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Virginia Driver Education. Module Three. Vision, Vehicle Balance and Laws of Nature. Virginia Department of Education. Module Three. Vision, Vehicle Balance and Laws of Nature Topic 1 Starting, Securing and Exiting Topic 2 Vision and Driving Topic 3 Steering and Braking
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Virginia Driver Education Module Three Vision, Vehicle Balance and Laws of Nature
VirginiaDepartment of Education Module Three Vision, Vehicle Balance and Laws of Nature Topic 1Starting, Securing and Exiting Topic 2Vision and Driving Topic 3Steering and Braking Topic 4Laws of Nature Topic 5Establishing Vehicle Reference Points
Topic 1 - Starting Tasks • Check/set park brake (P) and place • Right foot on brake pedal, heel on floor • Left foot on “dead pedal” for balance • Key in ignition, and turn toward start • Check alert, warning lights and gauges • Adjust ventilation, accessories, etc • Turn headlights on
Securing the Vehicle • Find a legal, safe parking place • Stop and set parking brake • Shift gear selector to (P)ark (Shift to Reverse if Manual Transmission) • Close windows • Turn off accessories • Turn ignition switch to “off” • Lock ignition switch and remove key • Unfasten occupant restraints
Exiting the Vehicle • Check traffic flow to rear prior to opening door • Monitor door swing into adjacent lane or when parked next to another vehicle • Exit quickly to avoid conflict with traffic • Lock doors • Walk toward rear of the vehicle facing traffic
Topic 2 - Vision and Driving • Drivers base about 90% of all driving decisions on what they see, and 10% on what they hear or feel • Drivers must be able to look far enough ahead to make good decisions about speed, lane position, signs, signals, markings, and potential hazards • Drivers must be able to see near and far--close enough to read the speedometer, and far enough ahead to see/adjust for hazards
Visual Testing Visual acuity is the measurement of the finest details which can be seen in optimal light conditions
Effective Use of Visual Fields The Three Visual Fields • Fovea Vision • Visual Lead, Targeting, Signs, Signals • Central • Referencing, Path of Travel • Peripheral Vision • Motion and Color Changes
The Fovea Vision Area Located at the center of the central vision area, the fovea is a small part of the retina and is responsible for our highest visual acuity
Central Vision Central Vision Area (Inner Fringe) An area 35 to 38 degrees around foveal vision used for: • Referencing Vehicle Position to Roadway • Viewing Path of Travel
Central Vision at Night • The human eye’s field of vision is much smaller without the help of natural light • Depth perception, visual acuity, and color recognition are all compromised at night • Minimize glare by looking at the bottom right of the road to avoid approaching headlights • Keep it dark in the car • Slow down to give yourself longer to react
Peripheral Vision Approximately 90of vision to each side Increases total field of vision to about 180-190and is used to see: • Objects to the side • Movement and color changes to the side
Peripheral Vision and the Driving Task Drivers use peripheral vision to: • See color and object movement • See signal changes, road signs, warning lights on the dashboard • Monitor traffic • Stay within the lane
Night Time Peripheral Vision • Is reduced dramatically due to lack of light to retina and glare • While Foveal and Central Vision are also reduced, they become more critical for searching for problems
Vision is Affected by • Smoke • Age • Dirty Windshield • Poor Windshield Wipers • Poor night vision • Night Blindness • Speed • Fatigue • Drugs • Poor weather • Darkness • Glare • Inattention
Depth Perception • Need both eyes to judge the distance between two objects • Depth perception allows you to: • judge gaps in traffic when turning, merging, or passing • judge distance when approaching a vehicle or obstruction
Poor Depth Perception • Stop too far from the stop line or intersection • Stop too close to vehicles ahead • Move into gaps that are too small • Look for gaps that are larger than needed to perform a maneuver • Follow other vehicles at unsafe following distance • Hit parked cars when parking • Have “close calls” when entering traffic, passing, etc.
As speed increases • Central vision decreases and blurs • Peripheral vision decreases • Changes in steering exaggerate vehicle movement VISION FIELDS NARROW
Ways to Improve the Vision Fields • Clean windows—inside and out • Clean lights—be sure they work • Check defroster and wiper blades • Remove any objects that interfere with vision • Adjust mirrors properly • Keep sunglasses, flashlight, windshield scraper in vehicle
Line of Sight • Line-of-sight is the distance you can see in your path of travel
Line-of-Sight (LOS) Restrictions • Vision is blocked, speed and position adjustments may be needed until LOS is restored
Path-of-Travel (POT) • The space the vehicle will occupy while traveling to the target area
Examples of Path-of-Travel Restrictions • Space is not available for the vehicle Vehicle stopped or blocking intersection Narrow lane and no shoulder
“Target” Far Ahead in the Path of Travel Identify the target in this driver’s path of travel A “Target” is an object or place far ahead in the center of your path of travel
Target AREA Provides the BIG Picture The Target area is the area drivers must scan to the left and right of the target Target Area
Advantages of Targeting • Easier to track vehicle in a straight line • Driver looks far ahead of the vehicle, and at the same time gathers information close to the vehicle • Driver can plan ahead to better manage risks • Targeting develops visual skills essential for managing traction loss and steering control
The Pavement Around Your Vehicle You Cannot See From the Driver’s Seat The driver cannot see anything on the ground in the area outlined above—cars are used to show the size of this area
Determining Driver Blind Areas Marker (foot or cone) Place markers (cones, people) at the point where the driver can see the marker, (cone, person’s foot) in contact with the ground
Using Lane Position to Maximize LOS 1 • Select the lane position that gives you the best line of sight and safest path of travel • Lane positions are based upon an average lane size of 12-feet wide, and a vehicle 6-feet wide 2 3 4 5
Lane Position 1 2-3 Feet 2-3 Feet Positioned in the center of lane with an equal buffer of space on either side
Lane Position 2 3-6 Inches Allows for 6 feet of space to the right of the vehicle. Used to prepare for a left turn or when avoiding a problem to the right of the vehicle.
