Motion control system determining a longitudinal acceleration command for a vehicle

A method for limiting the speed of a vehicle by a motion control system, the method comprising:

• receiving, by one or more controllers, a current longitudinal vehicle velocity and an autonomous acceleration command;
• determining, by the one or more controllers, a predicted longitudinal velocity of the vehicle based on the current longitudinal vehicle velocity and the autonomous acceleration command;
• determining a predicted lateral acceleration of the vehicle based on the predicted longitudinal velocity of the vehicle;
• determining an allowed longitudinal acceleration of the vehicle based on the predicted lateral acceleration of the vehicle and the current longitudinal vehicle velocity;
• determining a longitudinal acceleration command based on the allowed longitudinal acceleration and the current longitudinal vehicle velocity;
• and
• instructing a prime mover of the vehicle to limit the speed of the vehicle based on the longitudinal acceleration command.

A motion control system for a vehicle including a prime mover, the motion control system comprising:

• one or more controllers in electronic communication with the prime mover, wherein the one or more controllers include one or more processors that execute instructions to:
• receive a current longitudinal vehicle velocity and an autonomous acceleration command;
• determine a predicted longitudinal velocity of the vehicle based on the current longitudinal vehicle velocity and the autonomous acceleration command;
• determine a predicted lateral acceleration of the vehicle based on the predicted longitudinal velocity of the vehicle;
• determine an allowed longitudinal acceleration of the vehicle based on the predicted lateral acceleration of the vehicle and the current longitudinal vehicle velocity;
• determine a longitudinal acceleration command based on the allowed longitudinal acceleration and the current longitudinal vehicle velocity, wherein the longitudinal acceleration command of the vehicle includes an acceleration-based error component that is based on an acceleration-based error term and a velocity-based error component that is based on a velocity-based error term;
• limit the velocity-based error component of the longitudinal acceleration command of the vehicle;
• and
• instruct the prime mover of the vehicle to limit the speed of the vehicle based on the longitudinal acceleration command.