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Oil Train

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Posted by Euclid on Monday, April 6, 2015 12:45 PM
Overall, I see this approach to reducing tank car breaches by directly controlling or avoiding derailments.  There are four steps, with each step progressively adding more protection.

1)    ECP brakes to shorten the train stopping distance due to their instant application.

 

2)    Empty/Load sensors to further shorten train stopping distance by allow a higher brake force on loads.

 

3)    Derailment sensors to further shorten train stopping distance by applying brakes when a derailment occurs instead of waiting until the train parts; and to prevent derailments from becoming pileups.

 

4)    Differential braking to further prevent derailments from becoming pileups.

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Posted by zugmann on Monday, April 6, 2015 12:09 PM

Also misleading.  While the prinicples of the air brake are the same, it isn't the same beast.  Control valves have been improved upon (quick release and apply features).

It's been fun.  But it isn't much fun anymore.   Signing off for now. 


  

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Posted by jeffhergert on Monday, April 6, 2015 11:48 AM

zugmann
 
Euclid
One example would be replacing 150 year-old compressed air braking technology with electronically controlled pneumatic braking on the new tank cars now coming online.

 

 

I love that.  Notice how the author replaced air with pneumatic to make it sound all hi-techy! 

People fall for that crap, I guess.

 

To be fair, they just spelled out ECP instead of using the initials.  At least at first.  Probably so the uninitiated would know what ECP stands for.

Jeff

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Posted by BaltACD on Monday, April 6, 2015 11:30 AM

zugmann
Euclid
One example would be replacing 150 year-old compressed air braking technology with electronically controlled pneumatic braking on the new tank cars now coming online.

 

 

I love that.  Notice how the author replaced air with pneumatic to make it sound all hi-techy! 

People fall for that crap, I guess.

 

Yep - 150 year old pneumatic braking to be replaced with compressed air and electricity - how Edisonian!  Where is Nichola Tesla?  Still with George Westinghouse?

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Posted by zugmann on Monday, April 6, 2015 10:56 AM

Euclid
One example would be replacing 150 year-old compressed air braking technology with electronically controlled pneumatic braking on the new tank cars now coming online.

 

I love that.  Notice how the author replaced air with pneumatic to make it sound all hi-techy! 

People fall for that crap, I guess.

It's been fun.  But it isn't much fun anymore.   Signing off for now. 


  

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Posted by Euclid on Monday, April 6, 2015 9:43 AM
Here is international consulting group, Oliver Wyman echoing my ideas.  Note that they have not yet gotten to my idea of differential braking as the ultimate safety enhancement. 
Quotes from Oliver Wyman, see pages 5-6:
“With so many new cars being introduced onto the rail network, and given that most crude oil is being targeted for unit train operations, this may raise opportunities for step changes in fleet safety and performance. One example would be replacing 150 year-old compressed air braking technology with electronically controlled pneumatic braking on the new tank cars now coming online. This would enable braking to be applied faster and more consistently in a unit train in the event of an incident…”
 
“With electronic train lines from ECP braking systems, it might also make sense to equip the trucks on tank cars with sensors that could detect the kind of rough sudden motion that indicates a derailed wheel set and immediately apply the brakes on the train. Seconds count in a derailment event, and this would stop a train far more quickly than waiting for the derailment to progress to the point that the train line was severed…”
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Posted by Norm48327 on Monday, April 6, 2015 8:50 AM

The broken record keeps playing the same song over and over and over. Bang Head Bang Head

