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sdkfz 238 APC from Remember Eureka

Started by buzzbomb, September 12, 2010, 04:16:36 AM

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rickshaw

#15
I had an idle few minutes at work (OK about an hour of the Boss's time) and decided to look into how big a sitting soldier is.   Came up with this (all measurements in centimetres):

heel-kneeButtock-headtotal height seated1/35
Max.49.7105154.74.42
Shoulder Width
Max.163
Knee-buttock rearFoot-lengthtotal from back of seat to big toe, seated1/35
Max.71 30.5 101.52.9
(1)


sources:
(1)US Army, Anthropometry of US Military Personnel (Metric), Pentagon, 1991.
Australian Defence Force,  MIS 872, ADF Aircrew and Crewstation Anthropometry, Canberra, 2007
Tim Olds, T., Ross, J., Blanchonette, P.,  and Stratton, D., 'Fitting the Man to the Machine: The ADAPT Project', Australian Defence Force Journal, Issue No. 172, 2007.

Now, just in case you're not aware, Anthropometry is the measurement of the human body.  The US Army study is a mine of information and has data dating back to 1918 in it.  Yes, we are getting taller - about 1 cm a decade.  We are also getting larger, about again 1 cm a decade in shoulder width.  I utilised the 1946 data and the 2007 Australian data.  The difference was marginal.

The total height seated is of a man sitting with his thighs at right angles to his calves.  So, a vehicle would need a passenger compartment which was at least 155cm tall.  It could actually be slightly lower if the seat was lowered slightly, perhaps 10cm?  Each passenger requires at least 100cm width (the 160cm width is exceptional and only 10% at most of soldiers would need that width).  The distance between the front of each row of seats and that of the row opposite must be an absolute minimum of about 60 cm (maximum length of feet measured was 30 cm), I'd recommend about a metre actually.

So, that shows you the minimum requirements for an APC compartment IMO.



If anybody wants a copy of the US Army study its available here:

http://quanterion.com/Documents/Documents.asp?ArgVal=6241 in PDF format and its free to download.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

Weaver

Interesting stuff Rickshaw. :thumbsup:

I wonder how practical a 155cm ceiling would be in other respects, after all, you don't just sit there, you have to get up and move through the vehicle to get out too, and holding a weapon to boot. Having said that, the lowest ceiling I found was 1.6m (Steyr 4K4FA and 4K7FA), so it must be doable. I'm sure I've seen a pic somewhere of one of these vehicles fully loaded with troops, and it's pretty tight. The sitting posture was way different from the "standard" one you describe too.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

rickshaw

Looking through the stats is fascinating.  It took them 4 hours each to measure a sample of over 100,000 soldiers in 1946.  From it, seats, uniforms, boots, gasmasks, you name it was designed.   Interestingly, the Australian study adopts a different approach - they measured the cockpits of aircraft and armoured vehicles using a laser system and then worked out who could fit them and now use the data to select crewmen/pilots/etc. so that they aren't too big or too small to utilise all the controls.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

buzzbomb

Really fascinating research Rickshaw..Having myself spent enough time bumping around in M-113 and M557.. they can never be big enough. :thumbsup:

anyhoo.. back to the model
almost there most of the basic construction finished.. just the vehicle commanders hatch to go.. I intend to drill that out

Aboveish shot


Comparison with the Sdkfz 251.. really the Whiff is not that much bigger length wise but a fair bit higher, although most of that is ground clearance
Rear shot comparison

side by side


Seeing the ground clearance.. I now have to add a step it would appear

So next is the painting stage

Cheers All

redram


ChernayaAkula

Cheers,
Moritz


Must, then, my projects bend to the iron yoke of a mechanical system? Is my soaring spirit to be chained down to the snail's pace of matter?

Fulcrum

Looks awesome!!!

(sorta looks like a LAV-though a German-designed ww2 version :o :thumbsup:)
Fulcrums Forever!!!
Master Assembler

buzzbomb

Quote from: Fulcrum on September 18, 2010, 01:59:32 AM
(sorta looks like a LAV-though a German-designed ww2 version :o :thumbsup:)

Gotta agree the further along I got the more it did.. still..

I was on a roll with this one and calling it a wrap.. it may or may not get another quick overall dust coat, before being consigned to the cabinet after a trip to club so some JMN can do a "what the...." ;D






Thanks to Rickshaw for the great inspiration on this one and it gave me something to do with an old kit that I had robbed parts from.
Also thanks to all the folks on the boards for the great support and feedback

Cheers

Gondor

That's one dam good looking model, well thought out and very plausible. If a JMN asks you can always say it was a losing entry in the German Army's next generation troop carrier in 1944 or some such thing.

Gondor
My Ability to Imagine is only exceeded by my Imagined Abilities

Gondor's Modelling Rule Number Three: Everything will fit perfectly untill you apply glue...

I know it's in a book I have around here somewhere....

Steel Penguin

very convincing, and looks "right". an alternative is to have it made for some one post war perhaps as repatriations, or to throw a curve ball have it as a "reel" model for a hollywood blockbuster. that will drive the JMNs doubly mad.
the things you learn, give your mind the wings to fly, and the chains to hold yourself steady
take off and nuke the site form orbit, nope, time for the real thing, CAM and gridfire, call special circumstances. 
wow, its like freefalling into the Geofront
Not a member of the Hufflepuff conspiracy!

Weaver

Love it - it looks like a racing APC..... ;D :wub:

First class job - well done!  :thumbsup:
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

NARSES2

Do not condemn the judgement of another because it differs from your own. You may both be wrong.

rickshaw

Nice.  The hatch looks a little small compared to the man or the man is a little large compared to the hatch. I think the MG would get in the way of closing it.   Apart from that, quite well executed.  I'm glad some people are being inspired by my little story.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

ysi_maniac

Will die without understanding this world.

ChernayaAkula

Just excellent!  :bow: This looks very believable. Like something that really was.
Cheers,
Moritz


Must, then, my projects bend to the iron yoke of a mechanical system? Is my soaring spirit to be chained down to the snail's pace of matter?