MULTI-CHANNEL LED OBJECT DETECTION SYSTEM AND METHOD

• US 20110205521A1
• Filed: 11/18/2010
• Published: 08/25/2011
• Est. Priority Date: 12/19/2005
• Status: Active Grant

• Current Assignee: LeddarTech, Inc.
• Original Assignee: LeddarTech, Inc.
• Inventors: MIMEAULT, Yvan, GALLANT, Pascal, CANTIN, Daniel
• Granted Patent: US 8,242,476 B2
• Time in Patent Office: Days
• US Class Current: 356/4.01
• 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
• CPC Class Codes: G01S 7/4814 of transmitters alone

Abstract

A method for detecting an object located in an environment and a multi-channel LED object detection system for detecting an object located in an environment are provided. The method includes providing a Light-Emitting-Diode (LED) light source having a wide field-of-illumination and orienting the LED light source for the wide field-of-illumination to encompass the width of the environment; providing an optical detector having a wide field-of-view and orienting the optical detector for the wide field-of-view to encompass the width of the environment, the optical detector having a plurality of sub-detectors, each having an individual narrow field-of-view, each individual narrow field-of-view creating a channel in the wide field-of-view; driving the LED light source into emitting light toward the environment, the width of the environment being illuminated by the light, the light having an emitted light waveform; receiving and acquiring an individual complete trace of a reflection/backscatter of the emitted light on the object in the environment at each sub-detector of the plurality, thereby combining the individual narrow field-of-view to create the wide field-of-view encompassing the width of the environment and thereby receiving and acquiring an individual complete trace for each channel; converting the acquired individual complete trace of the reflection/backscatter into an individual digital signal; and detecting and identifying at least one of a presence of an object in the environment, a position of the object in the environment, a distance between the object and the LED light source and a visibility in the environment, using the emitted light waveform and at least one of the individual digital signal.

Claims

1. A method for detecting an object located in an environment, said environment having a width, comprising:

providing a Light-Emitting-Diode (LED) light source having a wide field-of-illumination and orienting said LED light source for said wide field-of-illumination to encompass said width of said environment;

providing an optical detector having a wide field-of-view and orienting said optical detector for said wide field-of-view to encompass said width of said environment, said optical detector having a plurality of sub-detectors, each having an individual narrow field-of-view, each individual narrow field-of-view creating a channel in said wide field-of-view;

driving the LED light source into emitting light toward the environment, said width of said environment being illuminated by said light, said light having an emitted light waveform;

receiving and acquiring an individual complete trace of a reflection/backscatter of the emitted light on the object in the environment at each sub-detector of said plurality, thereby combining said individual narrow field-of-view to create said wide field-of-view encompassing said width of said environment and thereby receiving and acquiring an individual complete trace for each channel;

converting said acquired individual complete trace of said reflection/backscatter into an individual digital signal; and

detecting and identifying at least one of a presence of an object in the environment, a position of the object in the environment, a distance between the object and the LED light source and a visibility in said environment, using said emitted light waveform and at least one of said individual digital signal.

2. The method as claimed in claim 1, wherein said providing a LED light source comprises providing an invisible LED light source and said driving said invisible LED light source comprises illuminating said environment using non-visible light for said detection.

3. The method as claimed in claim 1, wherein said providing a LED light source comprises providing a visible LED light source and said driving said visible LED light source comprises at least one of illuminating said environment using visible light for said detection and emitting a signal to a person in the environment.

4. The method as claimed in claim 1, wherein the step of driving the LED light source comprises at least one of pulsating and modulating the light.

5. The method as claimed in claim 1, wherein said providing a LED light source comprises providing at least one visible LED light source and at least one invisible LED light source and wherein said driving said LED light source comprises driving said invisible LED light source for illuminating said environment using non-visible light for said detection and driving said visible LED light source for at least one of illuminating said environment using visible light for said detection and emitting a signal to a person in the environment.

6. The method as claimed in claim 1, wherein said step of providing a LED light source comprises providing a plurality of LED light sources, each having an individual narrow field-of-illumination, wherein said step of driving the LED light source comprises driving said plurality of LED light sources to emit light in combination, thereby combining said individual narrow field-of-illumination to create said wide field-of-illumination encompassing said width of said environment.

