CN106153074A - A kind of optical calibrating system and method for the dynamic navigation performance of IMU - Google Patents

Abstract

The invention discloses the optical calibrating system and method for the dynamic navigation performance of a kind of IMU.Single laser displacement sensor is utilized to measure displacement, the method that two laser displacement sensors measure angle, measure IMU in real time under vibration table provides the external environment condition of dynamic navigation performance test, displacement and the angle of measuring IMU in real time of three dimensions, and the output valve of the angle that measurement obtained and displacement information and IMU compares, thus realize the purpose that the dynamic navigation performance of IMU is demarcated.The IMU dynamic navigation performance optical calibration method that the present invention proposes realizes non-cpntact measurement, measures IMU output in real time, carries roomy, and stability is high, has the most wide application prospect.

Description

An optical calibration system and method for inertial measurement combined dynamic navigation performance

technical field

The invention relates to an optical calibration system and method for inertial measurement combined dynamic navigation performance, belonging to the field of optical sensing and measurement.

technical background

The inertial measurement unit is the core measurement unit of inertial navigation, and its performance determines the navigation accuracy and attitude control accuracy of the carrier. Whether the inertial measurement combination can accurately reflect the actual motion information of the carrier in a dynamic environment is the key to evaluating the performance of the inertial measurement instrument. In order to accurately evaluate the dynamic navigation accuracy and attitude measurement accuracy of the inertial measurement combination under dynamic conditions during the ground test phase, another independent evaluation method needs to be provided to evaluate the navigation and attitude measurement performance of the inertial measurement combination under dynamic conditions over a period of time. In order to ensure the real-time performance of the evaluation, the independent measurement method must be able to synchronize with the measurement time of the inertial measurement combination, and provide the pitch angle, yaw angle, roll angle and three-dimensional displacement information of the inertial measurement combination relative to the initial position in real time, so as to realize the evaluation of the inertial measurement combination Real-time calibration of dynamic performance.

After research, there is currently no high-precision, reliable measurement equipment that uses non-contact optical methods for inertial measurement combined dynamic information measurement and calibration. The existing calibration methods for angle and displacement are as follows: 1) Use circular grating for angle measurement and line grating for displacement measurement. The advantages are high measurement accuracy, fast response and large dynamic range. The disadvantage is that it cannot be realized. Non-contact measurement, or too far away from the measured object, can not accurately reflect the movement of the measured object; 2) light curtain measurement method: use two orthogonal light curtains for measurement, and the light curtain blocked by the object has a corresponding By detecting the shape of the object, the deformation of the object is measured, and the angle and displacement are detected in real time according to the deformation. Advantages: Two sets of light curtains can simultaneously measure a variety of information to determine the attitude of the sample between the two sets of projections. Disadvantages: low precision, difficult to ensure parallel light, small measurement range, not flexible enough; 3) This method needs to install a reflector on the three mutually orthogonal surfaces of the measured object to achieve specular reflection of the laser , while the PSD realizes the reception of the reflected laser light, the torsion during the vibration process makes the reflected laser light enter different positions of the PSD, and the angle of torsion is measured in real time by detecting the position change of the reflected laser light. This method cannot realize non-contact measurement, the device is huge, and the added specular reflector needs to be fixed on the measured object, which has certain damage to the measured object, and the reflector may also be damaged under dynamic conditions. Since the PSD measurement position range and accuracy cannot meet the requirements at the same time, saturation may occur under dynamic conditions. Therefore, this scheme has great limitations.

With the continuous expansion of the industrial measurement field and the continuous improvement of measurement accuracy and measurement speed, the traditional contact measurement cannot meet the demand. The laser displacement sensor based on the laser triangulation method can realize non-contact measurement. This method has the characteristics of non-contact measurement, no damage to the measured surface, high measurement resolution, high precision, and small size. Based on the above advantages of the laser displacement sensor, it is considered to combine the calibration of the laser displacement sensor and the inertial measurement combination, which can calibrate the inertial measurement combination without contact, and simultaneously measure its pitch angle, yaw angle, and roll angle relative to the initial position. and three-dimensional displacement information.

