CN110542430A - large dynamic performance testing device and method for inertial measurement unit - Google Patents

Abstract

A large dynamic performance testing device and method for an inertia measurement unit comprises the following steps: force bearing structure, pressure bearing, angle dial, angle pointer, spacer pin, rigid swing arm, mounting panel. The bearing structure comprises a bottom plate, a support column and a cantilever beam which are connected in sequence. The supporting column is used for changing the distance between the cantilever beam and the bottom plate; the mounting plate is fixedly connected with one end of the rigid swing arm, and the other end of the rigid swing arm is connected with a cantilever beam of the bearing structure through a pressure bearing; an angle dial is arranged at the connecting position of the rigid swing arm and the pressure bearing, an angle pointer is fixedly connected with the rigid swing arm, and the angle dial and the angle pointer are used for measuring the rotation angle between the rigid swing arm and the pressure bearing; the rigid swing arm is used for changing the distance between the mounting plate and the cantilever beam; the cantilever beam is provided with a limit pin for limiting the swing of the rigid swing arm, and the mounting plate is used for mounting the inertia measurement unit to be measured. The invention can be used for verifying the product performance of the inertia measurement unit under the large dynamic condition that the angular velocity reaches more than 1000 DEG/s and the acceleration reaches more than 5 g.

Description

large dynamic performance testing device and method for inertial measurement unit

Technical Field

The invention relates to a large dynamic performance testing device and method for an inertia measurement unit, and belongs to the technical field of performance verification of the inertia measurement unit.

background

An Inertial Measurement Unit (IMU) is a key sensor in an inertial navigation system, generally consists of 3 gyroscopes and 3 accelerometers, and is widely applied in various fields such as aerospace and the like. In some special cases, the inertia measurement unit product needs to measure and navigate under a large dynamic working condition, such as a working condition with an angular velocity of more than 1000 degrees/s. Therefore, the performance of the inertia measurement unit product needs to be fully verified in a ground laboratory before the product is put into use formally.

The performance of the inertial measurement unit product is generally evaluated using a rotary table. For example, patent CN201310675186.6 discloses a dynamic testing method for an inertial navigation system, in the invention, a three-axis turntable is used to perform performance verification on the inertial navigation system, but the general turntable has limited rotation capability, cannot meet the performance testing requirement of an inertial measurement unit under a large dynamic working condition, and is expensive.

in addition to the turntable, patent CN201320777425.4 discloses an inertial navigation technology simulation test system, which includes a vehicle, a shelter, an alignment simulation device, a vehicle-mounted test system, a GPS forwarding system and a power supply system, and the invention provides a real operating environment for the inertial navigation to be tested by using the advancing of the vehicle and the rotation of the vehicle-mounted turntable, but generally cannot provide a large enough dynamic environment, and the test cost of the invention is high. The patent CN201220006096.9 discloses a gyroscope testing device, which includes a fulcrum, a power arm, a pendulum, an optimal sample of a gyroscope integrated circuit, and a gyroscope integrated circuit to be tested, however, the invention designs an active simple pendulum device, which is relatively complex in design, high in development cost, and does not give applicability in a large dynamic environment.

disclosure of Invention

the technical problem solved by the invention is as follows: the device is simple and reliable, has low cost, is simple and easy to operate, can fully verify the measurement performance and the navigation performance of the inertia measurement unit under the large dynamic working condition that the angular velocity reaches more than 1000 DEG/s and the acceleration reaches more than 5g, and provides reliable guarantee for the use of the inertia measurement unit.

the technical scheme of the invention is as follows:

A large dynamic performance testing device for an inertial measurement unit comprises: the device comprises a force bearing structure, a pressure bearing, an angle dial, an angle pointer, a limiting pin, a rigid swing arm and a mounting plate; the force bearing structure comprises a bottom plate, a support pillar and a cantilever beam; the bottom plate, the support pillar and the cantilever beam are sequentially connected, and the support pillar is used for changing the distance between the cantilever beam and the bottom plate; the mounting plate is fixedly connected with one end of the rigid swing arm, and the other end of the rigid swing arm is connected with a cantilever beam of the bearing structure through a pressure bearing; an angle dial is arranged at the connecting position of the rigid swing arm and the pressure bearing, an angle pointer is fixedly connected with the rigid swing arm, and the angle dial and the angle pointer are used for measuring the rotation angle between the rigid swing arm and the pressure bearing; the rigid swing arm is used for changing the distance between the mounting plate and the cantilever beam; the cantilever beam is provided with a limiting pin for limiting the swing of the rigid swing arm, and the limiting pin can move on a slide way of the cantilever beam; the mounting plate is used for mounting an inertia measurement unit to be measured.

