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Comment: Re:What's wrong with American drivers? (Score 1) 171

by NormalVisual (#47961185) Attached to: Washington DC To Return To Automatic Metro Trains
Yes, they are quite light. We have six-car trains with a capacity of 60 passengers per car, so the capacity is comparable, but they've got composite bodies over a steel subframe, which saves a lot of weight. They don't have to be really heavy since it's an elevated system with no chance of interaction with roadway traffic, and owing to their configuration, they deal with high winds quite well without needing the extra weight just to keep them on the track. Additionally, there are some grades on the system (around 9%) that would bring any traditional rail prime mover to a screeching halt, plus the trains have to be able to take those grades at speed (and sometimes accelerate) with only half the motors if needed. Top speed on our trains is electronically limited to 40mph, but to my knowledge they're physically capable of running well in excess of 60mph.

Comment: Re:What's wrong with American drivers? (Score 1) 171

by NormalVisual (#47958499) Attached to: Washington DC To Return To Automatic Metro Trains
Don't we have machine learning and adaptive control for that? These things should still be easier for a computer than for a human.

I'm not disagreeing with you. I didn't design the train control system. :-) There was so much on our trains that the drivers really shouldn't have had to deal with, and I found it kind of ironic that the Orlando International Airport terminal shuttles had more smarts than our trains. As of 2012, Disney had concrete plans in place to finally put automation on the trains, which I personally think is going to be a losing proposition on a fleet of 25 year old monorails with 1970's-era control systems (the vehicle on-board controller is run by a pair of Z-80s) and millions of miles on them, and at their age are already *very* maintenance intensive. They get tons of PM, but nowadays it's unusual for a day to go by without at least one train having to go back to the shop, and not a week goes by where one doesn't get towed.

Comment: Re:What's wrong with American drivers? (Score 1) 171

by NormalVisual (#47957453) Attached to: Washington DC To Return To Automatic Metro Trains
but often gets the calculation wrong because even though the system "knows" how much each car weighs, people sway back and forth as the vehicles slow down and we undershoot the platform.

That's good that it's conservative like that, but does it actually bring it to a complete stop short of the mark? There have been times when I've been driving a full train that it slowed a bit more aggressively than I would have expected, but it was easy to just modulate the brakes to hit the mark without stopping short. Then again, our trains were substantially lighter (about 50 tons empty, 80 tons crush load), so I'm sure it was easier for us to deal with the varying inertia.

Comment: Re: What's wrong with American drivers? (Score 2) 171

by NormalVisual (#47957271) Attached to: Washington DC To Return To Automatic Metro Trains
I would hope that any company developing systems to automate control of any vehicles, most of all those tasked with mass transit automation, are fully aware of the need for redundant feedback systems which provide inegrated positioning and acceleration sensors built into every smart phone today.

Our trains had a pair of tachometers that measured speed, along with fixed transponders every thousand feet or so along the beamway. Between the tachs and the transponders, the train could figure out where it was and how fast it was going to quite a good degree of accuracy. When the tachs disagreed with one another or if a transponder was missed we'd get an indication, even though the train still knew exactly where it was. I'm sure integrating the tach inputs over time to get an acceleration value would be relatively trivial.

Comment: Re:What's wrong with American drivers? (Score 3, Interesting) 171

by NormalVisual (#47956903) Attached to: Washington DC To Return To Automatic Metro Trains
Disney's trains were retrofitted in the mid/late 00's with a similar system. There are three optical switches that all have to be aligned with corresponding places at the station, otherwise the driver is unable to open the doors. It was fairly easy to only get one or two of the sensors in place, requiring the driver to move the train a couple of inches forward or back to get his doors open. It's gotten to be a real headache for today's drivers, since the new rules Disney instituted after the accident in 2009 require that *any* reverse motion of the train be set up by the central coordinator and visually cleared by an independent spotter beforehand, even if it's only to back up an inch.

Comment: Re:What's wrong with American drivers? (Score 5, Informative) 171

by NormalVisual (#47956323) Attached to: Washington DC To Return To Automatic Metro Trains
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.

I have a perspective on this that most probably don't, as I was a monorail driver at Disney World for a number of years. Contrary to what some might imagine, the current Bombardier Mark VI trains there are not attractions but are in fact full-up transit vehicles, and Bombardier continues to sell them as such (although with different bodies and newer electronics). If D.C.'s trains handle anything like ours did, I can understand why some of the drivers short-stop or otherwise have problems.

