Architecture and method for high-integrity branch discrimination

Abstract

A method of determining a traversed branch for a vehicle on a constrained path, the method includes: receiving map-related information; receiving speed information; performing two or more different detection methods from among: inertial detection; magnetometer detection; texture detection; 3D detection; or velocity field detection; and arbitrating among the result of the two or more different detection methods to determine which branch was traversed.

What is claimed is: 
     
         1 . A method of determining a traversed branch for a vehicle on a constrained path, the method comprising:
 receiving map-related information;   receiving velocity information of the vehicle;   performing two or more different detection methods from among:
 inertial detection; 
 magnetometer detection; 
 texture detection; 
 3D detection; or 
 velocity field detection; and 
   arbitrating among the result of the two or more different detection methods to determine which branch was traversed.   
     
     
         2 . The method as claimed in  claim 1 , further comprising:
 receiving incoming switch branch region information.   
     
     
         3 . The method as claimed in  claim 2 , further comprising:
 detecting incoming switch branch region information based on a determined map position of the vehicle.   
     
     
         4 . The method as claimed in  claim 1 , further comprising:
 performing a safety operation in response to the determined branch traversal.   
     
     
         5 . The method as claimed in  claim 4 , wherein the arbitrating comprises:
 comparing a determined branch traversal with an expected or planned branch traversal.   
     
     
         6 . The method as claimed in  claim 1 , wherein the two or more different detection methods generate a branch traversal estimation and a quality value of the branch traversal estimation. 
     
     
         7 . The method as claimed in  claim 6 , wherein the arbitrating includes using the quality value as an input to the determination of which branch was traversed. 
     
     
         8 . The method as claimed in  claim 4 , wherein the safety operation includes at least one of stopping the vehicle, slowing the vehicle, shutting down a section of the path, shutting down a region encompassing both the divergent or main-line paths, stopping the vehicle or shutting down a section of the path until vehicle position is reacquired. 
     
     
         9 . The method as claimed in  claim 1 , further comprising:
 updating a position of the vehicle in response to the determined branch traversal.   
     
     
         10 . The method as claimed in  claim 9 , wherein the updating the position of the vehicle comprises updating a position of the vehicle prior to branch traversal with a position along the determined branch traversal. 
     
     
         11 . A method of detecting a switch branch, comprising:
 receiving branch detection information;   responsive to no additional branch detection information being received within a detection window period, performing arbitration on the received branch detection information and determining which branch was traversed based on the branch detection information;   responsive to additional non-complementary branch detection information being received, determining that no switch branch was detected; and   responsive to additional complementary branch detection information being received, performing arbitration on the received branch detection information and the additional complementary branch detection information and determining which branch was traversed.   
     
     
         12 . The method of  claim 11 , wherein the branch detection information is received from two or more different detection methods from among:
 inertial detection;   magnetometer detection;   texture detection;   3D detection; or   velocity field detection.   
     
     
         13 . The method of  claim 11 , wherein the performing arbitration comprises applying weighting to the received complementary and non-complementary branch detection information. 
     
     
         14 . The method of  claim 11 , wherein the weighting is determined based on one or more of quality of the branch detection information, sensor type, vehicle speed, sensor range, sensor noise, or sensor weather susceptibility. 
     
     
         15 . The method of  claim 11 , further comprising:
 performing a safety operation in response to the determined branch traversal.   
     
     
         16 . The method of  claim 15 , wherein the safety operation includes at least one of stopping the vehicle, slowing the vehicle, shutting down a section of the path, shutting down a region encompassing both the divergent or main-line paths, stopping the vehicle or shutting down a section of the path until vehicle position is reacquired. 
     
     
         17 . The method of  claim 11 , further comprising:
 updating a position of the vehicle in response to the determined branch traversal.   
     
     
         18 . A system for branch traversal discrimination, the system comprising:
 a vehicle configured to travel along a constrained path, the vehicle comprising:
 two or more sensors for detecting a switch branch; and 
 a controller for determining which switch branch was traversed by the vehicle based on data received from the two or more sensors, the controller configured to arbitrate among the sensor data to determine the traversed switch branch. 
   
     
     
         19 . The system of  claim 18 , wherein the controller is further configured to perform a safety operation in response to the determined branch traversal. 
     
     
         20 . The system of  claim 18 , wherein the controller is further configured to update a position of the vehicle in response to the determined branch traversal.