Heard the News?

Big news from last week, and believe it or not, it had nothing to with Precision Scheduled Railroading, or the constitutionality of an impeachment trial when the impeached has retreated to the east coast of Florida.

Is such a thing even possible? Apparently so, because it was announced last week that several employees of BNSF received a patent in January 2021 for a “moving block system.” Turns out upon closer examination, the patented invention is not for a moving block system, but a fixed block system that is partitioned into a number of virtual track blocks within each fixed block. By detecting the presence or absence of “electrical circuit discontinuity” a virtual track occupancy or non-occupancy by a train can be derived for each of the virtual track blocks.

Full disclosure: I am not a signal engineer, an electrical engineer, a IT engineer, any sort of engineer, including locomotive engineer. My “expertise,” such that it is in the area of signaled train control, is derived from the patient explanations of principles and practices of safe train separation provided to me over many years by the extremely talented and dedicated designers, managers, and practitioners of signal based train control at Metro-North Railroad. I never miss an opportunity to express my gratitude to them all, from track level maintainers to department chiefs. I don’t have to mention names. They know who they are. However, I will mention one, Walter “Bud” Jackson, who passed away in 2017. He embodied the very best of the best practices in executing the installation of train control systems, and he never tired of trying to remedy my inexhaustible ignorance.

My ignorance remains inexhaustible, so any mistakes, errors of comprehension should not reflect on the efforts of those who tried to cure me.

What I do understand about train control systems, from the very beginning of such systems in the operating rules and timetables, through telegraphic delivery of train orders, through block signal systems manual and automatic, to microprocessor based systems, is that everything is based on a simple logic: everything is “if, then;” “yes” or “not-yes;” “no” or “not-no;” “on” or “not-on;” “off or “not off;” “1” or “0.” It’s a binary world, or world, at least at this non-molecular level, and you either are or are-not, and no fuzzy logic is allowed, much less necessary.

I’m not trying to offend anyone who bridles at the constraints of the binary world, but then, I usually don’t have to try. Just comes naturally to me.

Anyway, that logic is the way we have to do things to control the movement of trains; to prevent aberration from becoming chaos; to manage risk. The fact that I’m personally a confirmed binary might have something to do with my gravitation to, my affection for, my advocacy of the simple logic behind vital train operations but it does not diminish the validity of that logic.

The information pertaining to the patent grant can be found here.

I think I understand it. I’m not sure I understand how it works, but I believe I understand the claim for the way it is intended to work. Unfortunately, I just can’t call up my “mentors” from the C&S department and go over the document line-by-line, although if anyone, less ignorant than me, would like to do that, please email me at dmschanoes@ten90solutions.com and we’ll arrange a call.

Basic features of the proposed system as I understand, or fail to understand, them:

a) the physical block, defined by insulated joints at the outer opposing ends, is partitioned into virtual track blocks

b) an electrical circuit discontinuity is made detectable in one of the virtual track blocks created within the limits of the physical track block and

c) the discontinuity is used to generate a code indicating “virtual block occupied”

d) the code, indicating virtual block occupied or not occupied is transmitted to a train following within the limits of the physical block

The patent applicants detail description of their invention stating: [Note– to understand the description it is important to review them with the drawings accompanying the application]

a)Two methods of train detection are employed. One method determines rail integrity [broken-rail protection] in an unoccupied block. The other determines the train’s position in the occupied block along with broken-rail protection.

b) The description identifies as Track Code A (TC-A) the “available open source electrocode commonly used by railroads and is carried by signals transmitted via at least one of the rails of the corresponding physical block. ”

c) Track Code B (TC-B) is particular to this invention and “provides for the detection of train position within one or more virtual track blocks within an occupied physical track block and is preferably carried by signals transmitted by at least one of the rails of corresponding physical track block.”

d)”TC-A and TC-B may be carried by the same or different electrical signals….Generally, TC-A is dependent on a first location sending a coded message to a second location and vice-versa… On the other hand TC-B is implemented as a reflection of the transmitted energy using a transceiver pair with separate and discrete components. With TC-B, the system monitors for reflections of the energy through the axle of the train.”

e) A Virtual track block position message that represents occupancy data is determined by analysis of TC-A and TC-B signals and transmitted to computers onboard “locomotives in the vicinity.”

f) “TC-A is preferably implemented by transmitter-receiver pairs with the transmitter and receiver of each pair located at different locations. TC-B is preferably implemented with transmitter-receiver pairs, with the transmitter and receiver of each pair located at the same location. The signature of the energy from the transmitter is proportional to the distance from the insulated joint to the nearest axle of the train.”

