Real-time online calibration of coherent doppler lidar systems on vehicles

A method for calibrating an imaging and ranging subsystem, the method comprising:

• receiving, by a processor and from a storage device, sensor data indicative of one or more targets from the imaging and ranging subsystem in the form of point cloud data, location data from a positioning subsystem defining a geographical location of the imaging and ranging subsystem, orientation data from an orientation subsystem defining an orientation of the imaging and ranging subsystem and initial translation and rotation values of the imaging and ranging subsystem;
• generating, by the processor, measured Doppler values based on the sensor data and theoretical Doppler values based on the sensor data, the location data, the orientation data and the initial translation and rotation values;
• comparing, by the processor, the measured Doppler values with the theoretical Doppler values to determine if calibration is necessary,
• wherein if calibration is necessary, calculating, by the processor, correction translation and correction rotation values;
• and
• calculating, by the processor, updated translation and rotation values based on the sensor data, the location data, the orientation data, the initial translation and rotation values, and the correction translation and correction rotation values to calibrate the imaging and ranging subsystem with respect to the vehicle.

A vehicle calibration system, comprising:

• a processor;
• and
• a memory coupled with and readable by the processor and storing therein a set of instructions, which when executed by the processor, cause the processor to provide calibration information by:
• receiving, from the memory, sensor data indicative of one or more targets from the imaging and ranging subsystem in the form of point cloud data, location data from a positioning subsystem defining a geographical location of the imaging and ranging subsystem, orientation data from an orientation subsystem defining an orientation of the imaging and ranging subsystem and initial translation and rotation values of the imaging and ranging subsystem;
• generating measured Doppler values based on the sensor data and theoretical Doppler values based on the sensor data, the location data, the orientation data and the initial translation and rotation values;
• comparing the measured Doppler values with the theoretical Doppler values to determine if calibration is necessary,
• wherein if calibration is necessary, calculating correction translation and correction rotation values;
• and
• calculating updated translation and rotation values based on the sensor data, the location data, the orientation data, the initial translation and rotation values, and the correction translation and correction rotation values to calibrate the imaging and ranging subsystem with respect to the vehicle.