WO2014133235A1

WO2014133235A1 - Method for optimizing sensitivity of gyroscope for magnet-gyro guidance device

Info

Publication number: WO2014133235A1
Application number: PCT/KR2013/006942
Authority: WO
Inventors: 김성신; 배선일; 김재용; 정경훈; 김정민
Original assignee: (주)아티스
Priority date: 2013-02-26
Filing date: 2013-08-01
Publication date: 2014-09-04
Also published as: KR101393063B1

Abstract

The present invention relates to a method for optimizing the sensitivity of a gyroscope for a magnet-gyro guidance device which guides driving by means of a first encoder and a second encoder for respectively measuring the angular velocity of wheels on both sides with respect to a moving object and a gyroscope for measuring the angular velocity of a vehicle body. The method comprises the steps of: when the moving object is driven in a first direction, if the rotation of the moving object is completed such that the angle of the moving object calculated by the first encoder meets a predefined angle, calculating a binary string of the sensitivity of a gyroscope having the lowest average value of angle errors calculated by using an accumulated output value of the gyroscope, the predefined angle and [formula 11]; and calculating the optimum sensitivity of the gyroscope in the first direction by using [formula 12] while fixing the length of the calculated binary string and varying the value of the binary string according to the search direction. Since the method optimizes the sensitivity of a gyroscope on a measurement system of the gyroscope, it is possible to calculate the accurate sensitivity of the gyroscope including the characteristics of the measurement system and the environment in which the gyroscope is installed.

Description

Gyro Sensitivity Optimization Method for Self-Gyro Guidance Devices

The present invention relates to a method for optimizing the sensitivity of a gyro for a self-gyro guiding device, in particular, in a system for measuring a gyro mounted on a moving object in order to optimize the sensitivity of a gyro that varies according to the installed position gradient and the performance of a measurement system. The present invention relates to a method for optimizing sensitivity of a gyro for a self-gyro guiding apparatus that optimizes respective sensitivity to rotations in a left direction and a right direction by an optimization technique.

In general, MEMS (Micro Electro Mechanical System) type gyro is smaller, lower power, and more expensive than conventional fluid, optical fiber and ring laser gyros.

Therefore, in most systems measuring angular velocity values, MEMS gyro is mainly used.

However, MEMS-type gyros have significantly less drift, linearity, and angular velocity accuracy than other gyros.

Thus, many conventional inventions have been made to increase the sensitivity precision of the gyro.

In a sensitivity correction invention of a typical representative MEMS gyro, a method using an average value of the gyro's angular velocity is used.

This is a method of selecting a weight corresponding to the rotation angle with the average angular velocity value calculated by rotating the gyro at a certain angle and accumulating the measured rotation angle for a specific time.

However, since the method using the average angular velocity does not consider the influence of the gyro or the system at all, the precision varies depending on the system to be mounted.

In addition, since the sensitivity of the gyro is calculated from the average angular velocity value, the exact sensitivity could not be calculated.

Thus, a method of optimizing the sensitivity of the gyro by using a rotating device other than the basic system was invented.

However, there is a problem that the cost increases and bulky to use a separate device.

Thus, a method of correcting the sensitivity of a gyro by directly rotating a moving body mounted with a gyro has been invented.

This method is to calculate the sensitivity by calculating the characteristic curve of the angular velocity measured by the gyro by directly rotating the moving object, and it is necessary to use a high-cost microcontroller unit (MCU) because of the large amount of computation because the characteristic curve has to be calculated. A separate device was needed to measure absolute angles.

In addition, the conventional methods have an angular velocity error according to the rotation direction by correcting only the gyro sensitivity in one direction.

The present invention has been developed to solve the above problems, a magnetic-gyro guidance device for optimizing the sensitivity of the gyro on the gyro measurement system to include the position of the gyro mounted on the moving object and the characteristics of the measurement system The purpose of the present invention is to provide a method for optimizing sensitivity of the gyro.

It is another object of the present invention to provide a gyro sensitivity optimization method for a gyro guiding device that can optimize the sensitivity of a gyro without a separate instrument and an absolute angle measuring device in addition to the self-gyro guideless unmanned vehicle. .

