Date: Fri, 8 Aug 2008 20:51:55 -0600
Reply-To: Thomas Buese <tombuese@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Thomas Buese <tombuese@COMCAST.NET>
Subject: Re: [NVC] Engineers: quick and cheerful vibration analysis?
In-Reply-To: <489CD93F.6020909@gmail.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
On Aug 8, 2008, at 5:39 PM, Mike Elliott wrote:
> Mr B-Z,
>
> I have been sorting and packing for the past three months. I'm
> rounding
> the last turn of the racecourse, and am--even as I write this--
> taking a
> well-deserved break. This is like packing for a long backpacking
> trip, or
> a camping trip: I make lists, I sequence things. I overprepare and
> overthink things, but I'm usually pleased that I seldom forget
> anything or
> bring more than I need. I am, in short, ideally-suited to pack up a
> house,
> a family, and a business, and move them, my stuff, and myself 1,000
> miles
> while craftily leaving the hard work (loading the ginormous 26-foot
> Penske
> truck) to wife and family. Admire me, gentlemen. As you see, the way
> I do
> things, I leave plenty of time to wonder about The Big Things, like
> this
> dead horse.
I am so jealous of your organizational skills-On to Bend w/ the proper
air pressure!
grin,
Mr BZ-are you using nitrogen in your tires?
>
>
> --
> Mike "Rocket J Squirrel" Elliott
> 71 Type 2: the Wonderbus -- NOW SOLD TO THE BUYER OF OUR HOUSE
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
> KG6RCR
>
>
>
> On 8/8/2008 4:26 PM Tom Buese wrote:
>
>> Mr. Squirrel,
>>
>> I can't believe you have time to beat this issue to death when you
>> are leaving in 2 days? You must be completely packed & ready to go?
>>
>> LOL,
>>
>> Mr. BZ
>>
>>
>> On Aug 8, 2008, at 5:02 PM, Mike Elliott wrote:
>>
>>> Well. Yes. Of course. One /could/ use such a *sniff* low tech
>>> approach.
>>> One might as well plant a small boy back there with a video camera,
>>> Blair
>>> Witch-style, and review the tapes later.*
>>>
>>> There is something about your solution that I like: it appeals to
>>> my inner
>>> R. Goldberg. But my inner Mythbuster (read: Grant Imahara) wants
>>> accelerometers and graphs.
>>>
>>> I, personally, would combine your approach with my approach
>>> (subjective
>>> ball-watching v geeky graphs and stuff AND would add to it some
>>> means to
>>> inflate/deflate the tires remotely while in motion as well as sense
>>> and
>>> report back sidewall temperatures. I'm telling you: with sufficient
>>> funding this could quickly mushroom into a completely absurd
>>> project!
>>>
>>> ====================
>>>
>>> * Actually, if that wasn't so darn dangerous and illegal, it would
>>> be a
>>> great way to evaluate tire pressure v ride harshness!
>>>
>>> --
>>> Mike "Rocket J Squirrel" Elliott
>>> 71 Type 2: the Wonderbus -- NOW SOLD TO THE BUYER OF OUR HOUSE
>>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>>> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
>>> KG6RCR
>>>
>>>
>>>
>>> On 8/8/2008 9:41 AM Jim Akiba wrote:
>>>
>>>> For what you're trying to do, software, sensors and data are way
>>>> overboard I think. Match the solution to the problem... you simply
>>>> want to be able to verify that at X tire pressure you do or don't
>>>> have
>>>> an additional level of "bounciness" whatever that means correct?
>>>>
>>>> What not just grab a cheap video camera, some bungees, a plastic
>>>> wide
>>>> mouth jar big enough for a tennis ball, a ping pong ball, and a
>>>> softball for example(you might need something much heavier/lighter
>>>> depending on the displacement and frequency of bounce). Put the
>>>> tires
>>>> at X pressure, write that on a piece of paper and "show" this to
>>>> the
>>>> running camera(to link that tire pressure with the video with
>>>> certainty) that is now strapped to the trailer and recording the
>>>> ball
>>>> in the see through plastic container. Ride in a set path that you
>>>> will
>>>> repeat at whatever speeds you would like. Concentrate on road
>>>> safety
>>>> and consistency in driving. Change the tire pressure a few times
>>>> and
>>>> repeat. Simply watch the tape, and "see" what you can see... You
>>>> could likely run this test and have an idea of what you want in the
>>>> same amount of time it would take to track down a good sensor for
>>>> cheap, install the software, run the test, and analyze the data..
>>>> and
>>>> I'm almost 100% certain that interpreting the simple visual data
>>>> will
>>>> be much more intuitive for your average bear than raw numbers...
>>>> especially if you aren't sure of what range of displacements and
>>>> frequencies you're starting with(which you would really need to
>>>> ballpark to even pick the correct sensor)
>>>>
>>>> Hope this helps,
>>>>
>>>> Jim Akiba
>>>>
>>>> On Wed, Aug 6, 2008 at 12:06 AM, Mike Elliott
>>>> <camping.elliott@gmail.com> wrote:
>>>>> This is a question for the engineering geeks here.
>>>>>
>>>>> Say you were towing a little trailer behind your Vanagon. Say
>>>>> that the
>>>>> trailer had a rudimentary suspension consisting only of leaf
>>>>> springs. Say
>>>>> that this trailer also had tires, the pressure of which could be
>>>>> adjusted:
>>>>> higher pressure results in a harsher ride, while lower pressure
>>>>> results in
>>>>> a softer ride. Say you wanted to determine the optimum pressure
>>>>> of ride vs
>>>>> tire squishiness but were unable to find a small boy to ride in
>>>>> that
>>>>> trailer to report back about smoothness of ride v tire pressure
>>>>> while the
>>>>> experiments were being conducted, so lacking that small boy, your
>>>>> thoughts
>>>>> naturally turn to instrumentation. Okay, so say you had a laptop
>>>>> computer
>>>>> (WinXP) which could ride in the passenger seat, and /three/
>>>>> business days
>>>>> in which to acquire the needed sensor (accelerometer?) as well as
>>>>> the
>>>>> software to display the ride bounciness.
>>>>>
>>>>> Could it be done?
>>>>>
>>>>> --
>>>>> Mike "Rocket J Squirrel" Elliott
>>>>>
>>
>>
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