IPDE Process
Chapter 4
IPDE Process
 Need for organized system to drive
 Reduces close calls and collisions
 Manage risk
 Driving Risks – 3 Components
#1. Risk Factors due to Driver, even other drivers
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Adjusting radio
Emotion – anger/your boyfriend/girlfriend just broke up with you
Primping – combing hair, putting on mascara, shaving
Drinking alcohol
Cell phone use
#2. Risk Factors due to Automobile
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Bald Tires
Poorly adjusted brakes
Ineffective Windshield Wipers
Broken Headlight
Dirty Windshield
IPDE Process
 Driving Risks –continued
#3. Roadway Risks
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Bright sun
Construction
Snow / Ice
Sharp Curves
 Good drivers make every effort to manage & lower risks
 IPDE Process – organized system of see, thinking, making judgements
and responding
 Identify – use visual search pattern to look for
 Clues
 Other users of the HTS (Highway Traffic System) assume they will make mistakes
example: speeders
 Road Conditions – hills, curves, lane changes, bicyclists, pedestrians, intersections
 Traffic Concerns
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IPDE Process
 IPDE Process – organized system of see, thinking and responding
 Identify – use visual search pattern
 Smith System - 5 Rules that help drivers develop good seeing habits
 Aim High In Steering – look 12-15 seconds ahead of your vehicle
 Keep Eyes Moving
 Get the Big Picture
 Make Sure Others See You
 Leave Yourself an Out
 Zone Control System – organized method of managing the 6 zones around your car
- see a zone change – check other zones – create
space for
yourself by adjusting
speed & lane position
– Communicate
 Open Zone – no restriction
 Line of Sight – intended path of travel
 Target Area – center of intended path
 Closed Zone – zone not open - restricted “line of sight”
o Examples: stop light (front zone), parked car (right front zone)
IPDE Process
 Zones – pg 65 & 66
Left
Front
Zone
Left
Rear
Zone
Front
Zone
Rear
Zone
Right
Front
Zone
Right
Rear
Zone
IPDE Process
 3 Searching Ranges
 Target Area Range
 Distance ahead of vehicle
 Use to evaluate path
of travel
 12-15 Second Range
 Space will travel in next
12-15 seconds
 4-6 Second Range
 Space will travel in next
4-6 seconds
Target
Area
Range
12-15 Second
Range
4-6 Second Range
IPDE Process
 Checking Your Zones
 Orderly Visual Search Pattern
 Sample: Driving Straight:
 Target Area
 Left Front – Front – Right Front in 12-15 sec range
 Rear Zone - Rearview mirror
 4-6 second range
 12-15 second range
 4-6 range
 Rearview mirror
 Speedometer & Gauges
o Don’t stare
o Practice as a passenger
IPDE Process
 Field of Vision – area see around you
 Most of us can see 90 degrees to each side = 180 degrees
 Central Vision – right in front of you 10 degrees – see clearly
 Peripheral Vision – area see to right or left –
 Outer edges see less clearly
CentralVision
Peripheral Vision
Peripheral Vision
FIELD OF VISION
IPDE Process
 Review Identify Component:
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Aim High Steering – look ahead (12-15 sec)
Keep Eyes Moving – develop scanning technique
Get The Big Picture
Develop Selective Seeing
 Choose only events that impact your driving!
 Open zones that may close
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Examples: Parked car with wheels turned or exhaust from tail pipe
 Look for other Users- anticipate them doing the wrong thing!
 Examples: Speeders
 Look for Roadway Conditions –
 Intersections, Hills, Lane changes, road surfaces, bicyclists, pedestrians
IPDE Process
 Predict – once you identify - predict how it may effect you
 What is happening, what could happen, how could this effect you??
 Example: Pg 72 – bicyclist & on coming car to left
 What do you do?
 Knowledge & Experience will help you identify & predict quicker & faster
 Most predictions related to changes in zones and looking for an out
 Don’t Assume other drivers will make good decisions
 Predict
✔Path of other drivers
✔Action of others
✔Space –Will I have an open zone
✔Pont of Conflict – No open space, where may the conflict occur
–Where paths may cross
• Examples: pg 73
IPDE Process
 The more complex situation, the more difficult to identify & predict
 Speed – Most important factor in control of your vehicle
 Changes with traffic & weather conditions
 Increased Speed decreases time available for IPDE process
 Traction – basic requirement for vehicle control
 Gripping power between tires and road surface
IPDE Process
Decide
 Once you’ve identified a situation…
 Predicted a possible conflict …
 Decide upon the action
 Followed by Execute step
 Examples:
 Maintain speed
 Change speed
 may not always mean slowing down
IPDE Process
Decide
 Examples:
 Change direction – keep a space cushion - continued
 May change lane positions to keep cushion pg 76
o
o
o
o
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Center of Lane
Right Side of Lane
Left Side of Lane
May need to make greater change
Try to detect a changing zone condition 12 sec in advance
IPDE Process
Decide
 Examples: continued
 Communicate with others
 Lights – headlights, taillights, brake lights, turn signal, etc
 Horn
 Car Position
 Eye Contact
 Body Movement
 Combination
 Strategies to keep space around your vehicle
 Minimize Hazard –put distance between self and hazard
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Example: Passing parked cars
IPDE Process
 Strategies to keep space around your vehicle
 Separate Hazards–more than one hazard at a time
 Don’t handle them all at one time
 You do this by adjusting your speed
 Example: On coming car and parked cars on right
 Compromise Space –
 Sometimes hazards can’t be minimized and can’t be separated
 Give as much space as possible to greater hazard
 Example: On coming car moves into your lane with cars parked on
right
IPDE Process
 Execute carry out decision to avoid conflict
 Control Speed
 Accelerating
 Decelerating / Braking
 Check Rear Zone
 Avoid Locking Brakes – loose steering control
o Most cars have antilock breaks – break hard – don’t pump breaks
 Steer
 Don’t over steer – could loose control
 Don’t make jerky sudden movements
 Communicate
 Make it early so other know your intentions
 Combined Actions
IPDE Process
 Putting It Into Action
 Practice – as you ride with others
 Commentary Driving – talk out loud
 Takes Time
 The more complex traffic situation the longer it takes