Multi-axis synchronous start-stop control method for multi-axis high-speed chip mounter

Abstract

The invention discloses a multi-axis synchronous start-stop control method for a multi-axis high-speed chip mounter, which ensures the motion synchronization of a master axis and a slave axis in each stage according to the fact that the motion control of the master axis on the slave axis is more detailed, and ensures the motion synchronization of the master axis and the slave axis in each stage through the synchronous start-stop control on an X axis and a Y axis. According to the control method, vibration and positioning deviation caused by asynchronous movement between the shafts are reduced, the deceleration and the ending speed of the shafts are introduced, the applicability and the coupling of the control method are improved, and the control method has higher mounting precision under the higher mounting speed.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-axis synchronous start-stop motion control methods for multi-axis high-speed chip mounters, and in particular, to a multi-axis synchronous start-stop control method for multi-axis high-speed chip mounters. Background Art

[0002] In order to pursue faster and more stable chip mounting operations, during normal chip mounting operations, the movement control of the X-axis and Y-axis of a multi-axis high-speed chip mounter is precise, complex, and frequent. The electronic components are transported from the feeder position to above the substrate for chip mounting. The movement control of the X-axis and Y-axis during this process must be very precise to ensure the accurate positioning of the chip head, and at the same time, the body vibration caused by multi-axis movement should be reduced as much as possible.

[0003] In the Chinese invention patent with the publication number CN118519393A, it is mentioned that the X-axis and Y-axis are controlled for synchronous start-stop. By comparing the movement step lengths of each movement, the master axis and slave axes are distinguished, and then the movement parameters of the slave axes are re-planned according to the movement parameters of the master axis to achieve the effect of multi-axis synchronous start-stop. However, no segmentation processing is performed, but the control plan is based on the time of the complete movement, and it cannot ensure that the slave axes change in real time following the change of the movement state of the master axis. Therefore, the vibration and the influence on accuracy caused by the asynchronous acceleration and deceleration movement states still cannot be avoided, and it defaults that the acceleration and deceleration are the same during each movement process and the end speed is 0, so the applicable range is too single. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a multi-axis synchronous start-stop control method for multi-axis high-speed chip mounters, which ensures the movement synchronization of the master and slave axes in each stage, thereby reducing the vibration and positioning deviation caused by the asynchronous movement between the axes, and having higher chip mounting accuracy at the same ratio under a faster chip mounting speed.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is: a multi-axis synchronous start-stop control method for multi-axis high-speed chip mounters, which is characterized by including the following steps:

[0006] Step 1: Obtain the movement parameters when the axes of the multi-axis high-speed chip mounter need to move synchronously. The multi-axis synchronous start-stop control of the multi-axis high-speed chip mounter only performs movement control on its X-axis and Y-axis. The movement parameters include start speed, target speed, end speed, acceleration time, deceleration time, and target position. The master axis and slave axes are determined by comparing the magnitudes of the step lengths of the X-axis and Y-axis moving to the target positions respectively. The axis with the longest distance is determined as the master axis, and the other axes are determined as slave axes;

[0007] Step 2: Determine the uniform motion time T of the main shaft according to the time duration of each stage of the slave shaft to keep in sync with the main shaft. u-m Equal to the uniform motion time T of the slave shaft u-s , where T u-m The calculation method is as follows:

[0008] From S u-m = T u-m V max-m Determine.

[0009]

[0010] Step 3: Determine the relationship between the uniform step length of the main shaft and other motion parameters. The step length of each stage of the main shaft is equal to the total step length afterwards. The uniform step length of the main shaft is obtained by subtracting the acceleration section step length S a And the deceleration section step length S d . The calculation formula is

[0011] S u-m = S m - S a-m - S d-m ;

[0012] According to the initial parameters of the main shaft obtained, the acceleration A m And the deceleration D m Of the main shaft are obtained. The calculation formula is

[0013]

[0014] Based on the calculated acceleration and deceleration of the main shaft, the acceleration section step length S a-m And the deceleration section step length S d-m Of the main shaft are further obtained. The calculation formula is

[0015]

