Apparatus and method for detecting obstacles

1. A method for detecting an obstacle in a spatial area, the method comprising:

scanning the spatial area in elevation with a single axis laser range finder at a first frequency while sweeping the single axis laser range finder in azimuth at a second frequency, wherein the first frequency is greater than the second frequency;

classifying each reflection point in the spatial area as one of an obstacle reflection point and a non-obstacle reflection point on a scan line by scan line basis, wherein classifying each reflection point includes:

converting the reflection points to Cartesian coordinates in a scanner-centric frame on a scan line by scan line basis; and

determining a gradient along a dimension of at least one of the scan lines;

fusing only the obstacle reflection points; and

generating statistics associated with the obstacle.

2. The method of claim 1 , wherein scanning the spatial area in elevation includes emitting a succession of light pulses and receiving a succession of reflected light pulses.

3. The method of claim 2 , wherein emitting the succession of light pulses includes emitting the succession of light pulses over a predetermined angular range.

4. The method of claim 1 , wherein sweeping the single axis laser range finder in azimuth includes sweeping the single axis laser range finder over a predetermined angular range.

5. The method of claim 1 , wherein classifying each reflection point includes classifying each reflection point based on a gradient threshold.

6. The method of claim 1 , wherein fusing the obstacle reflection points includes transforming the obstacle reflection points to a common coordinate frame at a predetermined rate.

7. The method of claim 6 , wherein fusing the obstacle reflection points includes defining a cluster of obstacle reflection points.

8. The method of claim 7 , wherein defining the cluster of obstacle reflection points includes defining the cluster based on nearest neighbor criterion.

9. The method of claim 7 , wherein defining the cluster of obstacle reflection points includes defining more than one cluster of obstacle reflection points.

10. The method of claim 1 , wherein generating statistics associated with the obstacle includes defining a height of the obstacle.

11. The method of claim 1 , wherein generating statistics associated with the obstacle includes defining a width of the obstacle.

12. The method of claim 1 , wherein generating statistics associated with the obstacle includes defining a distance the obstacle is positioned from a reference point.

13. The method of claim 1 , wherein generating statistics associated with the obstacle includes defining an angle the obstacle is positioned relative to a reference point.

14. The method of claim 1 , wherein generating the statistics associated with the obstacle includes filtering a cluster of obstacle reflection points.

15. The method of claim 14 , wherein filtering the cluster includes filtering the cluster based on a size threshold.

16. A method for detecting an obstacle in a spatial area, the method comprising:

scanning the spatial area in elevation with a single axis laser range finder at a first frequency while sweeping the single axis laser range finder in azimuth at a second frequency, wherein the first frequency is greater than the second frequency;

classifying each reflection point in the spatial area as one of an obstacle reflection point and a non-obstacle reflection point on a scan line by scan line basis;

fusing only the obstacle reflection points, wherein fusing the obstacle reflection points includes transforming the obstacle reflection points to a common coordinate frame at a predetermined rate; and

generating statistics associated with the obstacle.

17. The method of claim 16 , wherein fusing the obstacle reflection points includes defining a cluster of obstacle reflection points.

18. The method of claim 17 , wherein defining the cluster of obstacle reflection points includes defining the cluster based on nearest neighbor criterion.

19. The method of claim 17 , wherein defining the cluster of obstacle reflection points includes defining more than one cluster of obstacle reflection points.