Reverse backlash compensation method and device, numerical control system and storage medium

Abstract

The invention discloses a reverse clearance compensation method and device, a numerical control system, a storage medium and a computer program product, and the method comprises the steps: determining target increment compensation time for carrying out reverse clearance increment compensation according to a reverse jump value of a motion axis of a numerical control machine tool and a preset function relation model of the reverse jump value and the increment compensation time; according to the reverse gap maximum value, the target increment compensation time and a preset formula, determining compensation values for performing reverse gap increment compensation on the motion shaft in different motion states; and performing increment compensation on the reverse gap according to the compensation value within the target increment compensation time. According to the scheme, reverse gap errors of different scenes are counteracted, the change rhythm is controlled through the target compensation time, mechanical impact and vibration of the machine tool are reduced, and operation stability and positioning precision are improved.

Description

Technical Field

[0001] This invention belongs to the field of CNC system technology, specifically relating to a backlash compensation method, device, CNC system, storage medium, and computer program product. Background Technology

[0002] In CNC machine tools with semi-closed-loop control systems, mechanical transmission chains commonly employ transmission mechanisms such as lead screw and nut pairs. However, due to factors such as machining accuracy, assembly errors, and long-term wear, a gap inevitably exists between the lead screw and nut. When the direction of motion of the axis changes (i.e., switching from positive to negative motion, or from negative to positive motion), the drive component must first overcome the aforementioned gap before it can drive the load component to follow the reverse motion. This results in the actual displacement lagging behind the commanded displacement. This gap error caused by the change in direction is called backlash.

[0003] Backlash, as a nonlinear error, severely restricts the positioning accuracy, repeatability, and contour tracking performance of CNC machine tools. Especially in machining scenarios requiring frequent bidirectional motion, it can lead to significant trajectory deviations, motion vibrations, and even drive step loss, directly affecting the dimensional accuracy and surface quality of machined parts, becoming a key bottleneck limiting high-precision machining by CNC machine tools. Therefore, backlash compensation for CNC systems is a necessary means to improve their motion accuracy and machining performance.

[0004] In practical applications, if the backlash compensation is too large, a sudden acceleration change will occur at the moment of direction switching, causing system impact. This will result in excessive backlash during the roundness test of the ballbar, which will exacerbate the trajectory error and reduce the machining accuracy.

[0005] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The purpose of this invention is to provide a backlash compensation method, device, CNC system, storage medium, and computer program product to solve the problem of impact caused by excessive backlash compensation in related solutions. By optimizing traditional full compensation into gradual incremental compensation, it can accurately offset backlash errors in different scenarios and control the change rhythm through target compensation time, thereby solving the machine tool impact problem caused by excessive backlash compensation, reducing machine tool mechanical impact and vibration, and improving operational stability and positioning accuracy.

[0007] This invention provides a backlash compensation method, comprising: obtaining the maximum backlash value and the backlash surge value of a CNC machine tool motion axis; determining a target incremental compensation time for backlash incremental compensation based on the backlash surge value and a preset functional relationship model between the backlash surge value and the incremental compensation time; determining a compensation value for backlash incremental compensation of the motion axis under different motion states based on the maximum backlash value, the target incremental compensation time, and a preset formula; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement; and incrementally compensating the backlash according to the compensation value within the target incremental compensation time.

[0008] In some implementations, the preset reverse impulse value and the incremental compensation time are modeled as a first-order linear function, expressed as: y = k·t c +b; where y is the reverse impulse value, t c Let b be the incremental compensation time, b be a constant term, and k be a coefficient.

[0009] In some implementations, when the motion state changes from rest to motion, the preset formula is: Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the start of the movement; when hour, Alternatively, when the motion state is from motion to rest, the preset formula is: Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k t represents the current moment in the motion; e The moment when the motion stops; when hour,

[0010] In some implementations, when the motion state is a change of direction during motion, the preset formula is: Where Δc is the compensation value; k yk is the direction coefficient before the changeover, when the motion axis before the changeover is in the positive direction. y =1, when the motion axis mentioned before the change is in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the reversal; t r This refers to the moment when the motion changes direction.

[0011] In some implementations, when the motion state is from stationary to moving or moving to stationary, the target total compensation value for incremental compensation is half of the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process stops and switches to stable compensation.

[0012] In some implementations, when the motion state is a reversal during motion, the target total compensation value for incremental compensation is the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process stops and switches to stable compensation.

[0013] In conjunction with the above method, another aspect of the present invention provides a backlash compensation device, comprising: an acquisition unit configured to acquire the maximum backlash value and the backlash surge value of a CNC machine tool motion axis; a calculation unit configured to determine a target incremental compensation time for performing backlash incremental compensation based on the backlash surge value and a preset functional relationship model between the backlash surge value and the incremental compensation time; the calculation unit is further configured to determine a compensation value for performing backlash incremental compensation on the motion axis under different motion states based on the maximum backlash value, the target incremental compensation time, and a preset formula; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement; and an execution unit configured to perform incremental compensation on the backlash according to the compensation value within the target incremental compensation time.

[0014] In conjunction with the above-mentioned device, the present invention further provides a numerical control system, including: the backlash compensation device described above.

[0015] In conjunction with the above method, the present invention further provides a storage medium comprising a stored program, wherein, when the program is executed, it controls the device in which the storage medium is located to perform the above-described backlash compensation method.

[0016] In conjunction with the above method, the present invention further provides a computer program product comprising a computer program that, when processed and executed, implements the steps of the above-described backlash compensation method.

[0017] The present invention determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation of the backlash is performed according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart of an embodiment of the backlash compensation method of the present invention;

[0021] Figure 2 This is a schematic diagram of an embodiment of the backlash compensation device of the present invention;

[0022] Figure 3 This is a schematic diagram of the backlash;

[0023] Figure 4 This is a graph showing the changes in the compensation value curve;

[0024] Figure 5 This is a flowchart illustrating another embodiment of the backlash compensation method.

