Method, device and equipment for planning S-shaped motion track with asymmetric acceleration in chip mounting and medium

Abstract

The invention discloses an S-shaped motion track planning method and device with asymmetric acceleration in chip mounting, equipment and a medium, an S-shaped track curve is divided into seven sections, the time of the seven sections of tracks is independently calculated according to limiting conditions, and the track curve of each time period is solved through an integration method; the smoothness and accuracy of the motion trail in the acceleration and deceleration process are further optimized by using asymmetric control of the acceleration, and the problems of vibration and position overshoot caused by excessive compression of the acceleration time are relieved, so that the overshoot phenomenon is more effectively inhibited, the impact force of the mounting head is reduced, and the integrity of materials is protected.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing technology, and in particular relates to a method, apparatus, equipment and medium for planning S-shaped motion trajectories with asymmetric acceleration in chip mounting. Background Technology

[0002] During the operation of a high-speed pick-and-place machine, the placement head moves rapidly along the Z-axis to place components. With the continuous improvement of the performance and operating speed of high-speed pick-and-place machines, Z-axis position control has become particularly critical. Under high-speed and high-acceleration conditions, overshoot or vibration may occur in the Z-axis position, which can not only affect placement accuracy but also potentially damage the placement head or components, leading to increased scrap rates and maintenance costs. Therefore, effectively controlling the Z-axis movement trajectory to reduce overshoot and improve placement accuracy is a key technical challenge in the design and control of high-speed pick-and-place machines.

[0003] Most current trajectory planning methods employ asymmetric S-curve planning algorithms. For example, patent CN112327954B discloses a high-precision positioning method for linear motors using asymmetric S-curve speed curve control. This method introduces different accelerations and decelerations during the rising and falling phases of the speed curve to mitigate the impact of acceleration and deceleration in high-speed pick-and-place machines. However, the asymmetric S-curve speed trajectory requires the motor to have higher dynamic response and peak power output. Furthermore, excessive compression of acceleration time can easily cause vibration and reduce the stability of the control system.

[0004] Therefore, it is necessary to provide a new method for planning S-shaped motion trajectories with asymmetric acceleration in chip mounting to solve the above-mentioned technical problems. Summary of the Invention

[0005] One of the main objectives of this invention is to provide a method for planning an S-shaped motion trajectory with asymmetric acceleration in chip mounting, which can effectively suppress overshoot, reduce the impact force of the mounting head, and protect the integrity of the material.

[0006] This invention achieves the above objective through the following technical solution: a method for planning S-shaped motion trajectories with asymmetric acceleration in chip mounting, comprising the following steps: Step 1: Referring to the motor performance parameters, set the limiting conditions for the trajectory curve under the motor performance limits. The limiting conditions include the maximum speed limit v. max Maximum acceleration limit a amax Maximum deceleration limit a dmax The maximum jerk J during the acceleration phase a,amax and maximum acceleration / deceleration J a,dmax The maximum acceleration J during the deceleration phase d,amax Maximum acceleration / deceleration J d,dmax ; Step 2: Divide the trajectory curve into seven segments, and set the time periods for the seven segments as follows: (1) Acceleration period: including the first acceleration rise period T1, the first acceleration hold period T2 and the first acceleration fall period T3; (2) The uniform speed time period T4; (3) Deceleration time period: including the second acceleration rise time period T5, the second acceleration hold time period T6 and the second acceleration fall time period T7; Step 3: Set the time period calculation formulas for the seven trajectory segments as follows: ; ; ; ; ; ; ,in, To accelerate the displacement over a period of time, S represents the displacement during the deceleration period, and S is the total displacement, where S = q1 - q0, q0 is the initial position, and q1 is the final position. ; ; Step 4: Update the time calculation formula for the time periods of the seven trajectory segments according to the parameter constraints, which includes: (1) If T2=0, then the a in the time period calculation formula of the seven trajectories in step 3 is used. amax Using the actual maximum acceleration a reala Replace, then update T1~T7; (2) If T6=0, then the a in the time period calculation formula of the seven trajectories in step 3 is changed. dmax Using the actual maximum deceleration a reald Replace, then update T1~T7; (3) If T4=0, then the v in the time period calculation formula of the seven trajectories mentioned in step 3 will be changed. max Using the actual maximum speed v real Replace, then update T1~T7; (4) If T2=0 and T6=0, then the a in the time period calculation formula of the seven trajectories mentioned in step 3 is changed. amax Using the actual maximum acceleration a reala Replace, use a dmax Using the actual maximum deceleration a reald Replace, then update T1~T7; (5) If T2=0 and T4=0, then the a in the time period calculation formula of the seven trajectories mentioned in step 3 is changed to amax Using the actual maximum acceleration a reala Replace, will v max Using the actual maximum speed v real Replace, then update T1~T7; (6) If T4=0 and T6=0, then the v in the time period calculation formula of the seven trajectories mentioned in step 3 is changed. max Using the actual maximum speed v real Replace, use a dmax Using the actual maximum deceleration a reald Replace, then update T1~T7; (7) If T2=0, T4=0, and T6=0, then the a in the time period calculation formula of the seven trajectories mentioned in step 3 is changed to 0. amax Using the actual maximum acceleration a reala Replace, use a dmax Using the actual maximum deceleration a reald Replace, then update T1~T7; Step 5: Based on the times of the seven trajectory segments obtained in Steps 3 and 4, obtain the acceleration of the S-shaped trajectory curve with asymmetric acceleration. ,speed Displacement The expressions are as follows: ; ; ; Formula (11) is: ; Formula (12) is: ; Formula (13) is: ; Formula (14) is: ; Formula (15) is: .