a method for testing the large dynamic performance of an inertia measurement unit by using the large dynamic performance testing device of the inertia measurement unit comprises the following steps:

1) fixing an inertia measurement unit to be tested on a mounting plate, enabling a rigid swing arm to swing around a pressure bearing in a reciprocating manner in a vertical plane, wherein the value range of the swing angle of the swing is not more than 10 degrees, obtaining the swing time TN of the rigid swing arm swinging through an initial static position for N times continuously, wherein N is a positive integer and is not less than 10, and determining a structural characteristic parameter Kd evice of the testing device according to N and TN;

2) In a static state, the rigid swing arm vertically droops to be positioned at an initial position, and angular velocity and acceleration data output by the inertia measurement unit to be measured are collected;

3) Lifting the free end of the rigid swing arm to enable the included angle between the rigid swing arm and the vertical surface to be equal to a set initial swing angle theta 0, releasing the rigid swing arm to enable the rigid swing arm to freely fall and swing around the rotating shaft, and collecting angular velocity and acceleration data output by the inertia measurement unit to be measured; the value range of theta 0 is 0-180 degrees;

4) After the rigid swing arm returns to a static state, collecting angular velocity and acceleration data output by an inertia measurement unit to be measured;

5) determining real-time angular velocity omega calculated and real-time acceleration acellulate of an inertia measurement unit in the free falling process of the rigid swing arm according to the structural characteristic parameter Kdovice obtained in the step 1) and the initial swing angle theta 0 set in the step 3);

6) judging whether the measurement performance of the inertia measurement unit to be measured under the condition of large dynamic meets the use requirement or not according to the real-time angular velocity omega calculated and the real-time acceleration accelerate determined in the step 5) and the angular velocity and acceleration data output by the inertia measurement unit to be measured and acquired in the step 3);

7) determining a navigation attitude error, a navigation position error and a navigation speed error of the inertial measurement unit to be measured according to the angular velocity and acceleration data output by the inertial measurement unit to be measured acquired in the steps 2), 3) and 4);

8) And judging whether the navigation performance of the inertial measurement unit to be measured under the large dynamic condition meets the use requirement or not according to the navigation attitude error, the navigation position error and the navigation speed error determined in the step 7).

the method for determining the structural characteristic parameter Kdovice of the testing device in the step 1) specifically comprises the following steps:

the step 5) is a method for determining the real-time angular velocity omega calculated and the real-time acceleration accelrate of the inertia measurement unit in the free falling process of the rigid swing arm, and specifically comprises the following steps:

wherein, theta is that real-time demonstration on the angle calibrated scale rigid swing arm with turned angle between the pressure bearing, g are acceleration of gravity, L be by the barycenter of the assembly that mounting panel, cantilever beam and the inertia measuring unit combination that awaits measuring formed arrives the distance of pressure bearing axis.

The step 6) is a method for judging whether the measurement performance of the inertia measurement unit to be measured meets the use requirement under the condition of large dynamic, and the method specifically comprises the following steps:

When delta omega is less than or equal to { delta omega } index and delta a is less than or equal to { delta a } index, judging that the large dynamic measurement performance of the inertial measurement unit to be measured meets the use requirement;

When delta omega > { delta omega } index or delta a > { delta a } index exists, the large dynamic measurement performance of the inertia measurement unit to be measured is judged not to meet the use requirement;

δω＝|ω-ω|，

δa＝|a-a|，

the method comprises the following steps of measuring the angular speed and the acceleration of an inertial measurement unit to be measured, wherein omega measure and parameter are the angular speed and the acceleration actually output by the inertial measurement unit to be measured, delta omega index is the angular speed index of the inertial measurement unit to be measured, and delta a index is the acceleration index of the inertial measurement unit to be measured.

