Hyperacuity system and methods for real time and analog detection and kinematic state tracking

• US 10,366,506 B2
• Filed: 11/06/2015
• Issued: 07/30/2019
• Est. Priority Date: 11/07/2014
• Status: Active Grant

• Current Assignee: Lamina Systems, Inc.
• Original Assignee: Lamina Systems, Inc.
• Inventors: Unglaub, Ricardo A. G., Wilcox, Michael, Swanson, Paul, Odell, Chris
• Primary Examiner(s): Torrente, Richard T
• Application Number:
  US14/935,352
• Publication Number:
  US 20160134806A1
• Time in Patent Office: 1,362 Days
• Field of Search: 348 43
• CPC Class Codes: G06T 2207/10052 Images from lightfield camera
• CPC Class Codes: G06T 3/4053 based on super-resolution, i.e. the output image resolution being higher than the sensor resolution
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: G06T 7/73 using feature-based methods

Abstract

Methods and systems described herein determine a location of a tracked object with respect to a coordinate system of a sensor array by using analog signals from sensors having overlapping nonlinear responses. Hyperacuity and real time tracking are achieved by either digital or analog processing of the sensor signals. Multiple sensor arrays can be configured in a plane, on a hemisphere or other complex surface to act as a single sensor or to provide a wide field of view and zooming capabilities of the sensor array. The processing methods can be used to adjust to contrast reversals between an image and the background.

Claims

1. A method of calculating a position of a feature of an object at hyperacuity accuracy, the method comprising:

receiving output signals from a plurality of sensors, wherein the plurality of sensors;

are configured in an array;

have overlapping spatial response profiles, wherein for each of the plurality of sensors, the spatial response profile is non-linear and is axio-symmetric about a respective center of the sensor; and

produce the output signals based on the spatial response profiles;

generating logarithmically amplified output signals by applying logarithmic amplification to each output signal;

multiplying the amplified output signals by predefined constants that are based on;

distances between each of the plurality of sensors and a physical origin of the array; and

a rate of response decay of each of the plurality of sensors; and

determining coordinates of the position of the feature with respect to the physical origin of the array by summing the logarithmically amplified output signals.

2. The method of claim 1 wherein the non-linear spatial response profiles of the sensors have an approximately Gaussian profile.

3. The method of claim 1 wherein determining the coordinates of the position of the feature with respect to the physical origin of the array comprises using a linear combination of the logarithmically amplified output signals of at least three sensors, at least two of the at least three sensors being adjacent.

4. The method of claim 1 further comprising determining at least one of a velocity and an acceleration of the feature by calculating time-derivatives of the position of the feature.

5. The method of claim 1 wherein:

the sensors are optical sensors arranged on a focal plane of an objective lens;

the feature is a component of a focused image of the object; and

processing of the output signals is performed with analog circuitry in real time.

6. The method of claim 5 wherein:

the array comprises six optical sensors that are arranged hexagonally around a central optical sensor; and

the physical origin of the array is a center of the central optical sensor.

7. The method of claim 5, further comprising determining positions of a plurality of dependent or independent features, wherein independent features comprise focused images of respective objects, wherein a quantity of features in the plurality of features is at most one less than a total number of the optical sensors, and wherein the determination of the positions of the features uses at least the logarithmically amplified output signal of a central optical sensor and of another optical sensor.

8. A tracking system for determining a position of a feature of an object at hyperacuity accuracy, the tracking system comprising:

an array comprising a plurality of sensors, wherein for each of the plurality of sensors a spatial response profile is non-linear and is axio-symmetric about a respective center of the sensor, and the sensor produces an output signal based on the spatial response profile; and

components configured to receive the output signals from the sensors, wherein, in response to receiving the output signals from the sensors, the components process the received output signals by;

generating logarithmically amplified output signals by applying logarithmic amplification to each output signal;

multiplying the amplified output signals by predefined constants that are based on;

distances between each of the plurality of sensors and a physical origin of the array; and

a rate of response decay of each of the plurality of sensors; and

determining coordinates of the position of the feature with respect to the physical origin of the array by summing the logarithmically amplified output signals.

9. The tracking system of claim 8, wherein:

the plurality of sensors are optical sensors arranged on a focal plane of an objective lens;

each of the optical sensors is configured with a respective sensor lens, so that the objective lens and the respective sensor lens of each optical sensor are arranged to produce the non-linear spatial response profile of the optical sensor; and

the feature is a component of a focused image of the object.

10. The tracking system of claim 8 wherein:

the non-linear spatial response profiles of the plurality of sensors have an approximately Gaussian profile.

11. The tracking system of claim 8 wherein:

processing of the output signals is performed with analog circuitry in real time; and

wherein determining the coordinates of the position of the feature with respect to the physical origin of the array comprises using a linear combination of the logarithmically amplified output signals of at least three sensors, at least two of the at least three sensors being adjacent.

12. A method of calculating positions of features of an object at hyperacuity accuracy, the method comprising:

receiving output signals from a plurality of sensors, wherein the plurality of sensors;

are configured in an array;

have overlapping spatial response profiles, wherein for each of the plurality of sensors, the spatial response profile is non-linear and is axio-symmetric about a respective center of the sensor; and

produce output signals based on the spatial response profiles; and

processing the signals by;

applying logarithmic amplification to each output signal; and

determining positions of a plurality of dependent or independent features with respect to a physical origin of the array using a linear combination of the logarithmically amplified output signals, wherein;

the independent features comprise focused images of respective objects;

a quantity of features in the plurality of features is at most one less than a total number of the plurality of sensors; and

determining the positions of the features uses at least two of the logarithmically amplified output signals comprising the logarithmically amplified output signals of a central sensor and of another sensor in the plurality of sensors.

13. The method of claim 12 wherein the non-linear spatial response profiles of the sensors have an approximately Gaussian profile.

14. The method of claim 12 wherein determining the positions of the features with respect to the physical origin of the array comprises using a linear combination of the logarithmically amplified output signals of at least three sensors, at least two of the at least three sensors being adjacent.

15. The method of claim 12 further comprising determining at least one of a velocity and an acceleration of each of the plurality of features by calculating time-derivatives of the positions of each of the plurality of features.

16. The method of claim 12 wherein:

the plurality of sensors are optical sensors arranged on a focal plane of an objective lens;

each feature is a component of a focused image of the object; and

processing of the output signals is performed with analog circuitry in real time.

17. The method of claim 16 wherein:

the array comprises six optical sensors that are arranged hexagonally around a central optical sensor; and

the physical origin of the array is a center of the central optical sensor.