Chapter 2. Alternative VDR Concepts - Federal Motor Carrier Safety Administration

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Chapter 2. Alternative VDR Concepts
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Approach

Using industry and government findings (i.e., from NHTSA, FHWA, ATA/TMC) along with surveys and interviews with key industry stakeholders, the contractor team profiled end-user needs and expectations regarding VDR capabilities and required data parameters. VDR concepts targeted at the following end-user applications were then developed:

Accident reconstruction and crash causation
Operational efficiency
Driver monitoring

Each concept was intended to typify the design, functionality, and operational performance that would generally be demanded by these three broad user groups. VDR concepts were initially developed in the abstract-without any constraints as to what may be available in the marketplace today. This was to ensure that they represent the team's best judgment as to what a "minimalist" and "full-featured" VDR might be for each end-user application. This is not to imply that the concepts are not practical and/or implementable using current technology-only that it was not a requirement that the concept have a close parallel in the current marketplace.

Unique (distinct) concepts were developed to represent practical combinations of features and capabilities that would address requirements for differing market segments. Specifically, the following VDR concepts were developed:

A low-cost event-triggered data recorder for recording baseline accident data
A more advanced event-triggered data recorder that incorporates some advanced sensor technologies
A baseline continuous VDR that records maintenance and operational data meant to improve fleet operations
An advanced continuous data recorder that includes additional driver monitoring parameters
A "full-featured" VDR that may include both accident data and operational efficiency data

A profile of each concept was developed that included the source for each data element; necessary network protocols; data collection and transmission rate requirements; and data security, storage, and retrieval needs. Each of these concepts was also defined in terms of an operational scenario-in effect, the conditions under which such a system might be employed, by whom, and for what purposes. This facilitated the accrual of benefit and cost information for subsequent analysis.

Concept descriptions contain, to the extent possible, known and estimated purchase, installation, and operating costs. Because commercial vehicle owners and operators are extremely sensitive to equipment and operating costs, these figures represent important indicators of the commercialization potential of the various concepts.

In addition to the five "core" VDR concepts, which are focused around specific parameters and data sets, a list of advanced VDR features that could be added to any of the five concepts was developed. By separating these advanced VDR features from the five core concepts, and discussing the costs and benefits of these technologies separately, the reader can better understand the costs and implications of adding each feature to a vehicle's data recording system. The five concept data recorders can be thought of as five different "baseline" products that might be appropriate to fulfill the needs of different user-segments. The technologies and features can be thought of as "options" that could be added to any of the baseline products. Using this "base product" and "options" concept allows a reduction of the number of VDR scenarios to be examined while still providing the reader with valuable information needed to effectively construct the reader's own VDR scenarios or configurations.

Recommendations for Data Parameters to Be Monitored

Several industry and government organizations have released findings related to the specific data parameters that VDRs should record. In one case (the NHTSA T&B EDR Working Group), this list included the priority by which these parameters should be recorded.

The NHTSA EDR Working Group presented a summary of findings for light-duty vehicles in August 2001 with an extensive list of data elements that could be considered for EDRs to record along with a Top 10 list of elements based on input from EDR users and manufacturers. In addition, the working group's summary of findings included two lists of EDR parameters important to highway safety research-one from FHWA and one from the TRB.

The NHTSA T&B EDR Working Group developed a detailed list of data elements that were applicable to trucks, motorcoaches, and school buses. The group established two priorities for these data elements. The group deemed Priority 1 parameters to be absolutely necessary to record in order to perform crash causation and accident reconstruction. Priority 2 data elements would improve this ability and should be recorded when available on the vehicle. In addition, the T&B EDR Working Group labeled two parameters (i.e., digital video and vehicle/trailer load present) as optional in that they would greatly assist in performing crash causation analysis and accident reconstruction but currently require the use of advanced onboard sensors (i.e., digital imaging).

In November 1999, the National Transportation Safety Board (NTSB) issued safety recommendations (H-99-45 through H-99-54) to NHTSA to improve school bus and motorcoach safety. One recommendation (H-99-52) required all school buses and motorcoaches manufactured after January 1, 2003 to be equipped with onboard recording systems that record numerous vehicle parameters at a sampling rate suitable to determine vehicle dynamics and are preserved in the event of a vehicle crash or power loss.

The ATA/TMC developed a recommended practice, RP 1214, for VDRs-"Guidelines for Event Recording - Collection, Storage, and Retrieval." This recommended practice defines guidelines for commercial vehicle event data collection (including a list of parameters), storage, and retrieval for post-accident analysis using onboard vehicle ECUs.

The FHWA is conducting an IVI program, Project 134, on the "Development of Requirements and Functional Specifications for Event Data Recorders." One product of the IVI project was a functional specification for a crash EDR that outlined three tiers of data elements:

Tier 1 - The minimum required data elements for a crash EDR on CMVs.
Tier 2 - Additional data elements to the data elements in tier 1 that would permit further analysis of crashes involving CMVs.
Tier 3 - A complete set of data crash elements to thoroughly analyze crashes involving CMVs, including the data elements listed in tiers 1 and 2.

The NHTSA Notice of Proposed Rulemaking, NHTSA-2004-18029, outlined a list of data elements that are required to be recorded on light-duty vehicles equipped with EDRs. It also specified the number of data elements that should be recorded if the vehicle is equipped with the relevant advanced safety system or sensing capability.

Exhibit 2.1 provides a comprehensive list of possible data elements that could be useful for VDRs to record. It summarizes the data parameters that each of the above organizations consider important to record onboard. Entries are listed as follows:

: Considered important to record onboard

1x-10x: NHTSA EDR Working Group (WG) "Top Ten" List

P1: NHTSA T&B EDR WG Priority 1 data elements (see footnote #4)

P2: NHTSA T&B EDR WG Priority 2 data elements (see footnote #4)

O: NHTSA T&B EDR WG optional data elements (see footnote #4)

T1: FHWA IVI-134 Project Tier 1 minimum data elements (see footnote #7)

T2: FHWA IVI-134 Project Tier 2 typical data elements (see footnote #7)

T3: FHWA IVI-134 Project Tier 3 complete data elements (see footnote #7)

R: NHTSA NPRM required data elements (see footnote #8)

IE: NHTSA NPRM elements to be recorded if equipped (see footnote #8)

Exhibit 2.1 - Recommendations for Data Parameters to Be Monitored

Parameters	NHTSA EDR WG Top 10 3	NHTSA EDR WG FHWA 3	NHTSA EDR WG TRB 3	NHTSA EDR T&B WG 4	NTSB H-99-52 5	ATA TMC RP 1214 6	FHWA IVI-134 7	NHTSA NPRM 18029 8
General Vehicle
Ignition Status/Cycle								R
Vehicle Speed	5a			P1			T1	R