Norm


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Posted by Euclid on Monday, April 6, 2015 8:02 AM
I do not see any insurmountable obstacles to applying derailment sensors to oil trains.  As Paul North has shown, derailment sensors are in widespread use in other countries.  Those are mechanical sensors which could be applied to our oil trains with their existing brakes.  But what I advocate is converting to ECP brakes, and then applying electronic derailment sensors powered through the ECP wire and sending communications to stop the train through that same wire.
One problem with the mechanical sensors and conventional brakes is that the response to detecting a derailment is dynamiting the train.  Furthering that problem is the fact that the emergency application will begin at the point of the derailment and propagate in two opposing directions. 
Getting a derailed train stopped before it commences jackknifing is a delicate proposition.  So, while an emergency brake application gets the train stopped as quickly as possible, it also has the potential to excite the delicate situation of a derailed, dragging car in a way that induces it to jackknife and start a pileup.
With a sensor system based on ECP brakes, there is the option of reacting to a derailment with a brake application other than an emergency application propagating in two directions from the point of derailment.  
For instance, the ECP brake application, upon detecting a derailment, does not propagate directionally at all.  It is uniform and instantaneous.  It also does not have to be full braking force coming on all at once like an emergency application of conventional air brakes.  The ECP brake application upon sensing a derailment can also be a programmed, modulated response designed for the delicate task of getting the train stopped before the dragging car causes a pileup.
Or to put this another way, the mechanical derailment sensors, upon detecting a derailment, could actually trigger a pileup that would not have happened without derailment sensors.      
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Posted by blue streak 1 on Monday, April 6, 2015 3:03 AM

Slightly off topic is a question.  Is any of the oil train product and / or pipeline going back into the strategic oil reserve ?  Wasn't there a withdrawl several years ago ?  Seems like a good time to " fill er up ".  Naturally any Bakken or other product volitility would need to be delt with.

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Posted by Paul_D_North_Jr on Sunday, April 5, 2015 9:19 PM

I'm not sure of the 'country of origin' of the derailment detector, but it's in use on more than just the Swiss railways.  From slide 10 of 18 at:

http://www.otif.org/fileadmin/user_upload/otif_verlinkte_files/05_gef_guet/03_AG-Entgleisungsdetektion/2014_10/CE_GTDD_2014-A_Annex_V_Presentation_Knorr-Bremse_E.pdf   

Switzerland - 1,800+/- of the "EDT100" model, 713 of the "EDT101" model

France 114 

Germany 720

Slovenia 161

Slides 15 and 16 have 2 case studies where these detectors operated during slow-speed derailments.

- Paul North. 

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by Euclid on Sunday, April 5, 2015 11:47 AM
Paul,
Thanks for posting that reference to the Swiss derailment detector.  It is interesting to note that their device is all pneumatic for application to cars with conventional air brakes.
They make the same point that I have been making here to the skeptics.  That is that every derailment does not instantly lead to a chaotic pileup as has been suggested by the reference to the Tornado derailment on the U.P. posted earlier.  The Swiss report says this:
“A derailment does normally not lead to an immediate as the car continues to run until an “obstacle” like a switch comes in the way.”
 
As the two above videos show, in some derailments, cars can be dragged in line for long distances without ever progressing to chaotic jackknifing.  And this is not dependent on relatively slow speed typical of the two videos.  I have seen a case where a car was dragged 4 ½ miles at about 50 mph, breaking every tie, creasing every tie plate, mashing spikes, and continuously throwing ballast 20 feet from the track.  It was a burned off journal, and the car stayed in line all the way. 
Another identical incident occurred at the same location, but the car finally hit a crossing diamond, and tipped over, thus parting the train.  I have seen other similar dragging instances.
But the point is that these incidents could have led to a massive, destructive pileup with all the destruction and possible death or injury that is implied.  A derailment sensor would have had plenty of time to prevent that outcome. 
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Posted by BaltACD on Sunday, April 5, 2015 11:26 AM

Paul_D_North_Jr

As a result of that and some other high-profile derailments, there was an attempt by the Navy Ordnance people to develop several kinds of sensors to detect derailments, "hot boxes", and other mishaps before they got too far out of control and caused other bomb shipments to explode; all of this was reported in Trains or Railway Age at the time.  I specifically recall that the hot box detector would be mounted in or on the truck frame.  Whether any of this was ever fielded for tests and then made practical (even if not widely adopted), I do not know.

- Paul North.  

 

I believe Amtrak uses on board Hot Box detection equipment.  At least on my carrier, if a Amtrak car activates 2 Hot Box Detectors, the Amtrak car can continue in the train if the On Board Detector indicates no defect.  With freight cars rule require a car activating 2 HBD's to be set out, PERIOD, even if the journal shows as being of 'normal' temperature.

