Obstacle detecting system for vehicles

• US 5,689,264 A
• Filed: 10/05/1995
• Issued: 11/18/1997
• Est. Priority Date: 10/05/1994
• Status: Expired due to Fees

• Current Assignee: Mazda Motor Corporation
• Original Assignee: Mazda Motor Corporation
• Inventors: Okuda, Kenichi, Yoshioka, Tooru, Yamamoto, Yasunori, Ishikawa, Toshihiro, Adachi, Tomohiko, Doi, Ayumu
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US08/539,181
• Time in Patent Office: 775 Days
• Field of Search: 342/70, 342/71, 342/72
• US Class Current: 342/70
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 2013/93185 Controlling the brakes
• CPC Class Codes: G01S 7/411 Identification of targets based on measurements of radar reflectivity G01S7/415 takes precedence
• CPC Class Codes: G01S 7/51 Display arrangements

Abstract

An obstacle detection system for vehicles detects kinetic attributes relative to a vehicle equipped with the system of an object present in a forward path of travel of the vehicle, sets a presumed zone into which the object is expected to have entered at a lapse of a specified period based on the kinetic attributes, and proves an object detected at a lapse of the specified period as the object previously detected if the object of second detection is determined as one having moved into the presumed zone and an obstacle precarious to the vehicle.

Claims

1. An obstacle detection system for a vehicle for detecting an obstacle in the forward path of travel of the vehicle, said obstacle detection system comprising:

object detecting means equipped in a vehicle for detecting kinetic attributes relative to the vehicle of an object present in a forward path of travel of said vehicle at predetermined regular intervals;

object zone setting means for setting a presumed object zone into which said object at a preceding detection is presumed to enter at a latest detection of said object based on said kinetic attributes provided during said preceding detection of said object; and

object proving means for proving an object of said latest detection as said object of said preceding detection when said object of said latest detection is determined to be one that has moved into said presumed object zone based on comparison of kinetic attributes provided during said latest detection of said object with said presumed object zone.

2. An obstacle detection system as defined in claim 1, wherein said kinetic attributes include at least a distance to said object from the vehicle, a directional angle of said object relative to the object and a velocity of said object relative to the vehicle.

3. An obstacle detection system as defined in claim 2, wherein said kinetic attributes further include a size of said object.

4. An obstacle detection system as defined in claim 3, wherein said object detecting means detects an object a number of times during a predetermined detection period of time and determines a size of said object by a method of data averaging.

5. An obstacle detection system as defined in claim 2, further comprising object entry means for selecting objects estimated as obstacles precarious to the vehicle among a plurality of said objects proved by said object proving means and entering only said selected objects as obstacles, and object identifying means for comparing kinetic attributes of each said objects entered with those of another so as to determine identity of each said object with another.

6. An obstacle detection system as defined in claim 5, wherein said object identifying means changes a condition on which identity of each said object with another is determined according to whether said object is moving or stationary.

7. An obstacle detection system as defined in claim 5, wherein said object entry means renews kinetic attributes of said objects entered at regular intervals.

8. An obstacle detection system as defined in claim 2, further comprising object search zone setting means for setting an object search zone surrounding said presumed object zone, wherein said object proving means proves an object of said latest detection as said object of said preceding detection when said object of said latest detection is determined to be one that has moved into one of said presumed object zone and said object search zone based on comparison of kinetic attributes provided during said latest detection of said object with said presumed object zone and said object search zone.

9. An obstacle detection system as defined in claim 2, wherein said object detecting means detects an object a number of times during a predetermined detection period of time and defining an object by one of said kinetic attributes obtained by said number of times of detection most suitable for obstacle determination.

23. An obstacle detection system as defined in claim 1, further comprising object search zone setting means for setting an object search zone surrounding said presumed object zone, wherein said object proving means proves an object of said second detection as said object of said preceding detection when said object of said latest detection is determined to be one that has moved into one of said presumed object zone and said object search zone based on comparison of kinetic attributes provided during said latest detection of said object with said presumed object zone and said object search zone.

