Respect for Signal EngineersPosted on June 7, 2010 in AmusingFrom the rather mysterious cartoonist xkcd.com:I’ve certainly met both of these characters many times. Come to think of it, I’ve been both of these characters.Related Posts 2-1 1-1 8
That car is probably waiting at the light at Denver and Interstate in N. Portland… wondering when there will be a gap in MAX trains… 🙂
Dont blame the light, blame the person who decided 7 roads should meet at an intersection, and then blame the person who decided that a stoplight would be able to deal with that effectively.
@Scotty. Since MAX trains are pretty empty by the time they get to Denver/Interstate, I’m sure he’s angry at the transit planners too.
Here’s one that comes close :
San Francisco’s 19th Ave + Winston Dr. (Stonestown Galleria Shopping Center)
What makes this intersection nasty is its conflicting uses (cars, buses, LRVs when running) and age. Basically, it needed to be totally rebuilt a la Geary + Masonic or Geary + Fillmore decades ago. One substantial collision could shut the whole sector down for an hour or more even with traffic being diverted to the arterial (Junipero Serra Blvd.) just to the east.
Here’s one for the “Stacked Lights” file :
Daly City’s John Daly Blvd. (JDB) as it passes the DC BART station and crosses I-280 / CSR-1
I’ve driven east on JDB so that I could turn left onto either CSR-1 or I-280. Picking the correct left turn lane does take some practice. If you don’t turn off JDB and continue east you encounter the lights that control the bus egress and station access.
Kudos to the planners and engineers who have worked hard to keep the traffic flowing through intersections like these.
Signals have come along way in the last decade. You do notice the difference when you are at a set which is out of date.
Signals are more friendly to alternative modes than roundabouts! Thats one other thing drivers struggle with.
In Brisbane, Australia, one set of signals in particular is especially slow for buses exiting the William St portal to cross Victoria Bridge. Here, only 2-3 buses get through at a time, with a minute-and-a-quarter’s wait for the next buses to get through. What would be a more suitable timing pattern for this important part of the busway system? Is it realistic to make the maximum wait for the buses 30 seconds, for instance?
Ahh, I’ve been following this comic religiously for years!
You may also enjoy this one…
…Do engineers spend weeks simulating traffic patterns to come up with signalling that makes all traffic lights on a downtown road change signal in unison?
@ Ant6n: No, we try and get them to spell out our initials when viewed from the eye-in-the-sky traffic helicopter.
In North America, the T is easy – it’s the W that causes issues.
Ha! I love XKCD.
Here in Vancouver, a lot of our traffic signals stay green until a pedestrian or cyclist pushes a button to cross. There is a particular light on a hill on my running route that always takes forever to allow me to cross when I am going downhill, and changes right away when I’m going uphill, denying me the breather!
You need to come to San Francisco then and hack the lights along Market Street. Your “T” would be Market and points south and your “W” would be based on Market with its arms to the north. Rough approximation :
Any cartoons of people who expect that a transit signal priority system will perform well the first week it is in service (without all the trial and error work that went into refining the previous scheme over a period of years)?
Eric: no. Plenty about people who expect that it will work in its fifth year of service, though. They’re called “customers.”