KR101133172B1 - A heading estimation system and the method of driving vehicle using magnet marker position - Google Patents

Abstract

PURPOSE: A driving vehicle absolute direction estimation system which uses an absolute position of a magnet marker and a method thereof are provided to estimate a vehicle direction on a real time basis using a magnet detection system installed on the vehicle and a magnet marker buried in a road. CONSTITUTION: A magnet detection sensor(110) is installed on a vehicle(100) in order to detect a plurality of magnet markers buried in a road. A changed direction detection sensor detects a changed direction of the vehicle between magnet marker detection time points. A controller estimates an absolute driving direction of the vehicle using the changed direction of the vehicle detected from the changed direction detection sensor and magnet information detected from the magnet detection sensor.

Description

A heading estimation system and the method of driving vehicle using magnet marker position}

The present invention relates to a system and method for estimating the absolute vehicle driving direction using the absolute position of the magnetic marker, more specifically, in real time to estimate the position of the vehicle using the magnetic marker embedded in the road and the magnetic detection system mounted on the vehicle. A system for estimating the orientation of a vehicle and such an estimation method.

Currently, a lot of research and development has been carried out at home and abroad for autonomous vehicles, and commercial vehicles are already operating.

Such autonomous vehicles are made by operating the steering wheel and controlling the speed instead of the former, and the autonomous vehicle must check the driving position of the vehicle in real time in order to follow the reference driving path without departing.

At this time, in order to measure the driving position of the autonomous vehicle, various kinds of position measuring systems including GPS, vision sys, and the like are used.

Typically, an electronic compass or gyroscope has been used to measure the driving direction of a conventional vehicle.

In this case, the electronic compass provides absolute orientation information based on the geomagnetism, and there is a problem in that it does not accumulate errors but reacts sensitively to the influence of an external interference magnetic field.

In the case of the gyroscope, the relative orientation information is given and a relatively accurate angle value can be obtained in a short time, but the relative error with the absolute orientation must be set, and the angle error accumulates over time. When driving in a straight line by the azimuth estimation method, the absolute azimuth angle of the vehicle is determined by using the detection position of the sensor and the buried position of the magnet based on the two detected magnetic markers. The absolute direction can be determined using the gyro sensor and the absolute direction error.

However, since the absolute direction can be determined only when the straight line condition and the vehicle satisfy the straight driving condition, if the time becomes longer until the next absolute direction initialization condition is satisfied, the bearing accumulation error over time, which is a fundamental problem of the gyro sensor, increases.

Accordingly, to solve these problems, an object of the present invention is to provide a driving vehicle absolute direction estimation system that can estimate the real-time absolute driving direction of the vehicle using a magnetic marker embedded in the road for vehicle location estimation and the like To provide an estimation method.

It is another object of the present invention to provide a system and method for estimating absolute vehicle direction using a magnetic marker absolute position, which can reduce the error of orientation measurement and reduce the system configuration cost for estimating the absolute direction of the vehicle by not using an additional direction sensor. It is.

The present invention to solve this technical problem;

A magnetic detection sensor mounted to the vehicle to detect a plurality of magnetic markers embedded in the road; A variable bearing detection sensor for detecting a vehicle change bearing between detection time points of the magnet markers; And a controller for estimating the absolute driving direction of the vehicle by using the vehicle fluctuation bearing between the magnet information detected by the magnet detecting sensor and the detection time of the magnet marker detected by the variable bearing detection sensor. It provides a vehicle vehicle absolute direction estimation system using.

In this case, the variable direction detection sensor is characterized in that the gyroscope.

In addition, the magnetic marker is characterized in that it is buried at intervals of 4m.

