How do the R142 Strip Maps work?

[lilbluefoxie]

How do the R142 Strip Maps work? What does it look like underneath the panel with the strip maps? How does the train know where it is?

 

Also is there announcements for if somehow those trains wound up there?

[MTR Admiralty]

There are announcements for those routes, I believe. Not so sure about the shuttle.

As for how it works, I am not so certain.

[Y2Julio]

(If I remember correctly from what a T/O on the board explained) The Doppler radar system which is used to measure the trains speed is also used to count the revolutions of the wheel/axle. The system already has the number of revolutions that a train will make between stations, so say (just pulling a random number), it's 1,000 revolutions between Union Square and Astor place, once the system detects that the train has made those amount of revolutions it will be like "Ok, the train is now at 14th St, play the station announcements." This system is not fail proof either. If the train has any wheel slippage or the radar system gets thrown off track by whatever reason, then the train computer system becomes out of sync and that's when you get the trains which are announcing the wrong stops.

[Maserati7200]

It measures the distance by wheel revolutions.

[Zman]

It's measured by a radar type device which measures distance and reports it to the train's computer. The problem comes when the sensor becomes caked with steel dust or other particles. When this happens, the train can either over or underestimate the distance travelled which throws the train's location off the mark. I've operated trains which would say that I've gone past Jefferson St by 1000 feet even though I'm currently in that station with the doors open.

[KTrainExp]

Can you reset the program to fix up the error?

 

For example, let's say you're at 96th street on the line and it says you're 500 meters away. Can you reset the program and let it say that you're at 96th street dead on?

[Zman]

Can you reset the program to fix up the error?

 

For example, let's say you're at 96th street on the line and it says you're 500 meters away. Can you reset the program and let it say that you're at 96th street dead on?

 

Yes, but if your system is defective you'll have to reset it, then reset it, then reset it again. And you have to do it all while in the station with the doors open so you lose time. One time on the , we had to reset it four times before we even reached Broadway Junction. After the fourth time we just turned off the announcements.

[KTrainExp]

Yes, but if your system is defective you'll have to reset it, then reset it, then reset it again. And you have to do it all while in the station with the doors open so you lose time. One time on the , we had to reset it four times before we even reached Broadway Junction. After the fourth time we just turned off the announcements.

 

I understand now. Is this a daily thing where drivers or conductors reset the train, or is it an uncommon, but not rare thing. Plus, how long does it take to reset the train? If it's a few minutes, then drivers could easily set it while sitting at the station waiting for the terminals to empty out.

[lilbluefoxie]

How does the map thing work itself, what do they do to change the route, do they have to take that whole panel out and put in a new one, or is it like an overlay and underneath is a long row of lights and things

[Maserati7200]

How does the map thing work itself, what do they do to change the route, do they have to take that whole panel out and put in a new one, or is it like an overlay and underneath is a long row of lights and things

 

There are lights in a line like this . . . . . . . and they go on/off/flash at a predetermined distance based on the route. Then they put the correct map for the route that is set in the computer.

[Aqueduct]

The last couple of times I've been on the it keeps saying that computerized map that the stops at 51st and Lexington.

[Zman]

I understand now. Is this a daily thing where drivers or conductors reset the train, or is it an uncommon, but not rare thing. Plus, how long does it take to reset the train? If it's a few minutes, then drivers could easily set it while sitting at the station waiting for the terminals to empty out.

 

 

It's uncommon, takes about 1½-2 minutes to reset, and always occurs en route.

[lilbluefoxie]

There are lights in a line like this . . . . . . . and they go on/off/flash at a predetermined distance based on the route. Then they put the correct map for the route that is set in the computer.

 

Its interesing I wonder if somewhere in the yards theres panels for and

[R62A 1991]

Its interesing I wonder if somewhere in the yards theres panels for and

 

That would be interesting if there are. I doubt it, BUT, the lights do work in accordance with (at the very least) the .

 

When I came home from Massachusetts (May 31st), the shuttle to New Lots ran R142s. When the program was set up, it started as saying "The next stop is 145th St." The lights on the stripmap lit up as if it were simulating the lights on a stripmap (meaning mainly ones in the middle). When the C/R changed it to "The next stop is Sutter-Rutland," 7 lights in a row lit up near the end of the map. I should note that they did not match up with the (4)'s Livonia Avenue stops (meaning that it wasn't the very last 7 lights that lit up).

[RokuSix]

Thanks for explaining it, Julio. But you're right, it's not foolproof. I'd say it works around 75 percent of the time.