BTW it gets even more exciting (or complex) when you add Overlap Phases (used in the older 5 section with the protected permissive setup Let the confusion begin ;-) Phase 1 (Green Left Arrow N/B S/B) Then S/B no longer has a car in the turn lane so it ends (Yellow Arrow then off). N/B still has cars in the turn lane and N/B Thru will get an Overlap A Green ball (and N/B pedestrian). S/B is all red. N/B left turn finally ends, and S/B moves on to Phase 2 thru times with Overlap A and Phase 2 peds (if applicable). There are 4 Overlap functions engineers can choose from A,B,C,D in an 8 phase intersection. Again this is the old school 5 section traffic lights. In modern times the green ball has been removed and you have a 4 (or sometimes 3) section signal where the lower yellow arrow is flashing) Using the lead/lag formula (thru traffic times before turning traffic), California Right Turn (usually times N/B or S/B right turn with E/B or W/B left turn usually NO RIGHT TURN ON RED signs are posted where this is used in some cases) Odd Phase (left/right turn movement Phases 1,3, 5, 7) pedestrian movements where N/B left side peds are WALK and S/B Left arrow is active. Not a conflict. Finally the newest variant of flashing left/right permissive yellow arrow turning. BTW all of these would be outstanding "How It Works" videos. Yes your brain will hurt, but I know many of you have seen these movements in action. :-)
Adrian I too have been into traffic lights since I was a kid. I love collecting the old ones from the 70s and 80s (my generation) and the old NEMA controllers from those eras. If you really want to dive into this field, go to www.imsasafety.org/ They have the books on becoming a traffic signal tech, and where you can take the official classes for certification.
In chorus with these other comments, I love your videos too! I finally got in contact with my own cities signal superintendent so I may be getting an opportunity for a in-person demonstration. Would recommend contacting yours to any other people with the same interest.
One of the more interesting things in traffic signaling is the terminology. The term Phase for example means something completely different in electrical engineering. Why traffic engineers chose "phase" to to refer to a particular direction of traffic lights is beyond me. For the sake of confusion a different word should have been chosen. :-)
really good video, I have a question though, I'm currently working on a thesis about traffic light systems, and I have no idea about this subject since my main studies are computer science, so my task is to conceive a traffic light system in an intersection or at least do a simulation about it (in unity), does anyone know some useful resources about this subject, especially if there are available solutions online for this problem so I can look up to(software and hardware, system, how they manage it, etc..)
I am so sorry that it took so long for me to get back here and reply to you. Hopefully you found the information necessary to write a well-informed thesis and you won a Nobel prize for it. Or at least a passing grade.. what I could tell you is that different municipalities deal with different vendors that usually sell them on products and systems for their control systems. Depending on the manufacturer there are different remote monitoring and control applications that are used remotely typically from a command location. Here at my municipality we use econolite equipment, and the software for remote monitoring the signals that are networked is called Centracs. All of the timing, coordination, time of day plans, flash status, detection, everything in relation to the operation of the signal for the most part is observable from the command center where the software is installed. Our engineering department has a good handful of traffic engineers that monitor the equipment remotely and will consult with us for timing adjustments in the field and sometimes we will call them to make remote adjustments when we receive complaints. On top of this we also have some surveillance cameras around different corridors that allow for us to observe the operation of signals remotely to fine-tune adjustments when there are repeat traffic issues for a specific movement. All of these things for the most part require some sort of interconnected communication between all of the signal cabinets and a connection to the network that leads to our operations center. We use different networking equipment at different locations some are on private cable with firewalls installed for them to get into our network through a virtual private connection, some are on fiber optic cable that runs directly into our buildings and directly onto our network. There are also signals where we have old copper interconnect that is being used now with technology called ethernet over copper that allows a high-speed connection over old lines that were used for modem and telephone use. We also have some signals that are remote and unconnected from anything else but due to the requirement that we have something to monitor in that cabinet we will install a cellular gateway that provides an internet connection through a SIM card of a cellular provider and an ethernet port to connect directly to the switch that the cabinet equipment is plugged into. These units must be configured specifically to have a static IP which means the IP address never changes. All of these different interconnected systems are more recent developments over the past 20 or so years with networking traffic signals, however some of our signals were actually networked as early as the 1980s with twisted pair copper and monitronics monitoring systems. These systems were modem-based and required a lot more time to transfer information throughout the day but we're still very effective in keeping the clocks set correctly as well as providing early warning of signal issues.. Hopefully this information has proved useful and you are now an engineering wizard.