the step 8) is a method for judging whether the navigation performance of the inertial measurement unit to be measured meets the use requirement under the condition of large dynamic, and specifically comprises the following steps:

when the { delta phi } navigation is less than or equal to the { delta phi } index, the { delta R } navigation is less than or equal to the { delta R } index, and the { delta V } navigation is less than or equal to the { delta V } index, determining that the large dynamic navigation performance of the inertial measurement unit to be measured meets the use requirement;

When the { delta phi } navigation > { delta phi } index or the { delta R } navigation > { delta R } index or the { delta V } navigation > { delta V } index exists, determining that the large dynamic navigation performance of the inertial measurement unit to be measured cannot meet the use requirement;

Wherein, { δ Φ } navigation is a navigation attitude error, { δ R } navigation is a navigation position error, { δ V } navigation is a navigation speed error, { δ Φ } index is a navigation attitude error index of the inertial measurement unit under test, { δ R } index is a navigation position error index of the inertial measurement unit under test, and { δ V } index is a navigation speed error index of the inertial measurement unit under test.

compared with the prior art, the invention has the beneficial effects that:

1) The device consists of passive components, is simple and reliable, has low manufacturing cost, strong engineering implementation and easy operation, and can fully verify the performance of the inertia measurement unit by using the testing device and a corresponding testing method;

2) The invention generates different angular velocities by adjusting the initial swing angle and the length of the swing arm, the larger the initial swing angle is, the shorter the swing length is, the larger the angular velocity is, various dynamic working conditions meeting the test conditions can be obtained, the angular velocity value range of the test working conditions is from 0 degree/s to more than 1000 degrees/s, the acceleration value range is from 0g to more than 5g, and g is the gravity acceleration;

3) the invention provides a method for theoretically calculating real-time angular velocity and acceleration, and the method is used for verifying the measurement performance of an inertia measurement unit by comparing the real-time angular velocity and the real-time acceleration measured by the inertia measurement unit, so that the limit that the measurement performance and the saturation characteristic of a plurality of devices cannot be checked under a large dynamic working condition due to insufficient measurement range is broken through;

4) the invention provides a test method for verifying the navigation performance of an inertial measurement unit, which is simple to operate, has real and effective test results, and can perform reverse verification on different navigation algorithms.

drawings

FIG. 1 is a schematic view of the apparatus of the present invention;

FIG. 2 is a schematic view of the swing joint structure of the device of the present invention;

FIG. 3 is a schematic view of the swing joint structure of the device of the present invention;

FIG. 4 is a flow chart of the method of the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and the detailed description.

an inertia measurement unit large dynamic performance testing device, as shown in fig. 1, 2 and 3, comprises: force bearing structure 1, pressure bearing 2, angle scale 3, angle pointer 4, spacer pin 5, rigid swing arm 6, mounting panel 7. The force bearing mechanism 1 provides a firm and stable motion environment and consists of a bottom plate 11, a support column 12 and a cantilever beam 13. The base plate 11, the supporting columns 12 and the cantilever beams 13 are sequentially connected, and the distance between the cantilever beams 13 and the base plate 11 can be changed through the telescopic supporting columns 12, so that the test requirements are met. The mounting panel 7 fixed connection rigidity swing arm 6's one end, rigidity swing arm 6's the other end passes through pressure bearing 2 and connects the cantilever beam 13 of bearing structure 1. An angle dial 3 is arranged at the connecting position of the rigid swing arm 6 and the pressure bearing 2, an angle pointer 4 is fixedly connected with the rigid swing arm 6, and the angle dial 3 and the angle pointer 4 are used for measuring the rotation angle between the rigid swing arm 6 and the pressure bearing 2; the rigid swing arm 6 is used to vary the distance between the mounting plate 7 and the cantilever beam 13. And a limiting pin 5 for limiting the swing of the rigid swing arm 6 is arranged on the cantilever beam 13, and the limiting pin 5 can move on a slide way of the cantilever beam. The mounting plate 7 is used for mounting an inertia measurement unit product to be measured.

a method for testing the large dynamic performance of the inertial measurement unit by using the large dynamic performance testing device of the inertial measurement unit is shown in FIG. 4, and comprises the following steps:

