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Driving the Traction Circle
Technical Paper
2004-01-3545
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
It is time to introduce a new component to motorsports engineering - the driver. SAE papers rarely deal with the cognitive control system which fills the space between the steering wheel and the seat. It seems that only the safety papers admit the presence of a driver, and they treat the driver as a passive object to be protected.
It is the driver who controls the race car. It is the driver who utilizes, or misuses, the capabilities of the car. It is the driver who chooses a path for the vehicle. It is the driver who decides how to use the traction circle to negotiate a turn in hopes of optimizing lap time.
The traction circle is a G-G diagram of longitudinal acceleration as a function of lateral acceleration. It defines the capability of a vehicle to combine acceleration with cornering while exiting a turn or deceleration with cornering while entering a turn.
Combining acceleration with cornering is universal because it offers greater control than driving a constant arc at maximum lateral acceleration. Combining deceleration or braking with cornering, often called trail braking, is much more difficult and controversial.
The traction circle describes vehicle acceleration and thus determines the path a vehicle follows. This path is usually called a racing line.
This paper will explore the subject of trail braking and test the concept on a simple oval. It will include a literature review of driving books. A mathematical simulation will suggest several lines. These lines will be evaluated on a test oval at the Transportation Research Center in Ohio.
The results will show the effect of different lines and demonstrate effective ways to analyze driver data. The traction circle is a useful analytical concept but it can be deceptive if misused. The traction circle can be augmented with additional information.
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Authors
Topic
Citation
Mitchell, W., Schroer, R., and Grisez, D., "Driving the Traction Circle," SAE Technical Paper 2004-01-3545, 2004, https://doi.org/10.4271/2004-01-3545.Also In
References
- Milliken, William F. Milliken, Douglas L. “Race Car Vehicle Dynamics” SAE 1995
- Wright, Peter “Formula 1 Technology” SAE 2001
- Wright, Peter “Ferrari Formula 1” SAE International 2003
- Donohue, Mark Van Valkenburgh, Paul “The Unfair Advantage” Dodd, Mead and Company 1975
- Jenkinson, Denis “The Racing Driver” B.T. Batsford, Ltd. 1958
- Taruffi, Piero “The Technique of Motor Racing” Robert Bentley, Inc 1959
- Frere, Paul “Sports Car and Competition Driving” Robert Bentley, Inc. 1963
- Moss, Pat Carlsson, Erik “The Art and Technique of Driving” William Heinemann, Ltd. 1965
- Honegger, Walter “The Theory and Practice of High Speed Driving” Hallwag 1969
- Johnson, Alan “Driving in Competition” Bond-Parkhurst Publications 1971
- Van Valkenburrg, Paul “Chevrolet=Racing?” Walter R. Haessner and Associates, Inc. 1972
- Lauda, Niki “Formula 1” Verlag orec Vienna 1975
- Lauda, Niki “The Art and Science of Grand Prix Driving” Motorbooks International Publishers & Wholesalers, Inc. 1977
- Holbert, Al Holbert, Bob Bochrach, Al “Driving to Win” AZTEC Corporation 1982
- Bondurant, Bob “Bob Bondurant on High Performance Driving” Motorbooks International 1982
- Watts, Henry A. “Secrets of Solo Racing” Loki Publishing 1989
- Anderson, George A “Winning: A Race Driver's Handbook” Motorbooks International, Inc 1993
- Smith, Carroll “Drive to Win” Carroll Smith Consulting 1996
- Lopez, Carl “Going Faster” Robert Bentley, Inc. 1997
- Hall, Jim II Smith, Steve “Kart Driving Techniques” Steve Smith Autosports 1999
- Bentley, Ross “Speed Secrets” MBI Publishing Company 1999
- Bondurant, Bob Bentley, Ross “Bob Bondurant on Race Kart Driving” Motorbooks International 2002
- Bentley, Ross “Speed Secrets 2” Motorbooks International 2003
- Parsons, Benny Smith, Steve “Stock Car Driving techniques” Steve Smith Autosports 1973
- Wm. C. Mitchell Software The Driving Simulator Mooresville, NC, USA
- Mitchell, Wm. C, “Analyzing Lines” Racecar Engineering 14 3
- Zapletal, Erik “Trail Blaking” Racecar Engineering 14 8
- How, Jonathon Pohlman, Nicholas Park, Chan-Woo “GPS Estimation Algorithms for Precise Velocity, Slap and Race-Track Position Measurements” SAE 2002-01-3336
- Fey, Buddy “Data Power” Towery Publishing, Inc. 1993
- Wm. C. Mitchell Software Debrief3 Mooresville, NC USA
- Mitchell, Wm. C. Unger, Mike Schroer, Roger Grisez, Dennis B. “Training Test Drivers with Data Acquisition” SAE 2000-01-3568 SAE
- Mitchell, Wm. C. “A Method for Data Alignment” SAE 983087 SAE
- Muhlmeier, Martin Muller, Norbert “Optimization of the Driving Line on a Race Track.” SAE 2002-01-3339