Electronic power steering system rack force observer vehicle diagnostics

An electronic power steering system comprising:

• a steering rack;
• at least one wheel;
• a brake system module;
• a wheel speed sensor module;
• an inertial measurement unit module;
• a position control module;
• a motion control module;
• a GPS module;
• an electronic steering system rack force observer;
• a rack force observer vehicle diagnostic module;
• at least one computing device;
• memory that stores computer-executable components;
• a processor that executes the computer-executable components stored in the memory, wherein the computer-executable components when executed by the processor cause the acts of:
• receiving and analyzing rack force data from the electronic steering system rack force observer;
• vehicle speed data from the wheel speed sensor module;
• vehicle state data from the inertial measurement unit module;
• vehicle network data from the brake system module;
• and positional data from the GPS module;
• using the electronic steering system rack force observer to perform the acts of monitoring electric current inside the electronic steering system relative to an electric motor position, calculating rack force data on a steering rack using the monitored electric current inside the electronic steering system relative to an electric motor position, determining when the calculated rack force is unexpected;
• calculating steering offset diagnostic data by measuring at least one of a steering angle or a steering velocity of the vehicle relative to a straight position, vehicle speed data from the wheel speed sensor module, vehicle state data from the inertial measurement unit module, vehicle network data from the brake system module, or position data from the GPS module;
• communicating the steering offset diagnostic data to the motion control module;
• calculating a compensated target steering angle based on rack force data relative to the straight position of the steering angle to account for sudden changes in rack forces;
• communicating the calculated compensated target steering angle to the position control module;
• and
• adjusting the steering angle of the at least one wheel based on the calculated compensated target steering angle when the calculated rack force data is unexpected based upon the measured steering angle.

An electronic power steering system comprising:

• a steering rack;
• at least one wheel;
• a brake system module;
• a wheel speed sensor module;
• an inertial measurement unit module;
• a position control module;
• a motion control module;
• a GPS module;
• an electronic steering system rack force observer;
• a rack force observer vehicle diagnostic module;
• at least one computing device;
• memory that stores computer-executable components;
• a processor that executes the computer-executable components stored in the memory, wherein the computer-executable components when executed by the processor cause the acts of:
• receiving and analyzing rack force data from the electronic steering system rack force observer;
• vehicle speed data from the wheel speed sensor module;
• vehicle state data from the inertial measurement unit module;
• vehicle network data from the brake system module;
• and positional data from the GPS module;
• using the electronic steering system rack force observer to perform the acts of monitoring electric current inside the electronic steering system relative to an electric motor position, calculating rack force data on a steering rack using the monitored electric current inside the electronic steering system relative to an electric motor position, determining when the calculated rack force is unexpected;
• calculating steering offset diagnostic data by measuring at least one of a steering angle or a steering velocity of the vehicle relative to at least one of a straight position, vehicle speed data from the wheel speed sensor module, vehicle state data from the inertial measurement unit module, vehicle network data from the brake system module, or position data from the GPS module;
• communicating the steering offset diagnostic data to the motion control module;
• receiving the steering offset diagnostic data from the rack force observer vehicle diagnostic module;
• calculating a compensated target steering angle based on rack force data relative to the straight position of the steering angle to account for sudden changes in rack forces;
• communicating the calculated compensated target steering angle to the position control module;
• and
• adjusting the steering angle of the at least one wheel based on the calculated compensated target steering angle when the rack force data is unexpected based upon the measured steering angle.