Obstacle recognition system for vehicle

• US 6,380,885 B2
• Filed: 03/13/2001
• Issued: 04/30/2002
• Est. Priority Date: 03/31/2000
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Morikawa, Katsuhiro, Shirai, Noriaki
• Primary Examiner(s): Gregory, Bernarr E.
• Application Number:
  US09/803,929
• Publication Number:
  US 20010026238A1
• Time in Patent Office: 413 Days
• Field of Search: 342/21, 342/27, 342/28, 342/70, 342/71, 342/72, 342/104, 342/105, 342/107-118, 342/52, 342/53, 342/54, 342/195, 340/435, 340/436, 340/901, 340/902, 340/903, 340/27, 340/28
• US Class Current: 342/70
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 2013/9323 Alternative operation using light waves
• CPC Class Codes: G01S 7/487 Extracting wanted echo signals , e.g. pulse detection

Abstract

Height-wise positions of objects are detected on the basis of distances to the objects from a vehicle, angles of the objects in a width-wise direction of the vehicle, and angles of the objects in a height-wise direction of the vehicle. A plurality of objects, which satisfy conditions predetermined depending on physical characteristics of delineators, are determined to be objects composing a delineator group. When the detected height-wise position of an object in the delineator group which is nearest to the vehicle corresponds to a predetermined value or less, the delineator group is determined to be a delineator group on a road surface. A determination is made as to whether each object in the on-road-surface delineator group is a non-delineator in response to conditions of the detected height-wise positions of the objects in the on-road-surface delineator group.

Claims

1. A vehicle radar obstacle recognition method, comprising:

detecting respective locations of objects within a defined object detection area on the basis of respective distances to the objects from the vehicle, respective first angles formed between respective detected locations of the objects in a primary scanning direction within the defined detection area and a reference axis formed in a secondary scanning direction within the defined detection area, and respective second angles formed between respective detected locations of the objects in the secondary scanning direction and a reference axis in the primary scanning direction;

determining a plurality of objects, which satisfy conditions predetermined depending on physical characteristics of delineators, to be objects composing a delineator group;

when the detected location of an object in the delineator group which is nearest to the vehicle is equal to or less than a predetermined value, determining the delineator group to be a delineator group on a road surface; and

determining whether or not each object in the on-road-surface delineator group is a non-delineator in response to conditions of the respective detected locations of the objects in the on-road-surface delineator group.

2. A vehicle obstacle recognition apparatus, comprising:

radar means for applying a transmission wave to a predetermined angular range in a primary scanning direction and a predetermined angular range in a sub scanning direction, and for detecting distances to objects, first angles of the objects formed between each respective object location in the primary scanning direction and a reference axis in the sub scanning direction, and second angles of the objects formed between each respective object location in the sub scanning direction and a reference axis in the primary scanning direction on the basis of reflected waves which result from reflections of the transmission wave; and

recognizing means for recognizing obstacles ahead of the vehicle on the basis of the distances to the objects, the first angles, and the second angles;

wherein the recognizing means comprises;

1) object recognizing means for detecting respective locations of the objects on the basis of the distances to the objects, the first angles of the objects, and the second angles of the objects;

2) delineator-group determining means for determining ones among the objects which satisfy conditions predetermined depending on physical characteristics of delineators, to be objects composing a delineator group;

3) on-road-surface delineator-group determining means for, when the detected location of an object in the delineator group which is nearest to the vehicle is less than or equal to a predetermined value, determining the delineator group to be a delineator group on a road surface; and

4) non-delineator determining means for determining whether or not each object in the on-road-surface delineator group is a non-delineator in response to conditions of the detected locations of the objects in the on-road-surface delineator group.

3. An apparatus as recited in claim 2, wherein the conditions predetermined depending on the physical characteristics of delineators are that intervals between the objects are smaller than a reference value.

4. An apparatus as recited in claim 2, wherein the conditions of the detected locations of the objects comprise conditions of a variation in the detected locations of the objects.

5. An apparatus as recited in claim 4, wherein the non-delineator determining means comprises means for determining whether or not each object in the on-road-surface delineator group is a non-delineator in response to a position of occurrence of a change among an increase, a decrease, and a constancy in a sequence of the detected locations of the objects.

6. An apparatus as recited in claim 5, wherein the object determined to be the non-delineator is at a place immediately rearward of a position of occurrence of a change from an increase to a decrease in the sequence of the detected locations of the objects as viewed along a direction away from the vehicle.

7. An apparatus as recited in claim 6 wherein the position of the object determined to be the non-delineator is greater than or equal to a predetermined distance above a horizontal reference plane.

8. An apparatus as recited in claim 7, wherein the prescribed height depends on a distance from the present vehicle.

9. An apparatus as recited in claim 5, wherein the object determined to be the non-delineator is at a place immediately rearward of a position of occurrence of a change from a decrease to an increase in the sequence of the detected locations of the objects as viewed along a direction away from the vehicle.

10. An apparatus as recited in claim 2, wherein the object recognizing means comprises means for recognizing shapes of the objects, and the delineator-group determining means comprises means for determining ones among the objects to be objects composing a delineator group in response to the recognized shapes of the objects.

11. An apparatus as recited in claim 2, wherein the object recognizing means comprises means for detecting speeds of the objects relative to the vehicle, means for detecting a speed of the vehicle, and means for determining whether the objects are moving or stationary in response to the detected relative speeds of the objects and the detected speed of the vehicle, and wherein the delineator-group determining means comprises means for determining ones among the stationary objects to be objects composing a delineator group.

12. An apparatus as recited in claim 2, wherein the detected locations of the objects are determined based on the respective second angles.