Calibration and operation of vehicle object detection radar with inertial measurement unit (imu)

A dynamic misalignment error correction system for a vehicle-mounted side-directed object-detection radar system comprising:

• an integral, self-contained radar object-detection sensor package adapted for after-market installation on a side of a vehicle or on a side of a trailer adapted to be towed by a vehicle, said radar object-detection sensor package comprising a radar sensor;
• said radar sensor comprising a beam face with x, y and z Cartesian coordinate axes orientation, with said beam face being attached to said radar object-detection sensor package so that the x-axis of the beam face is generally parallel to a straight line approximating the straight, go-ahead or go-back movement direction of the vehicle or trailer, the y-axis of the beam face is generally parallel to a straight line approximating the horizon, and the z-axis of the beam face is generally parallel to a straight line approximating the direction of the earth's gravitational field;
• said radar sensor being adapted, when said radar object-detection sensor package is installed on a side of a vehicle or trailer, to maintain a wide antenna pattern with a main lobe directed perpendicularly to the side of the vehicle or trailer so as to maintain radar coverage principally in next-adjacent, generally-parallel road lanes and the next-far-adjacent, generally-parallel road lanes thereof;
• said radar sensor also comprising an incorporated Inertial Measurement Unit (IMU) containing accelerometer, gyroscope, and magnetometer components integrated together with said radar sensor in said self-contained radar sensor package;
• the IMU being adapted to observe by a first component of the IMU an observed first z-axis of the radar sensor face, in order to determine an offset angle β that is the difference between the radar sensor face observed first z-axis and a gravitational field direction that is an observed second z-axis;
• and
• said self-contained radar object-detection sensor package being adapted to enter and save to send for future consideration the offset angle β for correction of any relevant radar sensor measurement.

A dynamic misalignment error correction system for a vehicle-mounted side-directed object-detection radar system comprising:

• an integral, self-contained radar sensor package adapted for after-market installation on a side of a vehicle or on a side of a trailer adapted to be towed by a vehicle, said radar sensor package comprising a radar sensor;
• said radar sensor comprising a beam face with x, y and z Cartesian coordinate axes orientation, with said beam face being attached to said radar object-detection package so that the x-axis of the beam face is generally parallel to a straight line approximating the straight, go-ahead or go-back movement direction of the vehicle or trailer, the y-axis of the beam-face is generally parallel to a straight line approximating the horizon, and the z-axis of the beam face is generally parallel to a straight line approximating the direction of the earths' gravitational field;
• said radar sensor being adapted, when said radar object-detection sensor package is installed on a side of a vehicle or trailer, to maintain a wide antenna pattern with a main lobe directed perpendicularly to the side of the vehicle or trailer, so as to maintain radar coverage principally in next-adjacent, generally-parallel road lanes and next-far-adjacent, generally-parallel road lanes thereof;
• said radar sensor also comprising an incorporated IMU (Inertial Measurement Unit) containing accelerometer, gyroscope, and magnetometer components integrated together with said radar sensor in said self-contained radar sensor package;
• the IMU being adapted to observe, by a first of the components of the IMU, an observed first x-axis of the radar sensor face, during a straight, go-ahead or go-back movement direction of the vehicle or trailer along an observed second x-axis, in order to determine an offset angle α that is the difference between the radar sensor face observed first x-axis and the vehicle movement direction observed second x-axis;
• the straight, go-ahead or go-back movement of the vehicle or trailer being confirmed by a second component of said IMU adapted to detect any movement of the vehicle or trailer along the y-axis;
• said radar sensor further comprising a third component of said IMU adapted to observe an observed first z-axis of the radar sensor face, in order to determine an offset angle β that is the difference between the radar sensor face observed first z-axis and a gravitational field direction that is an observed second z-axis generally corresponding to the downward and upward direction of the trailer in the earth's gravitational field;
• and
• said self-contained radar object-detection sensor package being adapted to enter and save to send for future consideration the first offset angle α and the second offset angle β for correction of any relevant sensor measurement.

A vehicle-mounted side-directed object-detection radar system comprising:

• an integral, self-contained radar object-detection package adapted for after-market installation on a side of a vehicle or on a side of a trailer adapted to be towed by a vehicle, the package comprising a radar sensor;
• the radar sensor having a beam face with x, y and z Cartesian coordinate axes orientation, with the x-axis being generally parallel to a straight line approximating the go-ahead movement direction of the vehicle or trailer, with the y-axis being generally parallel to a straight line approximating the horizon, and with the z-axis being generally parallel to a straight line approximating the direction of the earth's gravitational field;
• the radar sensor being adapted, when the package is installed on a side of a vehicle or trailer, to maintain a wide antenna pattern with a main lobe directed perpendicularly to the side of the vehicle or trailer so as to maintain radar coverage principally in a next-adjacent, generally-parallel road lane and a next-far-adjacent, generally-parallel road lane thereof;
• the radar system also comprising an Inertial Measurement Unit (IMU) containing accelerometer, gyroscope, and magnetometer components integrated together with the radar sensor in the self-contained radar object-detection package;
• the IMU being adapted to observe and measure, by a first of the components of the IMU, a rotation of the radar object-detection package about the x-axis in order to determine a tilt or rotation angle β′(beta prime), the difference between a beam face observed z-axis and the direction of the earth's gravitational field, that is, the tilt or rotation amount;
• and
• the self-contained radar object-detection package being adapted to enter and save the tilt or rotation angle β′ for future consideration for operation of said vehicle or the trailer.

A vehicle-mounted side-directed object-detection radar system comprising:

• an integral, self-contained radar object-detection package adapted for after-market installation on a side of a vehicle or on a side of a trailer adapted to be towed by a vehicle, the radar object-detection package comprising a radar sensor;
• the radar sensor having a beam face with x, y and z Cartesian coordinate axes orientation, with the x-axis being generally parallel to a straight line approximating the go-ahead movement direction of the vehicle or trailer, with the y-axis being generally parallel to a straight line approximating the horizon, and with the z-axis being generally parallel to a straight line approximating the direction of the earth's gravitational field;
• the radar sensor being adapted, when the radar object-detection package is installed on a side of a vehicle or trailer, to maintain a wide antenna pattern with a main lobe directed perpendicularly to the side of the vehicle or trailer so as to maintain radar coverage principally in a next-adjacent, generally-parallel road lane(s) and next-far-adjacent, generally-parallel road lane thereof;
• the radar system also comprising an Inertial Measurement Unit (IMU) containing accelerometer, gyroscope, and magnetometer components integrated together with the radar sensor in the self-contained radar object-detection package;
• wherein one or more of the components of the IMU are adapted to observe and measure a short-time series of changes of the radar object-detection package along at least one of the x-, y-, or z-axes in order to determine a bounce or vibration amount and frequency thereof;
• and
• the radar object-detection package being adapted to enter and save the bounce or vibration amount and frequency thereof for future consideration for operation of the vehicle or the trailer.