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Washington DC To Return To Automatic Metro Trains
Bruce66423 (1678196) writes with news of interest to anyone with reason to ride mass transit in the U.S., specifically on the D.C. Metro system: After a crash some five years ago, automatic operation was abandoned. Now however replacement of 'faulty' modules means that moving the whole system on to automatic operation can happen. One quote is depressing: "And because trains regularly lurch to a halt a few feet short of where they should be at platforms, Metrorail riders have grown accustomed to hearing an announcement while they're waiting to board: 'Stand clear. Train moving forward.'" That never happens on the London underground with human operators? What's wrong with American drivers?
Never seems to happen in New York. What's the problem in DC?
> What's wrong with American drivers?
DC's metro trains were designed to be operated automatically the vast majority of the time. Hence, the acceleration and braking systems were optimized for automatic operation (as opposed to manual operation) and it is difficult for a human driver to control the train's movements precisely and smoothly.
For example the central line has been automated since the 90s. Drivers there just to go on strike
The Red Line crash was not computer-related. The signalling system for the Washington Metro is a classic electromechanical relay-based system. Just like the New York subways. The Red Line crash was caused by a failure of a track circuit for detecting trains, trackside equipment using an audio-frequency signal sent through the rails and shorted to the other rail by the train's wheels. All those components are pre-computer technology.
As with most railway systems, manual driving isn't enough to prevent collisions, because stopping distances are often longer than visual distances. That was the case here.
The Washington Metro had been sloppy about maintenance of trackside equipment. They do have a central computer system, and it logs what the relay-based signal systems are doing, although it can't override them. They had logs of previous failures, and should have fixed the problem.
Is this the actual case?
No, except for the bit about it being underfunded and therefore not as well maintained as it should be. Which is a shame, because it's a fantastic piece of infrastructure, much nicer to ride than (say) most of the London Underground or the NYC Subway.
It used to be automated, but the nixed that. It's not audio equipment. The driver today was clear and intelligible; I wanted to walk to the front and thank her.
First, as of 2010, DC was about 50% Black, 39% White, plus everybody else. Source: http://en.wikipedia.org/wiki/D.... As a (White) DC resident who moved back here a couple of years ago, one of the things I enjoy about the Metro is the casual, random, cheerful conversations I have with my fellow riders who happen to be Black. Second, I live in DC and ride Metro regularly. Occasionally there are annoying people (often Black), but very rarely threatening ones. Cell phone theft on the Metro is a danger here, like most places (and police don't seem to care anywhere). Third, Metro needs to better enforce its rules against food and drink (and smoking) in the system. In effect, Metro no longer enforces that rule so the cars can be a mess. I encountered a White guy smoking on a platform earlier this year and asked him to put it out. He blew me off, quite obnoxiously.
There were a bunch of cases of 8 car trains being stopped by the driver as if they were a 6 car train. This left one car of people in the tunnel. It was decided that instead of relying on the train driver to remember how long of a train they are driving, all drivers would be required to pull up to the end. (The right decision IMO.)
The main controls on a train are to go forward and backward. Hardly something that needs advanced artificial intelligence and 3D spacial comprehension. It is basically a one dimensional problem when operating a train, and monitoring the rails to make sure that one dimension situation doesn't change into a 3D problem. Sure, there is monitoring the equipment on the train itself where the motors are far more complex, but even that has its limits and isn't too complicated.
I always wondered why they had drivers. How hard is it to start and stop a train? I asked one of my Japanese coworkers why he thinks they have drivers, what with all the technology in Japan and all, and his reply was very insightful: "they have drivers so they can blame/fire someone if something goes wrong".
THAT is why trains have drivers.
None of the Underground lines are driverless. The ones you list are GoA level 2 (i.e., opening/closing doors, starting the train, and emergencies are handled by the driver). Go look in the cab of any of them, they all have drivers!
Even the DLR is a GoA level 3 system, as the "attendant" handles door closing and emergency driving of the system.
The only GoA level 4 systems (which are truly driverless and can operate without any trained staff onboard) in the UK are the people movers at Heathrow T5, Gatwick, and Stansted.
