Got Caught By a Red Light Camera?

2oldman wrote:
I've gotten a ticket for a rolling stop at a right-on-red in Wenatchee WA. I was guilty so I paid it.

valhalla360 wrote:
The more important issue is are the speed limits and signal timings set correctly.I'm a traffic engineer and set both (I haven't done cameras as the states I typicaly work in don't allow them).

A little off topic, but I thought you might have an opinion on this:

Traffic lights are the great guessing game of driving, and they shouldn't be. The worst case is on freeways with lights, like in Southern CA on the 86 freeway. And those stupid flashing amber lights a few hundred feet ahead of the signal..? ..worthless because they flash ALL the time. One only has to look down at the skid marks on the pavement to know how dangerous it is.

What would be the feasibility of having wifi devices in signal boxes to tell drivers with receivers how long that green is going to be? It would be a huge help to truckers, and those of us who tow heavy rigs. I doubt the amber is timed to how long it takes a big rig to stop.

95% of advance signal ahead flashers are a waste of money and more importantly, they undermine thier value in the 5% of locations where they are of benefit.

As far as advance notice devices, a few thoughts:

The assumed deceleration rate is typically assumed to be 10ft/sec2. If your vehicle can't slow that quickly, you have a brake problem...and there is a perception reaction time built into the formula. Even trucks and RV's should be able to double that deceleration rate without it being a panick stop. So, the need for more braking distance for large vehicles is already accounted for. See the link below for a detailed explaination of the method used in Michigan(page 26 & most other areas follow a similar approach).

You can set up the flasher to come on just before the signal is about to change but in most cases, this results in drivers speeding up. We use these occassionaly but usually where there is limited visibility at a signal (ie: a sharp turn and then you are on top of the signal) The new systems (discussed below) will have to sort thru this issue anew.

As far as wifi, no it won't be wifi. The near future is Vehicle to Infrastructure (V2I) using DSRC radios feeding SPaT data. It's an independent radio system with dedicated bandwidth set aside for transporation systems. One of the functions (among many) is SPaT (Signal Phase and Timing). An output for the signal controller is sent via radio. Included is a geographic map of the intersection including all lanes, what movements are allowed in each lane and which signal phases are associated with those lanes. The second part is the timing data, what is sent out is the current status of each phase, the next status for that phase and how long before the change. With adaptive systems, this is more challenging than you might think, since the controller often doesn't know what phase will be on in 15 seconds (there is a solution but it gets a little complicated). Now once the car recives the data, there is a high definition GPS that can determine which lane the car is in along with it's speed and direction. At that point, the onboard system can calculate when the car will arrive. The way it's set up now, it's just data sent out. Manufacturers both original and after market will take the data and develop applications. That can vary from a buzzer or light that goes off if you are in danger of running a red light to ultimately hitting the brakes for you. (This is also tied to V2V systems on the same radio network where the cars around you tell your car where they are and what they are doing). I believe Cadilac is the first company to announce they will be offering an OEM system using it in late 2015.

http://mdotcf.state.mi.us/public/tands/Details_Web/mdot_signal_optimization_guidelines.pdf