Norfolk Southern installs "new" detection devices near the recent East Palestine derailment

[BaltACD]

blue streak 1

One problem that am not aware is being addressed by all of these detection systems.  That is partial wheel failures.  Some wheels have a diameter up to 42 inches.  That means up to ~~ 131 inches of travel for one revolution. 36 inch wheel 113 inches of travel.  It does not appear that there is any visual system that can survey a wheel for any partial failure or loss of mass.  Am I missing something?

That is what Wheel Impact Load Detectors are for. A wheel that has lost mass will lose it from the rim/tread area and thus create a level of impact with every revolution of the wheel.  WILD's also detect slid flat wheels as their flat spots generate impact passing through the detector.

I am guessing that WILD's are a part of these 'super detector/inspection' sites.

[tree68]

BaltACD

That is what Wheel Impact Load Detectors are for.

Anyone who's been trackside when a wheel with a flat spot is passing knows you can hear them from several cars away.

I've heard that an informal measure of the degree of a flat spot is if you can hear it from seven cars away, it's actionable.  You won't find that in any rule books.  The ultimate measure is a ruler.

One hundred thirty one inches is almost 11 feet.  An auto rack (a common place to find flat spots) is 80+ feet - which means that in one car length, that flat spot will hit 7 or 8 times.  

I'm sure the WILD detectors will sense such problems, even from the vantage point of a foot or so of actual detector.

As Balt points out, an out-of-balance wheel will also generate a certain amount of impact, especially at higher speeds.  It's up to the engineers (design types, not locomotive) to develop the impact parameters that require action - something they likely have already done.  

[jeffhergert]

These detector arrays may or may not give an immediate alert to stop.  I would guess they would if they detected a defect that required immediate attention.  However, I think these are designed to catch equipment that is in the early pase of failure, something that can make it to the next point that has car men.  That's assuming that they haven't cut off most of the car men and that someone doesn't try to "extend" the distance beyond the next repair point.

Broken wheels may set off a dragging equipment detector.  When opearting on concrete ties and a visual inspection for dragging equipment doesn't turn up a defect, an audible inspection is required.  The conductor places him/herself 20 axles ahead of the indicated axle, have the train pulled by 20 axles past the indicated axle, listening for any unusual sound from the wheels.

Jeff 

[dehusman]

Euclid

QUESTION:  When the system finds a problem, does it make the decision to stop the train? 

Most of the newer systems I am familiar with the system tells the train to stop in most cases.   Older legacy systems may send results to a central desk and they tell the train to stop.

If so, does the system stop the train?

Yes.

If that is the case, do the humans decide whether the system command to stop the train is correct?

 

Yes to the extent that the stop and the results of the stop are reviewed to determine if the stop was valid or not (was a defect found).  If not then the the defect trigger conditions are validated to see if the they should be changed.

If the humans conclude that the stop command is incorrect, do they then intervene and overrule the system?

In the systems I am familiar with, yes, but not on a real time basis.

[dehusman]

tree68

With PTC, I suppose the capability exists to enforce such a stop, assuming good communications all along the data path

PTC is irrelevant.  Tains have been stopped by defect detectors automatically notifying the trains for the last 40 years.

[Overmod]

dehusman

Tree68

With PTC, I suppose the capability exists to enforce such a stop, assuming good communications all along the data path...

PTC is irrelevant.  Trains have been stopped by defect detectors automatically notifying the trains for the last 40 years.

Defect detectors haven't been 'notifying the trains'; they've been notifying the train crews.  What tree is saying is that PTC can physically enforce a detector indication with (presumably appropriate) train braking directly.

[blue streak 1]

blue streak 1

One problem that am not aware is being addressed by all of these detection systems.  That is partial wheel failures.  Some wheels have a diameter up to 42 inches.  That means up to ~~ 131 inches of travel for one revolution. 36 inch wheel 113 inches of travel.  It does not appear that there is any visual system that can survey a wheel for any partial failure or loss of mass.  Am I missing something?

 This question is not about flat spots that all posters have assumed. Ot can not be detected of a crack from axel outward to wheel tread. There can be fractures on the wheel itself that cannot be detected by a wild detector.  Although not as prevelant as flat spots there certainly have been instances.  

