Deformation dynamic testing device based on six-degree-of-freedom table and use method

Abstract

The invention discloses a deformation dynamic testing device based on a six-degree-of-freedom table and a use method, and the device comprises a first six-degree-of-freedom table which generates dynamic excitation, and the upper surface of the first six-degree-of-freedom table is provided with a first end part and a second end part which are opposite to each other; an easy stress deformation flat plate and a second six-degree-of-freedom table are arranged on the first end part and the second end part respectively; a first deformation measuring device is rigidly connected to the easy stress deformation flat plate, a second end part is rigidly connected with a second six-degree-of-freedom table of which the size is smaller than that of the first degree-of-freedom table, and a second deformation measuring device is rigidly connected to the second six-degree-of-freedom table; a second autocollimator parallel to the first deformation measuring device is rigidly connected to the easy stress deformation flat plate; determining a connecting line between the first deformation measuring device and the second deformation measuring device, wherein the direction of the second autocollimator is parallel to the direction of the connecting line; a first autocollimator is arranged on the flat plate prone to stress deformation in the direction perpendicular to the connecting line; and the hexahedral prism is rigidly connected to the second six-degree-of-freedom table through an L-shaped switching tool.

Description

Technical Field

[0001] The present invention relates to the technical field of attitude measurement of an inertial navigation system, and in particular to a deformation dynamic testing device based on a six-degree-of-freedom platform and a use method thereof. Background Art

[0002] Attitude measurement in an inertial navigation system is a means of stably tracking the absolute attitude of a measurement carrier under long-term conditions. If absolute attitude monitoring is performed synchronously at two different locations on a carrier, the relative change is the deformation of the carrier, which is an important basis for analyzing structural stability. Current tests of deformation measurement equipment are performed under static conditions. Optical transfer datums are established at two locations of relative deformation to be measured, and the conversion relationship between the two optical datums, i.e., the deformation reference value, is determined using equipment such as a theodolite or total station. The actual measurement results of the deformation measurement device are then evaluated based on this value. It can be seen that static conditions have the following deficiencies: (1) They cannot reflect the responsiveness of the deformation measurement device under dynamic conditions; (2) There is an installation error when the optical transfer datum is drawn out, so the deformation reference value is not very accurate.

[0003] There are few tests on deformation under dynamic conditions in the prior art. Some dynamic tests of deformation measurement are also carried out in the field on carriers such as ships and vehicles in actual application. Although such tests can fully cover the environmental conditions during real work, their measurement results can only be qualitative verification tests of their functions because there is no real reference value for deformation.

[0004] In summary, for deformation measuring devices, there is currently no good test method to evaluate the accuracy of their measurements due to installation errors under static conditions; and further, under dynamic conditions, there is no test method for the response capability of deformation measurement. Summary of the invention

[0005] In view of this, the present invention provides a deformation dynamic testing device based on a six-degree-of-freedom platform and a method of use, which can solve the technical problem that the prior art cannot perform dynamic testing.

[0006] In order to solve the above technical problems, the present invention is implemented as follows.

[0007] A deformation dynamic testing device based on a six-degree-of-freedom platform, comprising:

[0008] A first six-degree-of-freedom platform for generating dynamic excitation, wherein the upper surface of the first six-degree-of-freedom platform has a first end, a second end, and a third end adjacent to both the first end and the second end; a stress-prone deformation plate is disposed on the first end and the third end, and a second six-degree-of-freedom platform is disposed on the second end; a first deformation measuring device is rigidly connected to the stress-prone deformation plate, and the second end is rigidly connected to a second six-degree-of-freedom platform whose size is smaller than that of the first degree-of-freedom platform, and the second deformation measuring device is rigidly connected to the second six-degree-of-freedom platform; a second autocollimator parallel to the first deformation measuring device is rigidly connected to the stress-prone deformation plate; a connecting line between the first deformation measuring device and the second deformation measuring device is determined, and the direction of the second autocollimator is parallel to the connecting line direction; the first autocollimator is disposed on the stress-prone deformation plate in a direction perpendicular to the connecting line; and a hexahedral prism is rigidly connected to the second six-degree-of-freedom platform through an L-shaped adapter fixture.

[0009] Preferably, the first autocollimator is used to provide a deformation component reference in the roll axis direction; and the second autocollimator is used to provide a deformation component reference in the pitch axis direction.

[0010] Preferably, the deformation dynamic testing device based on the six-degree-of-freedom platform performs initial data calibration at the initial stage, including:

[0011] The second six-degree-of-freedom platform performs a static deformation zero position setting so that the first deformation measuring device and the second deformation measuring device produce relative deformations that meet preset requirements in a static state; the posture indications of the first deformation measuring device and the second deformation measuring device, as well as the indications of the second autocollimator and the first autocollimator are recorded, and the indications of the second autocollimator and the first autocollimator are used as static reference values.

[0012] The first six-degree-of-freedom platform performs motion simulation to generate disturbances of forces on the stress-prone deformable plate caused by different postures under dynamic conditions, and records the posture indications of the first deformation measuring device and the second deformation measuring device, as well as the indications of the first autocollimator and the second autocollimator while keeping the time synchronization of the first deformation measuring device and the second deformation measuring device; the indications of the first autocollimator and the second autocollimator are used as the true value benchmark of the dynamic deformation.

