Field Evaluation of an Advance Brake Warning System

Presented by Adhit Dhar and Cortlon Snyder

Advanced Braking Warning systems (ABW) are devices installed on automobiles that will trigger a car’s brake lights before the driver will press the brake pedal.

What is ABW?

PurposeThe purpose of this article is too study

the effects of a advanced brake light warning system.

The main goal of this article is to conclude whether or not the warning system is a driving hazard.

Background SupportStudy regarding rear-end collisions

National Accident Sampling System (NHTSA, 1994)

Study of center high-mounted stop light(McKnight and Shinar, 1992) (Sivak, Post, and Olsen, 1981)

Study of reductions in rear-end collisions(Kahane, 1989)(Rausch, Wong, and Kirkpatrick, 1982)

Study on advanced brake warning system(Morrison, Swope, and Halcomb, 1986)(Olsen, 1988)

Theoretical BasisThe theoretical basis is to study the

effects of the advanced braking warning system and its effects on safety. A study was performed to prove the system is not a driving safety hazard.

Practical ContributionsA practical contribution this article

provides is proof that this system is not a safety hazard. Thus, if cost-feasible, it should be implemented in automobiles to reduce the number of rear-end collisions.

Theoretical ContributionThis study could improve the design of

future automobiles if they are all built with ABW systems. In this case, it could lead to other studies regarding vehicle safety.

Methodologies-Subjects aged 18-65 yrs, median age 38 yrs-743 trips made, averaging 83 km per trip-6 Community cars used with Advanced Brake Warning-Men made 80% of trips-Sensor placed on rod of gas pedal, attached to brake

lights-System initiates 2 minutes after car starts-Electronic event recorder installed behind dashboard5 Types of Events Recorded-Total number of braking actions-Total number of ABW activations-Number of braking actions < 1 s (brief braking actions)-Number of ABW activations followed by braking within 1

s-Number of ABW activations followed by brief braking (<

1 s) within 1 s

Statistical Analysis-Total brake applications and # of brief

brakes (braking for < 1 s) correlated highly with km driven, with r = 0.96 and r = 0.89 for each, respectively

-But, correlations between km driven and abrupt braking triggering ABW + brakes was only 0.34, and not significant at p < 0.05 (2 readings from each car)

-Correlation between total braking actions and ABW + brakes failed to reach statistical significance at r = 0.34

Presentation of Results-6 vehicles driven for a total of 61,668 km

and generated 95,394 brake applications

-820 brake applications were abrupt enough to activate ABW system (0.9%)

-ABW activation followed by brake application occurred at a rate of 13.3 times per 1,000 km

-False alarms occur at a rate of 23%, or 4 times per every 1000 km traveled

-Brief braking occurred at a rate of 167 times per 1,000 km

Reasonable ConclusionsABW system does not appear to pose a

safety hazard, and can benefit rather than harm traffic safety due to the fact that:

-With brief braking actions occurring 167 times per 1000 km, false alarms are very rare

-In normal course of driving, ABW system would activate brake lights without braking occurring only once out of 50 times

Future Work/ResearchExperiment leads to many possibilities:

-More females subjects can be tested in a new study

-Stopping distance can be recorded for trailing cars under many different scenarios

-Experiment can be run in a more rigorous setting like the NASCAR circuit