In addition, the controller; M0 (x0, y0) and m1 (x1, y1), which are absolute positions of the magnet marker m0 and magnet marker m1, and m0 (dy0) and m1 (dy1), which are the magnetic marker detection positions of the magnet sensor, The distance from the right end of the magnet sensor to the center of the magnet sensor (cr_y), the vehicle fluctuation azimuth (y_th) between the detection time of the magnetic marker, the movement distance of the sensor center between the detection time of the magnetic marker (MR1_x) and Using (MR1_y),

dc = sqrt (MR1_x ^ 2 + MR1_y ^ 2), th1 = atan (MR1_y / MR1_x), th4 = y_th-th1, MR2_x = dc * cos (th4), MR2_y = dc * sin (th4), cm_y = cr_y- dy0, cmy_y = cm_y * cos (y_th), hm0_y = cr_y- (MR2_y + cmy_y), A_y = hm0_y-dy1, cmy_x = cm_y * sin (y_th), A_x = MR2_x + cmy_x, Lm01 = sqrt ((x1-x0 ) ^ 2 + (y1-y0) ^ 2) to obtain the value;

o_th = asin (A_y / Lm01) = atan2 (A_y, A_x), m_th = atan2 [(y1-y0), (x1-x0)], and the orientation formed by the vertical orientation (o_th) and magnets (m0, m1) Find (m_th), then

The absolute azimuth angle (v_th) of the vehicle is calculated by substituting v_th = m_th-o_th.

At this time, the controller determines the azimuth error d_th of the gyro sensor using the vehicle absolute azimuth angle v_th, and the absolute azimuth angle is the azimuth error d_th at the vehicle absolute azimuth angle v_th until a new magnetic marker is detected. Characterized in that it is determined by subtracting.

The present invention also provides

A first step of receiving vehicle fluctuation angle information, which is a vehicle fluctuation azimuth, from a fluctuating direction detecting sensor when the vehicle is driving on a road where a magnet marker is embedded; When the magnet information is input from the magnet detection sensor, it checks the index of the magnet marker when the magnet information is input from the magnet detection sensor, determines the moving distance of the sensor center between the detection points of the magnet marker, and calculates the absolute azimuth angle of the vehicle. Determining azimuth error of the gyro sensor using the determined vehicle absolute azimuth angle; And after the second step, determining the absolute azimuth angle by subtracting an azimuth error from the vehicle absolute azimuth angle until a new magnetic marker is detected. The absolute direction of the driving vehicle using the absolute position of the magnetic marker An estimation method is also provided.

In this case, before the first step, a fourth step of setting various constants and initializing the variables may be further performed.

According to the present invention, in determining a vehicle absolute direction required for calculating a vehicle real-time driving position in a vehicle, in particular, an autonomous vehicle, the determination error of the azimuth angle is directly reflected in the vehicle position measurement error, thereby reducing the orientation measurement error and additionally expensive commercial orientation sensor. Since the system is not used, the system configuration cost for estimating the absolute direction of the driving vehicle can be reduced.

1 is a block diagram of a system for estimating an absolute direction of a traveling vehicle using an absolute position of a magnetic marker according to the present invention.
2 is a diagram illustrating a magnet marker installed on a road and a magnet detection sensor installed on a vehicle of the present invention.
3 is a diagram illustrating a plane movement trajectory of a magnet detecting sensor for estimating absolute direction of a driving vehicle using an absolute position of a magnetic marker according to the present invention.
4 is a control flowchart for estimating the absolute direction of a traveling vehicle using the magnetic marker absolute position according to the present invention.

With reference to the accompanying drawings, a vehicle vehicle absolute direction estimation system and method using a magnetic marker absolute position according to the present invention will be understood by the embodiments described in detail below.

1 to 3, the absolute vehicle vehicle direction estimation system using the magnetic marker absolute position according to the present invention is a magnet marker (m) embedded in the road (1) and the magnetic detection sensor 110 mounted on the vehicle 100 ) To estimate the real-time vehicle direction required for vehicle location estimation.

At this time, the position estimation based on the magnet marker (m) embedded in the road (1) can confirm the position only at the time of detecting the magnetic marker (m), but in order to control the vehicle 100 every time point required for control Each location requires magnetic location information of the vehicle 100.

