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5 votes

What kind of splines should be used when planning roads?

Roads are usually designed using catenary curves. https://sketchup.engineeringtoolbox.com/catenery-curve-c_169.html Road curves are designed around vehicle velocities and they are not uniform. As ...
Rhodie's user avatar
  • 982
5 votes

What kind of splines should be used when planning roads?

Circular arcs are not used except in special situations, because the sudden change in curvature from a straight road to a circular arc would mean drivers had to quickly turn the steering wheel to the ...
alephzero's user avatar
  • 12.6k
3 votes

What is the starting/stopping sequence of a traffic light

What country? This is different between different countries. I can give the sequence in Poland, which is standard in most of EU. 180 seconds of Blinking Yellow. (Groups [**] with Yellow blink ...
SF.'s user avatar
  • 6,115
3 votes

How do you call the intersection with barrier and you can always right turn?

In UK terminology, your separate turning lane would be called a "filter lane" ( see e.g. Collins dictionary definition). This definition doesn't mean that you can always turn in that lane, it means ...
AndyT's user avatar
  • 3,143
2 votes

What's the purpose of a 'burger' lane in a roundabout?

Another purpose of such a lane is to allow for vehicles that cannot navigate the roundabout to travel through. For example a tram's turning radius may not allow them to drive around the roundabout so ...
ratchet freak's user avatar
2 votes
Accepted

What's the purpose of a 'burger' lane in a roundabout?

There are several of these near where I live (in the UK) but I've never heard the term "burger lanes" before. We don't seem to have a name for them - they just are! They serve the same basic function ...
alephzero's user avatar
  • 12.6k
2 votes

How do you call the intersection with barrier and you can always right turn?

This is probably an example of a channelized intersection, where you have right turn bays that split from the main road just before the intersection: References: Individual Movement Treatments - ...
gate_engineer's user avatar
1 vote
Accepted

"Burger" lanes: What are they, where are they found, and what do they look like?

if your question is how they look like then: figure: source hulldailymail or figure: source openstreet wiki They are also known as "through roundabouts" As to their name I suppose that ...
NMech's user avatar
  • 24.4k
1 vote

What kind of splines should be used when planning roads?

Clothoid? I recall hearing that some roadway curves are designed using the Clothoid Spiral AKA the Spiral of Cornu AKA https://en.wikipedia.org/wiki/Euler_spiral in which the (radius of) curvature ...
Catalyst's user avatar
  • 161
1 vote

What is the starting/stopping sequence of a traffic light

There is another state the lights can be in: blinking yellow. Which means that the intersection is not being controlled and normal priority rules are in force. Going from off to all blinking does not ...
ratchet freak's user avatar
1 vote

How can traffic signal controllers handle multiple conflicting preemption requests of equal priority without dropping one?

As you might well imagine, there is a metric f-ton (the technical term :-) ) of research covering both queuing theory and prioritization analysis. The correct, if unsatisfying answer to your ...
Carl Witthoft's user avatar
1 vote

Historically, how did tram switches work?

I think you don't understand how the switch can work if there is no place to put the lever in the middle of a street. The answer is simple: you only put the socket and every driver brings his own ...
Agent_L's user avatar
  • 426
1 vote

Historically, how did tram switches work?

I don't see why the simplest explanation isn't the best, i.e. manual switches. Freight trains used to have people on board whose entire job was to manually walk and throw switches. This would work ...
hazzey's user avatar
  • 10.7k

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