KR101323785B1 - Device for measuring 3-dimensional rotation angle and method for measuring 3-dimensional rotation angle - Google Patents

Abstract

PURPOSE: An apparatus and a method for measuring the three-dimension rotation angle using are provided to conveniently measure the three-dimension rotation angle of an object by using only an acceleration sensor. CONSTITUTION: An apparatus for measuring the three-dimension rotation angle (1) includes a first acceleration sensor (100), a second acceleration sensor (200), and a rotation angle calculation unit (300). The first acceleration sensor is attached to an object and calculates a first acceleration value by measuring the acceleration of three axes based on a first coordinate axis. The second acceleration sensor is attached to the object and calculates a second acceleration value by measuring the acceleration of three axes based on a second coordinate axis different from the first coordinate axis. The rotation angle calculation unit calculates the rotation angle by using the first and second acceleration values. [Reference numerals] (100) First acceleration sensor; (200) Second acceleration sensor; (300) Rotation angle calculation unit

Description

Device for measuring 3-Dimensional rotation angle and Method for measuring 3-Dimensional rotation angle}

The present invention relates to a three-dimensional rotation angle measuring device and a three-dimensional rotation angle measuring method for tracking the motion of a moving object in space, and more particularly, to a three-dimensional rotation angle measuring apparatus and a three-dimensional rotation angle measuring method using an acceleration sensor. .

Motion tracking technologies are technologies that are used throughout the modern mechatronics industry and are essential for automated navigation devices or navigational devices included in such navigation devices. It is a core technology applied to the back. In addition, the motion tracking technology is not only applied to such an automated device or system, but also can be used to intuitively control a moving object or moving body in space through signal exchange or to simulate a motion in space through a signal exchange. The present invention may be easily applied to a virtual reality or augmented reality technology for projecting into an image.

In order to implement the motion tracking technique, motion analysis of an object including a three-dimensional rotational motion in space is essential. The interpretation of the three-dimensional rotational motion is usually achieved by measuring a three-dimensional three-dimensional rotational angle of the object. Conventional three-dimensional rotation angle measurement by using a gyro sensor (gyro sensor) that directly measures the rotational angle or the amount of change over time of the rotation angle, or using an accelerometer (accelerometer) for measuring the linear acceleration change of the gyro sensor and the object. This has been done through comprehensive and complementary methods. Korean Unexamined Patent Publication No. 10-2007-0054469 discloses an example of such a rotation angle measurement technology.

However, since the gyro sensor is not only expensive but also weak in shock, it may not be practical to implement motion tracking technology by applying it in an industrial field. The three-dimensional rotation angle measuring device or motion tracking device including the gyro sensor is expensive and is not widely used, and the rotation angle measuring technology or motion tracking technology combining the gyro sensor and the acceleration sensor is monopolized by a specific company. The trend is not widely used in the field.

In addition, the gyro sensor has a technical disadvantage that the error is accumulated, and in order to correct this had a problem that a high level of technical power must be added.

Republic of Korea Patent No. 10-2007-0054469 (2007.05.29)

The problem to be solved by the present invention is to provide a three-dimensional rotation angle measuring device and a three-dimensional rotation angle measuring method using an acceleration sensor, which is devised to solve this problem, does not include a gyro sensor.

The technical problems of the present invention are not limited to the above-mentioned problems, and other technical problems which are not mentioned can be clearly understood by those skilled in the art from the following description.

An apparatus for measuring a stereoscopic rotation angle according to the present invention includes: a first acceleration sensor attached to an object and measuring acceleration of three axes based on a first coordinate axis to calculate a first acceleration value; A second acceleration sensor attached to the object and measuring acceleration of three axes based on a second coordinate axis different from the first coordinate axis to calculate a second acceleration value; And a rotation angle calculator configured to calculate a rotation angle using the first acceleration value and the second acceleration value, wherein the rotation angle calculator includes: a transformation defining a conversion relationship between the first coordinate axis and the second coordinate axis; A matrix is called matrix [A], and a transformation matrix defining a conversion relationship between {a1}, which is the first measured value of the first acceleration value, and {a1 '}, which is the second measured value, is called matrix [B1]. When the transformation matrix defining the transformation relationship between the first measured value {a2} of the second acceleration value and the {a2 '} second measured value is referred to as the matrix [B2], [Equation 1] and [Math] The rotation angle is calculated by calculating the simultaneous equations of [Equation 2] or the simultaneous equations of [Equation 3] and [Equation 4].

