DANGER ZONE MONITORING AT A GRADE CROSSING

• US 20150323663A1
• Filed: 05/04/2015
• Published: 11/12/2015
• Est. Priority Date: 05/07/2014
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Lehnertz, Benedikt
• Granted Patent: US 9,950,723 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B61L 23/041 Obstacle detection
• CPC Class Codes: B61L 29/00 Safety means for rail/road crossing traffic
• CPC Class Codes: B61L 29/30 Supervision, e.g. monitoring arrangements
• CPC Class Codes: G01S 13/72 for two-dimensional tracking, e.g. combination of angle and range tracking, track-while-scan radar
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: G01S 7/411 Identification of targets based on measurements of radar reflectivity G01S7/415 takes precedence

Abstract

In a method for identifying a danger zone to be monitored at a grade crossing, the following are performed: at least one radar sensor is situated at the danger zone; object trajectories from sequences over time of object positions of respective objects moving through the danger zone are ascertained by the radar sensor; the position of at least one traffic path is identified with the aid of an accumulation of object trajectories; the positions of barrier straight lines are ascertained with the aid of radar reflections of the closed barriers; and the danger zone is determined by linking information on the identified position of the at least one traffic path with information on the ascertained position of the barrier straight lines.

Claims

1. A device for identifying a danger zone to be monitored at a grade crossing, comprising:

at least one radar sensor for detecting objects moving through the grade crossing; and

an identification unit configured to;

ascertain object trajectories from sequences over time of object positions of respective objects moving through the danger zone and detected by the radar sensor;

identify position of at least one traffic path with the aid of an accumulation of object trajectories;

ascertain positions of barrier straight lines with the aid of radar reflections of closed barriers; and

determine the danger zone to be monitored by linking information on the detected position of the at least one traffic path to information on the ascertained position of the barrier straight lines.

2. The device as recited in claim 1, wherein the identification unit is configured to identify positions of at least two crossing traffic paths with the aid of two respective accumulations of object trajectories.

3. The device as recited in claim 2, wherein the identification unit is configured to identify the position of at least one track path with the aid of an accumulation of object trajectories, and to identify the position of at least one traffic path which crosses the track path with the aid of at least one additional accumulation of object trajectories.

4. The device as recited in claim 2, wherein the identification unit is configured to geometrically trim, based on the ascertained position of the barrier straight lines, the at least one traffic path whose position has been identified, to a zone within an area limited on opposite sides by the barrier straight lines.

5. The device as recited in claim 2, wherein the identification unit is configured to:

(i) determine object extensions with the aid of object reflections appertaining to respectively identified objects;

(ii) identify a position and a type of at least one traffic path with the aid of an accumulation of object trajectories and with the aid of the object extensions of the respective objects assigned to the object trajectories, wherein the type of at least one traffic path is selected from types including a track path, a roadway lane, and a footpath.

6. The device as recited in claim 2, wherein the identification unit is configured to classify objects which are moving in the danger zone and recorded by the radar sensor with the aid of object reflections appertaining to the respective objects, into object classes of at least one of objects of different sizes and types, wherein trains are assigned to a first object class and one of (i) passenger cars or (ii) persons are assigned to a second object class.

7. The device as recited in claim 6, wherein the identification unit is configured to identify the position of at least one traffic path with the aid of an accumulation of object trajectories related to a selected object class.

8. The device as recited in claim 6, wherein the at least one radar sensor includes a wide-angle radar sensor having a stationary antenna system whose field of view includes an azimuth angle range of at least 90°

.

9. The device as recited in claim 6, wherein the at least one radar sensor includes an FMCW radar sensor which is configured to determine an object position and an object speed of a recorded object.

10. The device as recited in claim 2, wherein the identification unit is configured to verify the ascertained position of barrier straight lines by detection of time intervals in which radar reflections of the closed barriers are recorded, interrupted by time intervals in which radar reflections of the closed barriers are omitted.

11. A method for identifying a danger zone to be monitored at a grade crossing by using location data obtained by at least one radar sensor, in whose field of view the danger zone lies, comprising:

ascertaining object trajectories from sequences over time of object positions of respective objects detected by the radar sensor and moving through the danger zone;

identifying the position of at least one traffic path with the aid of an accumulation of object trajectories;

ascertaining the positions of barrier straight lines with the aid of radar reflections of closed barriers; and

determining the danger zone to be monitored by linking information on the detected position of the at least one traffic path to information on the ascertained position of the barrier straight lines.

12. The method as recited in claim 11, further comprising:

verifying the ascertained position of barrier straight lines by detecting time intervals in which radar reflections of the closed barriers are recorded and which are interrupted by time intervals in which radar reflections of the closed barriers are omitted.