JP2011112591A - Apparatus for loading mobile body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for loading a mobile body which can accurately obtain an angular velocity around a shaft different from a certain shaft when the angular velocity generates around the shaft of the mobile body due to movement of the mobile body without depending on a mounted state to the mobile body. <P>SOLUTION: The apparatus for loading the mobile body includes: a mounting angle calculation part 183 for calculating an angle making a pitch axis of a gyro sensor 132 and a vertical shaft of a vehicle body on the basis of gravity acceleration output with a gravity acceleration calculation part 181 and vehicle body acceleration output with a vehicle body acceleration calculation part 182; and a correction part 133 for subtracting an unnecessary component calculated from the angular velocity around the pitch axis detected with the gyro sensor 132 by calculating the unnecessary component included in the angular velocity around the pitch axis detected with the gyro sensor 132 on the basis of the angular velocity around a yaw axis detected with the gyro sensor 132 and the angle calculated with the mounting angle calculation part 183. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a mobile unit mounting device that can be mounted on a mobile unit, and more particularly to a mobile unit mounting device that is installed in a vehicle or the like and used as a navigation device.

  In recent years, a simple navigation device called PND (Portable Navigation Device) that is portable by simplifying functions and reducing the size and weight of the main body of the navigation device has become widespread.

  In addition to receiving GPS signals and detecting the current position of the PND, the PND has a built-in acceleration sensor and gyro sensor as an auxiliary means for cases where the GPS signal cannot be acquired. It is possible to detect the position.

  As a self-contained navigation type conventional technique for estimating the current position of a vehicle using this type of sensor, for example, Patent Document 1 discloses. In this Patent Document 1, the first speed detected by the acceleration sensor attached in parallel to the traveling direction of the moving body and the acceleration sensor attached at a predetermined angle with respect to the traveling direction of the moving body are detected. Based on the second acceleration, it is possible to accurately calculate the inclination angle when the moving body travels on the slope.

By the way, since the PND can be easily attached to and detached from the dashboard in the vehicle, the attaching work is performed by the user himself. However, if the acceleration sensor or gyro sensor used in the self-contained navigation system is not mounted in the correct posture so as to face a predetermined direction, the current position cannot be accurately detected due to errors caused by the respective mounting angles. There was a problem.

  Therefore, the applicant of the present application has proposed the following navigation device in the patent application of Japanese Patent Application No. 2009-189844.

  In this navigation device, the gravitational acceleration is calculated based on the output signal output from the acceleration sensor while the vehicle is stopped, and the vehicle body acceleration is calculated based on the output signal output from the acceleration sensor while the vehicle is traveling straight ahead. An attachment angle of the navigation device with respect to the vehicle is calculated based on the gravitational acceleration and the vehicle body acceleration. This makes it possible to accurately calculate the attachment angle of the navigation device regardless of the attachment angle of the acceleration sensor.

Japanese Patent Laid-Open No. 9-101141 (paragraphs 0019 to 0026, FIG. 1)

  In the above Japanese Patent Application No. 2009-189848, the angle formed by the Y axis (horizontal axis) of the vehicle and the Y axis (horizontal axis) of the navigation apparatus can be calculated. Therefore, the correction constant obtained from the calculated angle. Can be used to correct the pitch axis output of the gyro sensor.

  However, when the vehicle travels on a curved road surface, an angular velocity is generated around the vehicle's yaw axis (vertical direction axis), and the vehicle's Z axis (vertical direction axis) and the navigation device's Y axis (horizontal direction) depend on the installation state of the navigation device. When the direction axis is not orthogonal, an unnecessary component due to the angular velocity around the yaw axis of the vehicle is included in the pitch axis output of the gyro sensor. In the above Japanese Patent Application No. 2009-189884, this unnecessary component is not taken into consideration, and therefore the accuracy may deteriorate even if the above correction is performed.

  In the present invention, when an angular velocity is generated around a certain axis of the moving body due to the movement of the moving body, it is possible to accurately obtain an angular velocity around an axis different from the axis regardless of the state of attachment to the moving body. An object is to provide a mobile device mounted device.

