Cluster power-on time sequence control method in SMT (Surface Mount Technology) feeder large-scale scene

Abstract

The invention discloses a cluster power-on time sequence control method in an SMT (Surface Mount Technology) feeder large-scale scene, which is characterized in that two actions of power supply and motor enabling are respectively delayed, and an independent random time window is used, so that the system load is effectively dispersed, the instantaneous large current impact is avoided, and the service life of the system is prolonged. Instantaneous peak current generated by synchronous power-on of a large number of devices in a large-scale scene is reduced, superimposed current impact caused by synchronous starting of a motor is eliminated, and ordered decentralized control over the power supply time sequence is achieved on the premise that normal starting of a feeder is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of high-speed pick and place machine technology, and in particular to a cluster power-on timing control method for large-scale SMT feeder scenarios. Background Technology

[0002] In surface mount technology (SMT) production equipment systems, the feeder cluster serves as the core execution unit for component supply, and its power supply control logic directly impacts the stability of the production line. As a crucial link in ensuring the continuous and efficient operation of the SMT production line, power supply control must balance response speed and system safety.

[0003] Currently, the industry generally adopts a "real-time detection and real-time power supply" strategy: after the feeder is inserted into the backplane, the detection circuit identifies the connection status and triggers power supply; after the feeder is powered on, the MCU completes initialization and enables motor drive without delay. This logic can meet basic requirements in scenarios with a small number of feeder insertions and removals, and its simple process has led to its widespread application.

[0004] However, traditional solutions have significant limitations in large-scale scenarios. When the production line is changed, initialized, or restarted, hundreds of feeders are inserted into the power backplane. When the SMT host is powered on, it triggers the backplane to synchronously supply power to all feeders, causing all motor drive modules to start up simultaneously in a very short time. The starting current of all feeders is instantaneously superimposed, forming a strong surge current with a peak value tens of times that of a single feeder's normal operating current.

[0005] Such instantaneous shocks can cause multi-dimensional harm: First, they can cause large fluctuations in the power bus voltage, interfering with the power supply of precision equipment such as placement head drive and vision positioning, leading to decreased operating accuracy and signal transmission errors; Second, the ultra-large instantaneous current far exceeds the rated output capacity of the backplane switching power supply, easily triggering overcurrent or overpower protection, causing power output interruption or intermittent restart, directly leading to feeder startup failure and abnormal production line initialization; Third, they can shorten the mean time between failures (MTBF) of the equipment, increase maintenance costs, reduce production line uptime, reduce system reliability, increase the total life cycle cost, and make it difficult to meet the stability requirements of high-end electronic manufacturing in large-scale scenarios. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a cluster power-on timing control method for large-scale SMT feeder applications. This method addresses the power supply system impact caused by synchronous power-on of the cluster and synchronous startup of the feeder motors. By delaying the "power supply" and "motor enable" actions separately and using independent random time windows, the system load is effectively distributed, avoiding instantaneous high current surges.

[0007] To achieve the above objectives, the technical solution adopted by this invention is: a cluster power-on timing control method for large-scale SMT feeder scenarios.

[0008] In the feeder insertion detection step, after the SMT feeder is inserted into the backplane slot of the SMT feeder power supply backplane, the detection circuit of the SMT feeder power supply backplane recognizes that the SMT feeder is connected, and the SMT feeder power supply backplane controls the SMT feeder to remain in the power-off state or disconnected state.

[0009] The backplane delayed power supply step involves generating a first random delay with a duration of a truly random number using a true random number generator inside the backplane. and during the first random delay The SMT feeder remains in a power-off or disconnected state until the timing ends.

[0010] The power-on procedure for the feeder is as follows: During the first random delay... After the timing ends, the SMT feeder power supply backplane supplies power to the SMT feeder, and the feeder MCU of the SMT feeder starts up after being powered on.

[0011] The feeder delay enable step involves immediately initiating a random delay after the feeder MCU is powered on. This is achieved by generating a second random delay with a truly random duration using the true random number generator inside the SMT feeder. and in the second random delay Before the timing ends, the motor drive module is kept in standby, hibernation, or power-off state.

