# Presentation: 927673

## Research Elements of Integrated Vehicle Based Safety Systems

**Research Elements of Integrated Vehicle Based Safety Systems**

**Jack Ference, IVBSS Technical Manager**
**ITS America Annual Meeting**
**May, 2005**

## What is IVBSS?  

**A New *****Tier I***** Initiative**
**Vision:  **
- 	All vehicles would be equipped with integrated driver assistance systems to help drivers avoid the most common types of crashes.
**Goal:****  **
- 	To work with industry to accelerate introduction of integrated vehicle-based safety systems into the U.S. vehicle fleet.
**Addresses** 3 Crash Types**:**
- Rear End
- Road Departure
- Lane Change

## Who’s Involved

**Program Manager:**  Jack Ference

**Program Coordinator:**
- Mike Schagrin, FHWA ITS JPO

**Commercial Vehicle Lead:**
- Tim Johnson

**Evaluation Leader:**  Wassim Najm

**Transit Vehicle Lead:**
- Brian Cronin

## Program Timeline

**7/04**

**Gov’t-initiated activity**

**Partner-led activity**

## Program Activities & Tasks

**Gov’t-initiated activity**

**Partner-led activity**

**Gov’t-Industry activity**

## There are many research issues to look at:

**Multiple threats and Prioritization of warnings**
**Ways to avoid a crash**
**Behavioral adaptation**
**Non-useful warnings (includes false warnings)**
**Effective DVI design**

## Multiple Threats

- A major issue with multiple warnings is not only alerting the driver to the presence of multiple threats, but communicating the hazard type and appropriate response.

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
The problems associated with multiple warning systems include:
Alarms may compete with one another for the driver's attention and may cause confusion, thus interfere with an appropriate response if more than one activates simultaneously or nearly simultaneously.  For example, a FCW prompts the driver to take evasive action that triggers a road departure warning.
Drivers may take longer to respond to a hazard due to the increased time to identify the specific type of warning when more than one system is present on the vehicle, even if only one alarm is activated.
Multiple alarms may violate driver expectations of independent system function.  For example, if a driver has experience with a side obstacle warning system then is driving a vehicle that has both SOW and FCW, does a FCW interfere with correct response to the SOW?
Each additional warning system will introduce increased numbers of false and nuisance warnings, which may decrease the credibility of the systems and their alerts, thereby decreasing driver acceptance.
The alerting benefits of all alarms may decrease due to the increased workload and attentional demands of frequent alerts, which will increase with multiple, independent warning systems.

## Multiple Threats

**Example:**  FCW + Lane Change Warning

- *From Chiang, Brooks, and Llaneras, Nov 2004,
- “Investigation of Multiple Collision Alarm Interference
- Driving Simulator Study”

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
Freeway onramp.  Subject vehicle merges at highway speed.
Lead vehicle changes lanes abruptly into path of subject vehicle.  FCW issues at same time.
Driver distracted and fails to see car in adjacent target lane (blind spot)
LCW issues alert as driver begins to change lanes, when left wheel of subject vehicle is 1 ft. into left lane
Conflict vehicle becomes visible to driver after LCW warning is issued

## Multiple Threats

- How can **multiple threats that occur at near-simultaneous points** in time be communicated to the driver?
- Is multi-modal presentation **more or less effective** than using one modality?
**Can drivers discriminate** between alerts and effectively respond to each threat?
- Can an IVBSS system be effective without **prioritization**?

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
Based on previous work done by Chiang, Brooks and Llaneras last year, the manner in which the warning information is presented and communicated to drivers does appear to impact performance.  The coordinated warning condition (which uniquely coded each warning hazard and coded the direction of the threat) appeared to enhance driver search and led to better overall performance (fewer crashes) relative to the master warning strategy.  It is possible that other types of interfaces may further mediate driver performance.  These include such interfaces as haptic warnings (like seating vibration, steering vibration, or seatbelt tugs), or different alert sound strategies such as continuous sounds or voice feedback. 

The master warning strategy used before in research has adopted a single universal warning tone with unique supplemental visual displays to denote the nature of the crash threat.  Under situations of rapid, sequential warnings, drivers tend to misinterpret the universal signal as a continuation of the first threat condition (apparently relying on the audible warning and not the visual displays).  The added benefits of directionally coding the signal as a means of guiding driver search should be examined.  In general, work should attempt to understand how the implementation of a master warning signal could be improved under the conditions of multiple threats.