[0016] Substitute into the above formula to obtain the uniform step length of the main shaft:

[0017]

[0018] Where S m Is the target position of the main shaft;

[0019] Step 4: Determine the relationship between the uniform step length of the slave shaft and other motion parameters. Since the slave shaft needs to follow the main shaft to start and stop in sync, the motion time of each stage of the slave shaft is the same as that of the main shaft. That is, the acceleration time, uniform motion time, and deceleration time of the slave shaft are T a-m , T u-m , T d-m, based on this, re-plan the target speed, acceleration, and deceleration of the slave axis. Assume the new target speed of the slave axis is V max-s1 , the acceleration is A s1 and the deceleration is D s1 , from S u-s = T u-m V max-s1 is determined

[0020]

[0021] According to the relationship between the target speed and the acceleration and deceleration, we can get:

[0022]

[0023] Subtracting the above two equations and transposing terms, we get the relationship between the deceleration and the acceleration:

[0024]

[0025] Furthermore, we get the acceleration section step size S of the slave axis a-s and the deceleration section step size S d-s , and the calculation formula is

[0026]

[0027] Substituting the above formula, we get the constant speed step size of the slave axis:

[0028]

[0029] where S s is the target position of the slave axis;

[0030] Step 5: Substitute the constant speed step sizes of the master and slave axes into the constant speed time equation. The calculation formula is

[0031]

[0032] Step 6: Combining the above derivation results, we get:

[0033]

[0034] After replacing V max-s1 and D s1 , we get an equation with only one unknown, the acceleration A of the slave axis s1 , and the calculation formula is

[0035]

[0036] After simplifying, combining like terms, and transposing, we can obtain the expression of the acceleration A of the slave axis s1 as:

[0037]

[0038] Obtain the planned acceleration A of the slave axis s1 After that, the planned target speed and deceleration of the slave axis are obtained, so as to truly realize the synchronous start-stop control between multiple axes.

[0039] The advantages of the present invention compared with the prior art are as follows: The movement control of the slave axis by the main axis in the present invention is more detailed, ensuring the movement synchronization of the main and slave axes in each stage. The synchronous start control of the XY axes ensures the movement synchronization of the main and slave axes in each stage, thereby reducing the vibration and positioning deviation caused by the asynchronous movement between the axes, and introducing the deceleration and end speed of the axis, improving the applicability and coupling of the control method, and having higher mounting accuracy at the same ratio under a faster mounting speed. Description of the Drawings

[0040] Figure 1 It is a trajectory comparison diagram before and after the multi-axis synchronous start planning of the present invention. Detailed Embodiments

[0041] Figure 1 As shown, taking the T-shaped acceleration and deceleration curve as an example: When multiple axes start moving simultaneously, if no control intervention is applied, both the main axis and the slave axis will move along the movement trajectory presented by the solid line in the figure, that is, the main axis will move with acceleration A m and deceleration D m The slave axis will move with acceleration A s and deceleration D s Obviously, the movement between the axes is not synchronous, which will lead to a decrease in positioning accuracy and an increase in machine body vibration, affecting the accuracy and reliability of the overall mounting.

[0042] The present invention proposes a multi-axis synchronous start-stop control method for a multi-axis high-speed mounter. The core idea is to ensure that the slave axis can change following the change of the movement state of the main axis, that is, to ensure that the time duration of each stage of the slave axis is synchronized with the main axis. As shown by the dotted line of the slave axis in the figure, the slave axis moves with the newly planned acceleration A s1 and deceleration D s1 and can be synchronized with the main axis in each stage, thus eliminating the above-mentioned problems.

[0043] A multi-axis synchronous start-stop control method for a multi-axis high-speed mounter Figure 1 As shown, it includes the following steps

[0044] Step 1: Obtain the motion parameters when the multi-axis high-speed mounter needs to move synchronously. The multi-axis synchronous start / stop control of the multi-axis high-speed mounter specifically performs motion control only on its X-axis (X-axis motor shaft) and Y-axis (Y-axis motor shaft). The motion parameters include start speed, target speed, end speed, acceleration time, deceleration time, and target position. The main axis and slave axes are determined by comparing the step sizes of the X-axis and Y-axis moving to the target positions respectively. The axis with the longest distance is determined as the main axis, and the other axes are determined as slave axes.