In order to achieve the above object, the present invention provides:
A mobile unit mounting device mounted on a mobile unit,
An acceleration detection unit for detecting acceleration in three axis directions;
An angular velocity detector that detects angular velocities about the first axis and the second axis;
An output signal output from the acceleration detection unit when the moving body is in a stopped state, and an output signal output from the acceleration detection unit when the moving body is moving straight ahead by acceleration or deceleration And an angle calculation unit that calculates an angle formed by the first axis and an axis corresponding to the second axis of the movable body,
An unnecessary component included in the angular velocity around the first axis detected by the angular velocity detector based on the angular velocity around the second axis detected by the angular velocity detector and the angle calculated by the angle calculator. An unnecessary component calculation unit to calculate,
An unnecessary component removing unit that subtracts the unnecessary component calculated by the unnecessary component calculating unit from the angular velocity around the first axis detected by the angular velocity detecting unit;
It is set as the structure provided with.

  According to such a configuration, the angular velocity detection is performed when an angular velocity is generated around the axis corresponding to the second axis of the movable body due to the movement of the movable body, regardless of the state of attachment of the device mounted on the movable body to the movable body. The unnecessary component included in the angular velocity around the first axis detected by the unit is calculated, and the unnecessary component calculated from the angular velocity around the first axis detected by the angular velocity detection unit is removed. An angular velocity around the axis corresponding to the axis can be obtained with high accuracy.

  In the above configuration, for example, the first axis may be a horizontal axis (pitch axis), and the second axis may be a vertical axis (yaw axis).

  As a result, the angular velocity around the horizontal axis of the moving body can be obtained with high accuracy when the moving body generates an angular velocity around the vertical axis of the moving body regardless of the state of attachment of the device mounted on the moving body. It becomes possible.

Further, in any one of the configurations described above, an output signal output from the acceleration detection unit when the moving body is in a stopped state, and a state in which the moving body is moving straight ahead by acceleration or deceleration. A second angle calculation unit that calculates an angle between the second axis and an axis corresponding to the second axis of the movable body based on an output signal output from the acceleration detection unit;
The unnecessary component calculation unit corrects the angular velocity around the second axis detected by the angular velocity detection unit based on the angle calculated by the second angle calculation unit, and calculates the correction result and the angle calculation unit. An unnecessary component may be calculated based on the angle.

  According to such a configuration, it is possible to accurately obtain an angular velocity around the axis corresponding to the second axis of the moving body by the correction, and as a result, it is possible to improve the accuracy of the calculated unnecessary component.

  Moreover, it is preferable that the mobile body mounting device having any one of the above configurations is, for example, a portable in-vehicle navigation device. Since the portable in-vehicle navigation device is attached to the vehicle by the user himself, the attachment tends to be inaccurate. However, according to the present invention, when an angular velocity is generated around the axis corresponding to the second axis of the vehicle due to the movement of the vehicle, the axis around the axis corresponding to the first axis of the vehicle, regardless of the state of attachment to the vehicle. The angular velocity can be obtained with high accuracy.

  According to the mobile body mounting device of the present invention, when an angular velocity is generated around a certain axis of the mobile body due to the movement of the mobile body, regardless of the attachment state to the mobile body, The angular velocity can be obtained with high accuracy.

It is a block diagram which shows the structure of the navigation apparatus which concerns on embodiment of this invention. It is a flowchart regarding the gravity acceleration calculation process which concerns on embodiment of this invention. It is a flowchart regarding the vehicle body acceleration calculation process which concerns on embodiment of this invention. It is a flowchart regarding the attachment angle calculation process which concerns on embodiment of this invention. It is a figure which shows an example of the attachment state to the vehicle body of a navigation apparatus. It is a figure explaining the Y-axis (horizontal axis) and Z-axis (vertical axis) of a vehicle body. It is a figure explaining the relationship between the Xa axis | shaft of an acceleration sensor, and the 3 axis | shafts of a vehicle body. It is a flowchart regarding the process which calculates the angular velocity about the yaw axis and pitch axis of the vehicle body which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiment described below exemplifies a navigation device mounted on a vehicle as a mobile body mounting device for embodying the technical idea of the present invention, and the present invention is specified to this navigation device. However, the present invention is equally applicable to the mobile device mounted in other embodiments included in the technical idea shown in the claims. Note that a portable PND is suitable as the navigation device.

