Archive for the ‘FRIENDS’ Category

WHAT AM I TO DO ABOUT CHRISTMAS?


I do not know what I am going to about Christmas Day or even the few days remaining leading up to the holiday. I had hoped that my experience with Thanksgiving would have provided me with some clues but no luck there. I opted out of going to North Las Vegas to see my son Dan because I got a massive case of cold feet about leaving my comfort zone and not having good ways to mitigate the effects of the difficulties of my daily existence. My son John and his wife drove in from Lancaster and spent thanksgiving day with us and we had a good visit and a quiet meal. I cried some after the meal when I began thinking of the family members who have passed away. I know well that the lot of the survivor is to bear the grief one feels when someone you love passes away. This grief accumulates as one gets older and more people die. The temptation to suppress memories becomes greater and that is one of my greatest concerns – that time will dim my memories of Patty. The holiday season is particularly hard as it seems like every thing that touches my life does remind me of Patty and our life together. I sometimes mentally flog myself for being too sorry for myself when the memories become too vivid. I try to not pursue that train of thought because it does me no good. My son David, I know, is feeling the holiday effect. He is doing a lot of work in our yard,  front and back, to put the place into good shape for his Mom. She would be very proud of the place.

I frequently have to remind myself that Patty was a mother, sister, grandmother, great grandmother, great great grandmother, aunt, in – law, and friend to many as well as my wife for 66 years. I feel at times that I have fallen short in my duty to properly commensurate with the many persons who have been hurt by Patty’s death. This, I fear, is the result of me being me – for better or worse. My only defense is that speaking and thinking about Patty is painful for me and I cry a lot –  neither of which is among my favorites. 

I am slowly becoming more tolerant of the mental anguish that seems to afflict me when I dwell on my life with Patty. I am trying to stay connected with family and friends and I am writing this Post to my Blog as part of my effort stay engaged. It seems to help me a lot. I recently published a gallery made up of images of Patty that I ran across as I went through my image files. I made up my mind that I had to confront my difficulty in viewing these images. This has done me some good, I think, because I am thinking of getting out the  slide images I took on our Alaska adventures and using them to illustrate a post, yet to be to be written, about those very happy times in our life. Bear with with me my friends, I will be OK.

As to my plans for the next few days – I still don’t Know. I’ll just take it day by day as I have been.

 

 

TODAY WAS A VERY GOOD DAY


A few days ago, I received an E-mail message from the science teacher with whom I had worked as a classroom volunteer a couple of years ago. We had known each other for a long while and he was asking how I was doing. We had not communicated with each other for nearly two years. One message  led to another and we ended up making a plan for us to visit the Orange Empire Railroad Museum (OREM) today. He picked me up at my house this morning and we had an uneventful trip to the museum. Once there, I got some minor photography chores out of the way and we moved on to the main business of the day which was to show Myles the museum. He visited the museum ten years ago and much had been done to improve the museum since that visit. We started by touring “Grizzly flats” where the 3′ gauge equipment is on display. He was interested in seeing how the work to rebuild the “Emma Nevada” locomotive was being carried out. We walked out of the the building and looked at the narrow gauge “armstrong” turntable and the partially completed water tank. I told him the history of the Ward Kimball gift to the museum and what the gift enabled the museum to accomplish. I also told him we need $30,000 to buy the redwood staves needed to finish the tank. You never know. However, he demurred! We then drove over to the shop area “outback”, where the BIG locomotives are being rebuilt.  Myles was blown away by the size of the locomotives in the shop and the complexity of the work being done by the volunteer mechanics. He was particularly impressed by the 108’s paint job. He thought it very well done. A very old (1939) EMC diesel switching locomotive was being worked on and a crew was installing one of two truck assemblies to the locomotive. Earlier they had discovered that one of the two newly rebuilt truck assemblies did not roll  properly. They subsequently discovered an axle bearing that was worn such that the lubrication oil was being wiped off the bearing as it rolled and this removal resulted in the observed high friction. I was very pleased to learn they had used the Pratt & Whitney jig bore machine to rebore the bad bearings. This machine does not get much attention as it looks old and tired. This machine has the capability to bore a 12′ deep hole and we keep the ancient machine around because of this capability. It was by then lunch time and I had no trouble convincing Myles that we should drive into Perris for lunch. I took him to Jenny’s Restaurant and there we had a tasty lunch consisting of a bowl of chili for me and a chili size for Myles. During lunch I elaborated on the stories I had told him earlier about the 55 year history of the museum. The drive home was at times slow but it was uneventful – always a blessing. 

