	US 12,291,218 B2
	Method for calibrating a Lidar sensor
Christian Kobetz, Horb (DE)
Assigned to MERCEDES-BENZ GROUP AG, Stuttgart (DE)
Appl. No. 17/916,229
Filed by MERCEDES-BENZ GROUP AG, Stuttgart (DE)
PCT Filed Feb. 19, 2021, PCT No. PCT/EP2021/054202 § 371(c)(1), (2) Date Sep. 30, 2022, PCT Pub. No. WO2021/197709, PCT Pub. Date Oct. 7, 2021.
Claims priority of application No. 10 2020 109 374.8 (DE), filed on Apr. 3, 2020; and application No. 10 2020 007 645.9 (DE), filed on Dec. 14, 2020.
Prior Publication US 2023/0150519 A1, May 18, 2023
Int. Cl. B60W 50/02 (2012.01); B60W 50/06 (2006.01); B60W 60/00 (2020.01); G01S 7/497 (2006.01); G01S 17/931 (2020.01)

CPC B60W 50/0205 (2013.01) [B60W 50/06 (2013.01); B60W 60/0018 (2020.02); G01S 7/497 (2013.01); G01S 17/931 (2020.01); B60W 2050/0215 (2013.01)]

9 Claims

1. A method, the method comprising:

performing a reference measurement by

projecting, by a Lidar sensor of a vehicle, a first plurality of lines onto a road surface by emitting laser radiation in at least one of a predetermined scanning planes of the Lidar sensor,

detecting, by a photodetector, laser radiation reflected back from the road surface from the projection of the first plurality of lines, and

determining, using the laser radiation reflected back from the road, a distance between the vehicle and each of the first plurality of lines;

performing, at point in time subsequent to the reference measurement a verification measurement by

projecting, by the Lidar sensor, a second plurality of lines onto the road surface by emitting laser radiation in the at least one predetermined scanning plane of the Lidar sensor,

detecting, by the photodetector, laser radiation reflected back from the road surface from the projection of the second plurality of lines, and

determining, using the laser radiation reflected back from the road, a distance between the vehicle and each of the second plurality of lines;

comparing the distances determined using the first plurality of lines with the distances determined using the second plurality of lines;

identifying a degradation of the Lidar sensor if the comparison indicates a deviation greater than a predetermined deviation between the distances determined using the first plurality of lines with the distances determined using the second plurality of lines; and

recalibrating the Lidar sensor responsive to the identification of the degradation of the Lidar sensor, wherein the reference measurement and verification measurement are performed while the vehicle is stationary, wherein the reference measurement is performed when the vehicle is parked and the verification measurement is performed when the vehicle is then restarted.