← Back to Patent Explorer
US5647015A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of inferring sensor attitude through multi-feature tracking

Assignee: Texas Instruments Inc
•
Filing: 1995-06-07
•
Granted: 1997-07-08
•
Expires: 2015-06-07
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method for inferring precise sensor attitude information in a tracking sensor system begins with storing at a first time a reference image in a memory associated with tracking sensor. Next, the method includes sensing at a second time a second image. The sensed image comprises a plurality of sensed feature locations. The method further includes determining the position of the tracking sensor at the second time relative to its position at the first time and then forming a correlation between the sensed feature locations and the predetermined feature locations as a function of the relative position. The method results in an estimation of a tracking sensor pose that is calculated as a function of the correlation. Because the method is primarily computational, implementation requires no new hardware in a tracking sensor system other than that which may be required to provide additional computational capacity.

Inventors

  • 👤 William Clay Choate
  • 👤 Rajendra K. Talluri

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 19:32
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/41; G01S7/411; G01C; G01C21/00; G01C21/005; G01S3/00; G01S3/78; G01S3/782; G01S3/785; G01S3/786; G01S3/7864; G01S5/00; G01S5/16; G01S5/163; G06; G06T; G06T7/00; G06T7/70; G06T7/73; G06T7/97; G01S13/00; G01S13/88; G01S13/93; G01S13/933; G01S13/935

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 187 words
A method of determining attitude of a tracking sensor, said tracking sensor including a memory, comprising the steps of: storing at a first time a reference image in said memory of said tracking sensor, said reference image including a plurality of reference feature locations; sensing at a second time first image using said tracking sensor, said first image including a plurality of sensed feature locations; mapping said reference feature locations and said sensed feature locations from a world coordinate system to a canonical coordinate system using a 3-by-3 rotational matrix, S, said world coordinate system having a center of focus, p, in accordance with the equation: x'=S(x-p) where x' is a 3-vector in said world coordinate system, x is a 3-vector in said canonical coordinate system; determining relative position of said tracking sensor between said second time and said first time; correlating each of said sensed feature locations with each of said reference feature locations in said canonical coordinate system as a function of said relative position; and calculating said tracking sensor attitude as a function of said correlation to provide signals representing said tracking sensor attitude.
Claim 2
Independent Claim 187 words
A method of determining attitude of a tracking sensor, said tracking sensor including a memory, comprising the steps of: storing at a first time a reference image in said memory of said tracking sensor, said reference image including a plurality of reference feature locations; sensing at a second time first image using said tracking sensor, said first image including a plurality of sensed feature locations; mapping said reference feature locations and said sensed feature locations from a world coordinate system to a canonical coordinate system using a 3-by-3 rotational matrix, S, said world coordinate system having a center of focus, p, in accordance with the equation: x'=S(x-p) where x' is a 3-vector in said world coordinate system, x is a 3-vector in said canonical coordinate system; determining relative position of said tracking sensor between said second time and said first time; correlating each of said sensed feature locations with each of said reference feature locations in said canonical coordinate system as a function of said relative position; and calculating said tracking sensor attitude as a function of said correlation to provide signals representing said tracking sensor attitude.
Claim 3
Dependent Claim 27 words
The method of claim 1 wherein said storing step comprises the step of storing data from a correlation template of the reference image at said first time.
Claim 4
Dependent Claim 27 words
The method of claim 1, wherein said correlation forming step comprises the step of applying discrete time formulation relationship between said reference image and said second image.
Claim 5
Dependent Claim 13 words
The method of claim 1, wherein said images comprise Forward Looking Infrared images.
Claim 6
Dependent Claim 14 words
The method of claim 1, wherein said images comprises air-to-ground RF emitter location images.

References Cited (Backward Citations)

US4993662A Cited
US4324491A Cited
US4162775A Cited
US4688092A Cited
US4746976A Cited
US5155684A Cited
US4969036A Cited
US5204818A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-07-07 2001-01-06 2001-07-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-07-07 2005-01-06 2005-07-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-07-07 2009-01-06 2009-07-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag