A method and device for calibrating a sensor boresight line and a three-axis gyro axis system

Abstract

The present application relates to airborne photoelectric equipment technical field, the present application provides a kind of sensor visual axis sight line and three-axis gyro axis system calibration method and device, device includes: three-axis turntable, sensor group, three-axis gyro group, collimator and total station, three-axis turntable is equipped with outer ring, middle ring and inner ring, sensor group is installed on the inner ring base panel of three-axis turntable, wherein, sensor group is equipped with imaging channel;Three-axis gyro group is located on sensor group;Collimator is located in the imaging channel front of sensor group, total station is located between three-axis turntable and collimator.The present application can be according to the result of calibration correction three-axis gyro group output rate data, to improve the measurement accuracy of sensor visual axis sight line space rate, to improve airborne photoelectric equipment stability precision, can be widely applied to various high-precision stable platform, wide application range, with certain application and popularization value.

Description

Technical Field

[0001] This invention relates to the field of airborne optoelectronic equipment technology, and is applicable to various high-precision line-of-sight stabilization platforms. In particular, it relates to a method and apparatus for calibrating the sensor line-of-sight aiming line and the three-axis gyroscope axis system. Background Technology

[0002] As users' demands for long-range imaging and detection continue to increase, the spatial resolution of imaging sensors in airborne optoelectronic equipment is constantly improving, leading to increasingly higher requirements for the stabilization accuracy of servo stabilization platforms, sometimes even reaching the micro-arc level. As a crucial data acquisition unit within airborne optoelectronic equipment, the gyroscope is a vital data source for the servo stabilization platform to achieve closed-loop control and isolate external disturbances; its accuracy directly impacts the final accuracy of the servo system.

[0003] Traditional airborne optoelectronic equipment (e.g., airborne optoelectronic pods) often uses azimuth gyroscopes and pitch gyroscopes to sense the azimuth and pitch axis rotation rates, respectively, and uses these as input sources for servo stabilization. This approach relies entirely on structural fabrication and assembly to ensure the orthogonality between the gyroscopes, without considering whether the imaging channel sensor's line of sight is orthogonal to the gyroscope axis. This results in a "circular" phenomenon where the center of the image rotates around a certain point in the user's view. The root cause of this problem is that the rate data acquired by the gyroscope cannot accurately represent the rotation rate of the imaging channel sensor's line of sight. Since the gyroscope output data typically contains its own random walk, zero-bias error, and includes the Earth's rotation component, and the sensor's line of sight cannot be directly measured, calibrating the spatial relative relationship between the two and correcting the gyroscope's output rate data to improve the stabilization accuracy of airborne optoelectronic equipment remains a challenge that has not yet been overcome in current technology.

[0004] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0005] In view of the prior art, the present invention provides a new solution for calibrating the spatial relative relationship between the sensor's line of sight and the three-axis gyroscope axis system, correcting the rate data of the gyroscope output, and thus improving the stability accuracy of airborne optoelectronic equipment.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for calibrating the sight line of a sensor with the axis of a three-axis gyroscope, comprising:

[0008] S1, sequentially zero out the outer ring, middle ring and inner ring shaft systems of the three-axis turntable;

[0009] S2, install the sensor group on the inner ring base panel of the three-axis turntable, and place the collimator in front of the sensor group to ensure that the crosshairs of the collimator can be seen after the sensors of each imaging channel are powered on.

[0010] S3. Place the total station between the collimator and the three-axis turntable, and use the total station to level the collimator to ensure that the crosshairs of the collimator coincide with the central crosshairs of the total station.

[0011] S4, by adjusting the zero position of the outer ring of the three-axis turntable and adjusting the gap between the sensor group and the inner ring base panel, the aiming line of the sensor's line of sight is made parallel or orthogonal to the outer ring, middle ring and inner ring axis system of the three-axis turntable.

[0012] S5, rotate the outer ring, middle ring and inner ring of the three-axis turntable in sequence, and simultaneously record and calculate the rate data output by the three-axis gyroscope group. Process the rate data output by the three-axis gyroscope group to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor line of sight.

[0013] S6 uses the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight to correct the rate data output by the three-axis gyroscope group.

