Systems and methods for optically detecting and identifying objects in an environment

• US 6,875,993 B2
• Filed: 04/12/2001
• Issued: 04/05/2005
• Est. Priority Date: 04/12/2001
• Status: Expired due to Term

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Guenter, James K., Tatum, Jimmy A.
• Primary Examiner(s): Allen, Stephone B.
• Application Number:
  US09/834,220
• Publication Number:
  US 20020148982A1
• Time in Patent Office: 1,454 Days
• Field of Search: 250/559.2, 250/559.4, 250/221, 250/222.1, 250/559.21, 250/559.12, 340/555, 340/556, 340/557, 356/4.01, 356/4.03, 356/4.08, 356/614, 356/625, 356/627, 356/634, 356/635
• US Class Current: 250/559.2
• CPC Class Codes: G01S 7/412 based on a comparison between measured values and known or stored values
• CPC Class Codes: G01S 7/417 involving the use of neural networks
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G01S 7/4815 using multiple transmitters

Abstract

Laser optical sensing systems and methods for detecting object characteristics are disclosed. The system includes a laser source with at least two emission apertures from which laser signals are emitted. The system also includes at least one detector, which is operationally responsive to the laser source. The system can also include a microprocessor that is operationally coupled to the detector(s) for processing signal data, a memory accessible by the microprocessor for storing object characteristics (e.g., unique signals), and a software module accessible by the microprocessor for enabling system training and detection operations. The laser source emits into an environment at least two laser signals, one from each emission aperture. The detector detects the laser signals after the signals pass through the environment, which is occupied by an object, and the microprocessor determines object characteristics based on the matching of laser signals received by the detector(s) and characteristics stored in memory.

Claims

1. An object detection and identification system, comprising:

a laser source with at least two emission apertures, wherein said laser source emits at least two laser signals into an environment;

at least one detector operationally responsive to at least one reflected laser signal, said at least one reflected laser signal receivable by said at least one detector after emission of said at least two laser signals from said laser source into and passing through said environment; and

a microprocessor operationally coupled to said at least one detector and having access to memory containing data associated with said environment and object characteristic data, wherein said microprocessor analyzes said at least one reflected laser signal received by said at least one detector to determine the x, y, and z presence and at least one characteristic of objects entering said environment, said at least one characteristic including at least one of an object'"'"'s size, shape, orientation, speed and reflectance.

2. The system of claim 1, wherein said laser source is a monolithic vertical cavity surface emitting laser array.

3. The system of claim 1, wherein said detector is a photodiode.

4. The system of claim 1 further comprising a memory for providing said system with storage of and access to environment and known object characteristic data.

5. The system of claim 4 including a database wherein characteristics of objects entering said environment are determined by said system based on comparison of said at least one reflected laser signal received by said at least one detector with said known object characteristic data stored in a database.

6. The system of claim 5, wherein said laser source is a vertical cavity surface emitting laser.

7. The system of claim 5, wherein said detector is a photodiode.

8. The system of claim 1 further comprising a database storing reference characteristics of known objects and for providing access to said reference characteristics of known objects to said microprocessor.

9. The system of claim 8 wherein said laser source emits said at least two laser signals into said environment occupied by at least one object, said at least one detector detects said at least one reflected laser signal after said at least two laser signals pass through said environment and said microprocessor determines object characteristics based on comparison of said signals received by said detector with said known object characteristic data stored in said database.

10. The system of claim 9, wherein said laser source is a vertical cavity surface emitting laser.

11. The system of claim 9, wherein said detector is a photodiode.

12. A method for detecting the presence and characteristics of an object entering into and occupying part of a controlled environment using an object detection system, said method comprising the steps of:

sequentially emitting at least two laser signals into said controlled environment using a vertical cavity surface emitting laser structure;

receiving laser signals reflected from at least one object that may be within said controlled environment using at least one detector; and

determining the x, y and z presence of said at least one object in said controlled environment and further determining at least one characteristic of said at least one object, wherein at least one object is present and identifiable where said laser signals reflected by said at least one object are compared to at least one known object characteristics stored in a memory, said at least one known object characteristic including at least one of an object'"'"'s size, shape, orientation, speed and reflectance.

13. A method for detecting the x, y, z presence of and determining the characteristics of an object in an environment, comprising the steps of:

a) training a laser optic object detection system with the characteristics of an environment by;

emitting a first laser signal into a controlled environment using a vertical cavity surface emitting laser structure;

receiving, by at least one detector, a first reflected laser signal reflected off of environmental characteristics representing said environment;

storing said first reflected laser signal in memory, wherein said first reflected laser signal represents said environmental characteristics;

b) training said laser optic object detection system with the characteristics of at least one test object by;

emitting a second laser signal into said controlled environment using said vertical cavity surface emitting laser structure, wherein said at least one test object reflects a second reflected laser signal;

receiving, by said at least one detector, said second reflected laser signal, said second reflected laser signal representing at least one object characteristic; and

storing said at least one object characteristic in said memory; and

c) detecting the presence of at least one object in said controlled environment by;

emitting a third laser signal into said controlled environment wherein an object interferes with said third laser signal and thereby reflects a third reflected laser signal defining the x, y and z location of said target;

receiving, by at least one detector, said third reflected laser signal; and

determining with a microprocessor the characteristics of said at least one object in said controlled environment by comparing said third reflected laser signal to said at least one object characteristic including at least one of an object'"'"'s size, shape, orientation, speed and reflectance.

14. The method of claim 13, wherein characteristics of said at least one object are determined by analyzing a plurality of third reflected laser signals received by said at least one detector after different sequences of said plurality of third reflected laser signals are emitted by said vertical cavity surface emitting laser structure as a plurality of third laser signals.

15. The method of claim 13, wherein angular or spatial location of said at least one object are determined by comparing over time absence of a specific said object by comparing sequences of said laser signals emitted with the sequences of said laser signals previously received by said detector.

16. The method of claim 13, wherein the presence or absence of a specific object is determined by comparing the sequences of said laser signals emitted with the array of said laser signals received by said detector.