Gyro sensitivity optimization method for a self-gyro guiding apparatus according to the present invention for achieving the above object,

In the sensitivity optimization method of the gyro for the first and second encoders for measuring the angular velocity of both wheels relative to the moving body and the self-gyro guidance device for driving the gyro for measuring the angular velocity of the vehicle body,

When the moving body angles calculated by the first and second encoders have completed rotation at the set angle when the moving body is driven in the first direction, the output value of the accumulated gyro, the set angle, and the angle obtained by Equation 1 below Obtaining a binary string of gyro sensitivity having a smallest mean value of the errors;

Equation 1

Where f (x) is the mean value of the angle error, TD is the set angle, x is the output value of the accumulated gyro, N is the number of data of the accumulated gyro, O (or, f _d (b _m-1 b _{m- B} ... b ₁ b ₀ ) is the sensitivity and b is the binary string.

Comprising a fixed length of the obtained binary string and varying the value according to the search direction to calculate the optimal sensitivity of the gyro in the first direction by the following equation (2).

Equation 2

Preferably, calculating the gyro measurement angle by multiplying (x) the output value of the gyro obtained by rotating the optimal sensitivity and the set angle by the calculated gyro, and the angle error obtained by subtracting the gyro measurement angle from the set angle is set. When the threshold value is exceeded, the optimum sensitivity of the gyro in the first direction is calculated again, and when the angle error obtained by subtracting the gyro measurement angle from the set angle is less than or equal to the set threshold, the optimal sensitivity of the gyro is determined. And further setting the final sensitivity to the optimum sensitivity in the direction.

And, when the angle error obtained by subtracting the gyro measurement angle from the set angle is less than the set threshold,

Calculate an optimum sensitivity in the second direction of the moving body,

The calculation is,

When the moving body angles calculated by the first and second encoders are completed at the set angle when the moving body is driven in the second direction, the output value of the accumulated gyro, the set angle, and the angle obtained by Equation 3 below Obtaining a binary string of gyro sensitivity having a smallest mean value of the errors;

Equation 3

Calculating the optimal sensitivity of the gyro in the second direction by the following Equation 4 while fixing the length of the obtained binary string and varying the value according to the search direction.

Equation 4

The present invention has the following effects.

First, by optimizing the sensitivity of the gyro on the gyro measurement system, accurate sensitivity of the gyro can be calculated, including the environment of the gyro and the characteristics of the measurement system.

Secondly, it is possible to implement a high-precision gyro system at a low cost by using the eastern encryption optimization technique that can be robustly optimized even in a low-performance microcomputer.

Third, the gyro's sensitivity can be optimized for right and left rotations, respectively, to measure accurate angular velocities regardless of direction.

1 is a view showing the configuration of a self-gyro guided unmanned vehicle according to the present invention

2 is a flowchart illustrating a gyro sensitivity optimization method according to the present invention in order

Figure 3 is a flow chart showing in order the eastern call optimization technique according to the present invention

4 is a flowchart illustrating a sequence of Bisectional Search (BSS) procedures according to the present invention.

5 is a flow chart showing the UDS procedure in order according to the present invention

Explanation of symbols on the main parts of the drawings

1: self-gyro guided unmanned vehicle 2: body

3: wheel 10: control system

11: microcomputer 12: magnetic positioning sensor

13: encoder 14: gyro

Hereinafter, with reference to the accompanying drawings will be described the present invention.

However, the embodiments described below are merely to describe in detail enough to be able to easily carry out the invention by those skilled in the art to which the present invention pertains, and this is because the scope of protection of the present invention is limited. It does not mean.

In order to clearly describe the present invention, parts irrelevant to the description are omitted and like reference numerals denote like parts throughout the specification.

Throughout the specification and claims, when a part includes a certain component, it means that it may include other components, not to exclude other components unless specifically stated otherwise.

1 is a diagram illustrating a configuration of a self-gyro guided unmanned vehicle according to the present invention.

As shown in FIG. 1, the self-gyro guiding unmanned vehicle 1 according to the present invention is largely composed of a body 2, a wheel 3, and a control system 10, and a control system 10. Is again a microcomputer 11 for controlling and measuring motors and sensors, a magnetic positioning sensor 12 for measuring the position of a cylindrical magnet embedded in the floor, an encoder 13 for measuring the angular velocity of the wheel, and an angular velocity of the vehicle body. It consists of a gyro 14 for measurement.

