Patent US4225226A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4225226A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser guidance system for crop spraying aircraft

Assignee: Trimble Inc
•
Filing: 1978-12-29
•
Granted: 1980-09-30
•
Expires: 1998-12-29
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract This invention provides a method for controlling the path of a crop spraying aircraft in making repeated traverses over a field to insure that each traverse is laterally spaced from the adjacent traverse by the proper distance to assure adequate coverage of the crop land with the material being sprayed and avoiding over-lapping or insufficient coverage of any portion of the crop land. In accordance with the method of the invention, the crop spraying aircraft carries a rotating laser beam transmitter and receiver, and the transmitted beam is reflected from a plurality of reflectors located on the ground at known positions relative to each other to provide successive reflections of the transmitted laser beam from which the angular positions of the aircraft relative to the reflectors may be continuously determined. After an initial pass over the field to establish the spray path, the position of the aircraft may be continuously computed by a microprocessor and an error signal generated during each subsequent pass to indicate to the aircraft operator whether the aircraft should be steered more to the right or left to stay on the desired spraying path.

Inventors

  • 👤 Richard W. Davidson
  • 👤 Joseph F. Rando
  • 👤 Ted L. Teach

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 22:58
CPC Classifications
G; G05; G05D; G05D1/00; G05D1/02; G05D1/0202; G01; G01S; G01S17/00; G01S17/87

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 154 words
A method of guiding crop spraying aircraft in a desired path across a field, comprising the steps of: a. locating a plurality of laser reflectors in a linear array in the vicinity of the field with a known spacing between such reflectors; b. emitting from the aircraft a laser beam, fan-shaped in a vertical plane and rotating about a vertical axis, thereby periodically traversing said reflectors; c. receiving on the aircraft the laser beams reflected from said reflectors; d. determining the angular relationship between the reflected laser beams from each successive reflector; e. continuously computing from said angular relationships the horizontal position of the aircraft relative to said reflectors; and f. continuously comparing the actual horizontal position of the aircraft with a desired horizontal position and generating signals representing any differences therebetween, whereby the aircraft can be returned to the desired horizontal position relative to said reflectors by an aircraft operator utilizing said signals.
Claim 2
Independent Claim 154 words
A method of guiding crop spraying aircraft in a desired path across a field, comprising the steps of: a. locating a plurality of laser reflectors in a linear array in the vicinity of the field with a known spacing between such reflectors; b. emitting from the aircraft a laser beam, fan-shaped in a vertical plane and rotating about a vertical axis, thereby periodically traversing said reflectors; c. receiving on the aircraft the laser beams reflected from said reflectors; d. determining the angular relationship between the reflected laser beams from each successive reflector; e. continuously computing from said angular relationships the horizontal position of the aircraft relative to said reflectors; and f. continuously comparing the actual horizontal position of the aircraft with a desired horizontal position and generating signals representing any differences therebetween, whereby the aircraft can be returned to the desired horizontal position relative to said reflectors by an aircraft operator utilizing said signals.
Claim 3
Dependent Claim 25 words
The method of claim 1 wherein said reflectors are disposed in a line parallel to the desired traverse paths of the plane over the field.
Claim 4
Dependent Claim 29 words
The method of claim 1 including the step of making an initial pass across the field to establish the initial horizontal position of the aircraft relative to said reflectors.
Claim 5
Dependent Claim 24 words
The method of claim 3 including the step of computing at least one desired horizontal position for said aircraft from said initial horizontal position.

References Cited (Backward Citations)

US3000256A Cited
GB1181162A Cited
US3530468A Cited
US3671963A Cited
US3620626A Cited
US3711203A Cited
US3698816A Cited
US3687556A Cited
US3788748A Cited
US3897151A Cited
US4123165A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-09-30 1984-03-31 1984-09-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-09-30 1988-03-31 1988-09-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-09-30 1992-03-31 1992-09-30 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag