System and process for correcting gyroscope drift for a motor vehicle

A computer for a system of a motor vehicle, the system having a radar unit for generating a radar signal associated with a detected target positioned about the motor vehicle, a tracker coupled to the radar unit and generating a tracker signal associated with a current radar heading and a current doppler for a stationary target based on the radar signal, a temperature sensor for generating a temperature signal associated with an ambient temperature, a wheel speed sensor for generating a wheel speed signal associated with a current velocity of the motor vehicle, and a gyroscope for generating a gyro signal associated with a measured yaw rate at a current time step, the computer comprising:

• at least one processor coupled to the tracker, the wheel speed sensor, and the gyroscope;
• and
• a non-transitory computer readable storage medium including instructions such that the at least one processor is programmed to:
• receive the tracker signal from the tracker, the wheel speed signal from the wheel speed sensor, the temperature signal from the temperature sensor, and the gyro signal from the gyroscope at the current time step;
• determine with a Kalman filter an innovation, based on a difference between the tracker signal, the wheel speed signal, the temperature signal, the gyro signal, and a plurality of associated predicted observations;
• generate an adapted measurement covariance matrix, based on the innovation vector, and further based on a measurement covariance matrix;
• update the Kalman filter based on the tracker signal, the wheel speed signal, the temperature signal, and the gyro signal;
• predict at least one of the predicted radar heading, the predicted doppler, an estimated gyro scale factor of the gyroscope, a wheel speed sensor scale factor of the wheel speed sensor, and a gyro drift of the gyroscope based on the updated Kalman filter;
• and
• determine a corrected yaw rate while the motor vehicle is in motion, with the corrected yaw rate based on at least the current radar heading, the current doppler effect, and the current velocity of the motor vehicle, and the measured yaw rate at the current time step.

A process of operating a system for a motor vehicle, with the system including a radar unit, a tracker coupled to the radar unit, a wheel speed sensor, a temperature sensor, a gyroscope, and a computer coupled to the tracker, the wheel speed sensor, the temperature sensor, and the gyroscope, and the computer including a at least one processor and a non-transitory computer readable storage medium including instructions, the process comprising:

• generating, using the radar unit, a radar signal associated with a detected target positioned about the motor vehicle;
• generating, using the tracker, a tracker signal associated with a current radar heading and a current doppler for a stationary target based on the radar signal;
• generating, using the wheel speed sensor, a wheel speed signal associated with a current velocity of the motor vehicle;
• generating, using the temperature sensor, a temperature signal associated with an ambient temperature;
• generating, using the gyroscope, a gyro signal associated with a measured yaw rate at a current time step;
• receiving, with the at least one processor, the tracker signal from the tracker, the gyro signal from the gyroscope, and the wheel speed signal from the wheel speed sensor at the current time step;
• determining, with the at least one processor using a Kalman filter, an innovation vector, based on a difference between the tracker signal, the wheel speed signal, the temperature signal, the gyro signal, and a plurality of associated predicted observations;
• generating, using the at least one processor, an adapted measurement covariance matrix, based on the innovation vector, and further based on a measurement covariance matrix;
• updating, using the at least one processor, the Kalman filter based on the tracker signal, the wheel speed signal, the temperature signal, and the gyro signal;
• predicting, using the at least one processor, at least one of the predicted radar heading, the predicted doppler, an estimated gyro scale factor of the gyroscope, a wheel speed sensor scale factor of the wheel speed sensor, and a gyro drift of the gyroscope based on the updated Kalman filter;
• and
• determining, with the at least one processor, a corrected yaw rate while the motor vehicle is in motion, with the corrected yaw rate based on at least the current radar heading, the current doppler effect, and the current velocity of the motor vehicle, and the measured yaw rate at the current time step.