[0012] The motor enable step, during the second random delay After the timing ends, the motor drive module is enabled, and the motor drive module enters the working state and supplies power to the feeder motor.

[0013] First random delay Second random delay They are generated independently of each other, and the SMT feeder power supply backplane delay power supply and SMT feeder delay enable together form a complete dual random delay control chain that does not require additional hardware circuits and / or complex software communication protocols.

[0014] After being powered on, the feeder MCU controls the motor drive module to remain in standby, sleep, or power-off state, and first executes the built-in initialization program. After the initialization program is completed, the built-in random delay program is immediately started and the second random delay is generated. ,

[0015] Second random delay The motor drive module remains in standby, sleep, or power-off state until the timing ends.

[0016] Second random delay After the timing ends, the feeder MCU turns on the motor drive module and enables the motor drive module. The motor drive module enters the working state and outputs drive current to drive the feeder motor to lock the shaft. The SMT feeder enters the normal material conveying working mode.

[0017] The SMT feeder power supply backplane delayed power supply step involves the SMT feeder power supply backplane immediately activating its first TRNG module after recognizing the SMT feeder inserted into the backplane slot, and obtaining a first random delay by outputting a modulus mapping through the first TRNG module. First random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: ;

[0018] In the feeder delay enable step, the feeder MCU immediately starts its internal second TRNG module after power-on and obtains a second random delay by outputting a modulus mapping through the second TRNG module. Second random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: ;

[0019] The SMT feeder power supply backplane and the SMT feeder each use their own MCU's internal TRNG module as a true random number generator to generate true random values ​​and achieve unpredictable randomness.

[0020] The final motor enable time of the motor drive module is:

[0021]

[0022] in: Delay power supply time controlled by the SMT feeder power supply backplane;

[0023] The delay enable time controlled internally by the SMT feeder;

[0024] : No. Final enable time of each SMT feeder motor;

[0025] Total number of SMT feeders.

[0026] Total number of enable times combined for:

[0027] .

[0028] First random delay Second random delay The generation method is the same as that for the other two, which is:

[0029] The pseudocode is obtained by outputting the modulo mapping using the function float generate_random_delay(). The original random number is obtained from the corresponding hardware TRNG module through the interface trng_get_value(). Then, the modulo operation is performed to constrain it to the integer range of 0-990. Finally, a linear transformation is performed to map it to a floating-point delay value of 1.0ms to 100.0ms, ensuring that each possible delay value is statistically uniformly distributed.

[0030] The first TRNG module is a hardware TRNG module integrated into the power supply backplane of the SMT feeder in the MUC.

[0031] The second TRNG module is a hardware TRNG module integrated into the MUC of the SMT feeder.

[0032] It also includes a probability estimation step, which uses a sphere and box model for modeling, employs the Poisson distribution approximation method for probability estimation, and performs the estimation based on the condition that "at least three SMT feeders are powered on simultaneously".

[0033] Will Each SMT feeder is treated as an independent event.

[0034] Final motor enable time for each SMT feeder ,

[0035] The total number of usable delay segments is: ,

[0036] The above is equivalent to "128 balls are randomly dropped into T boxes", where the probability of the event "a certain box contains exactly k balls" is given by... ,but:

[0037]

[0038] Regarding "at least 3 SMT feeders powered on simultaneously", there are ,because Much larger Simplified to:

[0039]

[0040] Substitute the values ​​into the calculation:

[0041]

[0042]

[0043]

[0044] The calculation result shows that the probability of at least three SMT feeders starting simultaneously is only [percentage missing]. .

[0045] The advantages of this invention compared with the prior art are: by delaying the two actions of "power supply" and "motor enable" respectively and using independent random time windows, this invention effectively distributes the system load, avoids instantaneous large current surges, reduces the instantaneous peak current generated by the synchronous power-on of a large number of devices in large-scale scenarios, eliminates the superimposed current surge caused by the synchronous start-up of the feeder motor, and achieves orderly distributed control of power supply timing while ensuring the normal start-up of the feeder. Attached Figure Description

[0046] Figure 1 This is a flowchart of the timing control for powering on the feeder and enabling the feeder motor according to the present invention. Detailed Implementation

[0047] A method for cluster power-on timing control in large-scale SMT feeder scenarios. This invention comprises three parts: delay parameter design, random number generation, and process control.