  First, the configuration of the navigation device according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a navigation device according to an embodiment of the present invention.

  The navigation device 10 includes a control unit 100, a communication unit 110, a GPS positioning unit 120, a self-contained navigation positioning unit 130, a route search unit 140, a route guidance unit 150, a display unit 160, an input unit 170, a calculation unit 180, and a storage unit 190. It is prepared for.

  The control unit 100 includes a processor including a CPU 100a, a RAM 100b, and a ROM 100c. The CPU 100a executes a program stored in the RAM 100b or the ROM 100c to control and control the operation of each unit of the navigation device 10. In addition, the control unit 100 determines that the vehicle body on which the navigation device 10 is mounted is stopped or is traveling straight ahead by acceleration based on signals from an acceleration sensor 131 and a gyro sensor 132 described later.

  The communication unit 110 transmits and receives various types of information such as map data to and from an information providing server (not shown) that can communicate with the navigation device 10 under the control of the control unit 100.

  The GPS positioning unit 120 receives radio waves including time information from a plurality of GPS satellites orbiting over the earth, and calculates current position information of the vehicle body on which the navigation device 10 is mounted based on the received radio waves. .

  The self-contained navigation positioning unit 130 includes an acceleration sensor 131 and a gyro sensor 132.

  When the acceleration sensor 131 is installed in a correct posture with respect to the vehicle body, the acceleration sensor 131 causes the acceleration in the vehicle traveling direction (X-axis direction) and the vehicle body horizontal direction (Y-axis direction). The acceleration and the acceleration in the vertical direction (Z-axis direction) of the vehicle body are detected.

  When the gyro sensor 132 is installed in a correct posture with respect to the vehicle body, the gyro sensor 132 rotates the vehicle body around the Y axis (pitch axis) and the angular velocity when the vehicle body rotates around the Y axis (pitch axis). The angular velocity when detecting is detected.

  In addition, the self-contained navigation positioning unit 130 corrects a deviation between the axes of the vehicle body and the acceleration sensor 131 that occurs when the navigation device 10 is not installed in a correct posture with respect to the vehicle body, and corrects an output from the gyro sensor 132. A correction unit 133 is provided. The correction process by the correction unit 133 will be described in detail later.

  When the departure point and the destination point are designated by the operation of the input unit 170, the route search unit 140 refers to the road data stored in the map storage unit 192 of the storage unit 190, and reaches the destination point from the departure point. The guide route is searched and guide route data is created. The guidance route searched by the route search unit 140 is displayed on the display unit 160 together with the map image around the current position by the control unit 100, and used for guidance to the destination point.

  The route guidance unit 150 compares the guidance route data searched by the route search unit 140 with the current position detected by the GPS positioning unit 120, and outputs the guidance required at the current position from a speaker or the like (not shown). To do.

  The display unit 160 is a display unit having a display screen composed of a display panel such as an LCD, and displays a map image, a guide route, a current position, and the like.

  The input unit 170 is configured by operation buttons, a touch panel, and the like, and operates various functions of the navigation device 10 and inputs necessary numerical values and characters.

  The calculation unit 180 includes a gravitational acceleration calculation unit 181, a vehicle body acceleration calculation unit 182, and an attachment angle calculation unit 183. The calculation process by each unit will be described in detail later.

  The storage unit 190 includes an attachment angle storage unit 191 and a map storage unit 192. The attachment angle storage unit 191 stores the angles formed by the three axes of the vehicle body and the three axes of the acceleration sensor calculated by the attachment angle calculation unit 183.

  The map storage unit 192 stores road node data including road node data and road link data in which nodes such as intersections and branch points of the roads are nodes and routes connecting the nodes are links. The road node data includes road node numbers, position coordinates, the number of connection links, intersection names, and the like. The road link data includes the number of road nodes as starting and ending points, road type, link length (link cost), required time, number of lanes, road width, and the like. Further, data such as bridges, tunnels, railroad crossings, and toll gates are added to the road link data as link attributes. The road type is information including a distinction between an expressway and a toll road and a distinction such as a national road or a prefectural road.

