Fail-safe speed profiles for cooperative autonomous vehicles

Method for controlling speed of a vehicle based upon control messages received through a communications device within the vehicle, the method comprising:

• iteratively transmitting a control message from an autonomous controller within the vehicle through a communications device within the vehicle to the system providing propulsion to the vehicle, the control message comprising:
• a current speed command representing an instantaneous desired speed for the vehicle;
• and
• a plurality of future speed commands representing a controlled slowing of the vehicle, said plurality of future speed commands being based upon factors describing preferred operation of the vehicle to a stopped condition;
• monitoring reception of the control message by the system providing propulsion to the vehicle;
• when the monitored reception indicates normal communication, controlling the speed of the vehicle based solely upon the current speed command;
• and
• when the monitored reception indicates anomalous communication, controlling the speed of the vehicle using a speed profile, comprising
• determining a speed profile period containing a distance confirmed to be clear to traverse the vehicle at the time the monitored reception indicates anomalous communication, and
• controlling the speed of the vehicle according to the current speed command at the time the monitored reception indicates anomalous communication until the vehicle has traversed a predetermined percentage of the speed profile period, and subsequently, reducing the speed of the vehicle based upon the plurality of future speed commands;
• wherein the anomalous communication is determined by one of
• irregular control message arrival times from the autonomous controller to the system providing propulsion to the vehicle, and
• mismatched counter measurements between consecutive control messages sent by the autonomous controller to the system providing propulsion to the vehicle.

Method for operating a vehicle within a platoon of vehicles utilizing vehicle-to-vehicle communication, the method comprising:

• monitoring a travel trajectory from a leader vehicle of the platoon of vehicles comprising a relative position of the vehicle with respect to other vehicles within the platoon of vehicles;
• within the vehicle, determining a control message comprising a current speed command and a plurality of future speed commands based upon the monitored travel trajectory;
• transmitting the control message from an autonomous controller within the vehicle for receipt by a system providing propulsion to the vehicle;
• monitoring reception of the control message by the system providing propulsion to the vehicle;
• and
• when the monitored reception indicates anomalous communication, controlling the speed of the vehicle using a speed profile, comprising
• determining a speed profile period containing a distance confirmed to be clear to traverse the vehicle at the time the monitored reception indicates anomalous communication, and
• controlling the speed of the vehicle according to the current speed command at the time the monitored reception indicates anomalous communication until the vehicle has traversed a predetermined percentage of the speed profile period, and subsequently, reducing the speed of the vehicle based upon the plurality of future speed commands;
• wherein the anomalous communication is determined by one of
• irregular control message arrival times from the autonomous controller to the system providing propulsion to the vehicle, and
• mismatched counter measurements between consecutive control messages sent by the autonomous controller to the system providing propulsion to the vehicle.