Contents of the invention

The present invention proposes a non-contact system and method for calibrating the performance of the inertial measurement combination under dynamic conditions based on a laser displacement sensor, which can provide real-time pitch angle, yaw angle, roll angle and 3D displacement information.

Technical scheme of the present invention is as follows:

An optical calibration system for inertial measurement combined dynamic navigation performance includes an optical calibration device, an information collection module, a DSP, a communication interface and a PC, and the information collection module includes a first information collection unit, a second information collection unit and a synchronization module , the first information collection unit collects the displacement data of the three angular displacement measurement components, the second information collection unit collects the data of the inertial measurement combination to be measured, and the synchronization module simultaneously sends a synchronous collection instruction to the information collection module 1 and the information collection module 2, and the information The acquisition module is connected to the DSP, and the DSP is connected to the PC through the communication interface; the optical calibration device includes a horizontal vibration isolation platform, a one-dimensional vibration table, an inertial measurement combination to be measured, a first laser displacement sensor and a second laser displacement sensor. The first angular displacement measurement component, the second angular displacement measurement component composed of the third laser displacement sensor and the fourth laser displacement sensor, the third angular displacement measurement component composed of the fifth laser displacement sensor and the sixth laser displacement sensor; one-dimensional The vibration table is fixed on the surface of the horizontal vibration isolation platform, the three angular displacement measurement components are fixed on the surface of the horizontal vibration isolation platform, the inertial measurement combination to be measured is fixed on the surface of the one-dimensional vibration table, and the three angular displacement measurement components are arranged on the The periphery of the combination is used to measure the three-dimensional displacement, pitch angle, roll angle and yaw angle of the inertial measurement combination to be measured; the one-dimensional vibration table can produce one-dimensional vibration in the Y direction, and its surface is parallel to the XY plane; The inertial measurement unit to be measured has three mutually orthogonal planes, wherein the first plane is parallel to the XZ plane, the second plane is parallel to the XY plane, and the third plane is parallel to the YZ plane.

Further, the first laser displacement sensor and the second laser displacement sensor are parallel to each other and make the two laser beams perpendicularly incident on the first plane of the inertial measurement combination to be measured; the third laser displacement sensor and the fourth laser displacement sensor are mutually Parallel and make the two laser beams vertically incident on the second plane of the inertial measurement combination to be measured; the fifth laser displacement sensor and the sixth laser displacement sensor are parallel to each other and make the two laser beams vertically incident on the third plane of the inertial measurement combination to be measured superior.

The present invention also discloses an optical calibration method of the optical calibration system of the inertial measurement combined dynamic navigation performance, specifically as follows:

The planes where the first laser displacement sensor and the second laser displacement sensor are located in the first angular displacement measurement component are parallel to the XY plane, and the distance between them is L ₁ . The two emitted laser beams are parallel to each other and perpendicular to the measured The first plane of the object, in the initial state, the displacement measured by the first laser displacement sensor is S ₁ ', and the displacement measured by the second laser displacement sensor is S ₂ ', when the inertial measurement combination to be measured rotates around the Z axis time, angle The relationship between the displacement S ₁ measured by the first laser displacement sensor, the displacement S ₂ measured by the second laser displacement sensor and the distance L ₁ between the two laser beams is: By measuring S ₁ , S ₂ and the known L ₁ , measure the motion angle of the inertial measurement unit to be measured around the Z axis in real time, that is, the yaw angle At the same time, the displacement along the Y-axis of the inertial measurement combination to be measured can be obtained

The planes of the third laser displacement sensor and the fourth laser displacement sensor in the second angular displacement measurement component are parallel to the ZY plane, and the distance between them is L ₂ . The two emitted laser beams are parallel to each other and perpendicular to the Measure the second plane of the object. In the initial state, the displacement measured by the third laser displacement sensor is S ₃ ', and the displacement measured by the fourth laser displacement sensor is S ₄ '. When the inertial measurement combination to be measured rotates around the X-axis by an angle When φ, the relationship between the angle φ, the displacement S ₃ measured by the third laser displacement sensor, the displacement S ₄ measured by the fourth laser displacement sensor and the distance L ₂ between the two laser beams is By measuring S ₃ , S ₄ and the known L ₂ , measure the motion angle of the inertial measurement unit to be measured around the X-axis in real time, that is, the roll angle φ, and at the same time obtain the displacement of the inertial measurement unit to be measured along the Z-axis