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Posted by Paul_D_North_Jr on Sunday, April 5, 2015 11:00 AM

At least one company has developed a derailment detector - in response to 3 tank car derailments in Switzerland ! (in the 1990's)

See slide 2 of 18 of this presentation from October 2014 (1.40 MB electronic file size):

http://www.otif.org/fileadmin/user_upload/otif_verlinkte_files/05_gef_guet/03_AG-Entgleisungsdetektion/2014_10/CE_GTDD_2014-A_Annex_V_Presentation_Knorr-Bremse_E.pdf 

http://www.knorr-bremse.de/en/railvehicles/products/trainsafety/edt101.jsp 

http://www.knorr-bremse.com/media/documents/railvehicles/en/p_1216_en_04_edt101.pdf (4 pages, 440 KB electronic file size)

- Paul North. 

"This Fascinating Railroad Business" (title of 1943 book by Robert Selph Henry of the AAR)
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Posted by Paul_D_North_Jr on Sunday, April 5, 2015 10:13 AM

Wizlish, thanks so much for posting that Cresson video. [EDIT: Just 3-1/2 months ago, Dec. 27, 2014 - https://www.youtube.com/watch?v=fBYqdmsxeCQ ]  Bow It belongs in its own thread (and I was there just 2 weeks ago).  More to the point, I've seen the result of that kind of derailment: "All it did was turn over 1 rail.  Oh, by the way - the rail is 4,000 ft. long !"  And it trumps the double-flanged wheel April Fool's Day thread, too - what's really needed is a U-shaped rail for the wheels to run in as in the video - note that everything stayed together and in line.  The opposite side wheel might have even stayed up on its rail, too.  (Wonder what finally got them stopped, and how much of the interlocking got torn up by then . .  .)

Back in the 1960's, there was a heckuva explosion 9actually several) in the SP yard at Roseville, CA - might have killed a couple people, but it certainly destroyed a good portion of the yard.  The cause was eventually attributed to a Navy bomb (bound for Vietnam) falling through the weak floor of a boxcar and rubbing against the wheel until the heat from the friction led to the explosion.  See:

http://en.wikipedia.org/wiki/Roseville,_California#Notable_events  

http://www.trainorders.com/discussion/read.php?1,185297 

From http://www.insensitivemunitions.org/history/railroad-train-fires-and-munition-explosions/ [emphasis added - PDN]: "Fortunately, a person recording train sounds in the mountains outside of Roseville, CA had seen the train. He testified that he had seen a fire in the floor over the wheel of one of the boxcars in that train some six hours before the first explosion occurred in Roseville."

As a result of that and some other high-profile derailments, there was an attempt by the Navy Ordnance people to develop several kinds of sensors to detect derailments, "hot boxes", and other mishaps before they got too far out of control and caused other bomb shipments to explode; all of this was reported in Trains or Railway Age at the time.  I specifically recall that the hot box detector would be mounted in or on the truck frame.  Whether any of this was ever fielded for tests and then made practical (even if not widely adopted), I do not know.

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Posted by Euclid on Sunday, April 5, 2015 9:09 AM
Wizlish,
I have been looking at that second video that you posted.  It too is very instructive.  Notice that the derailed car has its trailing truck turned completely crosswise to the direction of travel, and its wheels are plowing up the ballast.  Notice too that there is a wheelset that has been released from the lead truck, then snagged by the first hopper bin, and is plowing up ballast.  This would indicate that the lead truck is partially destroyed from the derailment.  Yet, even with one crosswise truck plowing ballast, and one partially destroyed truck with one of its detached wheelsets plowing ballast; the car is kept in line by the cars on either side of it. 
Notice what happens when the derailed car hits the grade crossing as it is pulling away from the photographer.  The crossing abruptly straightens the car back up to vertical, but it also snags the derailed truck. 
As this happens, notice the wheelset that pops out from under the car and rolls over to the adjacent track to the right.  Then the car continues running in line and completely upright with a missing wheelset.  All of this is made possible by the fact that the train is being pulled with the slack stretched.  The stretched condition has great influence to keep the derailed car in line.
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Posted by Wizlish on Sunday, April 5, 2015 8:54 AM

Illustrations of the kind of derailment where controlled differential braking might apply:

In my opinion, slack running in is a major cause of these types of derailment progressing to the point that major fouling of adjacent tracks, or 'accordion'-style piling up as drawgear pulls cars laterally, or sequential rollover of cars through torsion.  So detecting a derailed car and controlling the braking rate of both 'ends' in a way that controls slack action, as early as possible after the derailment, should be of benefit. 