[BaltACD]

blue streak 1

 

blue streak 1

One problem that am not aware is being addressed by all of these detection systems.  That is partial wheel failures.  Some wheels have a diameter up to 42 inches.  That means up to ~~ 131 inches of travel for one revolution. 36 inch wheel 113 inches of travel.  It does not appear that there is any visual system that can survey a wheel for any partial failure or loss of mass.  Am I missing something? 

 This question is not about flat spots that all posters have assumed. Ot can not be detected of a crack from axel outward to wheel tread. There can be fractures on the wheel itself that cannot be detected by a wild detector.  Although not as prevelant as flat spots there certainly have been instances.  

I believe the CSX super detector sites have high speed cameras looking at the axle wheel interface from their inside connection point - looking for cracks or other defects at that location of stress.  NS and the other carriers may have the same detection systems in place.

At present CSX has their 'super detector' sites on the main routes into Rice Yard at Waycross, GA - one of CSX's main car repair terminals as well as a high volume hump yard.  The super detector site also inspect the through trains that do not stop or work at Waycross.

[Euclid]

What most people are talking about here is the status quo detector practice, with detectors placed at regular intervals of say 30 miles apart.  With the East Palestine wreck, the detector intervals have come to be questioned as to whether they should be shorter.

 

However this thread began with the topic of the new A.I. detector “tunnels” with greatly enhanced detection capabilities compared to the current state of the art.  But I doubt that these new detector tunnels are going to be placed at the suggested closer intervals than what is current practice of the historic detectors.

 

So, based on that observation, I wonder if the new A.I. tunnel detectors are missing the point of today’s detector shortcomings.  If the problem is detectors spaced too far apart, that means that they allow too much time for hot bearings and other impending failures to develop. 

 

Replacing those current detectors with more accurate and capable detectors, although spaced much further apart, seems to focus on a non-problem while ignoring the real problem of too much time and distance between detector inspections. 

[dehusman]

blue streak 1

This question is not about flat spots that all posters have assumed. Ot can not be detected of a crack from axel outward to wheel tread.

Those are tested by ultrasonic detectors that "ping" the wheels and if they "ring" the wheel is good, if it doesn't the wheel may be cracked.  The UP N Platte yard is equipped with one of those that tests inbound coal trains.  It is affectionally known as the "crackhouse".

[dehusman]

Euclid

Replacing those current detectors with more accurate and capable detectors, although spaced much further apart, seems to focus on a non-problem while ignoring the real problem of too much time and distance between detector inspections. 

Not all detectors detect the same things, they may detect different defects with different failure modes and different rates of development.  There are some defects that may be fine testing once a trip and there may be other defects that need to be tested every 10-20 miles.  For example wide load detectors are typically only installed ahead of restricted clearance points.

[jeffhergert]

Currently defect detectors do not interact with PTC.  At most would be if a detector is linked to a hold signal that needs to be manually cleared if a defect is detected.  Other than that, PTC does not react to a detector alarm.

Not that it couldn't be integrated in the future. 

Jeff

[Euclid]

dehusman

 

 

Euclid

Replacing those current detectors with more accurate and capable detectors, although spaced much further apart, seems to focus on a non-problem while ignoring the real problem of too much time and distance between detector inspections. 

 

 

Not all detectors detect the same things, they may detect different defects with different failure modes and different rates of development.  There are some defects that may be fine testing once a trip and there may be other defects that need to be tested every 10-20 miles.  For example wide load detectors are typically only installed ahead of restricted clearance points.

 

Yes, I understand that.  I am thinking mostly about the hot bearing detectors since NS is championing this new system and, and considering their experience with East Palestine putting their hot bearing detectors in the spotlight after failing to prevent the wreck at East Palestine.   

 

Now, they have introduced their new A.I. multi-function detector tunnels as being a powerful advancement in the wayside detection art, so I am wondering how it would have changed the outcome of the overheated bearing, and its presumed connection to the East Palestine wreck. 

 

It would be interesting if someone published a non-A.I. explanation of exactly what the new system detects, how it does so; and how it interacts with the “Subject Matter Experts” referred to in the news article. 

 

From those articles, I conclude that the new A.I. tunnel system merely hands the scan data to the Subject Matter Experts, and they alone will decide what action to take, if any.  So humans will decide according to the conflicting risks of acting on a false alarm versus causing a derailment by not acting.  I wonder if the A.I. will at least weigh those risks and rank them as a reference for the humans. 