[0014] Preferably, in S3, the total station is equipped with a telescope and a level bubble, and the leveling of the collimator using the total station includes:

[0015] S31, use a level bubble to level the total station;

[0016] S32, use the telescope to aim at the collimator crosshair, rotate the collimator crosshair so that the telescope aiming line crosshair coincides with the collimator crosshair;

[0017] S33, rotate the telescope's elevation and azimuth angles by 180° respectively, and observe again whether the telescope's aiming crosshairs coincide with the collimator's crosshairs.

[0018] S34. Based on the alignment of the telescope's aiming crosshairs with the collimator's crosshairs, if they do not align, adopt the corresponding adjustment strategy until the telescope's aiming crosshairs and the collimator's crosshairs align.

[0019] Preferably, in S34, if the elements do not overlap, a corresponding adjustment strategy is adopted, including:

[0020] S341, estimate the deviation between the crosshairs of the telescope's aiming line and the crosshairs of the collimator;

[0021] S342, based on the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator, adjust the height of the collimator support column so that the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator is approximately halved.

[0022] S343 sets the current azimuth angle of the total station to zero, and continues to repeat S33 and S34.

[0023] Preferably, in S5, the rotation of the outer ring, middle ring and inner ring of the three-axis turntable in sequence includes: rotating by a preset angle in the clockwise direction and rotating by the same preset angle in the counterclockwise direction.

[0024] Preferably, in S5, the sequential rotation of the outer ring, middle ring, and inner ring of the three-axis turntable, and the simultaneous recording and calculation of the rate data output by the three-axis gyroscope group, includes:

[0025] S51, rotate the outer ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head1, pitch1, roll1], keep it still for 2 minutes; rotate the outer ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head2, pitch2, roll2], keep it still for 2 minutes;

[0026] S52, rotate the middle ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head3, pitch3, roll3], keep it still for 2 minutes; rotate the middle ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head4, pitch4, roll4], keep it still for 2 minutes;

[0027] S53, rotate the inner ring 3600 degrees clockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head5, pitch5, roll5], keep it still for 2 minutes; rotate the inner ring 3600 degrees counterclockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head6, pitch6, roll6], keep it still for 2 minutes;

[0028] Here, head, pitch, and roll represent the angular integrals with respect to the X, Y, and Z axes, respectively.

[0029] Preferably, in S5, the processing of the rate data output by the three-axis gyroscope group specifically involves:

[0030] By subtracting the clockwise rotation data from the counterclockwise rotation data, random noise and the Earth's rotation component in the gyroscope data are eliminated.

[0031] Preferably, in S5, the processing of the rate data output by the three-axis gyroscope group to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight is specifically as follows:

[0032]

[0033] Where M represents the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight.

[0034] Preferably, in S6, the step of correcting the rate data output by the three-axis gyroscope group using the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight specifically involves:

[0035] (head var pitch var Yoll var ) = (head org pitch org ,roll org )×M

[0036] Where var represents the correction value and org represents the initial value.

[0037] In a second aspect, the present invention provides a device for calibrating the sensor line of sight and the three-axis gyroscope axis system, using the method for calibrating the sensor line of sight and the three-axis gyroscope axis system described in the first aspect, comprising:

[0038] The system consists of a three-axis turntable, a sensor group, a three-axis gyroscope group, a collimator, and a total station. The three-axis turntable has an outer ring, a middle ring, and an inner ring. The sensor group is mounted on the inner ring base panel of the three-axis turntable, and the sensor group has an imaging channel. The three-axis gyroscope group is located on the sensor group. The collimator is located directly in front of the imaging channel of the sensor group. The total station is located between the three-axis turntable and the collimator.

[0039] Preferably, the total station is equipped with a telescope and a level bubble.

