US06
From Wikipedia, the free encyclopedia
The US06 is a driving cycle representing high speed and aggressive acceleration conditions. It is used by the US Environmental Protection Agency (EPA) to measure tailpipe emissions and fuel economy of passenger cars on a vehicle dynamometer.[1]
The US06 is part of the "Supplemental Federal Test Procedure" (SFTP), which was developed to test driving conditions beyond those encountered in the standard highway (HWFET) and city (FTP-75) driving cycles.[2] In 2008, the EPA added the US06 and SC03 supplemental tests, as well as a cold FTP-75, to the original city and highway tests for determination of vehicle fuel economy.[3]
History
The UDDS driving schedule (later adapted to the FTP-75) was originally adopted for federal vehicle emissions testing in 1972.[4] However, this driving cycle had a maximum speed of 57 mph, and the acceleration and deceleration rates were artificially reduced to 3.3 mph/sec (1.5 mps2) due to the limited capabilities of the dynamometers in use at the time.[5] By 1990, it was recognized that these limitations meant that a wide swath of in-use vehicle behavior was not adequately captured by the standard dynamometer tests, and the California Air Resources Board began testing to determine the magnitude of the issue.[6]
Over the next few years, the EPA conducted in-use testing in three different cities (Baltimore, Atlanta, and Spokane, Washington) to analyze the frequency of operations outside the FTP envelope. Multiple cycles based on representative sections of on-road driving data were constructed. Of these, a high speed/load transient control cycle, designated as the US06, was chosen as the best cycle to represent behavior not seen on the FTP.[6]
The use of the SFTP (including the US06) for emissions testing was phased in between 2000 and 2004.[7] In 2008, the US06 was added to the tests used to determine vehicle fuel economy as part of the five-cycle test.[3]
Description
The US06 is a high speed/quick acceleration loop that lasts 10 minutes, covers 8 miles (13 km), averages 48 mph (77 km/h) and reaches a top speed of 80 mph (130 km/h). Four stops are included, and brisk acceleration maximizes at a rate of 8.46 mph (13.62 km/h) per second. The engine begins warm and air conditioning is not used. Ambient temperature varies between 68 °F (20 °C) to 86 °F (30 °C).
The cycle represents an 8.01 mile (12.8 km) route with an average speed of 48.4 miles/h (77.9 km/h), maximum speed 80.3 miles/h (129.2 km/h), and a duration of 596 seconds.[8]