[0007] Furthermore, in the aforementioned constraints, each parameter satisfies J. a,amax >J a,dmax J d,amax >J d,dmax a amax >a dmax .

[0008] Furthermore, the actual maximum acceleration a reala The calculation method is as follows: The actual maximum acceleration comes from 0~a amax Let the left boundary be a. aleft =0, a aright =a amax ; to the new maximum acceleration The limit is half of the original, that is... , replacing a amax Calculate T2 according to the formula in step 3; if T2 > 0, then let a aleft = a aright =a aright If T2 < 0, then let a aleft =a aleft a aright = Then, the new maximum acceleration is calculated for the next round and the process is repeated iteratively. When T2=0, the iteration ends, and the final maximum acceleration is obtained. ,make .

[0009] Furthermore, the actual maximum deceleration a reald The calculation method is as follows: The actual maximum deceleration comes from 0 to a dmax Let the left boundary be a. dleft =0, a dright =a dmax ; to make the new maximum deceleration The limit is half of the original, that is... , replacing a dmax Calculate T6 according to the formula in step 3; if T6 > 0, then let a dleft = a dright =a dright If T6 < 0, then let a dleft =a dleft a dright = Then, the new maximum deceleration is calculated for the next round and the process is repeated iteratively. When T6 = 0, the iteration ends, and the final maximum deceleration is obtained. ,make .

[0010] Furthermore, the actual maximum speed v real The calculation method is as follows: The actual maximum speed comes from 0~v max Let the left boundary be v. left =0, v right =vmax ; to achieve a new maximum speed The limit is half of the original, that is... , replacing v max Calculate T4 according to the formula in step 3; if T4 > 0, then let v left = v right =v right If T4 < 0, then let v left =v left v right = Then, the new maximum speed is calculated for the next round and the iteration is repeated. When T4=0, the iteration ends and the final maximum speed is obtained. ,make .

[0011] Another object of the present invention is to provide a planning device for an acceleration-asymmetric S-shaped trajectory curve, comprising: The first judgment module determines whether the acceleration can reach the maximum acceleration during the motion process; The second judgment module determines whether the deceleration can reach the maximum deceleration during the motion process; The third judgment module determines whether the speed can reach the maximum speed during the movement; The first calculation module includes a first relation, a second relation, and a third relation. The first relation is used to calculate the maximum acceleration a. amax With the maximum jerk j during the acceleration phase a,amax The acceleration rise time T1 during the acceleration phase is calculated; the second relationship is used to calculate the maximum acceleration a. amax With the maximum acceleration / deceleration j during the acceleration phase a,dmax The acceleration descent time T3 during the acceleration phase is calculated; the third relation is used to calculate the acceleration descent time T3 based on T1, T3, and the maximum velocity v. max j a,amax The acceleration hold time T2 during the acceleration phase is calculated; the first relationship is: The second relation is The third relation is: ; The second calculation module includes a fourth relation, a fifth relation, and a sixth relation. The fourth relation is used to calculate the maximum deceleration a. dmax With the maximum acceleration j during the deceleration phase d,amax The acceleration rise time T5 during the deceleration phase is calculated; the fifth relation is used to calculate the maximum acceleration a. dmax With the maximum acceleration / deceleration j during the deceleration phase d,dmaxThe acceleration descent time T7 during the deceleration phase is calculated; the sixth relation is used to calculate the acceleration descent time T7 based on T5, T7, and the maximum speed v. max j d,amax The acceleration hold time T6 during the deceleration phase is calculated; the fourth relation is... The fifth relation is: The sixth relation is: ; The third calculation module includes a seventh relation, which is used to calculate the maximum jerk j during the acceleration phase. a,amax Maximum acceleration / deceleration j a,dmax The displacement during the acceleration phase is calculated using T1, T2, and T3. According to the maximum acceleration j during the deceleration phase d,amax Maximum acceleration / deceleration j d,dmax The displacement during the deceleration phase is calculated using T5, T6, and T7. According to the total displacement S, , and maximum speed v max The time T4 of the uniform velocity phase is calculated; the seventh relation is: ; ; ; The planning module includes the eighth, ninth, and tenth relations. The eighth relation is used to plan the acceleration of an asymmetric S-shaped trajectory curve. The ninth relation is used to plan the velocity of the S-shaped trajectory curve with asymmetric acceleration. The tenth relation is used to plan the displacement of the S-shaped trajectory curve with asymmetric acceleration. .

[0012] Furthermore, the eighth relation is: .

[0013] Furthermore, the ninth relation is: .

[0014] Furthermore, the tenth relation is obtained by integrating the ninth formula, and is as follows: ; Formula (11) is: ; Formula (12) is: ; Formula (13) is: ; Formula (14) is: ; Formula (15) is: .

[0015] Furthermore, it also includes: The first solution module uses the bisection method to solve the problem from 0 to the maximum acceleration a. amax Between, the maximum acceleration a in the first calculation module amax Perform iterative iterations until T2=0, at which point the iteration ends and the actual maximum acceleration a is obtained. reala ; The second solution module uses the bisection method to calculate the range from 0 to the maximum deceleration a. dmax Between, the maximum deceleration a in the second calculation module dmax Perform iterative iterations until T6=0, at which point the iteration ends and the actual maximum deceleration a is obtained. reald ; The third solution module uses the bisection method to solve the problem from 0 to the maximum velocity v. max Between these three calculation modules, the maximum speed v is measured at the highest speed v in the first, second, and third calculation modules. max Perform iterative iterations until T4=0, at which point the iteration ends and the actual maximum speed v is obtained. real .