[0025] Referring to the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0026] 1-Lead screw; 2-Worktable; 101-Acquisition unit; 102-Calculation unit; 103-Execution unit. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] According to an embodiment of the present invention, a method for compensating for backlash is provided, such as... Figure 1 The diagram shows a flowchart of an embodiment of the method of the present invention. The backlash compensation method may include steps S110 to S140.

[0029] In step S110, the maximum backlash and reverse surge value of the CNC machine tool motion axis are obtained.

[0030] The maximum backlash is the maximum amount of clearance that exists in the mechanical transmission chain of a CNC machine tool's motion axis when the direction of motion changes. Figure 3 The maximum clearance L formed between the lead screw 1 and the worktable 2 is the core error source that causes the actual displacement to lag behind the commanded displacement. The reverse jump value is the physical quantity corresponding to the instantaneous impact generated when the moving axis switches directions or changes state during the reverse backlash compensation process due to sudden changes in the compensation amount or unreasonable compensation rhythm (such as compensation being too fast). This physical quantity directly affects the smoothness of the machine tool movement and the machining accuracy.

[0031] The maximum backlash is the fundamental data for compensation, and its magnitude directly determines the upper limit of the compensation amount. The backlash value reflects the impact degree of the compensation process and is a key basis for determining the target incremental compensation time. The maximum backlash of the mechanical transmission chain can be obtained by testing the motion axis using the testing equipment of the CNC machine tool (such as a ballbar), and the backlash data under different compensation conditions can be recorded.

[0032] In step S120, the target incremental compensation time for performing reverse gap incremental compensation is determined based on the reverse jump value and the preset functional relationship model between the reverse jump value and the incremental compensation time.

[0033] Incremental compensation time is the total time required to complete incremental compensation of the backlash. It is used to control the rhythm of the compensation amount's change and avoid excessive instantaneous compensation amount causing excessive backlash. There is a correlation between the backlash value and the incremental compensation time: if the compensation time is too short, sudden changes in the compensation amount can easily lead to a large backlash; if the compensation time is too long, it will reduce the response speed. A target incremental compensation time that balances stability and efficiency can be found through a preset model.

[0034] In some implementations, the functional relationship between the preset reverse impulse value and the incremental compensation time is a first-order linear function model, expressed as:

[0035] y = k·t c +b;

[0036] Where y is the reverse impulse value, t cLet be the incremental compensation time, b be a constant term, and k be a coefficient. The physical meaning of coefficient k is the influence coefficient of incremental compensation time on the reverse surge value. If k is negative, it indicates that as the incremental compensation time increases, the reverse surge value will decrease accordingly, which is consistent with the actual compensation logic (extending the compensation time can reduce the impact). The constant term b reflects the basic reverse surge value generated by the mechanical characteristics of the CNC machine tool when there is no additional incremental compensation time. This value is a basic parameter that needs to be considered when calculating the target incremental compensation time.

[0037] In CNC machine tool backlash compensation scenarios, when other influencing factors (such as feed rate and maximum backlash value) are fixed, the backlash jump value exhibits an approximately linear relationship with the incremental compensation time: the longer the incremental compensation time, the smoother the change in compensation amount, and the smaller the backlash jump value; conversely, the shorter the incremental compensation time, the more drastic the change in compensation amount, and the larger the backlash jump value. Based on this pattern, choosing a first-order linear function model can accurately and concisely describe the relationship between the two, facilitating subsequent mathematical calculations to determine the optimal incremental compensation time.

[0038] The pre-set process for this first-order linear function relationship model is as follows: Technicians first conduct multiple sets of backlash compensation experiments with different incremental compensation times on a specific CNC machine tool, under test conditions of fixed feed speed and fixed maximum backlash value. For example, the incremental compensation time t is set separately. c Let t1, t2, t3...t n The corresponding reverse impulse values ​​y1, y2, y3...yn generated by the motion axis in each experiment are recorded.

[0039] The multiple sets of (t) obtained c Substitute the data (y) into the first-order linear function relationship model, and use data fitting methods (such as the least squares method) to calculate the coefficient k and the constant term b. By fitting, the error between the reverse jump value calculated by the model and the reverse jump value tested in the actual test is minimized, and finally the first-order linear function relationship model that conforms to the characteristics of the CNC machine tool is determined.

[0040] By using a first-order linear function model, the fuzzy relationship between the two key parameters, reverse impulse value and incremental compensation time, is transformed into a clear mathematical relationship, avoiding the subjectivity and inaccuracy of relying on experience to judge the compensation time. The mathematical form of the first-order linear function model is simple and computationally easy. In actual operation, the CNC system can quickly calculate the corresponding incremental compensation time based on the reverse impulse value according to the model without complex calculation logic, ensuring the real-time performance of compensation control. For CNC machine tools of the same type and specifications, the linear correlation between the reverse impulse value and the incremental compensation time is consistent. Therefore, this first-order linear function model can be reused in similar equipment. Only the coefficient k and the constant term b need to be fine-tuned based on the test data of a single machine, reducing the cost and difficulty of model establishment.

[0041] In step S130, the compensation value for backlash increment compensation of the motion axis under different motion states is determined according to the maximum backlash value, the target incremental compensation time, and the preset formula; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement.

[0042] The backlash manifests differently under different motion conditions (e.g., overcoming the initial backlash is required when moving from a standstill, and canceling the bidirectional backlash when reversing direction), so compensation values ​​need to be calculated accordingly.

[0043] The motion states include three typical scenarios: from stationary to moving, from moving to stationary, and changing direction during motion. In the stationary to moving scenario, the motion axis changes from a stationary state to positive or negative motion; in the moving to stationary scenario, the motion axis changes from positive or negative motion to a stationary state; in the changing direction during motion scenario, the motion axis changes from positive to negative or from negative to positive during motion.

[0044] The compensation value refers to the dynamic adjustment amount applied to offset backlash error. It changes in real time with the motion state and time, and is the core parameter of incremental compensation. For a stationary-to-moving scenario, the compensation value starts from 0 and increases linearly to L / 2 over time. For a moving-to-stationary scenario, the compensation value decreases linearly from L / 2 to 0. For a reversing scenario during motion, the compensation value switches from L / 2 in the original direction to -L / 2 in the opposite direction. Here, L represents the maximum backlash value.

