CN113916219B - Inertial measurement system error separation method based on centrifugal machine excitation - Google Patents
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Abstract
The invention discloses an inertial measurement system error separation method based on centrifugal machine large overload excitation, which utilizes the characteristic that the length of a centrifugal machine lever arm is unchanged, and combines the rotation angle of the centrifugal machine lever arm in the rotation process to obtain the motion trail of an inertial measurement system arranged on the lever arm; in addition, the visual acceleration of the inertial measurement system is subjected to navigation calculation to obtain a motion track with an error, wherein the error is mainly caused by the measurement errors of the gyroscope and the accelerometer; by comparing the difference values of the two tracks, the least square method can be adopted to process each error coefficient of the inertial measurement system, and the accuracy of inertial navigation is improved through error compensation.
Description
Technical Field
The invention relates to an inertial measurement system error separation method based on centrifugal machine excitation, in particular to an error calibration and compensation method for a dynamic installation deviation matrix, which is mainly used in the field of aviation and aerospace of high-precision inertial navigation.
Background
Inertial navigation is widely applied to the fields of missiles, airplanes, ships, weapons and the like, and is mainly used for determining the position, speed and attitude information of a carrier relative to a navigation system in real time. In the process of realizing the navigation function, the accuracy of the inertial device (comprising a gyroscope and an accelerometer) directly determines the accuracy of the gesture, the position and the speed. In order to achieve high-precision navigation, the precision of the accelerometer must be improved in terms of hardware, but due to the fundamental subjects such as materials, processes and the like, it is difficult to greatly improve the precision of the inertial device in a short period of time. The error compensation method can obviously improve the use precision of the inertial device in a short period.
The precondition for error compensation is that the error coefficient is calibrated. At present, the multi-position rolling test based on the gravity field can only separate low-order error items such as zero offset and scale factors, and the confidence of the separated high-order error items such as secondary items, odd secondary items, cross-coupling items and the like is lower. For this reason, developing a high-order error term separation method based on centrifuge large overload excitation is a key technology.
When the inertial device error coefficient is separated by a centrifuge, a centrifuge having high accuracy is required. In the data disclosed at present, the acceleration of the centrifugal machine is used as the reference for error separation of the inertial device. The basic principle of the centrifugal machine is a single-shaft speed turntable, and centripetal acceleration can be generated in the rotation process of a lever arm of the centrifugal machine. When a constant centripetal acceleration is required, the rotational speed of the centrifuge is required to be very stable. For example, a gyro accelerometer is used as a measured object, and the linearity of the gyro accelerometer can reach 1×10 -5, so that the stability of the rotation speed of the centrifugal machine is required to be better than that of the centrifugal machine of 3×10 -6. However, in the practical application process, the rotational speed stability of the developed centrifugal machine can only reach 1 multiplied by 10 -4, and the requirement of error separation of an inertial device cannot be met. Therefore, how to effectively isolate the error of the high precision inertial device on a relatively low precision centrifuge is a key technique.
Therefore, an error separation method of an inertial measurement system based on centrifugal machine large overload excitation needs to be studied to improve the use precision of an inertial device through error compensation, and further improve the precision of inertial navigation.
Disclosure of Invention
The technical solution of the invention is as follows: the error separation method of the inertial measurement system based on centrifugal machine excitation is provided, various error coefficients of the inertial measurement system are separated, and the accuracy of inertial navigation is improved through error compensation.