[0016] Another object of the present invention is to provide a planning device for an acceleration asymmetric S-shaped trajectory curve, comprising: a memory for storing a computer program; and a processor for executing the steps of the computer program as follows: S1. The first judgment module determines whether the maximum acceleration can be reached based on the input motion parameters. If it can, T1 and T3 are calculated by the first calculation module, and then step S2 is executed. Otherwise, T2 is set to zero, and the actual maximum acceleration is solved by the first solution module. The actual maximum acceleration is then input into the first calculation module as the maximum acceleration to calculate T1 and T3, and then step S2 is executed. S2. The second judgment module determines whether the maximum deceleration can be reached based on the input motion parameters. If it can, T5 and T7 are calculated by the second calculation module, and then step S3 is executed. Otherwise, T6 is set to zero, and the actual maximum deceleration is solved by the second solution module. The actual maximum deceleration is then input into the second calculation module as the maximum deceleration to calculate T5 and T7, and then step S3 is executed. S3. The third judgment module determines whether the maximum speed can be reached based on the input motion parameters. If it can, T2 and T6 are calculated by the first calculation module and the second calculation module respectively, and then step S4 is executed. Otherwise, T4 is set to zero, and the actual maximum speed is solved by the third solution module. The actual maximum speed is then used as the maximum speed and input into the first calculation module and the second calculation module to calculate T2 and T6 respectively, and then step S5 is executed. S4, the third calculation module calculates T4; S5. The planning module plans the acceleration asymmetric S-shaped trajectory curve based on T1, T2, T3, T4, T5, T6, and T7 calculated in steps S1 to S4.

[0017] Another object of the present invention is to provide a computer-readable storage medium on which a computer program is stored, the computer program being executed by a processor using the method steps described above.

[0018] Compared with the prior art, the beneficial effects of the present invention regarding the planning method, apparatus, equipment, and medium for S-shaped motion trajectory with asymmetric acceleration in chip mounting are as follows: (1) Divide the S-shaped trajectory curve into seven segments, calculate the time of the seven segments independently according to the constraints, and solve the trajectory curve of each time segment by integral method; use the asymmetric control of acceleration to further optimize the smoothness and accuracy of the motion trajectory during acceleration and deceleration, alleviate the vibration and position overshoot caused by excessive compression of acceleration time, thereby more effectively suppressing the overshoot phenomenon, reducing the impact force of the mounting head, and protecting the integrity of the material. (2) The algorithm causes the placement head to gradually decelerate as it approaches the target position, effectively preventing material damage and ensuring placement accuracy and quality; (3) It not only improves the operational reliability of the pick and place machine, but also significantly improves production efficiency, providing more stable technical support for high-speed placement processes; (4) This method can more flexibly adjust the trend of acceleration increase or decrease during acceleration and deceleration, realize the adjustment of the speed of acceleration rise and fall as needed, and make the speed trajectory smoother during acceleration and deceleration, so as to optimize the movement trajectory of the high-speed pick and place machine in the Z-axis direction and prevent the placement head from damaging the material due to overshoot. (5) In addition, since the trajectory design is more in line with the dynamic response characteristics of the Z-axis, the algorithm ensures a smooth transition during acceleration and deceleration, reduces the peak current and load impact of the motor, and can significantly reduce mechanical vibration and power consumption, thereby extending the service life of the motor and equipment and reducing maintenance costs. These optimization effects can comprehensively improve the reliability and accuracy of the chip mounter, bringing significant production efficiency and cost savings to enterprises. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall process of an embodiment of the present invention; Figure 2 This is a schematic diagram of the trajectory of an asymmetric S-velocity curve. Figure 3a This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T2=0 in an embodiment of the present invention; Figure 3b This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T6=0 in an embodiment of the present invention; Figure 3c This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T4=0 in an embodiment of the present invention; Figure 4a This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T2=0 and T6=0 in an embodiment of the present invention; Figure 4b This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T2=0 and T4=0 in an embodiment of the present invention; Figure 4c This is a schematic diagram of the asymmetric S-shaped trajectory curve of acceleration when T4=0 and T6=0 in an embodiment of the present invention; Figure 5 This is a schematic diagram of the asymmetric S-shaped trajectory curves of acceleration when T2=0, T4=0, and T6=0 in an embodiment of the present invention; Figure 6 This is a schematic diagram of an S-shaped trajectory curve with asymmetric acceleration planned under set parameters in an embodiment of the present invention; Figure 7 This is a schematic diagram of an asymmetric S-shaped velocity trajectory planned under set parameters in an embodiment of the present invention; Figure 8 This is a schematic diagram of the framework principle structure of the planning device in an embodiment of the present invention; Figure 9 This is a schematic diagram of the planning device in an embodiment of the present invention; The numbers in the diagram represent: A planning device for an asymmetric S-shaped trajectory curve with 100-acceleration; 1-First judgment module; 2-Second judgment module; 3-Third judgment module; 4-First calculation module; 5-Second calculation module; 6-Third calculation module; 7-First solution module; 8-Second solution module; 9-Third solution module; 10-Planning module. Detailed Implementation

[0020] Example 1: Please refer to Figure 1This embodiment describes a method for planning an S-shaped motion trajectory with asymmetric acceleration in chip mounting, which includes the following steps: Step 1: Determine the constraints for planning the S-shaped trajectory curve with asymmetric acceleration (hereinafter referred to as "trajectory curve").

