Laser optical area scanner and response system and methods

• US 20020148944A1
• Filed: 04/12/2001
• Published: 10/17/2002
• Est. Priority Date: 04/12/2001
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Guenter, James K., Tatum, Jimmy A.
• Granted Patent: US 6,787,756 B2
• Time in Patent Office: Days
• US Class Current: 250/203.1
• 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

Multiple laser optical sensing systems and methods for detecting target characteristics are disclosed. The present invention detects the presence of an object in a monitored area using an laser-based object detection system and may selectively cause a controlled response when an object is detected. At least two laser signals may be emitted into a monitored area using a vertical cavity surface emitting laser structure. At least one detector receives any laser signals not blocked by an object. The system determines the presence or absence of an object in the environment using a microprocessor and determines the objects characteristics by comparing received laser signals associated with it to object characteristics stored in a memory. The system may selectively causing a controlled response in accordance with the determination of object characteristics and/or correlating response criteria.

Claims

1. An area scanning system, comprising:

a laser source with at least two signal emission apertures;

at least one detector operationally responsive to signals emitted from said laser source;

a microprocessor operationally coupled to said at least one detector; and

a control module for triggering a response to the presence of at least one a particular object in said environment;

wherein said laser emits at least two laser signals into an environment previously known by said system to be object free, said at least one detector detects said at least two laser signals after said signals pass through said environment, and said microprocessor analyzes said laser signals received by said detector to determine the presence of particular objects, known by said system, within said environment.

4. The system of claim 1, wherein said laser is a vertical cavity surface emitting laser.

5. The system of claim 1 further comprising a database storing reference characteristics associated with objects and stored as target data and for providing access to said reference characteristics to said microprocessor.

6. The system of claim 5 wherein said laser source emits at least two laser signals into an environment occupied by a object, said at least one detector detects said at least two laser signals after said signals pass through said environment containing at least one object, and said microprocessor determines object characteristics based on comparison of said signals received by said detector with said object characteristics stored in said database.

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

2. The system of claim I further comprising a memory for further providing said system with a target-free environment and/or known target characteristic data.

3. The system of claim 2 wherein object characteristics are determined by said system based on comparison of laser signals received by said detector after interference with objects newly introduced into said environment with said target characteristics stored in said database.

8. A method for detecting the presence of an object in a monitored area using an object detection system and selectively causing a response when an object is detected, comprising the steps of:

emitting at least two laser signals into a monitored area using a vertical cavity surface emitting laser structure;

receiving any of said laser signals not blocked by said object with at least one detector;

determining the presence or absence of an object in said environment using a microprocessor, wherein an object is present where at least one of said laser signals is blocked by at least one object;

determining characteristics of said object by comparing characteristics of laser signals associated with said object received by said detector with object characteristics stored in a memory; and

selectively causing a controller response in accordance with the determination of object characteristics and correlating response criteria.

9. The method of claim 8 further comprising training an object detection system to determine object characteristics through the steps of:

emitting at least one laser signal at a time into an environment using a vertical cavity surface emitting laser structure;

at least one test object blocking at least one of said laser signals;

receiving by at least one detector laser signals not blocked by said test object, said laser signals representing object characteristics; and

storing said object characteristics in a memory.

10. The method of claim 8, wherein said microprocessor determines the size or shape of said object by determining which of said laser signals are received by said detector after different arrays of said laser signals are emitted by said vertical cavity surface emitting laser structure and subsequent comparison with object characteristics stored in memory.

11. A method for scanning a monitored area and detecting the presence of predefined targets comprising the steps of:

training a laser optic object detection system with the individually with the characteristics of known targets in an environment representing said monitored area by emitting at least one laser signal into said environment using a vertical cavity surface emitting laser structure, receiving by at least one detector laser signals reflected off of known targets, and storing signals representative of said known targets;

monitoring said environmental having known characteristics associated with an object-free environment by emitting at least one laser signal into an environment wherein at least one of said at least one laser signals is blocked by at least one object interfering with at least one of said laser signals;

detecting the presence of at least one object in said environment by receiving through at least one detector laser signals from said environment laser signal blocked by said at least one object; and

determining with a microprocessor the identification of said at least one object in said environment by comparing said known target characteristics with said at least one detector laser signals from said environment and blocked by said at least one object.

12. The method of claim 11, wherein the size, shape and/or motion of said object is determined by analyzing laser signals received by said detector after different sequences of said laser signals are emitted by said vertical cavity surface emitting laser structure.

13. The method of claim 11, 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.

14. The method of claim 11, 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.

15. The method of claim 11 wherein a control function associated with the detection and identification of said object is executed.

16. The method of claim 15 wherein said control function is to turn at least one light within said environment.

17. The method of claim 15 wherein said control function is to activate an alarm if said object is not identified.

18. The method of claim 15 wherein said control function is to activate a HVAC system associated with said environment.