CN101832737B - HUD (Heads-Up Display) digitized bore-sighting method applied to plane general assembly - Google Patents

Abstract

The invention discloses an HUD (Heads-Up Display) digitized boresight method applied to plane general assembly, comprising the following steps of: (1) leveling a plane, arranging a laser tracker on a lower station, unifying a measuring coordinate system of the laser tracker with an assembly coordinate system of the lower station and centering a water bubble on an HUD boresight device; (2) measuring a No. 2 point and a No. 12 point by utilizing the tracker and constructing a symmetric axis of the plane in a computer; (3) moving the tracker to an upper station and unifying a measuring coordinate system of the tracker with an assembly coordinate system of the upper station; (4) finishing the measurement of a target on the boresight device; (5) calculating and displaying the deviations of the boresight device relative to the construction plane and the symmetric axis of the plane through patterns and finishing HUD boresight if satisfying the requirement or else continuing the HUD boresight; and (6) manually adjusting the mounting position of the boresight device according to the prompts of the computer and repeating the steps (4) and (5) until satisfying the requirement. The invention can effectively improve the boresight precision and the efficiency, lessen the reliance of boresight operation on the size of a field space, and improve the automated and integrated level of plane general assembly.

Description

Head-up display digital target calibration method applied to airplane general assembly

Technical Field

The invention relates to a boresight method, in particular to a head-up display digital boresight method applied to airplane general assembly.

Background

The head-up display is a set of photoelectric display equipment with more complete functions than an optical sighting device, and the positioning and mounting precision of the head-up display directly influences the precision of an airplane fire control system. Therefore, the mounting and positioning of the head-up display must be calibrated to ensure the accuracy of the fire control of the aircraft system. China's dominant boresight method still follows the traditional optical boresight means for many years, and degree of automation is low, and the credibility of measured data is poor, and the space occupied by the job site is large, has seriously inhibited the improvement of boresight precision and the improvement of boresight efficiency.

Disclosure of Invention

The invention aims to provide a head-up display digital boresight method applied to general assembly of an airplane, aiming at the defects of the traditional optical boresight technology and the urgent need of improving the automation and integration level of the general assembly of the airplane.

1) Leveling an airplane, placing a laser tracker at a lower station position, unifying a measurement coordinate system of the laser tracker with an assembly coordinate system of the lower station position, and adjusting a bubble on a flat display target correcting device to be centered;

2) measuring 2# and 12# measuring points by using a laser tracker, and constructing a plane symmetry axis in a computer;

3) moving the tracker to the position of the upper station, wherein the measurement coordinate system of the laser tracker is unified with the assembly coordinate system of the upper station;

4) starting a measuring program, and finishing target point measurement on the head-up display target calibration device by adopting a manual measuring mode or an automatic measuring mode;

5) calculating and graphically displaying deviation conditions of the head-up display target correcting device relative to a plane and a symmetrical axis of the airplane structure, namely simulating a real target plate by using a virtual target plate to give an imaged head-up display target correcting result and prompting an adjustment direction. Finishing the head display target calibration if the calculated deviation is within the allowable deviation range, and otherwise, continuing;

6) and (4) manually adjusting the installation position of the level display target correcting device according to the prompt of the computer, and repeating the steps 4) to 5) after the adjustment is finished until the level display target correcting requirement is met.

The head-up display target calibration device comprises a head-up display target calibration template, a target and a bubble, wherein the target and the bubble are arranged on the head-up display target calibration template.

The method is characterized in that 2# and 12# measuring points are measured by using a laser tracker, and the step of constructing the symmetry axis of the airplane in a computer comprises the following steps:

1) measuring 2# and 12# by using laser trackerMeasurement point P_2#，P_12#：

P_2#＝(x_2#，y_2#，z_2#)，P_12#＝(x_12#，y_12#，z_12#)；

2) Will P_2#，P_12#Projecting to XOZ plane to obtain projection point P_2# ^⊥XOZ，P_12# ^⊥XOZ：

${\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_{2\#}^{\&perp;\mathrm{XOZ}}=(x_{2\#},0,z_{2\#}),$ $P_{12\#}^{\&perp;\mathrm{XOZ}}=(x_{12\#},0,z_{12\#});$