[0021] Based on the motor's performance parameters, determine the maximum speed and maximum acceleration the motor can withstand. The maximum operating speed of the motor is usually given in the motor parameter table, while the maximum acceleration is calculated as follows: F max is the maximum thrust of the motor, and m is the motor load.

[0022] Determine the constraints required for trajectory planning under the constraints of the maximum speed and maximum acceleration that the motor can withstand, including: (1) Constraint 1: Four jerk constraints: the maximum jerk j during the acceleration phase a,amax and maximum acceleration / deceleration j a,dmax The maximum acceleration j during the deceleration phase d,amax and maximum acceleration / deceleration j d,dmax ; (2) Restriction condition two: two acceleration restrictions: maximum acceleration a amax Maximum deceleration a dmax ; (3) Restriction condition three: maximum speed v max limit.

[0023] These three constraints ensure that the trajectory conforms to the physical performance of the motor, thus avoiding performance degradation or equipment damage caused by overload.

[0024] In the application of the asymmetric S-shaped motion trajectory, based on the motion characteristics of the mounting Z-axis, the deceleration time is set to be longer than the acceleration time, and the acceleration descent time is set to be longer than the acceleration ascent time. Specifically, this is reflected in the selection of limiting parameters, where J... a,amax >J a,dmax J d,amax >J d,dmax a amax >a dmax .

[0025] Step 2: Set the calculation formula for the running time of each segment of the trajectory according to the above constraints.

[0026] The placement head moves point-to-point along the Z-axis, with the initial position set to q0 and the final position to q1. (See reference below.) Figure 2The trajectory curve shown is divided into three stages: acceleration, constant velocity, and deceleration. The acceleration and deceleration stages are further divided into acceleration increase stage, acceleration maintenance stage, and acceleration decrease stage, forming a total of seven trajectory segments. The time of the seven trajectory segments is then divided as follows: (1) Acceleration period: including the first acceleration rise period T1, the first acceleration hold period T2 and the first acceleration fall period T3; (2) The uniform speed time period T4; (3) Deceleration period: including the second acceleration rise period T5, the second acceleration hold period T6 and the second acceleration fall period T7.

[0027] The trajectory accelerates from 0 to its maximum acceleration a during time interval T1. amax T1 is subjected to the maximum acceleration a during operation amax Therefore, due to limitations: Formula (1)

[0028] The trajectory reaches its maximum speed v at the end of time period T3. max During this time period, the acceleration decreases from maximum to 0, therefore: Formula (2)

[0029] Since T1 and T3 are both related to a amax Related, therefore And because Therefore: Formula (3)

[0030] Similarly, the trajectory reaches its maximum deceleration 'a' from 0 during time interval T5. dmax T5 is subject to the maximum deceleration a during operation dmax Therefore, due to limitations: Formula (4)

[0031] Similarly, the trajectory changes from maximum deceleration a during time interval T7. dmax The speed increases to 0, therefore: Formula (5)

[0032] Since T5 and T7 are both related to a dmax Related, therefore And because Therefore: Formula (6)

[0033] In this embodiment, the calculation of the uniform motion time T4 takes into account the total displacement S, where S = q1 - q0, and the uniform motion time period is: Formula (7)

[0034] in, To accelerate the displacement over a period of time, The displacement is the time interval of deceleration; and: ; .

[0035] During the acceleration phase, this embodiment uses different calculation formulas for T1 and T3 to make the acceleration during the acceleration rise and acceleration fall periods different, thus forming asymmetric acceleration control. Similarly, during the deceleration phase, different calculation formulas for T5 and T7 make the acceleration during the deceleration rise and acceleration fall periods different, thus forming asymmetric acceleration control. This makes the motion trajectory smoother and more precise during acceleration and deceleration, effectively mitigating the vibration and position overshoot problems caused by excessive compression of acceleration time.

[0036] Step 3: Time allocation and update of the parameter-constrained, asymmetric S-shaped trajectory curve of acceleration.

[0037] It is worth noting that the trajectory described in step 2 is a complete seven-segment trajectory. Due to the constraints, the maximum speed v in the constraints may appear. max Maximum acceleration a amax Maximum deceleration a dmax If certain parameters are not met, i.e., one, two, or three of the following time periods—the first acceleration holding time period T2, the second acceleration holding time period T6, and the constant velocity time period T4—are missing, then some of the seven time periods need to be recalculated. Specifically, this includes: (1) Case (I): Maximum acceleration a amax If unreachable, it means there is no uniform acceleration component during the acceleration phase, i.e., T2=0. In this case, T1 and T3 are limited by the actual maximum acceleration a of the trajectory. reala Using the actual maximum acceleration a reala Replace a amax The calculations for time periods T1 and T3 are updated as follows: .

[0038] Because T1, T2, and T3 have changed, T4 has also changed, while the specific values ​​of T5 to T7 remain unchanged. However, the start and end times of the corresponding trajectories have changed.

