A feed rate control method and numerical control system

Abstract

The present invention relates to a feed rate control method and a numerical control system in a numerical control system, the method comprising: the numerical control system receives a target feed rate input by a user; when it is determined that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, according to the basic parameters of the current interpolation cycle and the target feed rate in the planned interpolation information, the updated position points in the planned interpolation information are obtained according to a predefined rate update strategy, and the position points are the position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that the servo drive device of the numerical control system performs a cutting operation according to the position points. When the above method adjusts the feed rate during the processing, the numerical control system does not need to re-plan the speed, so that the real-time performance of the rate adjustment is guaranteed, and the speed changes smoothly, which is suitable for different processing scenarios.

Description

Technical Field

[0001] The present invention relates to the field of numerical control systems, and in particular to a method for controlling a feed rate in a numerical control system and a numerical control system. Background Art

[0002] Motion control is the core part of the CNC system, and real-time feed rate adjustment is one of the key technologies of motion control. In the actual production process, the change of feed speed affects the processing accuracy and quality; in order to achieve the ideal processing effect, the CNC system must provide the function of real-time feed speed adjustment. In general, the feed speed value of the processing is determined by the given feed speed and the feed rate input by the user. The real-time feed speed adjustment is achieved by real-time feed rate adjustment. The speed change stability and real-time responsiveness during the real-time feed rate adjustment are one of the indicators to measure the quality of the CNC system.

[0003] The method of adjusting the feed rate in the prior art includes: when adjusting the feed rate, re-planning the speed of the remaining processing sections according to the current speed, the current position, the maximum speed and the position of the end point, so as to achieve the purpose of speed adjustment; each time the rate is changed, the speed planning needs to be re-performed, which will increase the computing load of the CNC system and affect the real-time response of the speed adjustment of the CNC system; and the re-planned processing section may cause a sudden change in speed, affecting the processing effect. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for controlling a feed rate in a numerical control system and a numerical control system.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] In a first aspect, an embodiment of the present invention provides a method for controlling a feed rate in a numerical control system, comprising:

[0009] S10, the CNC system receives the target feed rate input by the user;

[0010] S20, when the numerical control system determines that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, the updated position points in the planned interpolation information are obtained according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, according to a predefined rate update strategy, and the position points are the position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that the servo drive device of the numerical control system performs a cutting operation according to the position points;

[0011] The predefined rate update strategy includes: using a piecewise polynomial method to obtain a feed rate curve and calculate interpolation cumulative time information, and then combining the interpolation function in the planned interpolation information to obtain the position point.

[0012] Optionally, the S20 includes:

[0013] S201, the numerical control system determines whether the numerical control system is in a non-stop state based on the state identifier of the numerical control system, and if so, executes S202;

[0014] S202, the numerical control system obtains the planned interpolation information of the current motion segment, and determines whether the target feed rate is the same as the feed rate at the current moment in the planned interpolation information. If they are the same, the target feed rate is ignored; otherwise, S203 is executed;

[0015] S203: The numerical control system obtains updated position points in the planned interpolation information according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate according to a predefined rate update strategy.

[0016] Optionally, the S203 includes:

[0017] The feed rate curve is obtained by piecewise polynomial method and the interpolation cumulative time information is calculated, and then the position point is obtained by combining the interpolation function in the planning interpolation information.

[0018] S203-1, using the piecewise polynomial of formula (1) to obtain a feed rate curve;

[0019] Formula (1)

[0020] Among them, r0 is the starting feed rate, v m is the speed when the feed rate is 1, v0 is the starting speed; j s is a given parameter, t1, t2, t3 are the adjustment time of each stage of the feed rate curve segment, τ i , i=1,2,3 are local time coordinates, indicating the adjustment time with the starting point of each stage as the time zero point, r1,r2 are the feed rate values ​​at τ1=t1,τ2=t2 respectively; t represents the cumulative adjustment time with the starting point of the initial adjustment feed rate as the time zero point; n is the positive and negative sign judgment value, when r0≥r a When n=1, r0<r a When n=2, r a is the target feed rate;

[0021] S203-2, according to the feed rate curve, the feed rate adjustment cumulative time t in the planned interpolation information, and obtaining the current interpolation time increment ΔT;

[0022] S203-3, acquiring interpolation cumulative time information T+ΔT according to the interpolation time increment ΔT;

[0023] S203 - 4 . Obtain the position point according to the interpolation cumulative time information T+ΔT and the interpolation function.