So this is what I get from the patent material: within each physical block various “signal houses” or CILs are established. Each CIL generates and transmits electrical energy to discrete “packets” of track, with the packets corresponding to “virtual” mini-blocks. Apparently, even with a physical block occupied, the energy transmitted from the intermediate CILS to the rails degrades (or upgrades) with not only detectable differentiation, but also with some sort of uniform, repeatable differentiation dependent on the distance from the insulated joint to the nearest axle of the train. This principle of a “regular,” repeatable, decline or increase in the reflection of the energy dependent upon distance has to apply to both the “occupying” or entry-point insulating joint and “clearing” or departing insulating joint. If this is so, then indeed within the physical block, virtual blocks can be established at a distance equivalent to the signal design distance to zero mph from the end of a leading train.

So my questions are

a)Does that principle apply under all conditions? Do soil conditions, weather conditions, ballast conditions affect the reflection of the energy or the measure thereof?

b)Are deviations from that principle calculable, explainable by the mechanisms associated with the principle itself?

c)Does the principle apply to trains of any length, of any weight, operating at any speed?

d)What is the level of precision, and the rate of error associated with measuring this reflection of energy from the insulating joint nearest the lead or trailing axle of train?

The patent document states: “One technique for measuring track position and generating TC-B is based on currents transmitted from one end of a physical track black towards the other end of the physical track block and shunted by the wheel of the train. Generally (emphasis added), since the impedance of the track is known, the current transmitted from an insulated joint will be proportional to the position of the shunt along the block. Once the train position is known the occupancy of the individual track blocks is also known.”

Generally, “generally” is not adequate, nor sufficient for determining track occupancy, and let’s be clear, we’re not determining location for a performance measurement, we’re determining OCCUPANCY for an authority for movement. There is a big difference, with the latter being a vital determination requiring a vital process that complies with the “either, or” “yes, no” “on, off,” “go, no-go” logic of vital train operations.

If the vital requirement cannot be satisfied in either reliability, or accuracy, and by failure into the safe, no-go mode then the system cannot be used for train control.

Moreover, even if the detection system satisfies those requirements, there is another variable that compels investigation, and that variable is true braking rates. We have long been concerned when analyzing the safety of train control systems with “true ground speeds”– how the locomotive generates, and recognizes, its true ground speed. Since this is a locomotive-centric system for determining, and enforcing, allowable speed, a true braking rate must be known.

We do this by algorithm, but I’m not sure we have sampled enough real circumstances with real limitations on braking forces to radically reduce train separations.

We are always involved in turning a a variable quantity, required braking distance, into a vital quality, i.e sufficient braking is always available regardless of train make-up to prevent overruns of authorities. But we always have required, and executed, safe braking tests to validate the safe braking analysis that keeps our nightmares bad dreams and not our awake life. As we reduce train separations, reduce our “buffers,” the reality of different train braking rates becomes ever more vital.

Patent or no patent, please prove the invention satisfies the requirements of vitality, and prove it to someone like me, in my inexhaustible ignorance.

David Schanoes

February 15, 2021

What Happened

It seems the “host”— love the word, brings to mind images of men in tuxedos holding martini shakers, and it also brings to mind parasites– of my website decided to end support for a proprietary platform where Ten90 Solutions appeared. The alternatives offered were another proprietary platform and this, WordPress.

Thinking WordPress would be easier, simpler, and less of a hideous experience in general, I chose WordPress. Now it may be easier, simpler, but the experience is, for me, hideous in general.

Let me digress: I’m not worried that human beings working on artificial intelligence are going to produce machines that are smarter than me, or you, and certainly not smarter than my three grandchildren, ages 15, 9, and 5, all of whom are definitely smarter than me. I’m afraid that human beings designing artificial intelligence are, in doing so, going to make most other human beings using the artificial intelligence, more stupid.

The logic of the human experience won’t be reproduced in the machine as it is for example in railroad interlockings, but rather human intelligence will conform to and be constrained by the limits of the algorithms with which it engages daily.

Example? Did you hear the one about the locomotive engineer who blew by the stop signal but blamed his speed control system for not sounding the overspeed alarm when hit 18 mph on the restricting cab signal, when everyone knows you are not to exceed 15 mph while operating on a restricting? I am not making this up.

Is this a real fear? Are these the complaints of an old man feeling by-passed by and excluded from the marvelous changes taking place daily? Both?