[0039] This embodiment designs an effective calculation method for T1 and T3, namely, using a bisection method for iterative calculation to determine the actual maximum acceleration a. reala , improve a reala The retrieval speed is determined by the retrieval termination condition T2=0, and then the actual maximum acceleration a is used. reala Replace 'a' in formulas (1), (2), and (3) amax Calculations are performed to update T1 and T3. Specifically, this includes: The actual maximum acceleration comes from 0~a amax Left boundary a aleft =0, a aright =a amax ; to the new maximum acceleration The limit is half of the original, that is... , replacing a amax Substitute these values ​​into formulas (1), (2), and (3) to calculate T2; if T2 > 0, then let a aleft = a aright =a aright If T2 < 0, then let a aleft =a aleft a aright = Then, the new maximum acceleration is calculated for the next round and the process is repeated iteratively. When T2=0, the iteration ends, and the final maximum acceleration is obtained. ,make .

[0040] (2) Case (II): Maximum deceleration a dmax If unreachable, it means there is no uniform deceleration during the deceleration phase, i.e., T6=0. In this case, T5 and T7 are limited by the actual maximum deceleration a of the trajectory. reald Using the actual maximum deceleration a reald Replace a dmax The calculations for time periods T5 and T7 have been updated as follows: .

[0041] Because T5 and T7 have changed, T4 has also changed, but the values ​​of T1 to T3, as well as the start and end times of the corresponding trajectories, remain unchanged.

[0042] This embodiment designs an effective calculation method for T5 and T7, namely, using a bisection method for iterative calculation to determine the actual maximum deceleration a. reald , improve a reald The retrieval speed is determined by the retrieval termination condition T6=0, and then the actual maximum deceleration a is used. realdReplace 'a' in formulas (4), (5), and (6) dmax Calculations are performed to update T5 and T7. Specifically, this includes: The actual maximum deceleration comes from 0 to a dmax Left boundary a dleft =0, a dright =a dmax Let the new maximum deceleration The limit is half of the original, that is... , replacing a dmax Substituting into formulas (4), (5), and (6), we can calculate T6; if T6 > 0, then let a dleft = a dright =a dright If T6 < 0, then let a dleft =a dleft a dright = Then, the new maximum deceleration is calculated for the next round and the process is repeated iteratively. When T6 = 0, the iteration ends, and the final maximum deceleration is obtained. ,make .

[0043] (3) Case (three): Maximum speed v max If unreachable, it means there is no uniform velocity phase, and T4 = 0. In this case, the calculation of T2 and T6 is limited by the actual maximum speed v of the trajectory. real Using the actual maximum speed v real Replace v max The calculations for time periods T2 and T6 are updated as follows: .

[0044] This embodiment designs an effective calculation method for T2 and T6, namely, using a bisection method for iterative calculation to determine the actual maximum speed v. real , improve v real Search speed, with the search termination condition being T4=0. Specifically, this includes: The actual maximum speed comes from 0~v max Left boundary v left =0, v right =v max To achieve a new maximum speed The limit is half of the original, that is... , replacing v max Substitute into formulas (1)~(7) to calculate T4; if T4>0, then let v left = v right =v right If T4 < 0, then let vleft =v left v right = Then, the new maximum speed is calculated for the next round and the iteration is repeated. When T4=0, the iteration ends and the final maximum speed is obtained. ,make .

[0045] Due to the setting of the constraints, the maximum speed v in the constraints may appear. max Maximum acceleration a amax Maximum deceleration a dmax If certain parameters cannot be met, i.e., one or two, or three of the first acceleration holding time T2, the second acceleration holding time T6, and the uniform velocity time T4 are missing, then the time allocation and updating of the asymmetric S-shaped trajectory curve includes: (1) If T2=0, then execute the above-described case (a), and update T1 and T3; Figure 3a As shown; (2) If T6=0, then execute the above-described scenario (ii) and update T5 and T7; Figure 3b As shown; (3) If T4=0, then execute the above-described case (iii) and update T2 and T6; Figure 3c As shown; (4) If T2=0 and T6=0, then execute the above-described case (i) and case (ii), and update T1, T3, T5, and T7; Figure 4a As shown; (5) If T2=0 and T4=0, then execute the above-described cases (i) and (iii) to update T1, T3, and T6; Figure 4b As shown; (6) If T4=0 and T6=0, then execute the above-described cases (ii) and (iii) to update T5, T7, and T2; Figure 4c As shown; (7) If T2=0, T4=0, and T6=0, then execute the above-described case (i) and case (ii), and update T1, T3, T5, and T7; Figure 5 As shown.

[0046] Step 4: Calculate the expression for the S-shaped trajectory curve with asymmetric acceleration.

[0047] Steps 2 and 3 yield the time distribution relationships of the trajectory curves under different constraints. Next, we need to calculate the expression for the trajectory's change with time. The S-shaped trajectory curve with asymmetric acceleration has the following first-order piecewise acceleration: Formula (8)

[0048] The trajectory expression of the velocity obtained by integrating the acceleration is as follows: Formula (9)

[0049] The trajectory expression for the displacement is obtained by integrating the velocity as follows: Formula (10)

[0050] Formula (11) is: ;

[0051] Formula (12) is: ;

[0052] Formula (13) is: ;

[0053] Formula (14) is: ;

[0054] Formula (15) is: .

[0055] After planning and obtaining a continuous acceleration asymmetric S-shaped motion trajectory, it is discretized according to the sampling time interval of the motion controller to generate a series of trajectory points with fixed time steps; the motion command of the above trajectory points is sent to the controller to control the Z-axis motion of the chip mounting.