7. The method as claimed in claim 6, wherein said driving said plurality of LED light sources includes driving said LED light sources to emit light one of in sequence and simultaneously.

8. The method as claimed in claim 1, wherein said step of detecting and identifying further comprises combining information obtained from at least two individual digital signals to detect and identify.

9. The method as claimed in claim 1, wherein said detecting and identifying said distance comprises measuring a time delay between said driving the LED light source to emit the light and said receiving said complete trace.

10. The method as claimed in claim 1, further comprising repeating said steps of driving, receiving and acquiring, converting and detecting and identifying to cumulate a plurality of time-spaced digital signals for said detector.

11. The method as claimed in claim 10, further comprising analyzing said plurality of time-spaced digital signals to determine at least one of a displacement speed of said object, a shape of said object and a dimension of said object.

12. The method as claimed in claim 1, wherein said visibility is an environmental condition, said environmental condition being a presence of one of fog, rain, snow, dust, smoke, gas, smog.

13. A multi-channel LED object detection system for detecting an object located in an environment, said environment having a width, comprising:

a Light-Emitting-Diode (LED) light source having a wide field-of-illumination oriented for said wide field-of-illumination to encompass said width of said environment;

a source controller for said LED light source for driving said LED light source into emitting light toward the environment, said width of said environment being illuminated by said light, said light having an emitted light waveform;

an optical detector having a wide field-of-view oriented for said wide field-of-view to encompass said width of said environment, said optical detector having a plurality of sub-detectors, each having an individual narrow field-of-view, each individual narrow field-of-view creating a channel in said wide field-of-view, said optical detector receiving an individual complete trace of a reflection/backscatter of the emitted light on the object in the environment at each sub-detector of said plurality, thereby combining said individual narrow field-of-view to create said wide field-of-view encompassing said width of said environment and thereby receiving and acquiring an individual complete trace for each channel;

an analog-to-digital converter for converting each said individual complete trace of said reflection/backscatter into an individual digital signal;

a memory for acquiring and storing each said individual complete trace; and

a signal processor for detecting and identifying at least one of a presence of an object in the environment, a position of the object in the environment, a distance between the object and the LED light source and a visibility in said environment, using said emitted light waveform and at least one of said individual digital signal and outputting a data output associated to the object.

14. The multi-channel LED object detection system as claimed in claim 13, wherein said LED light source is an invisible LED light source and said width of said environment is illuminated by non-visible light for said detection.

15. The multi-channel LED object detection system as claimed in claim 13, wherein said invisible LED light source is an infrared LED light source.

16. The multi-channel LED object detection system as claimed in claim 13, wherein said LED light source comprises a plurality of LED light sources, each having an individual narrow field-of-illumination, and wherein said source controller drives said plurality of LED light sources to emit light in combination, thereby combining said individual narrow field-of-illumination to create said wide field-of-illumination encompassing said width of said environment.

17. The multi-channel LED object detection system as claimed in claim 16, wherein said plurality of LED light sources is multiple small clusters of LEDs.

18. The multi-channel LED object detection system as claimed in claim 13, further comprising a lens and a diffuser, said lens for collimating the power of said light source, said diffuser for diffusing said collimated power to illuminate said environment.

19. The multi-channel LED object detection system as claimed in claim 13, wherein said plurality of optical sub-detectors is arranged in a detector array, said detector array is one of a linear array, a 2D type array, an APD array, a photodiode array, a CCD sensor and a CMOS sensor.

20. The multi-channel LED object detection system as claimed in claim 13, wherein said object is at least one of a vehicle, a truck, a boat, a car, a motorcycle, a tricycle, a bicycle, a person, a pavement, a sidewalk, a ground surface, a particle, an environmental particle, a wall, a post, a stationary object and a moving object.

21. The multi-channel LED object detection system as claimed in claim 13, wherein said wide field-of-illumination has an angular range of more than 10 degrees.

22. The multi-channel LED object detection system as claimed in claim 21, wherein said angular range of said field-of-illumination is between 15 and 180 degrees.