High precision multi-sensor extrinsic calibration via production line and mobile station

A calibration station for multi-sensor extrinsic calibration in a vehicle, comprising:

• a two-dimensional (2D) calibration target provided around an external environment within a threshold distance of the vehicle;
• and
• a vehicle placement section configured to accommodate the vehicle on the vehicle placement section,
• wherein one or more processors of the vehicle are configured to:
• receive sensor data from a first sensor and a second sensor of the vehicle, the first sensor being a LIDAR sensor and the second sensor being an object-detection sensor or an imaging sensor, the sensor data comprising:
• a three-dimensional (3D) point cloud including a first representation of the 2D calibration target as sensed by the first sensor, the first representation corresponding to a partial representation of the 2D calibration target sensed by the first sensor;
• and
• other image data including a second representation of the 2D calibration target as sensed by the second sensor;
• cluster and segment detection points in the 3D point cloud to detect a shape of the 2D calibration target from the partial representation of the 2D calibration target;
• determine a center of the 2D calibration target using the detected shape of the 2D calibration target;
• determine a center of the 2D calibration target in the second representation based on one or more features of the 2D calibration target in the second representation;
• match the center of the 2D calibration target as determined using the detected shape to the center of the 2D calibration target in the second representation;
• compute a six-degree of freedom rigid body transformation of the first sensor and the second sensor based on the matched centers of the 2D calibration target as determined using the detected shape and of the 2D calibration target in the second representation;
• and
• compute a projection of the first sensor to the second sensor based on the computed six-degree of freedom rigid body transformation of the first sensor and the second sensor.

A calibration system for multi-sensor extrinsic calibration in a vehicle, comprising:

• a two-dimensional (2D) calibration target provided around an external environment within a threshold distance of the vehicle;
• a vehicle placement section configured to accommodate the vehicle for detection of the 2D calibration target;
• and
• one or more processors associated with the vehicle, wherein the one or more processors are configured to:
• receive sensor data from a first sensor and a second sensor of the vehicle, the first sensor being a LIDAR sensor and the second sensor being an object-detection sensor or an imaging sensor, the sensor data comprising:
• a three-dimensional (3D) point cloud including a first representation of the 2D calibration target as sensed by the first sensor, the first representation corresponding to a partial representation of the 2D calibration target sensed by the first sensor;
• and
• other image data including a second representation of the 2D calibration target as sensed by the second sensor;
• cluster and segment detection points in the 3D point cloud to detect a shape of the 2D calibration target from the partial representation of the 2D calibration target;
• determine a center the 2D calibration target using the detected shape of the 2D calibration target;
• determine a center of the 2D calibration target in the second representation based on one or more features of the 2D calibration target in the second representation;
• match the center of the 2D calibration target as determined using the detected shape to the center of the 2D calibration target in the second representation;
• compute a six-degree of freedom rigid body transformation of the first sensor and the second sensor based on the matched centers of the 2D calibration target as determined using the detected shape and of the 2D calibration target in the second representation;
• and
• compute a projection of the first sensor to the second sensor based on the computed six-degree of freedom rigid body transformation of the first sensor and the second sensor,
• wherein the 2D calibration target includes a combination of sensor targets.