[0056] To verify that the acceleration-asymmetric S-shaped motion trajectory planned using the method described in this embodiment is smoother than the acceleration-symmetric S-shaped motion trajectory, this embodiment plans an acceleration-asymmetric S-shaped motion trajectory according to the above method, as follows: Figure 6 And according to the same parameters, a symmetrical S-shaped motion trajectory with acceleration was planned, such as... Figure 7 As shown. Among them, Figure 6 The acceleration-symmetric S-shaped trajectory shown has the parameter v. max =500mm / s, =10000mm / s 2 a dmax =7000mm / s 2 J a,amax =500000mm / s 3 J a,dmax =300000mm / s 3 J d,amax =250000mm / s 3 J d,dmax=100000mm / s 3 . Figure 7 The asymmetric S-shaped trajectory of acceleration shown has the parameter v. max =500mm / s, a amax =10000mm / s 2 a dmax =7000mm / s 2 J amax =500000mm / s 3 J dmax =123000mm / s 3 .

[0057] Both curves have the same maximum acceleration, deceleration limits, and maximum jerk. With a travel distance of 70mm, the execution time for both curves is 0.1970ms, which clearly shows... Figure 6 The asymmetric S-shaped trajectory of acceleration shown is smoother.

[0058] Please refer to Figure 8 This embodiment also provides a planning device 100 for an acceleration-asymmetric S-shaped trajectory curve, which includes: The first judgment module 1 determines whether the acceleration during the motion can reach the maximum acceleration a. amax ; The second judgment module 2 determines whether the deceleration during the motion can reach the maximum deceleration a. dmax ; The third judgment module 3 determines whether the speed can reach the maximum speed v during the motion. max ; The first calculation module 4 includes a first relation (i.e., "Formula (1)"), a second relation (i.e., "Formula (2)"), and a third relation (i.e., "Formula (3)"). The first relation is used to calculate the maximum acceleration a. amax With the maximum jerk j during the acceleration phase a,amax The acceleration rise time T1 during the acceleration phase is calculated; the second relationship is used to calculate the maximum acceleration a. amax With the maximum acceleration / deceleration j during the acceleration phase a,dmax The acceleration descent time T3 during the acceleration phase is calculated; the third relation is used to calculate the acceleration descent time T3 based on T1, T3, and v. max j a,amax The acceleration hold time T2 during the acceleration phase was calculated. The second calculation module 5 includes a fourth relation (i.e., "Formula (4)"), a fifth relation (i.e., "Formula (5)"), and a sixth relation (i.e., "Formula (6)"). The fourth relation is used to calculate the maximum deceleration a. dmaxWith the maximum acceleration j during the deceleration phase d,amax The acceleration rise time T5 during the deceleration phase is calculated; the fifth relation is used to calculate the maximum deceleration a. dmax With the maximum acceleration / deceleration j during the deceleration phase d,dmax The acceleration descent time T7 during the deceleration phase is calculated; the sixth relation is used to calculate the acceleration descent time T7 based on T5, T7, and v. max j d,amax The acceleration hold time T6 during the deceleration phase was calculated. The third calculation module 6 contains a seventh relation (i.e., "formula (7)"), which is used to calculate j a,amax j a,dmax The displacement during the acceleration phase is calculated using T1, T2, and T3. According to the maximum acceleration j during the deceleration phase d,amax j d,dmax The displacement during the deceleration phase is calculated using T5, T6, and T7. According to the total displacement S, , and maximum speed v max The time T4 of the uniform velocity phase was calculated. The first solution module 7 uses the bisection method to calculate the acceleration from 0 to the maximum acceleration a. amax Between, the maximum acceleration a in the first calculation module 4 amax Perform iterative iterations until T2=0, at which point the iteration ends and the actual maximum acceleration a is obtained. reala ; The second solution module 8 uses the bisection method to calculate the range from 0 to the maximum deceleration a. dmax Between, the maximum deceleration a in the second calculation module 5 dmax Perform iterative iterations until T6=0, at which point the iteration ends and the actual maximum deceleration a is obtained. reald ; The third solution module 9 uses the bisection method to calculate the range from 0 to the maximum velocity v. max Between these, the maximum speed v in the first calculation module 4, the second calculation module 5, and the third calculation module 6 is... max Perform iterative iterations until T4=0, at which point the iteration ends and the actual maximum speed v is obtained. real ; Planning module 10 includes an eighth relation (i.e., "Formula (8)"), a ninth relation (i.e., "Formula (9)"), and a tenth relation (i.e., "Formula (10)"). The eighth relation is used to plan the acceleration of the S-shaped trajectory curve with asymmetric acceleration; the ninth relation is used to plan the velocity of the S-shaped trajectory curve with asymmetric acceleration; and the tenth relation is used to plan the displacement of the S-shaped trajectory curve with asymmetric acceleration.

[0059] Please refer to Figure 9 This embodiment also provides a planning device for an S-shaped trajectory curve with asymmetric acceleration, which includes: Memory, used to store computer programs; A processor is used to execute computer programs to perform the following steps: S1. The first judgment module determines whether the maximum acceleration can be reached based on the input motion parameters. If it can, T1 and T3 are calculated by the first calculation module, and then step S2 is executed. Otherwise, T2 is set to zero, and the actual maximum acceleration is solved by the first solution module. The actual maximum acceleration is then input into the first calculation module as the maximum acceleration to calculate T1 and T3, and then step S2 is executed. S2. The second judgment module determines whether the maximum deceleration can be reached based on the input motion parameters. If it can, T5 and T7 are calculated by the second calculation module, and then step S3 is executed. Otherwise, T6 is set to zero, and the actual maximum deceleration is solved by the second solution module. The actual maximum deceleration is then input into the second calculation module as the maximum deceleration to calculate T5 and T7, and then step S3 is executed. S3. The third judgment module determines whether the maximum speed can be reached based on the input motion parameters. If it can, T2 and T6 are calculated by the first calculation module and the second calculation module respectively, and then step S4 is executed. Otherwise, T4 is set to zero, and the actual maximum speed is solved by the third solution module. The actual maximum speed is then used as the maximum speed and input into the first calculation module and the second calculation module to calculate T2 and T6 respectively, and then step S5 is executed. S4, the third calculation module calculates T4; S5. The planning module plans the acceleration asymmetric S-shaped trajectory curve based on T1, T2, T3, T4, T5, T6, and T7 calculated in steps S1 to S4.