[0013] Preferably, a reference coordinate system is established for the deformation dynamic testing device, and the reference coordinate system includes a first reference coordinate system O GND -X GND Y GND Z GND , the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 , the third reference coordinate system O INT2 -X INT2Y INT2 Z INT2 , the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI , the fifth reference coordinate system O OBS -X OBS Y OBS Z OBS , where the first reference coordinate system O GND -X GND Y GND Z GND is the north-east inertial coordinate system of the test site where the deformation dynamic test device is located, that is, a right-handed system constructed by the local true north and the horizon of the test site; the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 is the measurement reference system of the first deformation measuring device, X INT1 Axis, Y INT1 Axis and Z INT1 The axes correspond to the roll axis, azimuth axis and pitch axis of the first deformation measuring device respectively; the third reference coordinate system O INT2 -X INT2 Y INT2 Z INT2 is the measurement reference system of the second deformation measuring device, X INT2 Axis, Y INT2 Axis and Z INT2 The axes correspond to the roll axis, azimuth axis and pitch axis of the second deformation measuring device respectively; the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI The three mutually orthogonal normals of the hexahedron are used as coordinate axes; the fifth reference coordinate system O OBS -X OBS Y OBS Z OBS It is a reference coordinate system that represents the observation of the hexahedron by two autocollimators, and the initial directions of its coordinate axes are the same as those of the second reference coordinate system.

[0014] Preferably, the dynamic excitation generated by the first six-degree-of-freedom platform simulates the mechanical excitation under sea conditions or road conditions, thereby generating a dynamic deformation.

[0015] The present invention provides a method for dynamic testing of deformation based on a six-degree-of-freedom platform, based on the above-mentioned dynamic testing device for deformation based on a six-degree-of-freedom platform, comprising:

[0016] Step S31: The second six-degree-of-freedom platform generates the relative deformation R of the first deformation measuring device and the second deformation measuring device in a static state. INT12INT20 ; Determine the reading (θ of the first autocollimator ROLL0X ,θ ROLL0Y ) is its zero offset value in azimuth and elevation, and the reading (θ PITCH0X ,θ PITCH0Y ) is the zero offset value in azimuth and elevation, and there is a static measurement relationship

[0017]

[0018] Among them, R INT22PRI is the transformation matrix between the third reference coordinate system and the fourth reference coordinate system, R OBS2INT1 is the transformation matrix between the second reference coordinate system and the fifth reference coordinate system;

[0019] Step S32: Obtain the static zero position measurement result R of the first deformation measuring device INT12GND0 , the static zero position measurement result R of the second deformation measuring device INT22GND0 , then the following relationship exists:

[0020] R INT12INT20 =R Τ INT22GND0 ·R INT12GND0 ;

[0021] Step S33: Under static conditions, adjust the second six-degree-of-freedom platform to produce different tilt angles, perform the following operation once for each tilt angle, and update an i value each time:

[0022] After adjustment, the relative posture conversion relationship between the first deformation measuring device and the second deformation measuring device is obtained, which is recorded as R INT12INT2i Based on the indications of the first autocollimator and the second autocollimator, the conversion relationship R between the fourth reference coordinate system and the fifth reference coordinate system is obtained. OBS2PRIi ; Get the reading of the second autocollimator at this time, recorded as (θ PITCHiX ,θ PITCHiY ), where θ PITCHiX is the deflection angle of the pitch axis of the hexahedron in the azimuth direction, θ PITCHiY is the deflection angle of the pitch axis of the hexahedron in the pitch direction; the reading of the first autocollimator at this time is obtained, recorded as (θ ROLLiX ,θ ROLLiY ), where θ ROLLiX is the deflection angle of the roll axis of the hexahedron in the azimuth direction, θ ROLLiY is the deflection angle of the roll axis of the hexahedron in the pitch direction; at this time, the XPRI The axis is expressed in the fifth reference coordinate system as:

[0023]

[0024] The fourth reference coordinate system X PRI The axis is expressed in the fifth reference coordinate system as:

[0025]

[0026] Calculate the Y of the fourth reference coordinate system PRI Representation of the axis in the fifth reference coordinate system:

[0027]

[0028] Then the transformation relationship R between the fifth reference coordinate system and the fourth reference coordinate system is OBS2PRIi It is expressed as:

[0029]

[0030] Step S34: Based on all R OBS2PRIi , use arithmetic mean and orthogonalization to determine R OBS2PRI

[0031]

[0032] Step S35: Calculate the fixed transformation matrix R OBS2INT1 and R INT22PRI ,include:

[0033] Step S351: Determine the deformation of the upper surface of the stress-deformable plate monitored by the first deformation measuring device and the upper surface of the second six-degree-of-freedom platform monitored by the second deformation measuring device:

[0034] R INT12INT2 =R Τ INT22GND R INT12GND ;

[0035] Step S352: Solve the fixed transformation matrix R based on the following formula OBS2INT1 and R INT22PRI :

[0036] R INT22PRI R INT12INT2 R OBS2INT1 =R OBS2PRI

[0037]

