Angle processing device and signal processing method thereof

Abstract

The invention provides an angle processing apparatus and a signal processing method thereof. The angle processing device comprises an angle sensor used for sensing to obtain an angle signal; the average angular velocity estimation unit is used for obtaining an average angular velocity based on the angle signal output by the angle sensor; the angle difference calculation unit is used for calculating the reconstruction angle difference of the current moment relative to the previous moment according to the average angular velocity; and a reconstruction angle unit that calculates a reconstruction angle at the current time on the basis of the reconstruction angle at the previous time and a reconstruction angle difference at the current time with respect to the previous time. In this way, the accumulation of noise / errors can be significantly reduced, and the reconstruction angle with low noise and high precision is obtained.

Description

[Technical Field]

[0001] This invention relates to the field of sensors, and more particularly to an angle processing device and its signal processing method. [Background Technology]

[0002] In the magnetic encoder / signal processing system of the angle processing device, the angle signal is obtained after harmonic suppression and noise suppression, but this angle signal still contains residual noise / measurement error. Therefore, a more accurate / stable angle reconstruction scheme is needed. [Summary of the Invention]

[0003] To solve the above-mentioned technical problems, or at least partially solve them, embodiments of the present invention provide an angle processing device and its signal processing method.

[0004] According to one aspect of the present invention, an embodiment of the present invention provides an angle processing apparatus, comprising: an average angular velocity estimation unit for obtaining an average angular velocity based on an input angle signal; an angle difference calculation unit for calculating the reconstructed angle difference between the current moment and the previous moment based on the average angular velocity; and a reconstructed angle unit for calculating the reconstructed angle at the current moment based on the reconstructed angle at the previous moment and the reconstructed angle difference between the current moment and the previous moment.

[0005] According to another aspect of the present invention, an embodiment of the present invention provides a signal processing method for an angle processing device, comprising: obtaining an angle signal; obtaining an average angular velocity based on the angle signal; calculating the reconstructed angle difference between the current moment and the previous moment based on the average angular velocity; and calculating the reconstructed angle at the current moment based on the reconstructed angle at the previous moment and the reconstructed angle difference between the current moment and the previous moment.

[0006] Compared with the prior art, the present invention can obtain the average angular velocity of the angle signal, and calculate the reconstructed angle difference between the current moment and the previous moment based on the average angular velocity; and calculate the reconstructed angle at the current moment based on the reconstructed angle at the previous moment and the reconstructed angle difference between the current moment and the previous moment. This can significantly reduce the accumulation of noise / error and obtain a low-noise, high-precision reconstructed angle. [Attached Image Description]

[0007] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0008] Figure 1A structural block diagram of an angle processing device provided for an embodiment of the present invention.

Detailed Implementation Methods

[0009] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0010] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0011] An embodiment of the present invention provides an angle processing device that can obtain the average angular velocity of an input angle signal and calculate the reconstructed angle difference between the current moment and the previous moment based on the average angular velocity; and calculate the reconstructed angle at the current moment based on the reconstructed angle at the previous moment and the reconstructed angle difference between the current moment and the previous moment. This can significantly reduce the accumulation of noise / error and obtain the reconstructed angle with low noise and high accuracy.

[0012] Figure 1 A structural block diagram of an angle processing device provided for an embodiment of the present invention. (See diagram below.) Figure 1 As shown, the angle processing device includes: an average angular velocity estimation unit 120, an angle difference calculation unit 130, and an angle reconstruction unit 140.

[0013] An angle sensor is used to sense angle signals, and the angle signals can be output to the angle processing device in this invention after harmonic and noise suppression.

[0014] The average angular velocity estimation unit 120 is used to obtain the average angular velocity w at the current time t based on the input angle signal. t .

[0015] In one embodiment, the average angular velocity estimation unit 120 is based on the angle signal θ at the current time t. t The angle signal θ at the previous time t-1 t-1 angular difference θ t -θ t-1 Get the instantaneous angular velocity w at the current moment ′t Then, the instantaneous angular velocity w at the current time t ′t The average angular velocity w is obtained by filtering.