## Can a driver successfully be directed how to avoid a crash?
How many scenarios need to be developed to understand what is possible?

Are auditory instructions (such as “swerve left”) appropriate or are there better ways to elicit quicker or appropriate responses from drivers?
For example, a haptic cue or a pedal push may result in quicker response times or less confusion as to how to respond

- How many **scenarios** need to be developed to understand what is possible?
**Are auditory instructions** (such as “swerve left”) **appropriate **or are there better ways to elicit quicker or appropriate responses from drivers?
- For example, a haptic cue or a pedal push may result in quicker response times or less confusion as to how to respond

**Avoiding a crash**

**Key Human Factors ****Research Issues for IVBSS**

## Avoiding a crash

- *From Chiang, Brooks, and Llaneras, Nov 2004,
- “Investigation of Multiple Collision Alarm Interference
- Driving Simulator Study”

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
Multi-lane freeway, daytime
Driver following lead vehicle 
Lead vehicle changes lanes abruptly and reveals stopped in-path vehicle
System informs driver to “swerve left” to avoid crash

## How should the system be designed to minimize adverse behavioral adaptation by drivers?
What is needed to prevent riskier driving behavior due to the perception of increased safety provided by an (effective) crash avoidance system?

- What is needed to prevent riskier driving behavior due to the **perception of increased safety** provided by an (effective) crash avoidance system?

**Behavioral Adaptation**

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
How much do the drivers “trust” the system?  Where is the balance between trusting the system too much and not enough?  There is a danger that drivers will get so used to the system that they in fact drive differently than before it was installed.

## Non useful warnings include:
False alarms
Nuisance warnings
Examples: 
An FCW system detects an object ahead of the vehicle on a curve, out of the intended travel path, but in the radar’s field of view
A driver is already responding to an object detected by a CW system

- False alarms
- Nuisance warnings
**Examples**:
- An FCW system detects an object ahead of the vehicle on a curve, out of the intended travel path, but in the radar’s field of view
- A driver is already responding to an object detected by a CW system

**Non useful warnings**

**Key Human Factors ****Research Issues for IVBSS**

## How will non-useful warnings (including false alarms) affect driver acceptance and system effectiveness?
What is the acceptable level of false alarms and other non-useful warnings?
Additional Examples:
A driver changes a lane without using a turning signal and the system recognizes an off-path target
A false curve speed warning goes off and an off-path target is detected

- What is the acceptable level of false alarms and other non-useful warnings?
- Additional Examples:
- A driver changes a lane without using a turning signal and the system recognizes an off-path target
- A false curve speed warning goes off and an off-path target is detected

**Non useful warnings**

**Key Human Factors ****Research Issues for IVBSS**

**Notes:**
How can the IVBSS be designed to achieve this?

## Sensors and technology may be able to detect a crash threat, but the Driver Vehicle Interface (DVI) must be effective or the IVBSS system will not be successful.

**DVI Design**

**Key Human Factors ****Research Issues for IVBSS**

## How will individual differences and intervening variables such as age be accommodated? What are the DVI implications?
Should a DVI adapt to the state of the driver? (distracted, impaired, alert)
Are there DVI parameters that should be standardized?

- Should a DVI adapt to the **state of the driver**? (distracted, impaired, alert)
- Are there DVI parameters that should be **standardized**?

**DVI Design**

**Key Human Factors ****Research Issues for IVBSS**

## The key to driver acceptance and successful deployment of IVBSS technology will be an effective DVI
There are significant human factors research issues that need to be and will be addressed in the IVBSS program
Creating an effective DVI may be a larger challenge than the integration of system  hardware and software 

- There are **significant human factors research issues that need to be and will be addressed** in the IVBSS program
- Creating an effective DVI may be a **larger challenge** than the integration of system  hardware and software

**Final Thoughts...**

## Contact:

**Jack Ference**
**U.S. DOT /NHTSA**
**(202) 366-0168 **
**jack.ference@nhtsa.dot.gov**

**Notes:**
Here is my contact information. Please feel free to contact me at any time with any questions. Thank you!