[0038] Step S36: taking the angle maintained by the first six-degree-of-freedom platform during the dynamic test as the reference position for deformation measurement, performing motion simulation on the first six-degree-of-freedom platform to generate different postures so as to generate deformation disturbance on the stress-prone deformable plate, obtaining the posture data of the first deformation measuring device and the second deformation measuring device at the same time sampling point and the indications of the first autocollimator and the second autocollimator while keeping the time synchronization of the first deformation measuring device and the second deformation measuring device; fitting the outputs of the first deformation measuring device, the second deformation measuring device, the first autocollimator and the second autocollimator respectively based on the corresponding sampling point data, and obtaining the output curve of the first deformation measuring device, the output curve of the second deformation measuring device, the output curve of the first autocollimator and the output curve of the second autocollimator;

[0039] Step S37: Based on the output curve of the first deformation measuring device and the output curve of the second deformation measuring device, the deformation amount R between the first deformation measuring device and the second deformation measuring device at the jth moment is obtained. INT12INT2j , based on R OBS2PRI , determine R OBS2PRIj ;According to the fixed conversion relationship, the reference value of the deformation at that moment is obtained

[0040]

[0041] Step S38: R INT12INT2j and benchmark value Expanding on the three Euler angle components, we get the measurement error;

[0042] Step S39: Based on the measurement error and its decomposition in different axis directions, the dynamic performance of the deformation dynamic testing device based on the six-degree-of-freedom table is determined.

[0043] The present invention provides a computer-readable storage medium, wherein a plurality of instructions are stored in the storage medium; the plurality of instructions are used for a processor to load and execute the method as described above.

[0044] An electronic device provided by the present invention is characterized in that the electronic device comprises:

[0045] A processor, which is used to execute multiple instructions;

[0046] A memory for storing a plurality of instructions;

[0047] The plurality of instructions are used to be stored in the memory and loaded and executed by the processor as described above.

[0048] Beneficial effects:

[0049] (1) The present invention uses a small six-degree-of-freedom platform to establish the initial relative relationship between the two measuring ends of the deformation under static conditions; uses a large six-degree-of-freedom platform and a deformation generating pad at one measuring end to simulate the change of deformation under dynamic conditions; uses two dual-axis autocollimators fixed to one measuring end and an optical hexahedron fixed to the other measuring end to accurately measure the deformation. The test process is divided into two stages, static and dynamic. The test is essentially only performed on the change of deformation under dynamic conditions; there is no optical transfer calculation in the whole process, and the reference system relationship is only solved by the model, so it can effectively avoid the influence of random installation errors on the test results. The excitation of the deformation dynamic test comes from the large six-degree-of-freedom platform, which can well simulate the actual dynamic conditions of vehicles and ships.

[0050] (2) The present invention is applied to the field of inertial attitude measurement, and specifically to the dynamic test link based on the deformation measurement of inertial devices. During the test, two six-degree-of-freedom mechanical excitations are used to generate static deformation and dynamic deformation respectively, pads of different materials are used to generate simulated responses of dynamic deformation, and a high-precision photoelectric autocollimator is used to generate monitoring true values ​​of dynamic deformation. During the test, the initial deformation between the inertial groups is first recorded through static observation for a period of time, and the static reading of the photoelectric autocollimator is recorded at the same time; then, the dynamic excitation six-degree-of-freedom platform is used to generate attitude changes of different amplitudes. During the dynamic force change process, the pad will produce different real-time deformations. The present invention can simulate the structural deformation caused by dynamic environment, especially wave conditions and road transportation conditions, and give real-time true values, so it can provide an effective test for the real-time response characteristics of deformation measurement.

[0051] (3) The present invention generates stress-driven excitation and initial value of dynamic deformation through large and small six-degree-of-freedom stages, and detects the change of deformation in real time through an autocollimator. Mathematical transfer is used throughout the calculation process, avoiding installation errors introduced by optical reference transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a structural schematic diagram of a deformation dynamic testing device based on a six-degree-of-freedom platform of the present invention;

[0053] Figure 2 It is a schematic diagram of the coordinate system of the deformation dynamic testing device based on the six-degree-of-freedom platform of the present invention.

[0054] Reference numerals:

[0055] 1. First deformation measuring device; 2. Second deformation measuring device; 3. First six-degree-of-freedom platform; 4. Second six-degree-of-freedom platform; 5. Stress-deformable plate; 6. Hexahedral prism; 7. Second autocollimator; 8. First autocollimator. DETAILED DESCRIPTION

[0056] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0057] The invention proposes a deformation dynamic testing device based on a six-degree-of-freedom platform.

[0058] like Figure 1 As shown, the deformation dynamic testing device based on the six-degree-of-freedom platform provided by the present invention comprises:

[0059] A first six-degree-of-freedom platform 3 for generating dynamic excitation, wherein the upper surface 3 of the first six-degree-of-freedom platform has a first end, a second end, and a third end adjacent to the first end and the second end; a stress-deformable flat plate 5 is disposed on the first end and the third end, and a second six-degree-of-freedom platform 4 is disposed on the second end;

[0060] The first deformation measuring device 1 is rigidly connected to the stress-prone deformation plate 5, the second end is rigidly connected to the second six-degree-of-freedom platform 4 whose size is smaller than the first degree-of-freedom platform 3, and the second deformation measuring device 2 is rigidly connected to the second six-degree-of-freedom platform 4; the second autocollimator 7 parallel to the first deformation measuring device 1 is rigidly connected to the stress-prone deformation plate 5; the connecting line between the first deformation measuring device 1 and the second deformation measuring device 2 is determined, and the direction of the second autocollimator 7 is parallel to the connecting line direction; the first autocollimator 8 is deployed on the stress-prone deformation plate 5 in a direction perpendicular to the connecting line; the first autocollimator 8 is used to provide a deformation component benchmark in the roll axis direction; the second autocollimator 7 is used to provide a deformation component benchmark in the pitch axis direction; the hexahedral prism 6 is rigidly connected to the second six-degree-of-freedom platform 4 through an L-shaped adapter fixture.

