An FPGA implementation of two-step trajectory planning for automatic parking

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2013
Ertuğrul, Halil
The main distinguishing feature of different automatic parking technologies is the method that determines a proper collision-free path. Hereby, the length of the path, the number of halts and the computation time for finding such path are the most relevant performance criteria. In this thesis, a two-step trajectory planning algorithm for automatic parking is considered. The algorithm finds a path that meets all kinematic constraints of the car from its initial position, to the target position while requiring a small number of vehicle halts. It first calculates a collision-free path from the initial position to the target position by maximizing the distance from any obstacle. Since this path usually does not respect the kinematic constraints of the vehicle, a second algorithmic step computes a path that is suitable for the vehicle. In both steps, a set of 48 optimal trajectories is used for the path computations and distance evaluations. Since the trajectory planning algorithm requires complex geometric calculations, it a microprocessor is not suitable for practicable computation times. Hence, an FPGA is chosen for the realization of the trajectory planning algorithm on hardware, enabling parallel processing of the trajectory computations. This thesis describes the hardware design for implementing the trajectory planning algorithm on FPGA. The performed analysis both via simulations and implementation on hardware shows that a speedup in the trajectory computation is obtained. Different from other hardware realizations that are restricted to either only parallel parking or vertical parking, our implementation can handle general parking situations. In addition, our implementation increases the driver comfort by reducing the number of vehicle halts.

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Citation Formats
H. Ertuğrul, “An FPGA implementation of two-step trajectory planning for automatic parking,” M.S. - Master of Science, Middle East Technical University, 2013.