Unit 5 DriversEd

note

effective use of vision is critical to safe driving 60% of the human brain is devoted to vision and 90% of driving is visual.

visual lead

distance the driver looks ahead (20-30 sec from the front vehicle)

search process

start from the visual lead area, search for traffic, flow information and potential risk situations

line of sight

imaginary line that extends from the eyes to the point of focus, can be blocked by a curve, hill, tree branches, buildings, and large vehicles

field of view

the entire area of the highway and surroundings that the driver can see at any given moment

path of travel

space into which the driver can safely direct the vehicle with the lowest possible risk

3 types of vision

central vision
fringe vision
peripheral vision

central vision

a narrow five degree cone that makes up only 3% of a driver's total visual field

fringe vision

used to judge depth and position

peripheral vision

is conical in shape around the other vision fields

IPDE

formula for managing driving hazards
1. identify anything that can affect your driving
2. predict the worst thing that can happen with what you have identified
3. decide to slow down and cover brake when approaching a stale green light, slow down when traveling on dirt road due to decreased traction, cover brake and slow when approaching a car wanting to turn left when my path of travel is straight and actively scan the movements, etc.
4. execute the act of moving your foot over the top of the brake pedal to cover it

smith system

gives broad overview of the driving environment. 5 principles:
-aim high and look ahead
-keep your eyes moving
+ survey the entire environment; glance left and right; check side view mirrors every 20-30 sec; note what other drivers are doing
-get the big picture
-leave yourself a way out
-make sure others see you

following distance

the distance between your vehicle and the vehicle ahead. which gives you more space between vehicles in case of an emergency
-rule: driver should stay at least 2 sec behind any vehicle.
- increase following distance when
+ roadways are slippery
+ visibility is poor
+ driving at night
+ following large vehicles
+anticipate in-car distraction
+ towing

total stop distance

[thinking distance]+[braking distance]=[total stopping distance]

braking distance

the time it takes for your car to come to a complete stop after you've hit your brakes. When you double braking distance quadruples. As shown below, every time you double your speed, you multiply your braking distance by four.

thinking distance

the amount of time it takes for you to decide to hit the brakes, and then actually hit them. When you see a potential threat, sign, or traffic control on the road, you don't break instantaneously. You may need a sec or two to move your foot to the brake pedal. Reaction time can be slowed down if the driver is sleepy, sick, impaired, or distracted. Make sure you're sober and alert every time you drive, because sometimes an extra sec can make all the difference.

braking distance

related to
-speed of vehicle
-driver perception time(length of time it takes to see and recognize a dangerous situation)
-driver reaction time(time form perception of danger to start of braking- the average is 0.75 sec)
-type and condition of tires, brakes, and of the pavement
-vehicle weight when loaded or towing

situations

-driving on slippery roads, you should double your following distance to 6 sec or more to allow for extra distance needed to adjust your speed or to stop
-when the driver behind you wishes to pass, reducing your speed will allow that driver to pass more quickly. the added distance will make it easier for the passing motorist to pull back into the lane.
-when you are following a large vehicle, such as a tractor-trailer, that blocks your field of vision of the road ahead, you will need extra distance to see around

motor vehicle operators

requires visual, cognitive, and motor skills. These 3 skills are transformed into 3 terms:
-search
-evaluate
-execute

mv: search

to actively scan and identify factors that could create increased risk

mv: evaluate

to consider potential problems arising form the interaction of 3 factors

mv: execute

refers to the physical motor skills used to prevent or avoid the resulting

type of collisions

head-on collision
hit from behind(rear-ended)
hitting the driver in front
side collisions

head-on collision

are particularly dangerous and can be deadly. The key to avoiding them is to keep looking ahead down the road for possible problems. If a crash looks like it's coming, slow down and even go off the road to the right to avoid a hard crash

hit from behind(rear ended)

avoiding being hit from behind
signal your intentions when stopping or turning; be alert for tailgaters; slow down gradually; and leave room in front of you when stopped so that if you are hit from behind, at least you won't hit another vehicle in front

hitting the driver in front

to avoid colliding with a vehicle in front, take these precautions:
look well ahead for hazards, brake lights, and turn signals; and always maintain a sufficient distance between you and the vehicle in front so that you have enough room to stop safely

side collisions

to avoid side collisions, be sure to approach all intersections with caution. Always look both ways before proceeding- even if you have the right of way. Do not force your way through an intersection if another driver is set on going first. It is better to let the other driver go ahead of you than it is to get into an accident which can be costly and perhaps dangerous to you and to others

Avoiding crashes

-scan the road and shoulders ahead of you. Looking ahead helps provide enough reaction time if an animal is spotted. Also, remember some animals move in groups, so when there is one, there are usually more in the area.
-use high beam headlights if there's no oncoming traffic. Wildlife may be spotted sooner when using high beams. This will give the driver time to slow down, move over or honk the horn to scare the animal away
-if a collision is unavoidable, apply the brakes firmly and remain in your lane. swerving to avoid an animal can often cause a more serious crash or result in drivers losing control of vehicles.
-be extra cautious at dawn and dusk. Most animals, especially deer, tend to be more active early in the morning and at dusk.

stats

-more than 90 people die in car accidents per day
-around 2 mil. drivers in car accidents experience permanent injuries every year
- 6 mil. is the average number of car accidents in the US every year
- 3 mil. people in the US are injured every year in car accidents
-1 in 7 people do not wear seat belt while driving
-seat belts reduce the risk of death by 45%
- people not wearing a seat belt are 30 times more likely to be ejected from the vehicle during a crash
-seat belts cut the risk of serious injury by 50%

Accident prevention programs

NC Vision Zero
Doug Herberts: BRAKES
Ford Driving Skills for Life
AAA: Keys2Drive, The AAA guide to teen driver safety