[0061] The second six-degree-of-freedom platform 4 generates the relative deformation of the first deformation measuring device 1 and the second deformation measuring device 2 in a static state; the first six-degree-of-freedom platform 3 can perform motion simulation, and is used to generate different force changes under different posture conditions, thereby inducing the stress-sensitive deformation plate 5 to dynamically generate different deformations. The hexahedral prism 6, the first autocollimator 8 and the second autocollimator 7 are used to monitor the true value of the actual dynamic deformation, and thereby evaluate the measurement accuracy of the dynamic deformation generated by the first deformation measuring device 1 and the second deformation measuring device 2.

[0062] The present invention utilizes the dynamic excitation generated by the first six-degree-of-freedom platform 3 to simulate the mechanical excitation under sea conditions or road conditions, thereby generating dynamic deformation. The reference value benchmark of the dynamic deformation is generated by continuous detection of the hexahedral prism 6 by the autocollimator. In the present invention, except for the stress-deformable plate 5, the other structures are rigidly connected, and the structural deformation will not change with the dynamic conditions. The stress-deformable plate 5 and the first deformation measuring device 1 installed thereon are affected by the movement of the first six-degree-of-freedom platform 3, and the deformation will change dynamically. This change will be reflected by the hexahedral prism 6 rigidly connected to the second deformation measuring device 1. The above changes can also be obtained by the second autocollimator 7 and the first autocollimator 8.

[0063] The deformation dynamic testing device based on the six-degree-of-freedom platform performs initial data calibration at the initial stage, including:

[0064] The second six-degree-of-freedom platform 4 performs a static deformation zero position setting, so that the first deformation measuring device 1 and the second deformation measuring device 2 produce relative deformations that meet preset requirements in a static state; the attitude indications of the first deformation measuring device 1 and the second deformation measuring device 2, as well as the indications of the second autocollimator 7 and the first autocollimator 8 are recorded, and the indications of the second autocollimator 7 and the first autocollimator 8 are used as static reference values;

[0065] The first six-degree-of-freedom platform 3 performs motion simulation to generate the disturbance of the stress-prone deformable plate 5 caused by the forces in different postures under dynamic conditions. While keeping the time synchronization of the first deformation measuring device 1 and the second deformation measuring device 2, the posture indications of the first deformation measuring device 1 and the second deformation measuring device 2, as well as the indications of the first autocollimator 8 and the second autocollimator 7 are recorded; the indications of the first autocollimator 8 and the second autocollimator 7 are used as the true value benchmark of the dynamic deformation.

[0066] Furthermore, a reference coordinate system is established for the deformation dynamic testing device, and the reference coordinate system includes a first reference coordinate system O GND -X GND Y GND Z GND , the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 , the third reference coordinate system O INT2 -X INT2 Y INT2 Z INT2 , the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI , the fifth reference coordinate system O OBS -X OBSY OBS Z OBS , where the first reference coordinate system O GND -X GND Y GND Z GND is the north-east inertial coordinate system of the test site where the deformation dynamic test device is located, that is, a right-handed system constructed by the local true north and the horizon of the test site; the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 is the measurement reference system of the first deformation measuring device 1, X INT1 Axis, Y INT1 Axis and Z INT1 The axes correspond to the roll axis, azimuth axis and pitch axis of the first deformation measuring device 1 respectively; the third reference coordinate system O INT2 -X INT2 Y INT2 Z INT2 is the measurement reference system of the second deformation measuring device 2, X INT2 Axis, Y INT2 Axis and Z INT2 The axes correspond to the roll axis, azimuth axis and pitch axis of the second deformation measuring device 2 respectively; the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI The three mutually orthogonal normal lines of the hexahedral prism 6 are used as coordinate axes; the fifth reference coordinate system O OBS -X OBS Y OBS Z OBS It is a reference coordinate system that represents the observation of the hexahedral prism 6 by two autocollimators, and the initial directions of its coordinate axes are the same as those of the second reference coordinate system.

[0067] The fourth reference coordinate system O PRI -X PRI Y PRI Z PRI The initial directions of the coordinate axes are roughly the same as the coordinate axes of the second reference coordinate system, which represents the change of the posture on the second end; the fifth reference coordinate system represents the change of the posture on the third end, which includes the deformation information to be measured.

[0068] The present invention also provides a method for dynamic testing of deformation based on a six-degree-of-freedom platform. Based on the above-mentioned dynamic testing device for deformation based on a six-degree-of-freedom platform, the method comprises:

[0069] Step S31: The second six-degree-of-freedom platform 4 generates the relative deformation R of the first deformation measuring device 1 and the second deformation measuring device 2 in a static state.INT12INT20 ; Determine the reading (θ of the first autocollimator 8 ROLL0X ,θ ROLL0Y ) is its zero position offset value in azimuth and elevation, and the reading (θ PITCH0X ,θ PITCH0Y ) is the zero offset value in azimuth and elevation, and there is a static measurement relationship

[0070]

[0071] Among them, R INT22PRI is the transformation matrix between the third reference coordinate system and the fourth reference coordinate system, R OBS2INT1 is the transformation matrix between the second reference coordinate system and the fifth reference coordinate system;

[0072] In this embodiment, it is determined that the fourth reference system coincides with the fifth reference system, and the non-coincident part is transferred into the transformation matrix R between the third reference coordinate system and the fourth reference coordinate system according to the Rodriguez law. INT22PRI Or the transformation matrix R of the second and fifth coordinate systems OBS2INT1 Based on the fact that the fourth and fifth coordinate systems coincide under the static condition, the static measurement relationship can be determined.