I am very appreciative of the time Myles spent with me on our excursion to OERM and I want to thank him for making the trip. I hope to do it again.

 

 

 

MORE ON THE AUTONETICS G5B GYRO


Yesterday I went to lunch with my fellow Autonetics retirees, at least those who are left. I sat next to a fellow retiree, an old friend of mine. We spoke briefly of his experiences when he was working on the design of the test equipment used in the production of the “Houndog” missile’s G5B gyros. He also told me that the work done in the development of the G5B was done using Navy money. This leads me to speculate the Navy may have had need for the N5 IMU. At about this time the Navy was procuring carrier based bombers from NAA. I wonder if there was any connection?  This information may explain the Navy depot stamp seen in the photo. He told me of the G5B gyro float balance weight adjustment procedure and described to how it was done. The gyro was operated in four different positions with respect to the gravity vector and at each of these positions, the rotor was spun in both the positive and negative sense. At each position, the magnitude of the torquer current necessary to precess the rotor while keeping the pickoff nulled was recorded. The change in float balance weights necessary to bring the float into balance was calculated from the eight values of torquer current recorded. He remembered the hectic pace of the production work for the G5B gyro and the pressure he felt whenever the production 0f the gyros slowed down. I know well what he means.

He told me the pump power frequency was 10 Hz. He doubted the float was subjected to any further machining after final assembly.

It was good to see my fellow Autonetics retires again. We made plans to meet again next year.

A TAPE RECORDER AND BORED TECHNICIANS


It will be no surprise to anyone that night workers in the Instrument lab sometimes became bored. Monitoring the drift test of SINS gyro is not like doing aerobic exercises; its more like trying to outrun a sloth. The technician assigned to monitor a drift test was required to periodically measure the magnitude of the current flowing through the torquer coils of the test gyro. As part of the ritual performed during the startup of a drift test, this current was caused to flow thru the test gyro’s torquer coils such that the gyro was observed to be stationary with respect to the room. The technician was trying to determine the torque that would be necessary to keep the gyro precession rate as close as possible to the rate at which the room was turning. The accumulated angular difference that resulted from the inevitable small difference in the two rates was recorded using a Bristol strip chart recorder.  It was important that the torquer current magnitude be measured periodically to provide proof it did not vary during the drift test. The current magnitude was measured using equipment that today would be considered as museum pieces. They consisted of a large potentiometer, a galvanometer, a bridge circuit using high precision resistors, and a dust cloth. The dust cloth was necessary to enable the technician to keep the shiny black surfaces of the galvanometer clean. (Dr. Pickrell, the Vice President and General Manager of the Marine System Division, had a habit of writing his initials in the dust and there was hell to pay if they were still there the next time he came by.) The measured value was was entered into a logbook. This left plenty of time for other “projects”.

I had just transferred into the lab from the machine shop. I remember one night being asked if I knew about the tape recorder test. I indicated that I did not. I was taken to an old reel to reel tape recorder that had a set of ancient earphones attached and a microphone. I put on the earphones as I was asked to do. I was handed something to read out loud and the tape recorder was started. I started to read out loud using the microphone and almost instantly found I could not continue. I tried several more times with the same result. During the ensuing discussion with the onlookers, I was informed that they had found nobody who was able to read out loud. I examined the setup and discovered, with the help of the onlookers, that the tape recorder was rigged so that a small time delay was introduced between the microphone input and the output to the earphones. I have never been informed of the reason for this apparent disabling of the brain circuits by this time delay. I still wonder what happened to my brain.

