Position sensing system for surveying and grading

Claim 1

A position sensing apparatus comprising: a first energy beam transmitter operable for projecting a first energy beam that sweeps in a plane across an area in which position sensing is to occur; first reference signal means for generating a first reference signal when said first energy beam is aligned with a first reference line; a second energy beam transmitter operable for projecting a second energy beam that sweeps in a plane across said area, wherein said first and second energy beam transmitters are positioned apart; second reference signal means for generating a second reference signal when said second energy beam is aligned with a second reference line; an energy beam receiver operable for detecting said first and second energy beams, wherein said energy beam receiver is placed at a location at which the position is to be determined; a reference signal receiver operable for receiving said first and second reference signals; and processing means coupled to said energy beam and reference signal receivers and responsive to the timing of the detection of said energy beams relative to the receipt of said reference signals for determining the position of said energy beam receiver relative to said reference lines and said energy beam transmitters.

Claim 27

An apparatus comprising: first and second reference stations positioned apart at known locations during position sensing operations utilizing said apparatus, wherein each reference station includes a laser beam transmitter that projects a laser beam that periodically sweeps at a constant angular velocity in a plane across an area in which position sensing is to occur and that periodically strikes the other reference station and a portable receiver, includes a detector for detecting the laser beam from the other laser beam transmitter, and includes a radio transmitter coupled to said detector for broadcasting a reference signal upon each detection of the other laser beam by said detector, and wherein one of said laser beams is a datum laser beam that defines a datum plane; a portable receiver that is placed at a location at which the position is to be determined, wherein said portable receiver includes a laser beam receiver operable for detecting the two laser beams, includes a radio receiver operable for receiving the two reference signals, and includes means for measuring the height at which said datum laser beam strikes said laser beam receiver; and processing means coupled to said portable receiver and responsive to the timing of the detection of said laser beams by said laser beam receiver relative to the receipt of said reference signals by said radio receiver for determining the position in said datum plane of said portable receiver relative to the locations of said laser beam transmitters, and responsive to the height measured by said laser beam receiver for determining the elevation of each location relative to said datum plane.

Claim 28

An apparatus comprising: first and second reference stations positioned apart at known locations during position sensing operations utilizing said apparatus, wherein each reference station includes a laser beam transmitter that projects a laser beam that periodically sweeps at a constant angular velocity in a plane across an area in which position sensing is to occur and that periodically strikes the other reference station and a portable receiver, includes a detector for detecting the laser beam from the other laser beam transmitter, and includes a radio transmitter coupled to said detector for broadcasting a reference signal upon each detection of the other laser beam by said detector, and wherein one of said laser beams is a datum laser beam that defines a datum plane; a portable receiver that is placed at a location at which the position is to be determined, wherein said portable receiver includes a laser beam receiver operable for detecting the two laser beams, includes a radio receiver operable for receiving the two reference signals, and includes means for measuring the height at which said datum laser beam strikes said laser beam receiver; and processing means coupled to said portable receiver and responsive to the timing of the detection of said laser beams by said laser beam receiver relative to the receipt of said reference signals by said radio receiver for determining the position in said datum plane of said portable receiver relative to the locations of said laser beam transmitters, and responsive to the height measured by said laser beam receiver for determining the elevation of each location relative to said datum plane.

Claim 40

An apparatus for positioning markers at one or more locations to be marked, said apparatus comprising: a first energy beam transmitter operable for projecting a first energy beam that sweeps in a plane across the area to be marked; first reference signal means for generating a first reference signal when said first energy beam is aligned with a first reference line; a second energy beam transmitter operable for projecting a second energy beam that sweeps in a plane across the area to be marked, wherein said first and second energy beam transmitters are positioned apart during a marking operation; second reference signal means for generating a second reference signal when said second energy beam is aligned with a second reference line; an energy beam receiver operable for detecting said first and second energy beams, wherein said energy beam receiver is sequentially positioned at each location to be marked; a reference signal receiver operable for receiving said first and second reference signals; processing means coupled to said energy beam and reference signal receivers and responsive to the timing of the detection of said energy beams relative to the receipt of said reference signals for determining the position of said energy beam receiver relative to said energy beam transmitters; data base means coupled to said processing means for defining the positions relative to said energy beam transmitters of the locations to be marked; and position error means coupled to said processing means for indicating a positional error of said energy beam receiver relative to a location to be marked, wherein the position of said energy beam receiver defines the location to be marked when said positional error is substantially equal to zero.

