Class-8 Heavy Truck Duty Cycle Project Final Report - Center for ...

The data analyses performed in Phase 1 indicated that duty cycle data could be generated from the
data that was collected during the Pilot Test. A characteristic data analysis task indicated that for
NGSWBTs, a fuel savings in the range of 2.9 percent to 9.0 percent might be experienced.
Overall, the conduct of the Phase 1 Pilot Test activities allowed the research team to be better prepared
for the conduct of the FOT, in both the analysis of the data generated and in envisioning capabilities for
providing tools for generating custom duty cycle profiles and information. Phase 1 efforts were
concluded in March 2006 (a Phase 1 final report was prepared and submitted to DOE) and Phase 2 was
initiated in April 2006.
Phase 2 was an eighteen-month effort that began in April 2006 and was concluded in September
2007. Phase 2 involved the development of the FOT sensor suite and the instrumentation of six longhaul
heavy trucks. Initial data collection and verification were performed during this phase and were
concluded in Phase 3. A major milestone of Phase 2 efforts was the formal launch of the FOT. This
launch was marked by the signing of a memorandum of understanding (MOU) between Schrader,
UT-Battelle, and DOE on October 23, 2006.
Phase 3 was a seven-month effort which began in October 2007 and concluded in April 2008. Major
Phase 3 efforts involved the completion of the data collection efforts, completion of the DCGenT, and
the conduct of dynamometer testing. The FOT data was archived in a DOE heavy vehicle data
archive system located at ORNL. Data analyses of operational characteristics were also conducted
under Phase 3, and the data archive system was made accessible for use by the research community
and others (with permission from DOE).
1.1 DUTY CYCLE NEEDS OF INDUSTRY/GOVERNMENT
1.1.1 Overview of Duty Cycles
In their simplest form vehicle-based duty cycles have traditionally represented a mapping of a vehicle’s
velocity over time. Duty cycles are also referred to as emission test cycles or drive cycles and are utilized
in conjunction with engine or chassis dynamometers to measure and compare emissions for engines or
vehicles operating with exactly the same duty cycle. In theory, in order to assess the real-world impact of
engines and vehicles, and for the purposes of setting emissions and fuel efficiency standards, duty cycles
should ideally reflect characteristics of real-world vehicle usage patterns. Many existing duty cycles
resemble portions of real-world driving, but were developed for emissions testing and the evaluation of
technologies on a common duty cycle basis. Many real-world duty-cycles are highly dependent on the
specific vocational applications which oftentimes do not resemble existing duty cycles.
A number of emission test cycles used internationally (including the European Union and Japan) and in
the US are presented at: http://www.dieselnet.com/standards/cycles/#us. Such duty cycles have
associated measures such as:
• cycle duration
• average speed
• maximum speed
• maximum acceleration
• maximum deceleration
• distance traveled
• the number of stops per mile
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