[0024] Optionally, the S203-2 includes: interpolating the time increment to be ΔT=T s *r(t), where T s To plan the interpolation period in the interpolation information;

[0025] In the present invention, the feed rate adjustment cumulative time accumulates one interpolation cycle during interpolation in each interpolation cycle; the above feed rate adjustment cumulative time is the adjustment time accumulation with the starting point of adjusting the feed rate as the time zero point.

[0026] Optionally, the S203-4 includes:

[0027] In a two-dimensional coordinate system, the position point is obtained according to formula (2);

[0028] Formula (2)

[0029] Among them, (x i ,y i ) is the interpolation position in the Cartesian coordinate system, f x are the x interpolation axis interpolation function, f y are the interpolation functions of the y interpolation axis respectively, and T is the cumulative interpolation time of the previous interpolation cycle.

[0030] Optionally, the control method further includes:

[0031] S30, the numerical control system sends the position point to the servo system, so that the servo drive device of the servo system performs a cutting operation according to the position point. The servo system is electrically connected to the numerical control system.

[0032] Optionally, the control method further includes:

[0033] S40: If the numerical control system is in a stopped state, the target feed rate is recorded, and the position point is acquired at the target feed rate after the numerical control system is started.

[0034] In a second aspect, an embodiment of the present invention further provides a numerical control system, comprising:

[0035] A target feed rate acquisition module is used to receive a target feed rate input by a user;

[0036] A status signal acquisition module is used to obtain the status of the CNC system;

[0037] a processing module, configured to, when determining that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, obtain updated position points in the planned interpolation information according to a predefined rate update strategy based on basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, wherein the position points are position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that a servo drive device of the numerical control system performs a cutting operation according to the position points;

[0038] The predefined rate update strategy includes: using a piecewise polynomial method to obtain a feed rate curve and calculate interpolation cumulative time information, and then combining the interpolation function in the planned interpolation information to obtain the position point.

[0039] Optionally, the numerical control system further comprises:

[0040] The sending module is used to send the position point to the servo system so that the servo drive device of the servo system performs a cutting operation according to the position point.

[0041] In a third aspect, an embodiment of the present invention further provides a control device, which includes the numerical control system described in the second aspect above.

[0042] In a fourth aspect, an embodiment of the present invention further provides a control device, comprising: a memory and a processor, wherein the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory and execute the steps of the feed rate control method in a numerical control system described in any one of the first aspects above.

[0043] (III) Beneficial effects

[0044] When the method of the embodiment of the present invention adjusts the feed rate during the processing, by updating or adjusting the unprocessed position points of the motion segment, the numerical control system does not need to re-plan the speed, thereby ensuring the real-time performance of the rate adjustment and smooth speed changes.

[0045] The numerical control system of the present invention can adjust the feed rate curve by adjusting given parameters, so that the feed rate control and adjustment process can be applicable to cutting processing scenarios of different plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A flow chart of a method for controlling a feed rate in a numerical control system provided by an embodiment of the present invention;

[0047] Figure 2 A feed rate control speed curve diagram in one embodiment of the present invention;

[0048] Figure 3 A feed rate control acceleration curve diagram in one embodiment of the present invention;

[0049] Figure 4 A feed rate adjustment curve diagram when the feed rate is adjusted from 100% to 200% in one embodiment of the present invention;

[0050] Figure 5 A feed rate adjustment curve diagram when the feed rate is adjusted from 200% to 0.01% in one embodiment of the present invention;

[0051] Figure 6 The feed rate adjustment curve diagram is shown when the feed rate is adjusted from 0.01% to 100% in one embodiment of the present invention;

[0052] Figure 7 A flow chart of a method for controlling a feed rate in a numerical control system provided by another embodiment of the present invention;

[0053] Figure 8 Schematic diagram of the structure of a numerical control system in one embodiment of the present invention. DETAILED DESCRIPTION

[0054] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0055] The method of this embodiment is used to determine the position coordinates of each node in a motion segment in a numerical control system. A motion segment refers to a continuous processing path segment that moves in a given motion form during the sheet metal processing process. Specifically, it can be represented as an arc or a straight line in the graphics displayed on the control device interface.