[Equation 1]: {a1 '} = [B1] {a1}

[Equation 2]: [Inverse of A] {a2 '} = [B1] [Inverse of A] {a2}

[Equation 3]: {a2 '} = [B2] {a2}

[Equation 4]: [A] {a1 '} = [B2] [A] {a1}

The matrix [A], the matrix [B1] and the matrix [B2] are Euler rotation transformation matrices in which each component is represented by a sine function value and a cosine function value, and each of the matrix [B1] and the matrix [B2] The component may be represented by a sine function value and a cosine function value of the rotation angle.

The apparatus for measuring a three-dimensional rotation angle replaces a sine function value and a cosine function value, which are respective components of the matrix [B1] and the matrix [B2], with variables, respectively, to [Equation 1], [Equation 2], Equation 3 and Equation 4 may be linearized.

The first coordinate axis and the second coordinate axis may share any one axis.

The three-dimensional rotation angle measuring method according to the present invention includes the steps of calculating the first acceleration value by measuring the acceleration of the three axes with respect to the first coordinate axis; Calculating a second acceleration value by measuring acceleration of three axes based on a second coordinate axis different from the first coordinate axis; And calculating a rotation angle using the first acceleration value and the second acceleration value, wherein a transformation matrix defining a transformation relationship between the first coordinate axis and the second coordinate axis is referred to as a matrix [A]. And a transformation matrix defining a transformation relationship between the first measured value {a1} of the first acceleration value and the {a1 '} second measured value is called a matrix [B1], and the first order of the second acceleration value When the transformation matrix defining the transformation relationship between the measured value {a2} and the second measured value {a2 '} is called the matrix [B2], the system of equations [1] and [2], or The rotation angle is calculated by calculating the simultaneous equations of [Equation 3] and [Equation 4].

[Equation 1]: {a1 '} = [B1] {a1}

[Equation 2]: [Inverse of A] {a2 '} = [B1] [Inverse of A] {a2}

[Equation 3]: {a2 '} = [B2] {a2}

[Equation 4]: [A] {a1 '} = [B2] [A] {a1}

The matrix [A], the matrix [B1] and the matrix [B2] are Euler rotation transformation matrices in which each component is represented by a sine function value and a cosine function value, and each of the matrix [B1] and the matrix [B2] The component may be represented by a sine function value and a cosine function value of the rotation angle.

The three-dimensional rotation angle measuring method may be performed by substituting a sine function value and a cosine function value, which are the components of the matrix [A], the matrix [B1], and the matrix [B2], respectively, into the variables [Equation 1], Equation 2, Equation 3, and Equation 4 may be linearized.

The first coordinate axis and the second coordinate axis may share any one axis.

The three-dimensional rotation angle measuring device and the three-dimensional rotation angle measuring method according to the present invention has the advantage that it is convenient to measure the three-dimensional three-dimensional rotation angle of the object using only the acceleration sensor, and does not include a gyro sensor, relatively low cost In addition, there is an effect that can implement the motion tracking technology.

In addition, only the acceleration sensor is used, which makes the system easy to configure, which also has the advantage of being widely applicable to various industrial fields.

1 is a block diagram showing the configuration of a three-dimensional rotation angle measuring apparatus according to an embodiment of the present invention.
FIG. 2 is a perspective view illustrating the stereoscopic rotation angle measuring device of FIG. 1 together with a first coordinate axis and a second coordinate axis.
FIG. 3 is a diagram illustrating a relationship between a rotation of a first coordinate axis or a second coordinate axis of FIG. 2 and a stereoscopic rotation angle.
4A and 4B are conceptual views illustrating a transformation relationship between the first coordinate axis and the second coordinate axis of FIG. 2.
5 is a flowchart illustrating a three-dimensional rotation angle measuring method according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is only defined by the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a stereoscopic rotation angle measuring device and a stereoscopic rotation angle measuring method according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 5.

