Odometer-assisted in-transit coarse alignment position compensation method and computer device

Abstract

The application provides a kind of odometer assisted rough alignment position compensation method and computer equipment in travel, the method utilizes the rough alignment characteristics based on odometer in travel and odometer dead reckoning characteristics, converts the odometer increment under the navigation coordinate system after the conversion navigation back to the mileage increment under the initial solidification coordinate system by coordinate transformation, and accumulates the mileage increment under the solidification coordinate system in real time during navigation, converts the mileage increment under the solidification coordinate system accumulation amount to the navigation coordinate system in real time after rough alignment convergence, can compensate the position of vehicle in real time during rough alignment process of vehicle in travel, and the higher the rough alignment convergence precision is, the higher the positioning precision during alignment process of vehicle in travel is.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of inertial navigation, and relates to a rough alignment position compensation method in a running state assisted by an odometer and a computer device. BACKGROUND

[0002] Initial alignment is a very important field in the direction of inertial navigation, and the accuracy of initial alignment directly determines the accuracy of subsequent navigation. Initial alignment is divided into rough alignment and fine alignment, and the purpose of rough alignment is to obtain a relatively accurate attitude in a short time and shorten the time required for fine alignment. A commonly used initial alignment method requires an inertial navigation system to remain stationary for a period of time, which greatly affects the mobility and reaction time of a vehicle. Therefore, the use of alignment in a running state can greatly improve the mobility of the vehicle.

[0003] The alignment in a running state cannot be completed by using only the inertial navigation system, and the motion information of the carrier needs to be provided by an external device. Due to the autonomy and concealment of the vehicle-mounted wheeled odometer, the inertial navigation system is well matched with the characteristics of not radiating signals. The alignment in a running state assisted by the odometer can be implemented without any external signal input, and is an important branch in the field of alignment technology.

[0004] The purpose of alignment in a running state is to provide an accurate attitude for subsequent navigation, and the fundamental purpose is to navigate and position. However, most of the current alignment methods in a running state only consider the attitude accuracy and ignore the position accuracy in the alignment process in a running state. In particular, during the alignment process in a running state, navigation calculation before the attitude is determined will cause a large position error, and if the vehicle position is not corrected after the alignment is completed, the positioning result in the subsequent vehicle navigation process will be affected. SUMMARY

[0005] The present application aims to at least solve one of the problems in the prior art or related art.

[0006] To this end, the present application provides a rough alignment position compensation method in a running state assisted by an odometer and a computer device, which solves the problem of divergence of positioning accuracy in the alignment process in a running state.

[0007] The technical solution of the present application is as follows:

[0008] According to one aspect, a rough alignment position compensation method in a running state assisted by an odometer is provided, and the compensation method comprises the following steps:

[0009] Step 1: calculating the attitude change of the inertial navigation system under the carrier system and the influence of the earth rotation on the attitude

[0010] Step two, using inertial navigation and odometer data for travel alignment, calculating the inertial navigation attitude change from time 0 to t in real time after starting travel alignment k tk Projecting the mileage increment back to the solidified coordinate system Where b(0) is the inertial navigation carrier coordinate system at time 0, referred to as the solidified coordinate system;

[0011] Step three, obtaining the attitude output of travel alignment at time 0 According to And And Obtain the real-time attitude output during coarse alignment;

[0012] Step four, according to the initial position p(0) of the vehicle, the results obtained in step two, and the travel coarse alignment output characteristics obtained in step three, obtain the position compensation equation during travel alignment, as shown in the following formula, and complete the position compensation during travel coarse alignment based on the compensation equation;

[0013]

[0014] Where p(t k ) is the vehicle position output at time t k

[0015]

[0016] R Mh = R e (1-2f+3fsin 2 L)

[0017] R Nh = R e (1+fsin 2 L)

[0018] Where p(t k ) is the vehicle position output at time t k , R e is the long semi-axis of the earth, f is the earth's flattening, and L is the local latitude.

[0019] Further, the attitude change of the inertial navigation system in the carrier coordinate system is calculated by the following formula

[0020]

[0021] Where, is the output angular velocity of the gyroscope, and​​​​​ for An antisymmetric matrix.

[0022] Furthermore, the effect of Earth's rotation on attitude is calculated using the following formula.

[0023]

[0024] in, Earth's rotational angular velocity and the angular velocity of the change from the navigation coordinate system to the geographic coordinate system constitute, for An antisymmetric matrix.

[0025] Furthermore, in step three, the real-time attitude output during coarse alignment... Obtained through the following formula:

[0026]

[0027] According to another aspect, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described above.