I think there should be enough intelligence in the system to recognize when there is a 'sequential' derailment (say, following a picked switch or displaced rail) and do some predictive modulation of the brakes, either by car or by block of cars.

Euclid, there is a valid point about 'instant' detection of derailments.  I do not think this is practical; you'll have to distinguish actual derailment from rough track and the usual kinds of shock, with a robust and cost-effective device.  There are plenty of approaches that would work in theory and on test, like adaptation of machine vision to watch wheel-rail interaction, that are not likely to prove effective in long-term service with typical maintenance even on dedicated 'safety' consists.

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Posted by Euclid on Sunday, April 5, 2015 8:20 AM
Here is a highly instructive video that shows that total chaos does not always commence the instant the first wheel leaves the rail.  Note the large boxcar that is methodically tipping the rail over onto its side as it goes along; and all the following cars are happily running on the side of the rail between the base and the ball.  Nineteen cars derailed and none tipped over or jackknifed:
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Posted by BaltACD on Sunday, April 5, 2015 6:08 AM

Euclid
 
BaltACD
Inertia and Momentum decree what happens after a wheel leaves the rail - no matter how quickly and uniformly the brakes are applied.

 

I am not talking about doing anything directly to the derailed cars for the purpose of influencing them.  I am talking about doing things to the cars still on the rails in order to get them to influence the derailed cars.   

 

As the first wheel leaves the rail, it is at the decree of inertia and momentum, as you say, but there are maybe 100 cars with their 800 wheels still on the rails that are not at that whim.  Those cars and their braking can surely affect what happens after the first wheel leaves the rail. They can exert influence over the train to keep it from parting at the derailment, even if the number of derailed wheels grows.  So the derailed cars will not necessarily be entirely at the decree of inertia and momentum if staying coupled helps keep them aligned rather than jackknifing.    
Just stopping the train quicker will reduce the number of cars going into the pileup if one develops.   
 

I'm not talking about the derailed cars either - I am talking about the rest of the train - both fore and aft of the derailed cars.

Please exit your dream world of train dynamics.

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Posted by Norm48327 on Sunday, April 5, 2015 5:26 AM

And the "One Note Samba" goes on and on. The same never ending song.

Norm


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Posted by Euclid on Saturday, April 4, 2015 10:41 PM
I assume that Larry is referring to the chaos in the tornado derailment as being an insurmountable obstacle to my ideas.  In the tornado video, the tornado forced several cars off of the track almost simultaneously.  The first car to derail was back maybe 4-6 cars behind the engine.  You can hear the train dynamite when that first car derails.  Then cars followed it off in both directions from there all the way to the engine, and all the way back to the tank car.
I agree that, even without the broad force of a tornado, a derailment can instantly lead to a massive, chaotic pileup.  Even though there is value in preventing the parting for as long as possible, it is possible for a derailment to begin with a drawbar being pulled out and derailing the train, for example.  In that case, the train parts even before the derailment begins.  Certainly it will instantly begin to jackknife as soon as the derailment begins.  It would be impossible to shove a derailed car down the track and expect it to run straight.
But there are many derailments that immediately lead to dragging the derailed car for considerable distance without tearing up the track enough to derail the following cars.  That status can persist for a while until it is perturbed enough to start tearing up the track enough to derail more cars; or the first derailed car can suddenly break up the derailed truck and pass pieces back under following cars and derail them.
But while the car is being dragged, there is a window of opportunity to stop the train before it derails more cars or progresses to a pileup.       
Certainly there can be instant, extreme chaos starting the instant a derailment begins and the system I propose may not help at all in such cases.  It is not intended to be an infallible way to prevent all train wrecks, just like air bags are not infallible in preventing all injuries or death.      
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Posted by Euclid on Saturday, April 4, 2015 9:57 PM
BaltACD
Inertia and Momentum decree what happens after a wheel leaves the rail - no matter how quickly and uniformly the brakes are applied.

I am not talking about doing anything directly to the derailed cars for the purpose of influencing them.  I am talking about doing things to the cars still on the rails in order to get them to influence the derailed cars.   

