Primitive Archer

Main Discussion Area => Bows => Topic started by: Del the cat on June 07, 2014, 05:43:56 pm

Title: Arrow acceleration from an Oak bow
Post by: Del the cat on June 07, 2014, 05:43:56 pm
Not really sure where to post this, but I found it interesting. I'd just done a rough calculation of the acceleration of an arrow from my 70# longbow I came up with 289g which sounded bonkers, so I searched the web and found this quirky article.
They fix an accelerometer onto an arrow (yes it adds weight and screw the draw length, but they still recorded 200g ! ::))
http://www.gcdataconcepts.com/arrow.html (http://www.gcdataconcepts.com/arrow.html)
I liked the fact that it's a wooden bow and a practical test, not a load of maths.
(Mind they can't shoot worth a damn :laugh:)
Del
Title: Re: Arrow acceleration from an Oak bow
Post by: Badger on June 07, 2014, 06:04:46 pm
  Del, I have been waiting for that gadget to get just a tad smaller so I can hook it up to flight arrows. Cool isn't it?
Title: Re: Arrow acceleration from an Oak bow
Post by: Don Case on June 07, 2014, 06:22:18 pm
No wonder arrows bend!!!!
Title: Re: Arrow acceleration from an Oak bow
Post by: mikekeswick on June 08, 2014, 03:16:01 am
0 - 100 mph + in a split second.....is some serious G's however you look at it!
Title: Re: Arrow acceleration from an Oak bow
Post by: Don Case on June 08, 2014, 12:31:54 pm
I had a 55 Chevy that was close to that ;) ;) ;)
Title: Re: Arrow acceleration from an Oak bow
Post by: Badger on June 08, 2014, 01:46:35 pm
http://www.eetimes.com/document.asp?doc_id=1279599

Del, I thought you were talking about this one, check it out.
Title: Re: Arrow acceleration from an Oak bow
Post by: Del the cat on June 08, 2014, 03:07:20 pm
Yeah cool, I'd like one of those to play with.
Are you in/were you in electronics too? If not, ignore the rest of this!

I'm semi retired and can't keep up with all the newfangled stuff. I had to learn a completely new microcontroller for my last project (plus a new pcb layout package and a programming language I'm not used to >:(.... I hate C with a passion, I'd rather work in assembler :). (Old school sums me up!) >:(... never again. I was climbing up the slippery learning curve for months.
Gimme bows and arrows any day.
Each year I say, I'll retire next year, but working a 2 day week pays the utility bills and gives Mrs Cat a couple of days without me under her feet.
Del
Title: Re: Arrow acceleration from an Oak bow
Post by: JacksonCash on June 09, 2014, 02:37:43 am
Badger- That was an interesting article. I wonder if they could get a shock sensor with a higher threshold now that a couple years have gone by... From the article Del linked, that 150g limit might not be enough!
Title: Re: Arrow acceleration from an Oak bow
Post by: Carson (CMB) on June 09, 2014, 03:42:20 am
cool article.  So a roughly 800 grain arrow from a 38 lb bow reaches 200 Gs.  I wonder what kind of Gs a 400 grain arrow would achieve from the same bow.  Can we assume actual forces are approaching 400 Gs or is there some log-arithmetic involved?