Sensors, systems and methods for position sensing

• US 8,928,873 B2
• Filed: 03/25/2013
• Issued: 01/06/2015
• Est. Priority Date: 09/20/2008
• Status: Active Grant

• Current Assignee: Baanto International Ltd.
• Original Assignee: Baanto International Ltd.
• Inventors: Utukuri, Avanindra, Clarke, Jonathan
• Primary Examiner(s): STAFIRA, MICHAEL PATRICK
• Application Number:
  US13/850,204
• Publication Number:
  US 20140055778A1
• Time in Patent Office: 652 Days
• US Class Current: 356/138
• CPC Class Codes: G01J 1/4257 applied to monitoring the characteristics of a beam, e.g. laser beam, headlamp beam monitoring arrangements for lasers in general H01S3/0014
• CPC Class Codes: G01S 3/782 Systems for determining direction or deviation from predetermined direction
• CPC Class Codes: G01S 3/784 using a mosaic of detectors
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves

Abstract

Various systems and methods for estimating the position of a radiation source in three-dimensional space, together with sensors for use in such systems are described. In some embodiments, the systems include a plurality of radiation sensors. The three-dimensional position of the radiation source is estimated relative to each sensor using an aperture that casts shadows on a radiation detector as a function of the incident angle of the incoming radiation. In some embodiments, the ratio of a reference radiation intensity to a measured radiation intensity is used to estimate direction of the radiation source relative to the sensor. When the angular position of the radiation source is estimated relative to two sensors, the position of the radiation source in three dimensions can be triangulated based on the known relative positions of the two sensors.

Claims

1. A system for estimating the position of a radiation source in three dimensional space, the system comprising:

a first radiation sensor for receiving radiation from the radiation source and for providing a first incident angle pair corresponding to the direction of the radiation source relative to the first radiation sensor, wherein the first radiation sensor includes;

a first reference radiation detector for providing a first reference radiation intensity signal corresponding to an intensity of radiation incident on the first reference radiation detector;

a first direction radiation detector for providing a first direction radiation intensity signal corresponding to an intensity of radiation incident on the first direction radiation detector;

a second direction radiation detector for providing a second direction radiation intensity signal corresponding to an intensity of radiation incident on the second direction radiation detector; and

a first radiation stop for partially blocking radiation from reaching the first and second direction radiation detectors; and

a second radiation sensor for receiving radiation from the radiation source and for providing a second incident angle pair corresponding the direction of the radiation source relative to the second radiation sensor, wherein the second radiation sensor includes;

a second reference radiation detector for providing a second reference radiation intensity signal corresponding to an intensity of radiation incident on the second reference radiation detector;

a third direction radiation detector for providing a third direction radiation intensity signal corresponding to an intensity of radiation incident on the third direction radiation detector;

a fourth direction radiation detector for providing a fourth direction radiation intensity signal corresponding to an intensity of radiation incident on the fourth direction radiation detector;

a second radiation stop for partially blocking radiation from reaching the third and fourth direction radiation detectors; and

a processor for calculating the estimated position of the radiation source based on the first and second incident angle pairs, wherein;

the processor is coupled to the first reference radiation detector and to the first and second direction radiation detectors for providing first and second incident angles wherein;

the first incident angle corresponds to the first direction radiation intensity signal and the first reference radiation intensity signal;

the second incident angle corresponds to the second direction radiation intensity signal and the first reference radiation intensity signal; and

the first and second incident angles form the first incident angle pair;

the processor is coupled to the second reference radiation detector and to the third and fourth direction radiation detectors for providing third and fourth incident angles wherein;

the third incident angle corresponds to the third direction radiation intensity signal and the second reference radiation intensity signal;

the fourth incident angle corresponds to the fourth direction radiation intensity signal and the second reference radiation intensity signal; and

the third and fourth incident angles form the second incident angle pair.

2. The system of claim 1 wherein the processor is adapted to calculate the estimated position of the radiation source by determining a point of intersection between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

3. The system of claim 1 wherein the processor is adapted to calculate the estimated position of the radiation source by identifying a line segment between the closest points between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

4. The system of claim 3 wherein the processor is adapted to calculate the estimate position of the radiation source by bisecting the line segment.

5. The system of claim 4 wherein the first and second radiation sensors are mounted in a fixed relationship to one another.