[0060] This embodiment also provides a computer-readable storage medium on which a computer program is stored. When executed by a processor, the computer program performs the following steps: S1. The first judgment module determines whether the maximum acceleration can be reached based on the input motion parameters. If it can, T1 and T3 are calculated by the first calculation module, and then step S2 is executed. Otherwise, T2 is set to zero, and the actual maximum acceleration is solved by the first solution module. The actual maximum acceleration is then input into the first calculation module as the maximum acceleration to calculate T1 and T3, and then step S2 is executed. S2. The second judgment module determines whether the maximum deceleration can be reached based on the input motion parameters. If it can, T5 and T7 are calculated by the second calculation module, and then step S3 is executed. Otherwise, T6 is set to zero, and the actual maximum deceleration is solved by the second solution module. The actual maximum deceleration is then input into the second calculation module as the maximum deceleration to calculate T5 and T7, and then step S3 is executed. S3. The third judgment module determines whether the maximum speed can be reached based on the input motion parameters. If it can, T2 and T6 are calculated by the first calculation module and the second calculation module respectively, and then step S4 is executed. Otherwise, T4 is set to zero, and the actual maximum speed is solved by the third solution module. The actual maximum speed is then used as the maximum speed and input into the first calculation module and the second calculation module to calculate T2 and T6 respectively, and then step S5 is executed. S4, the third calculation module calculates T4; S5. The planning module plans the acceleration asymmetric S-shaped trajectory curve based on T1, T2, T3, T4, T5, T6, and T7 calculated in steps S1 to S4.

[0061] The computer-readable storage medium may include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0062] For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this invention, and these all fall within the protection scope of this invention.

Claims

1. A method for planning S-shaped motion trajectories with asymmetric acceleration in chip mounting, characterized in that: It comprises the following steps: Step 1 : Setting the limit conditions of the trajectory curve at the motor performance limit in reference to the motor performance parameters, including maximum speed limit v max , maximum acceleration limit a amax , maximum deceleration limit a dmax , maximum jerk J a,amax in the acceleration phase and maximum jerk J a,dmax , maximum jerk J d,amax in the deceleration phase d,dmax ; Step 2: divide the trajectory curve into seven segments of trajectories, and set the time periods of the seven segments of trajectories as follows: (1) acceleration time period: including first acceleration rising time period T1, first acceleration maintaining time period T2 and first acceleration descending time period T3; (2) uniform speed time period T4; (3) deceleration time period: including second acceleration rising time period T5, second acceleration maintaining time period T6 and second acceleration descending time period T7; Step 3: set the time period calculation formulas of the seven segments of trajectories as follows: ； ； ； ； ； ； wherein, S1 is the displacement of the acceleration time period, S2 is the displacement of the deceleration time period, S is the total displacement, total displacement S = q1 - q0, q0 is the set initial position, q1 is the final position; ； ； Step 4: update the time calculation formulas of the time periods of the seven segments of trajectories according to parameter constraints, which comprises: (1) If T2=0, then a in the time period calculation formula of the seven-segment trajectory in step 3 is replaced by amax Use the actual maximum acceleration a reala Substitute, then update T1~T7; (2) If T6=0, then a in the time period calculation formula of the seven-segment trajectory described in step 3 is replaced by dmax Use the actual maximum deceleration a reald Substitute, then update T1~T7; (3) If T4 = 0, then v max Use the actual maximum speed v real Substitute, then update T1~T7; (4) If T2=0, T6=0, then replace a in the time period calculation formula of the seven-segment trajectory in step 3 with amax Use the actual maximum acceleration a reala Replace, a dmax Use the actual maximum deceleration a reald Replace, and then update T1-T7; (5) If T2=0, T4=0, then replace a in the time period calculation formula of the seven segments trajectory in step 3 with amax Use the actual maximum acceleration a reala Replace v max Use the actual maximum speed v real Replace, and then update T1~T7; (6) If T4=0, T6=0, then replace v in the time period calculation formula of the seven-segment trajectory described in step 3 with max Use the actual maximum speed v real Replace a dmax Use the actual maximum deceleration a reald Replace, and then update T1-T7; (7) If T2=0, T4=0, T6=0, then replace a in the time period calculation formula of the seven-segment trajectory in step 3 with amax Use the actual maximum acceleration a reala Replace, and then update T1~T7; a dmax Use the actual maximum deceleration a reald Replace, and then update T1~T7; Step 5: The acceleration of the S-shaped trajectory curve with asymmetric acceleration is obtained according to the time of the seven-segment trajectory obtained in steps 3 and 4 , velocity , displacement The expressions are respectively: ； ； ； Wherein formula (11) is: ； Formula (12) is: ； Formula (13) is: ； Formula (14) is: ； Formula (15) is: 。 2. The chip-attached, acceleration-asymmetrical S-shaped trajectory planning method according to claim 1, characterized by: In the restriction condition, each parameter satisfies J a,amax J a,dmax J d,amax J d,dmax a amax a dmax .