[0045] In some implementations, when the motion state changes from rest to motion, the preset formula is:

[0046]

[0047] Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, ky =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the start of the movement; when hour,

[0048] When the motion axis of a CNC machine tool is stationary, the meshing state of its mechanical transmission chain exhibits an initial backlash lag, which is approximately half of the maximum backlash value L. When the motion axis switches from stationary to forward or reverse motion, directly applying full compensation would cause a sudden change in the compensation amount, triggering a momentary impact on the motion axis. However, by using linear incremental compensation (the compensation value gradually increases from 0 to L / 2), the process of eliminating the initial backlash lag can be matched. At the same time, by controlling the growth rhythm in conjunction with the target incremental compensation time, the backlash error can be accurately offset while avoiding reverse surges.

[0049] The compensation process from a stationary to a moving scene is as follows: First, determine the maximum backlash, target increment compensation time, and direction coefficient for that scene; then, determine the time (t) at which the start command is received from the motion axis. k Starting at t=0), the CNC system calculates the compensation value in real time according to this formula. k As time gradually increases, the compensation value Δc increases linearly from 0; when the motion starts at the current time t... k Exceeding the target incremental compensation time t c Half of (i.e.) To avoid the compensation value exceeding the target total compensation value L / 2, the CNC system forcibly... At this point, the system enters a stable compensation phase until the motion axis switches to another motion state. For example... Figure 4 As shown in the startup phase, during positive startup, the compensation value gradually increases from 0 to L / 2 with the interpolation time; during negative startup, the compensation value gradually decreases from 0 to -L / 2 with the interpolation time.

[0050] In some implementations, when the motion state is from motion to rest, the preset formula is:

[0051]

[0052] Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k t represents the current moment in the motion; e The moment when the motion stops; when hour,

[0053] When a CNC machine tool's motion axis is in a stable state, the compensation value needs to be maintained at L / 2 to continuously offset the backlash error. When the motion axis switches from motion to rest, the backlash requirement of the mechanical transmission chain gradually decreases. If the compensation value remains at L / 2, it will lead to over-compensation of the backlash at the moment of rest, causing an impact. Therefore, linear incremental compensation (the compensation value gradually decreases from L / 2 to 0) is required, combined with the target incremental compensation time to control the decreasing rhythm, so that the compensation value is synchronized with the change in backlash requirement, ensuring a smooth stop of the motion axis.

[0054] The compensation process for a moving-to-stationary scenario is as follows: determine the maximum backlash, target incremental compensation time, direction coefficient, and motion stop time for that scenario; and the preset time point before receiving the stop command from the motion axis (i.e., At the start, the CNC system calculates the compensation value in real time according to the formula. At this point, t... k Gradually approaching t e The compensation value Δc decreases linearly starting from L / 2. At the current time t during the motion... k Less than the time t when the motion stops e Compensation time t for target increment c Half of the difference (i.e.) The motion axis is still in a stable motion phase and does not require a decrease in compensation value. Therefore, the CNC system forces the motion axis to remain in a stable motion phase. Maintain a stable compensation state. For example... Figure 4 As shown in the stopping phase, during positive stopping, the compensation value gradually decreases from L / 2 to 0 with the interpolation time; during negative stopping, the compensation value gradually increases from -L / 2 to 0 with the interpolation time.

[0055] To address the characteristics of clearance errors in both stationary-to-moving and moving-to-stationary scenarios, compensation formulas with linear growth and linear decrease are designed respectively. This ensures that the changes in compensation values ​​are completely synchronized with the changes in clearance requirements of the mechanical transmission chain, effectively offsetting the problems of initial clearance lag and overcompensation of stopping clearance, and significantly improving the positioning accuracy of the moving axis.

[0056] In some implementations, when the motion state is a change of direction during motion, the preset formula is:

[0057]

[0058] Where Δc is the compensation value; k y k is the direction coefficient before the changeover, when the motion axis before the changeover is in the positive direction. y =1, when the motion axis mentioned before the change is in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t cThe target incremental compensation time; t k The current moment after the reversal; t r This refers to the moment when the motion changes direction.

[0059] During the stable motion phase of the motion shaft (before reversal), the compensation value must remain at L / 2 of the original direction (e.g., L / 2 for forward motion and -L / 2 for reverse motion) to continuously offset the backlash error. When the motion shaft begins to reverse, the meshing state of the mechanical transmission chain switches from the original direction to the reverse direction, and the direction of the backlash error reverses accordingly. At this time, the compensation value needs to gradually transition from "L / 2 of the original direction" to "-L / 2 after reversal" (the total change is L). If the compensation value is abruptly changed (e.g., from L / 2 to -L / 2 instantaneously), it will cause the motion shaft to be subjected to a momentary impact, triggering a reverse jump. However, through linear incremental compensation, the compensation value can change smoothly over time, accurately offsetting the backlash error during the reversal process while avoiding impact.

[0060] The compensation process in a motion-changing scenario is as follows:

[0061] Before the reversing motion begins, the CNC system first determines the maximum backlash, the target increment compensation time, and the direction coefficient before reversing (determined based on the target direction before reversing, taking 1 for positive and -1 for negative) for the given scenario, and records the reversing moment. The current time t after the reversal is... k This refers to the time elapsed from the moment the motion axis officially begins its reversal action (i.e., the instant the motion direction begins to change) to the present. It is a dynamically changing time variable, used to calculate the compensation value at every instant during the reversal process in real time, driving the compensation value to adjust smoothly over time; the motion reversal moment t r The precise moment when the control system issues a reversing command and the motion axis begins to switch from its original direction to the opposite direction is the time reference point for the reversing process.

[0062] From the reversal time t r Start (at this time t) k =t r The CNC system updates t according to the interpolation cycle (e.g., every millisecond). k And substitute it into the formula to calculate the real-time compensation value Δc:

[0063] Initial time of commutation (t) k =t r ): That is, the compensation value is the stable compensation amount in the original direction, ensuring that the compensation value matches the current clearance error at the start of the reversal.