  In addition to road data, the map storage unit 192 may include background image data stored in a vector format so that a map image can be easily displayed. When the navigation device 10 is used by the control unit 100, the map image data including the road data and the background image data is extracted from the map storage unit 192 and a predetermined range including the current position of the navigation device 10 is shown. The current position mark and the guide route image are superimposed on each other and displayed on the display unit 160.

  Next, gravity acceleration and vehicle body acceleration calculation processing in the navigation device 10 according to the present invention will be described with reference to the flowcharts shown in FIGS. The vehicle body acceleration is the acceleration of the vehicle including gravitational acceleration.

  First, in step S21, the control unit 100 determines whether or not the vehicle on which the navigation device 10 is mounted is stopped based on signals from the acceleration sensor 131 and the gyro sensor 132. (N of step S21), the process of step S21 is repeated until it stops.

  If it is determined that the vehicle is stopped (Y in step S21), the process proceeds to step S22, and the acceleration detected by the gravitational acceleration calculating unit 181 from the acceleration sensor 131 every 0.1 s is controlled by the control unit 100. (That is, gravitational acceleration) is buffered in the buffer 181a.

  Then, in step S23, the gravitational acceleration calculation unit 181 determines whether or not the number of buffered acceleration samples has reached a predetermined number of 10 and if not (N in step S23), Returning to step S22, on the other hand, if the predetermined number is reached (Y in step S23), the process proceeds to step S24. Note that the predetermined number of samples is not particularly limited to ten.

  In step S24, the gravitational acceleration calculation unit 181 calculates an average gravitational acceleration value by averaging the 10 accelerations buffered in the buffer 181a, and the calculated gravitational acceleration average value is calculated by the gravitational acceleration calculation unit. The gravity acceleration calculated in 181 is output to the attachment angle calculation unit 183, and the process proceeds to step S25. In step S25, the gravitational acceleration calculation unit 181 clears the buffer 181a, and the process proceeds to step S31 (FIG. 3).

  In step S31, the control unit 100 determines whether or not the vehicle equipped with the navigation device 10 is traveling straight ahead by acceleration based on signals from the acceleration sensor 131 and the gyro sensor 132, and the vehicle is traveling straight ahead by acceleration. If it is determined that (Yes in Step S31), the process proceeds to Step S32.

  In step S32, under the control of the control unit 100, the vehicle body acceleration calculation unit 182 buffers the acceleration detected from the acceleration sensor 131 every 0.1 s in the buffer 182a.

  Then, in step S33, the vehicle body acceleration calculation unit 182 determines whether or not the number of buffered acceleration samples has reached a predetermined value of 10 (N in step S33). Returning to step S31, on the other hand, if the predetermined number is reached (Y in step S33), the process proceeds to step S34.

  In step S34, the vehicle body acceleration calculation unit 182 calculates an average vehicle body acceleration value by arithmetically averaging the 10 accelerations buffered in the buffer 182a, and the vehicle body acceleration calculation unit calculates the calculated vehicle body acceleration average value. The vehicle body acceleration calculated in 182 is output to the attachment angle calculation unit 183, and the processing is completed (END).

  If it is determined in step S31 that the vehicle is not traveling straight ahead (N in step S31), the process proceeds to step S35, and the vehicle body acceleration calculation unit 182 determines whether or not the vehicle is buffering. If buffering is in progress (Y in step S35), the process proceeds to step S36, where the vehicle body angular velocity calculation unit 182 clears the buffer 182a and returns to step S21 (FIG. 2). On the other hand, if buffering is not in progress (N in step S35), the process returns to step S21 (FIG. 2).

  Note that the average value may be calculated by buffering acceleration during straight traveling while decelerating instead of during straight traveling by acceleration.

  Next, an attachment angle calculation process of the navigation device 10 with respect to the vehicle body will be described.

The mounting angle calculation unit 183 includes a gravity acceleration A _{G *} (A _GX , A _GY , A _GZ ) output from the gravity acceleration calculation unit 181 and a vehicle body acceleration A _{GD *} (A _GDX , output from the vehicle body acceleration calculation unit 182. Based on (A _GDY , A _GDZ ), the attachment angle of the navigation device 10 with respect to the vehicle body is calculated.