[0040] In view of the shortcomings of the prior art, the beneficial effects that the present invention can achieve are as follows:

[0041] This invention can correct the rate data output by the three-axis gyroscope group based on the calibration results, thereby improving the measurement accuracy of the spatial rate of the sensor's line of sight and thus improving the stability accuracy of airborne optoelectronic equipment. It can be widely used in various high-precision stabilization platforms, has a wide range of applications, and has certain application and promotion value. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0043] Figure 1This is a schematic flowchart of a method for calibrating the sensor's line of sight and the three-axis gyroscope axis system according to an embodiment of the present invention;

[0044] Figure 2 This is a schematic flowchart of another method for calibrating the sensor's line of sight and the three-axis gyroscope axis system provided in an embodiment of the present invention;

[0045] Figure 3 This is a schematic flowchart of another method for calibrating the sensor line of sight and the three-axis gyroscope axis system provided in an embodiment of the present invention;

[0046] Figure 4 This is a partial structural schematic diagram of a device for calibrating the sensor's line of sight and the three-axis gyroscope axis system according to an embodiment of the present invention;

[0047] In the accompanying drawings, the same reference numerals are used to denote the same parts or structures, wherein:

[0048] 1-Sensor group, 2-Outer ring axis system of three-axis turntable, 3-Middle ring axis system of three-axis turntable, 4-Inner ring axis system of three-axis turntable, 5, 6-Imaging channels of sensor group, 7-Three-axis gyroscope group. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] In the description of this invention, the terms "inner", "outer", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0051] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] Example 1:

[0053] This embodiment 1 describes a method for calibrating the sensor's line of sight and the three-axis gyroscope's axis system, such as... Figure 1 As shown, it includes:

[0054] S1, sequentially zero out the outer ring, middle ring and inner ring shaft systems of the three-axis turntable.

[0055] In this step, to ensure the stability and reliability of the subsequent series of steps, it is necessary to reset the outer ring, middle ring and inner ring shaft systems of the three-axis turntable to zero respectively.

[0056] S2. Install the sensor group on the inner ring base panel of the three-axis turntable. At the same time, place the collimator in front of the sensor group to ensure that the crosshairs of the collimator can be seen after the sensors of each imaging channel are powered on.

[0057] In this step, the overall assembly of the sensor group can be completed in advance. After powering on, the test can be performed to confirm that each imaging channel in the sensor group can produce clear images and that the data acquisition of the three-axis gyroscope group is normal.

[0058] S3. Place the total station between the collimator and the three-axis turntable, and use the total station to level the collimator, ensuring that the crosshairs of the collimator coincide with the central crosshairs of the total station.

[0059] As one implementation method, in S3, the total station is equipped with a telescope and a level bubble. The collimator is leveled using the total station, as shown below. Figure 2 As shown, it includes:

[0060] S31, use a level bubble to level the total station.

[0061] S32, use the telescope to aim at the collimator crosshairs, rotate the collimator crosshairs so that the telescope aiming line crosshairs coincide with the collimator crosshairs.

[0062] S33, rotate the telescope's elevation and azimuth angles by 180° respectively, and observe again whether the telescope's aiming crosshairs coincide with the collimator crosshairs.

[0063] S34. Based on the alignment of the telescope's aiming crosshairs with the collimator's crosshairs, if they do not align, adopt the corresponding adjustment strategy until the telescope's aiming crosshairs and the collimator's crosshairs align.

[0064] As one implementation method, in S34, if the statements do not overlap, a corresponding adjustment strategy is adopted, such as... Figure 3 As shown, it includes:

[0065] S341, estimate the deviation between the crosshairs of the telescope's aiming line and the crosshairs of the collimator.

[0066] S342, based on the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator, adjust the height of the collimator support column so that the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator is approximately halved.

[0067] In S341 and S342, taking the X and Y axis directions as examples, in the X and Y axis directions, assuming that the estimated deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator is (x, y), by adjusting the height of the collimator support column, the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator is made to be (x / 2, y / 2).

[0068] S343 sets the current azimuth angle of the total station to zero, and continues to repeat S33 and S34.

[0069] Through the cyclic adjustments in S341-S343 above, until the crosshairs of the telescope aiming line coincide with the crosshairs of the collimator, at which point the optical axis of the collimator is also horizontal.

[0070] S4, by adjusting the zero position of the outer ring of the three-axis turntable and adjusting the gap between the sensor group and the inner ring base panel, the aiming line of the sensor's line of sight is made parallel or orthogonal to the outer ring, middle ring and inner ring axis system of the three-axis turntable.

[0071] The ultimate goal of this step is to make the sensor's line of sight completely coincide with the crosshairs of the collimator.

