Hi Randall=0AIn your discussion of the cosine shaped strips, my mental pict=
ure got really fuzzy at the end. If I have 4 strips and I weld pairs togeth=
er I now have=C2=A0 2 units. I have trouble visualizing the 2 units arrange=
d so they have 4 fold symmetry. I missed something..=0APete=0A=0A=0A=0A____=
____________________________=0AFrom: Randall Peters =
=0ATo: "'psnlist@..............." =0ASent: Tuesday,=
 August 16, 2011 8:35 AM=0ASubject: material choices and/or configuration c=
hanges=0A=0A=0AI read with much interest several of your recent comments co=
ncerning materials other than the conventional (standard alloy) metal for u=
se in the spring of a vertical.=C2=A0 The comment about nano tubes caused m=
e to think about how I will never forget the lecture given at TTU years ago=
 by the discoverer of the =E2=80=98bucky ball=E2=80=99 (Richard Smalley, Ri=
ce University Chemist).=C2=A0 Several of us made bets on how long it would =
take for him to receive the Nobel Prize for this work.=C2=A0 =C2=A0He =E2=
=80=98punctuated=E2=80=99 the serendipitous nature of his discovery by ment=
ioning =E2=80=9Chow he expected there would have been a =E2=80=98telephone =
ringing from heaven=E2=80=99 had he not finally realized what =E2=80=98lay =
before him in plain sight=E2=80=99. =0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0How I =
wish that I had some samples on hand to do experiments with various exotic =
materials involving nanotubes, since my guess is that they just =E2=80=9Cmi=
ght be the ticket=E2=80=99 to solving a lot of our problems.=C2=A0 =C2=A0In=
 the meantime, I would like to propose that somebody take the lead to look =
at possible (significantly different) other ways to maybe improve what we=
=E2=80=99ve presently got to live with.=C2=A0 Would it be smart, for exampl=
e, to try and use torsional restoration as opposed to the conventional coil=
ed spring.=C2=A0 Yes, Lucien LacCoste changed the history of seismology (as=
 a tennis player, while solving a problem given to him by his physics profe=
ssor Romberg, while at UT Austin).=C2=A0 He =E2=80=98pulled a coil inside o=
ut=E2=80=99 to generate a zero-length configuration that is much less susce=
ptible to creep than previous springs.=C2=A0 I have often wondered if any o=
f the gravimeters he built may have also used fuzed silica (quartz), since =
it is a much more stable material
 than most other types (unfortunately brittle and nonconductive).=0AThen Er=
hard came along and invented (patented) the astatic spring to give similar =
performance.=C2=A0 So there may be several ways to =E2=80=98skin a meso-ane=
lastic cat=E2=80=99.=C2=A0 =C2=A0=0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0One of my ideas that was shown as a prototype at the broadband con=
ference I would like for some of you to think about.=C2=A0 You can find a p=
icture of my =E2=80=9Ccompound vertical seismometer=E2=80=9D on the IRIS li=
nk by simply typing the keywords into Google.=C2=A0=C2=A0 And if you want t=
o better understand the physics of how it works (benefit of period lengthen=
ing being possible by using the =E2=80=98beauty=E2=80=99 of the eccentric i=
n latest generation bows), you might want to read the other paper that foll=
ows, titled =E2=80=9CArcher=E2=80=99s compound bow, smart use of nonlineari=
ty=E2=80=9D. =0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0When I showed thi=
s prototype to some of those in attendance at the broadband conference=E2=
=80=94several of them were positively impressed.=C2=A0 They seemed to think=
 of it more as a toy, however, than being practical; but I believe Erhard w=