[0064] During the commutation process (t r <t k <t r +t c ): With tk Increase As the value gradually increases, the compensation value Δc decreases linearly (k y When the value is equal to 1, the compensation value continues to approach the stable compensation amount after the commutation.

[0065] End of commutation time (t) k =t r +t c ): That is, the compensation value reaches the stable compensation amount after the commutation. After that, the CNC system stops incremental compensation and keeps the compensation value unchanged.

[0066] The changes in compensation values ​​during direction-changing scenarios in motion are as follows: Figure 4 As shown in the reversal phase, during the reversal from positive to negative direction, the compensation value gradually decreases from L / 2 to -L / 2; during the reversal from negative to positive direction, the compensation value gradually increases from -L / 2 to L / 2.

[0067] The formula achieves linear incremental changes in the compensation value, avoiding instantaneous impact caused by sudden changes in the compensation value, significantly reducing the reverse jump of the motion axis, ensuring the smooth operation of the machine tool, and reducing the wear of mechanical parts.

[0068] At step S140, during the target incremental compensation time, incremental compensation is performed on the backlash according to the compensation value.

[0069] Incremental compensation refers to the gradual change of the compensation value over time, rather than applying the full amount instantaneously. By controlling the target incremental compensation time, a smooth transition in the compensation process is achieved. Specifically, after determining the target incremental compensation time and compensation value, the CNC system adjusts the output command in real time according to the compensation value, so that the compensation value gradually reaches the target value from the initial value (e.g., from 0 to L / 2 when moving from a stationary state), thus completing the dynamic cancellation of backlash.

[0070] This solution calculates compensation values ​​by state division, accurately matching the backlash characteristics under different motion scenarios, reducing positioning errors and hysteresis; and controls the compensation rhythm by controlling the target incremental compensation time to avoid sudden changes in compensation amount, making the motion axis run more smoothly.

[0071] In some embodiments, the method further includes: when the motion state is from stationary to motion or from motion to stationary, the target total compensation value for incremental compensation is half of the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process is stopped and switched to stable compensation, and the stable compensation value in the stationary to motion scenario is... The stability compensation value for a motion-to-stationary motion scenario is 0.

[0072] In a stationary-to-moving scenario, when the moving axis is stationary, there is an initial backlash of L / 2 in the mechanical transmission chain. The compensation value needs to be increased to L / 2 to offset this backlash. In a moving-to-stationary scenario, when the moving axis is in stable motion, the compensation value is already L / 2. Before stopping, the compensation value needs to be gradually reduced until the backlash requirement disappears.

[0073] The core of incremental compensation is a smooth transition, avoiding shocks caused by sudden changes in compensation values. However, incremental compensation cannot continue indefinitely. When the compensation value reaches L / 2, it has completely offset the gap error of the current scene. Continuing to increment will lead to overcompensation. Therefore, incremental compensation needs to be stopped and switched to stable compensation. By using a fixed compensation value to maintain accuracy, the dual goals of smooth transition and stable accuracy can be achieved.

[0074] After entering the stable compensation phase, the CNC system will fix the compensation value to [value]. If the axis of motion is in the positive direction, k y =1, the stability compensation value is If the motion axis is in the negative direction, k y =-1, the stability compensation value is

[0075] By clearly defining the target total compensation value as L / 2, we can avoid situations where there is insufficient or excessive compensation during the incremental compensation process, ensuring that the gap errors in both scenarios are completely offset. After switching to stable compensation, the compensation value remains fixed, which not only eliminates the potential impact risk of the incremental process, but also maintains the accuracy continuously.

[0076] In some embodiments, the method further includes: when the motion state is a reversal during motion, the target total compensation value for incremental compensation is the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process is stopped and switched to stable compensation, where the compensation value for stable compensation is...

[0077] When the motion shaft reverses direction, the direction of the backlash error reverses: before reversing, the compensation value needs to maintain "L / 2 of the original direction" to offset the backlash in the original direction; during reversal, the mechanical transmission chain needs to switch from "meshing in the original direction" to "meshing in the opposite direction," and the backlash error changes from "L / 2 of the original direction" to "L / 2 of the opposite direction." The compensation value needs to transition from "L / 2 of the original direction" to "L / 2 of the opposite direction," and the total change is exactly equal to the maximum backlash value L. Therefore, setting the target total compensation value of incremental compensation to L can accurately cover all backlash errors during the reversal process, avoiding insufficient or excessive compensation.

[0078] When the total change in compensation value reaches L, the gap error during the commutation process has been completely offset, and the stable compensation phase needs to be entered. If the direction before commutation is positive (k... y=1), after commutation it becomes negative, requiring a compensation value of "-L / 2"; if before commutation it is negative (k y =-1), after the reversal it becomes positive, and a compensation value of "L / 2" needs to be applied.

[0079] The target total compensation value of incremental compensation is set to the maximum value of the backlash, which perfectly matches the total change requirement of the compensation value during the reversal process. This can completely offset the backlash error when the mechanical transmission chain reverses, and significantly improve the reversal positioning accuracy of the motion shaft. The linear change of the compensation value is achieved through incremental compensation, avoiding the instantaneous impact caused by the sudden change of the compensation value. When the compensation value reaches the target total compensation value, it immediately switches to stable compensation to prevent the compensation value from exceeding the required range.

[0080] Figure 5 A flowchart illustrating another embodiment of the backlash compensation method is shown below. Figure 5 As shown, the method includes:

[0081] Step 1: After the CNC machine tool is started, the movement direction of the CNC machine tool's motion axis is detected. When the movement direction is positive, the compensation value ΔC is increased to L / 2 and maintained at L / 2; when the movement direction is negative, the compensation value ΔC is increased from 0 to -L / 2 and maintained at -L / 2.

[0082] Step 2: After detecting the reversal of the motion axis, if it is a positive to negative direction, the compensation value ΔC is increased to -L / 2; if it is a negative to positive direction, the compensation value ΔC is increased to L / 2.

[0083] Step 3: After the motion axis stops moving, the compensation value ΔC is incremented to 0.

