Obstacle detection apparatus for vehicles

• US 5,745,050 A
• Filed: 04/26/1995
• Issued: 04/28/1998
• Est. Priority Date: 10/21/1994
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Nakagawa, Tetsuya
• Primary Examiner(s): Hofsass, Jeffrey
• Assistant Examiner(s): MANNAVA, ASHOK K
• Application Number:
  US08/429,189
• Time in Patent Office: 1,098 Days
• Field of Search: 340/901-905, 340/435, 340/436, 340/438, 250/235, 250/236, 250/224, 180/167, 180/168, 180/169, 180/271
• US Class Current: 340/903
• CPC Class Codes: G08G 1/16 Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08

Abstract

An obstacle detecting apparatus including a light projecting assembly for projecting the laser light generated in a laser light emitting element through a light emitting path, a light introducing assembly for introducing the laser light reflected by an obstacle into a light receiving element through a light receiving path, and a driving motor for driving the light emitting assembly and at least a portion of the light introducing assembly. The light path in the light projecting assembly is different from the light introducing path, and a distance to the obstacle is obtained based on a propagating delay time from emitting the laser light by the laser light emitting element until receiving the laser light by the laser light receiving element. Also included is a direction detecting device for detecting a direction in which the laser light is projected, a light emission level detecting device for detecting a strength of the laser light, a stain detecting device for detecting stains on the housing, and a cleansing device for sweeping the surface of the housing.

Claims

1. An obstacle detecting apparatus, comprising:

a light emitting means;

a light projecting means for projecting a light generated in said light emitting means in a predetermined direction via a light emitting path;

a light introducing means for introducing the light reflected by an obstacle via a light receiving path that is different from said light emitting path over an entire length of said light emitting path and said light receiving path within said obstacle detecting apparatus;

a light receiving means for detecting the light introduced by said light introducing means;

a driving means for rotatably supporting said light projecting means and at least a portion of said light introducing means, and for driving said light projecting means and said at least a portion of said light introducing means in a circumferential direction; and

a calculating means for calculating a distance to the obstacle based on a delay time between a time the light is emitted by said light emitting means until a time the light is received by said light receiving means.

2. The obstacle detecting apparatus of claim 1, wherein said light projecting means comprises:

a first light collecting means for collecting the light generated by said light emitting means; and

a first reflecting means for reflecting said collected light in the predetermined direction.

3. The obstacle detecting apparatus of claim 2, further comprising a first holding means for holding said first light collecting means in a predetermined position.

4. The obstacle detecting apparatus of claim 3, wherein said first holding means comprises:

a first holding member for holding said first light collecting means;

a second holding member movably and adjustably connected with said first holding member and a spring biased between said first and second holding members.

5. The obstacle detecting apparatus of claim 1, wherein

said light introducing means comprises:

a reflecting means for reflecting the introduced light in another predetermined direction; and

a collecting means for collecting the light reflected by said reflecting means.

6. The obstacle detecting apparatus of claim 1, wherein

said light introducing means comprises a reflecting member having a concave shape.

7. The obstacle detecting apparatus of claim 5, further comprising a support means on said driving means for supporting said reflecting means.

8. The obstacle detecting apparatus of claim 1, further comprising a partition member formed between said light projecting means and said light introducing means for preventing the light from interfering therebetween.

9. The obstacle detecting apparatus of claim 8, wherein

said partition member is an electrically conductive material.

10. The obstacle detecting apparatus of claim 1, further comprising a prohibiting means for prohibiting said obstacle detecting apparatus from detecting the obstacle in a predetermined range of rotation of said driving means.

11. The obstacle detecting apparatus of claim 1, further comprising a light emitting origin detecting means provided at a predetermined position in rotation of said light projecting assembly for detecting a light projection direction at the predetermined position.

12. The obstacle detecting apparatus of claim 11, further comprising a direction detecting means for detecting a direction in which the laser light is projected based on the output from said light emitting origin detecting means.

13. The obstacle detecting apparatus of claim 11, further comprising a light emission level detecting means for detecting an intensity of the light projected from said light projecting assembly by comparing the output from said light emitting origin detecting means with a reference value.

14. An obstacle detecting apparatus comprising:

a housing;

a first substrate disposed at a light projecting end of said housing;

a laser light emitting element disposed on said first substrate;

a light projecting assembly for projecting outwardly the laser light generated by said laser light emitting element through a predetermined light emitting path;

a light introducing assembly for introducing the laser light reflected by an obstacle into said housing through a light receiving path that is different from said light emitting path over an entire length of said light receiving path and said light emitting path within said housing;

a second substrate disposed so as to face said first substrate at a light receiving end of said housing;

a laser light receiving element disposed on said second substrate for receiving said introduced laser light;

a motor for driving circumferentially said light emitting assembly and at least a portion of said light introducing assembly;

a counter for calculating a distance to the obstacle based on a delay time between a time the laser light is emitted by said laser light emitting element until a time the light is received by said laser light receiving element; and

a supporting member for supporting said first and second substrates and said motor.