Lane Position 3 3-6 Inches Allows for 6 feet of space to the left of the vehicle. Used to prepare for a right turn or when avoiding a problem to the left of the vehicle.
Lane Positions 4 and 5 4 5 Lane positions 4 and 5 – straddling the line to avoid a problem within a lane
Topic 3 - Basic Maneuvers -- Steering • Holding the upper half of the wheel can result in excessive steering, air bag injuries, and upper body fatigue • Hands located on lower half of the • wheel offers: • Relaxed, balanced control • Reduces unwanted steering wheel movement • Improves stability by lowering the body’s center of gravity
Hand-to-Hand/Push-Pull Steering Hand-to-Hand Steering/Push-Pull Right Turn Left Hand Pushes Up from 8 to 11 Right Turn Right Hand Pulls Down from 1 to 4
Hand-Over-Hand Steering Used at Speeds below 15 mph Used for slow, tight turns - Arms cross on the top 1/3 of the wheel until desired path of travel is reached Left Turn/left hand Left hand pulls down, then reaches up to about theo’clock position and continues to pull 11-12 down to the left Left Turn/right hand Right Hand pushes up to about the 11 o’clock position
One-Hand Steering • Is used when: • Backing straight--hand holds top of wheel • Backing a trailer--hand holds bottom of wheel Backing Position
Covering the Accelerator • Used for a smooth transition from braking to accelerating • Allows the vehicle to coast which may speed up or slow down the vehicle • Permits the driver to be prepared for any needed acceleration
Foot Pedals Right foot pivots between brake and accelerator Brake Accelerator Dead Pedal Left foot “rests” on dead pedal
Acceleration Techniques • Progressive, Smooth Acceleration • Heel pivots foot from the brake to the accelerator • Gently apply pressure to the accelerator pedal to gradually increase speed to minimize backward pitch and maintain vehicle balance
Acceleration Techniques (cont) • 2. Thrust Acceleration • Typically used when passing or merging into higher speed traffic • Greater pressure is applied to accelerator pedal to rapidly increase speed without losing tire traction
Braking Techniques Smooth braking technique: • Is a trait of a skilled driver • Saves wear and tear on the brake system and tires
Methods to Reduce Speed Release the Accelerator • Most frequently used method to slow vehicle speed • Gradually reduce pedal pressure to avoid abrupt changes in speed
Methods to Reduce Speed 2. Controlled Braking - When releasing the accelerator is not enough • Check the rear view mirror • Release accelerator and apply smooth, steady pressure on the brake pedal • For a smooth STOP, gently ease off the brake a few seconds before stopping to reduce the vehicle’s weight shift so the car does not pitch forward then backward during the final phase of stopping
Methods to Reduce Speed (cont) 3. Threshold Braking in an Emergency Slows the vehicle as quickly as possible without locking brakes or losing traction • Release accelerator while checking traffic behind • Exert forceful pressure on brake pedal and you will feel the vehicle weight shift forward • If you feel the wheels begin to slide, ease the pressure on brake pedal so the tires can begin rotating again
Methods to Reduce Speed (cont.) 4. Trail Braking – Used for Sharp Turns Occurs at the transition point where you slightly reduce pressure on the brake pedal to allow the vehicle to begin to regain speed before applying the accelerator
Trail Braking 1. Use controlled braking prior to reaching the curve 2. Begin easing off brake, and trail brake with very light pressure until halfway through the turn, 3. Accelerate out of the turn
Anti-Lock Braking System (ABS) ABS allows maximum stopping force without locking up the brakes (skidding) If standard brakes are applied too hard, the wheels "lock" or skid, and you lose steering control.
Anti-Lock Braking System (cont) If steering control is lost, the vehicle skids in a straight line wherever it is going ABS is an anti-lock/anti-skid brake system that allows the driver to steer during hard braking
Anti-Lock Braking System (cont.) • The ABS warning will come on when there is a problem with either the ABS brake system, normal brake system, or the brake fluid is low in the master cylinder or the ABS brake system • To find out if a vehicle is equipped with ABS, turn on the ignition and check the instrument panel for the ABS indicator light