[0073] Step S32: Obtain the static zero position measurement result R of the first deformation measuring device 1 INT12GND0 , the static zero position measurement result R of the second deformation measuring device 2 INT22GND0 , then the following relationship exists:

[0074] R INT12INT20 =R Τ INT22GND0 ·R INT12GND0 ;

[0075] Step S33: Under static conditions, the second six-degree-of-freedom platform 4 is adjusted to produce different tilt angles, and the following operation is performed once for each tilt angle, and an i value is updated each time the operation is performed:

[0076] After adjustment, the relative posture conversion relationship between the first deformation measuring device 1 and the second deformation measuring device 2 is obtained, which is recorded as R INT12INT2i Based on the indications of the first autocollimator 8 and the second autocollimator 7, the conversion relationship R between the fourth reference coordinate system and the fifth reference coordinate system is obtained. OBS2PRIi ; Get the reading of the second autocollimator 7 at this time, recorded as (θ PITCHiX ,θ PITCHiY ), where θ PITCHiX is the deflection angle of the pitch axis of the hexahedral prism 6 in the azimuth direction, θ PITCHiYis the deflection angle of the pitch axis of the hexagonal prism 6 in the pitch direction; the reading of the first autocollimator 8 at this time is obtained, recorded as (θ ROLLiX ,θ ROLLiY ), where θ ROLLiX is the deflection angle of the roll axis of the hexagonal prism 6 in the azimuth direction, θ ROLLiY is the deflection angle of the roll axis of the hexahedral prism 6 in the pitch direction; at this time, the X PRI The axis is expressed in the fifth reference coordinate system as:

[0077]

[0078] The fourth reference coordinate system X PRI The axis is expressed in the fifth reference coordinate system as:

[0079]

[0080] Calculate the Y of the fourth reference coordinate system PRI Representation of the axis in the fifth reference coordinate system:

[0081]

[0082] Then the transformation relationship R between the fifth reference coordinate system and the fourth reference coordinate system is OBS2PRIi It is expressed as:

[0083]

[0084] Step S34: Based on all R OBS2PRIi , use arithmetic mean and orthogonalization to determine R OBS2PRI

[0085]

[0086] In this embodiment, R OBS2PRI The derivation process is:

[0087]

[0088]

[0089] Step S35: Calculate the fixed transformation matrix R OBS2INT1 and R INT22PRI ,include:

[0090] Step S351: Determine the deformation of the upper surface of the stress-deformable plate 5 monitored by the first deformation measuring device 1 and the upper surface of the second six-degree-of-freedom platform 4 monitored by the second deformation measuring device 2 as follows:

[0091] R INT12INT2 =RΤ INT22GND R INT12GND

[0092] Step S352: Solve the fixed transformation matrix R based on the following formula OBS2INT1 and R INT22PRI :

[0093] R INT22PRI R INT12INT2 R OBS2INT1 =R OBS2PRI

[0094]

[0095] Step S36: the angle maintained by the first six-degree-of-freedom platform 3 during the dynamic test is used as the reference position for deformation measurement, the first six-degree-of-freedom platform 3 performs motion simulation, generates different postures, and thus generates deformation disturbances to the stress-deformable plate 5, and obtains the posture data of the first deformation measuring device 1 and the second deformation measuring device 2 at the same time sampling point while maintaining the time synchronization of the first deformation measuring device 1 and the second deformation measuring device 2, and the indications of the first autocollimator 8 and the second autocollimator 7; based on the corresponding sampling point data, the outputs of the first deformation measuring device 1, the second deformation measuring device 2, the first autocollimator 8, and the second autocollimator 7 are respectively fitted to obtain the output curves of the first deformation measuring device 1, the second deformation measuring device 2, the first autocollimator 8, and the second autocollimator 7;

[0096] Step S37: Based on the output curve of the first deformation measuring device 1 and the output curve of the second deformation measuring device 2, the deformation amount R between the first deformation measuring device 1 and the second deformation measuring device 2 at the jth moment is obtained. INT12INT2j , based on R OBS2PRI , determine R OBS2PRIj ;According to the fixed conversion relationship, the reference value of the deformation at that moment is obtained

[0097]

[0098] Step S38: R INT12INT2j and benchmark value Expanding on the three Euler angle components, we get the measurement error;

[0099] Step S39: Based on the measurement error and its decomposition in different axis directions, the dynamic performance of the deformation dynamic testing device based on the six-degree-of-freedom table is determined.

[0100] The invention provides a specific embodiment of a deformation dynamic testing method based on a six-degree-of-freedom platform.