The self-gyro guiding unmanned vehicle 1 thus constructed is guided by using the angular velocity measured and calculated by the encoder 13 and the gyro 14, and the magnetic positioning sensor 12 embeds the cylindrical magnet embedded in the floor. When measured, it is a way to correct the position and angle of the unmanned vehicle (1).

This has the advantage of being very easy to install and maintain compared to other induction methods because the sparse buried cylindrical magnet on the floor.

However, if the performance of the gyro is not good, the distance between the cylindrical magnets becomes narrow, so that many cylindrical magnets need to be installed on the floor, so the self-gyro induction method itself is meaningless.

Therefore, sensitivity correction of the MEMS type gyro, which has much lower drift, linearity, and angular velocity accuracy than other gyros, is very important.

2 is a flowchart illustrating a procedure flow of a gyro sensitivity optimization method according to the present invention in order.

As shown in Figure 2, the present invention, first, when the self-gyro guided unmanned vehicle 1 travels to the right (S101), unmanned transport with an encoder 13 installed in the motor of the unmanned vehicle (1) The angle of the difference 1 is calculated (S102), and the output of the gyro 14 is accumulated (S103).

Next, when the calculated angle of the unmanned vehicle 1 is completed to rotate the set angle ( TD ) (S104), the unmanned vehicle (1) is stopped (105) and the output of the accumulated gyro and the set angle ( TD ) The gyro sensitivity ( S _r ) in the right direction is found by using the eastern encryption optimization technique (S200).

Then, calculate the angular error ( E _sr ) by the sensitivity of the found gyro ( S _r ) (S106) and if the threshold ( T ) is exceeded (S107), the gyro sensitivity ( S _r ) of the right direction is again determined by the eastern encryption optimization technique. Find (S200).

That is, the gyro measurement angle is obtained by multiplying (x) the output value of the gyro obtained by rotating the set gyro with the optimum sensitivity of the found gyro, and the angle error obtained by subtracting the gyro measurement angle from the set angle exceeds the set threshold. In one case, the optimal sensitivity of the gyro in the right direction is calculated again (S200).

On the other hand, when the angle error obtained by subtracting the gyro measurement angle from the set angle is less than the set threshold, the optimum sensitivity of the gyro is finally set to the optimum sensitivity in the right direction.

Next, when the angle error E _sr is equal to or less than the threshold T (S107), the unmanned vehicle starts to drive on the left side (S108), and the unmanned vehicle (1) is installed by the encoder 13 installed in the motor of the unmanned vehicle (1). While calculating the angle of (S109) accumulates the output of the gyro 14 (S110).

When rotation of the calculated unmanned vehicle 1 is completed by the set angle TD (S111), the unmanned vehicle 1 is stopped (112) and based on the accumulated output of the gyro and the set angle ( TD ). The gyro sensitivity ( S _l ) of the left direction is found by using the eastern encryption optimization technique (S210).

Then, calculate the angular error ( E _sl ) by the sensitivity of the found gyro ( S _l ) (S113) and if exceeding the threshold ( T ) (S114) again, the gyro sensitivity ( S _r ) of the left direction by the eastern encryption optimization technique. Find (S210).

That is, the gyro measurement angle is obtained by multiplying (x) the output value of the gyro obtained by rotating the set gyro with the optimum sensitivity of the found gyro, and the angle error obtained by subtracting the gyro measurement angle from the set angle exceeds the set threshold. In one case, the optimal sensitivity of the gyro in the left direction is calculated again (S210).

On the other hand, if the angle error obtained by subtracting the gyro measurement angle from the set angle is less than the set threshold, the optimum sensitivity of the gyro is finally set to the optimum sensitivity in the left direction.

If the angular error E _sr is less than or equal to the threshold T (S114), the optimization of the sensitivity of the gyro ends.

Figure 3 shows the entire flow chart of the method of calculating the gyro sensitivity (S200, S210) using the eastern call optimization method according to the present invention.

First, when the sensitivity optimization of the gyro starts, the present invention counts the number of executions t (S211) and randomly selects a search position from the global position (S212).