[0048] First, delay parameter design.

[0049] The SMT feeder power supply backplane and the SMT feeder each use their own MCU's internal TRNG module as a true random number generator to generate true random values ​​and achieve unpredictable randomness.

[0050] The final motor enable time for the motor drive module is:

[0051]

[0052] in:

[0053] It is the delay power supply time controlled by the SMT feeder power supply backplane;

[0054] It is the delay enable time controlled internally by the SMT feeder;

[0055] It is the first Final enable time of each SMT feeder motor;

[0056] This is the total number of SMT feeders;

[0057] Total number of enable times combined for: .

[0058] Second, random number generation methods.

[0059] To ensure true randomness in the random number distribution, the SMT feeder power supply backplane and the SMT feeder each use their respective MCU's built-in hardware TRNG (True Random Number Generator) module as true random number generators to generate random values. Compared to traditional pseudo-random algorithms, the TRNG module, based on physical phenomena such as hardware jitter and thermal noise, can provide truly unpredictable randomness, completely avoiding the synchronization risks caused by the predictability of seeds in pseudo-random algorithms.

[0060] First random delay Second random delay The generation method is the same, and the random delay is obtained by modulo mapping of the output of the corresponding TRNG module. The pseudocode is as follows:

[0061] / / Generate random delays [1ms, 100ms] with a resolution of 0.1ms

[0062] float generate_random_delay()

[0063] {

[0064] uint16_t rand_val = trng_get_value() % 991; / / TRNG generates values ​​from 0 to 990

[0065] return 1.0f + 0.1f * rand_val; / / Map to delay

[0066] }

[0067] The above pseudocode describes the implementation method as follows: the original random number is obtained from the hardware TRNG module through the interface function trng_get_value(), constrained to the integer range of 0-990 by modulo operation, and then mapped to a floating-point delay value of 1.0ms to 100.0ms through linear transformation, ensuring that each possible delay value is statistically uniformly distributed.

[0068] The pseudocode for the SMT feeder initialization process is as follows:

[0069] void feeder_power_on()

[0070] {

[0071] hardware_init();

[0072] float local_delay = generate_random_delay();

[0073] delay_ms(local_delay); / / Delay the execution of the action

[0074] motor_enable(); / / Enable motor

[0075] }

[0076] The implementation method described in the above initialization code is as follows: the SMT feeder first calls the random delay generation function generate_random_delay() to obtain the motor enable delay time, ensuring that the randomness of the delays is independent of each other. By completing hardware initialization before performing the motor enable delay, this step-by-step execution mechanism effectively isolates operational interference at different stages, further enhancing the accuracy and effectiveness of the random delay.

[0077] Third, initiate process control.

[0078] The startup process of this invention is based on the collaborative implementation of two independent functional modules: the SMT feeder power supply backplane and the SMT feeder. It achieves staggered startup of the SMT feeder cluster through a dual random delay control mechanism.

[0079] After the SMT feeder is inserted into the backplane slot, the SMT feeder power backplane does not immediately supply power, but instead sets a random delay time. After that, power is supplied to the SMT feeder; after the SMT feeder receives power, the feeder MCU does not immediately enable the motor, but sets another random delay time ( Then the motor is enabled; both delays are generated independently within the configurable range, forming a complete two-stage power supply action to achieve concurrent peak-shaving start-up; the two modules are independent of each other, with the first random delay... Second random delay The two systems are generated independently, with the SMT feeder power supply backplane delay power supply and SMT feeder delay enable forming a complete dual random delay control chain. This eliminates the need for additional hardware circuits and / or complex software communication protocols, simplifying the system architecture and ensuring the real-time performance and reliability of the control process. It effectively solves the current surge problem when powering on a large-scale SMT feeder cluster. The method of this invention can be widely applied to embedded control scenarios where large-scale parallel power supply and instantaneous startup may cause system surges. It is particularly suitable for use in high-density SMT feeder systems. This invention solves the problem of excessive current surge when powering on a medium-density SMT feeder cluster in existing systems.