POLHODE – A NEW WORD


If an ESG ball were made without the Tantalum inclusions and such a ball was spun up to the normal rotor speed and the ball was maintained at the normal operating temperature, the spinning ball would be round and homogeneous. It would show no evidence of a MUM signal as the surface of the rotating ball would be running “true”.( To use a word taken from the machinist’s lexicon.) The ball would be symmetric around any axis of the ball; the moments of inertia, measured around any axis of the spinning ball ball, would be the same. It would be a very uninteresting spinning ball. If, on the other hand, the Tantalum inclusions were magically inserted into the spinning ball such that the ball spins around what is now the axis of the greatest of the ball’s moments of inertia, and the other conditions under which it is spinning were the same, the surface of the spinning ball would be found to be”running out” by 40 microinches (if my memory is correct) when measured in the plane normal to the spin axis of the ball. If an observer had the patience to monitor the spinning ball for a long time, he, or she, would find the ball appeared to not move relative to an inertial frame of reference. In particular, the “run out” of the surface of the ball would remain at 40 microinches. The observer would be justified in concluding the spinning ball’s position in inertial space is stable, ie, not changing with time. Now spin the ball down until it has stopped spinning. Go to lunch and relax.

After lunch, spin the ball up to the normal speed and bring the temperature of the ball up to the normal temperature. As before, measure the runout of the ball’s surface in the plane normal to the spin axis of the ball. To the great consternation of the observer, the”run out” is less than 40 microinches and, worse, it is slowly changing with time. As time goes on, the observer finds that the runout is slowly increasing and after more time realizes the “runout” has moved up to 40 microinches and is no longer changing. Just to be  sure, the observer waits for more time to pass and, finally, concludes the ball is back to normal, ie, spinning as before the spin down of the ball.

The observer concludes that a pretty fair gyroscope can be made using the asymmetric spinning ball, if some way can be found to shorten up the time it takes the ball to come a stable equilibrium condition. The time to reach this equilibrium “naturally” is not acceptable for any practical navigation system. After some time spent reviewing the relevant theories of the rotation of asymmetric balls, the observer concludes that the observed behavior of the spinning ball can be attributed to these factors:

1.) The asymmetric ball described above has three moments of inertia, each greater in magnitude than the one before it. The three moments of inertia of lie on mutually orthogonal axes. (inertia means “resistance to change”)

2.) The ball, when spinning such that the spin axis lies along the axis of the maximum moment of inertia, is in a stable spin state that will not change over time.

3.) The ball, when spun up to the normal speed, will not, in general, be spinning such that the spin axis lies along the axis of the greatest moment of inertia. It is spinning in an unstable state. Over time the position of the ball will drift toward the stable condition described in 2.).

4.) The path, or motion, of the ball above is called the polhode.

What is needed is an “artificial” scheme to cause the drift of the ball toward the stable position to happen in a much shorter time. This in effect requires that information within the ball “run out” signal must be decoded to determine the magnitude of the difference between where the ball is now and where the ball should be when it is stable, ie, where are we relative to where we want to go. To achieve this, a solid theoretical understanding of the polhodes must be gained and the means by which to move to ball with respect to the spin axis, without moving the spin axis in inertial space, must be developed. The scheme must differentiate between the two possible final orientations of the spin axis with respect to the axis of maximum moment of inertia to enable the control of the polarity of the mass unbalance along the spin axis.

I hope the reader of this has gained a feeling for the process known as “polhode damping”. The process is required to be performed each and every time an ESG rotor is spun up prior to use as a gyroscope. The time allowed to perform polhode damping ranges from “take all the time you need” for test equipment to the astounding 45 second requirement of the N73 system. (the N73 average time was 22 seconds.). I had to learn how to perform polhode damping on test ESGs by what is called “the manual method”. It required the use of old fashioned knobs to control the motor voltage and the recognition of the polhode you were moving on using MUM signals displayed on Bristol Chart Recorders. I was hopelessly lost in the beginning, but with the patient help of Gerry Hardesty, I finally developed a knack for the process.

The development of the N73 polhode damping software was done by Dr. John Wauer. I was very impressed with the software. John was never able to find simple enough explanations of how the software did its thing in such a way as to bring me to a high level of understanding. To this day I still wonder how the motor used for rotor spinup was used to move the rotor without any effect on the rotor spin axis. It must be magic!

I do not recall much discussion on the part of laboratory people about polhode damping and I attribute that to the complex nature of the process. It was not possible to concoct short and sweet answers to questions about polhode damping. As a group, the engineers and technicians of the test laboratories were very proficient in carrying out their assigned tasks and I was, and still am, proud to be counted with them. The labs I worked in all have been leveled but we all have lasting memories of the work we did – at least those of us that are still alive still have memories of those times – when “cost plus” reigned.

 

 

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