1) fixing an inertia measurement unit to be tested on a mounting plate 7, enabling a rigid swing arm 6 to swing around a pressure bearing 2 in a reciprocating manner in a vertical plane, wherein the value range of the swing angle of the swing is not more than 10 degrees, obtaining the swing time TN of the rigid swing arm 6 continuously swinging for N times through a midpoint position, namely an initial rest position, wherein N is a positive integer and is not less than 10, and determining a structural characteristic parameter Kd evice of the testing device according to N and TN, specifically:

2) in a static state, the rigid swing arm 6 vertically droops to be positioned at an initial position, and angular velocity and acceleration data output by the inertia measurement unit to be measured are collected;

3) lifting the free end of the rigid swing arm 6 to enable the included angle between the rigid swing arm 6 and the vertical surface to be equal to a set initial swing angle theta 0, releasing the rigid swing arm 6 to enable the rigid swing arm 6 to freely fall and swing around the rotating shaft, and collecting angular velocity and acceleration data output by the inertia measurement unit to be measured; the value range of theta 0 is 0-180 degrees;

4) when the rigid swing arm 6 swings to a recovery static state under the action of external force or freely, collecting angular velocity and acceleration data output by an inertia measurement unit to be measured;

5) determining a real-time angular velocity omega calculated and a real-time acceleration acolculate of an inertia measurement unit in the free falling process of the rigid swing arm 6 according to the structural characteristic parameter Kduevice obtained in the step 1) and the initial swing angle theta 0 set in the step 3), and specifically:

Wherein, theta is that real-time demonstration on the angle dial 3 rigid swing arm 6 with turned angle between the pressure bearing 2, g are acceleration of gravity, L be by the barycenter of the assembly that mounting panel (7), cantilever beam (13) and the inertia measuring unit combination that awaits measuring formed arrives the distance of pressure bearing (2) axis, 6 free fall of rigid swing arm are promptly around the equivalent barycenter of the equivalent simple pendulum motion of pivot swing.

6) Judging whether the measurement performance of the inertia measurement unit to be measured under the condition of large dynamic meets the use requirement or not according to the real-time angular velocity omega calculated and the real-time acceleration acalculate determined in the step 5) and the angular velocity and acceleration data output by the inertia measurement unit to be measured and acquired in the step 3), wherein the method specifically comprises the following steps:

when delta omega is less than or equal to { delta omega } index and delta a is less than or equal to { delta a } index, judging that the large dynamic measurement performance of the inertial measurement unit to be measured meets the use requirement;

When delta omega > { delta omega } index or delta a > { delta a } index exists, the large dynamic measurement performance of the inertia measurement unit to be measured is judged not to meet the use requirement;

δω＝|ω-ω|，

δa＝|a-a|，

The method comprises the following steps of measuring the angular speed and the acceleration of an inertial measurement unit to be measured, wherein omega measure and parameter are the angular speed and the acceleration actually output by the inertial measurement unit to be measured, delta omega index is the angular speed index of the inertial measurement unit to be measured, and delta a index is the acceleration index of the inertial measurement unit to be measured.

7) determining a navigation attitude error, a navigation position error and a navigation speed error of the inertial measurement unit to be measured according to the angular velocity and acceleration data output by the inertial measurement unit to be measured, which are acquired in the steps 2), 3) and 4), and a navigation calculation method, wherein the navigation attitude error, the navigation position error and the navigation speed error are specifically as follows:

the method comprises the following steps of (1) obtaining angular velocity and acceleration data output by the inertial measurement unit in step 2) by adopting a dual-vector method, wherein Qinitial, Rinitial and Vinitial are an initial attitude quaternion, an initial position and an initial speed of the inertial measurement unit, Qfinal, Rfinal and Vfinal are an end attitude quaternion, an end position and an end speed of the inertial measurement unit, obtaining angular velocity and acceleration data output by the inertial measurement unit in step 4) by adopting the dual-vector method, Tnavigations are navigation time duration, F (-) is a navigation algorithm, the algorithm is not particularly limited, delta phi } navigation is a navigation attitude error obtained by calculation, { delta R } navigation is a navigation position error obtained by calculation, and { delta V } navigation is a navigation speed error obtained by calculation.