[0016] Specifically, the average angular velocity estimation unit includes a delay unit 121, which uses the delay unit 121 to estimate the angle signal θ at the current time t. tThe angle signal θ from the previous moment is obtained after a delay of one period. t-1 The angle signal θ at the current time t is obtained using a subtractor. t The angle signal θ at the previous time t-1 t-1 angular difference θ t -θ t-1 , i.e. w ′t =θ t -θ t-1 The average angular velocity estimation unit 120 includes a filter 123, which is a low-pass filter or an average filter. The low-pass filter or average filter is used to estimate the instantaneous angular velocity w at the current moment. ′t The average angular velocity w is obtained by filtering.

[0017] In another embodiment, the average angular velocity w can also be obtained directly from the controller.

[0018] The angle difference calculation unit 130 is used to calculate the reconstructed angle difference between the current time t and the previous time t-1 based on the average angular velocity w. Specifically, the difference in reconstruction angle between the current moment and the previous moment is: Where w is the average angular velocity and Δt is the time difference between the previous moment and the current moment.

[0019] The reconstruction angle unit 140 is based on the reconstruction angle of the previous moment. The difference in reconstruction angle between the current moment and the previous moment Calculate the reconstruction angle at the current moment. Specifically, the reconstruction angle at the current moment. for: The reconstruction angle of the previous moment is Initialization based on the angle signal obtained from the angle sensor 110

[0020] The reconstructed angle unit 140 includes a cache unit 141, which is used to cache the reconstructed angle from the previous moment.

[0021] The reconstructed angle unit further includes a 360° conversion unit 142, which is used to take the remainder of the current reconstructed angle divided by 360, i.e., θ. rebuild t =mod(θ) rebuild t The angle is normalized to the range of 0-360 degrees to prevent angle overflow.

[0022] Before the average angular velocity estimation unit 120 obtains a stable average angular velocity w, the reconstructed angle at the current moment is equal to the angle signal output by the angle sensor 110. Only after the average angular velocity estimation unit 120 obtains a stable average angular velocity w is the reconstructed angle calculated. And further calculations yielded

[0023] Preferably, the average angular velocity estimation unit 120 determines whether the average angular velocity w is stable. If the average angular velocity w is stable, the angle difference calculation unit 130 and the angle reconstruction unit 140 are activated to reconstruct the current angle based on the average angular velocity, during which time the average angular velocity remains unchanged. If the average angular velocity w is unstable, the angle difference calculation unit 130 and the angle reconstruction unit 140 are deactivated, and the input angle signal θ is... t From the perspective of reconstruction at the present moment Direct output. That is, in uniform velocity mode, i.e., when the average angular velocity is stable, the reconstructed angle is obtained by integrating the average angular velocity. This reduces the accumulation of noise / error, resulting in a low-noise, high-precision reconstructed angle. In non-uniform velocity modes, i.e., when the average angular velocity is unstable, the reconstructed angle is obtained by integrating the angular velocity. This will still introduce noise / error accumulation, so the input angle signal can be directly used as the reconstructed angle. This is equivalent to skipping the processing of the angle difference calculation unit 130 and the reconstructed angle unit 140.

[0024] In one embodiment, the stability of the average angular velocity can be determined based on the range of its variation. If the variation is within a predetermined range, the average angular velocity is considered stable; if the variation exceeds the predetermined range, the average angular velocity is considered unstable. During the period when the average angular velocity is stable, the reconstructed angle at the current moment is reconstructed based on a fixed average angular velocity.

[0025] The key, challenging, or distinctive feature of this invention lies in the following: after suppressing harmonics and noise using existing methods, the angular velocity signal is estimated / corrected to obtain a more accurate average angular velocity; then, this estimated average angular velocity is integrated / accumulated / corrected to obtain the reconstructed angle. This significantly reduces the accumulation of noise / error, resulting in a low-noise, high-precision reconstructed angle.

[0026] The present invention also provides a signal processing method for an angle processing device. The signal processing method includes:

[0027] Obtain the angle signal;

[0028] The average angular velocity is obtained based on the angle signal;

[0029] The difference in reconstructed angle between the current moment and the previous moment is calculated based on the average angular velocity;

[0030] The reconstruction angle at the current moment is calculated based on the reconstruction angle at the previous moment and the difference between the reconstruction angle at the current moment and the reconstruction angle at the previous moment.

[0031] In one embodiment, the signal processing method further includes:

[0032] Take the remainder of the current reconstruction angle when divided by 360 to normalize the current reconstruction angle to the range of 0 degrees to 360 degrees.

[0033] Specifically, the difference in reconstruction angle between the current moment and the previous moment is:

[0034] Where w is the average angular velocity, and Δt is the time difference between the previous moment and the current moment.

