ATC question

[Nick_Burman]

Hi all,

 

In a line equipped with ATC (in Japan that means no lineside signs or signals, all information - track speed, etc.- being conveyed through indicators in the cab), how does the motorman know where and when to slow down? I've been driving trains in simulators (mainly BVE) and in those lines fitted with ATC I have a hard time trying to figure when the system will kick in and slow me down (or plain stop). In one simulation I actually let the system handle braking for me as the rate os deceleration is pretty smooth and gradual, but in others the ATC can be pretty brutal, with resulting passenger complaints...

 

 

Cheers NB

[bikkuri bahn]

Typically in the cab of an ATC-equipped train the speedometer will be mounted centrally and prominently.  Around the meter ring will be a series of LEDs which will indicate the fastest line speed permitted.  The driver will adjust speed/brake as the indication changes.  It allows for more precise (and closer train spacing) than ATS, as the permitted speed is calculated by the system, rather than interpreted by the driver through lineside signals.  With digital ATC, the performance and braking characteritics of each individual train is calculated, allowing even more precision.

 

Tobu 50050 series on the Den-en toshi Line:

[Nick_Burman]

Typically in the cab of an ATC-equipped train the speedometer will be mounted centrally and prominently.  Around the meter ring will be a series of LEDs which will indicate the fastest line speed permitted.  The driver will adjust speed/brake as the indication changes.  It allows for more precise (and closer train spacing) than ATS, as the permitted speed is calculated by the system, rather than interpreted by the driver through lineside signals.  With digital ATC, the performance and braking characteritics of each individual train is calculated, allowing even more precision.

 

Tobu 50050 series on the Den-en toshi Line:

 

Thanks BB, this I have understood. However, on the simulations as soon as the speed indication changes the brakes come on immediately - sometimes in a rather harsh way. Does this happen on the real trains or does the system give the motorman time to react before taking over and forcing a slowdown?

 

Cheers NB

[bikkuri bahn]

I'm not sure, but I think the system gives the drivers a few seconds to adjust before the brakes are automatically applied.  Perhaps the simulator is set to be more sensitive for more challenging game play, such as requiring you to learn the road and anticipate changes before they happen, which sounds more ATS oriented.

[The_Ghan]

Geez!  Even I could drive one of these !!!

 

Cheers

 

The_Ghan

[bikkuri bahn]

With ATO operation, you just have to push a button after the doors have closed- the electronics take care of the rest (Tsukuba Express, Sapporo Subway Tozai Line).  Pretty boring, if you ask me- I'd likely fall asleep.

[westfalen]

Geez!  Even I could drive one of these !!!

 

Cheers

 

The_Ghan

When I was learning to drive one of the tutors said he could teach his 90 year old grandmother to drive a train, the biggest part is 'learning the road'.

 

I think driving under ATC would take a bit of getting used to, you'd have to react faster because the speed could change at any time, on a normal train the signals and speed boards are always in the same place.

[westfalen]

With ATO operation, you just have to push a button after the doors have closed- the electronics take care of the rest (Tsukuba Express, Sapporo Subway Tozai Line).  Pretty boring, if you ask me- I'd likely fall asleep.

I was talking to a driver on the Singapore Metro when I was there a few years ago, he said when it was raining they have to cut in the controls and drive manually because the automated system couldn't handle slippery rails.

[200系]

Thanks BB' date=' this I have understood. However, on the simulations as soon as the speed indication changes the brakes come on immediately - sometimes in a rather harsh way. Does this happen on the real trains or does the system give the motorman time to react before taking over and forcing a slowdown?[/quote']

 

I'd say it depends on the ATC system, there are give or take 14 variants of ATC in operation in Japan. the ATC systems used on the Shinkansen (ATC-1, ATC-2, DS-ATC and ATC-NS) work in semi ATO operations, the ATC system takes care of braking (speed restrictions and aproach to stops) while the driver is responsible for accelleration and stopping the train at the right platform indicator (ATC doesn't give brake command under a certain speed unless the driver doesn't stop in time). So yes for Shinkansen the way it is simulated (at least for the Tokaido Shinkansen in BVE) is more or less correct, as far as I know. I don't know if this is also correct for other ATC systems, I'd say it's called Automatic Train Control for a reasson.... But I might be wrong :)

 

hope this helps you.

[marknewton]

When I was learning to drive one of the tutors said he could teach his 90 year old grandmother to drive a train, the biggest part is 'learning the road'.

 

You're not wrong. That's been my experience as well. It's interesting to see how many DTs quickly become proficient in their train handling, but struggle with road knowledge. Even the old hands need the occasional refresher job to keep them up to speed.

 

I think driving under ATC would take a bit of getting used to, you'd have to react faster because the speed could change at any time, on a normal train the signals and speed boards are always in the same place.

 

Interesting comment. On my line we're in the middle of a big resignalling project, and some of the sticks have been moved, as well as car markers on platforms. As well as that, the speed boards are being changed to a new pattern, so there is some potential for confusion. We're also starting an ATP trial, which should make life very interesting! 

 

Cheers,

 

Mark.

[westfalen]

Interesting comment. On my line we're in the middle of a big resignalling project, and some of the sticks have been moved, as well as car markers on platforms. As well as that, the speed boards are being changed to a new pattern, so there is some potential for confusion. We're also starting an ATP trial, which should make life very interesting! 

 

Cheers,

 

Mark.

Up here, a few months ago now, they completed the Richlands Line and resignalling beween Corinda and Darra where there are now four tracks with bi-directional signalling which continues all the way to Richlands and you've got to be on the ball as to which track you're on because control seems to put you through crossovers just because they can. Not long after the new timetable started a train left Darra on a yellow signal and the driver had a spad at the next one because 99 times out of ten it steps up to green as you approach. An inspector who happened to be in the rear cab drove the train back to the platform and took over the train then immediately had another spad at the same signal because he was looking at the one on the next track.