Claim 41

An apparatus for positioning markers at one or more locations to be marked, said apparatus comprising: a first energy beam transmitter operable for projecting a first energy beam that sweeps in a plane across the area to be marked; first reference signal means for generating a first reference signal when said first energy beam is aligned with a first reference line; a second energy beam transmitter operable for projecting a second energy beam that sweeps in a plane across the area to be marked, wherein said first and second energy beam transmitters are positioned apart during a marking operation; second reference signal means for generating a second reference signal when said second energy beam is aligned with a second reference line; an energy beam receiver operable for detecting said first and second energy beams, wherein said energy beam receiver is sequentially positioned at each location to be marked; a reference signal receiver operable for receiving said first and second reference signals; processing means coupled to said energy beam and reference signal receivers and responsive to the timing of the detection of said energy beams relative to the receipt of said reference signals for determining the position of said energy beam receiver relative to said energy beam transmitters; data base means coupled to said processing means for defining the positions relative to said energy beam transmitters of the locations to be marked; and position error means coupled to said processing means for indicating a positional error of said energy beam receiver relative to a location to be marked, wherein the position of said energy beam receiver defines the location to be marked when said positional error is substantially equal to zero.

Claim 56

An apparatus for sensing the position and elevation of a grading implement mounted on an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the earth-moving vehicle and attached grading implement to produce a desired graded surface at that position, said apparatus comprising: a first energy beam transmitter operable for projecting a first energy beam that sweeps in a plane across the area to be graded and forms a datum plane; first reference signal means for generating a first reference signal when said first energy beam is aligned with a first reference line; a second energy beam transmitter operable for projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beam transmitters are positioned apart during operation of said apparatus; second reference signal means for generating a second reference signal when said second energy beam is aligned with a second reference line; an energy beam receiver operable for detecting said first and second energy beams and for detecting the height at which said first energy beam strikes said energy beam receiver, wherein said energy beam receiver is coupled to a grading implement of an earth-moving vehicle for movement therewith; a reference signal receiver operable for receiving said first and second reference signals; and processing means coupled to said energy beam receiver and said reference signal receiver and responsive to the timing of the detection of said energy beams relative to the receipt of the respective reference signals for determining the position of the earth-moving vehicle relative to said energy beam transmitters, and responsive to the height at which said first energy beam strikes said energy beam receiver for determining the elevation of the grading implement, wherein said processing means includes data base means for defining the desired elevation of the grading implement as a function of the position of the earth-moving vehicle, and includes computational means for determining the elevation error of the grading implement according to the difference between the measured and desired elevations thereof.

Claim 57

An apparatus for sensing the position and elevation of a grading implement mounted on an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the earth-moving vehicle and attached grading implement to produce a desired graded surface at that position, said apparatus comprising: a first energy beam transmitter operable for projecting a first energy beam that sweeps in a plane across the area to be graded and forms a datum plane; first reference signal means for generating a first reference signal when said first energy beam is aligned with a first reference line; a second energy beam transmitter operable for projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beam transmitters are positioned apart during operation of said apparatus; second reference signal means for generating a second reference signal when said second energy beam is aligned with a second reference line; an energy beam receiver operable for detecting said first and second energy beams and for detecting the height at which said first energy beam strikes said energy beam receiver, wherein said energy beam receiver is coupled to a grading implement of an earth-moving vehicle for movement therewith; a reference signal receiver operable for receiving said first and second reference signals; and processing means coupled to said energy beam receiver and said reference signal receiver and responsive to the timing of the detection of said energy beams relative to the receipt of the respective reference signals for determining the position of the earth-moving vehicle relative to said energy beam transmitters, and responsive to the height at which said first energy beam strikes said energy beam receiver for determining the elevation of the grading implement, wherein said processing means includes data base means for defining the desired elevation of the grading implement as a function of the position of the earth-moving vehicle, and includes computational means for determining the elevation error of the grading implement according to the difference between the measured and desired elevations thereof.

