Detecting objects based on reflectivity fingerprints

Patent metadata

Field	Value
Publication number	US-10776639-B2
Application number	US-201916456942-A
Country	US
Kind code	B2
Filing date	Jun 28, 2019
Priority date	Jan 3, 2017
Publication date	Sep 15, 2020
Grant date	Sep 15, 2020

Abstract

A LIDAR system for detecting a vehicle may include a processor configured to: scan a field of view (FOV) by controlling movement of at least one deflector at which at least one light source is directed; receive from at least one sensor signals indicative of light reflected from a particular object in the FOV; detect, based on time of flight in the received signals, portions of the particular object in the FOV that are similarly spaced from the light source; determine, based on the detected portions, at least a first portion having a first reflectivity corresponding to a license plate, and at least two additional spaced-apart portions corresponding to locations on the particular object other than a location of the first portion; and based on a spatial relationship and a reflectivity relationship between the first portion and the at least two additional portions, classify the particular object as a vehicle.

First claim

What is claimed is:

1. A LIDAR system for detecting a vehicle based on license plate reflectivity, the system comprising:
at least one processor configured to:
scan a field of view by controlling movement of at least one deflector at which at least one light source is directed;
receive from at least one sensor signals indicative of light reflected from a particular object in the field of view;
determine, times of flight in the received signals;
detect, based on the times of flight in the received signals, portions of the particular object in the field of view that have a substantially same distance from the light source;
determine, based on the detected portions, at least a first portion having a first reflectivity corresponding to a license plate, and at least two additional spaced-apart portions corresponding to locations on the particular object other than a location of the first portion, and wherein the at least two additional portions have reflectivity substantially lower than the first reflectivity; and
classify the particular object as a vehicle, based on a spatial relationship and a reflectivity relationship between the first portion and the at least two additional portions.

2. The LIDAR system of claim 1 , wherein the at least one processor is further configured to control the at least one light source in a manner enabling light flux of light projected from the at least one light source to vary during scanning of the field of view.

3. The LIDAR system of claim 2 , wherein the at least one processor is further configured to control the at least one light source in a manner enabling modulating the projected light and distinguishing between light reflected from objects in the field of view and light emitted by objects in the field of view.

4. The LIDAR system of claim 1 , wherein the at least one processor is further configured to determine a distance to the particular object and to classify the particular object based on the determined distance and the spatial relationship between the first portion and the at least two additional portions.

5. The LIDAR system of claim 1 , wherein the at least one processor is further configured to determine an angle of at least one surface associated with the particular object and to classify the particular object further based on the determined angle and the reflectivity relationship between the first portion and the at least two additional portions.

6. The LIDAR system of claim 1 , wherein the at least one processor is further configured to determine confidence scores for the reflectivity of the first portion and for the at least two additional portions and to classify the particular object further based on the determined confidence level and the reflectivity relationship between the first portion and the at least two additional portions.

7. The LIDAR system of claim 1 , wherein the at least one processor is further configured to determine distances of the first portion and the at least two additional portions of the particular object, and to account for determined distances when classifying the particular object.

8. The LIDAR system of claim 1 , wherein upon classifying the particular object as a vehicle, the at least one processor is further configured to direct more light in a subsequent scanning cycle towards the particular object.

9. The LIDAR system of claim 1 , wherein the at least one processor is further configured to classify at least one additional object as being an object other than a vehicle, based on a determined reflectivity fingerprint of the at least one additional object.

10. The LIDAR system of claim 1 , wherein the at least one processor is further configured to:
determine a reflectivity fingerprint of the particular object based on the reflectivity of the detected portions;
access memory that stores a plurality of indicators of fingerprints of various objects;
compare the reflectivity fingerprint of the particular object with the indicators of fingerprints of various objects stored in memory to identify a match; and
determine a type of the vehicle based on the identified match.

11. A vehicle, comprising:
a body; and
at least one processor within the body and configured to:
scan a field of view by controlling movement of at least one deflector at which at least one light source is directed;
receive, from at least one sensor, reflections signals indicative of light reflected from a particular object in the field of view;
determine, times of flight in the received signals;
detect, based on the times of flight, portions of the particular object in the field of view that have a substantially same distance from the light source;
identify, based on the detected portions, at least a first portion having a first reflectivity, a second portion having a second reflectivity, and a third portion having a third reflectivity, and wherein the at least second and third portions have reflectivity substantially lower than the first reflectivity;
determine a reflectivity fingerprint of the particular object based on a reflectivity relationship between the first portion, the second portion, and the third portion; and
classify the particular object based on the determined reflectivity fingerprint of the particular object.

12. The vehicle of claim 11 , wherein the at least one processor is further configured to classify a plurality of objects within the field of view, and to distinguish between the plurality of objects based on a unique reflectivity fingerprint associated with each of the plurality of objects.

13. The vehicle of claim 11 , wherein the at least one processor is further configured to determine a distance of the particular object and to account for the determined distance when determining the reflectivity fingerprint of the particular object.

14. The vehicle of claim 11 , wherein the at least one processor is further to configured to enable construction of a 3D map of an environment around the vehicle, the 3D map including data representative of a reflectivity of objects in the field of view.

15. The vehicle of claim 11 , wherein the at least one processor is further configured to determine a confidence score for the determined reflectivity fingerprint and to consider the determined confidence when classifying the particular object.

16. The vehicle of claim 11 , wherein the vehicle is at least partially autonomous and the at least one processor is further configured to cause a change in an operation of the vehicle based on a type of the particular object.

17. The vehicle of claim 11 , wherein the at least one processor is further configured to control the at least one light deflector such that during a scanning cycle of the field of view, the at least one light deflector instantaneously assumes a plurality of instantaneous positions.

18. The vehicle of claim 17 , wherein the at least one processor is configured to coordinate the at least one light deflector and the at least one light source such that when the at least one light deflector assumes a particular instantaneous position, a portion of a light beam is deflected by the at least one light deflector from the at least one light source towards an object in the field of view, and reflections of the portion of the light beam from the object are deflected by the at least one light deflector toward at least one sensor.

19. The vehicle of claim 17 , further comprising a plurality of light sources aimed at the at least one light deflector, wherein the at least one processor is further configured to control the at least

Assignees

• Innoviz Tech Ltd

Inventors

• Steinberg Amit
• Elooz David
• Keilaf Omer David
• Buskila Oren
• Rosenzweig Oren

Classifications

• G06V20/625

  License plates · CPC title

• G06V10/60

  relating to illumination properties, e.g. using a reflectance or lighting model · CPC title

• G06V10/82

  using neural networks · CPC title

• G06F18/2414

  Smoothing the distance, e.g. radial basis function networks [RBFN] · CPC title

• G06F18/24

  Classification techniques · CPC title