That is, as shown in FIG. 5, the three orthogonal axes of the vehicle body 20 are the X axis, the Y axis, and the Z axis (where the X axis is the same axis as the traveling direction of the vehicle body, the Y axis is the horizontal axis of the vehicle body, Z Assuming that the axis is the vertical axis of the vehicle body and the acceleration sensor 131 is arranged on the Xa axis, Ya axis, and Za axis that are orthogonal to each other of the navigation device 10, the mounting angle calculation unit 183 The deviation (angle θ _* ) of each axis between the X axis, the Y axis, and the Z axis) and the three axes (Xa axis, Ya axis, Za axis) of the acceleration sensor 131 is calculated.

Here, as shown in FIG.
The angle between the X axis and the Xa axis is θxax,
The angle formed by the X axis and the Ya axis is θyax,
The angle between the X axis and the Za axis is θzax,
And Similarly,
The angle between the Y axis and the Xa axis is θxay,
The angle between the Y axis and the Ya axis is θyay,
The angle between the Y axis and the Za axis is θzay,
age,
The angle between the Z axis and the Xa axis is θxaz,
The angle between the Z axis and the Ya axis is θyaz,
The angle formed by the Z axis and the Za axis is θzaz,
And Then, each θ _* is calculated according to the procedure described below.

First, since the X axis of the three axes of the vehicle body 20 is the same axis as the traveling direction of the vehicle body as shown in FIG. 5, the direction vector X of this X axis is the motion when the vehicle is accelerating. Parallel to the target acceleration _{AD *} . For this reason, the direction vector X of the X axis is detected by the acceleration sensor 131 when the acceleration sensor 131 detects the gravitational acceleration _{AG *} detected by the acceleration sensor 131 when the vehicle is stopped. Based on the vehicle body acceleration A _{GD *} , the following expression (3) is expressed.

X = A _{D *} = A _{GD *} −A _{G *} (3)
here,
A _{G *} = (A _GX , A _GY , A _GZ )
A _{GD *} = (A _GDX , A _GDY , A _GDZ )
Therefore, if X = (Xx, Xy, Xz),
Xx = A _GDX -A _GX
Xy = A _GDY -A _GY
Xz = A _GDZ -A _GZ
It becomes.

Next, as shown in FIG. 6A, the Y-axis of the vehicle body 20 is a vector perpendicular to a plane including two vectors of the vehicle acceleration A _{GD *} and the gravity acceleration A _{G *} , so this normal vector Y is expressed as the following product (4) as an outer product of vectors.

Y = A _{G *} × A _{GD *} (4)
Here, if Y = (Yx, Yy, Yz),
Yx = A _GY・ A _GDZ −A _GDY・ A _GZ
Yy = A _GZ / A _GDX- A _GDZ / A _GX
Yz = A _GX・ A _GDY −A _GDX・ A _GY
It becomes.

  Further, as shown in FIG. 6B, the Z axis of the vehicle body 20 becomes a vector perpendicular to a plane including the two vectors of the X axis and the Y axis of the vehicle body obtained as described above. Is expressed by the following equation (5) as an outer product of vectors.

Z = X × Y (5)
Here, if Z = (Zx, Zy, Zz),
Zx = Xy.Yz-Yy.Xz
Zy = Xz.Yx-Yz.Xx
Zz = Xx.Yy-Yx.Xy
It becomes.

In this way, when the three axes (X axis, Y axis, Z axis) of the vehicle body 20 are calculated, the angles formed with the three axes (Xa axis, Ya axis, Za axis) of the acceleration sensor 131 are obtained. Here, an angle formed by two vectors of A = (Ax, Ay, Az) and B = (Bx, By, Bz) is obtained by using the cosine theorem.
A · B = | A || B | cos θ
Than,
θ = cos ⁻¹ {A · B / (| A || B |)}
Can be obtained as However,
A ・ B = AxBx + AyBy + AzBz
| A | = √ (Ax ² + Ay ² + Az ² )
| B | = √ (Bx ² + By ² + Bz ² )
Is established.

  Therefore, for example, the angle θxax formed by the X axis of the vehicle body 20 and the Xa axis of the acceleration sensor 131 is expressed by the following equation (6).

