CN115882824A - Processing method for avoiding motion reversal situation after track smoothing by using FIR filter in numerical control system - Google Patents

Abstract

The invention relates to a processing method for avoiding motion reversal after track smoothing by using an FIR filter in a numerical control system, which is characterized by comprising the following steps: the first FIR filter determines the concrete mode of the subsequent filtering processing by judging whether the first FIR filter contains a negative coefficient or not; and the second FIR filter is a filter without negative coefficients, and the first FIR filter and the second FIR filter complete alternate filtering before motion stop by performing secondary interpolation processing to prevent motion reversal. The processing method for avoiding the situation of motion reversal after smooth track by using the FIR filter in the numerical control system can effectively solve the problem of motion reversal after FIR filtering by using the variable coefficient filter, and has more outstanding practicability.

Description

In the numerical control system, the FIR filter is used to avoid motion feedback after the trajectory is smoothed. approach to the situation

technical field

The invention relates to the technical field of numerical control systems, in particular to the technical field of trajectory smoothing in numerical control systems, and specifically refers to a processing method for avoiding motion reversal after trajectory smoothing by using an FIR filter in a numerical control system.

Background technique

Among the current existing technologies, in order to make the speed and trajectory smoother, most numerical control systems usually perform filtering after interpolation. The FIR filter can control the track error before and after filtering to a certain extent, so it is often used. However, the coefficients of the constructed FIR filter sometimes appear negative, which causes the filtered trajectory to appear reverse motion, especially where the motion starts and ends. This not only affects the processing effect in these places, but also may trigger the soft limit, resulting in abnormal termination of processing. Based on this, in view of the defects existing in the prior art, there is an urgent need for a solution that can effectively prevent motion reversal when negative coefficients appear in the constructed FIR filter.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned shortcoming of prior art, provide a kind of processing method that utilizes FIR filter in the numerical control system that can effectively solve the movement reversal to avoid the situation of movement reversal after trajectory smoothing.

In order to achieve the above object, in the numerical control system of the present invention, the processing method of utilizing the FIR filter to avoid the occurrence of the motion reverse situation after the track smoothing is as follows:

Utilize the FIR filter in this numerical control system to realize the processing method that avoids the motion reversal situation after smoothing of track, its main feature is that described method comprises, is provided with:

The first FIR filter determines the specific manner of subsequent filtering processing by judging whether the first FIR filter contains negative coefficients; and

The second FIR filter, the second FIR filter is a filter without negative coefficients, the first FIR filter and the second FIR filter are processed by secondary interpolation to achieve Alternate filtering is done to prevent motion reversal.

Preferably, the first FIR filter is constructed using the amplitude-frequency characteristic of the filter obtained through calculating the curve error and the vibration suppression coefficient.

Preferably, the first FIR filter specifically performs the following processing:

Judge whether meaning negative coefficient in the first FIR filter, if not, then directly use the coefficient that currently contains in this first FIR filter to carry out filter processing; Otherwise, reconstruct according to current existing coefficient and do not contain negative coefficient The second FIR filter performs filtering processing.

Preferably, the second FIR filter specifically performs the following processing:

Perform secondary interpolation processing on the first FIR filter and the second FIR filter to construct a series of gradient filters;

When the system starts to move, first use the second FIR filter for filtering processing, and then gradually transition to using the first FIR filter for filtering processing after a preset time processing;

When the movement is about to end, first use the first FIR filter for filtering processing, and after a preset time, gradually transition to use the second FIR filter for filtering processing until the movement stops.

In the numerical control system of the present invention, the FIR filter is used to realize the processing method of avoiding the occurrence of the motion reverse situation after the trajectory is smooth, and a series of gradual filters are obtained by constructing, so that the filtering process can be performed after the secondary interpolation, When the constructed FIR filter has negative coefficients, it can effectively prevent the situation of motion reversal. Compared with the prior art, it has more prominent practicability and convenience.

Description of drawings

FIG. 1 is a schematic diagram of the result of FIR filtering in the prior art of the present invention.

Fig. 2 is a schematic diagram of the results after FIR filtering according to the present invention.

FIG. 3 is a flowchart of a processing method for avoiding motion reversal after trajectory smoothing by using an FIR filter in the numerical control system of the present invention.

Fig. 4 is a schematic diagram of the present invention to solve the problem of no motion reversal after trajectory smoothing.

Detailed ways

In order to describe the technical content of the present invention more clearly, further description will be given below in conjunction with specific embodiments.

Before describing in detail embodiments according to the present invention, it should be noted that, hereinafter, the terms "comprises", "comprises" or any other variant thereof are intended to cover a non-exclusive inclusion, thereby enabling the process of including a series of elements A method, article, or device includes not only these elements, but also other elements not expressly listed, or inherent to such a process, method, article, or apparatus.

Please refer to shown in Fig. 3, utilize the FIR filter in this numerical control system to realize the processing method that avoids the motion reversal situation after trajectory smoothing, wherein, described method comprises, is provided with:

The first FIR filter determines the specific manner of subsequent filtering processing by judging whether the first FIR filter contains negative coefficients; and

The second FIR filter, the second FIR filter is a filter without negative coefficients, the first FIR filter and the second FIR filter are processed by secondary interpolation to achieve Alternate filtering is done to prevent motion reversal.

As a preferred embodiment of the present invention, the first FIR filter is constructed using the amplitude-frequency characteristic of the filter obtained by calculating the curve error and the vibration suppression coefficient.