Therefore, in order to estimate the vehicle position using the magnet marker m, the real time absolute driving direction of the vehicle 100 must be known.

In addition, the magnetic marker (m) is embedded in the road (1) at intervals of 4m.

At this time, if the interval of the magnetic marker (m) is less than 4m, the accuracy of the detection of the magnetic marker (m) can be more accurate, but the cost burden is large, if the interval of the magnetic marker (m) is more than 4m, the magnetic marker (m) ) As the reliability of detection decreases, it is possible to bury it by adjusting it at appropriate intervals if necessary.

The absolute vehicle vehicle direction estimation system using the absolute position of the magnetic marker according to the present invention is a magnetic detection sensor 110 mounted to the vehicle 100 to detect the magnetic marker (m) embedded in the road (1), Variable direction detection sensor 120 for detecting a vehicle azimuth direction between the detection time of the magnetic marker (m), the magnet information detected by the magnetic detection sensor 110 and the magnetic marker detected by the variable direction detection sensor 120 ( and a controller 130 for estimating the absolute driving direction of the vehicle 100 using the vehicle variation bearing between detection time points of m).

The controller 130 estimates the absolute driving direction of the vehicle 100 and uses the estimated position of the vehicle 100. At this time, the vehicle 100 is a self-driving vehicle.

The variable displacement detection sensor 120 uses a gyroscope. Of course, the variable displacement detection sensor 120 can be used to select a variety of sensors in addition to the gyroscope.

In order to estimate the absolute driving direction of the vehicle 100 according to the present invention, the absolute plane of the relationship between the magnetic marker m detected by the magnetic detection sensor 110 shown in FIG. Analyze with the plane movement trajectory indicated on the image.

In order to estimate the absolute driving direction of the vehicle 100, the magnetic detection sensor 110, which is first mounted on the vehicle, detects the magnetic marker m0 at time t0 and moves the space so that another magnetic marker (at time t1) is detected. m1) is detected.

In this case, the magnet detection sensor 110 may determine the absolute vehicle azimuth angle v_th when detecting the two magnets m0 and m1 in space-time.

In order to determine the vehicle absolute azimuth angle (v_th), the m0 (x0, y0) and m1 (x1, y1), which are absolute positions of the magnet marker m0 and the magnet marker m1, and the magnet marker of the magnet sensor 110 are detected. Between the positions m0 (dy0) and m1 (dy1), the distance from the right end of the magnet sensor 110 to the center of the magnet sensor 110 (cr_y), and the detection time of the magnetic markers (m0, m1) It is necessary to know (MR1_x) and (MR1_y) which are the moving distances of the sensor center between the vehicle fluctuation azimuth y_th and the detection points of the magnet markers m0 and m1.

At this time, m0 (x0, y0) and m1 (x1, y1), which are absolute positions of the magnet marker m0 and the magnet marker m1, are embedded with the magnet marker m on the road 1, and then precision such as GPS. It is measured and measured using a measuring instrument and made into a database.

In addition, the magnet markers m0 and m1 are detected by the detection positions dy0 and dy1 when the magnet detection sensors 110 pass through the magnet markers m0 and m1. Information output from.

In addition, the distance (cr_y) from the right end of the magnet sensor 110 to the center of the magnet sensor 110 is determined by the detection length and the installation position of the magnet sensor 110.

The vehicle variation direction y_th between the detection points of the magnet markers m0 and m1 is determined by detecting a magnet m1 based on the detection time t0 of the magnet m0 using a sensor such as a gyroscope ( The angle of change up to t1) can be measured.

