Techniques for compensating for errors in an optical air data system
AssigneeHoneywell International Inc.
InventorsZbynek Drasal, Thomas Dobbins, Matthew Wiebold
Life of this patent
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Abstract
Techniques are provided for symmetrically positioning lines of sights of a pair of emitting optics and receiving optics on and/or in a surface of a body of a vehicle. Such symmetrical positioning aides in determining whether at least one measured free stream air velocity is in error. Upon determining that at least one measured free stream air velocity is in error, then a velocity correction factor for each measured free stream air velocity determined to be in error is determined and/or an alert about each error is transmitted to an operator of the vehicle and/or to at least one other system.
Claims20
An apparatus configured to be mounted on and/or in a body of a vehicle, wherein the body is defined by a first Cartesian coordinate system including a first z axis parallel to a longitudinal axis of the body pointing from a rear to a front of the body, a first x axis laterally bisecting a top and a bottom of the body, and a first y axis bisecting a left hand side and a right hand side of the body, a LIDAR (light detection and ranging) system includes the apparatus, a laser configured to emit an optical signal to each emitting optics, an optical and electrical processing circuit configured to receive the optical signal and each return optical signal and to generate at least one air data parameter, the apparatus comprising:
- a first surface, and N pairs of emitting optics and receiving optics in and/or on the first surface, wherein the first surface is defined by a second x axis and a second y axis of a second Cartesian coordinate system that also includes a second z axis projecting orthogonally from the first surface, wherein N is a first integer greater than one, wherein a emitting optics, of a unique pair, is configured to transmit an optical beam, and wherein the receiving optics, of the unique pair, is configured to receive a return optical signal derived by reflection and/or scattering, from atmosphere, of the optical beam, wherein either (a) each optical beam is transmitted along a unique line of sight (LOS) or (b) each return optical signal is received along the unique LOS;
- wherein (i) the first and the second y axes are separated by a first signed angle that is a second integer multiplied by ninety degrees, and (ii) the first and the second z axes are separated by a second signed angle that is a third integer multiplied by ninety degrees;
- wherein each projection of a LOS on the first surface is separated from each projection of an adjacent LOS on the first surface by a separation angle, wherein the separation angle is substantially equal to three hundred and sixty degrees divided by N so that an accuracy of each air data parameter, generated by the LIDAR system, is within a range specified for the LIDAR system;
- and
- wherein a projection of one LOS on the first surface is offset from the second x axis by an initial separation angle of substantially a fourth integer multiplied by forty five degrees so that the accuracy of each air data parameter, generated by the LIDAR system, is within the range specified for the LIDAR system.
A method for determining if one or more velocities measured utilizing apparatus are in error, the method comprising:
- emitting a transmitted optical beam from each emitter optics of an apparatus, in and/or on a first surface, along a unique line of sight, wherein the apparatus is configured to be mounted on and/or in a body of a vehicle, wherein the body is defined by a first Cartesian coordinate system including a first z axis parallel to a longitudinal axis of the body pointing from a rear to a front of the body, a first x axis laterally bisecting a top and a bottom of the body, and a first y axis bisecting a left hand side and a right hand side of the body, a LIDAR (light detection and ranging) system includes the apparatus, a laser configured to emit an optical signal to each emitting optics, an optical processing system configured to receive the optical signal and each return optical signal and to generate at least one air data parameter, wherein the apparatus comprises:
- a first surface, and N pairs of emitting optics and receiving optics in and/or on the first surface, wherein the first surface is defined by a second x axis and a second y axis of a second Cartesian coordinate system that also includes a second z axis projecting orthogonally from the first surface, wherein N is a first integer greater than one, wherein emitting optics, of a unique pair, is configured to transmit an optical beam, and wherein the receiving optics, of the unique pair, is configured to receive a return optical signal derived by reflection and/or scattering, from atmosphere, of the optical beam, wherein either (a) each optical beam is transmitted along a unique line of sight (LOS) or (b) each return optical signal is received along the unique LOS;