[0101] 1. Static test

[0102] First, adjust the device under static conditions: (1) Make the dynamic excitation six-degree-of-freedom table in a roughly horizontal position and stabilize it; (2) According to the deformations measured by the first measuring end and the tail measuring end of the deformation measuring device, select a suitable initial value of the static deformation in coordination with the adjustment of the six-degree-of-freedom table; (3) Adjust the installation positions of the pitch axis autocollimator and the roll axis autocollimator so that their indications on the prism are in the middle of the measuring range.

[0103] The measurement result of the head end inertial group is recorded as R INT12GND , the measurement result of the tail inertia group is recorded as R INT22GND . Then the deformation of the device under test is:

[0104] R INT12INT2 =R Τ INT22GND R INT12GND (1)

[0105] It is known that the head-end inertial reference system and the autocollimator observation reference system are fixed on the stress-deformable plate, so there exists a fixed transformation matrix R OBS2INT1 It is also known that the tail end inertial reference system and the prism reference system are fixed on the deformation adjustment six-degree-of-freedom platform, so there exists a fixed transformation matrix R INT22PRI .

[0106] Then the following relationship always exists:

[0107] R INT22PRI R INT12INT2 R OBS2INT1 =R OBS2PRI (2)

[0108] In the case of dynamic deformation, the conversion relationship between the autocollimator observation reference system and the prism reference system is R OBS2PRI It can be obtained from the autocollimator under monitoring.

[0109] Select the current position as the dynamic deformation zero position, record the reading of the pitch axis autocollimator at this time, and record it as (θ PITCH0X ,θ PITCH0Y ); record the reading of the roll axis autocollimator at this time and record it as (θ ROLL0X ,θ ROLL0Y ). It is not a bad idea to assume that the autocollimator observation reference system coincides with the prism reference system at this time, then R OBS2PRI is the unit matrix. Measure and calculate the deformation of the head and tail inertia groups at this time, denoted as R INT12INT20 , then according to formula (2) we can get:

[0110]

[0111] Furthermore, under static conditions, the deformation adjustment six-degree-of-freedom stage is adjusted to produce an angle to change the deformation of the tail end of the deformation measuring device relative to the head end, and the angle monitoring value of the autocollimator will also change accordingly. Assuming that the deformation adjustment six-degree-of-freedom stage produces N different angles in total, the deformation obtained by the head and tail inertial groups during the i-th measurement process is recorded as R INT12INT2i The conversion relationship between the autocollimator observation reference system and the prism reference system is R OBS2PRIi , the matrix can be obtained from the autocollimator readings, record the readings of the pitch axis autocollimator during the i-th measurement process, and record it as (θ PITCHiX ,θ PITCHiY ); record the reading of the roll axis autocollimator at this time and record it as (θ ROLLiX ,θ ROLLiY ). At this time, the XPRI axis of the prism reference system in the autocollimator observation reference system is expressed as:

[0112]

[0113] The ZPRI axis of the prism reference system is expressed in the autocollimator observation reference system as follows:

[0114]

[0115] The YPRI axis of the prism reference system is expressed in the autocollimator observation reference system as follows:

[0116]

[0117] Then the conversion relationship between the autocollimator observation reference system and the prism reference system is R OBS2PRIi It can be expressed as:

[0118]

[0119] In this regard, by using the N acquisition results, combined with equation (2) and equation (3) at static zero position, the fixed transformation matrix R can be solved. OBS2INT1 and R INT22PRI .

[0120] After completing the static test, the deformation should also be adjusted to adjust the six-degree-of-freedom table back to the dynamic zero position.

[0121] 2. Dynamic test

[0122] Through static testing, the fixed transformation matrix R can be calibrated and obtained. OBS2INT1 and R INT22PRI On this basis, dynamic testing is carried out, and the specific steps are as follows.

[0123] (1) The front measuring end of the deformation measuring device under test, the rear measuring end of the deformation measuring device under test, the pitch axis autocollimator and the roll axis autocollimator are synchronized, and the device under test and the test equipment are required to mark the sampling timestamp in each measurement.

[0124] (2) Control the dynamically excited six-degree-of-freedom platform so that it sways according to the simulated sea and road conditions.

[0125] (3) Start continuous measurement of the front measuring end of the deformation measuring device, the rear measuring end of the deformation measuring device, the pitch axis autocollimator, and the roll axis autocollimator, and record the data.

[0126] (4) Data processing. The sampling sequences of the front end of the deformation measuring device, the rear end of the deformation measuring device, the pitch axis autocollimator and the roll axis autocollimator are {(x11, t11), (x12, t12), (x13, t13), …, (x1k, t1k), …}, {(x21, t21), (x22, t22), (x23, t23), …, (x2k, t2k), …}, {(x31, t31), (x32, t32), (x33, t33), …, (x3k, t3k), …}, {(x41, t41), (x42, t42), (x43, t43), …, (x4k, t4k), …}. Among the records with timestamps of the above four devices, the device with the lowest sampling frequency is selected, and its sampling time is used as the reference time point of the test. Let's assume that the pitch axis autocollimator has the lowest sampling frequency. Then for each sampling moment (x3k, t3k), find the sampling results of the remaining three devices at one moment after this sampling moment and three moments before this sampling moment. Taking the first measuring end of the measured deformation measuring device as an example, the recorded data are (x1(t-3), t1(t-3)), (x1(t-2), t1(t-2)), (x1(t-1), t1(t-1)), (x1t, t1t). Then the cubic spline curve can be used to obtain the fitting value (x1k, t3k) of the first measuring end of the measured deformation measuring device at time k. Other devices also use the same interpolation method to obtain their fitting values ​​at each sampling moment of the pitch axis autocollimator.