[0056] In the embodiment of the present invention, different acceleration and deceleration algorithms determine different motion forms. After determining the acceleration and deceleration algorithm and the motion segment path, the path can be speed planned. The corresponding interpolation function can be obtained through the information after speed planning. The interpolation function is a value corresponding to the interpolation cumulative time. The interpolation cumulative time of each interpolation cycle will accumulate a time increment, and then the corresponding interpolation function value is obtained through the interpolation cumulative time as the final output position coordinate.

[0057] Embodiment 1

[0058] like Figure 1 and Figure 7 As shown, an embodiment of the present invention provides a method for controlling a feed rate in a numerical control system. The execution subject of the method of this embodiment may be an electronic device / control device that carries the numerical control system. The specific method includes the following steps:

[0059] S10, the CNC system receives the target feed rate input by the user;

[0060] S20. When the CNC system determines that the feed rate at the current moment is different from the target feed rate and the CNC system is in a non-stop state, the CNC system obtains the updated position points in the planned interpolation information according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, according to a predefined rate update strategy. The position points are the position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that the servo drive device of the CNC system performs the cutting operation according to the position points, thereby ensuring the smoothness of the speed change and the rapid responsiveness when the feed rate is adjusted in real time.

[0061] The above-mentioned predefined rate update strategy includes: using a piecewise polynomial method to obtain a feed rate curve and calculate interpolation cumulative time information, and then combining the interpolation function in the planned interpolation information to obtain the position point.

[0062] For example, the above S20 may include the following sub-steps:

[0063] S201, the numerical control system determines whether the numerical control system is in a non-stop state based on the state identifier of the numerical control system, and if so, executes S202;

[0064] S202, the numerical control system obtains the planned interpolation information of the current motion segment, and determines whether the target feed rate is the same as the feed rate at the current moment in the planned interpolation information. If they are the same, the target feed rate is ignored (i.e., the interpolation time increment is calculated by the current feed rate and executed according to the existing execution method); otherwise, S203 is executed;

[0065] S203: The numerical control system obtains updated position points in the planned interpolation information according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate according to a predefined rate update strategy.

[0066] When the method of the embodiment of the present invention adjusts the feed rate during the processing, the unprocessed position points of the motion segment are updated or adjusted, so that the numerical control system does not need to re-plan the speed, so that the real-time performance of the rate adjustment is guaranteed and the speed changes smoothly. At the same time, the numerical control system can be used to adjust the rate curve by adjusting given parameters, so that the feed rate adjustment is suitable for different processing scenarios.

[0067] Embodiment 2

[0068] Combination Figures 1 to 6As shown, this embodiment describes the steps of the above embodiment in detail. The execution subject of the method of this embodiment is a numerical control system integrated in a certain electronic device, and the numerical control system has an operation interface. The user can input the feed speed, feed ratio or other feed information based on the operation interface. The numerical control system in actual operation is also connected to the servo system so that the determined position point is output to the servo system to perform subsequent processing operations.

[0069] A10, the CNC system receives the target feed rate input by the user;

[0070] A20. The numerical control system determines whether the numerical control system is in a non-stop state based on the state identifier of the numerical control system. If so, execute A30; otherwise, execute A50.

[0071] A30, the numerical control system obtains the planned interpolation information of the current motion segment, and determines whether the target feed rate is the same as the feed rate at the current moment in the planned interpolation information. If they are the same, the target feed rate is ignored; otherwise, A31 is executed;

[0072] A31. When it is determined that the feed rate at the current moment is different from the target feed rate and the CNC system is in a non-stop state, the CNC system obtains the updated position point, i.e., the position coordinates, in the planned interpolation information according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, according to a pre-defined rate update strategy.

[0073] A40. The numerical control system sends the position point to the servo system so that the servo drive device of the servo system performs a cutting operation according to the position point.

[0074] A50, if the numerical control system is in a stopped state, the target feed rate is recorded, and the position point is acquired at the target feed rate after the numerical control system is started. It is understandable that at this time, the target feed rate is not modified, and the target feed rate is backed up, that is, the feed rate curve is not updated during the stop process.

[0075] In order to better understand the above step A31, the process of step A31 is described in detail:

[0076] A31-1. Use the piecewise polynomial of formula (1) to obtain the feed rate curve.