The planes of the fifth laser displacement sensor and the sixth laser displacement sensor in the third angular displacement measurement component are parallel to the ZX plane, and the distance between them is L ₃ . The two emitted laser beams are parallel to each other and perpendicular to the Measure the third plane of the object. In the initial state, the displacement measured by the fifth laser displacement sensor is S ₅ ′, and the displacement measured by the sixth laser displacement sensor is S ₆ ′. When the inertial measurement combination to be measured rotates around the Y axis by an angle When θ, the relationship between the angle θ, the displacement S ₅ measured by the fifth laser displacement sensor, the displacement S ₆ measured by the sixth laser displacement sensor, and the distance L ₃ between the two laser beams is: By measuring S ₅ , S ₆ and the known L ₃ , measure the motion angle of the inertial measurement unit to be measured around the Z axis in real time, that is, the yaw angle θ, and at the same time obtain the displacement of the inertial measurement unit to be measured along the X axis

The first information collection unit collects the displacement data of the three angular displacement measurement components, the second information collection unit collects the data of the inertial measurement combination to be measured, and the synchronization module sends synchronous collection instructions to the first information collection unit and the second information collection unit at the same time, Realize the real-time synchronous acquisition of 6 laser displacement sensor signals and inertial measurement combined signals, and send the results to the PC, and the PC can obtain the three-dimensional displacement information L _X , L _Y , L _Z and three-dimensional angle information θ, φ, when the one-dimensional shaking table vibrates along the Y axis to test the dynamic conductivity of the inertial measurement unit, the information acquisition module synchronously collects the three-dimensional displacement information Ix, Iy, Iz and three-dimensional angle information output by the inertial measurement unit I _θ , I _φ , comparing the two results, the measurement error of the three-dimensional angle and three-dimensional displacement of the inertial measurement unit under dynamic conditions can be obtained as:

The calibration of the dynamic navigation performance of the inertial measurement combination can be realized, that is, the performance of the inertial measurement combination can be evaluated.

The beneficial effect of the present invention is that the present invention realizes the non-contact optical calibration of the dynamic navigation performance of the inertial measurement combination. The rotation angle, and then use the six-way laser displacement sensor to realize the measurement of the three-dimensional angle and displacement, supplemented by the corresponding mechanical adjustment and alignment device, as well as the information acquisition and processing system, which can calibrate the dynamic performance of the inertial measurement combination in real time. The advantage is that the non-contact measurement is non-destructive to the inertial measurement combination to be tested, and has high measurement accuracy and real-time synchronization, which provides an effective calibration method for the calibration of the dynamic navigation performance of the inertial measurement combination.

Description of drawings

Figure 1 is a diagram of the optical calibration system for the inertial measurement integrated dynamic navigation performance;

Fig. 2 is a block diagram of the information processing of the optical calibration system of the inertial measurement combined dynamic navigation performance.

detailed description

The present invention is described in detail below in conjunction with accompanying drawing.