The technical scheme of the invention is as follows: an inertial measurement system error separation method based on centrifuge excitation, the method comprising the steps of:
S1, establishing an inertial measurement system error separation test system: one end of one side of the centrifugal machine lever arm is provided with a reversing platform, the inertia measuring system is arranged on the reversing platform, the other side is provided with a counterweight for balancing the mass sum of the reversing platform and the inertia measuring system, and the rotating speed of the reversing platform relative to the centrifugal machine lever arm is higher than that of the centrifugal machine lever arm when the reversing platform rotates Rotational speed of the centrifuge lever arm relative to groundIs of opposite numbers, i.e Wherein ω is the rotational speed of the centrifuge lever arm relative to the centrifuge base (1);
S2, performing inertial measurement system error separation test: the centrifugal machine lever arm is driven to rotate around the base at a high speed to form centripetal acceleration, the centripetal acceleration is the excitation of an inertial measurement system arranged on the centrifugal machine lever arm, and the motion trail of the inertial measurement system arranged on the centrifugal machine lever arm is obtained by combining the rotation angle of the centrifugal machine lever arm in the rotation process by utilizing the characteristic of unchanged length of the centrifugal machine lever arm and is recorded as a reference motion trail; navigation and calculation are carried out on the visual acceleration of the inertial measurement system, a motion track with errors is obtained, and the motion track is recorded as a measurement motion track; comparing the difference value of the measured motion track and the reference motion track to obtain a position error sequence value of the inertial measurement system;
S3, substituting the position error sequence value of the inertial measurement system into an inertial navigation position error model, and separating out each error coefficient of the inertial measurement system by adopting a least square method;
s4, correcting the inertial measurement system error which participates in the navigation calculation by utilizing the determined inertial measurement system error coefficient, and further realizing the compensation of the inertial measurement system navigation calculation.
The base coordinate system of the centrifugal machine is overlapped with the northeast geographic coordinate system (Ox eyeze), wherein Ox e refers to east, oy e refers to north, oz e refers to the day, and the three meet the right-hand coordinate system;
The lever arm coordinate system of the centrifugal machine is Ox pypzp, wherein Ox p is coincided with the lever arm and points outwards, oy p is perpendicular to the lever arm and is positioned in the horizontal plane, oz p refers to days, and the three meet the right-hand coordinate system;
The coordinate system of the inversion platform is Ox qyqzq, wherein Ox q and Oy q are in a horizontal plane, oz q refers to days, and the three meet the right-hand coordinate system;
The inertial measurement system coordinate system is Ox bybzb, which is the same as the coordinate axis of the inversion platform coordinate system Ox qyqzq.
The specific implementation of the step S2 is as follows:
S2.1, at an initial time t 0, completing initial alignment of an inertial measurement system so that an inertial navigation coordinate system is physically coincident with a northeast ground coordinate system Ox eyeze;
S2.2, according to the measured rotation angle of the centrifuge lever arm relative to the base at the initial time t 0 Calculating the initial value (x ew,0,yew,0,yew,0) of the position of the inertial measurement system relative to the northeast ground coordinate system Ox eyeze at the initial time t 0 in the reference motion track, setting the initial value of the speed of the inertial measurement system relative to the northeast ground coordinate system Ox eyeze at the initial time t 0 in the reference motion track as 0, initializing k as 1 when the next calculation period comes, and then sequentially executing the steps S3.2-S3.5;
S3.2, according to the measured angle value when the centrifuge lever arm rotates relative to the base Calculating the position of the inertial measurement system at the current time t k relative to the northeast sky ground coordinate system (Ox eyeze);
S3.3, measuring the angular velocity according to a gyroscope in the inertial measurement system The accelerometer is combined to measure and obtain the apparent accelerationNavigation solution is carried out to obtain the position at the current time t k
S3.4, calculating corresponding track point position errors in the reference motion track and the measurement motion track:
S3.5, when the next calculation period arrives, returning k=k+1 to the step S3.2 to execute the steps S3.2-S3.5 again until reaching the end time t N, and entering the step S3.6;
S3.6, summarizing the position errors of corresponding track points in the reference motion track and the measurement motion track to obtain a position error sequence value Y:
In the steps (3.1) and (3.2):
the calculation formula of the initial value (x ew,k,yew,k,yew,k) of the position of the inertial measurement system relative to the northeast sky and ground coordinate system at the initial time t k in the reference motion trail is as follows:
wherein R is half of the length of the centrifuge lever arm (2).
The navigation solution formula in S4.3 is:
In the method, in the process of the invention, Is thatIs used for the matrix of the anti-symmetry of (a),Is the rotation speed of the earthIs used for the matrix of the anti-symmetry of (a),The acceleration of the gravity is that,Is a coordinate transformation matrix of an inertial measurement system (3) coordinate system relative to a northeast geographic coordinate system.