[0077] It should be noted that this may be the process of updating the original feed rate curve, such as Figures 4 to 6 The graph shown.

[0078] Formula (1)

[0079] Among them, r0 is the starting feed rate, v mis the speed when the feed rate is 1, v0 is the starting speed; j s is a given parameter, t1, t2, t3 are the adjustment time of each stage of the feed rate curve segment, τ i , i=1,2,3 are local time coordinates, indicating the adjustment time with the starting point of each stage as the time zero point, r1,r2 are the feed rate values ​​at τ1=t1,τ2=t2 respectively; t represents the cumulative adjustment time with the starting point of the initial adjustment feed rate as the time zero point; n is the positive and negative sign judgment value, when r0≥r a When n=1, r0<r a When n=2, r a is the target feed rate;

[0080] In this embodiment, j s The value of can satisfy the processing of different plates. s When j is larger, the overall adjustment process takes a shorter time, which is suitable for processing actions that require rapid change of magnification, such as stop and emergency stop. s When it is smaller, the overall adjustment process takes longer, but the speed curve changes more slowly. This is suitable for processing scenarios that require a smoother change in the magnification.

[0081] A31-2, according to t, i.e., the cumulative time of feed rate adjustment in the planned interpolation information and the feed rate curve, obtaining the current interpolation time increment ΔT;

[0082] For example, the interpolation time increment is ΔT = T s *r(t), where T s To plan the interpolation period in the interpolation information;

[0083] In this embodiment, the feed rate accumulation time is the accumulation of adjustment time with the starting point of adjusting the feed rate as the time zero point.

[0084] A31-3. Obtain interpolation cumulative time information T+ΔT according to the interpolation time increment ΔT. That is, during interpolation in each interpolation cycle, the feed rate adjustment cumulative time is accumulated by one interpolation cycle.

[0085] The interpolation time increment ΔT can be understood as follows:

[0086] The interpolation process is the process of calculating the value through the interpolation function. The independent variable of the interpolation function is the interpolation cumulative time T. An increment of ΔT is accumulated during the interpolation of each planned interpolation cycle, and then the value of the interpolation function is calculated again. For example, if the interpolation function is y=2T (unit: mm), when T=5 (unit: s), the position coordinate is y=10 (unit: mm), and the next interpolation cycle assumes that the interpolation time increment ΔT=0.1 (unit: s), then the interpolation cumulative time T is accumulated by ΔT to obtain 5.1 (unit: s), so according to the interpolation function calculation, the position coordinate of the next interpolation cycle is y=10.2 (unit: mm).

[0087] A31-4. Obtain the position point according to the interpolation accumulated time information T+ΔT and the interpolation function.

[0088] For example, in a two-dimensional coordinate system, the position point is obtained according to formula (2);

[0089] Formula (2)

[0090] Among them, (x i ,y i ) is the interpolation position in the Cartesian coordinate system, f x are the x interpolation axis interpolation function, f y are the interpolation functions of the y interpolation axis respectively, and T is the cumulative interpolation time of the previous interpolation cycle.

[0091] The CNC system of this embodiment does not require re-speed planning and has a small amount of calculation, so that the real-time response of the feed rate adjustment is guaranteed, and the speed changes smoothly. By adjusting the input parameters of the maximum acceleration and the maximum acceleration and deceleration time, the feed rate curve is adjusted accordingly, so that the adjustment of the feed rate is suitable for different processing scenarios.

[0092] For better understanding, this embodiment illustrates the above control method through a specific example:

[0093] The given G code is as follows:

[0094] G00 X0 Y0

[0095] G01 X100 Y0 F12000.