3) Then P is_12# ^⊥XOZP_2# ^⊥XOZI.e. determining the aircraft symmetry axis L:

$L\left(t\right)=P_{12\#}^{\&perp;\mathrm{XOZ}}+t\&CenterDot;d$

wherein, $d=\frac{P_{12\#}^{\&perp;\mathrm{<figure-callout\; id="2"\; label="XOZ\; P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">XOZ</figure-callout>}}{P}_{}^{}{}_{2\#}^{\&perp;\mathrm{XOZ}}}{\left|\right|P_{12\#}^{\&perp;\mathrm{<figure-callout\; id="2"\; label="XOZ\; P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">XOZ</figure-callout>}}{P}_{}^{}{}_{2\#}^{\&perp;\mathrm{XOZ}}\left|\right|},$ the direction of the aircraft axis of symmetry L is characterized.

The step of calculating and graphically displaying the deviation of the head-up display boresight device relative to the horizontal plane and the symmetry axis of the airplane structure comprises the following steps of:

1) measuring 4 target points P on the level display target correcting device by using a laser tracker_M1，P_M2，P_M3，P_M4：P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2)，P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4)；

2) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting it to XOY plane to calculate the pitch error theta of the head-up display target correcting device_pitch：

${\mathrm{\&theta;}}_{\mathrm{pitch}}=\arctan \frac{y_{M2}-y_{M1}}{x_{M2}-x_{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">M</figure-callout>}1}};$

3) According to P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4) Projecting it to YOZ plane to calculate the rolling error theta of head-up display target correcting device_roll：

${\mathrm{\&theta;}}_{\mathrm{roll}}=\arctan \frac{y_{M4}-y_{M3}}{z_{M4}-{\mathrm{<figure-callout\; id="3"\; label="z\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">z</figure-callout>}}_M};$

4) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting it to XOZ plane to calculate the azimuth error theta of the plane display target correcting device_azimuth：

${\mathrm{\&theta;}}_{\mathrm{azimuth}}=\arctan \frac{z_{M2}-z_{M1}}{x_{M2}-x_{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">M</figure-callout>}1}};$

5) Calculating the position of an aiming point of the head-up display target correcting device on the simulated target plate:

target point P_M1The projected points on the simulated target plate are,

target point P_M3The projected points on the simulated target plate are,

target point P_M4The projected points on the simulated target plate are,

-aiming point P_MAThe projected points on the simulated target plate are,

——P_MA ^⊥relative P_M1 ^⊥The amount of the offset of (a) is,

wherein,

d-target point P_M1Distance to actual target plate;

space of the head-up display boresight device relative to the axis of symmetry of the aircraftThe deflection angle, which is calculated as follows:

firstly, calculating the course direction of the head-up display target correcting device

$d_{\mathrm{CRT}}=\frac{P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M}{\left|\right|P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M\left|\right|}$

Then the process of the first step is carried out,

aiming point P_MA ^⊥The calculation process of (2) is as follows:

from P_M1P_M2Determining a straight line L_C：

L_C(t)＝P_M1+td_C

Wherein, $d_C=d_{\mathrm{CRT}}=\frac{P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M}{\left|\right|P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M\left|\right|},$ characterization line L_CDirection of (1)

Then, P_MA＝L_C(t′)＝P_M1+t′d_C

Wherein,

according to $P_{\mathrm{MS}}^{\&perp;}=(0,y_{\mathrm{MA}},z_{\mathrm{MA}}),$ That is to obtain P_MA ^⊥。

The invention has the advantages that: 1) compared with the traditional optical target calibration method, the digital target calibration measuring system can effectively improve the target calibration precision, greatly improve the target calibration efficiency and remarkably reduce the dependence of the target calibration process on the size of the working site space; 2) further improves the automation and integration level of the aircraft assembly.