As a preferred embodiment of the present invention, the first FIR filter specifically performs the following processing:

Judging whether the meaning negative coefficient in the first FIR filter, if not, then directly use the coefficients contained in the first FIR filter currently to carry out filtering process; otherwise, reconstruct according to the current existing coefficients without negative coefficients The second FIR filter performs filtering processing.

As a preferred embodiment of the present invention, the second FIR filter specifically performs the following processing:

Perform secondary interpolation processing on the first FIR filter and the second FIR filter to construct a series of gradient filters;

When the system starts to move, first use the second FIR filter for filtering processing, and then gradually transition to using the first FIR filter for filtering processing after a preset time processing;

When the movement is about to end, first use the first FIR filter for filtering processing, and after a preset time, gradually transition to use the second FIR filter for filtering processing until the movement stops.

In practical application, this technical solution is realized through the following steps:

1. Construct the first FIR filter using parameters such as trajectory tolerance.

2. Determine whether the coefficients in the filter have negative numbers: if not, directly use this group of coefficients for filtering; otherwise, perform the following steps:

3. Reconstruct a set of second FIR filters without negative coefficients using the existing coefficients. The two sets of filters are used for secondary interpolation to obtain N-2 sets of different filters, where N is the order of the filter and a series of gradual filters.

4. At the beginning of the motion, use the second FIR filter for filtering, and then gradually transition to use the first FIR filter for filtering. When the movement is near the end, then the first FIR filter is used for filtering, and then gradually transition to the second FIR filter until the movement stops.

In a specific embodiment of the present invention, according to the flow chart in Figure 3, the filter coefficient 1 containing negative coefficients is first obtained, and then the filter coefficient N without negative coefficients is obtained, and the filter coefficient 2 of gradual change is obtained by using quadratic interpolation. 3, ..., N-1. As shown in Figure 4, the track before smoothing, for the start position of the track, first use the coefficient N to filter, and then use the coefficients N-1, N-2, ..., 2, 1. Then use the filter normally Filter with a factor of 1. It can effectively prevent the reversal at the beginning of the movement.

In a specific embodiment of the present invention, as shown in FIG. 4 , for the end position of the track, filter with coefficient 1 at the beginning, and then use coefficients 2, 3, ..., N until the end point is reached. It can effectively prevent the reverse at the end of the movement.

Any process or method descriptions described in flowcharts or otherwise herein may be understood as representing a module, segment or portion of code comprising one or more executable instructions for implementing specific logical functions or steps of the process , and the scope of preferred embodiments of the invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including substantially concurrently or in reverse order depending on the functions involved, which shall It is understood by those skilled in the art to which the embodiments of the present invention pertain.

It should be understood that various parts of the present invention can be realized by hardware, software, firmware or their combination. In the above-described embodiments, various steps or methods may be implemented by software or firmware stored in a memory and executed by a suitable instruction execution device.

Those of ordinary skill in the art can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed , including one or a combination of the steps of the method embodiment.

The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, and the like.

In the description of this specification, descriptions referring to the terms "an embodiment", "some embodiments", "example", "specific example", or "embodiment" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, schematic representations 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 any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

In the numerical control system of the present invention, the FIR filter is used to realize the processing method of avoiding the occurrence of the motion reverse situation after the trajectory is smooth, and a series of gradual filters are obtained by constructing, so that the filtering process can be performed after the secondary interpolation, When the constructed FIR filter has negative coefficients, it can effectively prevent the situation of motion reversal. Compared with the prior art, it has more prominent practicability and convenience.

In this specification, the invention has been described with reference to specific embodiments thereof. However, it is obvious that various modifications and changes can be made without departing from the spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive.

Claims (4)

1. utilize FIR filter in a kind of numerical control system to realize avoiding the processing method of motion reverse situation occurring after trajectory smoothing, it is characterized in that, described method comprises, is provided with: The first FIR filter determines the specific manner of subsequent filtering processing by judging whether the first FIR filter contains negative coefficients; and The second FIR filter, the second FIR filter is a filter without negative coefficients, the first FIR filter and the second FIR filter are processed by secondary interpolation to achieve Alternate filtering is done to prevent motion reversal. 2. utilize the FIR filter in the numerical control system according to claim 1 to realize the processing method of avoiding the motion reverse situation after trajectory smoothing, it is characterized in that, use curve error and damping coefficient to calculate the amplitude-frequency characteristic structure of filter the first FIR filter. 3. utilize the FIR filter in the numerical control system according to claim 2 to realize the processing method that avoids the motion reverse situation after trajectory smoothing, it is characterized in that, described first FIR filter specifically carries out following processing: Judging whether the meaning negative coefficient in the first FIR filter, if not, then directly use the coefficients contained in the first FIR filter currently to carry out filtering process; otherwise, reconstruct according to the current existing coefficients without negative coefficients The second FIR filter performs filtering processing. 4. utilize the FIR filter in the numerical control system according to claim 3 to realize the processing method that avoids the motion reverse situation occurring after trajectory smoothing, it is characterized in that, described second FIR filter specifically carries out following processing: Perform secondary interpolation processing on the first FIR filter and the second FIR filter to construct a series of gradient filters; When the system starts to move, first use the second FIR filter for filtering processing, and then gradually transition to using the first FIR filter for filtering processing after a preset time processing; When the movement is about to end, first use the first FIR filter for filtering processing, and after a preset time, gradually transition to use the second FIR filter for filtering processing until the movement stops.

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