In addition, the moving distances MR1_x and MR1_y of the sensor center between the detection points of the magnet markers m0 and m1 are accumulated between two detection points t0 and t1 of the magnet markers m0 and m1 using a vehicle kinematic model. You can get it by

The following equations (1) to (15) are performed using a plurality of pieces of information for determining the vehicle absolute azimuth angle v_th.

dc = sqrt (MR1_x ^ 2 + MR1_y ^ 2); (One)

th1 = atan (MR1_y / MR1_x); (2)

th4 = y_th-th1; (3)

MR2_x = dc * cos (th4); (4)

MR2_y = dc * sin (th4); (5)

cm_y = cr_y-dy0; (6)

cmy_y = cm_y * cos (y_th); (7)

hm0_y = cr_y- (MR2_y + cmy_y); (8)

A_y = hm0_y-dy1; (9)

cmy_x = cm_y * sin (y_th); 10

A_x = MR2_x + cmy_x; (11)

Lm01 = sqrt ((x1-x0) ^ 2 + (y1-y0) ^ 2); (12)

o_th = asin (A_y / Lm01) = atan2 (A_y, A_x); (13)

m_th = atan2 [(y1-y0), (x1-x0)]; (14)

v_th = m_th-o_th; (15)

In more detail, the vertical direction (o_th) is obtained by substituting the value calculated through Equation (1) to Equation (12) into Equation (13), and using Equation (14), magnets m0 and m1. This direction (m_th) is obtained.

Then, the absolute azimuth angle of the vehicle 100 by substituting the vertical direction o_th obtained through the equation (13) into the equation (15) in the orientation m_th obtained by the magnets m0 and m1 obtained through the equation (14). Compute (v_th).

When the vehicle absolute azimuth angle v_th is determined, the azimuth error d_th of the gyro sensor may be determined using the vehicle azimuth angle. The absolute azimuth angle is then the azimuth error d_th from the vehicle absolute azimuth angle v_th until a new magnetic marker is detected again. Determine by subtracting).

Hereinafter, a process of estimating an absolute direction of a driving vehicle using an absolute position of a magnet marker according to the present invention will be described with reference to FIGS. 1 to 4.

In order to estimate the absolute vehicle azimuth for estimating the position of the vehicle 100, the controller 130 of the vehicle 100 detects the magnet when the vehicle 100 travels on the road 1 in which the magnetic marker m is embedded. The absolute driving azimuth angle is estimated by receiving the magnet information from the sensor 110 and the vehicle azimuth bearing information between the detection time points of the magnetic markers m from the variable bearing detection sensor 120.

That is, the controller 130 has a distance (cr_y) from the right end of the magnet sensor 110 to the center of the magnet sensor 110, m0 which is the absolute position of the magnet marker (m0) and the magnet marker (m1) (x0, y0) and m1 (x1, y1) are embedded in a variety of constants, such as embedding a magnetic marker (m) on the road (1) and then measuring them using a precision measuring instrument such as GPS to make a database. Initialize the settings and variables (S100).

After performing step S100, the controller 130 receives vehicle change angle information, which is a vehicle change bearing direction, from the change direction detection sensor 120.

Then, it is monitored whether magnet information is input from the magnet detection sensor 110. (S120)

When the magnet information is input from the magnet detection sensor 110 through the step S120, the index of the magnet marker is checked, and (MR1_x) and (MR1_y), which are the moving distances of the sensor centers between the detection points of the magnet marker m, are determined. After the determination, the vehicle absolute azimuth angle v_th is calculated by performing equations (1) to (15), and the azimuth error d_th of the gyro sensor is determined using the determined vehicle absolute azimuth angle v_th (S130).

The absolute azimuth angle is determined by subtracting the azimuth error d_th from the vehicle absolute azimuth angle v_th until the new magnetic marker m is detected again through the step S130.

Although the preferred embodiment of the present invention has been described above, the scope of the present invention is not limited thereto, and the scope of the present invention extends to the scope of the present invention to be substantially equivalent to the embodiment of the present invention. Various modifications can be made by those skilled in the art without departing from the scope of the present invention.

