For a standard base ball pitch what is the range of pitcher's arm acceleration while throwing I am trying to get it with accelerometer and I am getting 80 ms-2?

 

Some info here
https://sites.sas.upenn.edu/biol438/files/pitching.pdf
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3811736/

an more... Use Google..

 

Sounds about right for a slow pitch. My take is 34 ms, 18 in forearm, 90 deg. of acceleration, 90 MPH pitch.

 

8G seems reasonable, without any calculations, just intuition.

 

Thanks for the reply guys. @mcgyvr & @wayneh this paper is what has got me confused http://resenv.media.mit.edu/pubs/papers/2006-06-IMU-Baseball.pdf . In the abstract you can see "The IMUs recorded 60.4g’s of acceleration at the shoulder and 83.0g’s of acceleration at the wrist. Acceleration over 100g’s was documented at the hand." That looks like way too high to me.

 

Well, I was doing a back of the napkin calculation and came up with ~50G. I didn't put it in my post because I didn't have time to verify it.

My approach was to guess the distance over which the ball is accelerated (maybe 6? feet, probably more for a pro) and the final velocity (90mph or 132 ft/sec) and then just calculate what the average acceleration had to be, assuming it was constant.

60G at the shoulder seems unlikely to me.

 

I did the calculation with these assumtions:

2m arc of the throwing hand. Constant acceleration. Speed of 90mph.

It came to 400 m/s^2 or 40.8g.

This article confirmed my calculation, after the fact:

http://www.science20.com/science_20/science_baseball_what_fastest_pitcher_can_throw-51797

Bob