[0127] (5) After the sampling time is unified, the measured values ​​generated by the first measuring end and the last measuring end of the measured deformation measuring device can be used to obtain the deformation R of the measured device at the i-th moment. INT12INT2i According to equations (4) to (7), R can be calculated from the two autocollimators. OBS2PRIi , and then according to the fixed conversion relationship, the baseline value of the deformation at that moment can be obtained:

[0128]

[0129] (6) The deformation R measured by the device under test INT12INT2i And the reference value given by this device By expanding it on the three Euler angle components, the measurement error of the deformation can be obtained.

[0130] (7) By changing the material and dimensions of the stress-deformable plate, different dynamic deformation excitations can be generated to test the dynamic performance of the deformation measurement device.

[0131] The present invention does not elaborate on some of the well-known technologies that belong to those skilled in the art.

[0132] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in the description may be different and are not limited. Therefore, those skilled in the art in the field of the present invention may modify or replace the technical solutions recorded in the above embodiments; and these modifications and replacements do not deviate from the creative purpose and technical solutions of the present invention and should all fall within the protection scope of the present invention.

Claims

1. A deformation dynamic testing device based on a six-degree-of-freedom platform, characterized in that: include: A first six-degree-of-freedom platform (3) for generating dynamic excitation, wherein the upper surface of the first six-degree-of-freedom platform (3) comprises a first end portion, a second end portion, and a third end portion adjacent to both the first end portion and the second end portion; a stress-prone deformation plate (5) is disposed on the first end portion and the third end portion, and a second six-degree-of-freedom platform (4) is disposed on the second end portion; a first deformation measuring device (1) is rigidly connected to the stress-prone deformation plate (5), and the second end portion is rigidly connected to a second six-degree-of-freedom platform (4) having a size smaller than the first degree-of-freedom platform (3); and the second deformation measuring device (2) is rigidly connected to the second six-degree-of-freedom platform (4); a second autocollimator (7) parallel to the first deformation measuring device (1) is rigidly connected to the stress-sensitive deformation flat plate (5); a connecting line between the first deformation measuring device (1) and the second deformation measuring device (2) is determined, and the direction of the second autocollimator (7) is parallel to the connecting line direction; along a direction perpendicular to the connecting line, the first autocollimator (8) is deployed on the stress-sensitive deformation flat plate (5); the hexahedral prism (6) is rigidly connected to the second six-degree-of-freedom platform (4) through an L-shaped adapter fixture.

2. The device according to claim 1, characterized in that The first autocollimator (8) is used to provide a deformation component reference in the roll axis direction; the second autocollimator (7) is used to provide a deformation component reference in the pitch axis direction.

3. The device according to claim 2, characterized in that The deformation dynamic testing device based on the six-degree-of-freedom platform performs initial data calibration at the initial stage, including: The second six-degree-of-freedom platform (4) performs a static deformation zero position setting so that the first deformation measuring device (1) and the second deformation measuring device (2) produce relative deformations that meet preset requirements in a static state; the attitude indications of the first deformation measuring device (1) and the second deformation measuring device (2), as well as the indications of the second autocollimator (7) and the first autocollimator (8) are recorded, and the indications of the second autocollimator (7) and the first autocollimator (8) are used as static reference values; The first six-degree-of-freedom platform (3) performs motion simulation to generate disturbances of the stress-prone deformable plate (5) caused by forces in different postures under dynamic conditions, and records the posture indications of the first deformation measuring device (1) and the second deformation measuring device (2) and the indications of the first autocollimator (8) and the second autocollimator (7) while maintaining time synchronization between the first deformation measuring device (1) and the second deformation measuring device (2); and uses the indications of the first autocollimator (8) and the second autocollimator (7) as a true value reference for the dynamic deformation.

4. The device according to claim 3, characterized in that A reference coordinate system is established for the deformation dynamic testing device, wherein the reference coordinate system includes a first reference coordinate system O GND -X GND Y GND Z GND , the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 , the third reference coordinate system O INT2 -X INT2 Y INT2 Z INT2 , the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI , the fifth reference coordinate system O OBS -X OBS Y OBS Z OBS , where the first reference coordinate system O GND -X GND Y GND Z GND is the north-east inertial coordinate system of the test site where the deformation dynamic test device is located, that is, a right-handed system constructed by the local true north and the horizon of the test site; the second reference coordinate system O INT1 -X INT1 Y INT1 Z INT1 is the measurement reference system of the first deformation measuring device (1), X INT1 Axis, Y INT1 Axis and Z INT1 The axes correspond to the roll axis, azimuth axis and pitch axis of the first deformation measuring device (1) respectively; the third reference coordinate system O INT2 -X INT2 Y INT2 Z INT2 is the measurement reference system of the second deformation measuring device (2), X INT2 Axis, Y INT2 Axis and Z INT2 The axes correspond to the roll axis, azimuth axis and pitch axis of the second deformation measuring device (2) respectively; the fourth reference coordinate system O PRI -X PRI Y PRI Z PRI The three mutually orthogonal normal lines of the hexahedral prism (6) are used as coordinate axes; the fifth reference coordinate system O OBS -X OBS Y OBS Z OBS It is a reference coordinate system for representing the observation of the hexahedral prism (6) by two autocollimators, and the initial directions of the coordinate axes thereof are the same as those of the second reference coordinate system.