[0072] S5, rotate the outer ring, middle ring and inner ring of the three-axis turntable in sequence, and simultaneously record and calculate the rate data output by the three-axis gyroscope group. Process the rate data output by the three-axis gyroscope group to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor line of sight.

[0073] In S5, the outer ring, middle ring and inner ring of the three-axis turntable are rotated in sequence, and the rotation methods include: rotating by a preset angle in the clockwise direction and rotating by the same preset angle in the counterclockwise direction.

[0074] In actual implementation, the sequential rotation of the outer ring, middle ring, and inner ring of the three-axis turntable, and the simultaneous recording and calculation of the rate data output by the three-axis gyroscope group, includes:

[0075] S51: Rotate the outer ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head1, pitch1, roll1], and keep it still for 2 minutes; rotate the outer ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head2, pitch2, roll2], and keep it still for 2 minutes.

[0076] S52, rotate the middle ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head3, pitch3, roll3], and keep it still for 2 minutes; rotate the middle ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head4, pitch4, roll4], and keep it still for 2 minutes.

[0077] S53, rotate the inner ring 3600 degrees clockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head5, pitch5, roll5], keep it still for 2 minutes; rotate the inner ring 3600 degrees counterclockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head6, pitch6, roll6], keep it still for 2 minutes.

[0078] Here, head, pitch, and roll represent the angular integrals with respect to the X, Y, and Z axes, respectively.

[0079] In S5, the processing of the rate data output by the three-axis gyroscope group specifically involves: subtracting the clockwise rotation data from the counterclockwise rotation data to eliminate random noise and the Earth's rotation component in the gyroscope data; further, the processing of the rate data output by the three-axis gyroscope group to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight is specifically as follows:

[0080]

[0081] Where M represents the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight.

[0082] S6 uses the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight to correct the rate data output by the three-axis gyroscope group.

[0083] In S6, the step of correcting the rate data output by the three-axis gyroscope group using the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight is specifically as follows:

[0084] (head var pitch var ,roll var ) = (head org pitch org ,roll org )×M

[0085] Where var represents the correction value and org represents the initial value.

[0086] By applying the above formula, the corrected speed data of the three-axis gyroscope group output can be obtained.

[0087] Example 2:

[0088] Based on the same overall technical concept as Embodiment 1, Embodiment 2 provides a device for calibrating the sensor's line of sight and the three-axis gyroscope axis system, using the method for calibrating the sensor's line of sight and the three-axis gyroscope axis system described in Embodiment 1, such as... Figure 4 As shown, it includes:

[0089] The system consists of a three-axis turntable, sensor group 1, three-axis gyroscope group 7, collimator, and total station. The three-axis turntable has an outer ring 2, a middle ring 3, and an inner ring 4. Sensor group 1 is mounted on the inner ring base panel of the three-axis turntable. Sensor group 1 has imaging channels 5 and 6. Three-axis gyroscope group 7 is located on sensor group 1. Collimator is located directly in front of imaging channels 5 and 6 of sensor group 1. The total station is located between the three-axis turntable and the collimator.

[0090] The total station is equipped with a telescope and a level bubble. The telescope is used to level the collimator, and the level bubble is used to level the total station.

[0091] In summary, this invention provides a method and apparatus for calibrating the sensor's line of sight and the three-axis gyroscope system. The calibration results can be used to correct the rate data output by the three-axis gyroscope assembly, thereby improving the measurement accuracy of the spatial rate of the sensor's line of sight and thus enhancing the stability accuracy of airborne optoelectronic equipment. This method can be widely applied to various high-precision stabilization platforms, has a broad application range, and possesses significant application and promotion value.