8) judging whether the navigation performance of the inertial measurement unit to be measured under the condition of large dynamic meets the use requirement or not according to the navigation attitude error, the navigation position error and the navigation speed error determined in the step 7), which specifically comprises the following steps:

when the { delta phi } navigation is less than or equal to the { delta phi } index, the { delta R } navigation is less than or equal to the { delta R } index, and the { delta V } navigation is less than or equal to the { delta V } index, determining that the large dynamic navigation performance of the inertial measurement unit meets the use requirement;

When the { delta phi } navigation is > (delta phi } index or the { delta R } navigation is > (delta R } index or the { delta V } navigation is > (delta V } index), judging that the large dynamic navigation performance of the inertial measurement unit does not meet the use requirement;

The method comprises the steps of measuring the navigation position error of an inertial measurement unit to be measured by a { delta phi } index, measuring the navigation position error of the inertial measurement unit to be measured by a { delta R } index, and measuring the navigation speed error of the inertial measurement unit to be measured by a { delta V } index.

examples

N is 10, by adjusting the length L of the rigid swing arm 6 to 0.15m, TN is 6s, the initial swing angle θ 0 is 180 °, and the structural characteristic parameter Kdevice is 109.66, when the swing reaches the lowest point in the first period, i.e., θ is 0 °, the maximum angular velocity value ω calculate reaches 1200 °/s, and the maximum acceleration value acalculate reaches 7.7 g.

Those skilled in the art will appreciate that the details of the invention not described in detail in the specification are within the skill of those skilled in the art.

Claims (6)

1. The large dynamic performance testing device of the inertial measurement unit is characterized by comprising: the device comprises a force bearing structure (1), a pressure bearing (2), an angle scale disc (3), an angle pointer (4), a limiting pin (5), a rigid swing arm (6) and a mounting plate (7);

the bearing structure (1) comprises a bottom plate (11), a supporting column (12) and a cantilever beam (13);

the base plate (11), the supporting column (12) and the cantilever beam (13) are sequentially connected, and the supporting column (12) is used for changing the distance between the cantilever beam (13) and the base plate (11);

The mounting plate (7) is fixedly connected with one end of the rigid swing arm (6), and the other end of the rigid swing arm (6) is connected with a cantilever beam (13) of the bearing structure (1) through a pressure bearing (2);

an angle dial (3) is arranged at the connecting position of the rigid swing arm (6) and the pressure bearing (2), an angle pointer (4) is fixedly connected with the rigid swing arm (6), and the angle dial (3) and the angle pointer (4) are used for measuring the rotating angle between the rigid swing arm (6) and the pressure bearing (2);

the rigid swing arm (6) is used for changing the distance between the mounting plate (7) and the cantilever beam (13);

the cantilever beam (13) is provided with a limiting pin (5) for limiting the swing of the rigid swing arm (6), and the limiting pin (5) can move on a slide way of the limiting pin;

The mounting plate (7) is used for mounting an inertia measuring unit to be measured.

2. a method for testing the large dynamic performance of an inertial measurement unit by using the large dynamic performance testing device of the inertial measurement unit according to claim 1, which comprises the following steps:

1) Fixing an inertia measurement unit to be tested on a mounting plate (7), enabling a rigid swing arm (6) to swing around a pressure bearing (2) in a reciprocating manner in a vertical plane, wherein the swing angle value range of the swing is not more than 10 degrees, obtaining the swing time TN of the rigid swing arm (6) swinging past an initial rest position for N times continuously, wherein N is a positive integer and is not less than 10, and determining a structural characteristic parameter Kjevice of the testing device according to N and TN;

2) in a static state, the rigid swing arm (6) vertically droops to be positioned at an initial position, and angular velocity and acceleration data output by the inertia measurement unit to be measured are collected;

3) Lifting the free end of the rigid swing arm (6), enabling the included angle between the rigid swing arm (6) and the vertical surface to be equal to a set initial swing angle theta 0, releasing the rigid swing arm (6), enabling the rigid swing arm (6) to freely fall and swing around the rotating shaft, and collecting angular velocity and acceleration data output by the inertial measurement unit to be measured; the value range of theta 0 is 0-180 degrees;