Wheel Speed		P1	T1
Longitudinal Acceleration	1a	P1	T1	R
Lateral Acceleration	1b	P1	T1	IE
Vertical/Normal Acceleration		P1	T1	IE
Maximum Delta-V				R
Yaw Rate	8		T2
Tilt/Roll Angle	7		T2	IE
Steering Angle/Wheel Position	5b	P2	T1	IE
Axle/Vehicle Load Status		O	T2
Tire Pressures/Warning Lamp			T3
Cruise Control Status		P2	T2
Odometer/Trip Distance
VIN		P1	T1
Subsystem Fault Codes/Lamps
System Voltage		P2	T2
Alternator Current
Turn Signal Status		P2	T2
Wiper Status		P2	T2
Headlight Status		P2	T2
Marker Light Status		P2	T3
School Bus Stop Lamp Stat.		P2
Horn Status			T3
Trailer Status
Cell Phone/CB Status
Radio Volume
Engine and Emissions Control
Throttle Percentage				R
Accelerator Pedal Pos.		P1	T1
Intake/Boost Pressure
Exhaust Temperature
Engine Temperature
Engine RPM		P1	T1	R
Engine Load
Detonation "knock"
Airflow (MAF, VAF, MAP)*
Fuel Consumption/Level
Fuel Pressure
Engine Retarder Status		P2	T2
Oil Pressure
PTO Status
Engine Idle Time
Transmission
Transmission Gear		P1	T1
Clutch Position
Input Shaft Speed
Inertia Brake Status
Trans. Fluid Temperature
2/4/All Wheel Drive Status
Output Shaft Speed
Brake Systems
Brake Pedal Position	5c
Service Brake Status		P1	T1	R
Emergency Brake Status		P1	T1
Trailer Brake Status		P1	T1
Air Reservoir Pressure			T3
Control Pressure
Application Pressure			T1
ABS Status	9a	P1	T1	IE
Traction Control Status	9b	P2	T2
Stability Control Status	9c	P2		IE
Brake Camber Stroke			T3
Brake Shoe/Pad Force
Brake Shoe/Pad Temp.
Brake Light Status
Brake System Faults
Safety Systems
Airbag Lamp Status			T2
Impact Sensors
Driver Airbag Deploy. Time	10a	P2	T2	R
Driver Airbag Deploy. Level	10b		T2	R
Driver Airbag Nth Stage Time	10c		T2	IE
Driver Side Airbag Deploy. Time	10d		T2	IE
Pass. Airbag Disabled	10e			IE
Pass. Airbag Deploy. Time	10f			R
Pass. Airbag Deploy. Level	10g			R
Pass. Airbag Nth Stage Time	10h			IE
Pass. Side Airbag Deploy. Time				IE
Driver Seatbelt Latch Status	3a	P1	T1	R
Driver Tensioner Status				IE
Pass. Seatbelt Latch Status	3b			IE
Pass. Tensioner Status				IE
Door Latch/Lock Status
Seat Occupancy	4			IE
Driver/Pass./Seat Position				IE
Driver/Pass. Size Detection				IE
External Elements
Time/Date/Event Time	6	P1	T1	R
Geographic Position	2
Direction of Travel		P2	T1
Ambient Temperature
Road Surface Conditions			T3
Road Surface Temperature
Other
Proximity to Objects			T3
Lane Position			T3
Distance to Intersections			T3
Driver ID
Trailer ID/VIN
Video		O	T3
Audio
Temp. of Wheel Ends
Suspension Pulse History
Driver Condition			T3
Crush Zone History

* MAF, VAF, MAP stand for Mass Air Flow, Vane Air Flow, and Manifold Absolute Pressure respectively. These are deferent sensor techniques for measuring air flow and composition into a spark-ignition engine.

Based on the listings and priorities presented in Exhibit 2.1, each parameter was ranked for its relevance and applicability for commercial vehicles to (1) crash causation and accident reconstruction analysis, (2) improving operational efficiency, and (3) driver monitoring. Each parameter was assigned a qualitative ranking based on the guidelines presented in Exhibit 2.2.

Exhibit 2.2 -Ranking Categories

0	Parameter not directly related to function
1	Optional parameters that would greatly assist in performing the function but require advanced sensor installation
2	Parameters that complement the core parameters and should be recorded when the sensor technology is installed in the vehicle
4	Core parameters necessary for performing each function

Exhibit 2.3 shows the rankings for each parameter's relevance to accident reconstruction and crash causation, operational efficiency, and driver monitoring.

Exhibit 2.3 - Relationship of Data Parameters to VDR Functions

Parameters	Accident Reconstruction/ Crash Causation	Operational Efficiency	Driver Monitoring
General Vehicle
Ignition Status/Cycle	2	0	0
Vehicle Speed	4	4	4
Wheel Speed	2	2	0
Longitudinal Acceleration	4	0	0
Lateral Acceleration	4	0	0
Vertical/Normal Acceleration	4	0	0
Maximum Delta-V	4	0	0
Yaw Rate	1	0	0
Tilt/Roll Angle	1	0	0
Steering Angle/Wheel Position	1	0	0
Axle/Vehicle Load Status	1	1	0
Tire Pressure/Warning Lamp	1	1	0
Cruise Control Status	2	2	4
Odometer/Trip Distance	2	4	4
VIN	4	4	0
Subsystem Fault Codes	0	4	0
System Voltage	2	2	0
Alternator Current	0	2	0
Turn Signal Status	2	0	0
Wiper Status	2	0	0
Headlight Status	2	0	0
Marker Light Status	2	0	0
School Bus Stop Lamp Stat.	2	0	0
Horn Status	1	0	0
Trailer Status	1	0	0
Cell Phone/CB Status	1	0	1
Radio Volume	1	0	1
Engine and Emissions Control
Throttle Percentage	0	0	0
Accelerator Pedal Pos.	4	4	2
Intake/Boost Pressure	0	2	0
Exhaust Temperature	0	2	0
Engine Temperature	0	4	0
Engine RPM	4	4	4
Engine Load	0	4	4
Detonation "knock"	0	2	0
Airflow (MAF, VAF, MAP)	0	2	0
Fuel Consumption/Level	0	4	4
Fuel Pressure	0	2	0
Engine Retarder Status	0	2	2
Oil Pressure	0	2	0
PTO Status	0	2	2
Engine Idle Time	0	4	4
Transmission
Transmission Gear	4	4	2
Clutch Position	2	0	0
Input Shaft Speed	0	0	0
Inertia Brake Status	2	2	2
Trans. Fluid Temperature	0	2	0
2/4/All Wheel Drive Status	0	0	0
Output Shaft Speed	0	0	0
Brake Systems
Brake Pedal Position	4	4	4
Service Brake Status	4	0	4
Emergency Brake Status	4	0	4
Trailer Brake Status	4	0	4
Air Reservoir Pressure	2	2	0
Control Pressure	1	0	0
Application Pressure	2	0	0
ABS Status	4	2	4
Traction Control Status	2	0	2
Stability Control Status	2	0	2
Brake Camber Stroke	1	1	0
Brake Shoe/Pad Force	1	1	0
Brake Shoe/Pad Temp.	1	1	0
Brake Light Status	2	0	0
Brake System Faults	2	4	0
Safety Systems
Airbag Lamp Status	2	0	0
Impact Sensors	1	0	0
Driver Airbag Deploy. Time	2	0	0
Driver Airbag Deploy. Level	2	0	0
Driver Airbag Nth Stage Time	2	0	0
Driver Side Airbag Deploy. Time	2	0	0
Pass. Airbag Disabled	2	0	0
Pass. Airbag Deploy. Time	2	0	0
Pass. Airbag Deploy. Level	2	0	0
Pass. Airbag Nth Stage Time	2	0	0
Pass. Side Airbag Deploy. Time	2	0	0
Driver Seatbelt Latch Status	4	0	2
Driver Seatbelt Tensioner Status	1	0	0
Pass. Seatbelt Latch Status	4	0	0
Pass. Seatbelt Tensioner Status	1	0	0
Door Latch/Lock Status	2	0	0
Seat Occupancy	2	0	0
Driver/Pass./Seat Position	1	0	0
Driver/Pass. Size Detection	1	0	0
External Elements
Time/Date	2	4	4
Geographic Position	1	1	1
Direction of Travel	1	1	1
Ambient Temperature	1	0	0
Road Surface Conditions	1	0	0
Road Surface Temperature	1	0	0
Other
Proximity to Objects	1	0	1
Driver ID	2	2	4
Trailer ID/VIN	1	1	1
Video	1	0	1
Audio	1	0	1
Temp. of Wheel Ends	1	0	0
Suspension Pulse History	1	0	0
Driver Condition	1	0	1
Crush Zone History	1	0	0

These data parameters were then categorized into the following five groups (outlined in Exhibit 2.4) based on the qualitative rankings and applicability to the three main VDR functions:

Accident Reconstruction and Crash Causation Core Data Set - These are the core data parameters necessary for performing accident reconstruction and crash causation analysis. They are typified by the data recorded in an EDR.
Accident Reconstruction and Crash Causation Advanced Data Set - These are the data parameters that would complement the core data parameters in group 1, but some of which would likely require the installation of sensors at various locations around the vehicle. This data set includes all of the core accident reconstruction and crash causation data parameters in group 1.
Operational Efficiency Core Data Set - These are the core data parameters that could be used to improve a fleet's operational efficiency. The parameters are typical of the kinds of information recorded by vehicle data loggers. The information collected is used to improve maintenance efficiency, detect and prevent possible on-road breakdowns, monitor driver performance, track goods movement, and manage fleet logistics. The parameters identified as the core operational data set would be commonly available on new model tractors and would generally not require installation of additional equipment/sensors. It should be noted that to maximize operational efficiency benefits, a VDR would most likely be equipped to record geographic position through GPS or similar technology. However, as GPS and similar technologies could be beneficial to all of the five concepts but is not necessarily required, it has been included in the discussion of advanced VDR technologies in Chapter 3.
Operational Efficiency Advanced Data Set - These are the other data parameters that a fleet could use to further improve and monitor the efficiency of a fleet. Some of these parameters may require installation of additional sensors. This data set includes all of the core operational efficiency data parameters in group 3.
Driver Monitoring Data Set - These are the data parameters that could be used to monitor driver behavior for regulation enforcement, fleet safe driver incentives, or insurance policy changes.

