SLIDE 1:
NHTSA’s 2005 ESC Research Program:  
An Overview

Garrick J. Forkenbrock
NHTSA VRTC


SLIDE 2:
Presentation Overview

* Program Objectives
* Background
* ESC Effectiveness Research
* Government and Industry Cooperation
* Conclusions
* Sources for Additional Information


SLIDE 3:
Program Objectives
- Validate and refine NHTSA’s proposed ESC identification criteria

- Work with industry to collaboratively gather data 


SLIDE 4:
Background

2004 Research Objectives:
Perform research supporting the development of maneuvers capable of objectively assessing handling

Results from the handling tests would supplement NCAP rollover ratings

Five diverse test vehicles used

Evaluated with ESC enabled / disabled 


SLIDE 5:
Background (continued)

Midway through 2004, NHSTA expressed an increased interest in ESC effectiveness

Focus of maneuver development changed from handling to ESC effectiveness

By late 2004, NHTSA had isolated a reduced suite of test maneuvers and proposed ESC effectiveness criteria


SLIDE 6:
ESC Research
Effectiveness Criteria

A vehicle with an effective ESC should:
- Not spinout* 	(lateral stability measure)
- Be able to achieve a minimum lateral displacement* (responsiveness measure)
- Not produce two-wheel lift
- Not produce rim-to-pavement contact or tire debeading

These criteria must be satisfied during one of four specialized maneuvers presently being evaluated



SLIDE 7:
Test Maneuvers
Performed With A Steering Machine
Slowly Increasing Steer 
	(for characterization use only) 
0.7 Hz Sine with Dwell
0.7 Hz Increasing Amplitude Sine
500 deg/s Yaw Acceleration 
	Steering Reversal
500 deg/s Yaw Acceleration
	Steering Reversal w/Pause


SLIDE 8:
Test Conditions

ESC enabled and disabled

Test surface
 * Dry, high-mu asphalt
 * Maneuvers initiated while vehicle is being driven up a 1% grade

Nominal load
 * Driver
 * Instrumentation
 * Outriggers if vehicle is an SUV, pickup, van, minivan, station wagon, or crossover vehicle


SLIDE 9:
What is a “Spinout”
Preliminary Definition



SLIDE 10:
What is a “Spinout” 
Threshold Example


SLIDE 11:
What is a “Spinout”
Sample Video [disabled]

0.7Hz Sine with dwell

2004 volvo XC90 
ESC disabled
SWA  120 degrees  - threshold NOT exceeded


2004 VOlvo XC90
ESC disabled
SWA = 130 degrees - threshold exceeded



SLIDE 12:
Lateral Displacement
An effective ESC should not impede responsiveness 
 * Proposed minimum lateral displacement:  12-ft
 * Must be achieved prior to completion of a maneuver performed with dmax

Measured via GPS during testing
 * Referenced to pre-maneuver heading

NHTSA’s evaluation criterion will not penalize vehicles equipped with rollover mitigation technology


SLIDE 13:
Lateral Displacement
Threshold Example

[graph]
0.6Hz increasing amplitude sine, lateral displacement = 12.2 ft

2004 GMC Savana
ESC enabled 
SWA = 160 degrees



SLIDE 14:
Lateral Displacement
Effects of an RSC 
[graph] 0.7 Hz Sine with Dwell, 
Lateral Displacement = 13.7 ft 

2004 Volvo XC90
ESC enabled
SWA = 300 degrees


SLIDE 15:
Government and Industry Cooperation

NHTSA hopes to collect data from 50 vehicles in 2005 

- Will help select the most efficient maneuver capable of determining whether a vehicle is equipped with an ESC 

- Used to improve the robustness of the spinout model 

- Will help assess the lateral displacement capability of ESC-equipped vehicles


A cooperative testing effort between NHTSA and industry is underway

- Test data from industry-evaluated vehicles is critical



SLIDE 16:
Conclusion

- ESC research is a top priority for NHTSA 

- Preliminary ESC effectiveness criteria have been identified

- A cooperative testing effort between NHTSA and industry is underway 



SLIDE 17:
Additional Information

ESC Docket
http://dms.dot.gov/search/searchFormSimple.cfm
Number 19951

VRTC ESC Website
http://www-nrd.nhtsa.dot.gov/vrtc/ca/esc.htm