I’m sticking with “both.” True story time. Once upon a March 2007 if I recall correctly, I attended a conference of the UK’s Adhesion Working Group in York, England. York, provincial capital of the Roman Empire, occupied by the Vikings in the 9th century when Ivar the Boneless (the Viking Version of the Spinners’ “Rubber Band Man”) attacked on All-Saints Day and caught the leaders of York praying. York, subdued, but not easily by the Normans in the 10th century and made an important railway center in the 19th century by George Hudson.

And in the 21st? There is a high-speed service (MAS about 200 km/hr) between York and London, where another meeting was scheduled. A colleague, then working at a firm spun off during the privatization of British Rail accompanied us and set us up for the high speed train departing 0800 hours, via LNER, arriving London Kings Cross at 1037 hours (I think).

The colleague had explained to me how advanced the UK system was, with its computer controlled dispatch that automatically made decisions regarding routing and what we used to call the superiority of trains, but is now known as “priority.”

“Including the terminals?” I asked

“Including the terminals,” he replied. “The dispatcher only intervenes if there’s a serious disruption or breakdown.”

I didn’t say anything. I didn’t like it. I’d been told for years that sooner rather than later computers would replace me. As a matter of fact, the person who first told me that was a consultant the VP-O had hired to plan the design and consolidation of the train control and traffic management functions of the entire railroad into a single location in Grand Central.

“Who’s going to be running the terminal?” I asked

“The computer will,” he replied

“And when we have to change track assignments, alter crew runs, and reschedule equipment turns, who’s going to do that?” I continued.

“You won’t be doing that anymore. That will be done upstairs in the control center, by the chief,” he said.

“Never happen,” I said.

“Why’s that?”

“No face to face. You have to tell crews, the mechanical department, everybody, directly, face to face what you want done. Otherwise it’s just another phone call to be ignored. Beside, dispatchers don’t want to deal with crew runs, passenger counts, equipment cycles, labor agreements, terminal configuration, boring stuff like that.”

“They’ll have to learn.”

He was from Britain, too. I was a Chicagoan transplanted to the East Village. We definitely didn’t speak the same language.

As luck or fate or just railroading would have it, our high-speed York to London express developed a pantograph problem shortly after departure, and the computer or the dispatcher, switched the train from the high speed “down” (or was it “up”) track to the low speed “down” (or was it up) track so the maintenance personnel could have easier access to the equipment and not tie-up, or tie-down, the high speed down, or up, track. I agreed with that. So far the computer and I were in perfect sync.

I looked at the timetable I had picked up in the station and saw that there was a second high speed train that was scheduled to depart York at 0825 hours, and I felt even better. With any lucky at all, the pantograph problem would get corrected, then the 0825 train could pick up our schedule, and we could assume its schedule and still get to London with time to spare. That’s how I’d do it, so naturally, I knew that would be how everyone, man, woman, or machine would do it.

Sure enough, the problem with the pantograph was corrected and, now 25 minutes late, we started to move south on the low speed down, or up track.

I figured we would stay on the low speed to the next interlocking where we would be lined behind the 0825 onto the high speed down, or up, and everything would be, as they say in England, ‘tickety boo,’ or ‘Bob’s your uncle,’ or some other expression just as wonderful. I was running through the list in my head of British slang, when the 0825 zipped by us at every bit of 200 km/hr.

Feeling ever so validated of my universal ability to determine the right course of action on any railroad anywhere and at anytime, I proudly told my British colleague what was going to happen and how we would run on the second train’s schedule. Bob’s your uncle indeed.

However, someone, somewhere, somehow, apparently wasn’t concerned with my knowledge of British slang, or how I thought the railroad should run, because our train did not cross over to the high speed down, or up, track at the next interlocking, or the interlocking after that, or the interlocking after that.

We were on the low speed down, or up, and there we stayed.

We were 47 minutes late by the time we were routed back to the high speed. I was, as you might have guessed, fuming. The high speed had remained clear, without another train to London passing us, just as the timetable said.

Finally, I looked at my British colleague/host, a soft-spoken man of unfailing courtesy, kindness, and ability, and said: “Graham, who’s decision is this to keep us on the down low, or low down or whatever, the computer’s or the dispatcher’s?”

“I don’t know,” Graham replied. “Why do you ask?”

“Because if the decision was the computer’s, when we get to London, I’m going to find it and unplug it.

“And if it was the dispatcher’s decision?”

“When we get to London, I’m going to find him, or her, and I’m going to fire him.”

So here we are, on a platform that’s supposed to be almost intuitive– so easy a child could do it. And here I am, without a clue; frustrated more than any child; having to figure out how to move and archive all the other postings on the other platform to this one.

Piece of cake, easy as pie, absolutely scrummy.

David Schanoes

January 19, 2021