Exhibit 2.4 - Categorized Data Sets

(1) Accident Reconstruction and Crash Causation Core Data Set
Vehicle Speed Longitudinal Acceleration Lateral Acceleration Vertical Acceleration Maximum Delta-V VIN	Accelerator Pedal Pos. Engine RPM Transmission Gear Brake Pedal Position Service Brake Status Emergency Brake Status Trailer Brake Status	ABS Status Driver Seatbelt Latch Status Passenger Seatbelt Latch Status
(2) Accident Reconstruction and Crash Causation Advanced Data Set
All Group (1) Parameters Tractor Wheel Speeds Yaw Rate Tilt/Roll Angle Steering Angle/Wheel Position Vehicle Load Status Cruise Control Status Odometer System Voltage	Turn Signal Status Wiper Status Headlight Status Marker Light Status Engine Retarder Status Clutch Position Inertial Brake Status	Air Reservoir Pressure Application Pressure Traction Control Status Stability Control Status Brake Light Status Brake System Faults Door Latch/Lock Status Seat Occupancy
(3) Operational Efficiency Core Data Set
Vehicle Speed Odometer/Trip Distance VIN Subsystem Fault Codes Accelerator Pedal Pos.	Engine Temperature Engine RPM Engine Load Fuel Consumption Driver ID	Engine Idle Time Transmission Gear Brake Pedal Position Brake System Faults Time/Date
(4) Operational Efficiency Advanced Data Set
All Group (3) Parameters Vehicle Load (GVW) Tractor Tire Pressures Cruise Control Status System Voltage Alternator Current Intake/Boost Pressure	Exhaust Temperature Detonation "knock" Fuel Pressure Engine Retarder Status Oil Pressure PTO Status	Inertia Brake Status Transmission Fluid Temperature Air Reservoir Pressure ABS Status
(5) Driver Monitoring Data Set
Vehicle Speed Cruise Control Status Odometer/Trip Distance Accelerator Pedal Pos. Engine RPM Engine Load Fuel Consumption/Level	Engine Retarder Status PTO Status Engine Idle Time Transmission Gear Inertia Brake Status Brake Pedal Position Service Brake Status Emergency Brake Status Trailer Brake Status	ABS Status Traction Control Status Stability Control Status Seatbelt Latch Status Time/Date Driver ID

VDR Concepts

Using the government and industry findings on data parameters for VDRs along with the summary rankings presented in the previous section, the following VDR concepts were developed:

A low-cost event-triggered data recorder for recording baseline crash and severe incident data
A more advanced event-triggered data recorder that incorporates some advanced sensor technologies
A baseline continuous VDR that records maintenance and operational data meant to improve fleet operations
An advanced continuous data recorder that includes additional driver monitoring parameters
A "full-featured" VDR that may include both accident data and operational efficiency data

Each of these five concepts was mapped to the data sets developed in the previous section, as shown in Exhibit 2.5.

Exhibit 2.5 - Concept VDR Overview

Capabilities	Concept Vehicle Data Recorders
Capabilities	Concept #1	Concept #2	Concept #3	Concept #4	Concept #5
Crash Pulse Recording (high data rate before/after crash event trigger)
Continuous and Histogram Operational Data Recording (low data rate)
Accident Reconstruction Core Data Set
Accident Reconstruction/Causation Advanced Data Set
Operational Efficiency Core Data Set
Operational Efficiency Advanced Data Set
Driver Monitoring Data Set

In order to develop cost estimates for each concept (see Chapter 4), a high-level set of specifications was developed, which included the following requirements:

Data elements to be recorded
Estimated memory requirements
Input and output requirements
Internal sensor components
Data extraction requirements
Power backup requirements
Display requirements
Programming capabilities
Physical vehicle environment requirements

A requirement was placed on all five concepts that they be standalone electronic modules, separate from other electronic modules or ECUs on the vehicle. It is anticipated that for some of the concepts, it may be possible to combine their functionality within other current or future vehicle ECUs (e.g., the engine or airbag modules). This would likely yield cost reductions over a standalone system as they could potentially utilize the same I/O, microprocessor, and storage hardware. However, certain concept architectures may not be compatible with the architecture of other vehicle ECUs (i.e., it may not be cost effective to pair crash pulse recording functionality with engine control functionality within the same electronic module). Therefore, an in-depth proprietary knowledge of the different ECU designs would be necessary to understand the exact cost impacts of pairing different concept functionalities with current/future vehicle ECUs. While it is recognized that this might impact the actual cost to manufacture each concept, in order to adequately compare the relative costs between concepts, all concepts were specified as a separate electronic modules.

As noted earlier, in addition to the VDR "baseline" concepts, a listing of advanced VDR technologies that could be added to any of the five concepts was developed. These include:

Additional internal memory storage (i.e., a storage upgrade to record more data surrounding an event)
Removable storage media (i.e., magnetic, optical, solid-state memory)
Onboard vehicle network communication and downloading (e.g., CAN, IDB, serial)
Vehicle location, direction of travel, and absolute time (e.g., GPS)
Digital imaging (e.g., video)
Sensor for determining the relative location of nearby vehicles (e.g., radar, ultrasonic)
Short-range wireless communications (e.g., infrared, Bluetooth, WiFi 802.11)
Long-range wireless communications (e.g., satellite, cellular)
Driver performance (e.g., attentive driver monitoring, drowsy driver warning)
Tractor-to-trailer communications

The following subsections describe in detail each concept. The advanced VDR technologies and features are described in Chapter 3.

Concept 1 - Core Accident Event VDR

Concept 1 is a low-cost event-triggered data recorder for recording various types of onboard data that might be used to assist with accident reconstruction. It would include provisions for recording vehicle dynamics before, during, and after an event.

Most of the data would come from existing subsystem ECUs and would be available over one or more of the vehicle's communications networks (e.g., J1587 and J1939). The EDR would need to contain a three-axis accelerometer (i.e., longitudinal, lateral, vertical). It will also be necessary to have four digital inputs (on/off) to record emergency brake, trailer brake, driver seatbelt latch, and passenger seatbelt latch status. Two analog sensor inputs will be required for accelerator and brake pedal position sensors. Because Concept 1 would be designed to record data both before and after an accident event, it will require an internal backup power supply that would enable the EDR to record data for the short period immediately following an accident should the vehicle main battery be disabled. Exhibit 2.6 details the data elements which would be included in Concept 1, along with the storage algorithm (e.g., time triggered history, histogram, single value, etc.), units, possible data sources, and possible input sources (e.g., J1939, J1708, analog input, digital input, etc.).