As shown in Figures 1 and 2, an optical calibration system for inertial measurement combined dynamic navigation performance includes an optical calibration device, an information acquisition module, a DSP, a communication interface, and a PC, and the information acquisition module includes a first information acquisition unit , the second information collection unit and the synchronization module, the first information collection unit collects the displacement data of three angular displacement measurement components, the second information collection unit collects the data of the inertial measurement combination (3) to be measured, and the synchronization module sends information to the information collection module simultaneously The first and the information acquisition module two send synchronous acquisition instructions, the information acquisition module is connected to the DSP, and the DSP is connected to the PC through the communication interface; the optical calibration device includes a horizontal vibration isolation platform 1, a one-dimensional vibration table 2, an inertial measurement unit to be measured Combination 3, the first angular displacement measurement assembly 13 composed of the first laser displacement sensor 4 and the second laser displacement sensor 5, the second angular displacement measurement assembly 14 composed of the third laser displacement sensor 6 and the fourth laser displacement sensor 7, the first The third angular displacement measurement component 15 composed of five laser displacement sensors 8 and the sixth laser displacement sensor 9; the one-dimensional vibration table 2 is fixed on the surface of the horizontal vibration isolation platform 1, and the three angular displacement measurement components are fixed on the surface of the horizontal vibration isolation platform 1 , the inertial measurement unit 3 to be measured is fixed on the surface of the one-dimensional vibrating table 2, and three angular displacement measurement components are arranged around the inertial measurement unit 3 to measure the three-dimensional displacement, pitch angle, and roll of the inertial measurement unit 3 to be measured. Rotation angle and yaw angle; the one-dimensional vibrating table 2 can produce one-dimensional vibration in the Y direction, and its surface is parallel to the XY plane; the described inertial measurement combination 3 to be measured has three mutually orthogonal planes, wherein the first The plane 10 is parallel to the XZ plane, the second plane 11 is parallel to the XY plane, and the third plane 12 is parallel to the YZ plane.

The first laser displacement sensor 4 and the second laser displacement sensor 5 are parallel to each other and make the two laser beams perpendicularly incident on the first plane 10 of the inertial measurement combination 3 to be measured; the third laser displacement sensor 6 and the fourth laser displacement sensor The sensors 7 are parallel to each other and make the two laser beams perpendicularly incident on the second plane 11 of the inertial measurement combination 3 to be measured; the fifth laser displacement sensor 8 and the sixth laser displacement sensor 9 are parallel to each other and make the two laser beams perpendicularly incident on the second plane 11 of the inertial measurement combination 3 to be measured; On the third plane 12 of the IMU 3 .

The optical calibration method of the optical calibration system of the inertial measurement combined dynamic navigation performance is as follows:

The plane where the first laser displacement sensor 4 and the second laser displacement sensor 5 are located in the first angular displacement measurement component 13 is parallel to the XY plane, and the distance between them is L ₁ . The two emitted laser beams are parallel to each other and vertical in the initial state. On the first plane 10 of the object to be measured, in the initial state, the displacement measured by the first laser displacement sensor 4 is S ₁ ', and the displacement measured by the second laser displacement sensor 5 is S ₂ ', when the inertial measurement combination to be measured 3 rotation angle around the Z axis time, angle The relationship between the displacement S1 measured by the first laser displacement sensor ₄ , the displacement S2 measured by the _second laser displacement sensor ₅ , and the distance L1 between the two laser beams is as follows: By measuring S ₁ , S ₂ and the known L ₁ , measure the motion angle of the inertial measurement unit 3 to be measured around the Z axis in real time, that is, the yaw angle At the same time, the displacement of the inertial measurement unit 3 to be measured along the Y axis can be obtained

The planes where the third laser displacement sensor 6 and the fourth laser displacement sensor 7 are located in the second angular displacement measurement assembly 14 are parallel to the ZY plane, the distance between them is L ₂ , and the two emitted laser beams are parallel to each other, and in the initial state Perpendicular to the second plane 11 of the object to be measured, in the initial state, the displacement measured by the third laser displacement sensor 6 is S ₃ ′, and the displacement measured by the fourth laser displacement sensor 7 is S ₄ ′, when the inertial measurement to be measured When the combination 3 rotates the angle φ around the X axis, the relationship between the angle φ, the displacement S ₃ measured by the third laser displacement sensor 6, the displacement S ₄ measured by the fourth laser displacement sensor 7, and the distance L ₂ between the two laser beams for By measuring S ₃ , S ₄ and the known L ₂ , the movement angle of the inertial measurement unit 3 to be measured around the X-axis is measured in real time, that is, the roll angle φ, and the displacement of the inertial measurement unit 3 to be measured along the Z-axis can be obtained at the same time