The inertial navigation position error model in the step S3 is as follows
Y＝CX
In which the position error sequence valueC is a matrix of environmental functions,Wherein,K=0 to N; the error coefficient of the inertial measurement system is
Where, deltaT is the calculation period,For the inertial measurement system accelerometer error, The gyroscope error of the inertial measurement system,
；
Wherein,Yaw angle, pitch angle and roll angle of the inertial measurement system relative to the northeast geographic coordinate system, respectively.
The error coefficient X of the inertial measurement system is appropriately increased or decreased according to the following accelerometer combination model and gyroscope combination model:
(a) Coefficient x a1、xa2、...、xap is selected from the error coefficients in the accelerometer combined error model:
Wherein k 0x、k0y、k0z is zero offset of an x, y and z accelerometer, and the unit is g; δk x、δky、δkz is the linearity of the x, y, z accelerometers; δK ax、δKay、δKaz is the asymmetry error coefficient of the x, y, z accelerometers; k yx、kzx、kxy、kzy、kxz、kyz is the installation error angle of the x, y and z accelerometers, and the unit is rad; k 2x、K2y、K2z is the quadratic error coefficient of the x, y and z accelerometers, the unit is g/g 2;δK2x、δK2y、δK2z is the odd quadratic error coefficient of the x, y and z accelerometers, the unit is g/g2;Kxxy、Kxxz、Kxyz、Kyxy、kyxz、kyyz、Kzxy、kzxz、kzyz is the cross coupling error coefficient of the x, y and z accelerometers, the unit is g/g 2;K3x、K3y、K3z is the cubic error coefficient of the x, y and z accelerometers, and the unit is g/g 3;
(b) The coefficient x g1、xg2、...、xgq is selected from error coefficients in the gyroscope combination error model:
Wherein D Fx、DFy、DFz is constant drift of the x, y and z gyroscopes, the unit is °/h;D1x、D1y、D1z、D2x、D2y、D2z、D3x、D3y、D3z is first term drift of the x, y and z gyroscopes, the unit is °/h/g;D4x、D4y、D4z、D5x、D5y、D5z、D6x、D6y、D6z is second term drift of the x, y and z gyroscopes, the unit is °/h/g2;D7x、D7y、D7z、D8x、D8y、D8z、D9x、D9y、D9z is cross-coupled second term drift of the x, y and z gyroscopes, and the unit is DEG/h/g 2.
The least square method in the step S3 solves the following formula:
X＝(CTC)-1CTY
In the solving process, saliency test is adopted, and the state variable which is not salient is directly set to zero.
The compensation in step S4 is to directly correct the position error, and the corrected position error Δy=y-CX.
Compared with the prior art, the invention has the following advantages:
(1) The error separation method of the inertial measurement system based on the centrifugal machine large overload excitation provided by the invention has the advantages that the higher-order error items of the inertial device are identified, and compared with a gravitational field multi-position calibration method, the method has higher confidence coefficient;
(2) The error separation method of the inertial measurement system based on the centrifugal machine large overload excitation overcomes the difficulty that the reference is inaccurate when the acceleration of the centrifugal machine is used as the reference separation error coefficient, and when the angle output by the centrifugal machine is used as the reference, on one hand, the speed error and the position error are converged, and on the other hand, the noise is eliminated by adopting integration, so that the identification accuracy and the robustness stability are improved;
(3) The invention provides an inertial measurement system error separation method based on centrifugal machine large overload excitation, which is not only applicable to high-precision centrifugal machines with stable rotating speed, but also applicable to low-precision centrifugal machines with variable rotating speed, and reduces the index requirements of equipment development.