Drawings

FIG. 1(a) is a schematic diagram of a flat display proof template and an original telescope according to an embodiment of the present invention;

FIG. 1(b) is a schematic diagram of a flat display proof template and a flat display proof apparatus according to an embodiment of the present invention;

FIG. 1(c) is a top view of a flat display target calibration device according to an embodiment of the present invention;

FIG. 2(a) is a side view of an applause boresight measurement arrangement according to an embodiment of the present invention;

FIG. 2(b) is a front view of a head-up boresight measurement layout according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a calculation of a head-up calibration target according to an embodiment of the present invention;

FIG. 4 is a flowchart of a software system for flat display boresight according to an embodiment of the present invention.

In the figure: the device comprises a head-up display boresight template 1, an original telescope 2, a target 3, a bubble 4, a certain type airplane 5, a laser tracker upper station 6, a head-up display boresight device (provided with the target and the bubble) 7, an upper station and a lower station unified coordinate system shared measuring point 8, a laser tracker lower station 9 and 2# and 12# measuring points 10 for determining the symmetry axis of the airplane.

Detailed Description

The invention combines the advanced laser tracker measuring technology and the auxiliary boresight device, and realizes the process of boresight of a plane display of a certain type by using a digital measuring means. The implementation process mainly comprises two steps: firstly, reasonably selecting a measuring point reflecting the pose of a head-up display target correcting template (in practical application, the head-up display is detached, and the head-up display target correcting template replaces the head-up display to correct the target), and acquiring the practical installation pose by a high-precision laser tracking measurement technology; and then, calculating the deviation of the actual installation pose relative to the theoretical target pose, simultaneously displaying the deviation result on a computer in an intuitive imaging manner, and automatically providing an effective and feasible scheme for adjusting the pose of the head-up display boresight template once the pose deviation exceeds a given threshold value. The invention organically integrates a plurality of technologies such as mechanical design, laser measurement, data processing, computer imaging, network communication and the like, and compared with the traditional optical target calibration method, the digital target calibration measurement system can effectively improve the target calibration precision and greatly improve the target calibration efficiency. .

The digital boresight system for the flat display is described in the following five aspects of a device for the flat display boresight and the working principle thereof, a measuring method, measurement precision analysis, a deviation calculation method and software module design.

The technical requirements of the head-up display target calibration of a certain type of airplane are as follows: and the pitching, rolling and azimuth directions of the head-up display target calibration device are correctly calibrated.

1. Head-up display target correcting device and working principle thereof

The level display target calibration device is shown in fig. 1 and comprises a level display target calibration template, 4 targets for laser tracking measurement and blisters. The technical parameters and performance indexes are as follows:

1) the target correcting template can replace a head up display to be arranged on the head up display mounting seat, the working plane and the working axis of the template can correctly reflect the position and the direction of the head up display, and the deviation does not exceed 0.04 DEG;

2) the boresight precision of the head display boresight system can meet the design requirement of the head display boresight of the airplane;

3) the target correcting device is simple to install and convenient to operate.

The working principle is as follows:

adjusting the bubble to be centered to ensure that the head-up display target calibration device is correctly calibrated in the roll direction, and calculating the roll error of the head-up display target calibration device by measuring 2 target points on the installation bases at two sides and projecting the measured value to the YOZ plane; by measuring 2 target points on the central mounting base and projecting the measured values to the XOZ plane and the XOY plane respectively, the azimuth error and the pitch error of the head-up display target calibration device can be calculated.

2. Measurement layout and measurement implementation method

Measurement layout:

the layout of the head-up boresight is shown in FIG. 2. The laser tracker is arranged on the side surface of a certain airplane 5 and is divided into an upper station 6 and a lower station 9, when the laser tracker is positioned at the lower station 9, the laser tracker is responsible for measuring 2# and 12# measuring points 10, and when the laser tracker is positioned at the upper station 6, the laser tracker is responsible for measuring a target 7 on the flat display target correcting device.

In order to unify the measuring coordinate systems of the two stations, 4 fixed common target points 8 which can be measured at the two stations are arranged on the ground.

The arrangement of targets on the head-up display target calibration device is shown in figure 1, 4 targets are arranged, and the connecting line of the centers of the targets is consistent with the center line of the current telescope.