24. An obstacle detection system as defined in claim 1, wherein said object detecting means changes an extent of detection according to distances of objects forward from the vehicle.

25. An obstacle detection system as defined in claim 1, wherein, when an object is present in said presumed object zone, said object proving means unconditionally proves that said object has moved into said presumed object zone.

26. An obstacle detection system as defined in claim 1, wherein, when an object is present out of said presumed object zone and said object search zone, said object proving means proves that said object is a new object.

10. An obstacle detection system for a vehicle for detecting an obstacle in the forward path of travel of the vehicle, said obstacle detection system comprising:

object detecting means equipped in a vehicle for detecting kinetic attributes relative to the vehicle of an object present in a forward path of travel of said vehicle;

object zone setting means for setting a presumed object zone into which said object is presumed to have entered at a lapse of a predetermined period of time based on said kinetic attributes provided during a first detection of said object;

object proving means for proving an object second detected at a lapse of said predetermined period of time by said object detecting means as said object of said first detection when said object of said second detection is determined to be one that has moved into said presumed object zone based on comparison of kinetic attributes provided during said second detection of said object with said presumed object zone; and

object entry means for selecting objects estimated as obstacles precarious to the vehicle among a plurality of said objects proved by said object proving means and entering only said selected objects as obstacles, and object identifying means for comparing kinetic attributes of each said objects entered with those of another so as to determine identity of each of said objects with another.

11. An obstacle detection system as defined in claim 10, further comprising object search zone setting means for setting an object search zone surrounding said presumed object zone, wherein said object proving means proves an object of said second detection as said object of said first detection when said object of said second detection is determined to be one that has moved into one of said presumed object zone and said object search zone based on comparison of kinetic attributes provided during said second detection of said object with said presumed object zone and said object search zone.

12. An obstacle detection system as defined in claim 10, wherein said object entry means restricts objects to be entered to less than a predetermined number.

13. An obstacle detection system as defined in claim 10, wherein said object entry means cancels entry of said objects in order of unnecessary degree for obstacle determination so as to enter said object up to said predetermined number.

14. An obstacle detection system as defined in claim 13, wherein said object entry means deletes an object having been entered when said object detecting means does not detect said object continually a predetermined number of times.

15. An obstacle detection system as defined in claim 10, wherein said object entry means changes standards for selecting objects as obstacles precarious to the vehicle between lengthwise distances from the vehicle within and beyond a predetermined distance.

16. An obstacle detection system as defined in claim 15, wherein said object entry means changes said predetermined distance longer with an increase in a velocity of the vehicle.

17. An obstacle detection system as defined in claim 10, wherein said object entry means selects, as obstacles precarious to the vehicle, objects present within a predetermined lateral width stretching from a center line of said forward path of travel for lengthwise distances within said predetermined distance and objects present within a predetermined directional angular with respect to said center line of said forward path of travel for lengthwise distances beyond said predetermined distance.

18. An obstacle detection system as defined in claim 17, wherein said object entry means selects, as obstacles precarious to the vehicle, objects present within a predetermined lateral width stretching from a center line of said forward path of travel for lengthwise distances within said predetermined distance and objects having predetermined relative velocity vectors for lengthwise distances beyond said predetermined distance.

19. An obstacle detection system as defined in claim 18, wherein said object zone setting means changes said presumed object zone in lengthwise distance between lengthwise distances from the vehicle within and beyond said predetermined distance.

20. An obstacle detection system as defined in claim 10, wherein, when an object of said second detection is determined to have moved into and been present in both said presumed object zone and said object search zone, said object proving means proves that said object has moved into one of said presumed object zone and said object search zone in which smaller one of said objects is present.

21. An obstacle detection system as defined in claim 10, wherein said object zone setting means changes said presumed object zone in lateral distance between lengthwise distances from the vehicle within and beyond said predetermined distance.

22. An obstacle detection system as defined in claim 10, wherein said object detecting means includes a radar unit for scanning a field forward from the vehicle.