Drawings
FIG. 1 is a schematic illustration of an inertial measurement system placed on a centrifuge inversion platform;
FIG. 2 is a schematic diagram of a centrifuge base, lever arm, and inversion platform coordinate system;
FIG. 3 is an angle of rotation of a centrifuge lever arm in an example of the present invention;
FIG. 4 is an angular velocity of rotation of a centrifuge lever arm in an example of the present invention;
FIG. 5 (a) is a real trace of the movement of a centrifuge lever arm with respect to the x-axis of the base coordinate system over time in an example of the present invention;
FIG. 5 (b) is a real trace of the movement of a centrifuge lever arm with respect to the y-axis of the base coordinate system over time in an example of the present invention;
FIG. 6 is a trajectory of the resultant movement of the centrifuge lever arm relative to the base into the plane of Ox eye in an example of the invention;
FIG. 7 (a) is a plot of navigation resolved centrifuge lever arm movement over time relative to the x-axis of the base coordinate system in an example of the present invention;
FIG. 7 (b) is a plot of navigation resolved centrifuge lever arm movement over time relative to the y-axis of the base coordinate system in an example of the present invention;
FIG. 8 is a plot of the resultant motion of the navigational-resolved centrifuge lever arm relative to the base into the Ox eye plane in an example of the present invention;
FIG. 9 (a) is a plot of x-axis position error over time in an example of the invention;
FIG. 9 (b) is a graph showing the position error in the y-axis direction over time in an example of the present invention;
FIG. 10 (a) is a diagram illustrating the trajectory of the compensated navigation solution of the present invention over time of the centrifuge lever arm relative to the x-axis of the base coordinate system;
FIG. 10 (b) is a diagram illustrating the trajectory of the compensated navigation solution of the present invention over time of the centrifuge lever arm relative to the y-axis of the base coordinate system;
FIG. 11 is a diagram illustrating the resultant trajectory of the compensated centrifuge lever arm relative to the base motion to the Ox eye plane in an example of the present invention;
Fig. 12 is a flow chart of the present invention.
Detailed Description
The invention is described in further detail below with reference to the attached drawings and to specific embodiments:
The invention provides an inertial measurement system error separation method based on centrifugal machine large overload excitation, which comprises the following steps:
s1, establishing an inertial measurement system error separation test system: a reversing platform 4 is arranged at the tail end of the centrifuge lever arm 2, a counterweight 5 is arranged at the other side of the reversing platform, the counterweight is used for balancing the mass sum of the reversing platform and an inertial measurement system, the inertial measurement system 3 is arranged on the reversing platform 4, and the reversing platform 4 rotates relative to the rotating speed of the centrifuge lever arm 2 Rotational speed of the centrifuge lever arm 2 relative to the groundIs of opposite numbers, i.eWherein ω is the rotational speed of the centrifuge lever arm 2 relative to the centrifuge base (1);
The coordinate system of the centrifuge base 1 is coincident with the northeast geographic coordinate system Ox eyeze, wherein Ox e refers to east, oy e refers to north, oz e refers to the day, and the three meet the right-hand coordinate system;
The lever arm 2 coordinate system of the centrifugal machine is Ox pypzp, wherein Ox p is coincided with the lever arm and points outwards, oy p is perpendicular to the lever arm and is positioned in the horizontal plane, oz p points day, and the three meet the right-hand coordinate system;
the coordinate system of the inversion platform 4 is Ox qyqzq, wherein Ox q and Oy q are in a horizontal plane, oz q refers to days, and the three meet a right-hand coordinate system;
The inertial measurement system 3 has a coordinate system Ox bybzb, which is oriented in the same direction as the coordinate system Ox qyqzq of the inversion stage 4.
The centrifuge is located at a position with a latitude L, a gravity acceleration g, a height h, an earth rotation speed omega ie, and a length of the centrifuge lever arm 2 is 2R.
S2, performing inertial measurement system error separation test: driving the centrifuge lever arm 2 to rotate around the base 1 at a high speed to form a centripetal acceleration which is excitation of the inertial measurement system 3 mounted on the centrifuge lever arm 2, preferably not less than 5g; the characteristic that the length of the centrifuge lever arm is unchanged is utilized, and the movement track of the inertial measurement system 3 arranged on the centrifuge lever arm 2 is obtained by combining the rotation angle of the centrifuge lever arm 2 in the rotation process and is recorded as a reference movement track; navigation and calculation are carried out on the visual acceleration of the inertial measurement system 3 to obtain a motion track with errors, and the motion track is recorded as a measurement motion track; comparing the difference value of the measured motion track and the reference motion track to obtain a position error sequence value of the inertial measurement system;
the method comprises the following steps:
S2.1, at the initial time t 0, completing the initial alignment of the inertial measurement system so that the inertial navigation coordinate system is physically coincident with the northeast ground coordinate system Ox eyeze (so that ) Or calculated by mathematical alignmentIs the initial value of (2); is a coordinate transformation matrix of the coordinate system of the inertial measurement system 3 relative to the geographic coordinate system of northeast.