The planes where the fifth laser displacement sensor 8 and the sixth laser displacement sensor 9 are located in the third angular displacement measurement assembly 15 are parallel to the ZX plane, the distance between them is L ₃ , and the two emitted laser beams are parallel to each other, and in the initial state Perpendicular to the third plane 12 of the object to be measured, in the initial state, the displacement obtained by the measurement 8 of the fifth laser displacement sensor is S ₅ ′, and the displacement obtained by the measurement of the sixth laser displacement sensor 9 is S ₆ ′, when the inertial measurement to be measured When the combination 3 rotates the angle θ around the Y axis, the relationship between the angle θ, the displacement S ₅ measured by the fifth laser displacement sensor 8 , the displacement S ₆ measured by the sixth laser displacement sensor 9 , and the distance L ₃ between the two laser beams for By measuring S ₅ , S ₆ and the known L ₃ , measure the motion angle of the inertial measurement unit 3 to be measured around the Z axis in real time, that is, the yaw angle θ, and at the same time obtain the displacement of the inertial measurement unit 3 to be measured along the X axis

The first information collection unit collects the displacement data of the three angular displacement measurement components, the second information collection unit collects the data of the inertial measurement combination (3) to be measured, and the synchronization module simultaneously sends synchronization to the first information collection unit and the second information collection unit Acquisition instructions to realize real-time synchronous acquisition of 6 laser displacement sensor signals and inertial measurement combined signals, and send the results to the PC, and the PC can obtain three-dimensional displacement information L _X , L _Y , L _Z and three-dimensional angle information θ, φ, when the one-dimensional shaking table vibrates along the Y axis to test the dynamic conductivity of the inertial measurement unit, the information acquisition module synchronously collects the three-dimensional displacement information Ix, Iy, Iz and three-dimensional angle information output by the inertial measurement unit I _θ , I _φ , comparing the two results, the measurement error of the three-dimensional angle and three-dimensional displacement of the inertial measurement unit under dynamic conditions can be obtained as:

The calibration of the dynamic navigation performance of the inertial measurement combination can be realized, that is, the performance of the inertial measurement combination can be evaluated.

Claims (3)

1. the optical calibrating system of the dynamic navigation performance of IMU, it is characterised in that comprise optical calibrating device, Information acquisition module, DSP, communication interface and PC, described information acquisition module includes first information collecting unit, the second letter Breath collecting unit and synchronization module, the displacement data of three angle displacements measurement assemblies of first information collecting unit collection, second Information acquisition unit gathers the data of IMU to be measured (3), and synchronization module is simultaneously to information acquisition module one and information Acquisition module two sends synchronous acquisition instruction, and information acquisition module is connected with DSP, and DSP is connected with PC by communication interface；Institute The optical calibrating device stated include horizontal seismic isolation platform (1), one-dimensional vibration table (2), IMU to be measured (3), first swash The first angle displacement that Optical displacement sensor (4) and the second laser displacement sensor (5) form measures assembly (13), the 3rd laser The second angle displacement that displacement transducer (6) and the 4th laser displacement sensor (7) form measures assembly (14), the 5th laser position Third angle displacement measurement assembly (15) that displacement sensor (8) and the 6th laser displacement sensor (9) form；One-dimensional vibration table (2) being fixed on horizontal seismic isolation platform (1) surface, three angle displacements are measured assembly and are fixed on horizontal seismic isolation platform (1) surface, treat Surveying IMU (3) and be fixed on the surface of one-dimensional vibration table (2), three angle displacements are measured assembly and are arranged in inertia to be measured The surrounding measuring combination (3) is used for measuring the three-D displacement of IMU to be measured (3), the angle of pitch, roll angle and yaw angle； Described one-dimensional vibration table (2) can produce one-dimensional vibration in the Y direction, and its surface is parallel to X/Y plane；Described inertia to be measured is surveyed Amount combination (3) has three mutually orthogonal planes, and wherein the first plane (10) is parallel to XZ plane, and the second plane (11) is parallel to X/Y plane, the 3rd plane (12) is parallel to YZ plane.

2. optical calibrating device as claimed in claim 1, it is characterised in that described the first laser displacement sensor (4) and the Dual-laser displacement transducer (5) is parallel to each other and makes two bundle laser vertical incide the of IMU to be measured (3) In one plane (10)；3rd laser displacement sensor (6) and the 4th laser displacement sensor (7) are parallel to each other and make two bundles Laser vertical incides in second plane (11) of IMU to be measured (3)；5th laser displacement sensor (8) and the 6th Laser displacement sensor (9) is parallel to each other and makes two bundle laser vertical incide the 3rd of IMU to be measured (3) In plane (12).