[0045] Step 2: Determine the uniform motion time T of the main axis according to the time durations of each stage of the slave axis to be synchronized with the main axis. u-m Equal to the uniform motion time T of the slave axis u-s , where T u-m The calculation method is as follows:

[0046] From S u-m = T u-m V max-m Determine.

[0047]

[0048] Step 3: Determine the relationship between the uniform step size of the main axis and other motion parameters. The step size of each stage of the main axis is equal to the total step size later. The uniform step size of the main axis is obtained as the total step size minus the acceleration section step size S a and the deceleration section step size S d . The calculation formula is

[0049] S u-m = S m - S a-m - S d-m .

[0050] According to the initial parameters of the main axis obtained, the acceleration A m and deceleration D m of the main axis are obtained. The calculation formula is

[0051]

[0052] Based on the calculated acceleration and deceleration of the main axis, the acceleration section step size S a-m and deceleration section step size S d-m of the main axis are further obtained. The calculation formula is

[0053]

[0054] Substitute into the above formula to obtain the uniform step size of the main axis:

[0055]

[0056] where S mThe target position of the main shaft.

[0057] Step 4: Determine the relationship between the constant velocity step length of the slave axis and other motion parameters. Since the slave axis needs to start and stop synchronously with the main axis, the motion time of each stage of the slave axis is the same as that of the main axis, that is, the acceleration time, constant velocity time, and deceleration time of the slave axis are T a-m , T u-m , T d-m respectively. Based on this, re-plan the target velocity, acceleration, and deceleration of the slave axis. Assume the new target velocity of the slave axis is V max-s1 , the acceleration is A s1 and the deceleration is D s1 . From S u-s = T u-m V max-s1 it is determined.

[0058]

[0059] According to the relationship between the target velocity and the acceleration and deceleration, we can get:

[0060]

[0061] Subtract the above two equations and transpose to get the relationship between the deceleration and the acceleration:

[0062]

[0063] Further obtain the acceleration section step length S a-s and the deceleration section step length S d-s . The calculation formula is

[0064]

[0065] Substitute into the above formula to get the constant velocity step length of the slave axis:

[0066]

[0067] where S s is the target position of the slave axis.

[0068] Step 6: Substitute the constant velocity step lengths of the master and slave axes into the constant velocity time equation. The calculation formula is

[0069]

[0070] Step 6: Combine the above derivation results to obtain:

[0071]

[0072] After replacing V max-s1 and D s1 , we get only the acceleration A of the slave axiss1 An equation with one unknown, the calculation formula is

[0073]

[0074] After simplifying, combining like terms and transposing terms, the acceleration A of the slave axis can be obtained s1 The expression is:

[0075]

[0076] The planned acceleration A of the slave axis is obtained s1 After that, the planned target speed and deceleration of the slave axis are obtained, so as to truly realize the synchronous start-stop control between multiple axes.

[0077] The present invention will be further described below in conjunction with specific instantiated data parameters. It should be noted that in order to ensure a clear example, all the following calculation results are reserved as integers.

[0078] Suppose that in a normal placement operation of the placement machine described in the present invention, the preset motion parameters of the X and Y axes are as shown in the following table:

[0079] Table 1 Preset motion parameters

[0080]

[0081] Combined with the parameters in the above table, first judge the motion step lengths of the X and Y axes, and it can be clearly obtained that the Y axis is the main axis and the X axis is the slave axis.

[0082] Then the acceleration of the main axis is obtained as 16663333 pulse / s 2 , and the deceleration is 12497500 pulse / s 2 .

[0083] Substitute the acceleration and deceleration of the main axis into the expression of the acceleration of the slave axis, and the planned acceleration of the slave axis can be obtained as 8801048 pulse / s 2 , and then the target speed of the slave axis is obtained as 264131 pulse / s, and the deceleration is 6600775 pulse / s 2 . At this point, when the slave axis runs with the above planned parameters, it can ensure that the slave axis changes in real time strictly following the change of the motion state of the main axis.