S2.2, according to the measured rotation angle phi 0 of the centrifuge lever arm 2 relative to the base 1 at the initial time t 0, calculating the initial value (x ew,0,yew,0,yew,0) of the position of the inertial measurement system at the initial time t 0 relative to the northeast ground coordinate system Ox eyeze in the reference motion track, and setting the initial value of the speed of the inertial measurement system at the initial time t 0 relative to the northeast ground coordinate system Ox eyeze in the reference motion track as 0, namelyInitializing k to 1 when the next calculation period comes, and then sequentially executing the steps S2.3-S2.6;
The calculation formula of the initial value (x ew,0,yew,0,yew,0) of the position of the inertial measurement system relative to the northeast sky and ground coordinate system at the initial time t 0 in the reference motion trail is as follows:
Wherein R is half the length of the centrifuge lever arm 2.
The initial value of the position of the inertial measurement system during navigation solution is set as follows:
Namely: the position of the first track point (x en,0,yen,0,yen,0) in the measurement motion track is the same as the position of the first track point (x ew,0,yew,0,yew,0) in the reference motion track.
S2.3, according to the measured angle value of the centrifuge lever arm 2 when rotating relative to the base 1Calculating the position of the inertial measurement system at the current time t k relative to the northeast sky ground coordinate system (Ox eyeze);
the calculation formula of the initial value (x ew,k,yew,k,yew,k) of the position of the inertial measurement system relative to the northeast sky and ground coordinate system at the initial time t k in the reference motion trail is as follows:
Wherein R is half the length of the centrifuge lever arm 2.
S2.4, measuring the angular velocity according to a gyroscope in the inertial measurement systemThe accelerometer is combined to measure and obtain the apparent accelerationNavigation solution is carried out to obtain the position at the current time t k
Navigation solutions were performed using the following navigation equations:
In the method, in the process of the invention, Is thatIs used for the matrix of the anti-symmetry of (a),Is the rotation speed of the earthIs used for the matrix of the anti-symmetry of (a),Gravitational acceleration. Calculating the position at time t k according to the above method
S2.5, calculating corresponding track point position errors in the reference motion track and the measurement motion track:
S2.6, when the next calculation period arrives, returning k=k+1 to the step S3.2 to execute the steps S2.3-S2.6 again until reaching the end time t N, and entering the step S3.6;
s2.7, summarizing the position errors of corresponding track points in the reference motion track and the measurement motion track to obtain a position error sequence value Y:
S3, substituting the position error sequence value of the inertial measurement system into an inertial navigation position error model, and separating out each error coefficient of the inertial measurement system by adopting a least square method;
the inertial navigation position error model is:
Y＝CX
in which the position error sequence value C is a matrix of environmental functions,Wherein,K=0 to N; the error coefficient of the inertial measurement system is
Where, deltaT is the calculation period,For the inertial measurement system accelerometer error, The gyroscope error of the inertial measurement system,
；
Wherein,Yaw angle, pitch angle and roll angle of the inertial measurement system relative to the northeast geographic coordinate system, respectively.
The error coefficient X of the inertial measurement system is appropriately increased or decreased according to the following accelerometer combination model and gyroscope combination model:
(a) Coefficient x a1、xa2、...、xap is selected from the error coefficients in the accelerometer combined error model:
Wherein k 0x、k0y、k0z is zero offset of an x, y and z accelerometer, and the unit is g; δk x、δky、δkz is the linearity of the x, y, z accelerometers; δK ax、δKay、δKaz is the asymmetry error coefficient of the x, y, z accelerometers; k yx、kzx、kxy、kzy、kxz、kyz is the installation error angle of the x, y and z accelerometers, and the unit is rad; k 2x、K2y、K2z is the quadratic error coefficient of the x, y and z accelerometers, the unit is g/g 2;δK2x、δK2y、δK2z is the odd quadratic error coefficient of the x, y and z accelerometers, the unit is g/g2;Kxxy、Kxxz、Kxyz、Kyxy、kyxz、kyyz、Kzxy、kzxz、kzyz is the cross coupling error coefficient of the x, y and z accelerometers, the unit is g/g 2;K3x、K3y、K3z is the cubic error coefficient of the x, y and z accelerometers, and the unit is g/g 3;
(b) The coefficient x g1、xg2、...、xgq is selected from error coefficients in the gyroscope combination error model:
Wherein D Fx、DFy、DFz is constant drift of the x, y and z gyroscopes, the unit is °/h;D1x、D1y、D1z、D2x、D2y、D2z、D3x、D3y、D3z is first term drift of the x, y and z gyroscopes, the unit is °/h/g;D4x、D4y、D4z、D5x、D5y、D5z、D6x、D6y、D6z is second term drift of the x, y and z gyroscopes, the unit is °/h/g2;D7x、D7y、D7z、D8x、D8y、D8z、D9x、D9y、D9z is cross-coupled second term drift of the x, y and z gyroscopes, and the unit is DEG/h/g 2.