[0084] The direction of motion of a motion axis can be determined from the position data sent from the previous interpolation cycle and the current interpolation cycle of the CNC system. Taking the X-axis as an example, let the position value sent from the previous interpolation cycle be x. i-1 The current interpolation period is x. i ;x i -x i-1 If the x-axis value is >0, the current movement is in the positive direction; otherwise, it is in the negative direction. i -x i-1 When the value is 0, the current state is stationary. The detection threshold for reversal can be set to 0.0001mm. When the position difference is less than 0.0001mm, it is not considered a reversal.

[0085] The technical solution of this embodiment determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation is performed on the backlash according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0086] According to an embodiment of the present invention, a backlash compensation device corresponding to the backlash compensation method is also provided. See also Figure 2 The diagram shows a structural schematic of an embodiment of the device of the present invention. The backlash compensation device may include: an acquisition unit 101, a calculation unit 102, and an execution unit 103.

[0087] The acquisition unit 101 is configured to acquire the maximum backlash and the reverse surge value of the CNC machine tool motion axis.

[0088] The maximum backlash is the maximum amount of clearance that exists in the mechanical transmission chain of a CNC machine tool's motion axis when the direction of motion changes. Figure 3 The maximum clearance L formed between the lead screw 1 and the worktable 2 is the core error source that causes the actual displacement to lag behind the commanded displacement. The reverse jump value is the physical quantity corresponding to the instantaneous impact generated when the moving axis switches directions or changes state during the reverse backlash compensation process due to sudden changes in the compensation amount or unreasonable compensation rhythm (such as compensation being too fast). This physical quantity directly affects the smoothness of the machine tool movement and the machining accuracy.

[0089] The maximum backlash is the fundamental data for compensation, and its magnitude directly determines the upper limit of the compensation amount. The backlash value reflects the impact degree of the compensation process and is a key basis for determining the target incremental compensation time. The maximum backlash of the mechanical transmission chain can be obtained by testing the motion axis using the testing equipment of the CNC machine tool (such as a ballbar), and the backlash data under different compensation conditions can be recorded.

[0090] The calculation unit 102 is configured to determine the target incremental compensation time for performing reverse gap incremental compensation based on the reverse jump value and a preset functional relationship model between the reverse jump value and the incremental compensation time.

[0091] Incremental compensation time is the total time required to complete incremental compensation of the backlash. It is used to control the rhythm of the compensation amount's change and avoid excessive instantaneous compensation amount causing excessive backlash. There is a correlation between the backlash value and the incremental compensation time: if the compensation time is too short, sudden changes in the compensation amount can easily lead to a large backlash; if the compensation time is too long, it will reduce the response speed. A target incremental compensation time that balances stability and efficiency can be found through a preset model.

[0092] In some implementations, the functional relationship between the preset reverse impulse value and the incremental compensation time is a first-order linear function model, expressed as:

[0093] y = k·t c +b;

[0094] Where y is the reverse impulse value, t c Let be the incremental compensation time, b be a constant term, and k be a coefficient. The physical meaning of coefficient k is the influence coefficient of incremental compensation time on the reverse surge value. If k is negative, it indicates that as the incremental compensation time increases, the reverse surge value will decrease accordingly, which is consistent with the actual compensation logic (extending the compensation time can reduce the impact). The constant term b reflects the basic reverse surge value generated by the mechanical characteristics of the CNC machine tool when there is no additional incremental compensation time. This value is a basic parameter that needs to be considered when calculating the target incremental compensation time.

[0095] In CNC machine tool backlash compensation scenarios, when other influencing factors (such as feed rate and maximum backlash value) are fixed, the backlash jump value exhibits an approximately linear relationship with the incremental compensation time: the longer the incremental compensation time, the smoother the change in compensation amount, and the smaller the backlash jump value; conversely, the shorter the incremental compensation time, the more drastic the change in compensation amount, and the larger the backlash jump value. Based on this pattern, choosing a first-order linear function model can accurately and concisely describe the relationship between the two, facilitating subsequent mathematical calculations to determine the optimal incremental compensation time.

[0096] The pre-set process for this first-order linear function relationship model is as follows: Technicians first conduct multiple sets of backlash compensation experiments with different incremental compensation times on a specific CNC machine tool, under test conditions of fixed feed speed and fixed maximum backlash value. For example, the incremental compensation time t is set separately. c Let t1, t2, t3...t n The corresponding reverse impulse values ​​y1, y2, y3...yn generated by the motion axis in each experiment are recorded.

[0097] The multiple sets of (t) obtained cSubstitute the data (y) into the first-order linear function relationship model, and use data fitting methods (such as the least squares method) to calculate the coefficient k and the constant term b. By fitting, the error between the reverse jump value calculated by the model and the reverse jump value tested in the actual test is minimized, and finally the first-order linear function relationship model that conforms to the characteristics of the CNC machine tool is determined.

[0098] By using a first-order linear function model, the fuzzy relationship between the two key parameters, reverse impulse value and incremental compensation time, is transformed into a clear mathematical relationship, avoiding the subjectivity and inaccuracy of relying on experience to judge the compensation time. The mathematical form of the first-order linear function model is simple and computationally easy. In actual operation, the CNC system can quickly calculate the corresponding incremental compensation time based on the reverse impulse value according to the model without complex calculation logic, ensuring the real-time performance of compensation control. For CNC machine tools of the same type and specifications, the linear correlation between the reverse impulse value and the incremental compensation time is consistent. Therefore, this first-order linear function model can be reused in similar equipment. Only the coefficient k and the constant term b need to be fine-tuned based on the test data of a single machine, reducing the cost and difficulty of model establishment.

[0099] The calculation unit 102 is further configured to determine the compensation value for backlash incremental compensation of the motion axis under different motion states based on the maximum backlash value, the target incremental compensation time, and a preset formula; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement.

[0100] The backlash manifests differently under different motion conditions (e.g., overcoming the initial backlash is required when moving from a standstill, and canceling the bidirectional backlash when reversing direction), so compensation values ​​need to be calculated accordingly.