[0028] The above technical solution utilizes the in-journey coarse alignment characteristics based on odometers and the dead reckoning characteristics of odometers to transform the odometer increment in the navigation coordinate system after switching to navigation back to the initial fixed coordinate system through coordinate transformation. During navigation, the odometer increment in the fixed coordinate system is accumulated in real time. After coarse alignment convergence, the accumulated odometer increment in the fixed coordinate system is transformed back to the navigation coordinate system in real time. This allows for real-time compensation of the vehicle's position during the in-journey coarse alignment process. The higher the coarse alignment convergence accuracy, the higher the positioning accuracy of the vehicle during the in-journey alignment process. Attached Figure Description

[0029] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0030] Figure 1 This is a schematic diagram of the principle of the present invention. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0034] like Figure 1 As shown, in one embodiment of the present invention, an odometer-assisted coarse alignment position compensation method for on-the-go travel is provided, the compensation method comprising:

[0035] Step 1: Calculate the attitude change of the inertial navigation system under the carrier system. and the impact of Earth's rotation on attitude.

[0036] Step 2: Perform in-journey alignment using inertial navigation and odometry data. After starting in-journey alignment, calculate the time from 0 to t in real time. k Inertial navigation attitude change at time And the odometer output increment dS tkMileage increments projected back to the solidified coordinate system And for mileage increments Perform real-time accumulation Where b(0) is the inertial navigation carrier coordinate system at time 0, called the solidification coordinate system;

[0037] Step 3: Obtain the attitude output during the alignment at time 0. according to and the result obtained in step one and Obtain the real-time attitude output during coarse alignment;

[0038] Step 4: Based on the vehicle's initial position p(0), the results obtained in Step 2, and the coarse alignment output characteristics obtained in Step 3, obtain the position compensation equation during the alignment process, as shown in the following equation, and complete the position compensation during the coarse alignment process based on the compensation equation.

[0039]

[0040] Where p(t) k ) for t k The vehicle position is output in real time.

[0041] R Mh =R e (1-2f+3fsin 2 L)

[0042] R Nh =R e (1+fsin 2 L)

[0043] Where p(t) k ) for t k The vehicle position output at any time, R e Let f be the Earth's semi-major axis, f be the Earth's oblateness, and L be the local latitude.

[0044] That is, in step one of this embodiment, the initial position p(0) of the vehicle is input, and sensor data, including gyroscope data, is acquired in real time. Accelerometer data f b Using odometry data dS, we calculated the attitude changes of the inertial navigation system under the carrier system and the impact of the Earth's rotation on the attitude:

[0045] in They are respectively and An antisymmetric matrix. The gyroscope outputs angular velocity. Earth's rotational angular velocity and the angular velocity of the change from the navigation coordinate system to the geographic coordinate system Composition, under vehicle conditions much smaller so It can be approximated as equal to That is, in this embodiment, we take equal

[0046] In step three of this embodiment, the real-time attitude output during coarse alignment... Obtained through the following formula:

[0047]

[0048] As can be seen, the embodiments of the present invention utilize the odometer-based coarse alignment characteristics and odometer dead reckoning characteristics to convert the odometer increment in the navigation coordinate system after navigation back to the initial fixed coordinate system through coordinate transformation. During navigation, the odometer increment in the fixed coordinate system is accumulated in real time. After coarse alignment convergence, the accumulated odometer increment in the fixed coordinate system is converted back to the navigation coordinate system in real time. This enables real-time compensation of the vehicle's position during the coarse alignment process. The higher the coarse alignment convergence accuracy, the higher the positioning accuracy of the vehicle during the alignment process.

[0049] According to another embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method of the above embodiment.

[0050] To provide a better understanding of the compensation method of the present invention, a specific embodiment is described in detail below:

[0051] This embodiment provides an odometer-assisted method for coarse alignment position compensation during travel, specifically including:

[0052] The first step is to input the vehicle's initial latitude and longitude p(0) and acquire gyroscope data in real time. Accelerometer data f b Using odometry data dS, we calculated the attitude changes of the inertial navigation system and the change in attitude due to the Earth's rotation within the system: This facilitates subsequent alignment calculations during movement;

[0053] The second step, since the inertial navigation data and odometry data have the same frequency, is to calculate the time from 0 to t in real time after the alignment begins during travel. k Inertial navigation attitude change at time And the odometer output increment dS tk Mileage increment projected back to time 0 And the mileage increment is accumulated in real time.

[0054] The third step involves using inertial navigation and odometry data to perform real-time coarse alignment during travel and calculating the attitude matrix at time 0. The specific calculation process is as follows:

[0055] 1) Decomposing the specific force equation in the n-system yields:

[0056] Where V is the vehicle's speed in the geographic system. Let g be the attitude matrix of the inertial device at time t. n This refers to the acceleration due to Earth's gravity.

[0057] 2) The basic formula transformation can be used to... Decomposed into:

[0058]

[0059] 3) Combine the expressions in 1) and 2) and multiply both terms on the left simultaneously. get:

[0060]

[0061] 4) Integrating both sides simultaneously, we get:

[0062] in

[0063]

[0064] neglect Equal to small quantities, and discretized by quadratic fitting to obtain:

[0065]

[0066] Where T is the sampling interval, which is typically 0.1 seconds or 1 second. k =kT,k=0,1,2...N-1. Δθ1, Δθ2, ΔV1 and ΔV2 are respectively t k-1 to t k The angle and velocity increments of the gyroscope and accelerometer outputs within the sampling interval. It can be obtained by averaging the odometer output over the sampling interval.

