[Leica] It went to the moon!

Sat Feb 16 13:36:35 PST 2019

As a space geek, this has been a fascinating insight, Brian and Frank. 
Thanks for sharing.
Now that the interest in the Gravimeter has been cued, I wonder will 
anybody on the list bid for the one going for auction in a few days?

Douglas

On 16/02/2019 17:01, Frank Filippone via LUG wrote:
> Now this is just plain funny.....
>
> I worked at the MIT Draper Labs, as you suggest, after graduation from Tufts
> with a BSEE.  It was my first professional job, in the midst of terrible
> layoffs in the field.  I felt quite lucky to get a job, as the alternative
> was going to be grad school.
>
> The group I worked with, Skipper B, provided service mostly to do with
> testing gyros.  I remember a small heater cabinet the size of a refrigerator
> that contained gyros from Apollo, and Gemini missions.  They were prototypes
> and flight hardware.  In other jobs, I tested out the suspension system of
> the gyros,  We tested out at a remote ( Bedford Mass) lab that had a big
> spinning arm (200G's).  I do remember that we had an earlier test bed in
> Cambridge, in one of the MIT buildings, and we could measure the weight of
> trucks going by the building by the amount of force used to keep the gyro in
> a nominal position.  It was too noisy with traffic there, so the other lab
> is where the serious work was done.
>
> At the time, we got a contract to work on the Gravimeter.  Time's passage
> leaves me a bit sketchy on precisely what we did..... or specifically what I
> did, but I was to work under the direction of another group's chief
> scientist.  He was the one who had contact with the NASA folk.  I was too
> lowly to be involved in such stuff.   I was an analog design engineer by
> training.
>
> That chief scientist told me the story of the Gravimeter's failure, the
> negative comments by the astronauts, and the eventual failure of the
> apparatus.  He had met the Astronauts, and I remember being awed by such
> meetings, even though it was not myself doing the hand shakes.
>
> I also saw the Gravimeter at the Air and Space Museum.  Yes, I had the same
> pride as yourself in pointing out my one moment of fame, lowly though it
> was.  There is a special camaraderie in the team that made these instruments
> for NASA, that 50 years later, brings up strong memories.
> I stayed at MIT for about 2 years, at which time my financial situation
> needed to be altered for the better.... At which time I took a commercial
> job for $13,000, an improvement of $5,000.
>
> I remember my boss's name, but not the chief scientist... if you remember
> your contacts at MIT, I might remember which I worked for......
>
> Just too funny..... same project, almost 50 years ago.....
>
> Frank Filippone
>
> Red735i at verizon.net
>
>
> -----Original Message-----
>> From: LUG [mailto:lug-bounces+red735i=verizon.net at leica-users.org] On Behalf
> Of Brian Reid
> Sent: Saturday, February 16, 2019 7:55 AM
> To: Leica Users Group
> Subject: Re: [Leica] It went to the moon!
>
> This both a startling coincidence and some partly faded memories. While
> writing this, I think I figured out what is going on; I'll explain it at
> the end.
>
> I spent 5 years of my life (1968-1973) working on the planning and
> building of the Lunar Surface Gravimeter for Apollo 17, which was part
> of ALSEP (Apollo Lunar Surface Experiment Package). It was a research
> project of Dr. Joseph Weber of the University of Maryland, where I was
> employed. Dr Weber was trying to detect gravity waves, and he proposed
> to put one gravimeter on the moon and another on earth and look for
> events in which both instruments saw the same gravity disturbances.
>
> A gravimeter is basically a very sensitive scale with a fixed weight
> made of tungsten. If the scale shows a change in weight, and the thing
> you're weighing hasn't changed, then obviously gravity has changed. They
> were invented in the 1930s for oil exploration, and are still in use for
> that purpose.
>
> The actual gravimeter portion of the LSG was built by Lacoste and
> Romberg Inc of Austin Texas. It has since merged to form Micro G-Lacoste
> Inc: http://microglacoste.com/about/
> Here is a copy of the instruction manual for it that has been preserved
> by a university in Germany:
> http://userpage.fu-berlin.de/geodyn/instruments/Manual_Lacoste_GDl.pdf
>
> We added a lot of electronics to the Lacoste and Romberg device, so it
> could be used remotely. My role in the project was primarily software
> and telemetry, but in 1971 I needed to fill in for an engineer whose
> wife had just had their first baby, and I designed and drafted the masks
> for the 3-layer round circuit board that sat at the top of the unit to
> interface to the telemetry. When it came back from fab I installed it in
> a prototype and helped test it. It did a great job of transmitting data
> about the gravity on the 3rd floor of the Physics building at the
> University of Maryland. When it went off to Houston I never saw it
> again.
>
> The LSG was successfully taken to the moon and deployed by Eugene
> Cernan. There is a description here, with a photograph of it sitting on
> the surface of the moon:
> https://en.wikipedia.org/wiki/Apollo_Lunar_Surface_Experiments_Package#Apoll
> o_17
>
> Alas, it didn't work because the research engineers back at the
> University of Maryland (I'll name no names here) forgot to adjust the
> design to be calibrated for the moon's gravity and not the earth's
> gravity, and the dynamic range of the servomotor was not enough to
> compensate for this. I had participated in the calibration of the thing,
> which was done by driving it up and down a mountain near Roswell, New
> Mexico for about a week, taking measurements at each end of the trip.
> When a gravimeter is used in oil exploration, you don't care about
> absolute gravity values, you only care about changes. But when a cruise
> missile is flying, it cares a lot about the absolute strength of
> gravity, so the US Air Force got very involved in the calibration
> process for gravimeters used in survey work; they had originally
> calibrated the mountain (with pendulums) that we drove endlessly up and
> down.
>
> Recovered memory: there were actually two gravimeters onboard Apollo 17.
> The teams involved hated each other. Our LSG was part of ALSEP, the
> experiment package. The main mission also included the Traverse
> Gravimeter Experiment (TGE) which is described here:
> https://www.hq.nasa.gov/alsj/a17/a17-TGE.html. The TGE was built by
> Draper Labs, part of MIT. It rode on the back of the rover, which ALSEP
> devices did not. I'm guessing that your involvement was with the TGE and
> not the LSG. I know it wasn't LSG because I knew everybody on the LSG
> project well, and didn't know you. I had over the years forgotten about
> the second gravimeter onboard Apollo 17. Now it all comes back.
>
> NASA claims (https://www.hq.nasa.gov/alsj/a17/a17-TGE.html) that the TGE
> was used 26 times and "delivered excellent results". I don't know any
> un-official lore about it because I wasn't part of that group; in
> particular, I don't know anything about it being thrown off the rover.
> They were having serious problems with the rover because of a damaged
> fender.
>
> I took my family to Washington DC for a vacation in 1994 and I was
> stunned to see one of the backup LSG devices on display in the Air and
> Space Museum. I was thrilled to be able to point at it through the
> window and tell my children "I helped build that".
>
> I have no idea why I didn't take any pictures of it while I was working
> on it. I had my first Leica by then (a IIIf). Mostly I took pictures of
> people; I guess I didn't consider a lump of aluminum alloy to be
> photogenic.
>
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