3. The chip-attached, acceleration-asymmetrical S-shaped trajectory planning method according to claim 1, characterized by: The actual maximum acceleration a reala The calculation method is: The actual maximum acceleration comes from 0 to a amax , let left limit a aleft =0, a aright =a amax ; the new maximum acceleration is limited to the original half, namely , instead of a amax According to the calculation formula of step 3, T2 is calculated; if T2>0, let a aleft = , a aright =a aright , if T2<0, let a aleft =a aleft , a aright = , then calculate the new maximum acceleration of the next round and iterate, when T2=0, the iteration is ended, the final maximum acceleration is obtained, let .

4. The chip-attached, acceleration-asymmetric S-shaped trajectory planning method according to claim 1, characterized by: The actual maximum deceleration a reald The calculation method is: The actual maximum deceleration comes from 0~a dmax , let left limit a dleft =0, a dright =a dmax ; Let the new maximum deceleration Limit to half of the original, namely , instead of a dmax According to the calculation formula of step 3, T6 is calculated; If T6>0, let a dleft = , a dright =a dright , if T6<0, let a dleft =a dleft , a dright = , then calculate the new maximum deceleration of the next round and iterate, when T6=0, iteration ends, get the final maximum deceleration , let .

5. The chip-attached, acceleration-asymmetrical S-shaped trajectory planning method according to claim 1, characterized by: The actual maximum speed v real The calculation method is: The actual maximum speed comes from 0 to v max , set left limit v left =0, v right =v max ; Let the new maximum speed Limit to half of the original, that is , instead of v max According to the calculation formula of step 3 to get T4; If T4> 0, let v left = , v right =v right , if T4< 0, let v left =v left , v right = , then calculate the new maximum speed of the next round of iteration, when T4= 0, the iteration is finished, get the final maximum speed , let .

6. A planning device for an acceleration-asymmetric S-shaped trajectory curve, characterized by: Comprise: a first judging module judges whether the acceleration in the movement process can reach the maximum acceleration a amax ; a second judging module judges whether the deceleration in the movement process can reach the maximum deceleration a dmax ; a third judging module, judging whether the speed in the movement process can reach the maximum speed v max ; The first calculation module comprises a first relationship, a second relationship and a third relationship, the first relationship is used for calculating the acceleration rising time T1 of the acceleration stage according to the maximum acceleration a amax and the maximum jerk j a,amax of the acceleration stage, the second relationship is used for calculating the acceleration falling time T3 of the acceleration stage according to the maximum acceleration a amax and the maximum jerk j a,dmax of the acceleration stage, and the third relationship is used for calculating the acceleration holding time T2 of the acceleration stage according to T1, T3, v max and j a,amax . The second calculation module comprises a fourth relationship, a fifth relationship and a sixth relationship. The fourth relationship is used to calculate the acceleration rising time T5 of the deceleration stage according to the maximum deceleration a dmax and the maximum jerk j d,amax of the deceleration stage. The fifth relationship is used to calculate the acceleration falling time T7 of the deceleration stage according to the maximum deceleration a dmax and the maximum jerk j d,dmax of the deceleration stage. The sixth relationship is used to calculate the acceleration holding time T6 of the deceleration stage according to T5, T7, v max and j d,amax . The third calculation module comprises a seventh relationship formula, which is used for calculating the displacement of the acceleration stage according to the maximum jerk j a,amax , the maximum jerk j a,dmax , T1, T2, T3 The displacement of the deceleration stage is calculated according to the maximum jerk j d,amax , the maximum jerk j d,dmax , T5, T6, T7 The constant speed stage time T4 is calculated according to the total displacement S, , and the maximum speed v max . The planning module comprises an eighth relationship formula, a ninth relationship formula and a tenth relationship formula, the eighth relationship formula is used for planning the acceleration of the asymmetric S-shaped trajectory curve; the ninth relationship formula is used for planning the speed of the asymmetric S-shaped trajectory curve; and the tenth relationship formula is used for planning the displacement of the asymmetric S-shaped trajectory curve.

7. The apparatus for planning an acceleration-asymmetric S-shaped trajectory curve of claim 6, wherein: Also comprising: a first solving module, which uses dichotomy to make cyclic iteration for the maximum acceleration a amax in the first calculating module between 0 and the maximum acceleration a amax , and ends the iteration when T2=0, and obtains the actual maximum acceleration a reala ; a second solving module, which performs iterative calculation on the maximum deceleration a dmax in the second calculation module by using dichotomy between 0 and the maximum deceleration a dmax , and ends the iteration when T6=0, to obtain the actual maximum deceleration a reald ; a third solving module, which performs iterative calculation on the maximum speed v max between 0 and the maximum speed v max between the first, second and third calculation modules, and the iteration ends when T4=0, and the actual maximum speed v real is solved.

8. A planning device for an acceleration-asymmetric S-shaped trajectory curve, characterized by: Comprise: The memory is used for storing the computer program; The processor is used for executing the computer program to realize the asymmetric S-shaped motion trajectory planning method in chip mounting as claimed in any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that: The computer program stored on the computer readable storage medium is executed by the processor to realize the asymmetric S-shaped motion trajectory planning method in chip mounting as claimed in any one of claims 1 to 5.

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