What I don't get is, phase just seems to indicate or relate to traffic direction, but what I don't understand is when a light is green yellow or red, that timing. Do the controllers control that switching and in a timing plan one only specifies how long and when a phase runs IE is in green, or when each individual red green yellow light is lit and when? Does a phase equate physically to a single signal that consists of a red yellow green? Do the controllers automatically figure out the red yellow green switching or is that also a part of the timing plan? This is just not clicking for me yet. I just took a quick class on iteris and the class all assumed everyone knew about phases and timings, well I'm an IT guy hehe.
If you're referring to Gap as passage time that might be a pretty good video for me to make. Passage time turns out to be relatively useful for adjusting how cars actuate the signal and allowing for more cars to actuate the signal based upon the available detection methods. I have come to find that typically a gap of 2 seconds is adequate for an average traffic signal with both detection at the stop bar of the intersection as well as perhaps advanced detection depending on the speed of approach.
There's always a grumpy thumbs downer... That's cool, I can't please everyone. Some folks are just mad at me because they think I'm the one that makes their commute harder.
BTW it gets even more exciting (or complex) when you add Overlap Phases (used in the older 5 section with the protected permissive setup
Let the confusion begin ;-)
Phase 1 (Green Left Arrow N/B S/B) Then S/B no longer has a car in the turn lane so it ends (Yellow Arrow then off). N/B still has cars in the turn lane and N/B Thru will get an Overlap A Green ball (and N/B pedestrian). S/B is all red. N/B left turn finally ends, and S/B moves on to
Phase 2 thru times with Overlap A and Phase 2 peds (if applicable).
There are 4 Overlap functions engineers can choose from A,B,C,D in an 8 phase intersection. Again this is the old school 5 section traffic lights. In modern times the green ball has been removed and you have a 4 (or sometimes 3) section signal where the lower yellow arrow is flashing)
Using the lead/lag formula (thru traffic times before turning traffic), California Right Turn (usually times N/B or S/B right turn with E/B or W/B left turn usually NO RIGHT TURN ON RED signs are posted where this is used in some cases)
Odd Phase (left/right turn movement Phases 1,3, 5, 7) pedestrian movements where N/B left side peds are WALK and S/B Left arrow is active. Not a conflict.
Finally the newest variant of flashing left/right permissive yellow arrow turning. BTW all of these would be outstanding "How It Works" videos.
Yes your brain will hurt, but I know many of you have seen these movements in action. :-)
You make a great teacher 💯
Make sure to make more videos
Awww schucks! Thank you!
Mannn. Keep these videos going. They are very helpful to noobs like me. Ty for your knowledge 👌
No sweat homeslice!
I've been liking traffic signals since I was a kid so I'm sure that others would learn if they're interested
Awesome!
Adrian I too have been into traffic lights since I was a kid. I love collecting the old ones from the 70s and 80s (my generation) and the old NEMA controllers from those eras. If you really want to dive into this field, go to www.imsasafety.org/ They have the books on becoming a traffic signal tech, and where you can take the official classes for certification.
Hi liked the video, helped me out a lot. Can you do a video on pedestrian “walk, don’t walk” phasing and push button phasing? Thanks
Okay 👌
Great explanation, thank you
Would you be interested in creating and explaining a TSD time space diagram base on existing timing sheet for an intersection? Thank you
In chorus with these other comments, I love your videos too! I finally got in contact with my own cities signal superintendent so I may be getting an opportunity for a in-person demonstration. Would recommend contacting yours to any other people with the same interest.
Thank You!
City, County and State municipalities would likely be thrilled to show you their stuff.
💯💯 💯💯 💯
Thank you.
