Patent ID: 9405293
Filing Date: 2016-08-02
CPC Classification: B60W,B62D,G01C,G05D,G06Q

Claim Text:
1. A method for controlling an autonomous vehicle, comprising: obtaining, by one or more processors, information describing a roadway from a starting position to a goal position; defining, by the one or more processors, a plurality of layers along the roadway at spaced locations between the starting position and the goal position, each layer having a respective first width, and each layer having a plurality of nodes that are spaced from one another transversely with respect to the roadway within the respective first width; determining, by the one or more processors, a trajectory from the starting position to the goal position, by minimizing a cost value associated with traversing the layers, including, for each layer: defining a plurality of refinement layers along the roadway at spaced locations between the starting position and the goal position, each refinement layer having a respective second width that extends transversely outward from the trajectory and is less than or equal to a transverse width between transversely adjacent pairs of the nodes from each layer of the plurality of layers, and each layer having a plurality of refinement nodes that are spaced from one another transversely with respect to the roadway; modifying the trajectory by minimizing a cost value associated with traversing the refinement layers, wherein modifying the trajectory includes, for each refinement layer: outputting a steering control signal based on the trajectory to a steering device for controlling operation of the steering device; and changing a steering angle of at least one steered wheel using the steering device in response to the steering control signal.