[0096] That is, the processing length is 100mm, the feed speed is 200mm / s, and other parameters are set to the given maximum acceleration a by multiplier adjustment. max =10000mm / s 2 , Ratio adjustment parameter Maximum acceleration / deceleration time t A =0.05s, interpolation period T s = 0.001s, the processing section uses seven-stage S-shaped acceleration and deceleration. Figure 2 and Figure 3 As shown in the figure, the straight line starts with an acceleration stage with seven acceleration and deceleration stages, enters a uniform motion around 0.06s, and maintains at 200mm / s. At this time, the feed rate is 100%. Around 0.14s, the rate is adjusted from 100% to 200%, as shown in the figure. Figure 2 As shown in the figure, the speed smoothly transitions from 200 mm / s to 400 mm / s. Figure 3 The corresponding acceleration curve is continuous. At around 0.25s, the rate drops to 0.01%. Figure 2 The medium speed curve is smoothly reduced to 2mm / s, the acceleration changes smoothly, and the ratio around 0.92s is adjusted from 0.01% to 100%, corresponding to Figure 2 The medium speed changes from 2mm / s to 200mm / s and stabilizes. Figure 3 The acceleration is continuous near 0.92s, and the deceleration process is near 1.2s; the speed of the entire rate adjustment process is smooth, the acceleration changes continuously, and there is no need to re-plan and adjust the speed.

[0097] Figure 4 This is the feed rate curve when the feed rate is adjusted from 100% to 200% in this example. Figure 5 This is the feed rate curve when the feed rate is adjusted from 200% to 0.01%. Figure 6 The feed rate curve is as follows when the feed rate is adjusted from 0.01% to 100%. Figures 4 to 6 It can be seen that the feed rate curve is a piecewise polynomial curve and is smooth in the entire rate adjustment range.

[0098] Embodiment 3

[0099] like Figure 8 As shown, this embodiment also provides a numerical control system, including: a memory and a processor; the processor is used to execute the computer program stored in the memory to implement the steps of the feed rate control method in the numerical control system described in any of the above-mentioned embodiments 1 and 2.

[0100] A target feed rate acquisition module is used to receive a target feed rate input by a user;

[0101] A status signal acquisition module is used to obtain the status of the CNC system;

[0102] a processing module, configured to, when determining that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, obtain updated position points in the planned interpolation information according to a predefined rate update strategy based on basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, wherein the position points are position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that a servo drive device of the numerical control system performs a cutting operation according to the position points;

[0103] The predefined rate update strategy includes: obtaining the feed rate curve by piecewise polynomial method and calculating the interpolation cumulative time information, and then obtaining the position point in combination with the interpolation function in the planned interpolation information.

[0104] In practical applications, the above-mentioned CNC system also includes:

[0105] The sending module is used to send the position point to the servo system so that the servo drive device of the servo system performs a cutting operation according to the position point.

[0106] Specifically, the processing module can be used to: obtain the feed rate curve by using a piecewise polynomial method and calculate the interpolation cumulative time information, and then obtain the position point by combining the interpolation function in the planned interpolation information: for example, obtain the feed rate curve by using the piecewise polynomial of formula (1);

[0107] Formula (1)

[0108] According to the feed rate curve, the feed rate adjustment cumulative time t in the planned interpolation information is used to obtain the current interpolation time increment ΔT=T s *r(t); and according to the interpolation time increment ΔT, obtain the interpolation cumulative time information T+ΔT; and according to the interpolation cumulative time information T+ΔT and the interpolation function, obtain the position point.

[0109] The feed rate accumulation time in this embodiment is the accumulation of adjustment time with the starting point of adjusting the feed rate as the time zero point; during each interpolation cycle, the feed rate adjustment accumulation time accumulates one interpolation cycle.

[0110] When the above-mentioned CNC system adjusts the feed rate during the processing, the CNC system does not need to re-plan the speed, so that the real-time performance of the rate adjustment is guaranteed and the speed changes smoothly. That is, the rate curve is adjusted by adjusting the given parameters, so that the feed rate adjustment is suitable for different processing scenarios.

[0111] Embodiment 4

[0112] This embodiment also provides a control device, including: a memory and a processor; the processor is used to execute a computer program stored in the memory to implement the steps of the feed rate control method in the numerical control system described in any of the above-mentioned embodiments 1 and 2.

[0113] Specifically, the control device may include: at least one processor, at least one memory, at least one network interface and / or other user interface. The various components in the electronic device are coupled together through a bus system. It can be understood that the bus system is used to achieve connection and communication between these components. In addition to the data bus, the bus system also includes a power bus, a control bus and a status signal bus.

[0114] On the other hand, an embodiment of the present invention further provides a computer-readable storage medium for storing a computer program, which, when executed by a processor, implements the steps of the method for controlling the feed rate in a numerical control system in any of the above embodiments.