First, referring to FIGS. 1 and 2, the stereoscopic rotation angle measuring apparatus 1 according to an embodiment of the present invention is a specific object having a motion in space, that is, a moving body or an object to be tracked. Rotation angle calculation unit 300 for calculating the rotation angle of the object by using the first acceleration sensor 100 and the second acceleration sensor 200 attached to the object and the different acceleration values measured from the acceleration sensor. It includes.

In this case, as illustrated in FIG. 2, the first acceleration sensor 100 and the second acceleration sensor 200 are orientated in different directions with respect to the reference coordinate axis where the acceleration value is measured. The instantaneous acceleration value and the changed value indicated by the same rotation of are calculated based on different criteria. The rotation angle calculation unit 300 can easily measure the rotation angle of the body by calculating a formula representing the relationship between changes in physical quantities at the time of rotation using the data of the acceleration values calculated in this way. Data for deciding the rotation angle deterministically by the rotation angle calculator 300 is provided from both the first acceleration sensor 100 and the second acceleration sensor 200.

Therefore, in addition to the first acceleration sensor 100 and the second acceleration sensor 200, for example, a separate measuring device such as a gyro sensor (Gyro sensor) that directly detects data on the rotation angle of the body is not required. It is possible to implement an effective three-dimensional rotation angle measuring device 1 by a simple configuration including the first acceleration sensor 100, the second acceleration sensor 200 and the rotation angle calculation unit 300. As a result, the operation tracking technology can be used at low cost even in the industrial field, and the operation tracking technology can be applied to a wide range of fields due to the simple configuration. Hereinafter, each component of the three-dimensional rotation angle measuring device 1 having such a feature and its operation will be described in more detail.

First, the first acceleration sensor 100 and the second acceleration sensor 200 acquires a change in material quality as an electrical signal and measures an instantaneous acceleration value due to the movement of the object Ob, for example, a piezoelectric element ( Piezoelectric material) or Mems (Micro electro mechanical system) may be included. The first acceleration sensor 100 and the second acceleration sensor 200 are attached to different positions of the object Ob and measure acceleration values based on different coordinate axes, respectively.

In this case, the acceleration measured by the first acceleration sensor 100 and the second acceleration sensor 200 is a reference coordinate axis, that is, a first coordinate axis that is an acceleration value measurement reference of the first acceleration sensor 100 (see FIG. 2). Linear acceleration value measured from a second coordinate axis (see X2, Y2, Z2 pair of FIG. 2), which is the reference value of the acceleration value of the second acceleration sensor 200, and the X1, Y1, Z1 pair reference. However, this is not an angular acceleration value that directly represents rotational motion. The first acceleration sensor 100 and the second acceleration sensor 200 measure acceleration components of three axes based on the first coordinate axis and the second coordinate axis, respectively, and calculate acceleration values in a vector format for each reference coordinate axis. It can consist of a three-axis acceleration sensor.

In detail, the first acceleration sensor 100 and the second acceleration sensor 200 may be attached to both surfaces of the object Ob in a symmetrical form, as shown in FIG. Any one of the axes, preferably the Z1 axis of the first coordinate axis and the Z2 axis of the second coordinate axis, may lie on the same line and be shared with each other. At this time, the axis Z1 and the axis Z2 face in opposite directions to each other.

Through this arrangement, the first coordinate axis and the second coordinate axis may not be oriented in the same direction while minimizing the positional difference between the first acceleration sensor 100 and the second acceleration sensor 200 attached to the object Ob. It is. In addition, since the first coordinate axis and the second coordinate axis share one axis with each other, an expression representing a conversion relationship between the first coordinate axis and the second coordinate axis may be displayed in a simpler form.

At this time, the first coordinate axis and the second coordinate axis are not mirror-symmetrical as shown, and through proper rotation, X1 and X2, Y1 and Y2, and Z1 and Z2 are in a rotationally symmetrical relationship that can be completely overlapped, respectively.

