	US 11,893,896 B2
	Systems and methods for determining an angle and a shortest distance between longitudinal axes of a travel way line and a vehicle
Michal Dobes, Olomouc (CZ); Radek Baranek, Litovel (CZ); Milos Sotak, Kosice-Saca (SK); Vijay Venkataraman, Excelsior, MN (US); Vibhor L Bageshwar, Rosemount, MN (US); and Zdenek Kana, Dubnany (CZ)
Assigned to Honeywell Aerospace SAS, Toulouse (FR)
Filed by Honeywell Aerospace SAS, Toulouse (FR)
Filed on Aug. 21, 2020, as Appl. No. 16/999,546.
Prior Publication US 2022/0058969 A1, Feb. 24, 2022
Int. Cl. G08G 5/02 (2006.01); G06V 20/56 (2022.01); G01S 5/06 (2006.01); G08G 5/06 (2006.01)

CPC G08G 5/025 (2013.01) [G01S 5/06 (2013.01); G06V 20/56 (2022.01); G08G 5/065 (2013.01)]

20 Claims

1. A method, comprising:

receiving a captured image;

transforming the captured image to an inverse perspective image;

receiving imager calibration parameter values including intrinsic imager calibration parameters, and extrinsic imager calibration parameters;

determining whether a travel way line candidate is detected in the inverse perspective image;

upon detecting the travel way line candidate in the inverse perspective image, then determining whether the detected travel way line candidate satisfies a first set of travel way line criteria defining a travel way line;

upon determining that the travel way line candidate satisfies the criteria, then determining a longitudinal axis of the detected travel way line candidate;

determining an angle (φ) between a longitudinal axis of a vehicle and the determined longitudinal axis of the detected travel way line candidate, and a shortest distance (d) between a reference point on or in the vehicle or projected onto a surface and the determined longitudinal axis of the detected travel way line candidate; and

determining a value of variances for each of the angle (φ) and the shortest distance (d),

wherein the value of variances are determined using Jacobian transformation matrices, sensor parameters used to obtain the inverse perspective image, measurement error equations, and parameters of the detected travel way line candidate;

wherein the measurement error equations determine estimated measurement errors (err) for the shortest distance (d) and the angle (φ), wherein the measurement error equations are:

err d=(J_d*CovMat*J_d^T)^1/2

err φ=(J_φ*CovMat*J_φ^T)^1/2

where J_dand J_φ are Jacobian matrices for the shortest distance (d) and the angle (φ), respectively, and CovMat is a covariance matrix;

wherein the Jacobian matrices for the shortest distance (d) and the angle (φ) are computed using errors in the intrinsic imager calibration parameters, errors in the extrinsic imager calibration parameters, and errors in the parameters of the detected travel way line candidate;

wherein the value of variances are part of measurement statistics used by a navigation filter in the vehicle to estimate kinematic state statistics of the vehicle.