[0101] The motion states include three typical scenarios: from stationary to moving, from moving to stationary, and changing direction during motion. In the stationary to moving scenario, the motion axis changes from a stationary state to positive or negative motion; in the moving to stationary scenario, the motion axis changes from positive or negative motion to a stationary state; in the changing direction during motion scenario, the motion axis changes from positive to negative or from negative to positive during motion.

[0102] The compensation value refers to the dynamic adjustment amount applied to offset backlash error. It changes in real time with the motion state and time, and is the core parameter of incremental compensation. For a stationary-to-moving scenario, the compensation value starts from 0 and increases linearly to L / 2 over time. For a moving-to-stationary scenario, the compensation value decreases linearly from L / 2 to 0. For a reversing scenario during motion, the compensation value switches from L / 2 in the original direction to -L / 2 in the opposite direction. Here, L represents the maximum backlash value.

[0103] In some implementations, when the motion state changes from rest to motion, the preset formula is:

[0104]

[0105] Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the start of the movement; when hour,

[0106] When the motion axis of a CNC machine tool is stationary, the meshing state of its mechanical transmission chain exhibits an initial backlash lag, which is approximately half of the maximum backlash value L. When the motion axis switches from stationary to forward or reverse motion, directly applying full compensation would cause a sudden change in the compensation amount, triggering a momentary impact on the motion axis. However, by using linear incremental compensation (the compensation value gradually increases from 0 to L / 2), the process of eliminating the initial backlash lag can be matched. At the same time, by controlling the growth rhythm in conjunction with the target incremental compensation time, the backlash error can be accurately offset while avoiding reverse surges.

[0107] The compensation process from a stationary to a moving scene is as follows: First, determine the maximum backlash, target increment compensation time, and direction coefficient for that scene; then, determine the time (t) at which the start command is received from the motion axis. k Starting at t=0), the CNC system calculates the compensation value in real time according to this formula. k As time gradually increases, the compensation value Δc increases linearly from 0; when the motion starts at the current time t... k Exceeding the target incremental compensation time t c Half of (i.e.) To avoid the compensation value exceeding the target total compensation value L / 2, the CNC system forcibly... At this point, the system enters a stable compensation phase until the motion axis switches to another motion state. For example... Figure 4 As shown in the startup phase, during positive startup, the compensation value gradually increases from 0 to L / 2 with the interpolation time; during negative startup, the compensation value gradually decreases from 0 to -L / 2 with the interpolation time.

[0108] In some implementations, when the motion state is from motion to rest, the preset formula is:

[0109]

[0110] Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction.y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k t represents the current moment in the motion; e The moment when the motion stops; when hour,

[0111] When a CNC machine tool's motion axis is in a stable state, the compensation value needs to be maintained at L / 2 to continuously offset the backlash error. When the motion axis switches from motion to rest, the backlash requirement of the mechanical transmission chain gradually decreases. If the compensation value remains at L / 2, it will lead to over-compensation of the backlash at the moment of rest, causing an impact. Therefore, linear incremental compensation (the compensation value gradually decreases from L / 2 to 0) is required, combined with the target incremental compensation time to control the decreasing rhythm, so that the compensation value is synchronized with the change in backlash requirement, ensuring a smooth stop of the motion axis.

[0112] The compensation process for a moving-to-stationary scenario is as follows: determine the maximum backlash, target incremental compensation time, direction coefficient, and motion stop time for that scenario; and the preset time point before receiving the stop command from the motion axis (i.e., At the start, the CNC system calculates the compensation value in real time according to the formula. At this point, t... k Gradually approaching t e The compensation value Δc decreases linearly starting from L / 2. At the current time t during the motion... k Less than the time t when the motion stops e Compensation time t for target increment c Half of the difference (i.e.) The motion axis is still in a stable motion phase and does not require a decrease in compensation value. Therefore, the CNC system forces the motion axis to remain in a stable motion phase. Maintain a stable compensation state. For example... Figure 4 As shown in the stopping phase, during positive stopping, the compensation value gradually decreases from L / 2 to 0 with the interpolation time; during negative stopping, the compensation value gradually increases from -L / 2 to 0 with the interpolation time.

[0113] To address the characteristics of clearance errors in both stationary-to-moving and moving-to-stationary scenarios, compensation formulas with linear growth and linear decrease are designed respectively. This ensures that the changes in compensation values ​​are completely synchronized with the changes in clearance requirements of the mechanical transmission chain, effectively offsetting the problems of initial clearance lag and overcompensation of stopping clearance, and significantly improving the positioning accuracy of the moving axis.

[0114] In some implementations, when the motion state is a change of direction during motion, the preset formula is:

[0115]

[0116] Where Δc is the compensation value; k y k is the direction coefficient before the changeover, when the motion axis before the changeover is in the positive direction. y =1, when the motion axis mentioned before the change is in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the reversal; t r This refers to the moment when the motion changes direction.

[0117] During the stable motion phase of the motion shaft (before reversal), the compensation value must remain at L / 2 of the original direction (e.g., L / 2 for forward motion and -L / 2 for reverse motion) to continuously offset the backlash error. When the motion shaft begins to reverse, the meshing state of the mechanical transmission chain switches from the original direction to the reverse direction, and the direction of the backlash error reverses accordingly. At this time, the compensation value needs to gradually transition from "L / 2 of the original direction" to "-L / 2 after reversal" (the total change is L). If the compensation value is abruptly changed (e.g., from L / 2 to -L / 2 instantaneously), it will cause the motion shaft to be subjected to a momentary impact, triggering a reverse jump. However, through linear incremental compensation, the compensation value can change smoothly over time, accurately offsetting the backlash error during the reversal process while avoiding impact.