The object Ob may be the object itself for tracking the motion, or may be combined with the object and move with the object. In other words, the first acceleration sensor 100 and the second acceleration sensor 200 may be directly attached to the object to be tracked, but are not limited thereto, and are attached to the object Ob formed separately from the tracked object. After that, it may be fixed to the object together with the object Ob. Through this, the acceleration change due to the movement of the object and the object Ob may be closely measured.

The object Ob may be, for example, a printed circuit board (PCB) substrate on which a specific type of circuit is printed, and together with the first acceleration sensor 100 and the second acceleration sensor 200 using various fixing methods. It may be fixed to the subject to be tracked. The first acceleration sensor 100 and the second acceleration sensor 200 are coupled to such a substrate and electrically connected to each other, thereby exchanging signals with each other or calculating acceleration values calculated according to rotation of the object and the object Ob. It can be easily delivered to 300.

The rotation angle calculator 300 calculates the rotation angle by using the first acceleration value calculated from the first acceleration sensor 100 and the second acceleration value calculated from the second acceleration sensor 200. The rotation angle calculator 300 may be formed of, for example, one or a plurality of microprocessors connected in parallel. The rotation angle calculator 300 may be attached to one side of the PCB substrate, for example, the first acceleration sensor 100 and the second acceleration sensor ( One circuit including 200 may be configured.

Therefore, the first acceleration value and the second acceleration value calculated from the first acceleration sensor 100 and the second acceleration sensor 200 are easily transmitted to the rotation angle calculator 300. However, the connection method between the rotation angle calculator 300, the first acceleration sensor 100, and the second acceleration sensor 200 does not need to be limited to the method using the PCB. The first and second acceleration sensors 100 and 200 and the rotation angle calculator 300 may be easily connected to each other by using various connection methods capable of transmitting signals by wire or wirelessly.

In particular, when the first and second acceleration sensors 100 and 200 and the rotation angle calculator 300 are connected by using a remote communication method, the rotation angle calculator 300 is attached to or fixed to the object Ob. There is no need to move, it is installed with the output equipment disposed around the object (Ob) and can receive data of the acceleration value remotely. Therefore, by lightening the object Ob, it is possible not only to induce the movement of the object Ob normally, but also by connecting the rotation angle calculator 300 to an external system having a large computing capacity, thereby making the rotation angle calculation and output process more quickly. You can also lose.

The rotation angle calculator 300 receives the first acceleration value and the second acceleration value to calculate a stereoscopic rotation angle of the object Ob. Since the object Ob changes in motion due to rotation, the first acceleration value changes into primary and secondary measurement values with a parallax, and the second acceleration value also has a primary parallax and a second parallax with the same parallax. Change to the difference measurement. The rotation angle calculator 300 conveniently calculates the rotation angle of the object Ob by calculating a reverse relationship between the first and second measured values of each of the first and second acceleration values.

In order to calculate the rotation angle, the rotation angle calculation unit 300 includes a transformation matrix [B1] defining a conversion relationship between the first measurement value {a1} and the second measurement value {a1 '} of the first acceleration value, A transformation matrix [B2] defining a transformation relationship between the first measured value {a2} and the second measured value {a2 '} of the second acceleration value, and between the first coordinate axis and the second coordinate axis, which are reference coordinate axes of the acceleration value. Contains information about the transformation matrices [A] and [inverse of A] that define the transformation relationship. Through this, at least four equations can be derived as follows.

[Equation 1]: {a1 '} = [B1] {a1}

[Equation 2]: [Inverse of A] {a2 '} = [B1] [Inverse of A] {a2}

[Equation 3]: {a2 '} = [B2] {a2}

[Equation 4]: [A] {a1 '} = [B2] [A] {a1}

In this case, the matrix [A], the matrix [B1], and the matrix [B2] are all Euler rotation matrices in which each component is represented by a sine function value and a cosine function value, and in particular, the matrix [B1] And the matrix [B2] is expressed by its sine and cosine function values of the rotation angle defining the rotation of the object Ob. The rotation angle is an unknown value whose value is not specified before the calculation, but the matrix [A] is given both of its component values depending on the attachment state or arrangement state of the first acceleration sensor 100 and the second acceleration sensor 200. The value is pre-populated before the operation.