The measurement implementation method comprises the following steps:

1) leveling an airplane, namely adjusting the horizontal direction and the longitudinal direction of the airplane, the method comprises the following steps: two measuring points are symmetrically arranged on left and right wings of an airplane, the height difference of the two points is within 0.5mm to achieve transverse leveling, the two measuring points are arranged along the direction of the airplane body, the height difference of the two points is within 0.5mm to achieve longitudinal leveling, then, a laser tracker is placed at the position of a lower station, a measuring coordinate system of the laser tracker is unified with an assembling coordinate system of the lower station, wherein the measuring coordinate system of the laser tracker refers to a space coordinate system which is automatically established by default after the laser tracker is started, the assembling coordinate system of the lower station refers to a space coordinate system defined by designers according to the layout of the field airplane general assembly, and the method for unifying the two is as follows: the method comprises the steps of obtaining measured values of a plurality of public observation points arranged on the ground by measuring the public observation points, namely space coordinate values of the points under a laser tracker measuring coordinate system, reading nominal values of the public observation points under an assembly coordinate system of a lower station, and applying a classical point matching algorithm to the two values, so that the unification of two coordinate systems can be realized, and the centering of a bubble on a flat display target correcting device can be adjusted;

2) measuring 2# and 12# measuring points by using a laser tracker, and constructing a plane symmetry axis in a computer;

3) moving the tracker to the position of the upper station, unifying a measurement coordinate system of the laser tracker with an assembly coordinate system of the upper station, and unifying the coordinate systems in the same step 1);

4) starting a measuring program, and finishing target point measurement on the head-up display target calibration device by adopting a manual measuring mode or an automatic measuring mode;

5) calculating and graphically displaying deviation conditions of the head-up display target correcting device relative to a plane and a symmetrical axis of the airplane structure, namely simulating a real target plate by using a virtual target plate to give an imaged head-up display target correcting result and prompting an adjustment direction. Finishing the head display target calibration if the calculated deviation is within the allowable deviation range, and otherwise, continuing;

6) and (4) manually adjusting the installation position of the level display target correcting device according to the prompt of the computer, and repeating the steps 4) to 5) after the adjustment is finished until the level display target correcting requirement is met.

3. Measurement accuracy analysis

The precision index of the Leica AT901-LR type laser tracker is as follows: in the full range (360 degrees in the horizontal direction, +/-45 degrees in the vertical direction, and 80m of the maximum measurement range of the measuring head), the uncertainty of single-point measurement is as follows: and the Uxyz is equal to +/-15 mu m +6 mu m/m, wherein the Uxyz is defined as the deviation between the measured three-dimensional coordinate value and the nominal three-dimensional coordinate value of the measured point.

When measuring the target point, the error of the laser tracking measurement system mainly comes from four aspects: 1. the method comprises the following steps of measuring errors a and 2 of the laser tracker, positioning errors b and 3 of a target mounting seat, transfer errors c and 4 of the laser tracker and foundation vibration errors d. Combining with the related error analysis calculation, a is less than or equal to plus or minus 15 mu m plus 120 mu m, b is 0.0127mm, c is 0.05mm, and d is 0.006 mm.

By integrating the errors in the four aspects, in the process of measuring the target point, the total uncertainty of the laser tracking measurement system is as follows:

$\mathrm{\&epsiv;}\&le;\sqrt{a^2+{\mathrm{<figure-callout\; id="2"\; label="b"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">b</figure-callout>}}^2+{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">c</figure-callout>}}^2+{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">d</figure-callout>}}^2}=0.145\mathrm{mm}$

according to the distance L between the target points on the head-up display target correcting device and the distance D between the rear point of the target and the target plate, the flight direction measurement error can be calculated as follows:

D_{ε _ course}＝Dtanθ_{ε _ course}＝21000×tan(0.030°)＝10.88mm

4. Deviation calculation method

FIG. 3 is a schematic diagram of the calculation of the average display boresight, and the basic calculation process is as follows:

1) measuring two measuring points 2# and 12# by using a laser tracker:

P_2#＝(x_2#，y_2#，z_2#)，P_12#＝(x_12#，y_12#，z_12#)；

will P_2#，P_12#Projecting to XOZ plane to obtain projection point P_2# ^⊥XOZ，P_12# ^⊥XOZ：