[0118] The compensation process in a motion-changing scenario is as follows:

[0119] Before the reversing motion begins, the CNC system first determines the maximum backlash, the target increment compensation time, and the direction coefficient before reversing (determined based on the target direction before reversing, taking 1 for positive and -1 for negative) for the given scenario, and records the reversing moment. The current time t after the reversal is... k This refers to the time elapsed from the moment the motion axis officially begins its reversal action (i.e., the instant the motion direction begins to change) to the present. It is a dynamically changing time variable, used to calculate the compensation value at every instant during the reversal process in real time, driving the compensation value to adjust smoothly over time; the motion reversal moment t r The precise moment when the control system issues a reversing command and the motion axis begins to switch from its original direction to the opposite direction is the time reference point for the reversing process.

[0120] From the reversal time t r Start (at this time t) k =t r The CNC system updates t according to the interpolation cycle (e.g., every millisecond). k And substitute it into the formula to calculate the real-time compensation value Δc:

[0121] Initial time of commutation (t) k =t r ): That is, the compensation value is the stable compensation amount in the original direction, ensuring that the compensation value matches the current clearance error at the start of the reversal.

[0122] During the commutation process (t r <t k <t r +t c ): With t k Increase As the value gradually increases, the compensation value Δc decreases linearly (k y =1), the compensation value continues to approach the stable compensation amount after the commutation.

[0123] End of commutation time (t) k =t r +t c ): That is, the compensation value reaches the stable compensation amount after the commutation. After that, the CNC system stops incremental compensation and keeps the compensation value unchanged.

[0124] The changes in compensation values ​​during direction-changing scenarios in motion are as follows: Figure 4 As shown in the reversal phase, during the reversal from positive to negative direction, the compensation value gradually decreases from L / 2 to -L / 2; during the reversal from negative to positive direction, the compensation value gradually increases from -L / 2 to L / 2.

[0125] The formula achieves linear incremental changes in the compensation value, avoiding instantaneous impact caused by sudden changes in the compensation value, significantly reducing the reverse jump of the motion axis, ensuring the smooth operation of the machine tool, and reducing the wear of mechanical parts.

[0126] The execution unit 103 is configured to perform incremental compensation on the backlash according to the compensation value within the target incremental compensation time.

[0127] Incremental compensation refers to the gradual change of the compensation value over time, rather than applying the full amount instantaneously. By controlling the target incremental compensation time, a smooth transition in the compensation process is achieved. Specifically, after determining the target incremental compensation time and compensation value, the CNC system adjusts the output command in real time according to the compensation value, so that the compensation value gradually reaches the target value from the initial value (e.g., from 0 to L / 2 when moving from a stationary state), thus completing the dynamic cancellation of backlash.

[0128] This solution calculates compensation values ​​by state division, accurately matching the backlash characteristics under different motion scenarios, reducing positioning errors and hysteresis; and controls the compensation rhythm by controlling the target incremental compensation time to avoid sudden changes in compensation amount, making the motion axis run more smoothly.

[0129] In some embodiments, the execution unit 103 is further configured to: when the motion state is from stationary to moving or moving to stationary, the target total compensation value for incremental compensation is half of the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process is stopped and switched to stable compensation; the compensation value for stable compensation is...

[0130] In a stationary-to-moving scenario, when the moving axis is stationary, there is an initial backlash of L / 2 in the mechanical transmission chain. The compensation value needs to be increased to L / 2 to offset this backlash. In a moving-to-stationary scenario, when the moving axis is in stable motion, the compensation value is already L / 2. Before stopping, the compensation value needs to be gradually reduced until the backlash requirement disappears.

[0131] The core of incremental compensation is a smooth transition, avoiding shocks caused by sudden changes in compensation values. However, incremental compensation cannot continue indefinitely. When the compensation value reaches L / 2, it has completely offset the gap error of the current scene. Continuing to increment will lead to overcompensation. Therefore, incremental compensation needs to be stopped and switched to stable compensation. By using a fixed compensation value to maintain accuracy, the dual goals of smooth transition and stable accuracy can be achieved.

[0132] After entering the stable compensation phase, the CNC system will fix the compensation value to [value]. If the axis of motion is in the positive direction, k y =1, the stability compensation value is If the motion axis is in the negative direction, k y =-1, the stability compensation value is

[0133] By clearly defining the target total compensation value as L / 2, we can avoid situations where there is insufficient or excessive compensation during the incremental compensation process, ensuring that the gap errors in both scenarios are completely offset. After switching to stable compensation, the compensation value remains fixed, which not only eliminates the potential impact risk of the incremental process, but also maintains the accuracy continuously.

[0134] In some embodiments, the execution unit 103 is further configured to: when the motion state is a reversal during motion, the target total compensation value for incremental compensation is the maximum value of the backlash; when the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process is stopped and switched to stable compensation; the compensation value for stable compensation is...

[0135] When the motion shaft reverses direction, the direction of the backlash error reverses: before reversing, the compensation value needs to maintain "L / 2 of the original direction" to offset the backlash in the original direction; during reversal, the mechanical transmission chain needs to switch from "meshing in the original direction" to "meshing in the opposite direction," and the backlash error changes from "L / 2 of the original direction" to "L / 2 of the opposite direction." The compensation value needs to transition from "L / 2 of the original direction" to "L / 2 of the opposite direction," and the total change is exactly equal to the maximum backlash value L. Therefore, setting the target total compensation value of incremental compensation to L can accurately cover all backlash errors during the reversal process, avoiding insufficient or excessive compensation.

[0136] When the total change in compensation value reaches L, the gap error during the commutation process has been completely offset, and the stable compensation phase needs to be entered. If the direction before commutation is positive (k... y =1), after commutation it becomes negative, requiring a compensation value of "-L / 2"; if before commutation it is negative (k y =-1), after the reversal it becomes positive, and a compensation value of "L / 2" needs to be applied.

[0137] The target total compensation value of incremental compensation is set to the maximum value of the backlash, which perfectly matches the total change requirement of the compensation value during the reversal process. This can completely offset the backlash error when the mechanical transmission chain reverses, and significantly improve the reversal positioning accuracy of the motion shaft. The linear change of the compensation value is achieved through incremental compensation, avoiding the instantaneous impact caused by the sudden change of the compensation value. When the compensation value reaches the target total compensation value, it immediately switches to stable compensation to prevent the compensation value from exceeding the required range.