As the first wheel leaves the rail, it is at the decree of inertia and momentum, as you say, but there are maybe 100 cars with their 800 wheels still on the rails that are not at that whim.  Those cars and their braking can surely affect what happens after the first wheel leaves the rail. They can exert influence over the train to keep it from parting at the derailment, even if the number of derailed wheels grows.  So the derailed cars will not necessarily be entirely at the decree of inertia and momentum if staying coupled helps keep them aligned rather than jackknifing.    
Just stopping the train quicker will reduce the number of cars going into the pileup if one develops.   
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Posted by Euclid on Saturday, April 4, 2015 9:52 PM

tree68
 
Euclid
But, as I mentioned, the main point of this system is to stop the train or reduce its speed before the train parts, and also to help prevent it from parting.     

You need to go back and watch that video I posted the link to a bit ago.  Watch it very closely.  Several times, even.   It gives lie to many of the things you presume will prevent derailments, etc.

Oh, I did not know that you posted it.  I saw it posted by BaltACD.  But in any case, I am extremely familiar with that tornado derailment.  I have watched it at least 50 times, and start/stopped it at least 200 times.  I have turned it inside out in order to learn exactly what was happening.  So how does it give lie to my ideas about what will prevent derailments?

 

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Posted by Wizlish on Saturday, April 4, 2015 9:42 PM

Here is the reference (from March 24 at 10:50 am):

tree68
Here's your derailment dynamics right here:

https://www.youtube.com/watch?v=a-smEEHYdGQ

This is the well known video of the train hit by a tornado.

I don't think this is particularly demonstrative of the kinetics of most derailments.  Here the cars were bodily toppled over (still 'railed' to the last!) almost incidentally taking the adjacent ends of the train off the rails as they went.  One might argue that if the head end had not stopped short in emergency, the following part of the train would have come to a stop by itself once the parted-hose emergency braking had taken hold. 

Euclid's system is assuming that the early moments of a derailment don't result in a catastrophic motion of the cars, either in massive yawing or massive deceleration, and that if through nothing else but momentum the car continues in a straight line, coupled at both ends, with flange contact with ties and ballast continuing to make the truck frame track approximately straight.  The film of the Army tests 'optimizing' sabotage during WWII establishes how difficult it can be to produce an actual derailment even with large pieces of the rail missing. 

It's that scenario -- one or more cars with wheels now bumping along the ties rather than smoothly on the rails -- that the differential-braking system is intended to address.  I would be tempted to look into methods for assuring the integrity of trucks subjected to this -- locking the wheelset bearings to the sideframes, for example, or restricting the yaw rotation rate of the truck relative to the underframe, or providing some default detented centering of the truck frame relative to the underframe if a derailment is detected -- as things that might be secondarily beneficial.

I also think that differential-braking apparatus, if designed correctly, would help with other situations, notably the tendency to 'snatch a knuckle' during emergency braking.  If braking effort is so proportioned in a given consist that the instantaneous load at any coupler is kept under control, but overall also modulated to produce high retarding force up to the point of wheelslide, you still have high 'enough' braking effort to produce a minimum-distance stop, but have virtually eliminated derailment or separation problems from things like dynamiters... without necessarily going to the expense of two-pipe electropneumatic braking.

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Posted by Euclid on Saturday, April 4, 2015 8:36 PM

What video is that?  I don't recall it and don't readily find it.

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Posted by tree68 on Saturday, April 4, 2015 8:12 PM

Euclid
But, as I mentioned, the main point of this system is to stop the train or reduce its speed before the train parts, and also to help prevent it from parting.     

You need to go back and watch that video I posted the link to a bit ago.  Watch it very closely.  Several times, even.   It gives lie to many of the things you presume will prevent derailments, etc.

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Posted by tdmidget on Saturday, April 4, 2015 4:01 PM

Bucky, why is it that your solution to every problem seems to be the addition of nonexistant electronic whizbang doodads to the one of the the most reliable , simplest, and efficient machines, ( railcar) in history? And applied in areas where it is impossible to even keep a coat of paint? None of your ideas exist, or are well thought out, or can be practically implemented even if they did exist. Time to come back to reality.

Maybe take a look at your ideas on the the Nevada collision of the Southwest Chief to see how in touch with reality your ideas are.

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Posted by BaltACD on Saturday, April 4, 2015 2:16 PM

If if's and but's were candy and nuts, what a wonderful world it would be.