${\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_{2\#}^{\&perp;\mathrm{XOZ}}=(x_{2\#},0,{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">z</figure-callout>}}_{2\#}),$ $P_{12\#}^{\&perp;\mathrm{XOZ}}=(x_{12\#},0,z_{12\#});$

Then P is_12# ^⊥XOZP_2# ^⊥XOZI.e. determining the aircraft symmetry axis L:

$L\left(t\right)=P_{12\#}^{\&perp;\mathrm{XOZ}}+t\&CenterDot;d$

wherein, $d=\frac{P_{12\#}^{\&perp;\mathrm{<figure-callout\; id="2"\; label="XOZ\; P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">XOZ</figure-callout>}}{P}_{}^{}{}_{2\#}^{\&perp;\mathrm{XOZ}}}{\left|\right|P_{12\#}^{\&perp;\mathrm{<figure-callout\; id="2"\; label="XOZ\; P"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">XOZ</figure-callout>}}{P}_{}^{}{}_{2\#}^{\&perp;\mathrm{XOZ}}\left|\right|},$ the direction of the aircraft axis of symmetry L is characterized.

2) Measuring 4 target points P with a laser tracker_M1，P_M2，P_M3，P_M4：

P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2)，P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4)；

3) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting it to XOY plane to calculate the pitch error theta of the head-up display target correcting device_pitch：

${\mathrm{\&theta;}}_{\mathrm{pitch}}=\arctan \frac{y_{M2}-y_{M1}}{x_{M2}-{\mathrm{<figure-callout\; id="1"\; label="x\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">x</figure-callout>}}_M};$

4) According to P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4) Projecting it to YOZ plane to calculate the rolling error theta of head-up display target correcting device_roll：

${\mathrm{\&theta;}}_{\mathrm{ro}11}=\arctan \frac{y_{M4}-y_{M3}}{z_{M4}-{\mathrm{<figure-callout\; id="3"\; label="z\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">z</figure-callout>}}_M},$

5) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting it to XOZ plane to calculate the azimuth error theta of the plane display target correcting device_azimuth：

${\mathrm{\&theta;}}_{\mathrm{azimuth}}=\arctan \frac{z_{M2}-z_{M1}}{x_{M2}-{\mathrm{<figure-callout\; id="1"\; label="x\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">x</figure-callout>}}_M};$

6) Calculating the position of the aiming point of the head-up display target correcting device on the simulated target plate, as shown in FIG. 3:

target point P_M1The projected points on the simulated target plate (YOZ plane),

target point P_M3The projected points on the simulated target plate (YOZ plane),

target point P_M4The projected points on the simulated target plate (YOZ plane),

-aiming point P_M4The projected points on the simulated target plate (YOZ plane),

——P_MA ^⊥relative P_M1 ^⊥The amount of the offset of (a) is,

wherein,

d-target point P_M1Distance to the actual target plate (parallel to the YOZ plane when establishing the coordinate system);

the spatial deflection angle of the head-up display target correcting device relative to the symmetry axis of the airplane is calculated as follows:

firstly, calculating the course direction of the head-up display target correcting device

$d_{\mathrm{CRT}}=\frac{P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M}{\left|\right|P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M\left|\right|}$

Then the process of the first step is carried out,

aiming point P_MA ^⊥The calculation process of (2) is as follows:

from P_M1P_M2Determining a straight line L_C：

L_C(t)＝P_M1+td_C

Wherein, $d_C=d_{\mathrm{CRT}}=\frac{P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M}{\left|\right|P_{M1}{\mathrm{<figure-callout\; id="2"\; label="P\; M"\; filenames="HSA00000067933900011.png"\; state="\{\{state\}\}">P</figure-callout>}}_M\left|\right|},$ characterization line L_CDirection of (1)

Then, P_MA＝L_C(t′)＝P_M1+t′d_C

Wherein,

according to $P_{\mathrm{MA}}^{\&perp;}=(0,y_{\mathrm{MA}},z_{\mathrm{MA}}),$ That is to obtain P_MA ^⊥；

5. Software module design

Providing a graphical guide type operation interface according to the process steps and characteristics of the head-up display target calibration, so that an operator can efficiently finish the head-up display target calibration task according to the specified steps according to the graphical guide; the functions of reading the symmetrical axis data of the airplane, automatically or manually measuring target points, calculating the pitching, inclining and course deviation of the head-up display target correcting device, visually displaying the calculation result (simulating a real target plate by a virtual target plate to give an imaged head-up display target correcting result), prompting the adjusting method and the like are sequentially realized. The basic flow is shown in fig. 4.