The least squares method solves the following equation:
X＝(CTC)-1CTY
In the solving process, saliency test is adopted, and the state variable which is not salient is directly set to zero.
S4, correcting the error of the inertial measurement system participating in navigation calculation by utilizing the determined error coefficient of the inertial measurement system, so as to realize the compensation of the navigation calculation of the inertial measurement system and improve the inertial navigation precision.
The compensation is to directly correct the position error, and the corrected position error is delta Y=Y-CX.
In the step, compensation is to correct binding values of errors of a gyroscope and an accelerometer which participate in navigation calculation by using the determined error coefficient of the inertial measurement system, so as to realize the compensation of the inertial navigation calculation.
Examples:
For vivid description of the inertial measurement system error separation method based on centrifugal machine large overload excitation, the preferred embodiment is as follows:
Let arm length of centrifuge 2 r=6m, inertial measurement system is placed on the inversion platform of centrifuge as shown in fig. 1. The relationship between centrifuge base, lever arm and inversion platform coordinate system is shown in fig. 2.
In a test, the sampling time of the rotation angle of the centrifuge is Δt=0.02 s, the running time is 255s, and the total number of data n=12750. Rotation angleAnd angular velocity ω are shown in fig. 3 and 4, respectively. Using the formula
The calculated motion trace of the centrifuge lever arm relative to the base coordinate system with time is shown in fig. 5 (a) and 5 (b), and the trace synthesized to the Ox eye plane is shown in fig. 6. Whereas the trajectory x en,k、yen,k of the centrifuge lever arm relative to the base coordinate system calculated by navigation over time is shown in fig. 7 (a) and 7 (b), the trajectory synthesized to the Ox eye plane is shown in fig. 8. As shown in fig. 9 (a) and 9 (b), the position error x en,k-xew,k、yen,k-yew,k is larger than 30m, and the y-axis maximum error is larger than 100m.
By using the error separation method of the invention, a group of significant error items is δKay＝5.17×10-4、Kzxy＝0.068g/g2、D4y＝-0.04°/h/g2、D5y＝0.43°/h/g2,, and the rest error coefficients are zero. After the four error coefficients are compensated, the motion track x en,k、yen,k of the arm of the centrifugal machine, which is obtained by carrying out navigation calculation again, relative to the base coordinate system along with time is shown in fig. 10 (a) and 10 (b), the track synthesized to the Ox eye plane is shown in fig. 11, and as can be seen from the figure, the maximum error of the x axis and the y axis is smaller than 0.5m.
Comparing fig. 11 with fig. 9 (a) and fig. 9 (b), it can be seen that according to the method of the present invention, not only significant error terms are identified, but also navigation errors are obviously eliminated, which indicates that the method of the present invention can well meet the error separation requirement under the condition of heavy overload of the centrifuge.
The above embodiment can verify that the error separation method of the inertial measurement system based on the centrifugal machine large overload excitation is correct, and fig. 12 is a flowchart for implementing the present invention.
The foregoing is merely one specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the technical scope of the present invention should be included in the scope of the present invention.
What is not described in detail in the present specification belongs to the known technology of those skilled in the art.