[0138] Figure 5 A flowchart illustrating another embodiment of the backlash compensation method is shown below. Figure 5 As shown, the method includes:

[0139] Step 1: After the CNC machine tool is started, the movement direction of the CNC machine tool's motion axis is detected. When the movement direction is positive, the compensation value ΔC is increased to L / 2 and maintained at L / 2; when the movement direction is negative, the compensation value ΔC is increased from 0 to -L / 2 and maintained at -L / 2.

[0140] Step 2: After detecting the reversal of the motion axis, if it is a positive to negative direction, the compensation value ΔC is increased to -L / 2; if it is a negative to positive direction, the compensation value ΔC is increased to L / 2.

[0141] Step 3: After the motion axis stops moving, the compensation value ΔC is incremented to 0.

[0142] The direction of motion of a motion axis can be determined from the position data sent from the previous interpolation cycle and the current interpolation cycle of the CNC system. Taking the X-axis as an example, let the position value sent from the previous interpolation cycle be x. i-1 The current interpolation period is x. i ;x i -xi-1 If the x-axis value is >0, the current movement is in the positive direction; otherwise, it is in the negative direction. i -x i-1 When the value is 0, the current state is stationary. The detection threshold for reversal can be set to 0.0001mm. When the position difference is less than 0.0001mm, it is not considered a reversal.

[0143] Since the processing and functions implemented by the device in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0144] The technical solution of this invention determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation of the backlash is performed according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0145] According to an embodiment of the present invention, a CNC system corresponding to the backlash compensation device is also provided. This CNC system may include the backlash compensation device described above.

[0146] Since the processing and functions implemented by the CNC system in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned device, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0147] The technical solution of this invention determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation of the backlash is performed according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0148] According to an embodiment of the present invention, a storage medium corresponding to the backlash compensation method is also provided, the storage medium including a stored program, wherein the program controls the device where the storage medium is located to execute the backlash compensation method described above when it is executed.

[0149] Since the processing and functions implemented by the storage medium in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0150] The technical solution of this invention determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation of the backlash is performed according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0151] According to an embodiment of the present invention, a computer program product corresponding to the backlash compensation method is also provided. The computer program product includes a computer program that, when processed and executed, implements the steps of the backlash compensation method described above.

[0152] Since the processing and functions implemented by the computer program product in this embodiment are basically corresponding to the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0153] The technical solution of this invention determines the target incremental compensation time for backlash incremental compensation based on the backlash jump value of the CNC machine tool's motion axis and a preset functional relationship model between the backlash jump value and the incremental compensation time. Based on the maximum backlash value, the target incremental compensation time, and a preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined. Within the target incremental compensation time, incremental compensation of the backlash is performed according to the compensation value. This not only offsets backlash errors in different scenarios but also controls the change rhythm through the target compensation time, reducing mechanical shock and vibration of the machine tool and improving operational stability and positioning accuracy.

[0154] In summary, it is readily understood by those skilled in the art that, without conflict, the aforementioned advantageous methods can be freely combined and superimposed.

[0155] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for compensating backlash, characterized in that, The method includes: Obtain the maximum backlash and reverse surge value of the motion axes of a CNC machine tool; Based on the reverse jump value and the preset functional relationship model between the reverse jump value and the incremental compensation time, the target incremental compensation time for performing reverse gap incremental compensation is determined. Based on the maximum backlash value, the target incremental compensation time, and the preset formula, the compensation value for backlash incremental compensation of the motion axis under different motion states is determined; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement; Within the target incremental compensation time, incremental compensation is performed on the backlash according to the compensation value.

2. The backlash compensation method according to claim 1, characterized in that, The preset functional relationship between the reverse jump value and the incremental compensation time is a first-order linear function model, expressed as: y=k·t c +b; Where y is the reverse impulse value, t c Let b be the incremental compensation time, b be a constant term, and k be a coefficient.

3. The backlash compensation method according to claim 1 or 2, characterized in that, When the motion state changes from rest to motion, the preset formula is: Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the start of the movement; when hour, or, When the motion state is from motion to rest, the preset formula is: Where Δc is the compensation value; k y k is the direction coefficient, which is the value when the motion axis is in the positive direction. y =1, when the motion axis is moving in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k t represents the current moment in the motion; e The moment when the motion stops; when hour, 4. The backlash compensation method according to claim 1 or 2, characterized in that, When the motion state is a change of direction during motion, the preset formula is: Where Δc is the compensation value; k y k is the direction coefficient before the changeover, when the motion axis before the changeover is in the positive direction. y =1, when the motion axis mentioned before the change is in the negative direction, k y =-1; L is the maximum value of the reverse clearance; t c The target incremental compensation time; t k The current moment after the reversal; t r This refers to the moment when the motion changes direction.

5. The backlash compensation method according to claim 3, characterized in that, The method further includes: When the motion state is from stationary to moving or from moving to stationary, the target total compensation value of the incremental compensation is half of the maximum value of the backlash; Once the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process stops and switches to stable compensation.

6. The backlash compensation method according to claim 4, characterized in that, The method further includes: When the motion state is a reversal during motion, the target total compensation value of the incremental compensation is the maximum value of the reverse clearance. Once the compensation value during the incremental compensation process reaches the target total compensation value, the incremental compensation process stops and switches to stable compensation.

7. A backlash compensation device, characterized in that, The device includes: The acquisition unit is configured to acquire the maximum backlash and the maximum backlash value of the CNC machine tool's motion axis; The calculation unit is configured to determine the target incremental compensation time for performing reverse gap incremental compensation based on the reverse jump value and a preset functional relationship model between the reverse jump value and the incremental compensation time. The calculation unit is further configured to determine the compensation value for backlash incremental compensation of the motion axis under different motion states based on the maximum backlash value, the target incremental compensation time, and a preset formula; the motion states include: from stationary to moving, from moving to stationary, and reversing during movement; The execution unit is configured to incrementally compensate the backlash according to the compensation value within the target incremental compensation time.

8. A numerical control system, characterized in that, include: The backlash compensation device as described in claim 7.

9. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the backlash compensation method as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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