[dehusman]

Euclid

so I am wondering how it would have changed the outcome of the overheated bearing,

Probably not at all since visual band cameras won't detect roller bearing failures.  They will detect other stuff, but not failing bearings.

[CatFoodFlambe]

All the technology in the world is useless if NS doesn't have enough employees to act on the information provided.  

[Overmod]

CatFoodFlambe

All the technology in the world is useless if NS doesn't have enough employees to act on the information provided.

At least in this respect, NS is way ahead of the curve.  They have several levels of AI/ES running on the raw data and in any developing 'incidents' that might proceed to concern, and are actively developing more; there is nothing groundbreaking required to implement rapid and nuanced high-level reporting to dispatch and train crews -- likely far faster and with less confusion than routing 'big data' through some sort of incident desk so employees can pick up a phone.

Doesn't help the actual bad-bearing detection much, if at all -- but it does promise the necessary quick and positive response once they actually provide failing-bearing detection that works.

[Euclid]

Initially,  I had concluded that this new system was comprehensive sensing and detection with thermal, audio, and vibration detection for things like hot bearings, flat spots, broken wheels, cracked wheels, truck hunting, axle defects, overweight, etc.

 

But what this new inspection tunnel is actually doing, is only taking photos of the train.  So this is only a visual inspection as the inspector in the link below is doing.  The only difference is that the new tunnels will do it on the fly, and that will be much faster than the walking human inspector.   

 

However, I don’t see why the article talks about fewer false positives.  This type of inspection is not as urgent as detecting a suddenly developing running emergency such as a failing bearing, which can quickly cause a derailment.  So it is hard to understand how the human inspector can see what he believes to be a problem in need of attention, and have that decision turn out to be a “false positive.”  The walking human inspector is more likely to miss a problem rather than to see something he falsely believes to be a problem.  A walking human inspector missing a problems would be a “false negative.”

 

A false positive is more likely to result from an automatic hot bearing detector being calibrated to error on the side of catching every potential bearing issue versus on the side of preventing the unecessary stopping and delaying of trains.

 

Visual inspection by walking human inspector:

 

https://www.youtube.com/watch?v=96SZ0QleXjw

 

[dehusman]

Euclid

So this is only a visual inspection as the inspector in the link below is doing. 

Yes and no.

There are lots of things that a yard inspection won't catch because a yard inspection is done in a yard, with the car stationary and cold.

On the other hand there are lots of things that will only be caught with the car moving and there are defects that can happen after the car departs a yard (hot bearings, truck hunting, shifted loads, dragging equipment, etc.)

[Euclid]

Apparently, the system takes 1,000 photos of each passing railcar, and then “reads” those photos to find various problems.  It is programed to know the normal conditions, and so it compares what is shown in the photos to what is normal. 

 

For instance to inspect for truck hunting, the system would analyze images of the trucks and look for locations of the truck details that would indicate that truck is wobbling in a rotational pattern about its axis on the truck center pin.  It would show a hunting truck to be abnormally changing its position as it passes the cameras. 

 

I doubt it would detect cracked wheels, but it could detect wheels with broken out material, including wheels with excessively flat spots on their treads. It would not hear the impact, but it could see the missing material on a condemnable flat spot.

 

For hot bearings, it could at least detect smoke or fire.  It also will easily detect dragging equipment.  That could be things like air hoses being low enough to touch grade crossing decking, or derailed-dragging wheelsets.  For critical defects like the latter, I would expect the system to issue an immediate alert to stop the train, and then the human subject-matter experts would address the issue. 

 

A large train could generate a quarter million photographs, and each photo could contain a very large number of target results.  I suppose the results would be presented in a range of charts and graphs from general overview to specific problems that call for varying degrees of action within varying future timeframes.

 

There are potential emergencies such as a derailed-dragging car, overheated bearing, or extreme wheel problem that the system would readily detect, but is unlikely to detect in time to avert a derailment or pileup; because too much time will pass before the train reaches the next detector tunnel. 

[dehusman]

Euclid

Apparently, the system takes 1,000 photos of each passing railcar, and then “reads” those photos to find various problems. 

These type detectors on other railroads also have the "normal" detection sensors (hot journal, dragging equipment, wheel impact, etc) in addition to cameras or other visual sensors.  I would imagine that the NS's do also, they just weren't mentioned because it wasn't sexy new technology, so wasn't part of the press release.