[0092] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for calibrating the sight line of a sensor with the axis of a three-axis gyroscope, characterized in that, include: S1, sequentially zero out the outer ring, middle ring and inner ring shaft systems of the three-axis turntable; S2, install the sensor group on the inner ring base panel of the three-axis turntable, and place the collimator in front of the sensor group to ensure that the crosshairs of the collimator can be seen after the sensors of each imaging channel are powered on. S3. Place the total station between the collimator and the three-axis turntable, and use the total station to level the collimator to ensure that the crosshairs of the collimator coincide with the central crosshairs of the total station. S4, by adjusting the zero position of the outer ring of the three-axis turntable and adjusting the gap between the sensor group and the inner ring base panel, the aiming line of the sensor's line of sight is made parallel or orthogonal to the outer ring, middle ring and inner ring axis system of the three-axis turntable. S5, rotate the outer ring, middle ring and inner ring of the three-axis turntable in sequence, and simultaneously record and calculate the rate data output by the three-axis gyroscope group. Process the rate data output by the three-axis gyroscope group to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor line of sight. S6, the rate data output by the three-axis gyroscope group is corrected by the rotation transformation matrix between the three-axis gyroscope axis system and the sensor line of sight; In S5, the outer ring, middle ring and inner ring of the three-axis turntable are rotated in sequence, and the rotation methods include: rotating by a preset angle in the clockwise direction and rotating by the same preset angle in the counterclockwise direction.

2. The method for calibrating the sensor's line of sight and the three-axis gyroscope axis system according to claim 1, characterized in that, In S3, the total station is equipped with a telescope and a level bubble. The leveling of the collimator using the total station includes: S31, use a level bubble to level the total station; S32, use the telescope to aim at the collimator crosshair, rotate the collimator crosshair so that the telescope aiming line crosshair coincides with the collimator crosshair; S33, rotate the telescope's elevation and azimuth angles by 180° respectively, and observe again whether the telescope's aiming crosshairs coincide with the collimator's crosshairs. S34. Based on the alignment of the telescope's aiming crosshairs with the collimator's crosshairs, if they do not align, adopt the corresponding adjustment strategy until the telescope's aiming crosshairs and the collimator's crosshairs align.

3. The method for calibrating the sensor's line of sight and the three-axis gyroscope axis system according to claim 2, characterized in that, In S34, if the statements do not overlap, a corresponding adjustment strategy is adopted, including: S341, estimate the deviation between the crosshairs of the telescope's aiming line and the crosshairs of the collimator; S342, based on the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator, adjust the height of the collimator support column so that the deviation between the crosshairs of the telescope aiming line and the crosshairs of the collimator is halved. S343 sets the current azimuth angle of the total station to zero, and continues to repeat S33 and S34.

4. The method for calibrating the sensor's line of sight and the three-axis gyroscope axis system according to claim 1, characterized in that, In S5, the sequential rotation of the outer ring, middle ring, and inner ring of the three-axis turntable, and the simultaneous recording and calculation of the rate data output by the three-axis gyroscope group, includes: S51, rotate the outer ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head1, pitch1, roll1], keep it still for 2 minutes; rotate the outer ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head2, pitch2, roll2], keep it still for 2 minutes; S52, rotate the middle ring clockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head3, pitch3, roll3], keep it still for 2 minutes; rotate the middle ring counterclockwise 3600 degrees, record the gyroscope data for this segment, and integrate it according to the period to obtain [head4, pitch4, roll4], keep it still for 2 minutes; S53, rotate the inner ring 3600 degrees clockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head5, pitch5, roll5], keep it still for 2 minutes; rotate the inner ring 3600 degrees counterclockwise, record the gyroscope data for this segment, and integrate it according to the period to obtain [head6, pitch6, roll6], keep it still for 2 minutes; Here, head, pitch, and roll represent the angular integrals with respect to the X, Y, and Z axes, respectively.

5. The method for calibrating the sensor line of sight and the three-axis gyroscope axis system according to claim 4, characterized in that, In S5, the processing of the rate data output by the three-axis gyroscope group specifically involves: By subtracting the clockwise rotation data from the counterclockwise rotation data, random noise and the Earth's rotation component in the gyroscope data are eliminated.

6. The method for calibrating the sensor line of sight and the three-axis gyroscope axis system according to claim 5, characterized in that, In S5, the rate data output by the three-axis gyroscope group is processed to obtain the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight, specifically as follows: Where M represents the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight.

7. The method for calibrating the sensor line of sight and the three-axis gyroscope axis according to claim 6, characterized in that, In S6, the step of correcting the rate data output by the three-axis gyroscope group using the rotation transformation matrix between the three-axis gyroscope axis system and the sensor's line of sight is specifically as follows: Where var represents the correction value and org represents the initial value.

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