Project path of travel of blade on a motor grader

A motor grader comprising:

• a front frame supported on a pair of front wheels that are mounted on a front axle;
• a rear frame supported on a pair of rear wheels that are mounted on a rear axle, the rear frame coupled with the front frame;
• a blade movably attached to the front frame, the blade having a blade length that spans between a left outer edge and a right outer edge;
• a vehicle grade control system including:
• one or more sensors arranged to sense a position of one or more actuators operably coupled with the blade, wherein the one or more sensors are also arranged to sense an articulation angle of the rear frame relative to the front frame, wherein the one or more sensors are also arranged to sense a front wheel steering angle of the pair of front wheels;
• a controller including a computing device having a processor and a memory, the controller operatively coupled to the one or more sensors to receive the sensed position of the one or more actuators, the sensed position of the articulation angle, and the sensed position of the front wheel steering angle, the memory storing a grade profile of the ground surface, wherein the controller:
• determines movement of the front frame and the rear frame based on the articulation angle and the front wheel steering angle as the pairs of front and rear wheels travel over a ground surface;
• determines a blade position and a blade movement of the blade with respect to the front and the rear frames based on the sensed position of the one or more actuators and the determined movement of the front frame and the rear frame;
• determines a blade trajectory path for a plurality of points along the blade length, including the left outer edge and the right outer edge, each blade trajectory path representing a predicted path over the ground surface that the corresponding point will travel as the motor grader moves, based on the determined movement of the front frame and the rear frame and the determined blade position and the blade movement of the blade;
• and
• compares, for each of the plurality of points, the corresponding blade trajectory path to the grade profile to determine a deviation between the blade trajectory path and the grade profile.