In the above equations, [Equation 1] and [Equation 2], the conversion relationship between the first and second measured value of the first acceleration value and the first and second measured value of the second acceleration value Equation 3 and Equation 4 represent the transformation relationship between the first and second measured values of the first acceleration value and the first order of the second acceleration value. And all the transformation relationships between the secondary measurement values based on the second coordinate axis. Accordingly, simultaneous equations in which [Equation 1] and [Equation 2] are linked to each other or [Equation 3] and [Equation 4] are linked to each other can be obtained based on different coordinate axes. By calculating any one of the simultaneous equations, the components of the transformation matrix [B1] or the transformation matrix [B2] can be obtained and the corresponding set of rotation angles can be calculated.

At this time, the set of rotation angles obtained from the transformation matrix [B1] and the set of rotation angles obtained from the transformation matrix [B2] are based on different coordinate axes, and thus have different values. However, this indicates that the rotational motion of the object Ob is equally represented because only one rotational motion is expressed with respect to different coordinate axes, and therefore, the attitude, movement, and rotation of the object Obb can be obtained by taking only one of them. There is no problem in tracking status etc. That is, the rotation angle calculation unit 300 is a system obtained by combining [Equation 1] and [Equation 2] and the system obtained by combining [Equation 3] and [Equation 4] in order to calculate the rotation angle. It is sufficient to compute only one of the equations, and it is not necessary to compute all of the system equations that can be obtained. This allows the rotation angle to be calculated simply.

Hereinafter, the operation of the rotation angle and the rotation angle will be described in more detail.

3 is a diagram illustrating a relationship between a rotation of a first coordinate axis or a second coordinate axis of FIG. 2 and a stereoscopic rotation angle, and FIGS. 4A and 4B are conceptual views illustrating a transformation relationship between the first coordinate axis and the second coordinate axis of FIG. 2. to be.

Referring to FIG. 3, the set of rotation angles θ1, θ2, and θ3 obtained through such a calculation process defines a rotational motion in space, and may have at least three components according to the relationship between coordinate axes.

The rotation in space can be represented by the rotational transformation of the reference coordinate axis and its inverse transformation, which is known as Euler rotational transform. Briefly described, first, the reference coordinate axis is oriented in the X, Y, and Z axis directions in the drawing before the start of rotation. In this state, the rotation angle of θ1 can be defined primarily with the Z axis as the rotation center. The angle of rotation θ1 lies on a plane perpendicular to the Z axis (see P1 in the drawing).

After the rotation by [theta] 1 is made, the X-axis overlaps with the straight line (see N on the drawing). In this state, the rotation angle by θ2 can be defined again using the straight line N as the rotation center. The rotation angle θ2 causes the axis Z and the plane P1 to move to the axis Z 'and the plane P2, respectively. Although not shown separately in the figure, the rotation angle θ2 lies on a plane perpendicular to the plane P1.

In the state of being rotated by θ1 and θ2 in turn, the rotation angle θ3 can be defined by using the converted Z 'axis as the center of rotation. The rotation angle θ3 lies on the transformed plane P2 perpendicular to the Z 'axis.

In this way, a rotation angle set having three components defined in different directions in space can be defined, thereby fully representing the rotational motion.

When the first acceleration sensor (see 100 in FIG. 2) and the second acceleration sensor (see 200 in FIG. 2) are attached to the object (see Ob in FIG. 2) and rotate together with the object Ob, the first acceleration sensor ( The conversion relationship in which the first acceleration value measured from 100 is changed into the first and second measured values, and the second acceleration value measured from the second acceleration sensor 200 are also changed into the first and second measured values. The transformation relationship may be expressed as an inverse transformation relationship of the coordinate axis transformation, that is, a relationship in which each acceleration value vector changes inversely along a set of rotation angles while the first coordinate axis or the second coordinate axis is fixed. The data of the rotation angle set is represented by the sine function value and the cosine function value included in the components of the rotation transformation matrix [B1] and the matrix [B2] as described above.

