Methods and systems for determining and controlling vehicle speed

A non-transitory computer-readable storage medium having computer-executable instructions embodied thereon that, when executed by at least once computer processor cause the computer processor to:

• determine a grade of the roadway at defined intervals along the roadway;
• calculate a maximum straight line vehicle speed for each defined interval based on vehicle performance data and the determined grade;
• determine a radius of curvature and a superelevation of the roadway for each defined interval;
• determine a lateral friction coefficient for a vehicle/roadway system;
• calculate a maximum cornering vehicle speed for each defined interval based on the curvature, superelevation, and lateral friction coefficient;
• calculate a vehicle speed for each defined interval based on the maximum straight line vehicle speed, the maximum cornering vehicle speed;
• and
• present the calculated vehicle speed for each defined interval in a user-discernible form.

A computer implemented method of determining a vehicle travel speed on a roadway, comprising:

• determining a grade of the roadway at defined intervals along the roadway;
• calculating, using a computer, a maximum straight line vehicle speed for each defined interval based on the determined grade and vehicle performance data;
• determining a radius of curvature and a superelevation of the roadway for each defined interval;
• determining a lateral friction coefficient for a vehicle/roadway system;
• calculating, using the computer, a maximum cornering vehicle speed for each defined interval based on the curvature, superelevation, and lateral friction coefficient;
• and
• calculating, using the computer, the travel speed for the vehicle for each defined interval based on the maximum straight line vehicle speed and the maximum cornering vehicle speed.

A system for determining and controlling a travel speed for a vehicle on a roadway, comprising:

• a road grade tool, said road grade tool determining a grade of a roadway at defined intervals along the roadway based on sensor data from the vehicle;
• a straight line speed tool, said straight line speed tool calculating a maximum straight line vehicle speed for each defined interval based on the determined grade from said road grade tool and vehicle performance data;
• a road curvature tool, said road curvature tool calculating a road curvature and superelevation based on sensor data from the vehicle;
• a friction tool, said friction tool determining a lateral friction coefficient between the vehicle and the roadway;
• a cornering speed tool, said cornering speed tool calculating a maximum cornering vehicle speed for each defined interval based on the curvature, superelevation, and lateral friction coefficient;
• a processing system operatively associated with said road grade tool, said straight line speed tool, said road curvature tool, said friction tool, and said cornering speed tool, said processing system calculating a travel speed for each defined interval based on the maximum straight line vehicle speed and the maximum cornering vehicle speed;
• and
• a vehicle speed control system operatively associated with said processing system, said speed control system controlling the speed of the vehicle so that it does not exceed the calculated travel speed for each defined interval.