[0080] A method for cluster power-on timing control in a large-scale SMT feeder scenario, the specific control steps are as follows:

[0081] Step S1, Feeder Insertion Detection Step: When the SMT feeder is inserted into the corresponding backplane slot of the SMT feeder power supply backplane along the preset guide rail of the SMT equipment, the SMT feeder power supply backplane detection circuit responds immediately. After verification, it is confirmed that the SMT feeder has been reliably inserted into the backplane slot. That is, the detection circuit of the SMT feeder power supply backplane recognizes that the SMT feeder is connected, and the SMT feeder power supply backplane controls the SMT feeder to remain in the power-off state or disconnected state.

[0082] Step S2, Backplane Delayed Power Supply Step: After recognizing the insertion of the SMT feeder, the SMT feeder power supply backplane does not immediately power on the SMT feeder. Instead, it starts a random delay timer through internal control logic. Specifically, a first random delay with a duration of a truly random number is generated by the true random number generator inside the backplane. and during the first random delay The SMT feeder remains powered off or disconnected until the timing ends.

[0083] The true random number generator is the first TRNG module of the SMT feeder power supply backplane. The first TRNG module is a hardware TRNG module integrated into the MUC of the SMT feeder power supply backplane. A first random delay is obtained by outputting a modulo mapping through the first TRNG module. First random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: .

[0084] The power-on procedure for the feeder is as follows: During the first random delay... After the timing ends, the SMT feeder power supply backplane supplies power to the SMT feeder. The SMT feeder power supply backplane connects the power supply to the SMT feeder power supply interface, the SMT feeder power indicator light illuminates, the SMT feeder MCU starts up after power-on, the SMT feeder internal power management module starts working, and the feeder enters the power-on standby state.

[0085] The feeder delay enable step involves the feeder MCU controlling the motor drive module to remain in standby, sleep, or power-off state after power-on. Upon receiving power, the feeder MCU first executes its built-in initialization program, including hardware self-test and parameter configuration. After completing the initialization program, the feeder MCU immediately starts its built-in random delay program and generates the second random delay. and in the second random delay The motor drive module remains in standby, hibernation, or power-off state until the timing ends.

[0086] Specifically, a second random delay with a truly random duration is generated by the true random number generator inside the SMT feeder. and in the second random delay Before the timing ends, the motor drive module is kept in standby, sleep, or power-off state; the second TRNG module is a hardware TRNG module integrated into the SMT feeder's MUC. The second TRNG module acts as a true random number generator, and a second random delay is obtained by taking the modulo mapping from the output of the second TRNG module. Second random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: .

[0087] The motor enable step, during the second random delay After the timing ends, the feeder MCU turns on the motor drive module and enables the motor drive module. The motor drive module enters the working state and outputs drive current to drive the feeder motor lock shaft. The SMT feeder enters the normal material conveying working mode.

[0088] The present invention also includes a probability estimation step.

[0089] A sphere-and-box model was used for modeling, and a Poisson distribution approximation method was employed for probability estimation. The estimation was based on the condition that "at least three SMT feeders are powered on simultaneously."

[0090] Will Each SMT feeder is treated as an independent event.

[0091] Final motor enable time for each SMT feeder ,

[0092] The total number of usable delay segments is: ,

[0093] The above is equivalent to "128 balls are randomly dropped into T boxes", where the probability of the event "a certain box contains exactly k balls" is given by... ,but:

[0094]

[0095] Regarding "at least 3 SMT feeders powered on simultaneously", there are ,because Much larger Simplified to:

[0096]

[0097] Substitute the values ​​into the calculation:

[0098]

[0099]

[0100]

[0101] The calculation result shows that the probability of at least three SMT feeders starting simultaneously is only [percentage missing]. .