[0035] Reconstruction perspective at the present moment for:

[0036] The reconstruction angle of the previous moment is Initialization based on the angle signal

[0037] In one embodiment, obtaining the average angular velocity based on the angle signal includes:

[0038] The instantaneous angular velocity w at the current moment is obtained based on the angle difference between the angle signal at the current moment and the angle signal at the previous moment. ′t Then, the instantaneous angular velocity w at the current moment ′t The average angular velocity w is obtained by filtering.

[0039] In one embodiment, the signal processing method further includes:

[0040] Determine if the average angular velocity is stable. If the average angular velocity is stable, reconstruct the current angle based on the average angular velocity.

[0041] If the average angular velocity is unstable, the input angle signal will be directly output as the reconstructed angle at the current moment.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0043] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications and variations to the above embodiments within the scope of the present invention.

Claims

1. An angle processing device, characterized in that, It includes: The average angular velocity estimation unit is used to obtain the average angular velocity based on the input angle signal. Angle difference calculation unit, used to calculate the reconstructed angle difference between the current moment and the previous moment based on the average angular velocity; The reconstruction angle unit calculates the reconstruction angle at the current moment based on the reconstruction angle at the previous moment and the difference between the reconstruction angle at the current moment and the reconstruction angle at the previous moment.

2. The angle processing device according to claim 1, characterized in that, The reconstruction angle unit also takes the current reconstruction angle modulo 360 to normalize the current reconstruction angle to the range of 0 degrees to 360 degrees.

3. The angle processing device according to claim 1, characterized in that, The difference in reconstruction angle between the current moment and the previous moment is: Where w is the average angular velocity, and Δt is the time difference between the previous moment and the current moment. Reconstruction perspective at the present moment for: The reconstruction angle of the previous moment is Initialization based on the input angle signal 4. The angle processing device according to claim 1, characterized in that, The average angular velocity estimation unit obtains the instantaneous angular velocity w at the current moment based on the angle difference between the angle signal at the current moment and the angle signal at the previous moment. ′t Then, the instantaneous angular velocity w at the current moment ′t The average angular velocity w is obtained by filtering.

5. The angle processing device according to claim 4, characterized in that, The average angular velocity estimation unit includes a low-pass filter or an average filter, which is used to estimate the instantaneous angular velocity w at the current moment. ′t The average angular velocity w is obtained by filtering.

6. The angle processing device according to claim 1, characterized in that, The average angular velocity estimation unit determines whether the average angular velocity is stable. If the average angular velocity is stable, the angle difference calculation unit and the angle reconstruction unit are activated to reconstruct the current angle based on the average angular velocity. If the average angular velocity is unstable, the angle difference calculation unit and the reconstructed angle unit will be disabled, and the input angle signal will be directly output as the reconstructed angle at the current moment.

7. A signal processing method for an angle processing device, characterized in that: It includes: Obtain the angle signal; The average angular velocity is obtained based on the angle signal; The difference in reconstructed angle between the current moment and the previous moment is calculated based on the average angular velocity; The reconstruction angle at the current moment is calculated based on the reconstruction angle at the previous moment and the difference between the reconstruction angle at the current moment and the reconstruction angle at the previous moment.

8. The signal processing method according to claim 7, characterized in that, It also includes: Take the remainder of the current reconstruction angle when divided by 360 to normalize the current reconstruction angle to the range of 0 degrees to 360 degrees.

9. The signal processing method according to claim 7, characterized in that, The difference in reconstruction angle between the current moment and the previous moment is: Where w is the average angular velocity, and Δt is the time difference between the previous moment and the current moment. Reconstruction perspective at the present moment for: The reconstruction angle of the previous moment is Initialization based on the angle signal 10. The signal processing method according to claim 7, characterized in that, The process of obtaining the average angular velocity based on the angle signal includes: The instantaneous angular velocity w at the current moment is obtained based on the angle difference between the angle signal at the current moment and the angle signal at the previous moment. ′t Then, the instantaneous angular velocity w at the current moment ′t The average angular velocity w is obtained by filtering.

11. The signal processing method according to claim 7, characterized in that, It also includes: Determine if the average angular velocity is stable. If the average angular velocity is stable, reconstruct the current angle based on the average angular velocity. If the average angular velocity is unstable, the input angle signal will be directly output as the reconstructed angle at the current moment.

Images