I suspect what Jmstuckman meant was that the controls were not intuitive to humans, or have a range of control that is awkward. In other words, imagine that the gas pedal on your car had 1 mm of travel and you had to manually set 3 different interlocks to change to reverse gear, and you had a significantly obstructed viewpoint, since it was only meant for automated control. Then you too would have a hard time with the simple 1-dimensional control as well. Getting within a foot of the platform target would probably be good enough if it took significant effort on touchy controls to adjust.
Disclaimer: the only train I have controlled is in MS train simulator.
The correct decision would actually be to fire anyone retarded enough not to know which vehicle they're driving.
-1 disagree is not a modifier for a reason. -1 troll, flaimbait, redundant, overrated are NOT acceptable substitutes.
The automatic system was fine for nearly 40 years. The upgrade process killed nine people and injured 80 and caused a safe system that ran reliably for nearly 40 years to run in "manual" mode for five years because of a maintenance error.
Several depositions from railroad workers who were tasked with upgrading Metro's nearly 40-year-old system mentioned a real problem. The signals were "bobbing." This happened because the older signal system was being replaced with a different vendor's technology in two phases with catastrophic results.
In phase one, the lineside signal cabinet equipment was replaced but the original track sensors were left. In other cases, it was reversed: the track sensors were replaced but the lineside signal cabinet equipment was original. In both cases the vendor was different and not totally compatible.
Naturally, as we would expect, the two different vendors' equipment was not interfacing perfectly. This caused signal "bobbing," where track occupancy would "bob" from red to green repeatedly. Trains would vanish from the system. Phantom trains would appear in the system.
This massive oversight reported in the depositions wasn't really taken seriously in the press nor by the accident investigation. From this point of view, the system failed due to incompatible equipment made to interface in order to save money and service disruptions. They didn't interface properly, and people died as a result. Nobody seems to care about what appears to be the real problem: incompatible vendors made to interface to save time and money.
But we now have faster trains with shorter headways that sometimes fail to stop at the correct spot in stations, so we have that going for us. At least the lineside cabinet equipment and track sensors are now from the same vendor, eliminating the problem that killed those people and put hundreds of thousands of others at risk for a couple of years until that deadly day in 2009.
Kriston
In contrast, the Danish Copenhagen Metro went into operation late 2002. After extensive teething problems during the first years of operation, I was very surprised at just how well this driverless system now functions. Additionally, the design and architecture is extremely futuristic. The above ground sections linking the CBD with the airport are more reminiscent of scenes from Star-Trek. Though quite small (2 lines), it is currently undergoing a city-wide expansion phase. In cases of extreme winter weather, the above ground sections sometimes have to be manually controlled to ensure the system does not interpret heavy snow as an obstacle. Despite this requirement, there is no actual operator cabin, so passengers can sit right at the front and enjoy the scenery ahead through the large glass windows. For those looking for a solid and efficient metro transport solution, look no further.
I live in Nuremberg, Germany. 2 of 3 subway lines are fully automatic. They run much more often than with drivers, and this is actually MIXED operation: the third line, that is still driver operated, shares the tracks on the middle section through the city. Nuremberg was the first city to have such a mixed-mode subway.
They are on time for the most part, stop within a few cm of where they are supposed to each time, and are just a normal part of life. I've read about an occasional hiccup but never experienced one myself, and I don't think it's more than it would be in the "old system". The biggest stops were due to worker strikes, not technology issues. They didn't lay off anyone, by the way.
Anyway, it is just unexciting business as usual for me any more, nothing special.
Video (1min): https://www.youtube.com/watch?...
http://www.railway-technology....
http://en.wikipedia.org/wiki/N...
much nicer to ride than (say) most of the London Underground
You mean you don't like the Northern Line at rush hour? Do you have some weird objection to having your face jammed into some giant's armpit for 30 minutes in 35 degree heat or something?
SJW n. One who posts facts.
The elevators are obstinate, bullheaded, piggish, among many other dysfunctions....;)