[0115] It should be noted that in the claims, any reference numerals placed between brackets shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. The invention may be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In the claims enumerating several means, several of these means may be embodied by the same hardware. The use of the words first, second, third, etc., is for convenience of expression only and does not indicate any order. These words may be understood as part of the component name.

[0116] In addition, it should be noted that, in the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0117] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments after knowing the basic creative concept. Therefore, the claims should be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0118] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention should also include these modifications and variations.

Claims

1. A method for controlling feed rate in a numerical control system, characterized in that: include: S10, the CNC system receives the target feed rate input by the user; S20, when the numerical control system determines that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, the updated position points in the planned interpolation information are obtained according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, according to a predefined rate update strategy, and the position points are the position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that the servo drive device of the numerical control system performs a cutting operation according to the position points; The predefined rate update strategy includes: using a piecewise polynomial method to obtain a feed rate curve and calculate interpolation cumulative time information, and then combining the interpolation function in the planned interpolation information to obtain the position point, specifically including: The piecewise polynomial of formula (1) is used to obtain the feed rate curve; Formula (1) ; in, is the starting feed rate, is the speed when the feed rate is 1, , is the starting speed; For given parameters, Adjust the elapsed time for each stage of the feed rate curve segment. is the local time coordinate, indicating the adjustment time with the starting point of each stage as the time zero point, They are , Feed rate value at ; Indicates the cumulative adjustment time starting from the initial adjustment feed rate as the time zero point; n is the positive and negative sign judgment value. hour, , hour, , is the target feed rate; According to the feed rate curve, the feed rate adjustment cumulative time in the planning interpolation information , get the current interpolation time increment ; The interpolation time increment is ,in To plan the interpolation period in the interpolation information; According to the interpolation time increment , get the interpolation cumulative time information ; According to the interpolation accumulation time information and the interpolation function in the planning interpolation information to obtain the position point; specifically comprising: obtaining the position point according to formula (2) in a two-dimensional coordinate system; Formula (2) ; in, is the interpolation position in the Cartesian coordinate system, They are the x-interpolation axis interpolation functions, They are the y interpolation axis interpolation functions, The cumulative interpolation time for the previous interpolation cycle.

2. The control method according to claim 1, characterized in that: The S20 includes: S201, the numerical control system determines whether the numerical control system is in a non-stop state based on the state identifier of the numerical control system, and if so, executes S202; S202, the numerical control system obtains the planned interpolation information of the current motion segment, and determines whether the target feed rate is the same as the feed rate at the current moment in the planned interpolation information. If they are the same, the target feed rate is ignored; otherwise, S203 is executed; S203: The numerical control system obtains updated position points in the planned interpolation information according to the basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate according to a predefined rate update strategy.

3. The control method according to claim 1, characterized in that: The control method further comprises: S30, the numerical control system sends the position point to a servo system connected to the numerical control system, so that a servo drive device of the servo system performs a cutting operation according to the position point.

4. The control method according to claim 1, characterized in that: The control method further comprises: S40: If the numerical control system is in a stopped state, the target feed rate is recorded, and the position point is acquired at the target feed rate after the numerical control system is started.

5. A numerical control system using the control method according to any one of claims 1 to 4, characterized in that: include: A target feed rate acquisition module is used to receive a target feed rate input by a user; A status signal acquisition module is used to obtain the status of the CNC system; a processing module, configured to, when determining that the feed rate at the current moment is different from the target feed rate and the numerical control system is in a non-stop state, obtain updated position points in the planned interpolation information according to a predefined rate update strategy based on basic parameters of the current interpolation cycle in the planned interpolation information and the target feed rate, wherein the position points are position coordinates of each node in the current motion segment parsed in the pattern to be processed, so that a servo drive device of the numerical control system performs a cutting operation according to the position points; The predefined rate update strategy includes: obtaining the feed rate curve by piecewise polynomial method and calculating the interpolation cumulative time information, and then obtaining the position point in combination with the interpolation function in the planned interpolation information.

6. The numerical control system according to claim 5, characterized in that: Also includes: The sending module is used to send the position point to the servo system so that the servo drive device of the servo system performs a cutting operation according to the position point.

7. A control device, characterized in that: include: A memory and a processor, wherein the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory and execute the steps of the feed rate control method in the numerical control system as described in any one of claims 1 to 4.

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