Ray tracing for hidden obstacle detection

• US 10,078,335 B2
• Filed: 06/28/2016
• Issued: 09/18/2018
• Est. Priority Date: 06/28/2016
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Mei, Xue, Sakai, Katsuhiro, Kamata, Nobuhide
• Primary Examiner(s): Shaawat, Mussa A
• Assistant Examiner(s): Kim, Kyung J
• Application Number:
  US15/195,744
• Publication Number:
  US 20170371346A1
• Time in Patent Office: 812 Days
• Field of Search: None
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0248 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

Ray tracing can be used to detect hidden obstacles in an external environment of a vehicle. An outbound sensor signal can be transmitted into an external environment of the vehicle. The outbound sensor signal can be a LIDAR sensor signal. If a return sensor signal is not received for the outbound sensor signal, it can be determined whether an obstacle is located along a projected path of the outbound sensor signal. Such a determination can be made using one or more maps, such as a terrain map and/or a static obstacle map. Responsive to determining that an obstacle is located along the projected path of the outbound sensor signal, a driving maneuver for the vehicle relative to the obstacle can be determined. The vehicle can be caused to implement the determined driving maneuver.

Claims

1. A method of detecting hidden obstacles using ray tracing for a vehicle, the method comprising:

transmitting an outbound sensor signal into an external environment of the vehicle, whereby, when the outbound sensor signal is reflected off of an obstacle in the external environment of the vehicle, the reflected outbound sensor signal can be received as a return sensor signal;

if a return sensor signal is not received for the outbound sensor signal, determining, using at least a map, whether a hidden obstacle is located along a projected path of the outbound sensor signal;

responsive to determining that a hidden obstacle is located along the projected path of the outbound sensor signal, determining a driving maneuver for the vehicle relative to the hidden obstacle; and

causing the vehicle to implement the determined driving maneuver.

2. The method of claim 1, wherein the map is a terrain map, and wherein it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal if the projected path of the outbound sensor signal intersects with a ground surface defined by the terrain map.

3. The method of claim 1, wherein the map is a static obstacle map, and wherein it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal if the projected path of the outbound sensor signal intersects with a static obstacle included in the static obstacle map.

4. The method of claim 1, wherein the outbound sensor signal is a LIDAR sensor signal.

5. The method of claim 1, further including determining at least one of a size or a position of the hidden obstacle, and wherein determining a driving maneuver for the vehicle relative to the hidden obstacle is based at least partially on the determined at least one of the size or the position of the hidden obstacle.

6. The method of claim 1, wherein determining whether a hidden obstacle is located along a projected path of the outbound sensor signal includes:

analyzing the projected path of the outbound sensor signal relative to the map;

if the projected path of the outbound sensor signal intersects with an obstacle defined by the map within a working range of the outbound sensor signal such that a return sensor signal is expected to have been received, then it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal; and

if the projected path of the outbound sensor signal does not intersect with an obstacle defined by the map within a working range of the outbound sensor signal such that a return sensor signal is not expected to have been received, then it is determined that a hidden obstacle is not located along the projected path of the outbound sensor signal.

7. A system of detecting hidden obstacles using ray tracing for a vehicle, the system comprising:

a sensor system, the sensor system being configured to transmit an outbound sensor signal into an external environment of the vehicle and to receive return signals, whereby, when the outbound sensor signal is reflected off of an obstacle in the external environment of the vehicle, the reflected outbound sensor signal can be received as a return sensor signal;

one or more data stores including a map;

a processor operatively connected to the sensor system and to the one or more data stores, the processor being configured to;

if a return sensor signal is not received for the outbound sensor signal, determine, using at least a map, whether a hidden obstacle is located along a projected path of the outbound sensor signal;

responsive to determining that a hidden obstacle is located along the projected path of the outbound sensor signal, determine a driving maneuver for the vehicle relative to the hidden obstacle; and

cause the vehicle to implement the determined driving maneuver.

8. The system of claim 7, wherein the map is a terrain map, and wherein it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal if the projected path of the outbound sensor signal intersects with a ground surface defined by the terrain map.

9. The system of claim 7, wherein the map is a static obstacle map, and wherein it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal if the projected path of the outbound sensor signal intersects with a static obstacle included in the static obstacle map.

10. The system of claim 7, wherein the sensor system includes one or more LIDAR sensors, and wherein the outbound sensor signal is a LIDAR sensor signal.

11. The system of claim 7, wherein the sensor system includes one or more cameras configured to acquire visual data of the external environment of the vehicle, wherein the processor is further configured to determine at least one of a size or a position of the hidden obstacle using visual data acquired by the one or more cameras, and wherein determining a driving maneuver for the vehicle relative to the hidden obstacle is based at least partially on the determined at least one of the size or the position of the hidden obstacle.

12. The system of claim 7, wherein determining whether a hidden obstacle is located along a projected path of the outbound sensor signal includes:

analyzing the projected path of the outbound sensor signal relative to the map;

if the projected path of the outbound sensor signal intersects with an obstacle defined by the map within a working range of the outbound sensor signal such that a return sensor signal is expected to have been received, then it is determined that a hidden obstacle is located along the projected path of the outbound sensor signal; and

if the projected path of the outbound sensor signal does not intersect with an obstacle defined by the map within a working range of the outbound sensor signal such that a return sensor signal is not expected to have been received, then it is determined that a hidden obstacle is not located along the projected path of the outbound sensor signal.

