# Presentation: 740207

## Results of the SAVE-IT Program 

- Matthew R Smith
- Gerald J Witt
- Debi L. Bakowski
- May 13, 2008

## SAVE-IT Program Summary(SAfety VEhicles using adaptive Interface Technology)

- Program start date: March 2003
- _Program mission_: To demonstrate a viable proof of concept that is capable of reducing distraction related crashes and enhancing safety warning effectiveness
- 5 year research and development program sponsored by NHTSA, administered by Volpe
- Team participants: Delphi (lead), Ford (VIRTTEX), University of Iowa & NADS, University of Michigan Transportation Research Institute (UMTRI)

## What is the SAVE-IT system?

## SAVE-IT Research Structure

- (1.5 years)

- (2 years)

- (1.5 years)

## Crash Reduction Effectiveness vs. Acceptance 

- Realism

**Higher**

**Lower**

- Test
- track

- Crash Reduction Effectiveness vs. Acceptance
- Research Venue

- Ability to control environment facilitates the evaluation of safety effectiveness

- On-road

- Driving
- Simulator

**Effectiveness**

**Acceptance**

- Control

**Lower**

**Higher**

- Acceptance evaluation requires realistic exposures

- < 200k
- miles

- 137k
- miles

- 83k
- miles

- 2 police-reported crashes expected every million miles

## Adaptive Warnings

## Support from the 100-Car Study:

- Distraction as the catalyst for Crashes

_**From the 100-Car Study**_**:**
- Forward inattention more frequent for crashes than incidents and near misses
- Suggests that distraction converts incidents into crashes by undermining an avoidance maneuver that likely would have been successful.

**Precipitating Event**
- (e.g., lead vehicle braking event)

**Avoidance Response**
- (e.g., host vehicle braking)

**Event**
**Outcome**
- Incident *(Successful avoidance)*
- Near-Miss *(Late avoidance)*
- Crash *(Unsuccessful avoidance)*

**Contributing Factors**
- (e.g., distraction, drowsiness, impairment, road conditions)

## Adaptive Warnings Development

- Adaptive warning goals:
- reduce annoyance
- improve or minimally degrade crash reduction potential.
- technology must be affordable
- For affordability and simplicity, only head-pose used (cognitive distraction, eye-gaze, and intent not used)
_**Forward Collision Warning**_
- Adaptive timing was selected for the evaluation phase
- When head pose away, timing proportional to duration of away head pose
- When head pose forward, only late alerts provided.
- Earlier warnings were shown to improve effectiveness during distracted episodes
- During attentive episodes, conflicts were usually resolved prior to a delayed warning.
_**Lane Departure Warning**_
- Total suppression selected for the evaluation phase
- When the driver’s head pose was forward, alerts were completely suppressed
- Testing revealed that alerts provided little benefit during attentive episodes

**Collision Percentage**

## Benefits and Acceptance of Adaptive Warnings:

- Test Track Results

- Test track used to accelerate driver understanding of the SAVE-IT systems
- Experience nuisance
- Experience suppression
- Experience earlier alerts
- Two surprise FCW braking events (using surrogate target) provided while drivers engaged in IVIS task
- Alerts were delivered earlier during the distraction episodes as designed
- Earlier alerts resulted in significantly faster reaction times
- Adaptive FCW rated as significantly more useful than non-adaptive
- Drivers agreed significantly more with  “...I would want a ___ on my next car” for adaptive than non-adaptive FCW

## Benefits and Acceptance of Adaptive Warnings: On-road Results

- A subset of the test-track drivers later drove the SAVE-IT vehicle around Michigan
- Two circuits with 2 hours of adaptive/distraction mitigation, and 2 hours of nominal warning systems and no mitigation
- Results revealed substantial alert suppression for both FCW and LDW
- LDW alerts were reduced by 88 percent
- FCW alerts were reduced by 60 percent and proportionally more false alerts (80%) and lane-change alerts (77%) were reduced than same lane alerts (65%).
- The earlier timing during non-forward episodes also added extra alerts.

## Distraction Mitigation

## Demand-Based IVIS Distraction Mitigationand call screening

- All IVIS Features
- Are Available

- Few IVIS features are
- available and almost
- all are advised against

- Many IVIS Features are available and many are advised against

**Driving **
**Demand**
*(from Radar, *
*Yaw, Path, *
*Wipers, etc.)*

**IVIS**
**Function**

- _High_

- _Medium_

- _Low_

- _Park_

- Almost all IVIS Features
- are available and few
- are advised against

- Driver selects
- “call screening” mode

- No Screen (lets all calls through)
- Do not disturb (let no calls through)
- Auto Screen (screening based on demand)

## Distraction Mitigation: Trip Report

- By saving feedback to end of the drive, avoided providing additional distraction
- Acceptance data on trip report was positive and response times to lead vehicle braking were significantly reduced

## SAVE-IT Conclusions

- Adaptive warnings help alleviate the tradeoff between providing sufficient warning during distracted episodes and annoying drivers when they do not need the warnings
- The challenge of adaptive systems is to function differently across driver states while preserving the perception of consistent system behavior
- Providing earlier alerts during distracted episodes appears to best match the driver’s expectations for FCW systems and can help negate the effect of distraction
- Trip report demonstrated high acceptance and significantly reduced response times on subsequent trials
- There were many positive results, however, more work would be beneficial
- The lessons learned during evaluation could be applied to improve the system further
- In many cases, statistical power was insufficient or exposures insufficient for detecting statistically significant results.
- Ford VIRTTEX results are still being analyzed...

## For more information

- Many SAVE-IT documents are available at:
- More information on NHTSA activities and papers in this area are available at:

- _[http://www.volpe.dot.gov/hf/roadway/saveit/index.html](http://www.volpe.dot.gov/hf/roadway/saveit/index.html)_

- _[http://www.nhtsa.gov/portal/site/nhtsa/menuitem.8f0a414414e99092b477cb30343c44cc/](http://www.nhtsa.gov/portal/site/nhtsa/menuitem.8f0a414414e99092b477cb30343c44cc/)__ _