Thank you sir 🙏🏻
One of the more interesting things in traffic signaling is the terminology. The term Phase for example means something completely different in electrical engineering. Why traffic engineers chose "phase" to to refer to a particular direction of traffic lights is beyond me. For the sake of confusion a different word should have been chosen. :-)
Can you do a video on how to read Traffic signal Plans?? Would be great
Check the new video! :)
@@trafficsignalstraining7673 Thank you ! Was really hoping you’d see this !
really good video, I have a question though, I'm currently working on a thesis about traffic light systems,
and I have no idea about this subject since my main studies are computer science, so my task is to conceive a traffic light system in an intersection or at least do a simulation about it (in unity),
does anyone know some useful resources about this subject, especially if there are available solutions online for this problem so I can look up to(software and hardware, system, how they manage it, etc..)
I am so sorry that it took so long for me to get back here and reply to you. Hopefully you found the information necessary to write a well-informed thesis and you won a Nobel prize for it.
Or at least a passing grade.. what I could tell you is that different municipalities deal with different vendors that usually sell them on products and systems for their control systems. Depending on the manufacturer there are different remote monitoring and control applications that are used remotely typically from a command location.
Here at my municipality we use econolite equipment, and the software for remote monitoring the signals that are networked is called Centracs. All of the timing, coordination, time of day plans, flash status, detection, everything in relation to the operation of the signal for the most part is observable from the command center where the software is installed.
Our engineering department has a good handful of traffic engineers that monitor the equipment remotely and will consult with us for timing adjustments in the field and sometimes we will call them to make remote adjustments when we receive complaints.
On top of this we also have some surveillance cameras around different corridors that allow for us to observe the operation of signals remotely to fine-tune adjustments when there are repeat traffic issues for a specific movement.
All of these things for the most part require some sort of interconnected communication between all of the signal cabinets and a connection to the network that leads to our operations center.
We use different networking equipment at different locations some are on private cable with firewalls installed for them to get into our network through a virtual private connection, some are on fiber optic cable that runs directly into our buildings and directly onto our network. There are also signals where we have old copper interconnect that is being used now with technology called ethernet over copper that allows a high-speed connection over old lines that were used for modem and telephone use. We also have some signals that are remote and unconnected from anything else but due to the requirement that we have something to monitor in that cabinet we will install a cellular gateway that provides an internet connection through a SIM card of a cellular provider and an ethernet port to connect directly to the switch that the cabinet equipment is plugged into. These units must be configured specifically to have a static IP which means the IP address never changes.
All of these different interconnected systems are more recent developments over the past 20 or so years with networking traffic signals, however some of our signals were actually networked as early as the 1980s with twisted pair copper and monitronics monitoring systems. These systems were modem-based and required a lot more time to transfer information throughout the day but we're still very effective in keeping the clocks set correctly as well as providing early warning of signal issues..
Hopefully this information has proved useful and you are now an engineering wizard.
Nice work
What I don't get is, phase just seems to indicate or relate to traffic direction, but what I don't understand is when a light is green yellow or red, that timing. Do the controllers control that switching and in a timing plan one only specifies how long and when a phase runs IE is in green, or when each individual red green yellow light is lit and when? Does a phase equate physically to a single signal that consists of a red yellow green? Do the controllers automatically figure out the red yellow green switching or is that also a part of the timing plan?
This is just not clicking for me yet. I just took a quick class on iteris and the class all assumed everyone knew about phases and timings, well I'm an IT guy hehe.
Thanks
Great vid this is the second vid I check from your channel, Could you please make a video based on Gap reduction for traffic signal timing. Thank you
If you're referring to Gap as passage time that might be a pretty good video for me to make. Passage time turns out to be relatively useful for adjusting how cars actuate the signal and allowing for more cars to actuate the signal based upon the available detection methods.
I have come to find that typically a gap of 2 seconds is adequate for an average traffic signal with both detection at the stop bar of the intersection as well as perhaps advanced detection depending on the speed of approach.
i like this guy
I can't believe someone gave this a thumbs down 🤔
There's always a grumpy thumbs downer... That's cool, I can't please everyone. Some folks are just mad at me because they think I'm the one that makes their commute harder.
Do you take video requests?