Next, it is checked whether the selected starting position overlaps the history (S213), and if overlapping, a new search starting position is randomly selected from the global position again (S212).

If there is no overlap, the optimal solution is derived by generating neighbor search positions that are opposite to each other in the selected search position through a bisectional search (BSS) step and comparing the calculated objective function value with the generated neighbor value (S300).

Next, when the optimal solution is derived, the UDS step (S400) of searching for the surrounding area is performed by increasing and decreasing until the value of the objective function becomes optimal.

After the UDS step (S400), check whether the number of executions ( t ) has been performed by the number of repetitions ( n ) (S214). If the number of executions ( t ) has not been performed by the number of repetitions ( n ), add a search start position to the history ( S215) is repeated again from the beginning.

If the number of executions t is performed by the number of repetitions n , the sensitivity search of the gyro is completed.

In the BSS step S300, a local search for an optimal solution is found by using a characteristic in which a real value decreases when a decoding is performed by attaching 0 to a least significant bit (LSB) of a binary string, and a real value increases when a decoding is performed by attaching a 1. Corresponds to the technique.

4 shows a flowchart of a BSS step in accordance with the present invention.

First, binary string data other than the search position is initialized (S301) and 2 ⁿ neighbor search positions are generated by adding 0 and 1 to the least significant bit of the binary string corresponding to the search position (S302).

In order to create a binary string corresponding to the generated neighbor search position, decoding is performed as shown in Equation 5 (S303).

Equation 5

Here, O (or f _d (b _m-1 b _m-2 ... B ₁ b ₀ ) is sensitivity and b is a binary string.

Next, a cost function is calculated by substituting the decoded value O into an objective function as shown in Equation 6 (S304).

Equation 6

Here, f (x) represents an average value of the angular error, TD represents a set angle, x represents an output value of the accumulated gyro, and N represents the number of accumulated gyro data.

Next, the cost values calculated through the cost function are compared with each other (S305), and finally the smallest value is selected as the optimal solution (S306).

Thus, a binary string of gyro sensitivity having the smallest mean value of the angular error is obtained.

5 shows a flowchart of the UDS step according to the present invention.

The UDS step is to calculate the optimal sensitivity of the gyro in the corresponding direction while fixing the length of the binary string obtained through the BSS step and varying the value according to the search direction.

Specifically, it is as follows.

First, if the BSS step S300 is a concentrated search for finding an optimal solution by changing the length of the string, the UDS step S400 has a feature of a wide area search for searching a wide range without changing the length of the string.

Unlike the BSS step S300, the UDS step S400 is repeatedly performed until the length of the binary string is fixed and the cost value no longer decreases.

The UDS step (S400) first initializes binary string data (S401) and checks whether or not a limit (S402).

The step of checking the limit (S402) is to exclude the maximum and minimum that the binary string can represent, and to find a string having all zeros or ones in the series of binary strings and excludes it from the UDS step (S400).

If there is a search position at the limit position (S402), the UDS step S400 is terminated, otherwise (S402) it is checked whether the overlap (S403).

The step of confirming the overlapping step (S403) excludes the search position, which has been calculated once, and compares the value of the previous optimal solution with the optimal search position to be searched.

If the search positions overlap (S403), the UDS step S400 is terminated, otherwise (S403), decoding is performed through Equation 5 (S404).

Then, the decoded value is put into Equation 6 to calculate the cost value O _t (S405).

If the calculated cost value ( O _t ) is greater than the previously calculated cost value ( O _t-1 ) (S408), the length of the binary string of the current search position is fixed to select another search position (S409). , The process returns to the step of checking the limit (S402).

If the calculated cost value O _t is smaller than the previously calculated cost value O _t-1 (S408), the UDS step S400 is completed.

As described above, the eastern optimization method that proposes the solution of the nonlinear optimization problem finds the local and global optimal solutions using only well-planned computer operations, unlike other optimal methods that find the optimal solution of the objective function using differentials.

In order to optimally detect the gyro sensitivity value, an optimization technique should be used on the measurement system to reflect the position gradient of the gyro installed in the moving object and the characteristics of the measurement system.

However, the existing optimization methods have to perform higher-order differential calculations, resulting in large computational errors and high cost of microcomputers.