as in earnest when he mentioned that I should try to get the amateur seismo=
logy community interested in doing some experiments with it.=0A=C2=A0=C2=A0=
=C2=A0=C2=A0 Be apprised that it is susceptible to creep, as shown in my pa=
per, titled =E2=80=9Ccreep enhanced sensitivity of seismometers=E2=80=9D, o=
nline at=0Ahttp://arxiv.org/abs/physics/0508105=0A=C2=A0=C2=A0=C2=A0=C2=A0 =
The approach using torsional restoration could be closer , in fact, to that=
 of operating with a coil than you might think.=C2=A0 Few people in my expe=
rience realize that the spring constant of a coil depends on the shear modu=
lus.=C2=A0=C2=A0 In other words, it is the twisting of the wire of the coil=
 that is key=C2=A0 One of the truly impressive physics demonstrations, that=
 shows that the coil actually wants (unless constrained otherwise) to wind =
and unwind under load change=E2=80=94is the Wilberforce pendulum which exhi=
bits mesmerizing mode coupling behavior. =0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0A=
nd for those of you who want to retain the remarkable properties of force b=
alance, there is no reason why you can=E2=80=99t use it with this compound =
vertical instrument. =0AAlso, mention was made of the possible use of singl=
e crystal silicon.=C2=A0 I have used reject (previous generation 3-in) wafe=
rs to great advantage in some of my experimental efforts.=C2=A0 It is very =
easy to diamond scribe and cleave them into rectangular shapes.=C2=A0 They =
are more elastic than one might tend to believe, and it may be possible to =
make some useful springs out of them.=C2=A0 They should be much better than=
 any metals that I know about, because a given atom is far more prone to st=
ay where it is supposed to.=0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 Finally, I wou=
ld like to mention some work, involving springs, by the gentleman who chang=
ed the world of earth field measurements.=C2=A0 =C2=A0Jim E. Faller pioneer=
ed the free-fall method of measuring g, by counting fringes as a cube-corne=
r reflector falls in a vacuum (within a vacuum) to eliminate air drag.=C2=
=A0 Using a laser interferometric setup to generate the fringes, he improve=
d the accuracy of the g-measurement by several orders of magnitude.=C2=A0 =
=0A=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0When Jim gave a seminar years ago at TTU, =
he also mentioned to me some ideas about springs that he had.=C2=A0 Don=E2=
=80=99t know whether he ever refined and published his thoughts along the f=
ollowing lines.=0A=C2=A0=C2=A0=C2=A0 Take four strips of elastic rectangula=
r pieces, several times longer than wide.=C2=A0 Form a single-cycle cosine =
wave permanent (unstrained) shape in each of the strips.=C2=A0 Take two of =
the thus formed strips and =E2=80=98weld=E2=80=99 their ends together to fo=
rm a shape similar to the leaf spring of an old truck.=C2=A0 Do the same wi=
th the other pair, and then assemble the four into a single structure havin=
g 4-fold rotational symmetry.=C2=A0 Thus it has a stand-alone (stable arran=
gement) capability to support a load that would be placed on its top.=C2=A0=
=C2=A0 Has anybody tried something like this?=C2=A0 It should be possible t=
o gang several of them together to increase the operational length and decr=
ease the net spring constant (like springs in series).=0A=C2=A0=0A=C2=A0=C2=
Hi Randall=
In your discussion of the cosine shaped strips, my =
mental picture got really fuzzy at the end. If I have 4 strips and I weld p=
airs together I now have  2 units. I have trouble visualizing the 2 un=
its arranged so they have 4 fold symmetry. I missed something..
Pete