[0067] 5) The QUEST algorithm can be used to solve for the solution in 4). The optimal solution, i.e. the optimal alignment result of coarse alignment.

[0068] 6) Output the attitude matrix result of the alignment during travel.

[0069] The fourth step is to calculate the positioning equations based on dead reckoning:

[0070]

[0071] Where p(t) is the vehicle position output at time t, and p(0) is the vehicle position initially loaded at time 0. For t k The attitude matrix of the carrier at any given time. For a short period of time [t] k-1 t k The mileage increment of the vehicle's onboard odometer.

[0072] The conventional method is to use the real-time attitude output during the in-journey alignment in step 3(6). To calculate the position p(t). However, when the attitude has not converged, using an attitude matrix with a large error is problematic. Real-time dead reckoning will cause a large error in the position p(t);

[0073] Combining the output characteristics of coarse alignment during travel in step 3(5), Decomposed into Due to the short period of time and For a more accurate value, in the alignment result By performing dead reckoning and positioning calculations after convergence, the positioning accuracy during the alignment process can be improved.

[0074] The dead reckoning and positioning solution equations will be transformed into

[0075]

[0076] because This value changes little during the coarse alignment time and can be considered constant. Let be the attitude matrix of the carrier at the initial moment, so It can also be regarded as a constant value. Taking out the summation part yields

[0077]

[0078] Based on the principle of alignment in motion, the attitude matrix at time 0 can be output in real time during the alignment process. If the mileage increment is accumulated in real time during the alignment process The above formula can be used to complete the position compensation during the coarse alignment process while moving.

[0079] In summary, the solution proposed in this invention utilizes differential satellite receiver positioning results to replace the traditional CPIII control point + total station optical measurement method, significantly improving measurement speed. Furthermore, it ensures that the inertial / odometer combined trajectory, after correcting for system errors, falls within the error band of the satellite measurement results, while preserving track smoothness characteristics, thereby achieving high-precision absolute measurement based on differential satellite receiver trajectory constraints.

[0080] The features described and / or illustrated above with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, and / or in combination with or in lieu of features in other embodiments.

[0081] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, components, or combinations thereof.

[0082] The methods described above in this invention can be implemented in hardware or in combination with software. This invention relates to computer-readable programs that, when executed by a logic component, enable the logic component to implement the aforementioned apparatus or constituent parts, or to implement the various methods or steps described above. This invention also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, etc.

[0083] Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of the invention are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

[0084] The parts of this invention not described in detail are techniques known to those skilled in the art.

Claims

1. A method for coarse alignment position compensation during travel assisted by an odometer, characterized in that, The compensation method includes: Step 1: Calculate the attitude change of the inertial navigation system under the carrier system. and the impact of Earth's rotation on attitude. Step 2: Perform in-journey alignment using inertial navigation and odometry data. After starting in-journey alignment, calculate the time from 0 to t in real time. k Inertial navigation attitude change at time And the odometer output increment dS tk Mileage increments projected back to the solidified coordinate system And for mileage increments Perform real-time accumulation Where b(0) is the inertial navigation carrier coordinate system at time 0, called the solidification coordinate system; Step 3: Obtain the attitude output during the alignment at time 0. according to and the result obtained in step one and Obtain the real-time attitude output during coarse alignment; Step 4: Based on the vehicle's initial position p(0), the results obtained in Step 2, and the coarse alignment output characteristics obtained in Step 3, obtain the position compensation equation during the alignment process, as shown in the following equation, and complete the position compensation during the coarse alignment process based on the compensation equation. Where p(t) k ) for t k The vehicle position output at any time, M pv The formula is: R Mh =R e (1-2f+3fsin 2 L) R Nh =R e (1+fsin 2 L) Where p(t) k ) for t k The vehicle position output at any time, R e Let f be the Earth's semi-major axis, f be the Earth's oblateness, and L be the local latitude.

2. The method for coarse alignment position compensation during travel assisted by an odometer according to claim 1, characterized in that, The attitude change of the inertial navigation system under the following formula is calculated. in, The gyroscope outputs angular velocity, where for An antisymmetric matrix.

3. The method for odometer-assisted coarse alignment position compensation during travel according to claim 2, characterized in that, The effect of Earth's rotation on attitude is calculated using the following formula. in, Earth's rotational angular velocity and the angular velocity of the change from the navigation coordinate system to the geographic coordinate system constitute, for An antisymmetric matrix.

4. A method for coarse alignment position compensation during travel assisted by an odometer, as described in claims 1-3, is characterized in that... In step three, the real-time attitude output during coarse alignment Obtained through the following formula:

5. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method described in claims 1-4.

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