measuring smash speed

**dimcorner** · 06-29-2012, 09:09 AM

I think you would need to get one of the Casio Exlim cameras or something of that nature that can do more than 60fps. The smash is pretty much done in less than 1 second so you need to capture as many frames as possible, especially during contact.

You basically need a frame with the contact point and a few more after that (I would say about 2 or 3 more). 100mph is almost 147 feet per second. that meas that in 1 frame of a 60fps video the shuttle should travel 2.45 feet. However because you are decelerating you might travel less, say 2 feet. That only puts you at 82mph or so. So about 5 inches of error will drop you quite a few MPH. That's also assuming you can measure down to the inches as well.

I would think you need something 120fps or higher to do a good calculation. I think you need something that can record the moment of impact and maybe about 1 ft or so in front of it.

One tricky way to do it would be to take a still picture right after impact. If you know your shutter speed you can measure the size of the blur and determine distance traveled. Harder to get a good image thou. Maybe use sound activated shutter?

**newbro** · 07-13-2012, 03:40 AM

Just a quick idea of mine. How about using just a sound recorder? You will of course need to be in a quiet location for this to work, and have to place certain object as smash target to gauge the distance the birdie travels. If you were able to capture the sound of the birdie's initial contact with the racket and final contact with the target, you can measure the time elapsed and with distance calculated before hand, roughly calculate how fast your smash is.

This is by no mean accurate, but at least give you an idea and a simple project to experiment with. You probably just need a laptop with a mic, so need to have any camera setup of any kind.

**Alapongtai** · 07-13-2012, 04:47 AM

Originally Posted by newbro

Just a quick idea of mine. How about using just a sound recorder? You will of course need to be in a quiet location for this to work, and have to place certain object as smash target to gauge the distance the birdie travels. If you were able to capture the sound of the birdie's initial contact with the racket and final contact with the target, you can measure the time elapsed and with distance calculated before hand, roughly calculate how fast your smash is.

This is by no mean accurate, but at least give you an idea and a simple project to experiment with. You probably just need a laptop with a mic, so need to have any camera setup of any kind.

interesting idea but not very realistic. you need a quiet place, but clubs are usually filled with noises. also, it involves acoustics of the place as well as what kind of string, string tension etc (i think). too many variables

I say we just steal those car speed measuring devices on the road that police depts put out lol

**dimcorner** · 07-13-2012, 06:19 AM

You are then just measuring average speed, in which you can probably do with a camera since fairly accurately then (60fps). Just as a note they used the baseball pitching radar gun at one of our tournaments and I was almost the highest speed (113mph I think). But I don't think it's accurate since some people that I feel smash considerably harder than me only did 109mph.