From: Randall Peters <PETERS_RD@..........>
To: "'psnlist@..............." &l=
t;psnlist@..............>
Sent:=

 Tuesday, August 16, 2011 8:35 AM
=
Subject: material choices and/or configuration changes

I read with much interest several of your recent comments concerning mate=
rials other than the conventional (standard alloy) metal for use in the spr=
ing of a vertical.  The comment about nano tubes caused me to think ab=
out how I will never forget the lecture given at TTU years ago by the disco=
verer of the =E2=80=98bucky ball=E2=80=99 (Richard Smalley, Rice University=
 Chemist).  Several of us made bets on how long it would take for him =
to receive the Nobel Prize for this work.   He =E2=80=98punctuate=
d=E2=80=99 the serendipitous nature of his discovery by mentioning =E2=80=
=9Chow he expected there would have been a =E2=80=98telephone ringing from =
heaven=E2=80=99 had he not finally realized what =E2=80=98lay before him in=
 plain sight=E2=80=99. 
 &n=
bsp;   How I wish that I had some samples on hand to do expe=
riments with various exotic materials
 involving nanotubes, since my guess is that they just =E2=80=9Cmight be th=
e ticket=E2=80=99 to solving a lot of our problems.   In the mean=
time, I would like to propose that somebody take the lead to look at possib=
le (significantly different) other ways to maybe improve what we=E2=80=99ve=
 presently got to live with.  Would it be smart, for example, to try a=
nd use torsional restoration as opposed to the conventional coiled spring.&=
nbsp; Yes, Lucien LacCoste changed the history of seismology (as a tennis p=
layer, while solving a problem given to him by his physics professor Romber=
g, while at UT Austin).  He =E2=80=98pulled a coil inside out=E2=80=99=
 to generate a zero-length configuration that is much less susceptible to c=
reep than previous springs.  I have often wondered if any of the gravi=
meters he built may have also used fuzed silica (quartz), since it is a muc=
h more stable material than most other types (unfortunately brittle and non=
conductive).
Then Erhard came along and invented (pate=
nted) the astatic spring to give similar performance.  So there may be=
 several ways to =E2=80=98skin a meso-anelastic cat=E2=80=99.   <=
/div>
     &n=
bsp;  One of my ideas that was shown as a prototype at the broadb=
and conference I would like for some of you to think about.  You can f=
ind a picture of my =E2=80=9Ccompound vertical seismometer=E2=80=9D on the =
IRIS link by simply typing the keywords into Google.   And if you=
 want to better understand the physics of how it works (benefit of period l=
engthening being possible by using the =E2=80=98beauty=E2=80=99 of the ecce=
ntric in latest generation bows), you might want to read the other paper th=
at follows, titled =E2=80=9CArcher=E2=80=99s compound bow, smart use of non=
linearity=E2=80=9D. 
  =
;     When I showed this
 prototype to some of those in attendance at the broadband conference=E2=80=
=94several of them were positively impressed.  They seemed to think of=
 it more as a toy, however, than being practical; but I believe Erhard was =
in earnest when he mentioned that I should try to get the amateur seismolog=
y community interested in doing some experiments with it.
     Be apprised that it is=
 susceptible to creep, as shown in my paper, titled =E2=80=9Ccreep enhanced=
 sensitivity of seismometers=E2=80=9D, online at
http://arxiv.org/abs/physics/0508105
     The approach us=
ing torsional restoration could be closer , in fact, to that of operating w=
ith a coil than you might think.  Few people in my experience realize =
that the spring constant
 of a coil depends on the shear modulus.   In other words, it is =
the twisting of the wire of the coil that is key  One of the truly imp=
ressive physics demonstrations, that shows that the coil actually wants (un=
less constrained otherwise) to wind and unwind under load change=E2=80=94is=
 the Wilberforce pendulum which exhibits mesmerizing mode coupling behavior=
.. 
     =
;And for those of you who want to retain the remarkable properties of force=
 balance, there is no reason why you can=E2=80=99t use it with this compoun=
d vertical instrument. 
Also, me=
ntion was made of the possible use of single crystal silicon.  I have =
used reject (previous generation 3-in) wafers to great advantage in some of=
 my experimental efforts.  It is very easy to diamond scribe and cleav=
e them into rectangular shapes.  They are more elastic than one might =
tend to
 believe, and it may be possible to make some useful springs out of them.&n=
bsp; They should be much better than any metals that I know about, because =
a given atom is far more prone to stay where it is supposed to.
      Finally, I w=
ould like to mention some work, involving springs, by the gentleman who cha=
nged the world of earth field measurements.   Jim E. Faller pione=
ered the free-fall method of measuring g, by counting fringes as a cube-cor=
ner reflector falls in a vacuum (within a vacuum) to eliminate air drag.&nb=
sp; Using a laser interferometric setup to generate the fringes, he improve=
d the accuracy of the g-measurement by several orders of magnitude.  <=
/div>
     Wh=
en Jim gave a seminar years ago at TTU, he also mentioned to me some ideas =
about springs that he had.  Don=E2=80=99t know whether he ever refined
 and published his thoughts along the following lines.
    Take four strips of elastic recta=
ngular pieces, several times longer than wide.  Form a single-cycle co=
sine wave permanent (unstrained) shape in each of the strips.  Take tw=
o of the thus formed strips and =E2=80=98weld=E2=80=99 their ends together =
to form a shape similar to the leaf spring of an old truck.  Do the sa=
me with the other pair, and then assemble the four into a single structure =
having 4-fold rotational symmetry.  Thus it has a stand-alone (stable =
arrangement) capability to support a load that would be placed on its top.&=
nbsp;  Has anybody tried something like this?  It should be possi=
ble to gang several of them together to increase the operational length and=
 decrease the net spring constant (like springs in series).
  
      Randall

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