[Equation 5]:

[Equation 5] specifically illustrates a matrix [B1] representing the rotation transformation of the first coordinate axis. In the case of the matrix [B2], the rotation angle can be expressed in a matrix of exactly the same type except that the rotation angle is different.

Meanwhile, the first measured value {a1} and the second measured value {a1 '} of the first acceleration value are triaxial components a1x, a1y, a1z and a1x', a1y ', and a1z', respectively, as shown in [Equation 6]. It can be expressed as a column vector with).

Equation 6:

 Since the values of the first measured value {a1} and the second measured value {a1 '} of the first acceleration value are numerically given, Equation 1 described above: {a1'} = [B1] {a1} is a rotation angle. It is reduced to three simultaneous equations containing θ1, θ2, and θ3 as variables. Therefore, it can be calculated to obtain a set of rotation angles composed of θ1, θ2, and θ3.

However, due to the components of the transformation matrix [B1] which are complicatedly expressed as the sine function value and the cosine function value in the actual operation process, the operation speed may decrease or the operation process may be stopped. In order to solve this problem, the sine function and the cosine function of the rotation angles θ1, θ2, and θ3 shown in the transformation matrix [B1] are replaced with a single variable so that [Equation 1] is expressed as [Equation 7]. It can be 'linearized' so that no sine or cosine function value is directly included in the equation.

Equation 7:

In this case, c1 to c3 and s1 to s3 are independent variables, and c1 = cosθ1, c2 = cosθ2, c3 = cosθ3, s1 = sinθ1, s2 = sinθ2, and s3 = sinθ3. However, since the number of simultaneous equations obtained from Equation 7 is three, the values of the variables c1 to c3 and the variables s1 to s3 cannot be obtained therefrom. Therefore, using the transformation relations of FIGS. 4A and 4B, one more [Equation 8], which is a matrix product of the transformation matrix B1, is obtained.

Equation 8:

4A and 4B, as described above, the first coordinate axis and the second coordinate axis may also be defined as Euler rotation transformation equations. The transformation matrix [A] is a matrix defining the relationship between these different coordinate axes, and thus the first and second measurement values of the acceleration values measured with respect to each coordinate axis are shown in FIGS. 4A and 4B. The matrix [A] and the matrix [inverse of A] can be converted into measurements based on different coordinate axes.

Specifically, the first measured value {a1} of the first acceleration value measured based on the first coordinate axis is measured value [A] {a1} based on the second coordinate axis corresponding thereto through the transformation matrix [A]. The second measured value {a1 '} of the first acceleration value measured on the basis of the first coordinate axis is converted to the measured value [A] {a1' on the corresponding second coordinate axis through the transformation matrix [A]. Is converted to}. Since the converted measured values [A] {a1} and [A] {a1 '} represent the same rotation with respect to the first coordinate axis, Equation 4 described above: [A] {a1'} = [B2] [A] {a1} is derived.

Further, the first measured value {a2} of the second acceleration value measured based on the second coordinate axis is measured based on the first coordinate axis corresponding thereto through the transformation matrix [inverse matrix of A] [inverse matrix of A] { the second measured value {a2 '} of the second acceleration value measured based on the second coordinate axis is converted to the measured value based on the second coordinate axis corresponding thereto through the transformation matrix [inverse matrix A]. Inverse of A] {a2 '}. Since the measured measurements [inverse matrix of A] {a2} and [inverse matrix of A] {a2 '} also represent the same rotation with respect to the second coordinate axis, Equation 2 described above: [inverse matrix of A] {a2 '} = [B1] [inverse matrix of A] {a2} is derived.

[Equation 8] is a concrete expression of [Equation 2], three more equations can be obtained from it. Accordingly, six simultaneous equations obtained from Equations 7 and 8 can be calculated to obtain the values of six variables c1 to c3 and s1 to s3. In this way, the rotation angle can be easily calculated.

