Object detecting apparatus

• US 4,558,215 A
• Filed: 02/08/1983
• Issued: 12/10/1985
• Est. Priority Date: 03/30/1982
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Square Enix
• Original Assignee: Agency of Industrial Science & Technology (Government of Japan), Ministry of International Trade & Industry (Government of Malaysia)
• Inventors: Tachi, Susumu, Kaneko, Makoto, Komoriya, Kiyoshi
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Eyssallene, R.
• Application Number:
  US06/464,914
• Time in Patent Office: 1,036 Days
• Field of Search: 250/221, 250/222.1, 250/203 R, 250/236, 250/224, 340/555-557, 356/1, 356/4, 356/376, 350/6.5, 350/6.9
• US Class Current: 250/222.1
• 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

Abstract

Object detecting apparatus for use, for example, upon a mobile robot to detect objects or obstacles such that the robot may navigate clear of such objects or obstacles includes a source of light for projecting a light beam (7) convergingly toward an axis (9) so as to intersect the axis. The light beam (7) is rotated about the axis (9) within a circular locus (10) while the predetermined converging angle of the beam (7) is maintained constant with respect to the axis (9) so as to generate a light beam detecting surface (8). A condensing lens (2) and light detector (3) are coaxially disposed upon the axis (9) along with the circular locus (10) of the light beam (7) so as to define a viewing field or volume (5). An object-to-be-detected (6) may therefore be detected when the same is illuminated by the projected light beam (7) and its envelope surface (8), and the light reflected from the object (6) is transmitted back to the lens (2) and light detector (3). In a first embodiment of the invention, the light source (4) may itself be rotated about the axis (9) within the circular locus (10) or alternatively, in a second embodiment, the light source (4) may be fixed but have its light beam transmitted to an axially disposed mirror (12) and a peripherally disposed mirror (13) which are rotated within the circular locus (10).

Claims

1. Apparatus for detecting the presence of an object within a spatial region disposed downstream of said apparatus, comprising:

an axis extending through said spatial region within which said object to be detected is disposed;

means for projecting a beam of light in said downstream direction into said spatial region so as to intersect said axis at a predetermined angle with respect to said axis;

means for rotating said light beam projecting means in a circle about said axis while maintaining said predetermined angle of said projecting means with respect to said axis so as to define a conical detecting surface, within said spatial region within which said object to be detected is disposed, for illuminating said object to be detected; and

optical means, disposed upon said axis upstream of said spatial region within which said object to be detected is disposed, for receiving light reflected from said illuminated object,

whereby said object to be detected is capable of being detected.

2. Apparatus as set forth in claim 1, wherein:

said means for projecting said beam of light comprises a light source disposed at said predetermined angle with respect to said axis.

3. Apparatus as set forth in claim 1, wherein said means for projecting said beam of light comprises:

a light source fixedly disposed upon said axis;

a first mirror disposed upon the circumference of said circle; and

a second mirror disposed upon said axis for transmitting said light beam from said light source to said first mirror.

4. An object detecting apparatus according to claim 2 wherein the light source is a semiconductor laser.

5. Apparatus as set forth in claim 3, wherein:

said means for rotating said light beam projecting means comprises means for rotating said first and second mirrors about said axis.

6. Apparatus as set forth in claim 2, wherein:

said light source comprises a light emitting diode.

7. Apparatus as set forth in claim 1, wherein:

said optical means comprises a condensing lens and a light detector.

8. Apparatus as set forth in claim 7, wherein:

said light detector comprises a solar battery.

9. Apparatus as set forth in claim 7, wherein:

said condensing lens and said light detector are both disposed downstream of said light beam projecting means.

10. Apparatus as set forth in claim 7, wherein:

said condensing lens is disposed downstream of said circle within which said light beam projecting means is disposed; and

said light detector is disposed upstream of said circle within which said light beam projecting means is disposed.

11. Apparatus as set forth in claim 7, wherein:

said condensing lens and said light detector are both disposed upstream of said circle within which said light beam projecting means is disposed.

12. Apparatus as set forth in claim 7, wherein:

said condensing lens is disposed in a co-planar manner with respect to said circle within which said light beam projecting means is disposed; and

said light detector is disposed upstream of said condensing lens and said circle within which said light beam projecting means is disposed.

13. Apparatus as set forth in claim 1, wherein:

said object detecting apparatus is mounted upon a mobile robot.

14. Apparatus for detecting the presence of an object within a spatial region disposed downstream of said apparatus, comprising:

an axis extending through said spatial region within which said object to be detected is disposed;

means for projecting a beam of light in said downstream direction into said spatial region so as to intersect said axis at a predetermined angle with respect to said axis;

means for rotating said light beam projecting means in a circle about said axis while maintaining said predetermined angle of said projecting means with respect to said axis so as to define a conical detecting surface, within said spatial region within which said object to be detected is disposed, for illuminating said object to be detected; and

optical means, disposed upon said axis upstream of said spatial region within which said object to be detected is disposed, for defining a viewing volume encompassing said conical detecting surface generated by said rotated light beam projecting means within which light reflected from said illuminated object is able to be received,

whereby said object to be detected is capable of being detected.

15. Apparatus as set forth in claim 14, wherein:

said light beam projecting means comprises a light source disposed upon the periphery of said circle.

16. Apparatus as set forth in claim 15, wherein:

said light source comprises a semiconductor laser.

17. Apparatus as set forth in claim 14, wherein said light beam projecting means comprises:

a light source fixedly disposed upon said axis;

a first mirror disposed upon the circumference of said circle; and

a second mirror disposed upon said axis for transmitting said light beam from said light source to said first mirror.

18. Apparatus as set forth in claim 17, wherein;

said means for rotating said light beam projecting means comprises means for rotating said first and second mirrors about said axis.

19. Apparatus as set forth in claim 14, wherein:

said optical means comprises a condensing lens and a light detector disposed upstream of said condensing lens.

20. Apparatus as set forth in claim 14, wherein:

said object detecting apparatus is mounted upon a mobile robot.