Claims (7)
1. The inertial measurement system error separation method based on centrifugal machine excitation is characterized by comprising the following steps:
s1, establishing an inertial measurement system error separation test system: one side end of the centrifuge lever arm (2) is provided with a reversing platform (4), the inertia measurement system (3) is arranged on the reversing platform (4), the other side is provided with a counterweight (5) for balancing the mass sum of the reversing platform and the inertia measurement system, and the rotating speed of the reversing platform (4) relative to the centrifuge lever arm (2) is realized when the reversing platform (4) rotates Rotational speed of the centrifuge lever arm (2) relative to the groundIs of opposite numbers, i.eWherein ω is the rotational speed of the centrifuge lever arm (2) relative to the centrifuge base (1);
S2, performing inertial measurement system error separation test: the centrifugal lever arm (2) is driven to rotate around the base (1) at a high speed to form centripetal acceleration, the centripetal acceleration is the excitation of the inertia measurement system (3) arranged on the centrifugal lever arm (2), and the motion trail of the inertia measurement system (3) arranged on the centrifugal lever arm (2) is obtained by combining the rotation angle of the centrifugal lever arm (2) in the rotation process by utilizing the characteristic of unchanged length of the centrifugal lever arm and is recorded as a reference motion trail; navigation and calculation are carried out on the visual acceleration of the inertial measurement system (3) to obtain a motion track with errors, and the motion track is recorded as a measurement motion track; comparing the difference value of the measured motion track and the reference motion track to obtain a position error sequence value of the inertial measurement system;
S3, substituting the position error sequence value of the inertial measurement system into an inertial navigation position error model, and separating out each error coefficient of the inertial measurement system by adopting a least square method;
s4, correcting the error of the inertial measurement system participating in navigation calculation by utilizing the determined error coefficient of the inertial measurement system, so as to realize the compensation of the navigation calculation of the inertial measurement system;
The coordinate system of the centrifuge base (1) coincides with the northeast geographic coordinate system Ox eyeze, wherein Ox e refers to east, oy e refers to north, oz e refers to the day, and the three meet the right-hand coordinate system;
The coordinates of the lever arm (2) of the centrifugal machine are Ox pypzp, wherein Ox p is overlapped with the lever arm and points outwards, oy p is vertical to the lever arm and is positioned in the horizontal plane, oz p points day, and the three meet the right-hand coordinates;
The coordinate system of the inversion platform (4) is Ox qyqzq, wherein Ox q and Oy q are in a horizontal plane, oz q refers to days, and the three meet the right-hand coordinate system;
The inertial measurement system (3) has a coordinate system Ox bybzb, which is oriented in the same direction as the coordinate system Ox qyqzq of the inversion platform (4).
2. The method for separating errors in an inertial measurement system based on excitation of a centrifuge according to claim 1, wherein the step S2 is specifically implemented as follows:
S2.1, at an initial time t 0, completing initial alignment of an inertial measurement system so that an inertial navigation coordinate system is physically coincident with a northeast geographic coordinate system Ox eyeze;
S2.2, according to the measured rotation angle of the centrifuge lever arm (2) relative to the base (1) at the initial time t 0 Calculating the initial value (x ew,0,yew,0,yew,0) of the position of the inertial measurement system relative to the northeast geographic coordinate system Ox eyeze at the initial time t 0 in the reference motion track, setting the initial value of the speed of the inertial measurement system relative to the northeast geographic coordinate system Ox eyeze at the initial time t 0 in the reference motion track as 0, initializing k as 1 when the next calculation period arrives, and then sequentially executing the steps S2.3-S2.6;
s2.3, according to the measured angle value of the centrifuge lever arm (2) rotating relative to the base (1) Calculating the position of the inertial measurement system at the current time t k relative to the northeast geographic coordinate system Ox eyeze;
s2.4, measuring the angular velocity according to a gyroscope in the inertial measurement system The accelerometer is combined to measure and obtain the apparent accelerationNavigation solution is carried out to obtain the position at the current time t k
S2.5, calculating corresponding track point position errors in the reference motion track and the measurement motion track:
Measuring the positions of corresponding track points in the motion track;
S2.6, when the next calculation period arrives, returning k=k+1 to the step S2.3 to execute the steps S2.3 to S2.6 again until reaching the end time t N, and entering the step S2.7;
s2.7, summarizing the position errors of corresponding track points in the reference motion track and the measurement motion track to obtain a position error sequence value Y:
3. the inertial measurement system error separation method based on centrifuge excitation according to claim 2, wherein in step 2.3:
The calculation formula of the initial value (x ew,k,yew,k,yew,k) of the position of the inertial measurement system at the initial time t k in the reference motion trail relative to the northeast geographic coordinate system is as follows:
wherein R is half of the length of the centrifuge lever arm (2).