Meanwhile, the calculated rotation angle may be output after being converted into another type of three-dimensional rotation angle represented by, for example, a set of roll angle, pitch angle, and yaw angle by using a specific conversion equation. At this time, since the three-dimensional rotation angle set θ1, θ2, and θ3 and the set of roll angle, pitch angle, yaw angle on the present specification may include extra rotation components that do not coincide with each other, the conversion equation for converting the same is It can be obtained by combining the equations of the transformation matrix to compensate for the extra rotational components. Specifically, this is derived in a simple form as shown in Equation 9 below.

Equation 9:

Accordingly, by applying the calculated stereoscopic rotation angle sets θ1, θ2, and θ3 to this, it is possible to obtain a solid angle conversion equation as shown in Equation 10 below.

Equation 10:

At this time, θR, θP, and θY represent roll angle, pitch angle, and yaw angle, respectively. The set of rotation angles calculated through this conversion equation can be easily converted and outputted, and the data of the converted rotation angle set can be provided to other control devices using the three-dimensional rotation angle format of the roll angle, pitch angle, and yaw angle. Can be effectively used.

In addition, the calculation process of the rotation angle described so far has described a method of calculating the rotation angle expressed in the transformation matrix [B1] by combining [Equation 1] and [Equation 2] and using the transformation relationship of FIG. This logic can be applied equally to calculating the rotation angle expressed in the transformation matrix [B2] by using the transformation relationship shown in FIG. 4A. .

Hereinafter, the stereoscopic rotation angle measuring method according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 5.

5 is a flowchart illustrating a three-dimensional rotation angle measuring method according to an embodiment of the present invention.

As shown in FIG. 5, the method for measuring the stereoscopic rotation angle of an object includes calculating a first acceleration value (S100), calculating a second acceleration value (S200), and calculating the calculated acceleration value on a first coordinate axis. Or (S300) converting a value based on the second coordinate axis (S300), calculating equations representing the relationship between the converted acceleration values (S400), and outputting the calculation result (S500). In addition, after the output step (S500) may further include a step (S600) of re-entering the acceleration in accordance with the change of the motion state of the object, so that the procedure for measuring the rotation angle as the new acceleration is input can be repeated again. . Each step will be described in more detail below.

The calculating of the first acceleration value (S100) and the calculating of the second acceleration value (S200) include the steps of sequentially measuring each of the first measurement value and the second measurement value according to the rotation of the object. Each step proceeds simultaneously for the same rotation. As a result, it is possible to closely grasp the movement of the object with respect to different coordinate axes and obtain at least two simultaneous equations expressed in matrix relation for the same rotation.

The calculated acceleration value is transmitted to the rotation angle calculator 300 through a wired or wireless signal transmission method. The rotation angle calculator 300 converts all of the transmitted acceleration values into measured values based on only one of the first coordinate axis and the second coordinate axis by using the above-described conversion relationship between the coordinate axes (S300). Accordingly, the system of equations [Equation 1] and [Equation 2] described above or the system of equations [Equation 3] and [Equation 4] can be easily calculated, the rotation angle calculation unit 300 is a calculation process To calculate the set of rotation angle by performing (S400).

The calculated rotation angle is output and transmitted to other equipment. In this case, the other equipment may be an output terminal such as a monitor or LCD panel which visually displays the rotation angle directly, and is not an indicator such as an automated navigation device or a navigation device included in the navigation device. Or the like. In addition, when the three-dimensional rotation angle measuring device is applied to the robot, the robot can maintain a stable posture in connection with the motion control system (robot). In addition, the three-dimensional rotation angle measuring device according to the present invention can be applied to various kinds of devices in which motion tracking technology is implemented.