Exhibit 2.6 - Concept 1 Standard Data Elements

Data Element	Storage Algorithm	Unit	Data Sources	Input Source
Accident Reconstruction and Crash Causation Core Data Set
ABS Status	Triggered Time History	On/Off/Active	ABS ECU	J1939/J1708
Acceleration - Lateral	Triggered Time History	ft/sec/sec	Accelerometer	Internal Analog Accelerometer
Acceleration - Longitudinal	Triggered Time History	ft/sec/sec	Accelerometer	Internal Analog Accelerometer
Acceleration - Vertical	Triggered Time History	ft/sec/sec	Accelerometer	Internal Analog Accelerometer
Accelerator Pedal Position	Triggered Time History	%	Pedal Position Sensor	Analog Sensor Input
Brake Pedal Position	Triggered Time History	%	Pedal Position Sensor	Analog Sensor Input
Driver Seatbelt Latch Status	Triggered Time History	On/Off	Latch Sensor	Digital Sensor Input
Emergency Brake Status	Triggered Time History	On/Off	Switch Sensor	Digital Sensor Input
Engine RPM	Triggered Time History	rpm	Engine ECU	J1939/J1708
Maximum Delta-V	Single Triggered Value	ft/sec/sec	Accelerometer	Internal Analog Accelerometer
Passenger Seatbelt Latch Status	Triggered Time History	On/Off	Latch Sensor	Digital Sensor Input
Service Brake Status	Triggered Time History	On/Off	ABS ECU	J1939/J1708
Trailer Brake Status	Triggered Time History	On/Off	Switch Sensor	Digital Sensor Input
Transmission Gear	Triggered Time History	Numeric	Transmission ECU	J1939/J1708
Vehicle Speed	Triggered Time History	ft/sec	Transmission ECU, ABS ECU	J1939/J1708
VIN	Single Most Recent Value	Alphanumeric	Engine/Vehicle ECU	J1939/J1708

Exhibit 2.7 shows an estimate of the memory requirements for storing the data elements in Exhibit 2.6. This estimate was developed to provide a rough basis for determining the cost associated with each concept. It is a raw memory size estimate, and does not include the anticipated overhead needed to store the programming, file structures, or other needed information in the VDR.

Exhibit 2.7 - Concept 1 Estimated Memory Requirements

Data Element	Resolution	Field Size (bytes)	Frequency (Hz)	Recording Duration (sec)	Raw Record Size (bits)
Accident Reconstruction and Crash Causation Core Data Set
ABS Status	On/Off	1	10	20	1600
Acceleration - Lateral	High	8	1,000	5	320,000
Acceleration - Longitudinal	High	8	1,000	5	320,000
Acceleration - Vertical	High	8	1,000	5	320,000
Accelerator Pedal Position	Low	4	10	20	6,400
Brake Pedal Position	Low	4	10	20	6,400
Driver Seatbelt Latch Status	On/Off	1	10	20	1,600
Emergency Brake Status	On/Off	1	10	20	1,600
Engine RPM	Low	4	10	20	6,400
Maximum Delta V	High	8			64
Passenger Seatbelt Latch Status	On/Off	1	10	20	1,600
Service Brake Status	On/Off	1	10	20	1,600
Trailer Brake Status	On/Off	1	10	20	1,600
Transmission Gear	Low	4	10	20	6,400
Vehicle Speed	Low	4	10	20	6,400
VIN	String	17			136
Total Raw Record Size (bits)					1,001,800

Input/Output (I/O) Requirements

The following inputs will be required:

Four digital sensor inputs
Two analog sensor inputs

No outputs will be required.

The following vehicle network I/O transceivers will be required:

J1939
J1708
RS-232 (for downloading of data and programming of EDR)

Internal Sensor Components

The following sensor components will be required to be internal to the recorder:

Three-axis (i.e., longitudinal, lateral, vertical) high-resolution, high-frequency accelerometer (similar to those used in light-duty airbag modules)

Data Extraction requirements

Data would be formatted and downloadable via RS-232.

Power Backup Requirements

Power should be maintained for a minimum of 10 seconds after an event to continue to record data, and for the additional time necessary to properly store this data permanently to prevent data loss or corruption.

Displays

None.

Programming Capabilities

The EDR should have basic programming capabilities to allow OEMs to program specific event triggers (based upon available inputs) and recording durations (before/after trigger). This could be performed over the RS-232 port or J1939/J1708. This capability would not be available to the operator/purchaser of the vehicle.

Other Requirements

The system would be contained within a separate electronic module. The module should have impact, heat, and other mechanical design specs similar to other electronic modules that would be mounted within the driver compartment (i.e., SAE J1455 for driver compartment mounted components).
All processing of data would be done post-downloading during accident reconstruction (data would need to be simply recorded in a pre-defined location).
Should be able to record up to two (2) events.
Recording trigger would be based on exceeding preset deceleration rate or delta-V.
All components will be selected to meet heavy-duty vehicle Class 6, 7, and 8 NVH standards (i.e., SAE J1455 for driver compartment-mounted components).

Concept 2 - Advanced Accident Event VDR with Advanced Vehicle Sensors

In addition to including all of the capabilities of Concept 1, Concept 2 would incorporate some advanced sensor technology and additional data elements for accident reconstruction and crash causation. Concept 2 is primarily intended to provide all of the necessary data for determining vehicle dynamics and driver inputs during an accident event, and would therefore likely require several additional sensors not normally found on a commercial vehicle, including yaw rate, tilt, steering wheel position, and vehicle/axle load sensors. Additionally, Concept 2 would record the status of most vehicle subsystems (e.g., lights, retarder, inertia brake , traction control, stability control, and airbag). Like Concept 1, Concept 2 would mostly record high-resolution data shortly before and after an event, along with some key information stamped at the time of the trigger (e.g., odometer, vehicle load).

Concept 2 will not only require fast data-processing capabilities, it will also require a larger storage capacity to accommodate both the core and advanced accident reconstruction data sets. Like Concept 1, Concept 2 would have an internal backup power supply to allow recording of data after an accident event should the main battery power be disabled.

Exhibit 2.8 details Concept 2 individual data elements along with each element's storage algorithm, units, data source, and input source.

Exhibit 2.8 - Concept 2 Standard Data Elements

Data Element	Storage Algorithm	Unit	Data Sources		Input Source
Accident Reconstruction and Crash Causation Core Data Set (Concept 1 Data Elements)
See Concept 1				1,001,800
Accident Reconstruction and Crash Causation Advanced Data Set
Air Reservoir Pressure	Triggered Time History	PSI	Pressure Sensor, ABS ECU		Analog Sensor Input
Application Pressure	Triggered Time History	PSI	Pressure Sensor, ABS ECU		Analog Sensor Input
Brake Light Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU		J1939/J1708
Brake System Faults	Single Triggered Value	Alphanumeric	ABS ECU		J1939/J1708
Clutch Position	Triggered Time History	On/Off	Transmission ECU, Clutch Sensor		J1939/J1708
Cruise Control Status	Triggered Time History	On/Off	Engine/Vehicle ECU, Switch Sensor		J1939/J1708
Door Latch/Lock Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU		Digital Sensor Input
Engine Retarder Status	Triggered Time History	On/Off	Engine ECU		J1939/J1708
Headlight Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU		J1939/J1708
Inertia Brake Status	Triggered Time History	On/Off	Transmission ECU		J1939/J1708
Marker Light Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU		J1939/J1708
Odometer	Single Triggered Value	Numeric	Engine/Vehicle ECU		J1939/J1708
Seat Occupancy	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU, ABS ECU		Digital Sensor Input
Stability Control System Status	Triggered Time History	On/Off/Active	ABS ECU		J1939/J1708
Steering Angle/Wheel Position	Triggered Time History	deg	Steering Wheel Position Sensor		Analog Sensor Input
System Voltage	Triggered Time History	volts	Engine ECU, Vehicle/Dash ECU		J1939/J1708
Tilt/Roll Angle	Triggered Time History	deg	Tilt Sensor		Internal Tilt Sensor
Traction Control System Status	Triggered Time History	On/Off/Active	ABS ECU		J1939/J1708
Tractor Wheel Speeds	Triggered Time History	ft/sec	ABS ECU		J1939
Turn Signal Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU		J1939/J1708
Vehicle Load (GVW)	Single Triggered Value	lbs	Axle Load Sensors		Analog Sensor Input
Wiper Status	Triggered Time History	On/Off	Vehicle/Dash ECU, Switch Sensor		J1939/J1708
Yaw Rate	Triggered Time History	deg/sec	Yaw Sensor		Internal Yaw Sensor

Exhibit 2.9 shows an estimate of the memory requirements for storing the data elements in Exhibit 2.8. As with the memory estimates for Concept 1, this estimate was developed to provide a rough basis for determining the cost associated with each concept. It is a raw memory size estimate, and does not include the anticipated overhead needed to store the programming, file structures, or other needed information in the VDR.