5. The device according to any one of claims 1 to 4, characterized in that The dynamic excitation generated by the first six-degree-of-freedom platform (3) simulates the mechanical excitation under sea conditions or road conditions, thereby generating a dynamic deformation amount.

6. A method for dynamic deformation testing based on a six-degree-of-freedom platform, based on the dynamic deformation testing device based on a six-degree-of-freedom platform as claimed in any one of claims 1 to 4, characterized in that: include: Step S31: The second six-degree-of-freedom platform (4) generates the relative deformation R of the first deformation measuring device (1) and the second deformation measuring device (2) in a static state. INT12INT20 ; Determine the reading (θ) of the first autocollimator (8) ROLL0X ,θ ROLL0Y ) is its zero position offset value in azimuth and elevation, and the reading (θ PITCH0X ,θ PITCH0Y ) is the zero offset value in azimuth and elevation, and there is a static measurement relationship Among them, R INT22PRI is the transformation matrix between the third reference coordinate system and the fourth reference coordinate system, R OBS2INT1 is the transformation matrix between the second reference coordinate system and the fifth reference coordinate system; Step S32: Obtain the static zero position measurement result R of the first deformation measuring device (1) INT12GND0 , the static zero position measurement result R of the second deformation measuring device (2) INT22GND0 , then the following relationship exists: R INT12INT20 =R Τ INT22GND0 ·R INT12GND0 ; Step S33: Under static conditions, the second six-degree-of-freedom platform (4) is adjusted to produce different tilt angles. The following operation is performed once for each tilt angle, and an i value is updated each time the operation is performed: After the adjustment, the relative posture conversion relationship between the first deformation measuring device (1) and the second deformation measuring device (2) is obtained, which is recorded as R INT12INT2i Based on the readings of the first autocollimator (8) and the second autocollimator (7), the conversion relationship R between the fourth reference coordinate system and the fifth reference coordinate system is obtained. OBS2PRIi ; Get the reading of the second autocollimator (7) at this time, recorded as (θ PITCHiX ,θ PITCHiY ), where θ PITCHiX is the deflection angle of the elevation axis of the hexahedral prism (6) in the azimuth direction, θ PITCHiY is the deflection angle of the pitch axis of the hexagonal prism (6) in the pitch direction; the reading of the first autocollimator (8) at this time is obtained and recorded as (θ ROLLiX ,θ ROLLiY ), where θ ROLLiX is the deflection angle of the roll axis of the hexahedral prism (6) in the azimuth direction, θ ROLLiY is the deflection angle of the roll axis of the hexahedral prism (6) in the pitch direction; at this time, the X PRI The axis is expressed in the fifth reference coordinate system as: The fourth reference coordinate system X PRI The axis is expressed in the fifth reference coordinate system as: Calculate the Y of the fourth reference coordinate system PRI Representation of the axis in the fifth reference coordinate system: Then the transformation relationship R between the fifth reference coordinate system and the fourth reference coordinate system is OBS2PRIi It is expressed as: Step S34: Based on all R OBS2PRIi , use arithmetic mean and orthogonalization to determine R OBS2PRI Step S35: Calculate the fixed transformation matrix R OBS2INT1 and R INT22PRI ,include: Step S351: Determine the deformation of the upper surface of the stress-deformable plate (5) monitored by the first deformation measuring device (1) and the upper surface of the second six-degree-of-freedom platform (4) monitored by the second deformation measuring device (2): R INT12INT2 =R Τ INT22GND R INT12GND ; Step S352: Solve the fixed transformation matrix R based on the following formula OBS2INT1 and R INT22PRI : R INT22PRI R INT12INT2 R OBS2INT1 =R OBS2PRI Step S36: the angle maintained by the first six-degree-of-freedom platform (3) during the dynamic test is used as a reference position for deformation measurement, the first six-degree-of-freedom platform (3) performs motion simulation to generate different postures so as to generate deformation disturbances on the stress-prone deformable plate (5), and the posture data of the first deformation measuring device (1) and the second deformation measuring device (2) at the same time sampling point are obtained while maintaining the time synchronization of the first deformation measuring device (1) and the second deformation measuring device (2), and the indications of the first autocollimator (8) and the second autocollimator (7); based on the corresponding sampling point data, the outputs of the first deformation measuring device (1), the second deformation measuring device (2), the first autocollimator (8), and the second autocollimator (7) are respectively fitted to obtain the output curve of the first deformation measuring device (1), the output curve of the second deformation measuring device (2), the output curve of the first autocollimator (8), and the output curve of the second autocollimator (7); Step S37: Based on the output curve of the first deformation measuring device (1) and the output curve of the second deformation measuring device (2), the deformation amount R between the first deformation measuring device (1) and the second deformation measuring device (2) at the jth moment is obtained. INT12INT2j , based on R OBS2PRI , determine R OBS2PRIj ;According to the fixed conversion relationship, the base value of the deformation at that moment is obtained Step S38: R INT12INT2j and benchmark value Expanding on the three Euler angle components, we get the measurement error; Step S39: Based on the measurement error and its decomposition in different axis directions, the dynamic performance of the deformation dynamic testing device based on the six-degree-of-freedom table is determined.

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