Inertia and Momentum decree what happens after a wheel leaves the rail - no matter how quickly and uniformly the brakes are applied.

 

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Posted by Euclid on Saturday, April 4, 2015 11:31 AM
Dave,
To your first point:
The point of the derailments sensor is to detect a derailment the instant it happens.  When it does that, it will begin the braking.  So, for practical purposes, the braking begins the instant the derailment happens, even if it does technically lag for a fraction of a second.
To your second point about the three braking rates:
If the derailed cars stay together, they will be subject to the kinetic energy of the cars ahead of the derailment pulling on them.  I agree that once enough cars are derailed, their resistance will exceed the braking resistance of the cars ahead.  Once that happens, the tension between the derailing cars and the cars ahead of them will become so great that it will part the train somewhere in that range of maximum tension.  However, it is not a forgone conclusion that enough cars will derail to meet that threshold.  And even if it does, there still may be enough time beforehand to dissipate a large amount of the kinetic energy that will feed into the derailment, thus resulting in fewer cars derailed than without this system     
To your third point:
The cars behind the derailment could run into the cars ahead of it if the cars behind the derailment are all on the rail; and if the derailed cars are still coupled to the cars on the rail ahead and being dragged by those cars ahead still on the rail. 
But, as I mentioned, the main point of this system is to stop the train or reduce its speed before the train parts, and also to help prevent it from parting.     
The main point I was making about the wire is that even if it breaks, it can still function on either side of that break.  So, in that sense, it differs from the control attributes of the train line in conventional air brakes.  But as I said, I see little need for any modulation of the brake forces that would need to be communicated to the cars through the wire.   
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Posted by dehusman on Saturday, April 4, 2015 10:41 AM

Euclid
 So the derailment sensors tell the system to begin the instant a derailment happens, and from there on, the system is on its own without any further commands through the wire.  

Not the instant it happens, braking will begin the instant its detected.  It is detected whenever the conditions exceed whatever limits you have set up to indicate there is a derailment.
There are three braking rates, the head end, the rear end and the derailed cars.  The fastest deceleratio rate is that of the derailed cars.  They will stop faster than the rear of the train.  Once the cars leave the rail, you lose contrl of their direction and braking rate.  They are unguided.
 
Another point to consider, however, is that even with the wire being broken, it still offers a continuous line of control on either side of the break.  The difference in brake force called for in this system will come from reducing the brake force on the cars ahead of the derailment. 
What advantage is that?  The rear of the train isn't going to run into the head end, its going to hit the pile of cars with no track under it that is between the head end and the rear end.
 

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Posted by Euclid on Saturday, April 4, 2015 9:24 AM
I am eliminating the following two features of this differential braking concept:

1)    Wireless control.

2)    Adjusting braking according to train location.

 
These items are not essential, and either or both can be developed later if there is a need for them. 
 
Most of the advantage of the differential braking that I suggest will apply before the train separates.  That advantage will then continue to help prevent a separation.  In certain cases where separation does occur, this system will help prevent the cars behind the derailment form colliding with the cars ahead of the derailment.  This would be in cases where the trailing truck of a car derails, and separation occurs at the joint behind it, leaving all the cars behind the derailed truck still on the rails. 
Regardless of separation, the differential braking would begin the instant the first wheels derail.  That is the instant that ECP will begin the differential braking by a signal through the wire.  At any point, thereafter, the wire might break.
Therefore, any modulation of braking after the derailment is detected will have to be programed into the logic of each car as a predetermined response.  So the derailment sensors tell the system to begin the instant a derailment happens, and from there on, the system is on its own without any further commands through the wire.  
Research would be needed to learn whether the system would ever need any modulation.  If it does, it might be programed in as part of every response.  Or perhaps, modulation might be advantageous in relation to an external factor such as train speed.  If so, speed could be sensed on every car and communicated to the ECP control even if the wire is broken at the point of derailment. 
Another point to consider, however, is that even with the wire being broken, it still offers a continuous line of control on either side of the break.  The difference in brake force called for in this system will come from reducing the brake force on the cars ahead of the derailment.  So there is still the possibility of modulating the brakes on these cars through the wire from the head end even though the wire is broken at the point of derailment.             

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