- wherein (i) the first and the second y axes are separated by a first signed angle that is a second integer multiplied by ninety degrees, and (ii) the first and the second z axes are separated by a second signed angle that is a third integer multiplied by ninety degrees;
- wherein each projection of a LOS on the first surface is separated from each projection of an adjacent LOS on the first surface by a separation angle, wherein the separation angle is substantially equal to three hundred and sixty degrees divided by N so that an accuracy of each air data parameter, generated by the LIDAR system, is within a range specified for the LIDAR system;
- and wherein a projection of one LOS on the first surface is offset from the second x axis by an initial separation angle of substantially a fourth integer multiplied by forty five degrees so that the accuracy of each air data parameter, generated by the LIDAR system, is within the range specified for the LIDAR system;
- emitting a transmitted optical beam from each emitter optics along a unique line of sight;
- receiving each received optical signal, derived from a unique transmitted optical beam, at a unique receiving optics in and/or on the first surface;
- determining a measured free stream air velocity for each line of sight;
- determining, using each measured free stream air velocity, whether a magnitude of at least one measured free stream air velocity is in error;
- and
- determining that at least one measured free stream air velocity is in error, then determining a velocity correction factor for each measured free stream air velocity determined to be in error and/or transmitting an alert about each error to an operator of the vehicle and/or to at least one other system.
An optical head configured to be mounted on and/or in a body of a vehicle, wherein the body is defined by a first Cartesian coordinate system including a first z axis parallel to a longitudinal axis of the body pointing from a rear to a front of the body, a first x axis laterally bisecting a top and a bottom of the body, and a first y axis bisecting a left hand side and a right hand side of the body, a LIDAR (light detection and ranging) system includes the optical head, a laser configured to emit an optical signal to each emitting optics, an optical processing system configured to receive the optical signal and each return optical signal and to generate at least one air data parameter, the optical head comprising:
- a first surface, and N pairs of emitting optics and receiving optics in and/or on the first surface, wherein the first surface is defined by a second x axis and a second y axis of a second Cartesian coordinate system that also includes a second z axis projecting orthogonally from the first surface, wherein N is a first integer greater than one, wherein emitting optics, of a unique pair, is configured to transmit an optical beam, and wherein the receiving optics, of the unique pair, is configured to receive a return optical signal derived by reflection and/or scattering, from atmosphere, of the optical beam, wherein either (a) each optical beam is transmitted along a unique line of sight (LOS) or (b) each return optical signal is received along the unique LOS;
- wherein (i) the first and the second y axes are separated by a first signed angle that is a second integer multiplied by ninety degrees, and (ii) the first and the second z axes are separated by a second signed angle that is a third integer multiplied by ninety degrees;
- wherein each projection of a LOS on the first surface is separated from each projection of an adjacent LOS on the first surface by a separation angle, wherein the separation angle is substantially equal to three hundred and sixty degrees divided by N so that an accuracy of each air data parameter, generated by the LIDAR system, is within a range specified for the LIDAR system;
- wherein a projection of one LOS on the first surface is offset from the second x axis by an initial separation angle of substantially a fourth integer multiplied by forty five degrees so that the accuracy of each air data parameter, generated by the LIDAR system, is within the range specified for the LIDAR system;
- wherein N is less than five;
- and
- wherein each LOS has an elevation angle, with respect to the first surface, of (a) substantially forty five degrees so that the accuracy of each air data parameter, generated by the LIDAR system, is within the range specified for the LIDAR system and when N equals four, (b) substantially 35.2 degrees so that the accuracy of each air data parameter, generated by the LIDAR system, is within the range specified for the LIDAR system and when N equals three, and (c) substantially forty-five degrees so that the accuracy of each air data parameter, generated by then LIDAR system, is within the range specified for the LIDAR system and when N equals two.
Dependencies are inferred from the claim text.