Claim 69

A method comprising the steps of: projecting first and second energy beams from two transmitters that are spaced apart, wherein each of said energy beams periodically sweeps in a plane across an area within which position sensing is to occur; generating a first reference signal when said first energy beam is aligned with a first reference line; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams with an energy beam receiver that is placed at a location at which the position is to determined; receiving said first and second reference signals by a reference signal receiver; and determining the position of said energy beam receiver relative to said reference lines and said transmitters according to the timing of detection of said energy beams by said energy beam receiver relative to the reception of said reference signals by said reference signal receiver.

Claim 70

A method comprising the steps of: projecting first and second energy beams from two transmitters that are spaced apart, wherein each of said energy beams periodically sweeps in a plane across an area within which position sensing is to occur; generating a first reference signal when said first energy beam is aligned with a first reference line; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams with an energy beam receiver that is placed at a location at which the position is to determined; receiving said first and second reference signals by a reference signal receiver; and determining the position of said energy beam receiver relative to said reference lines and said transmitters according to the timing of detection of said energy beams by said energy beam receiver relative to the reception of said reference signals by said reference signal receiver.

Claim 87

A method for positioning markers at one or more locations to be marked, said method comprising the steps of: projecting first and second energy beams from two respective transmitters that are spaced apart at known positions, wherein each of said energy beams periodically sweeps in a plane across the area to be marked; defining the positions relative to said transmitters of the locations to be marked; generating a first reference signal when said first energy beam is aligned with a first reference line; generating a second reference signal when said second energy beam is aligned with a second reference line; positioning an energy beam receiver near a location to be marked; detecting said first and second energy beams with said energy beam receiver and receiving said first and second reference signals with a reference signal receiver; determining the position of said energy beam receiver relative to said transmitters according to the timing of detection of said energy beams by said energy beam receiver relative to the reception of said reference signals by said reference signal receiver; indicating a positional error of said energy beam receiver relative to the location to be marked; repositioning said energy beam receiver until said positional error is substantially equal to zero; and marking the position of said energy beam receiver when said positional error is substantially equal to zero.

Claim 88

A method for positioning markers at one or more locations to be marked, said method comprising the steps of: projecting first and second energy beams from two respective transmitters that are spaced apart at known positions, wherein each of said energy beams periodically sweeps in a plane across the area to be marked; defining the positions relative to said transmitters of the locations to be marked; generating a first reference signal when said first energy beam is aligned with a first reference line; generating a second reference signal when said second energy beam is aligned with a second reference line; positioning an energy beam receiver near a location to be marked; detecting said first and second energy beams with said energy beam receiver and receiving said first and second reference signals with a reference signal receiver; determining the position of said energy beam receiver relative to said transmitters according to the timing of detection of said energy beams by said energy beam receiver relative to the reception of said reference signals by said reference signal receiver; indicating a positional error of said energy beam receiver relative to the location to be marked; repositioning said energy beam receiver until said positional error is substantially equal to zero; and marking the position of said energy beam receiver when said positional error is substantially equal to zero.

Claim 91

A method for sensing the position and elevation of a grading implement of an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the grading implement to produce a desired graded surface at that position, and wherein the elevation error is the difference between the actual and desired elevations of the grading implement, said method comprising the steps of: defining the desired elevations of the grading implement as a function of the position of the grading implement throughout an area to be graded; projecting a first energy beam that sweeps in a datum plane across the area to be graded; generating a first reference signal when said first energy beam is aligned with a first reference line; projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beams are transmitted from transmitters that are positioned apart; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams by an energy beam receiver that is coupled to a grading implement of an earth-moving vehicle for movement therewith; receiving said first and second reference signals by a reference signal receiver that is coupled to the earth-moving vehicle for movement therewith; determining the position of the grading implement relative to said transmitters according to the timing of the detection of said energy beams relative to the reception of said reference signals; measuring the elevation of the grading implement according to the height at which said first energy beam strikes said energy beam receiver; and determining the elevation error of the grading implement according to the difference between the measured elevation and the desired elevation thereof.