Exhibit 2.9 - Concept 2 Estimated Memory Requirements

Data Element	Resolution	Field Size (bytes)	Frequency (Hz)	Recording Duration (sec)	Raw Record Size (bits)
Accident Reconstruction and Crash Causation Core Data Set (Concept 1 Data Elements)
See Concept 1
Accident Reconstruction and Crash Causation Advanced Data Set
Air Reservoir Pressure	Low	4	10	20	6,400
Application Pressure	Low	4	10	20	6,400
Brake Light Status	On/Off	1	10	20	1,600
Brake System Faults	String	100			800
Clutch Position	Low	4	10	20	6,400
Cruise Control Status	On/Off	1	10	20	1,600
Door Latch/Lock Status	On/Off	1	10	20	1,600
Engine Retarder Status	On/Off	1	10	20	1,600
Headlight Status	On/Off	1	10	20	1,600
Inertia Brake Status	On/Off	1	10	20	1,600
Marker Light Status	On/Off	1	10	20	1,600
Odometer	Low	4			32
Seat Occupancy	On/Off	1	10	20	1,600
Stability Control System Status	On/Off	1	10	20	1,600
Steering Angle/Wheel Position	Low	4	10	20	6,400
System Voltage	Low	4	10	20	6,400
Tilt/Roll Angle	High	8	1,000	5	320,000
Traction Control System Status	On/Off	1	10	20	1,600
Tractor Wheel Speeds (6)	Low	24	10	20	4,800
Turn Signal Status	On/Off	1	10	20	1,600
Vehicle Load (GVW)	Low	4			32
Wiper Status	On/Off	1	10	20	1,600
Yaw Rate	High	8	1,000	5	320,000
Total Raw Record Size (bits)					1,693,864

I/O Requirements

The following inputs will be required:

Six digital sensor inputs
Six analog sensor inputs

No outputs will be required.

The following vehicle network I/O transceivers will be required:

J1939
J1708
RS-232 (for downloading of data and programming of EDR)

Internal Sensor Components

The following sensor components will be required to be internal to the recorder:

Three-axis (i.e., longitudinal, lateral, vertical) high-resolution, high-frequency accelerometer (similar to those used in light-duty airbag modules)
Yaw rate sensor - high resolution, high frequency
Tilt/roll angle sensor - high resolution, high frequency

Data Extraction requirements

Data would be formatted and downloadable via RS-232.

Power Backup Requirements

Displays

None.

Programming Capabilities

Other Requirements

The system would be contained within a separate electronic module. The module should have impact, heat, and other mechanical design specs similar to other electronic modules that would be mounted within the driver compartment (i.e., SAE J1455 for driver compartment mounted components).
All processing of data would be done post-downloading during accident reconstruction (data would need to be simply recorded in a pre-defined location).
Should be able to record up to two (2) events.
Recording trigger would be based on exceeding preset deceleration rate or delta-V.
All components will be selected to meet heavy-duty vehicle Class 6, 7, and 8 NVH standards (i.e., SAE J1455 for driver compartment mounted components).

Concept 3 - Core Operational Efficiency VDR

Concept 3 is a "continuous" VDR that records a variety of operating data that can be used for improving maintenance planning (predictive maintenance) and for monitoring driver performance and operations. It would include only a core operational efficiency data set to provide basic measures of vehicle/fleet efficiency. To this end, both summary data (minimums, maximums, averages, cumulative totals) and histogram data (segmented data categorized in various "bins") would be recorded for a variety of channels.

The modest parameter set and storage algorithm requirements result in a VDR with a small storage capacity, and would likely not require a fast processing capability as only summary-type data are recorded at a much slower frequency than that of Concept 1 (EDR). Additionally, all of the data elements should be available over one of the vehicle networks (J1587/J1939) from either the engine, transmission, or ABS ECUs. It may be necessary, however, for Concept 3 to have two analog inputs for the accelerator pedal position and brake pedal position if these data are not available over either databus. In practice, this type of VDR functionality is made available as an option by engine manufacturers using the engine ECU as the recording and processing device.

Concept 3 would also require a methodology for recording driver identification. This would require either manual driver inputs of driver ID or an automated system that can keep track of driver IDs. Exhibit 2.10 details Concept 3 individual data elements.

Exhibit 2.10 - Concept 3 Standard Data Elements

Data Element	Storage Algorithm	Unit	Data Sources	Input Source
Operational Efficiency Core Data Set
Accelerator Pedal Position	Histogram, Max, Min, Average	%	Pedal Position Sensor	Analog Sensor Input
Brake Pedal Position	Histogram, Max, Min, Average	%	Pedal Position Sensor	Analog Sensor Input
Brake System Faults	Single Most Recent Value	Alphanumeric	ABS ECU	J1939/J1708
Driver ID	Time History of Driver ID	Alphanumeric Driver ID	SmartCard Reader, TWIC Reader, Driver ID Keyboard	RS-232
Engine Idle Time	Cumulative	h-m-s	Engine ECU	J1939/J1708
Engine Load	Histogram, Max, Min, Average	%	Engine ECU	J1939/J1708
Engine RPM	Histogram, Max, Min, Average	rpm	Engine ECU	J1939/J1708
Engine Temperature	Histogram, Max, Min, Average	degrees F	Engine ECU	J1939/J1708
Fuel Consumption	Average	mpg	Engine ECU	J1939/J1708
Odometer/Trip Distance	Single Most Recent Value	Numeric	Engine ECU, Vehicle/Dash ECU	J1939/J1708
Subsystem Fault Codes	Single Most Recent Value	Alphanumeric	All ECUs	J1939/J1708
Time/Date	Single Most Recent Value	mm/dd/yyyy h-m-s	VDR Internal Clock	Internal Clock
Transmission Gear	Histogram	Numeric	Transmission ECU	J1939/J1708
Vehicle Speed	Histogram, Max, Min, Average	ft/sec	Transmission ECU, ABS ECU	J1939/J1708
VIN	Single Most Recent Value	Alphanumeric	Engine ECU, Vehicle/Dash ECU	J1939/J1708

Exhibit 2.11 shows an estimate of the memory requirements for storing the data elements in Exhibit 2.10.

Exhibit 2.11 - Concept 3 Estimated Memory Requirements

Data Element	Record Type/ Resolution	Field Size (bytes)	Frequency (Hz)	Recording Duration (sec)	Raw Record Size (bits)
Operational Efficiency Core Data Set
Accelerator Pedal Position	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Brake Pedal Position	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Brake System Faults	Alphanumeric String	100			800
Driver ID	Time History of Driver ID (1/60 Hz, 1 Week Duration) - Low	4			322,560
Engine Idle Time	Cumulative	4			32
Engine Load	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Engine RPM	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Engine Temperature	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Fuel Consumption/Level	Low	4			32
Odometer/Trip Distance	Low	4			32
Subsystem Fault Codes	Alphanumeric String	100			800
Time/Date	Low	4			32
Transmission Gear	Histogram - Low	40			320
Vehicle Speed	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
VIN	Alphanumeric String	17			136
Total Raw Record Size (bits)					327,904

I/O Requirements

The following inputs will be required:

Two analog sensor inputs
RS-232 (for interfacing with driver ID recording device)

No outputs will be required.

The following vehicle network I/O transceivers will be required:

J1939
J1708
RS-232 (for downloading of data and programming of VDR)

Internal Sensor Components

The following sensor components will be required to be internal to the recorder:

Internal clock to record mm/dd/yyyy h-m-s.sss

Driver ID Recording

The VDR will record a driver's ID if and when a driver ID is entered by means of a variety of devices (e.g., SmartCard reader, TWIC card reader, and keyboard) that connect to the VDR via the RS-232 input. The VDR will then keep a time history record of the driver ID when the vehicle is running and in motion (i.e., in service).

Data Extraction requirements

Data would be formatted and downloadable via RS-232.

Power Backup Requirements

No specific power backup is required. The system should maintain enough power or be designed so that data is not corrupted in the event of a loss of power or voltage spike.

Displays

None.

Programming Capabilities

The VDR should have basic programming capabilities to allow fleets, OEMs, and operators to program the type of summary trip activity information recorded (e.g., averages, minimum and maximum thresholds). This could be performed over the RS-232 port or J1939/J1708. This capability would be available to the operator of the vehicle.

Other Requirements

The system would be contained within a separate electronic module. The module should have impact, heat, and other mechanical design specs similar to other electronic modules that would be mounted within the driver compartment (i.e., SAE J1455 for driver compartment mounted components).
All components will be selected to meet heavy-duty vehicle Class 6, 7, and 8 NVH standards (i.e., SAE J1455 for driver compartment mounted components).

Concept 4 - Advanced Operational Efficiency and Driver Monitoring VDR

Concept 4 would be a comprehensive VDR for improving driver, vehicle, and fleet operational efficiency and for driver monitoring. The concept would include provisions for recording data elements needed to provide fleet managers and maintenance personnel with a detailed picture of both the driver's and vehicle's performance. Concept 4 would record both summary and histogram data on almost every critical vehicle subsystem along with driver behavioral sensors (e.g., seatbelt latch, maximum vehicle speeds, maximum engine RPM). Most of these parameters are available over one of the vehicle networks (J1587, J1939), so a limited number of additional sensors would be required, including:

Axle or vehicle load sensors
Tire pressure monitoring sensors
Emergency brake status switch sensor (if not already installed)
Trailer brake status switch sensor (if not already installed)
Seatbelt latch sensor (if not already installed)

Concept 4, like Concept 3, would require a methodology for recording driver identification, either through manual driver inputs of driver ID or an automated system that can keep track of driver IDs. Concept 4 also includes tractor tire pressure data elements, and the sensors and systems needed to accomplish this.

Exhibit 2.12 details the Concept 4 individual data elements along with each element's storage algorithm, units, record type, and possible sources.

Exhibit 2.12 - Concept 4 Standard Data Elements

Data Element	Storage Algorithm	Unit	Data Sources		Input Source
Operational Efficiency Core Data Set (Concept 3 Data Elements)
See Concept 3				327,904
Operational Efficiency Advanced Data Set and Driver Monitoring Data Set
ABS Status	Histogram	On/Off/Active	ABS ECU		J1939/J1708
Air Reservoir Pressure	Histogram, Max, Min, Average	PSI	ABS ECU, Pressure Transducer		Analog Sensor Input
Alternator Current	Histogram, Max, Min, Average	amps	Engine ECU, Vehicle/Dash ECU		J1939/J1708
Cruise Control Status	Histogram	On/Off	Engine ECU, Vehicle/Dash ECU, Switch Sensor		J1939/J1708
Detonation "knock"	Histogram	On/Off	Engine ECU		J1939/J1708
Driver Seatbelt Latch Status	Histogram	On/Off	Latch Sensor		J1939/J1708
Emergency Brake Status	Histogram	On/Off	Switch Sensor		Digital Sensor Input
Engine Retarder Status	Histogram	On/Off	Engine ECU		J1939/J1708
Exhaust Temperature	Histogram, Max, Min, Average	degrees F	Engine ECU		J1939/J1708
Fuel Pressure	Histogram, Max, Min, Average	PSI	Engine ECU		J1939/J1708
Inertia Brake Status	Histogram, Cumulative	On/Off	Transmission ECU		J1939/J1708
Intake/Boost Pressure	Histogram, Max, Min, Average	PSI	Engine ECU		J1939/J1708
Oil Pressure	Histogram, Max, Min, Average	PSI	Engine ECU		J1939/J1708
PTO Status	Histogram	h-m-s	Engine ECU, Transmission ECU		J1939/J1708
Service Brake Status	Histogram	On/Off	ABS ECU		J1939/J1708
Stability Control System Status	Histogram	On/Off/Active	ABS ECU		J1939/J1708
System Voltage	Histogram, Max, Min, Average	volts	Engine ECU, Vehicle/Dash ECU		J1939/J1708
Traction Control System Status	Histogram	On/Off/Active	ABS ECU		J1939/J1708
Tractor Tire Pressures (10)	Histogram, Max, Min, Average	PSI	Tire Pressure Monitoring System		J1939
Trailer Brake Status	Histogram	On/Off	Switch Sensor		Digital Sensor Status
Transmission Fluid Temperature	Histogram, Max, Min, Average	degrees F	Transmission ECU		J1939/J1708
Vehicle Load (GVW)	Histogram, Max, Min, Average	lbs	Axle Load Sensors		Analog Sensor Input

Exhibit 2.13 shows an estimate of the memory requirements for storing the data elements in Exhibit 2.12.

Exhibit 2.13 - Concept 4 Estimated Memory Requirements

Data Element	Record Type/ Resolution	Field Size (bytes)	Frequency (Hz)	Recording Duration (sec)	Raw Record Size (bits)
Operational Efficiency Core Data Set (Concept 3 Data Elements)
See Concept 3
Operational Efficiency Advanced Data Set and Driver Monitoring Data Set
ABS Status	Histogram - Low	40			320
Air Reservoir Pressure	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Alternator Current	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Cruise Control Status	Histogram - On/Off	10			320
Detonation "knock"	Histogram - Low	40			320
Driver Seatbelt Latch Status	Histogram - On/Off	10			320
Emergency Brake Status	Histogram - On/Off	10			320
Engine Retarder Status	Histogram - On/Off	10			320
Exhaust Temperature	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Fuel Pressure	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Inertia Brake Status	Histogram - On/Off	10			320
Intake/Boost Pressure	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Oil Pressure	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
PTO Status	Cumulative - Low	4			32
Service Brake Status	Histogram - On/Off	10			320
Stability Control System Status	Histogram - On/Off	10			320
System Voltage	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Traction Control System Status	Histogram - On/Off	10			320
Tractor Tire Pressures (10 tires )	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	400 40 40 40			3,200 320 320 320
Trailer Brake Status	Histogram - On/Off	10			320
Transmission Fluid Temperature	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Vehicle Load (GVW)	Histogram - Low Min Value - Low Max Value - Low Ave Value - Low	40 4 4 4			320 32 32 32
Total Raw Record Size (bits)					339,360

I/O Requirements

The following inputs will be required:

Four analog sensor inputs
Two digital sensor inputs
RS-232 (for interfacing with driver ID recording device)

No outputs will be required.

The following vehicle network I/O transceivers will be required:

J1939
J1708
RS-232 (for downloading of data and programming of VDR)

Internal Sensor Components

The following sensor components will be required to be internal to the recorder:

Internal clock to record mm/dd/yyyy h-m-s.sss

Driver ID Recording

The VDR will record a driver's ID if/when a driver ID is entered by means of a variety of devices (e.g., SmartCard reader, TWIC card reader, keyboard) that connect to the VDR via the RS-232 input. The VDR will then keep a time history record of the driver ID when the vehicle is running and in motion (i.e., in service).

Data Extraction requirements

Data would be formatted and downloadable via RS-232.

Power Backup Requirements

No specific power backup will be required. The system should maintain enough power or be designed so that data is not corrupted in the event of a loss of power or voltage spike.

Displays

None.

Programming Capabilities

Other Requirements

The system would be contained within a separate electronic module. The module should have impact, heat, and other mechanical design specs similar to other electronic modules that would be mounted within the driver compartment (i.e., SAE J1455 for driver compartment mounted components).
All components will be selected to meet heavy-duty vehicle Class 6, 7, and 8 NVH standards (i.e., SAE J1455 for driver compartment mounted components).

Concept 5 - "Full-Featured" Accident Event, Operational Efficiency, and Driver Monitoring VDR

Concept 5 is a "full-featured" VDR/EDR and combines advanced accident reconstruction data set with advanced operational efficiency and driver monitoring data set. It is not only designed to record high-resolution data before, during, and after an accident event, but also to continuously record histogram and summary data to improve fleet efficiency, fleet maintenance, and monitor driver performance. This recorder would therefore require several added internal sensors (three-axis accelerometer, yaw rate, tile/roll angle) and several inputs for additional sensors not normally found on a commercial vehicle (steering wheel position, tire pressure monitoring, and vehicle/axle load). Additionally, this recorder would record the status of most vehicle subsystems (e.g., lights, retarder, inertia brake, traction control, stability control, airbag).

This recorder would record an extensive amount of data and, therefore, would require significant storage capacity. Additionally, because it would be recording data at a high frequency before and after an event trigger, it will require a fast data-processing capability and an internal backup power supply. The extensive list of data elements means that Concept 5 would require six analog and five digital inputs to record data that is not available on the vehicle's databuses (J1587/J1939). Exhibit 2.14 details the data elements for Concept 5.

Exhibit 2.14 - Concept 5 Standard Data Elements

Data Element	Storage Algorithm	Unit	Data Sources	Input Source
Accident Reconstruction and Crash Causation Core Data Set Accident Reconstruction and Crash Causation Advanced Data Set Operational Efficiency Core Data Set Operational Efficiency Advanced Data Set Driver Monitoring Data Set
ABS Status	Triggered Time History, Histogram	On/Off/Active	ABS ECU	J1939/J1708
Acceleration - Lateral	Triggered Time History	ft/sec/sec	Accelerometer, Airbag ECU	Internal Analog Accelerometer
Acceleration - Longitudinal	Triggered Time History	ft/sec/sec	Accelerometer, Airbag ECU	Internal Analog Accelerometer
Acceleration - Vertical	Triggered Time History	ft/sec/sec	Accelerometer, Airbag ECU	Internal Analog Accelerometer
Accelerator Pedal Position	Triggered Time History, Histogram, Max, Min, Average	%	Pedal Position Sensor	Analog Sensor Input
Air Reservoir Pressure	Triggered Time History, Histogram, Max, Min, Average	PSI	Pressure Sensor, ABS ECU	Analog Sensor Input
Alternator Current	Histogram, Max, Min, Average	amps	Engine ECU, Vehicle/Dash ECU	J1939/J1708
Application Pressure	Triggered Time History	PSI	Pressure Sensor, ABS ECU	Analog Sensor Input
Brake Light Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	J1939/J1708
Brake Pedal Position	Triggered Time History, Histogram, Max, Min, Average	%	Pedal Position Sensor	Analog Sensor Input
Brake System Faults	Single Triggered Value, Single Most Recent Value,	Alphanumeric	ABS ECU	J1939/J1708
Clutch Position	Triggered Time History	On/Off	Transmission ECU, Clutch Sensor	J1939/J1708
Cruise Control Status	Triggered Time History, Histogram	On/Off	Engine/Vehicle ECU, Switch Sensor	J1939/J1708
Detonation "knock"	Histogram	On/Off	Engine ECU	J1939/J1708
Door Latch/Lock Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	Digital Sensor Input
Driver ID	Time History of Driver ID	Alphanumeric Driver ID	SmartCard Reader, TWIC Reader, Driver ID Keyboard	RS-232
Driver Seatbelt Latch Status	Triggered Time History, Histogram	On/Off	Latch Sensor	J1939/J1708
Emergency Brake Status	Triggered Time History, Histogram	On/Off	Switch Sensor	Digital Sensor Input
Engine Idle Time	Cumulative	h-m-s	Engine ECU	J1939/J1708
Engine Load	Histogram, Max, Min, Average	%	Engine ECU	J1939/J1708
Engine Retarder Status	Triggered Time History, Histogram, Cumulative	On/Off	Engine ECU	J1939/J1708
Engine RPM	Triggered Time History, Triggered Time History, Histogram, Max, Min, Average	rpm	Engine ECU	J1939/J1708
Engine Temperature	Histogram, Max, Min, Average	degrees F	Engine ECU	J1939/J1708
Exhaust Temperature	Histogram, Max, Min, Average	degrees F	Engine ECU	J1939/J1708
Fuel Consumption/ Level	Histogram, Max, Min, Average	mpg	Engine ECU	J1939/J1708
Fuel Pressure	Histogram, Max, Min, Average	PSI	Engine ECU	J1939/J1708
Headlight Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	J1939/J1708
Inertia Brake Status	Triggered Time History, Histogram	On/Off	Transmission ECU	J1939/J1708
Intake/Boost Pressure	Histogram, Max, Min, Average	PSI	Engine ECU	J1939/J1708
Marker Light Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	J1939/J1708
Maximum Delta-V	Single Triggered Value	ft/sec/sec	Accelerometer, Airbag ECU	Internal Analog Accelerometer
Odometer	Single Triggered Value Single Current Value	Numeric	Engine/Vehicle ECU	J1939/J1708
Oil Pressure	Histogram, Max, Min, Average	PSI	Engine ECU	J1939/J1708
Passenger Seatbelt Latch Status	Triggered Time History	On/Off	Latch Sensor	J1939/J1708
PTO Status	Cumulative	h-m-s	Engine ECU, Transmission ECU	J1939/J1708

Seat Occupancy	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU, ABS ECU	Digital Sensor Input
Service Brake Status	Triggered Time History, Histogram	On/Off	ABS ECU,	J1939/J1708
Stability Control System Status	Triggered Time History, Histogram	On/Off/Active	ABS ECU	J1939/J1708
Steering Angle / Wheel Position	Triggered Time History	deg	Steering Wheel Position Sensor	Analog Sensor Input
Subsystem Fault Codes	Single Current Value	Alphanumeric	All ECUs	J1939/J1708
System Voltage	Triggered Time History, Histogram, Max, Min, Average	volts	Engine ECU, Vehicle/Dash ECU	J1939/J1708
Tilt/Roll Angle	Triggered Time History	deg	Tilt Sensor	Internal Tilt Sensor
Time/Date	Single Triggered Value Single Current Value	mm/dd/yyyy h-m-s	VDR Internal Clock	Internal Clock
Traction Control System Status	Triggered Time History, Histogram	On/Off/Active	ABS ECU	J1939/J1708
Tractor Tire Pressures (10)	Histogram, Max, Min, Average	PSI	Tire Pressure Monitoring System	J1939
Tractor Wheel Speeds (6)	Triggered Time History	ft/sec	ABS ECU	J1939
Trailer Brake Status	Triggered Time History, Histogram	On/Off	Switch Sensor	Digital Sensor Input
Transmission Fluid Temperature	Histogram, Max, Min, Average	degrees F	Transmission ECU	J1939/J1708
Transmission Gear	Triggered Time History, Histogram	Numeric	Transmission ECU	J1939/J1708
Turn Signal Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	J1939/J1708
Vehicle Load (GVW)	Single Triggered Value, Histogram, Max, Min, Average	lbs	Axle Load Sensors	Analog Sensor Input
Vehicle Speed	Triggered Time History, Histogram, Max, Min, Average	ft/sec	Transmission ECU, ABS ECU	J1939/J1708
VIN	Single Most Recent Value	Alphanumeric	Engine/Vehicle ECU	J1939/J1708
Wiper Status	Triggered Time History	On/Off	Switch Sensor, Vehicle/Dash ECU	J1939/J1708
Yaw Rate	Triggered Time History	deg/sec	Yaw Sensor	Internal Yaw Sensor

Exhibit 2.15 shows an estimate of the memory requirements for storing the data elements in Exhibit 2.14.