Therefore, the sensitivity optimization method of the gyro using the eastern encryption optimization method expresses the optimal solution in binary, so that the source code is optimized, so that the optimal solution can be searched robustly and quickly even in the low specification microcomputer.

This not only reduces costs, but also makes it possible to design the system robustly and to explore the sensitivity of the optimized gyro reflecting all the characteristics of the gyro installed in the moving object.

In addition, the sensitivity of the right direction and the left direction can be searched by the optimization technique, respectively, to realize a high precision gyro system regardless of the direction.

It will be understood that the present invention is implemented in a modified form without departing from the essential features of the present invention as described above.

Therefore, the described embodiments should be considered in descriptive sense only and not for purposes of limitation, and the scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the equivalent scope are included in the present invention. It should be interpreted.

The present invention relates to a method for optimizing the sensitivity of a gyro for a self-gyro guiding device, in particular, in a system for measuring a gyro mounted on a moving object in order to optimize the sensitivity of a gyro that varies according to the installed position gradient and the performance of a measurement system. As an optimization technique, it is used in the gyro sensitivity optimization method for the self-gyro guiding device which optimizes the respective sensitivity to rotation in the left direction and the right direction.

Claims

In the sensitivity optimization method of the gyro for the first and second encoders for measuring the angular velocity of both wheels relative to the moving body and the self-gyro guidance device for driving the gyro for measuring the angular velocity of the vehicle body,

When the moving body angles calculated by the first and second encoders have completed rotation at the set angle when the moving body is driven in the first direction, the output value of the accumulated gyro, the set angle, and the angle obtained by Equation 7 below Obtaining a binary string of gyro sensitivity having a smallest mean value of the errors;

[Equation 7]

Where f (x) is the mean value of the angle error, TD is the set angle, x is the output value of the accumulated gyro, N is the number of data of the accumulated gyro, O (or, f d (b m-1 b m- B ... b 1 b 0 ) is the sensitivity and b is the binary string.

Deriving the length of the obtained binary string and varying the value according to the search direction, the following equation [8], self-gyro derived comprising the step of calculating the optimal sensitivity of the gyro in the first direction How to optimize gyro sensitivity for your device.

[Equation 8]

Where f (x) is the mean value of the angle error, TD is the set angle, x is the output value of the accumulated gyro, N is the number of data of the accumulated gyro, O (or, f d (b m-1 b m- B ... b 1 b 0 ) is the sensitivity and b is the binary string.
The method of claim 1,

Obtaining a gyro measurement angle by multiplying (x) the output value of the gyro obtained by rotating the optimal sensitivity and the set angle of the calculated gyro; And

When the angle error obtained by subtracting the gyro measurement angle from the set angle exceeds the set threshold, the optimum sensitivity of the gyro in the first direction is calculated again, and the angle error obtained by subtracting the gyro measurement angle from the set angle Is finally set to an optimal sensitivity of the corresponding gyro to an optimal sensitivity in the first direction, when the value is less than or equal to a predetermined threshold.
The method of claim 2,

If the angle error obtained by subtracting the gyro measurement angle from the set angle is less than the set threshold,

Calculate an optimum sensitivity in the second direction of the moving body,

The calculation is

When the moving body angle calculated by the first and second encoders is completed at the set angle when the moving body is driven in the second direction, the output value of the accumulated gyro, the set angle, and the angle obtained by Equation 9 below Obtaining a binary string of gyro sensitivity having a smallest mean value of the errors;

[Equation 9]

Where f (x) is the mean value of the angle error, TD is the set angle, x is the output value of the accumulated gyro, N is the number of data of the accumulated gyro, O (or, f d (b m-1 b m- B ... b 1 b 0 ) is the sensitivity and b is the binary string.

Calculating the optimal sensitivity of the gyro in the second direction by the following Equation 10 while fixing the length of the obtained binary string and varying the value according to the search direction. Gyro Sensitivity Optimization Method for Self-Gyro Guidance Devices.

[Equation 10]

Where f (x) is the mean value of the angle error, TD is the set angle, x is the output value of the accumulated gyro, N is the number of data of the accumulated gyro, O (or, f d (b m-1 b m- B ... b 1 b 0 ) is the sensitivity and b is the binary string.