4. The inertial measurement system error separation method based on centrifugal machine excitation according to claim 2, wherein the navigation solution formula in S2.4 is:
In the method, in the process of the invention, Is thatIs used for the matrix of the anti-symmetry of (a),Is the rotation speed of the earthIs used for the matrix of the anti-symmetry of (a),The acceleration of the gravity is that,Is a coordinate transformation matrix of an inertial measurement system (3) coordinate system relative to a northeast geographic coordinate system, V e is a navigation speed,For the current speed at time t k,The apparent acceleration measured for the accelerometer assembly,
5. The inertial measurement system error separation method based on centrifuge excitation of claim 4, wherein: the inertial navigation position error model in the step S3 is as follows:
Y＝CX
in which the position error sequence value C is a matrix of environmental functions,Wherein,K=0 to N; the error coefficient of the inertial measurement system is
Where, deltaT is the calculation period,For the inertial measurement system accelerometer error, The gyroscope error of the inertial measurement system,X a1、xa2、...、xap、xg1、xg2、...、xgq are error coefficients of the inertial measurement system;
；
wherein, Respectively yaw angle, pitch angle and roll angle of the inertial measurement system relative to a northeast geographic coordinate system;
the error coefficient X of the inertial measurement system is appropriately increased or decreased according to the following accelerometer combination model and gyroscope combination model:
(a) Coefficient x a1、xa2、...、xap is selected from the error coefficients in the accelerometer combined error model:
Wherein k 0x、k0y、k0z is zero offset of an x accelerometer, a y accelerometer and a z accelerometer, and the unit is g; δk x、δky、δkz is the linearity of the x accelerometer, the y accelerometer, and the z accelerometer; δK ax、δKay、δKaz is the asymmetry error coefficient of the x accelerometer, the y accelerometer, and the z accelerometer; k yx、kzx、kxy、kzy、kxz、kyz is the installation error angle of the x accelerometer, the y accelerometer and the z accelerometer, and the unit is rad; k 2x、K2y、K2z is the quadratic error coefficient of the x accelerometer, the y accelerometer and the z accelerometer, the unit is g/g 2;δK2x、δK2y、δK2z is the odd quadratic error coefficient of the x accelerometer, the y accelerometer and the z accelerometer, the unit is g/g2;Kxxy、Kxxz、Kxyz、Kyxy、kyxz、kyyz、Kzxy、kzxz、kzyz is the cross coupling term error coefficient of the x accelerometer, the y accelerometer and the z accelerometer, the unit is g/g 2;K3x、K3y、K3z is the cubic error coefficient of the x accelerometer, the y accelerometer and the z accelerometer, and the unit is g/g 3;
(b) The coefficient x g1、xg2、...、xgq is selected from error coefficients in the gyroscope combination error model:
Wherein D Fx、DFy、DFz is constant drift of the x, y and z gyroscopes, the unit is °/h;D1x、D1y、D1z、D2x、D2y、D2z、D3x、D3y、D3z is first term drift of the x, y and z gyroscopes, the unit is °/h/g;D4x、D4y、D4z、D5x、D5y、D5z、D6x、D6y、D6z is second term drift of the x, y and z gyroscopes, the unit is °/h/g2;D7x、D7y、D7z、D8x、D8y、D8z、D9x、D9y、D9z is cross coupling second term drift of the x, y and z gyroscopes, and the unit is DEG/h/g 2.
6. The inertial measurement system error separation method based on centrifugal machine excitation of claim 5, wherein: the least square method in the step S3 solves the following formula:
X＝(CTC)-1CTY
In the solving process, saliency test is adopted, and the state variable which is not salient is directly set to zero.
7. The inertial measurement system error separation method based on centrifugal machine excitation of claim 5, wherein: the compensation in step S4 is to directly correct the position error, and the corrected position error Δy=y-CX.
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| CN106643792A (en) * | 2016-10-26 | 2017-05-10 | 中国科学院长春光学精密机械与物理研究所 | Inertial measurement unit and geomagnetic sensor integrated calibration apparatus and calibration method |
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