15. The obstacle detecting apparatus of claim 14, wherein said housing comprises a material through which the laser light can be transmitted.

16. The obstacle detecting apparatus of claim 14, wherein said supporting member comprises a material through which the laser light can be transmitted.

17. The obstacle detecting apparatus of claim 14, wherein said motor comprises:

a rotating shaft for rotating circumferentially said light projecting assembly and said light introducing assembly; and

a motor housing having a cylindrical magnet, a coil and a stator.

18. The obstacle detecting apparatus of claim 14, wherein said light projecting assembly comprises:

a light projecting lens for collecting the laser light generated by said laser light emitting element; and

a light projecting mirror for reflecting the collected laser light in a predetermined direction.

19. The obstacle detecting apparatus of claim 18, wherein, said motor shaft is cut at a lower end at an angle of 45°

with respect to an axial direction of said shaft, and said light projecting mirror is attached to the lower end.

20. The obstacle detecting apparatus of claim 14, wherein said light introducing assembly comprises a reflecting member for reflecting the introduced laser light.

21. The obstacle detecting apparatus of claim 14, further comprising a partition between said light projecting assembly and said light introducing assembly for preventing the light from interfering therebetween.

22. The obstacle detecting apparatus of claim 21, wherein said partition is supported at a predetermined position by said supporting member.

23. The obstacle detecting apparatus of claim 14, further comprising a prohibiting means for prohibiting said obstacle detecting apparatus from detecting the obstacle in a predetermined range of rotation of said motor.

24. The obstacle detecting apparatus of claim 14, further comprising a light emitting origin detecting means provided at a predetermined position in rotation of said light projecting assembly for detecting a light projection direction at the predetermined position.

25. The obstacle detecting apparatus of claim 14, further comprising:

a reflected light detecting means provided inside said housing for detecting light reflected inwardly by said housing; and

a stain detecting means for detecting stains on said housing by comparing the output from said reflected light detecting means with a reference value.

26. The obstacle detecting apparatus of claim 25, further comprising:

a housing supporting means for rotatably supporting said housing;

a housing driving means for rotating said housing;

a control means for supplying said housing driving means with a driving signal based on the output from said stain detecting means; and

a cleansing means provided on said housing supporting means for sweeping a surface of said housing.

27. An obstacle detecting apparatus, comprising:

a housing;

a partition disposed in said housing;

light emitting means disposed on a first side of said partition inside said housing;

a first mirror disposed on said first side of said partition inside said housing for reflecting a light generated by said light emitting means through a first portion of said housing and toward an obstacle to be detected;

light receiving means disposed on a second side of said partition inside said housing opposite said first side for detecting the light reflected from the obstacle;

a second mirror disposed on said second side of said partition inside said housing for reflecting the light reflected by the obstacle through a second portion of said housing and toward said light receiving means;

driving means for rotatably driving said first and second mirrors; and

calculating means for calculating a distance to the obstacle based on a delay time between a time when the light is emitted by said light emitting means and a time the light is received by said light receiving means.

28. An obstacle detecting apparatus as recited in claim 27, further comprising a shaft for supporting said first and second mirrors, wherein said shaft extends on both sides of said partition, and wherein said first mirror is supported on one end of said shaft on said first side of said partition, and said second mirror is supported on an opposite end of said shaft on said second side of said partition.

29. An obstacle detecting apparatus as recited in claim 28, wherein said shaft is a motor shaft.

30. An obstacle detecting apparatus, comprising:

a housing;

light emitting means disposed in said housing;

a first mirror disposed in said housing for reflecting a light generated by said light emitting means through a first portion of said housing and toward an obstacle to be detected;

light receiving means disposed in said housing for detecting the light reflected from the obstacle;

a second mirror disposed in said housing for reflecting the light reflected by the obstacle through a second portion of said housing and toward said light receiving means, wherein said first and second mirrors are different, and wherein said first and second portions of said housing are also different;

driving means for rotatably driving said first and second mirrors; and

calculating means for calculating a distance to the obstacle based on a delay time between a time when the light is emitted by said light emitting means until a time the light is received by said light receiving means.

31. An obstacle detecting apparatus as recited in claim 30, further comprising a partition disposed between said first and second mirrors for preventing interference between said light emitting means and said light receiving means.

32. An obstacle detecting apparatus as recited in claim 31, wherein said shaft is a motor shaft.