6. A system for estimating the position of a radiation source in three dimensional space, the system comprising:

a first radiation sensor for receiving radiation from the radiation source and for providing a first incident angle corresponding to the direction of the radiation source relative to the first radiation sensor, wherein the first radiation sensor includes;

a first reference radiation detector for providing a first reference radiation intensity signal corresponding to an intensity of radiation incident on the first reference radiation detector;

a first pair of directional radiation detectors for providing a pair of first directional radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the first pair of directional radiation detectors; and

a first radiation stop for partially blocking radiation from reaching the first directional radiation detectors; and

a second radiation sensor for receiving radiation from the radiation source and for providing a second incident angle corresponding to the direction of the radiation source relative to the second radiation sensor, wherein the second radiation sensor includes;

a second reference radiation detector for providing a second reference radiation intensity signal corresponding to an intensity of radiation incident on the second reference radiation detector;

a second pair of directional radiation detectors for providing a pair of second directional radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the second pair of directional radiation detectors;

a second radiation stop for partially blocking radiation from reaching the second directional radiation detectors; and

a processor for calculating the estimated position of the radiation source based on the first and second incident angles, wherein;

the processor is coupled to the first reference radiation detector and to the first pair of directional radiation detectors for providing the first incident angle wherein the first incident angle corresponds to the pair of first directional radiation intensity signals;

the processor is coupled to the second reference radiation detector and to second pair of directional radiation detectors for providing the second incident angle wherein the second incident angle corresponds to pair of second directional radiation intensity signals.

7. The system of claim 6 wherein the processor is adapted to calculate the estimated position of the radiation source by determining a point of intersection between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

8. The system of claim 6 wherein the processor is adapted to calculate the estimated position of the radiation source by identifying a line segment between the closest points between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

9. The system of claim 8 wherein the processor is adapted to calculate the estimate position of the radiation source by bisecting the line segment.

10. The system of claim 9 wherein the first and second radiation sensors are mounted in a fixed relationship to one another.

11. The system of claim 9 wherein the first and second sensors are independently positionable.

12. A system for estimating the position of a radiation source in three dimensional space, the system comprising:

a first radiation sensor for receiving radiation from the radiation source and for providing a first incident angle pair corresponding to the direction of the radiation source relative to the first radiation sensor, wherein the first radiation sensor includes;

a first reference radiation detector for providing a first reference radiation intensity signal corresponding to an intensity of radiation incident on the first reference radiation detector;

a pair of first direction radiation detectors for providing a pair of first direction radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the first direction radiation detectors;

a pair of second direction radiation detectors for providing a pair of second direction radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the second direction radiation detectors; and

a first radiation stop for partially blocking radiation from reaching the first and second direction radiation detectors; and

a second radiation sensor for receiving radiation from the radiation source and for providing a second incident angle pair corresponding the direction of the radiation source relative to the second radiation sensor, wherein the second radiation sensor includes;

a second reference radiation detector for providing a second reference radiation intensity signal corresponding to an intensity of radiation incident on the second reference radiation detector;

a pair of third direction radiation detectors for providing a pair of third direction radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the third direction radiation detectors;

a pair of fourth direction radiation detectors for providing a pair of fourth direction radiation intensity signals corresponding respectively to an intensity of radiation incident on each of the fourth direction radiation detectors; and

a second radiation stop for partially blocking radiation from reaching the third and fourth direction radiation detectors; and

a processor for calculating the estimated position of the radiation source based on the first and second incident angle pairs, wherein;

the processor is coupled to the first reference radiation detector and to the first and second direction radiation detectors for providing first and second incident angles wherein;

the first incident angle corresponds to the first direction radiation intensity signals and the first reference radiation intensity signal;

the second incident angle corresponds to the second direction radiation intensity signals and the first reference radiation intensity signal; and

the first and second incident angles form the first incident angle pair;

the processor is coupled to the second reference radiation detector and to the third and fourth direction radiation detectors for providing third and fourth incident angles wherein;

the third incident angle corresponds to the third direction radiation intensity signals and the second reference radiation intensity signal;

the fourth incident angle corresponds to the fourth direction radiation intensity signals and the second reference radiation intensity signal; and

the third and fourth incident angles form the second incident angle pair.

13. The system of claim 12 wherein the processor is adapted to calculate the estimated position of the radiation source by determining a point of intersection between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

14. The system of claim 12 wherein the processor is adapted to calculate the estimated position of the radiation source by identifying a line segment between the closest points between a first line defined by the first incident angle pair and the position of the first radiation sensor and a second line defined by the second incident angle pair and the second radiation sensor.

15. The system of claim 14 wherein the processor is adapted to calculate the estimate position of the radiation source by bisecting the line segment.

16. The system of claim 15 wherein the first and second radiation sensors are mounted in a fixed relationship to one another.

17. The system of claim 15 wherein the first and second sensors are independently positionable.