3. the optical calibration method of an optical calibrating system as claimed in claim 1, it is characterised in that the first angle displacement is surveyed In amount assembly (13), to be parallel to XY flat for the first laser displacement sensor (4) and the plane residing for the second laser displacement sensor (5) Face, its spacing is L₁, two bundle laser of outgoing are parallel to each other, and are perpendicular to the first plane of object under test in an initial condition (10), under original state, the displacement that the first laser displacement sensor measurement (4) obtains is S₁', the second laser displacement sensor (5) measuring the displacement obtained is S₂', when IMU to be measured (3) turns about the Z axis angleTime, angleFirst laser position Displacement sensor (4) measures the displacement S obtained₁, the second laser displacement sensor (5) measure the displacement S that obtains₂With two laser it Between distance L₁Relation beBy measuring S₁、S₂With known L₁, measure inertia measurement to be measured in real time Combination (3) movement angle about the z axis, i.e. yaw angleCan get the IMU to be measured (3) displacement along Y-axis simultaneously

Second angle displacement measures the 3rd laser displacement sensor (6) and the 4th laser displacement sensor (7) in assembly (14) Residing plane is parallel to ZY plane, and its spacing is L₂, two bundle laser of outgoing are parallel to each other, and the most vertical In second plane (11) of object under test, under original state, it is S that the 3rd laser displacement sensor (6) measures the displacement obtained₃', It is S that 4th laser displacement sensor (7) measures the displacement obtained₄', when IMU to be measured (3) turns about the X axis angle φ Time, angle φ, the 3rd laser displacement sensor (6) measure the displacement S obtained₃, the 4th laser displacement sensor (7) measure obtain Displacement S₄And distance L between two laser₂Relation beBy measuring S₃、S₄With known L₂, Measure the IMU to be measured (3) movement angle around X-axis, i.e. roll angle φ in real time, can get inertia measurement to be measured simultaneously Combination (3) is along the displacement of Z axis

5th laser displacement sensor (8) and the 6th laser displacement sensor (9) in third angle displacement measurement assembly (15) Residing plane is parallel to ZX plane, and its spacing is L₃, two bundle laser of outgoing are parallel to each other, and the most vertical In the 3rd plane (12) of object under test, under original state, it is S that the 5th laser displacement sensor (8) measures the displacement obtained₅', It is S that 6th laser displacement sensor (9) measures the displacement obtained₆', when IMU to be measured (3) is around Y-axis rotational angle θ Time, angle, θ, the 5th laser displacement sensor (8) measure the displacement S obtained₅, the 6th laser displacement sensor (9) measure obtain Displacement S₆And distance L between two laser₃Relation beBy measuring S₅、S₆With known L₃, Measure IMU to be measured (3) movement angle about the z axis, i.e. yaw angle θ in real time, can get inertia measurement group to be measured simultaneously Close (3) displacement along X-axis

First information collecting unit gathers three angle displacements and measures the displacement data of assembly, and the second information acquisition unit collection is treated Surveying the data of IMU (3), synchronization module sends to first information collecting unit and the second information acquisition unit simultaneously Synchronous acquisition instructs, it is achieved 6 laser displacement sensor signals and the real-time synchronization collection of IMU signal, and handle Result delivers to PC, and PC obtains three-D displacement information L_X, L_Y, L_ZWith three-dimensional perspective informationθ, φ, when one-dimensional vibration table is along Y Shaft vibration is in order to test when dynamically leading performance of IMU, and information acquisition module synchronous acquisition IMU exports Three-D displacement information Ix, Iy, Iz and three-dimensional perspective informationI_θ, I_φ, two results are compared, i.e. can get inertia measurement The measurement error combining three-dimensional perspective and three-D displacement in a dynamic condition is:

The demarcation of the dynamic navigation performance of IMU can be realized, i.e. the performance of IMU is made evaluation.