Claim 92

A method for sensing the position and elevation of a grading implement of an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the grading implement to produce a desired graded surface at that position, and wherein the elevation error is the difference between the actual and desired elevations of the grading implement, said method comprising the steps of: defining the desired elevations of the grading implement as a function of the position of the grading implement throughout an area to be graded; projecting a first energy beam that sweeps in a datum plane across the area to be graded; generating a first reference signal when said first energy beam is aligned with a first reference line; projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beams are transmitted from transmitters that are positioned apart; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams by an energy beam receiver that is coupled to a grading implement of an earth-moving vehicle for movement therewith; receiving said first and second reference signals by a reference signal receiver that is coupled to the earth-moving vehicle for movement therewith; determining the position of the grading implement relative to said transmitters according to the timing of the detection of said energy beams relative to the reception of said reference signals; measuring the elevation of the grading implement according to the height at which said first energy beam strikes said energy beam receiver; and determining the elevation error of the grading implement according to the difference between the measured elevation and the desired elevation thereof.

Claim 103

A method for sensing the position and elevation of a grading implement of an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the grading implement to produce a desired graded surface at that position, and wherein the elevation error is the difference between the actual and desired elevations of the grading implement, said method comprising the steps of: selecting a plurality of elevation-defining line segments along which the desired contour of the land has a constant slope, wherein each line segment has end points at which the position and desired elevation is known; projecting a first energy beam that sweeps in a datum plane across the area to be graded, wherein all elevations are defined relative to said datum plane; generating a first reference signal when said first energy beam is aligned with a first reference line; projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beams are transmitted from transmitters that are positioned apart at known positions relative to said elevation-defining line segments; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams by an energy beam receiver that is coupled to a grading implement of an earth-moving vehicle for movement therewith; receiving said first and second reference signals by a reference signal receiver that is coupled to the earth-moving vehicle for movement therewith; determining the position of the grading implement relative to said transmitters according to the timing of the detection of said energy beams relative to the reception of said reference signals; measuring the elevation of the grading implement according to the height at which said first energy beam strikes said energy beam receiver; determining the desired elevation of the grading implement according to the steps of finding two elevation-defining line segments near to and surrounding the position of the grading implement, finding the elevations of two points on the line segments, wherein said two points define a line through the position of the grading implement and wherein the elevation of a point located on a line segment is found by interpolating between the elevations of the two end points of that line segment, and interpolating between the elevations of said two points to determine the desired elevation of the position of the grading implement; and determining an elevation error of the grading implement according to the difference between the measured elevation and the desired elevation thereof.

Claim 104

A method for sensing the position and elevation of a grading implement of an earth-moving vehicle and for determining an elevation error of the grading implement relative to a desired elevation, wherein the desired elevation of the grading implement at a particular position is the elevation that would allow the grading implement to produce a desired graded surface at that position, and wherein the elevation error is the difference between the actual and desired elevations of the grading implement, said method comprising the steps of: selecting a plurality of elevation-defining line segments along which the desired contour of the land has a constant slope, wherein each line segment has end points at which the position and desired elevation is known; projecting a first energy beam that sweeps in a datum plane across the area to be graded, wherein all elevations are defined relative to said datum plane; generating a first reference signal when said first energy beam is aligned with a first reference line; projecting a second energy beam that sweeps in a plane across the area to be graded, wherein said first and second energy beams are transmitted from transmitters that are positioned apart at known positions relative to said elevation-defining line segments; generating a second reference signal when said second energy beam is aligned with a second reference line; detecting said first and second energy beams by an energy beam receiver that is coupled to a grading implement of an earth-moving vehicle for movement therewith; receiving said first and second reference signals by a reference signal receiver that is coupled to the earth-moving vehicle for movement therewith; determining the position of the grading implement relative to said transmitters according to the timing of the detection of said energy beams relative to the reception of said reference signals; measuring the elevation of the grading implement according to the height at which said first energy beam strikes said energy beam receiver; determining the desired elevation of the grading implement according to the steps of finding two elevation-defining line segments near to and surrounding the position of the grading implement, finding the elevations of two points on the line segments, wherein said two points define a line through the position of the grading implement and wherein the elevation of a point located on a line segment is found by interpolating between the elevations of the two end points of that line segment, and interpolating between the elevations of said two points to determine the desired elevation of the position of the grading implement; and determining an elevation error of the grading implement according to the difference between the measured elevation and the desired elevation thereof.