θxax = cos ⁻¹ {X · Xa / (| X || Xa |)} (6)
here,
X = (Xx, Xy, Xz), Xa = (a, 0, 0) However, since a is an arbitrary constant, Equation (6) is
θxax = cos ⁻¹ {Xx / √ (Xx ² + Xy ² + Xz ² )} (7)
It becomes. However,
Xx = A _GDX -A _GX
Xy = A _GDY -A _GY
Xz = A _GDZ -A _GZ
Therefore, the angle θx formed by the Y axis and Z axis of the vehicle body 20 and the Xa axis of the acceleration sensor 131
ay and θxaz are respectively
^{θxay = cos -1 {Yx / √} (Yx 2 + Yy 2 + Yz 2)} ··· (8)
θxaz = cos ⁻¹ {Zx / √ (Zx ² + Zy ² + Zz ² )} (9)
It becomes.

In addition, an angle θyay between the Y axis of the vehicle body 20 and the Ya axis of the acceleration sensor 131 is
Y = (Yx, Yy, Yz), Ya = (0, b, 0) However, since b is an arbitrary constant, it is expressed by the following equation (10).

^{θyay = cos -1 {Yy / √} (Yx 2 + Yy 2 + Yz 2)} ··· (10)
Similarly, angles θyaz and θyax formed by the Z-axis and X-axis of the vehicle body 20 and the Ya-axis of the acceleration sensor 131 are respectively
^{θyaz = cos -1 {Yz / √} (Yx 2 + Yy 2 + Yz 2)} ··· (11)
^{θyax = cos -1 {Yx / √} (Yx 2 + Yy 2 + Yz 2)} ··· (12)
It becomes. However,
Yx = A _GY・ A _GDZ −A _GDY・ A _GZ
Yy = A _GZ / A _GDX- A _GDZ / A _GX
Yz = A _GX・ A _GDY −A _GDX・ A _GY
Furthermore, an angle θzaz formed between the Z axis of the vehicle body 20 and the Za axis of the acceleration sensor 131 is
Z = (Zx, Zy, Zz), Ya = (0, 0, c) However, since c is an arbitrary constant, it is expressed by the following equation (13).

θzaz = cos ⁻¹ {Zz / √ (Zx ² + Zy ² + Zz ² )} (13)
Similarly, the angles θzax and θzay formed by the X axis and Y axis of the vehicle body 20 and the Za axis of the acceleration sensor 131 are respectively
θzax = cos ⁻¹ {Zx / √ (Zx ² + Zy ² + Zz ² )} (14)
θzay = cos ⁻¹ {Zy / √ (Zx ² + Zy ² + Zz ² )} (15)
It becomes. However,
Zx = Xy.Yz-Yy.Xz
= (A _GDY -A _GY ) ・ (A _GX・ A _GDY -A _GDX・ A _GY )
-(A _GZ · A _GDX- A _GDZ · A _GX ) · (A _GDZ- A _GZ )
Zy = Xz.Yx-Yz.Xx
= (A _GDZ -A _GZ ) ・ (A _GY・ A _GDZ -A _GDY・ A _GZ )
-(A _GX · A _GDY- A _GDX · A _GY ) · (A _GDX- A _GX )
Zz = Xx.Yy-Yx.Xy
= (A _GDX -A _GX ) ・ (A _GZ・ A _GDX -A _GDZ・ A _GX )
-(A _GY · A _GDZ- A _GDY · A _GZ ) · (A _GDY- A _GY )
In this way, the angle (deviation angle) θ formed by each axis between the three axes (X axis, Y axis, Z axis) of the vehicle body 20 and the three axes (Xa axis, Ya axis, Za axis) of the acceleration sensor 131. _* Is the gravity acceleration A _{G *} = (A _GX , A _GY , A _GZ ) output from the gravity acceleration calculation unit 181 by the mounting angle calculation unit 183 and the vehicle body acceleration A _GD output from the vehicle body acceleration calculation unit 182 _* = Calculated from (A _GDX , A _GDY , A _GDZ ).

  FIG. 4 shows a flowchart relating to the attachment angle calculation process for the vehicle body of the navigation device 10 by the attachment angle calculation unit 183.

