Tag Archives: signals

“Rapid Bus Isn’t as Rapid as Everyone Hoped” – Voice of San Diego

The new Mid-City Rapid isn’t much faster or more dependable than the regular bus it replaced, leaving the El Cajon Boulevard community grasping for the transportation solution it was promised, even while it undergoes a development boom.

Source: Rapid Bus Isnt as Rapid as Everyone Hoped – Voice of San Diego

The article makes it seem like this particular bus line is a failure.  The more I read about it, though, the more it seems like it’s less a failure than a project that oversold its benefits.  And despite the cost, seems to have been cheaped out at some point.

It’s surely not BRT and near as I can tell doesn’t even have rudimentary things like off-board fare collection.  MTS claims that the vehicles  “were designed to streamline and accelerate the boarding process and feature multiple doors, low-floor designs and larger windows” but multiple-door boarding is not the same has having multiple doors.  Sheesh.  A lot of money was spent on the half-dozen or so Rapid routes and even their operation was contracted out to Veolia I suppose to make it seem different (and surely to bust the ATU).  A lot is still left to be desired, though; like the total absence of exclusive lanes.  They do, at least, have signal pre-emption and next-bus signs at stops.

BUT …  ridership on the route is up 18% since the service replaced the former 15 route in October, 2014.  No definitive word, but likely reasons for the increase are that SDSU students trying to get to or from downtown San Diego are saving time, that the route has a long span of service (>20 hours/day), and it has excellent peak/off-peak/late headways (10/15/30 minutes).

Implying that this route is somehow a failure misses the mark.  Less than what was promised?  Yes.  Could things be made better?  Absolutely.  Do we want to look closely at whether it was worth the cost?  Yeah, probably not.  But please, credit where some credit is due.



“4 Reasons to Remove Traffic Lights in the Era of Peak Driving”

Lights are on, but no one is driving home.

4 Reasons to Remove Traffic Lights in the Era of Peak Driving – CityLab.

All surely valid data … but it’s Detroit.  The one in Michigan.  The one that has lost 60-ish percent of its population in the last 60-ish years.  Removing signals there is a great idea.  Selling the recovered equipment will surely more than pay for the new stop signs they’ll need.  At some point they’ll need to consider closing and depaving streets – they just aren’t needed.

But did I mention this is Detroit?  I’m not sure what relevance this study has to any other city.  At least cities not named Cleveland, Buffalo, or Youngstown.  The authors make the point that vehicle-miles traveled have leveled off nationwide after growing every single year since the end of the Second World War and that this may be a guide.  Yes, it may be but in the developed part of the country (i.e. not Detroit) VMT has leveled but it’s not dropping.

“Justice” (Season 1, Episode 8): “A System to Cut City Traffic That Just Might Work”

Article: A System to Cut City Traffic That Just Might Work | WIRED.

I like the idea of the token system.  This is not unlike token signaling systems used on British railways on single track branches – if you have the token, you can enter the branch.  The difference here (aside from it being cars, not trains) is that there is more than one token.

At first glance, I like the idea of limiting the number of cars in the congested area, rather than just charging a fee to anyone that comes in.  The challenge, though, is that you’d need to know how many tokens is the “right” number; a non-trivial exercise.  With a congestion charge, there isn’t a hard limit to the number of vehicles because you rely on prices to discourage vehicles from entering the zone.   If you set the prices appropriately, and that has to include a rise in price as more vehicles enter the zone, then it should be OK.  If you set the price too low, however, then more and more vehicles will enter the congestion zone.  You’d have the same congestion and a bunch of revenue.

The thing I don’t like about this method is the idea that you can change the congested area on the fly.  How does this work?  If you’re in a zone that was just designated as “congested” by the controller, do you have the chance to move out of it?  How would you even know?

This is not unlike the Star Trek: The Next Generation episode “Justice” (Season 1, Episode 8), where there are random “punishment zones”.   Anyone caught in them is, of course, put to death (because Star Trek).  Guess where Wesley Crusher ends up?

Though the penalty is less harsh here, I don’t see the “moving zone” working out very well.  Different areas on different days?  Sure.  But no changes during the day.

People are stupid: “Traffic Light Study Reveals Serious Hacking”


Article: Traffic Light Study Reveals Serious Hacking Risk | MIT Technology Review.

“First and foremost, traffic-system administrators should not use default usernames and passwords.”

Unlike traffic signals in my local area, which are networked with fiber (!), these were networked over WiFi.  If details — 5.8 GHz — in a different article are to be  believed, then this is either IEEE 802.11a or 802.11n which are common consumer WiFi specs.

Encrypted or not, leaving credentials at the default is stupid.  In the field of traffic signaling, it probably ought to be a firing offense.  Anyway, change those and risk would be reduced by, oh, let’s say 99%.

Another quote:

“They continue doing the same mistakes that software vendors did 10 years ago.”

No, that’s been going on for a long time. The default credentials for Digital’s VMS OS were SYSMAINT / SERVICE and that’s got to be from 30 years ago.

If you leave the doors unlocked and open, people will walk through them