[0084] Compared with the technology and the technical solution proposed in the Chinese invention patent with the patent publication number CN118519393A, the motion control of the slave axis by the main axis in the present invention is more detailed, ensuring the motion synchronization of the main and slave axes in each stage. The synchronous start control of the XY axes ensures the motion synchronization of the main and slave axes in each stage, and has the following advantages:

[0085] (1) Through the control algorithm of synchronous start and stop, the movements of the X-axis and Y-axis can be precisely coordinated, reducing vibrations and positioning deviations caused by asynchronous movements between the axes, and significantly improving the placement accuracy.

[0086] (2) Effectively alleviate the excessive impact or wear on the mechanical components of the mounter caused by asynchronous movements of the X-axis and Y-axis, thereby shortening the service life of the equipment or causing equipment failures.

[0087] (3) Contribute to improving the overall performance and stability of the mounter, and reducing the failure rate caused by vibrations and positioning deviations.

Claims

1. A multi-axis synchronous start-stop control method for a multi-axis high-speed placement machine, characterized in that: The following steps are involved: Step 1: Obtain the motion parameters of each axis of the multi-axis high-speed placement machine when it needs to move synchronously. The multi-axis synchronous start-stop control of the multi-axis high-speed placement machine is to control the motion of only its X-axis and Y-axis. The motion parameters include starting speed, target speed, ending speed, acceleration time, deceleration time and target position. The master axis and slave axis are determined by comparing the step sizes of the X-axis and Y-axis moving to the target position respectively. The axis with the longest distance is determined as the master axis, and the other axes are determined as slave axes. Step 2: According to the duration of each stage of the slave axis to keep synchronization with the master axis, determine the uniform motion time T of the master axis u-m Equal to the time T of uniform motion from the axis u-s , where T u-m The calculation is as follows: By S u-m =T u-m V max-m Sure, Step 3: Determine the relationship between the uniform speed step length of the main axis and other motion parameters. The step length of each stage of the main axis is equal to the total step length. The uniform speed step length of the main axis is the total step length minus the acceleration step length S. a and deceleration step length S d , the calculation formula is, S u-m =S m -S a-m -S d-m ; According to the initial parameters of the spindle obtained, the acceleration A of the spindle is obtained m and deceleration D m , the calculation formula is, Based on the calculated spindle acceleration and deceleration, the spindle acceleration step length S is further obtained. a-m and deceleration step length S d-m , the calculation formula is, Substituting into the above formula, we can get the uniform speed step length of the main axis: Where S m is the target position of the main axis; Step 4: Determine the relationship between the uniform speed step length of the slave axis and other motion parameters. Since the slave axis needs to start and stop synchronously with the master axis, the motion time of each stage of the slave axis is consistent with that of the master axis, that is, the acceleration time, uniform speed time and deceleration time of the slave axis are T and T respectively. a-m , T u-m , T d-m Based on this, re-plan the target speed, acceleration and deceleration of the slave axis. Assume that the new target speed of the slave axis is V max-s1 , acceleration is A s1 and the deceleration is D s1 , by S u-s =T u-m V max-s1 Sure, According to the relationship between the target speed and the acceleration and deceleration, we can get: Subtracting the above two equations and shifting the terms, we can get the relationship between deceleration and acceleration: Further obtain the acceleration step length S of the slave axis a-s and deceleration step length S d-s , the calculation formula is, Substituting the above formula, we can get the uniform speed step length of the slave axis: Where S s is the target position of the slave axis; Step 5: Substitute the uniform speed step of the master and slave axes into the uniform speed time equation. The calculation formula is: Step 6: Combine the above derivation results to get: Replace V max-s1 and D s1 After that, we get only the acceleration A of the slave axis s1 The calculation formula for this unknown quantity is, After simplifying and combining similar terms and moving the terms, we can get the acceleration A of the slave axis. s1 The expression is: Get the planned slave axis acceleration A s1 After that, the planned slave axis target speed and deceleration are obtained, thus realizing the synchronous start and stop control among multiple axes in a true sense.

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