On the other hand, if the movement or posture of the object changes after the acceleration value is output, a new acceleration is input to the acceleration sensor (S600), which may be calculated as an acceleration value having three axis components again. Therefore, a new rotation angle can be calculated again, and by repeating this process, the movement of the object can be continuously recognized and responded to. This makes motion tracking technology more effective.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken in conjunction with the present invention. You will understand. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

1: stereoscopic rotation angle measuring device 100: the first acceleration sensor
200: second acceleration sensor 300: rotation angle calculation unit
Ob: object θ1, θ2, θ3: rotation angle
N: straight line P1, P2: plane

Claims (8)

A first acceleration sensor attached to the object and measuring acceleration of three axes based on the first coordinate axis to calculate a first acceleration value;
A second acceleration sensor attached to the object and measuring acceleration of three axes based on a second coordinate axis different from the first coordinate axis to calculate a second acceleration value; And
It includes a rotation angle calculation unit for calculating a rotation angle by using the first acceleration value and the second acceleration value,
The rotation angle calculation unit,
A transformation matrix defining a transformation relationship between the first coordinate axis and the second coordinate axis is called matrix [A], and the first measurement value {a1} and the second measurement value {a1 '} The transformation matrix defining the transformation relation between the two is called matrix [B1], and the transformation matrix defining the transformation relation between the first measurement value {a2} of the second acceleration value and the second measurement value {a2 '}. Is the matrix [B2],
A three-dimensional rotation angle measuring device for calculating the rotation angle by calculating the simultaneous equations of [Equation 1] and [Equation 2], or the equation of [Equation 3] and [Equation 4].
[Equation 1]: {a1 '} = [B1] {a1}
[Equation 2]: [Inverse of A] {a2 '} = [B1] [Inverse of A] {a2}
[Equation 3]: {a2 '} = [B2] {a2}
[Equation 4]: [A] {a1 '} = [B2] [A] {a1} The method of claim 1,
The matrix [A], the matrix [B1] and the matrix [B2] are Euler rotation transformation matrices in which each component is represented by a sine function value and a cosine function value.
And each component of the matrix [B1] and the matrix [B2] is represented by a sine function value and a cosine function value of the rotation angle. 3. The method of claim 2,
[Equation 1], [Equation 2], [Equation 3], and each of the components of the matrix [B1] and the matrix [B2] by substituting a sine function value and a cosine function value with variables. Three-dimensional rotation angle measuring device to linearize the [Equation 4]. The method of claim 1,
And the first coordinate axis and the second coordinate axis share any one axis. Calculating a first acceleration value by measuring acceleration of three axes based on the first coordinate axis;
Calculating a second acceleration value by measuring acceleration of three axes based on a second coordinate axis different from the first coordinate axis; And
Calculating a rotation angle by using the first acceleration value and the second acceleration value;
A transformation matrix defining a transformation relationship between the first coordinate axis and the second coordinate axis is called matrix [A], and the first measurement value {a1} and the second measurement value {a1 '} The transformation matrix defining the transformation relation between the two is called matrix [B1], and the transformation matrix defining the transformation relation between the first measured value {a2} and the second measured value {a2 '} of the second acceleration value. Is the matrix [B2],
A three-dimensional rotation angle measuring method for calculating the rotation angle by calculating the simultaneous equations of [Equation 1] and [Equation 2], or the simultaneous equations of [Equation 3] and [Equation 4].
[Equation 1]: {a1 '} = [B1] {a1}
[Equation 2]: [Inverse of A] {a2 '} = [B1] [Inverse of A] {a2}
[Equation 3]: {a2 '} = [B2] {a2}
[Equation 4]: [A] {a1 '} = [B2] [A] {a1} 6. The method of claim 5,
The matrix [A], the matrix [B1] and the matrix [B2] are Euler rotation transformation matrices in which each component is represented by a sine function value and a cosine function value.
And each component of the matrix [B1] and the matrix [B2] is represented by a sine function value and a cosine function value of the rotation angle. The method according to claim 6,
[Scheme 1], [Scheme 2], and [Sample function value and cosine function value which are respective components of the matrix [A], the matrix [B1] and the matrix [B2] are replaced by variables. Equation 3], and the method of measuring the three-dimensional rotation angle to linearize the [Equation 4]. 6. The method of claim 5,
3. The method of claim 3, wherein the first coordinate axis and the second coordinate axis share any one axis.

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