13. A method of detecting hidden obstacles using ray tracing for a vehicle, the method comprising:

transmitting a group of at least three outbound sensor signals into an external environment of the vehicle, the group of at least three outbound sensor signals including a first end signal, a second end signal, and an intermediate signal, the intermediate signal being located between the first end signal and the second end signal, whereby, when one of the outbound sensor signals is reflected off of an obstacle in the external environment of the vehicle, the reflected outbound sensor signal can be received as a return sensor signal;

receiving return sensor signals from at least a subset of the group of at least three outbound sensor signals;

if a return sensor signal is received for the first end signal and for the second end signal but a return signal is not received for the intermediate signal, determining, using at least a map, whether a hidden obstacle is located along a projected path of the intermediate signal;

responsive to determining that a hidden obstacle is located along the projected path of the intermediate signal, determining a driving maneuver for the vehicle relative to the hidden obstacle; and

causing the vehicle to implement the determined driving maneuver.

14. The method of claim 13, wherein the map is a terrain map, wherein determining whether a hidden obstacle is located along the projected path of the intermediate signal includes comparing the projected path of the intermediate signal to the terrain map, and wherein it is determined that a hidden obstacle is located along the projected path of the intermediate signal if the projected path of the intermediate signal would intersect with a ground surface defined by the terrain map within a working range of the intermediate signal.

15. The method of claim 13, wherein the map is a static obstacle map, wherein determining whether a hidden obstacle is located along a projected path of the intermediate signal includes comparing the projected path of the intermediate signal to the static obstacle map, and wherein it is determined that a hidden obstacle is located along the projected path of the intermediate signal if the projected path of the intermediate signal would intersects with a static obstacle included in the static obstacle map within a working range of the intermediate signal.

16. The method of claim 13, wherein the group of at least three outbound sensor signals are LIDAR sensor signals.

17. The method of claim 13, further including determining at least one of a size or a position of the hidden obstacle, and wherein determining a driving maneuver for the vehicle relative to the hidden obstacle is based at least partially on at least one of the determined size or the determined position of the hidden obstacle.

18. The method of claim 17, wherein determining at least one of the size or the position of the hidden obstacle is based on visual data of the external environment acquired by one or more cameras.

19. The method of claim 13, wherein determining whether a hidden obstacle is located along a projected path of the intermediate signal includes:

analyzing the projected path of the intermediate sensor signal relative to the map;

if the projected path of the intermediate sensor signal intersects with an obstacle defined by the map within a working range of the intermediate sensor signal such that a return sensor signal is expected to have been received, then it is determined that a hidden obstacle is located along the projected path of the intermediate sensor signal; and

if the projected path of the intermediate sensor signal does not intersect with an obstacle defined by the map within a working range of the intermediate sensor signal such that a return sensor signal is not expected to have been received, then it is determined that a hidden obstacle is not located along the projected path of the intermediate sensor signal.

20. A system of detecting hidden obstacles using ray tracing for a vehicle, the system comprising:

a sensor system, the sensor system being configured to transmit a group of at least three outbound sensor signals into an external environment of the vehicle and to receive return signals, the group of at least three outbound sensor signals including a first end signal, a second end signal, and an intermediate signal, the intermediate signal being located between the first end signal and the second end signal, whereby, when one of the outbound sensor signals is reflected off of an obstacle in the external environment of the vehicle, the reflected outbound sensor signal can be received as a return sensor signal;

a processor operatively connected to the sensor system, the processor being configured to;

if a return sensor signal is received for the first end signal and for the second end signal but a return signal is not received for the intermediate signal, determine, using at least a map, whether a hidden obstacle is located along a projected path of the intermediate signal;

responsive to determining that a hidden obstacle is located along the projected path of the intermediate signal, determine a driving maneuver for the vehicle relative to the hidden obstacle; and

cause the vehicle to implement the determined driving maneuver.

21. The system of claim 20, further including one or more data stores operatively connected to the processor, wherein the map is a terrain map, wherein the one or more data stores include the terrain map, wherein determining whether a hidden obstacle is located along the projected path of the intermediate signal includes comparing the projected path of the intermediate signal to the terrain map, and wherein it is determined that a hidden obstacle is located along the projected path of the intermediate signal if the projected path of the intermediate signal would intersect with a ground surface defined by the terrain map within a working range of the intermediate signal.

22. The system of claim 20, further including one or more data stores operatively connected to the processor, wherein the map is a static obstacle map, wherein the one or more data stores include the static obstacle map, wherein determining whether a hidden obstacle is located along a projected path of the intermediate signal includes comparing the projected path of the intermediate signal to the static obstacle map, and wherein it is determined that a hidden obstacle is located along the projected path of the intermediate signal if the projected path of the intermediate signal intersects with a static obstacle included in the static obstacle map within a working range of the intermediate signal.

23. The system of claim 20, wherein the sensor system includes one or more LIDAR sensors, and wherein the group of at least three outbound sensor signals are LIDAR sensor signals.

24. The system of claim 20, wherein the processor is further configured to determine at least one of a size or a position of the hidden obstacle, and wherein determining a driving maneuver for the vehicle relative to the hidden obstacle is based at least partially on at least one of the determined size or the determined position of the hidden obstacle.

25. The system of claim 24, wherein the sensor system includes one or more cameras configured to acquire visual data of the external environment of the vehicle, wherein determining at least one of the size or the position of the hidden obstacle is based on visual data of the external environment acquired by one or more cameras.

26. The system of claim 20, wherein determining whether a hidden obstacle is located along a projected path of the intermediate signal includes:

analyzing the projected path of the intermediate sensor signal relative to the map;

if the projected path of the intermediate sensor signal intersects with an obstacle defined by the map within a working range of the intermediate sensor signal such that a return sensor signal is expected to have been received, then it is determined that a hidden obstacle is located along the projected path of the intermediate sensor signal; and

if the projected path of the intermediate sensor signal does not intersect with an obstacle defined by the map within a working range of the intermediate sensor signal such that a return sensor signal is not expected to have been received, then it is determined that a hidden obstacle is not located along the projected path of the intermediate sensor signal.