floor/mat until the floor/mat was fully compressed and the gymnast's downward motion came to a stop. In order to go from that speed to a full stop requires acceleration. You can get the gymnast's mass from a scale (that gives you weight, but mass can easily be determined because you know gravity on earth).

Once you know the acceleration and have the gymnasts mass, you know the force.

You'd have a more complex problem determining the stresses on the skeleton (knees, vertebrae, etc) vs musculature, and you'd need serious equipment for that. But, for just determining the force on the body as a whole, you can use a camera and high school physics to get your answers.

If you want to get fancy and include flipping rather than just straight jumps, remember that you'll have to calculate the rotational velocity of the gymnast as well as the downward velocity. There are some computer programs that can assist with this if you have video to supply it, or you can simply time the flip (from the high speed video), calculate the radius of the gymnast's tuck, and get a reasonable approximation.

i know nothing about high speed cameras. that's amazing. AND you sure have a command of THIS language as someone i know in CA that used to own a gym...

 

[cbifoja]

Good luck!

 

[wallinbl]

Just to follow up, I'd bet that if you talked to the physics teacher (even if you don't have a class with him/her) she/he would be happy to show you the formulas you'd need and how to take the measurements from the video. I know mine would have been all over it - she was among the best teachers I ever had.

 

[gymluvr33]

Just to follow up, I'd bet that if you talked to the physics teacher (even if you don't have a class with him/her) she/he would be happy to show you the formulas you'd need and how to take the measurements from the video. I know mine would have been all over it - she was among the best teachers I ever had.

That's a good idea, I'm not taking physics this year, but I have the physics teacher for AP Calculus, so I'll ask him after class today.

And thanks, Bella's mom