Our Mark VI trains were originally designed to accommodate automation as well, but I don't think this in itself really is a factor. More importantly, each train had its own "personality" and handled differently, and all of them would take between one and two seconds to respond after an input was commanded except for E-stops, which instantly opened the relay contactors and applied air to the friction brakes. One train might be ultra-responsive (relatively) to the throttle and have really tight brakes, which made it easy to drive and predict stopping distances with great accuracy. Others would act like your control inputs were more of a suggestion than a command, necessitating that you be looking a little ahead of where you actually wanted to be in order to stop where you were supposed to. We had some drivers that had difficulty dealing with that, and would often blow their stops by a couple of feet or so on a train with loose brakes, or would stop short if they were in a tighter train that didn't require so much anticipation of its behavior. I don't think I ever had a short stop, but did have trains "slide" on me a few times and missed the stop by just enough to have to back up a couple of inches to get lined up with the gates.

I would imagine transit trains everywhere exhibit similar unique peculiarities, and the only consistent way to deal with it is for the driver to be ultra-conservative, which can lead to the occasional short stop. It's not so much a problem for an automation system that can directly respond in milliseconds and isn't being moved between trains with wildly varying performance characteristics.

Comment: Re:Virtual Desktops (Workspaces) (Score 3, Interesting) 541

by NormalVisual (#47923239) Attached to: What To Expect With Windows 9
I understand what you're saying (I think) but I've always wondered (and this is from a hardware-guy's perspective) wouldn't you rather have one big monitor [], than two small monitors []?

I actually prefer multiple displays along with virtual desktops, as the bezel doesn't bother me, and it's easier for me to have a dev environment on one screen with documentation/tools on the other sans taskbar, with the virtual desktops being used for stuff like IMs, email, etc.. Maximizing something on the second display fills that display, but leaves the primary untouched. Additionally, there are some folks that prefer to use multiple displays in different orientations, although I'm not one of those. Finally, it's cheaper. :-) Having said that, it's not something I'm dogmatic about. People should use whatever works best for them.

Comment: Re:Paint job, or just looked different on TV? (Score 1) 99

by NormalVisual (#47905709) Attached to: Original 11' <em>Star Trek Enterprise</em> Model Being Restored Again
Of course it doesn't look like it appeared on TV, but when he did the restoration, Ed left the top portion of the saucer as it was originally done, minus touch-ups to hide where repairs had been made. Comparing the top and bottom of the saucer, it's obvious that while the original paint scheme did have very faint grid lines and weathering, it wasn't airbrushed to the extent of being overbearing like he did to the lower saucer and most of the rest of the model. He also added details to the model that were not present originally.

Comment: Re:Crude? (Score 1) 99

by NormalVisual (#47904495) Attached to: Original 11' <em>Star Trek Enterprise</em> Model Being Restored Again
Bingo. I bet the one-off single-show models were done as well as required- and no more.

The ones I was referring to specifically were props like phasers, tricorders, etc. that were used throughout the production run, but as you say, no studio wants to spend more money than absolutely necessary. If the prop guys can hack out 10 phasers in a day that will look acceptably on screen, instead of spending a day on each one making them museum-quality, it's not hard to figure out which route the studio will choose.

This is part of why I was so impressed with the Star Wars miniatures. There's detail there that's too fine to show up on even on 4K, and I really respect the obvious pride and effort that went into them.

Comment: Re:Crude? (Score 2, Interesting) 99

by NormalVisual (#47903793) Attached to: Original 11' <em>Star Trek Enterprise</em> Model Being Restored Again
Models built for TV in years past often weren't built with much detail, simply because it wouldn't show up on screen anyway. That said, the TOS Enterprise did have a lot more detail than one would expect for a TV show (there are markings and such that are too tiny to see on TV), but it pales when compared to the Enterprise built for "The Motion Picture" which has much, much finer detail. A couple of years ago I had the opportunity to see a lot of the Star Wars filming miniatures - the Millenium Falcon hero model built for "The Empire Strikes Back" was just jaw-droppingly gorgeous, and holds up to inspection from just inches away. Compare that to some of the ST:TNG props that I've seen that look fine on screen, but when examined closely look like someone gave a 5-year old a couple of shots of vodka and turned them loose with a paintbrush.

If you have to ask how much it is, you can't afford it.