System and method for enabling an autonomous vehicle to track a desired path

A method for use in an autonomous vehicle that enables the vehicle to track a desired vehicle path, the method comprising the steps of:

• providing the desired vehicle path to the vehicle;
• executing a vehicle command that causes the vehicle to attempt to follow the desired vehicle path;
• determining an actual vehicle position;
• determining an error between said actual vehicle position and the desired vehicle path;
• and
• reducing said error between said actual vehicle position and the desired vehicle path including the steps of
• planning a continuous path from said actual vehicle position to the desired vehicle path based on said error so that said continuous path converges to the desired vehicle path at a lookahead distance, wherein said continuous path is a quintic polynomial based on said actual vehicle position, the desired vehicle path, and said lookahead distance, and
• compensating for vehicle response characteristics of the vehicle using feedback compensation to cause the vehicle to follow said continuous path.

A system for use with an autonomous vehicle for enabling the vehicle to track a desired vehicle path, the system comprising:

• means for providing the desired vehicle path to the vehicle;
• means for executing a vehicle command that causes the vehicle to attempt to follow the desired vehicle path;
• means for determining an actual vehicle position;
• means for determining an error between said actual vehicle position and the desired vehicle path;
• and
• means for reducing said error between said actual vehicle position and the desired vehicle path including
• means for planning a continuous path from said actual vehicle position to the desired vehicle path based on said error so that said continuous path converges to the desired vehicle path at a lookahead distance, wherein said continuous path is based on said actual vehicle position, the desired vehicle path, and said lookahead distance, and
• means for varying said lookahead distance based on a vehicle speed.