Claims (2)

1. A head-up display digital boresight method applied to airplane general assembly is characterized by comprising the following steps:

1) leveling an airplane, placing a laser tracker at a lower station position, unifying a measurement coordinate system of the laser tracker with an assembly coordinate system of the lower station position, and adjusting a bubble on a flat display target calibration device to be centered;

2) measuring 2# and 12# measuring points by using a laser tracker, and constructing a plane symmetry axis in a computer;

3) moving the tracker to the position of the upper station, wherein the measurement coordinate system of the laser tracker is unified with the assembly coordinate system of the upper station;

4) starting a measuring program, and finishing target point measurement on the head-up display target calibration device by adopting a manual measuring mode or an automatic measuring mode;

5) calculating and graphically displaying deviation conditions of the head-up display target correcting device relative to a plane and a symmetrical axis of the airplane structure, namely simulating a real target plate by using a virtual target plate to give an imaged head-up display target correcting result, prompting to adjust the direction, finishing head-up display target correcting if the calculated deviation is within an allowable deviation range, and otherwise, continuing;

6) manually adjusting the installation position of the level display target correcting device according to the prompt of a computer, and repeating the steps 4) to 5) after the adjustment is finished until the level display target correcting requirement is met;

the method is characterized in that 2# and 12# measuring points are measured by using a laser tracker, and the step of constructing the symmetry axis of the airplane in a computer comprises the following steps:

1) measuring two measuring points P2 # and 12# by using a laser tracker_2#，P_12#：P_2#＝(x_2#，y_2#，z_2#)，P_12#＝(x_12#，y_12#，z_12#)；

2) Will P_2#，P_12#Projecting to XOZ plane to obtain projection point

3) Then

I.e. determining the aircraft symmetry axis L:

the difference step comprises:

1) measuring 4 target points P on the level display target correcting device by using a laser tracker_M1，P_M2，P_M3，P_M4：P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2)，P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4)；

2) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting the target to XOY plane to calculate the pitch error theta of the head-up display target correcting device_pitch：

3) According to P_M3＝(x_M3，y_M3，z_M3)，P_M4＝(x_M4，y_M4，z_M4) Projecting the image to a YOZ plane to calculate the rolling error theta of the head-up display target correcting device_roll：

4) According to P_M1＝(x_M1，y_M1，z_M1)，P_M2＝(x_M2，y_M2，z_M2) Projecting the image to XOZ plane to calculate azimuth error theta of the head-up display target correcting device_azimuth：

5) Calculating the position of an aiming point of the head-up display target correcting device on the virtual target plate:

target point P_M1The projected point on the virtual target board,

target point P_M3The projected point on the virtual target board,

target point P_M4The projected point on the virtual target board,

-aiming point P_MAThe projected point on the virtual target board,

relative to each otherThe amount of the offset of (a) is,

wherein,

d-target point P_M1Distance to the real target plate;

the spatial deflection angle of the head-up display target correcting device relative to the symmetry axis of the airplane is calculated as follows:

firstly, calculating the course direction of the head-up display target correcting device

Then the process of the first step is carried out,wherein d represents the direction of the aircraft axis of symmetry L

If it is not

Aiming point

The calculation process of (2) is as follows:

from P_M1P_M2Determining a straight line L_C：

L_C(t)＝P_M1+td_C

Wherein,

characterization line L_CDirection of (1)

Then, P_MA＝L_C(t′)＝P_M1+t′d_C

Wherein,

according to

Namely to obtain

2. The digital flat display target calibration method applied to the aircraft general assembly according to claim 1, characterized in that the digital flat display target calibration device comprises a flat display target calibration template (1), a target (3) and a bubble (4), wherein the target (3) and the bubble (4) are arranged on the flat display target calibration template (1).

Images