watches running on light image
Q. About a year ago, while driving home with my sister (we we're in different cars) I watched a semi-truck run a red light and kill her. I can't stop replaying it in my head. Does hypnosis work? Or therapy? I'll basically try anything.
Answer
Yes, hypnosis and therapy, will help, maybe some pills also
Yes, hypnosis and therapy, will help, maybe some pills also
How can I contest a red-light camera citation I recieved in the mail?
Balk
So i just got one of those citations in the mail and I started looking around on the internet. I live in Springfield, MO and Springfield lowered the yellow light times just before they installed the red light cameras to increase revenue. I watched the video and i went through the light at like .73 seconds after it had turned red. I think it would have been unsafe to stop at the 40mph intersection and the other guy next to me in the video ran the light too. Any suggestions on how to contest this thing?
Answer
I hate to tell you this, but those cameras are only set up to catch you if you cross the stop line after the light turns red. Which you are basically admitting you did.
Also as a traffic engineer who knows the ins and outs of how the cameras are set up as well as how signal timings work, I can tell you there is little chance that the City lowered the yellow timings to try to raise more revenue. Lowering the yellow and all red time on the signal could cause an unsafe condition and if someone was in an accident at any of these intersections after the City changed the timings they would be in for a serious lawsuit. I don't think any City is foolish enough to do that just to raise some money. They are going to catch enough violaters whatever the yellow times are.
That being said, the yellow time should be set up so that if you are traveling at 40mph like you are supposed to be, and you cross the detection area the signal will stay green if the timing of the signal hasn't reached it's maximum. If it has the light will turn yellow, but should be programmed to stay yellow long enough for you to decelerate including your reaction time to a stop before reaching the signal. The equation for calculating phase-change intervals for a signal is:
CP = t + (V/(2a+64.4g)) + ((W+L)/V)
CP = total phase change period in seconds (yellow and red time)
t = reaction time (usually assumed to be 1.0 second)
V = approach speed in ft/sec
a = deceleration rate ( Usually 10ft/sec/sec)
W = Width of the intersection you are crossing
L = Length of vehicle (Usually assumed to be 20 ft.)
g = grade of the approach lane
Assuming you can gather all of this information, you could calculate the time the light should be yellow and all red. The yellow clearance is usually the first two terms of this equation and the red time is the final part. This assumes that if you did enter the intersection just as the light tuned red, that you would be able to cross it before the other light turned green.
Assuming the intersection is relatively flat the yellow time should be about 3.5 sec.
I hate to tell you this, but those cameras are only set up to catch you if you cross the stop line after the light turns red. Which you are basically admitting you did.
Also as a traffic engineer who knows the ins and outs of how the cameras are set up as well as how signal timings work, I can tell you there is little chance that the City lowered the yellow timings to try to raise more revenue. Lowering the yellow and all red time on the signal could cause an unsafe condition and if someone was in an accident at any of these intersections after the City changed the timings they would be in for a serious lawsuit. I don't think any City is foolish enough to do that just to raise some money. They are going to catch enough violaters whatever the yellow times are.
That being said, the yellow time should be set up so that if you are traveling at 40mph like you are supposed to be, and you cross the detection area the signal will stay green if the timing of the signal hasn't reached it's maximum. If it has the light will turn yellow, but should be programmed to stay yellow long enough for you to decelerate including your reaction time to a stop before reaching the signal. The equation for calculating phase-change intervals for a signal is:
CP = t + (V/(2a+64.4g)) + ((W+L)/V)
CP = total phase change period in seconds (yellow and red time)
t = reaction time (usually assumed to be 1.0 second)
V = approach speed in ft/sec
a = deceleration rate ( Usually 10ft/sec/sec)
W = Width of the intersection you are crossing
L = Length of vehicle (Usually assumed to be 20 ft.)
g = grade of the approach lane
Assuming you can gather all of this information, you could calculate the time the light should be yellow and all red. The yellow clearance is usually the first two terms of this equation and the red time is the final part. This assumes that if you did enter the intersection just as the light tuned red, that you would be able to cross it before the other light turned green.
Assuming the intersection is relatively flat the yellow time should be about 3.5 sec.
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