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Old 05-27-2016, 01:14 PM   #111
xoxoxoBruce
The future is unwritten
 
Join Date: Oct 2002
Posts: 71,105
Oh that's great, and of course mandatory transponders, especially for the children, won't somebody think of the children? You sure as fuck will when you're tied up in traffic because some kid(s) are playing fucking games. Ever watch a kid keep pushing the pedestrian button, like for an hour? And if the little bastard approaches the curb all the cars stop? How far from the curb? From which direction? Jr on a dead run down an alley or side street can run out into traffic in how many nanoseconds? Oh, and the cars will stop in zero feet? Science, bitches.

You're utopia where anyone can just walk out in the street without fear, will be a fucking nightmare. There is only one way to keep people from getting hit by vehicles, and that's to eliminate one or the other. Building utopia in any existing city is not possible. And don't give me crap about this or that city did this or that to make downtown more "pedestrian friendly". Oh, they closed off two of seven thousand streets, isn't that cute.

Quote:
Reaction Distance
One such factor is the perception of an impending danger. The driver of a passenger vehicle usually takes 1.5 seconds to perceive a dangerous situation and apply the brakes. This time is about the same for the average truck driver.

Weight
Another factor that impacts the time it takes for the vehicle to stop is the weight of the vehicle. Even though semi trucks have larger brakes than other vehicles, it usually takes the semi truck much longer to stop because of the much larger weight of the semi truck. Cars have an average weight of 5,000 pounds while a semi truck can weigh up to 80,000 pounds.

Therefore, a car takes about 124 feet to come to a stop when traveling at 40 miles per hour from the time that the driver perceives the danger. In comparison, a truck driver takes approximately 169 feet from the danger perception time when traveling at the same speed.

Speed
A critical component of calculating stop times is to know the speed that the vehicle was traveling right before the accident. The faster the vehicle is traveling, the longer it will take to come to a complete stop. In comparison to the figures noted above, a passenger vehicle will take about 316 feet from the awareness point when traveling 65 miles per hour. The semi truck takes about 525 feet before coming to a complete stop.
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So with your magic braking system cutting the 1.5 seconds reaction time to near zero(which I doubt unless your brakes are going to lock up the moment it senses there might be a danger), at 65 mph you start stopping 140ish feet sooner. It still takes 316/525 feet to stop, IF it's perfect traction, perfect mechanical condition, and the acquired target isn't too smart.

Some truck driver jerking off on a smartphone? It doesn't matter what speed he's going. No technology will make that fool safe on the road.
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