Countdown Signal Heads For Vehicles

1
Countdown Signal Heads For Vehicles
2
Outlines

• Problem Statement
• Hypothesis
• What are the benefits of the countdown timer?
• How would the countdown timer enhance safety ?
• Possible Implementations
• Two types of Countdown Timer Signals
• Comparing the two types of the Countdown Timers
• Discussion
• Would this encourage drivers to speed up and
  cause even more accidents?
• Day time and night time
• Other issues..

3
Problem Statement

• Crash analysis show that a high percentage of
  crashes, injuries and fatalities for Drivers,
  Cyclist and Pedestrians occur at busy traffic
  intersections specially the Rear End and Angle
  type crashes.
• Example US 440 _at_ Wake Forest Road. 325 Crashes
  for the past three years , 118 crashes is Rear
  End, and 84 is Angle type.
• The percentage of rear end and angle crashes for
  Wake County for the past three years is 35.42
  and 14.36 respectively.

4
Problem Statement

• The hesitation that every one of us experience,
  whenever we approach an intersection while the
  yellow light is on, is a major factor in these
  fatal collisions. (Should I pass or stop?)

5
Hypothesis

• Countdown signals for vehicles would
• Enhance safety at high risk intersections by
  reducing angle and rear end type crashes.
• Studies show that pedestrian countdown signals
  enhanced safety at crosswalks.
• Reduce the amount of lost time for each cycle by
  reducing the all-red time, and therefore increase
  capacity.

6
How does the Countdown Timerenhances safety?

• Countdown signals would provide visual
  information and guidance to drivers regarding the
  amount of time remaining to safely cross an
  intersection.
• Attracts drivers attention to the yellow light
  by visualizing, rather than guessing, how many
  seconds left for them to slow down and stop
  safely before the red light turns on.
• Caution aggressive drivers while approaching an
  intersection to slow down when they see a timer
  instead of a solid yellow light. That would
  reduce red light runner drivers.

7
Two Types of Countdown Signals

• Countdown signal head as a separate unit.
• Countdown timer inside the yellow circular ball.

8
First Proposed Implementation
2
4
1
0
3

• Countdown signal head as a separate unit.
• Installed as a rectangular screen that can
  display big enough digital numbers.
• It works along with the yellow light interval.
• This can cost around 1000 plus maintenance.

9
Second Proposed Implementation

• Countdown signal timer will display digital
  yellow color number surrounded with a yellow
  circular boundary.
• Three options for the possibility of what time
  interval can these numbers represents
• Each number can represent one second interval.
• Each number can represent increment of a second
  like each digital number can represent half
  second period or each two numbers is equal to one
  second interval.
• Each number can represent two seconds intervals.

4
0
3
2
1
10
Comparing the two types of Countdown Timers
The rectangular screen installed above the
traffic signal.
Improving the solid yellow light to circular
boundary with numbers in the middle.

• Numbers are big enough to read from a distance.
• Costs more (Installation and maintenance).
• maybe hard for some drivers to find the
  correlation between the timer and the yellow
  light.
• If the timer shuts down for any reason we still
  have the signal working but if both were shut
  down so that can happen even without timer
  installed.

• Numbers will be much smaller and hard to read
  from a distance, however the first couple drivers
  approaching the intersection will be able to read
  them.
• Costs less, as we are only improving the traffic
  controller itself and maintenance will be the
  same as the present controller.
• Easy to understand for most drivers.
• Still following the MUTDC regulations by keeping
  the circular yellow shape light.

11
Discussions
Would this encourage drivers to speed up and
cause even more accidents?

• First we are not talking here about the drivers
  who would want to break the law anyway whether
  there is countdown timer or not.
• A considerable portion of drivers in the dilemma
  zone will proceed when they observe the traffic
  signal changing to red. (High speed, Low reaction
  time, variable deceleration rate).
• Worst case scenario
• An aggressive driver approaching intersection
  while yellow timer is on
• Timer just changed from two to one
• Driver is in the dilemma zone, pressed on gas
  trying to speed up and cross the intersection
  before it turns red
• He thinks that he has only one second left
• In reality he has two seconds to pass the stop
  bar and cross the intersection plus 2 second of
  all red time..
• Can you think about a worse case scenario?

12
Discussions Day time and night time
How do think this timer will be effective at
night time when visibility is much less and
numbers could be hard to read?

• We can program the timer for a daytime and a
  night time setting. From 1000 PM to 600 AM the
  solid yellow light can be displayed instead of
  the numbers.

13
Questions that might come across our minds

• What if a truck blocked the view and the driver
  behind the truck is no able to see the timer? ?
  can happen in both cases timer or no timer.
• What if the people get used to see the timer and
  the timer shut down for some time? ? stop sign as
  usual
• What attracts you more regular sign on highway or
  digital screen that displays the speed limit? ?
  not sure. But according to some drivers I
  surveyed, they stated that it is very helpful to
  know when the green light will turn on after the
  pedestrian countdown is off, and therefore they
  though that countdown timers for vehicles would
  be as useful.

14
Thank you for your time and attention..