Optimal Overtaking in NASCAR

This article studies the impact of aerodynamic drafting on optimal overtaking maneuvers in NASCAR. Two interlinked optimal control problems (OCPs) are employed: one for computing the strategy of the overtaken car and the other for the overtaking vehicle. Intervehicular interaction is due to a combination of aerodynamic drafting and collision avoidance. In the formulation presented, the cross coupling between these OCPs is unidirectional, with collision avoidance the responsibility of the overtaking vehicle. The racing vehicles are assumed to travel on a highly banked 3-D closed-circuit track. The overtaking car is subject to near-field aerodynamic interactions (“drafting”) that have a significant impact on the overtaking vehicle’s strategy. Results are presented that illustrate overtaking strategies with and without drafting; differences in the two strategies highlight the importance of drafting influences. The results are based on a Generation 7 (Gen 7) NASCAR driven on the Darlington Raceway.