Exhibit 2.15 - Concept 5 Estimated Memory Requirements

Data Element	Resolution	Field Size (bytes)	Frequency (Hz)	Recording Duration (sec)	Raw Record Size (bits)
ABS Status	Triggered Time History - Low Histogram - Low	4 40	10	20	6,400 320
Acceleration - Lateral	Triggered Time History - High	8	1,000	5	320,000
Acceleration - Longitudinal	Triggered Time History - High	8	1,000	5	320,000
Acceleration - Vertical	Triggered Time History - High	8	1,000	5	320,000

Accelerator Pedal Position	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
Air Reservoir Pressure	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
Alternator Current	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Application Pressure	Triggered Time History - Low	4	10	20	6,400
Brake Light Status	Triggered Time History - On/Off	1	10	20	1,600
Brake Pedal Position	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
Brake System Faults	Single Triggered Value - String Single Most Recent Value - String	100 100			800 800
Clutch Position	Triggered Time History - Low	4	10	20	6,400
Cruise Control Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Detonation "knock"	Histogram - Low	40			320
Door Latch/Lock Status	Triggered Time History - On/Off	1	10	20	1,600
Driver ID	Time History of Driver ID- Low	4	1/60	604,800	322,560
Driver Seatbelt Latch Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Emergency Brake Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Engine Idle Time	Cumulative - Low	4			32
Engine Load	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Engine Retarder Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Engine RPM	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
Engine Temperature	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Exhaust Temperature	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Fuel Consumption/ Level	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Fuel Pressure	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Headlight Status	Triggered Time History - On/Off	1	10	20	1,600
Inertia Brake Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Intake/Boost Pressure	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Marker Light Status	Triggered Time History - On/Off	1	10	20	1,600
Maximum Delta-V	Single Triggered Value - High	8			64
Odometer	Single Triggered Value - Low Single Current Value - Low	4 4			32 32
Oil Pressure	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Passenger Seatbelt Latch Status	Triggered Time History - On/Off	1	10	20	1,600
PTO Status	Cumulative - Low	4			32
Seat Occupancy	Triggered Time History - On/Off	1	10	20	1,600
Service Brake Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Stability Control System Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Steering Angle/Wheel Position	Triggered Time History - Low	4	10	20	6,400
Subsystem Fault Codes	Single Current Value - String	100			800
System Voltage	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
Tilt/Roll Angle	Triggered Time History - High	8	1000	5	320,000
Time/Date	Single Triggered Value - Low Single Current Value - Low	4 4			32 32
Traction Control System Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80
Tractor Tire Pressures (10)	Histogram - Low Max - Low Min - Low Average - Low	400 40 40 40			3,200 320 320 320
Tractor Wheel Speeds (6)	Triggered Time History - Low	24	10	20	4,800
Trailer Brake Status	Triggered Time History - On/Off Histogram - On/Off	1 10	10	20	1,600 80

Transmission Fluid Temperature	Histogram - Low Max - Low Min - Low Average - Low	40 4 4 4			320 32 32 32
Transmission Gear	Triggered Time History - Low Histogram - Low	4 40	10	20	6,400 320
Turn Signal Status	Triggered Time History - On/Off	1	10	20	1,600
Vehicle Load (GVW)	Single Triggered Value - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4			32 320 32 32 32
Vehicle Speed	Triggered Time History - Low Histogram - Low Max - Low Min - Low Average - Low	4 40 4 4 4	10	20	6,400 320 32 32 32
VIN	Single Most Recent Value - String	17			136
Wiper Status	Triggered Time History - On/Off	1	10	20	1,600
Yaw Rate	Triggered Time History - High	8	1000	5	320,000
Total Raw Record Size (bits)					2,040,280

I/O Requirements

The following inputs will be required:

Six analog sensor inputs
Five digital sensor inputs
RS-232 (for interfacing with driver ID recording device)

No outputs will be required.

The following vehicle network I/O transceivers will be required:

J1939
J1708
RS-232 (for downloading of data and programming of VDR)

Internal Sensor Components

The following sensor components will be required to be internal to the recorder:

Three-axis (i.e., longitudinal, lateral, vertical) high-resolution, high-frequency accelerometer
Yaw rate sensor - high resolution, high frequency
Tilt/roll angle sensor - high resolution, high frequency
Internal clock to record mm/dd/yyyy h-m-s.sss

Driver ID Recording

Data Extraction requirements

Data would be formatted and downloadable via RS-232.

Power Backup Requirements

Displays

None.

Programming Capabilities

The VDR should have basic programming capabilities to allow fleets and OEMs to program specific event triggers (based upon available inputs) and recording durations (before/after trigger), along with the type of summary trip activity information recorded (e.g., averages, minimum and maximum thresholds). This could be performed over the RS-232 port or J1939/J1708. Event programming capability would not be available to the operator of the vehicle, while trip activity information programming could be available to the operator.

Other Requirements

The system would be contained within a separate electronic module. The module should have impact, heat, and other mechanical design specs similar to other electronic modules that would be mounted within the driver compartment (i.e., SAE J1455 for driver compartment mounted components).
All processing of data would be done post-downloading during accident reconstruction (data would need to be simply recorded in a pre-defined location).
Should be able to record up to two (2) events.
Recording trigger would be based on exceeding preset deceleration rate or delta-V.
All components will be selected to meet heavy-duty vehicle Class 6, 7, and 8 NVH standards (i.e., SAE J1455 for driver compartment mounted components).

Foot Notes

National Highway Transportation Safety Administration, Event Data Recorders - Summary of Findings, NHTSA EDR Working Group. NHTSA-99-5218-9, Washington, DC, 2001.

National Highway Transportation Safety Administration, Event Data Recorders - Summary of Findings: Volume II Supplemental Findings for Trucks, Motorcoaches, and School Buses, NHTSA EDR Working Group. DOT HS 809 432, Washington, DC, 2002.

RS-232 was selected as the serial communications standard for these concepts, largely due to its proven durability, simplicity, and low cost. Other communications protocols are available RS-485, RS-422, USB, etc. but these are typically less common, and/or new to the automotive environment. Universal Serial Bus (USB), has become the standard in personal computer serial communications with many accessories and hardware now using it exclusively. It would have been an expectable alternative to RS-232 for these concepts, but the limited data transmission size and rate requirements for these concepts does not necessitate the performance of USB over RS-232. It is recognized; however, that should one of these concepts be implemented in the future, USB may be substituted for the RS-232 connection. This would likely not result in a significant cost difference.

Inertia brakes use electromechanical forces and a clutch pack to convert electrical current into a large amount of torque in the transmission. The inertia brake assists in reducing engine speeds quickly. It usually is connected to the power take off (PTO) opening on the transmission.

National Transportation Safety Board, Safety Recommendation H-99-45 through -54, Washington, DC, November 2, 1999.

American Trucking Associations Technology and Maintenance Council, Guidelines for Event Recording - Collection, Storage, and Retrieval RP 1214, ATA/TMC, 2001.

National Highway Traffic Safety Administration, Notice of Proposed Rulemaking - Event Data Recorders, NHTSA-2004-18029, Washington, DC, June 14, 2004.

It should be noted, that to estimate the memory requirements for each data element estimates where necessary for the field size, frequency, and recording duration for each. Raw field size for time series data elements with high accuracy data (i.e., acceleration) was estimated at 8 bytes, low accuracy data (i.e., accelerator pedal position) was estimated at 4 bytes, digital data (i.e., on/off signals) was estimated at 1 byte, and histogram data was estimated at 40 bytes per histogram. For high frequency data elements (i.e., acceleration) a frequency of 1,000 Hz was used as an estimate, and for low frequency data elements, a frequency of 10 Hz was used as an estimate. For high frequency data, a recording duration of 5 seconds was estimated, for low frequency data, a recording duration of 20 seconds was estimated. These estimates were intended for use in estimating the total raw record size for each data element, which, in turn, was used to estimate the total memory requirements for each concept. These were only intended for estimation purposes and it is entirely probable that the actual field size, frequency, and recording duration would be different if these concepts were manufactured - during the development and testing of the concepts more appropriate values for these would likely be refined and tested.

It should be noted that, for several channels, analog sensor inputs were selected based upon an assessment of the state-of-the-practice. New developments in digital sensors and digital pulse width modulation signaling are enabling many vehicle and electronic manufacturers to move away from analog sensors. As these systems become increasingly more prevalent in the commercial vehicle market, it is likely that many of the sensors in these concepts will utilize digital or digital pulse width modulation input instead of analog sensors.

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