  First, in step S41, the attachment angle calculation unit 183 determines whether or not the gravitational acceleration calculated from the gravitational acceleration calculation unit 181 and the vehicle body acceleration calculated from the vehicle body acceleration calculation unit 182 are input. Step S41 is repeated until both are input.

When the gravitational acceleration and the vehicle body acceleration are input (Y in step S41), in step S42, the attachment angle calculation unit 183 advances the vehicle based on the input gravitational acceleration A _{G *} and the vehicle body acceleration A _{GD *.} A vector X that is the X axis of the vehicle body parallel to the direction is calculated.

Then, the process proceeds to step S43, where the attachment angle calculation unit 183 is based on the input gravitational acceleration A _{G *} and the vehicle acceleration A _{GD *} , and a normal vector that becomes the Y axis of the vehicle body perpendicular to the plane including these two vectors. Y is calculated.

  Further, in step S44, the attachment angle calculation unit 183 calculates a normal vector Z that is the Z axis of the vehicle body perpendicular to the plane including the two vectors, based on the calculated vector X and vector Y.

In step S45, the attachment angle calculation unit 183 determines each axis between the three axes (X axis, Y axis, Z axis) of the vehicle body and the three axes (Xa axis, Ya axis, Za axis) of the acceleration sensor 131. angle of calculating the (deviation angle) theta _*, and stores the calculated shift angle theta _* the mounting angle storage unit 191. The deviation angle θ _* stored in the attachment angle storage unit 191 is used for correction when the correction unit 133 converts the output from the three axes of the acceleration sensor 131 into the three-axis output of the vehicle body.

Here, correction for converting the three-axis output of the acceleration sensor 131 into the three axes of the vehicle body 20 will be described. For example, as shown in FIG. 7, assuming that there is an acceleration of Xa only on the Xa axis of the acceleration sensor 131,
X = Xa · cos θxax, Y = Xa · cos θxay, Z = Xa · cos θxaz
Can be expressed as

Similarly, when there is an acceleration of Ya only on the Ya axis and Za only on the Za axis,
X = Ya · cos θ yax, Y = Ya · cos θ yay, Z = Ya · cos θ yaz
X = Za · cos θzax, Y = Za · cos θzay, Z = Za · cos θzaz
Therefore, based on the angles θ * formed by the three axes of the vehicle body 20 and the three axes of the acceleration sensor 131 stored in the attachment angle storage unit 191, an acceleration of A = (Xa, Ya, Za) is detected by the acceleration sensor 131. If detected, the acceleration (X, Y, Z) in the three-axis direction of the vehicle body is X = Xa · cos θxax + Ya · cos θyax + Za · cos θzax
Y = Xa · cos θxay + Ya · cos θyay + Za · cos θzay
Z = Xa · cos θxaz + Ya · cos θ yaz + Za · cos θzaz
It is expressed as

This can be organized as shown in the following equation (16), and since the acceleration sensor 131 can be converted from the three axes of the acceleration sensor 131 to the three axes of the vehicle body, the deviation of the mounting angle can be corrected.

  Further, the correction unit 133 corrects an output error from the gyro sensor 132 that occurs when the navigation device 10 is not installed in a correct posture with respect to the vehicle body. This will be described with reference to the flowchart shown in FIG.

Here, if the angle between the Z axis of the vehicle body and the vertical axis (yaw axis) of the gyro sensor 132 is θzAve, the correction constant Jy of the yaw axis output of the gyro sensor 132 is
Jy = 1 / cos | θzAve |
It is expressed as Here, since it can be said that θzAve is θzaz, the correction unit 133 calculates the correction constant Jy based on θzaz stored in the attachment angle calculation unit 191 (step S81). Then, the correction unit 133 multiplies the yaw axis output of the gyro sensor 132 by the correction constant Jy to calculate the angular velocity ωy around the yaw axis of the vehicle body (step S82).

  If the angle formed between the Z axis of the vehicle body and the horizontal axis (pitch axis) of the gyro sensor 132 is θzp, an unnecessary component represented by ωy × cos θzp is generated by the gyro sensor 132 due to the angular velocity ωy around the yaw axis of the vehicle body. It will be included in the pitch axis output. Since θzp can be said to be θyaz, the correction unit 133 calculates an unnecessary component based on the calculated ωy and θyaz stored in the attachment angle calculation unit 191 (step S83). Then, the correction unit 133 subtracts the unnecessary component calculated from the pitch axis output of the gyro sensor 132 to remove the unnecessary component (step S84).

Here, if the angle between the Y axis of the vehicle body and the horizontal axis (pitch axis) of the gyro sensor 132 is θyAve, the correction constant Jp of the pitch axis output of the gyro sensor 132 is
Jp = 1 / cos | θyAve |
It is expressed as Here, since it can be said that θyAve is θyay, the correction unit 133 calculates the correction constant Jp based on θyay stored in the attachment angle calculation unit 191 (step S85). Then, the correction unit 133 multiplies the subtraction result of the unnecessary component by the calculated correction constant Jp to calculate the angular velocity ωp around the pitch axis of the vehicle body (step S86).

  The angular velocity ωp around the pitch axis of the vehicle body calculated in this way is the vehicle traveling on a curved road surface when the angle θzp formed by the Z axis of the vehicle body and the horizontal axis (pitch axis) of the gyro sensor 132 is not 90 degrees. This is calculated in consideration of unnecessary components that appear when the angular velocity around the yaw axis of the vehicle body is generated.

  Thereby, for example, when the control unit 100 determines whether the vehicle is traveling on the upper highway or the lower general road based on the angular velocity ωp around the pitch axis of the vehicle body output from the correction unit 133. In addition, the determination accuracy can be improved.

  As mentioned above, although embodiment of this invention was described, if it is in the range of the meaning of this invention, embodiment can be variously changed.

DESCRIPTION OF SYMBOLS 10 Navigation apparatus 100 Control part 110 Communication part 120 GPS positioning part 130 Autonomous navigation positioning part 131 Acceleration sensor 132 Gyro sensor 133 Correction | amendment part 140 Path | route search part 150 Path | route guidance part 160 Display part 170 Input part 180 Calculation part 181 Gravity acceleration calculation part 182 Vehicle body acceleration calculation unit 183 Attachment angle calculation unit 181a, 182a Buffer 190 Storage unit 191 Attachment angle storage unit 192 Map storage unit 20 Vehicle body

Claims (4)

A mobile unit mounting device mounted on a mobile unit,
An acceleration detection unit for detecting acceleration in three axis directions;
An angular velocity detector that detects angular velocities about the first axis and the second axis;
An output signal output from the acceleration detection unit when the moving body is in a stopped state, and an output signal output from the acceleration detection unit when the moving body is moving straight ahead by acceleration or deceleration And an angle calculation unit that calculates an angle formed by the first axis and an axis corresponding to the second axis of the movable body,
An unnecessary component included in the angular velocity around the first axis detected by the angular velocity detector based on the angular velocity around the second axis detected by the angular velocity detector and the angle calculated by the angle calculator. An unnecessary component calculation unit to calculate,
An unnecessary component removing unit that subtracts the unnecessary component calculated by the unnecessary component calculating unit from the angular velocity around the first axis detected by the angular velocity detecting unit;
A device for mounting on a moving body, characterized by comprising:   The apparatus for mounting a moving body according to claim 1, wherein the first axis is a horizontal axis (pitch axis), and the second axis is a vertical axis (yaw axis). An output signal output from the acceleration detection unit when the moving body is in a stopped state, and an output signal output from the acceleration detection unit when the moving body is moving straight ahead by acceleration or deceleration And a second angle calculation unit that calculates an angle formed between the second axis and an axis corresponding to the second axis of the movable body,
The unnecessary component calculation unit corrects the angular velocity around the second axis detected by the angular velocity detection unit based on the angle calculated by the second angle calculation unit, and calculates the correction result and the angle calculation unit. The apparatus for mounting a moving body according to claim 1, wherein an unnecessary component is calculated based on the angle.   The said mobile body mounting apparatus is a portable vehicle-mounted navigation apparatus, The mobile body mounting apparatus in any one of Claims 1-3 characterized by the above-mentioned.

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