1: road m, m0, m1: magnetic marker
100: vehicle 110: magnetic detection sensor
120: variable direction detection sensor 130: controller

Claims (7)

A magnetic detection sensor mounted to the vehicle to detect a plurality of magnetic markers embedded in the road;
A variable bearing detection sensor for detecting a vehicle change bearing between detection time points of the magnet markers;
And a controller for estimating the absolute driving azimuth of the vehicle by using the vehicle azimuth bearing between the magnet information detected by the magnet detecting sensor and the detection time of the magnet marker detected by the variable bearing detection sensor.
The controller,
M0 (x0, y0) and m1 (x1, y1), which are absolute positions of the magnet marker m0 and magnet marker m1, and m0 (dy0) and m1 (dy1), which are the magnetic marker detection positions of the magnet sensor, The distance from the right end of the magnet sensor to the center of the magnet sensor (cr_y), the vehicle fluctuation azimuth (y_th) between the detection time of the magnetic marker, the movement distance of the sensor center between the detection time of the magnetic marker (MR1_x) and Using (MR1_y),
dc = sqrt (MR1_x ^ 2 + MR1_y ^ 2);
th1 = atan (MR1_y / MR1_x);
th4 = y_th-th1;
MR2_x = dc * cos (th4);
MR2_y = dc * sin (th4);
cm_y = cr_y-dy0;
cmy_y = cm_y * cos (y_th);
hm0_y = cr_y- (MR2_y + cmy_y);
A_y = hm0_y-dy1;
cmy_x = cm_y * sin (y_th);
A_x = MR2_x + cmy_x;
Lm01 = sqrt ((x1-x0) ^ 2 + (y1-y0) ^ 2);
o_th = asin (A_y / Lm01) = atan2 (A_y, A_x);
Substituting m_th = atan2 [(y1-y0), (x1-x0)]; to find the azimuth (m_th) between the vertical orientation (o_th) and the magnets (m0, m1),
The absolute vehicle bearing direction estimation system using the magnetic marker absolute position, characterized in that to calculate the absolute bearing angle (v_th) of the vehicle by substituting v_th = m_th-o_th ;.
The method of claim 1,
The absolute direction estimation system for a vehicle using the magnetic marker absolute position, characterized in that the variable position detection sensor is a gyroscope.
The method of claim 1,
The magnetic marker is a vehicle vehicle absolute direction estimation system using the absolute position of the magnetic marker, characterized in that embedded in the road at intervals of 4m.
delete The method of claim 1,
The controller determines the azimuth error d_th of the gyro sensor using the vehicle absolute azimuth angle v_th, and the absolute azimuth angle subtracts the azimuth error d_th from the vehicle absolute azimuth angle v_th until a new magnetic marker is detected. Travel vehicle absolute direction estimation system using the absolute position of the magnetic marker, characterized in that determined as one.
A change angle information input step of receiving vehicle change angle information, which is a vehicle change bearing, from a change direction detection sensor when the vehicle travels on a road on which the magnetic marker is embedded;
A monitoring step of monitoring whether magnetic information is input from a magnet detecting sensor;
An absolute azimuth calculation step of checking an index of the magnet marker when the magnet information is input from the magnet detection sensor, determining a moving distance of the sensor center between detection points of the magnet marker, and calculating the absolute vehicle azimuth angle;
Azimuth error determination step of determining azimuth error of the gyro sensor using the determined vehicle absolute azimuth angle, and
After determining the azimuth error, the absolute azimuth angle determining step of determining the absolute azimuth angle by subtracting the azimuth error from the vehicle absolute azimuth angle until a new magnetic marker is detected, the absolute direction of the driving vehicle using the absolute position of the magnetic marker Estimation method.
The method of claim 6,
Prior to the step of inputting the variable angle information, an initialization step of initializing the constants and the setting of the constants including the distance from the right end of the magnet sensor to the center of the magnet sensor and the absolute position of the magnet marker; A method for estimating absolute direction of a vehicle using magnetic marker absolute position.

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