4) when the rigid swing arm (6) returns to a static state, acquiring angular velocity and acceleration data output by the inertia measurement unit to be measured;

5) Determining real-time angular velocity omega calculated and real-time acceleration acolculate of an inertia measuring unit in the free falling process of the rigid swing arm (6) according to the structural characteristic parameter Kdovice obtained in the step 1) and the initial swing angle theta 0 set in the step 3);

6) Judging whether the measurement performance of the inertia measurement unit to be measured under the condition of large dynamic meets the use requirement or not according to the real-time angular velocity omega calculated and the real-time acceleration accelerate determined in the step 5) and the angular velocity and acceleration data output by the inertia measurement unit to be measured and acquired in the step 3);

7) determining a navigation attitude error, a navigation position error and a navigation speed error of the inertial measurement unit to be measured according to the angular velocity and acceleration data output by the inertial measurement unit to be measured acquired in the steps 2), 3) and 4);

8) and judging whether the navigation performance of the inertial measurement unit to be measured under the large dynamic condition meets the use requirement or not according to the navigation attitude error, the navigation position error and the navigation speed error determined in the step 7).

3. the method for testing the large dynamic performance of the inertial measurement unit according to claim 2, wherein the step 1) is a method for determining a structural characteristic parameter Kdevice of the testing device, and specifically comprises:

4. the method for testing the large dynamic performance of the inertial measurement unit according to claim 3, wherein the step 5) is a method for determining the real-time angular velocity ω calculate and the real-time acceleration acalculate of the inertial measurement unit during the free fall of the rigid swing arm (6), and specifically comprises the following steps:

Wherein, theta is that real-time demonstration is gone up in angle dial (3) rigidity swing arm (6) with turned angle between pressure bearing (2), g are acceleration of gravity, L be by the barycenter of the assembly that mounting panel (7), cantilever beam (13) and the inertia measuring unit combination that awaits measuring formed arrives the distance of pressure bearing (2) axis.

5. the method for testing the large dynamic performance of the inertia measurement unit according to claims 2 to 4, wherein the step 6) is a method for determining whether the measurement performance of the inertia measurement unit to be tested under the large dynamic condition meets the use requirement, and specifically comprises the following steps:

when delta omega is less than or equal to { delta omega } index and delta a is less than or equal to { delta a } index, judging that the large dynamic measurement performance of the inertial measurement unit to be measured meets the use requirement;

when delta omega > { delta omega } index or delta a > { delta a } index exists, the large dynamic measurement performance of the inertia measurement unit to be measured is judged not to meet the use requirement;

δω＝|ω-ω|，

δa＝|a-a|，

the method comprises the following steps of measuring the angular speed and the acceleration of an inertial measurement unit to be measured, wherein omega measure and parameter are the angular speed and the acceleration actually output by the inertial measurement unit to be measured, delta omega index is the angular speed index of the inertial measurement unit to be measured, and delta a index is the acceleration index of the inertial measurement unit to be measured.

6. the method for testing the large dynamic performance of the inertial measurement unit according to claim 5, wherein the step 8) is a method for determining whether the navigation performance of the inertial measurement unit under test under the large dynamic condition meets the use requirement, and specifically comprises the following steps:

When the { delta phi } navigation is less than or equal to the { delta phi } index, the { delta R } navigation is less than or equal to the { delta R } index, and the { delta V } navigation is less than or equal to the { delta V } index, determining that the large dynamic navigation performance of the inertial measurement unit to be measured meets the use requirement;

when the { delta phi } navigation > { delta phi } index or the { delta R } navigation > { delta R } index or the { delta V } navigation > { delta V } index exists, determining that the large dynamic navigation performance of the inertial measurement unit to be measured cannot meet the use requirement;

wherein, { δ Φ } navigation is a navigation attitude error, { δ R } navigation is a navigation position error, { δ V } navigation is a navigation speed error, { δ Φ } index is a navigation attitude error index of the inertial measurement unit under test, { δ R } index is a navigation position error index of the inertial measurement unit under test, and { δ V } index is a navigation speed error index of the inertial measurement unit under test.