Claims

1. A method for cluster power-on timing control in a large-scale SMT feeder scenario, characterized in that: Includes the following steps, In the feeder insertion detection step, after the SMT feeder is inserted into the backplane slot of the SMT feeder power supply backplane, the detection circuit of the SMT feeder power supply backplane recognizes that the SMT feeder is connected, and the SMT feeder power supply backplane controls the SMT feeder to remain in the power-off state or disconnected state. The backplane delayed power supply step involves generating a first random delay with a duration of a truly random number using a true random number generator inside the backplane. and during the first random delay The SMT feeder remains in a power-off or disconnected state until the timing ends. The power-on procedure for the feeder is as follows: During the first random delay... After the timing ends, the SMT feeder power supply backplane supplies power to the SMT feeder, and the feeder MCU of the SMT feeder starts up after being powered on. The feeder delay enable step involves immediately initiating a random delay after the feeder MCU is powered on. This is achieved by generating a second random delay with a truly random duration using the true random number generator inside the SMT feeder. and in the second random delay Before the timing ends, the motor drive module is kept in standby, hibernation, or power-off state. The motor enable step, during the second random delay After the timing ends, the motor drive module is enabled, and the motor drive module enters the working state and supplies power to the feeder motor. First random delay Second random delay They are generated independently of each other, and the SMT feeder power supply backplane delay power supply and SMT feeder delay enable together form a complete dual random delay control chain that does not require additional hardware circuits and / or complex software communication protocols.

2. The method for cluster power-on timing control in a large-scale SMT feeder scenario according to claim 1, characterized in that: After being powered on, the feeder MCU controls the motor drive module to remain in standby, sleep, or power-off state, and first executes the built-in initialization program. After the initialization program is completed, the built-in random delay program is immediately started and the second random delay is generated. , Second random delay The motor drive module remains in standby, sleep, or power-off state until the timing ends. Second random delay After the timing ends, the feeder MCU turns on the motor drive module and enables the motor drive module. The motor drive module enters the working state and outputs drive current to drive the feeder motor to lock the shaft. The SMT feeder enters the normal material conveying working mode.

3. The method for cluster power-on timing control in a large-scale SMT feeder scenario according to claim 1, characterized in that: The SMT feeder power supply backplane delayed power supply step involves the SMT feeder power supply backplane immediately activating its first TRNG module after recognizing the SMT feeder inserted into the backplane slot, and obtaining a first random delay by outputting a modulus mapping through the first TRNG module. First random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: ; In the feeder delay enable step, the feeder MCU immediately starts its internal second TRNG module after power-on and obtains a second random delay by outputting a modulus mapping through the second TRNG module. Second random delay The value range is 1ms to 100ms, the resolution is 0.1ms, and the number of available delay values ​​per segment is: ; The SMT feeder power supply backplane and the SMT feeder each use their own MCU's internal TRNG module as a true random number generator to generate true random values ​​and achieve unpredictable randomness. The final motor enable time of the motor drive module is: in: Delay power supply time controlled by the SMT feeder power supply backplane; The delay enable time controlled internally by the SMT feeder; : No. Final enable time of each SMT feeder motor; Total number of SMT feeders; Total number of enable times combined for: 。 4. The method for cluster power-on timing control in a large-scale SMT feeder scenario according to claim 1, characterized in that: First random delay Second random delay The generation method is the same as that for the other two, which is: The pseudocode is obtained by outputting the modulo mapping using the function float generate_random_delay(). The original random number is obtained from the corresponding hardware TRNG module through the interface trng_get_value(). Then, the modulo operation is performed to constrain it to the integer range of 0-990. Finally, a linear transformation is performed to map it to a floating-point delay value of 1.0ms to 100.0ms, ensuring that each possible delay value is statistically uniformly distributed. The first TRNG module is a hardware TRNG module integrated into the power supply backplane of the SMT feeder in the MUC. The second TRNG module is a hardware TRNG module integrated into the MUC of the SMT feeder.

5. The method for cluster power-on timing control in a large-scale SMT feeder scenario according to claim 1, characterized in that: It also includes a probability estimation step. A sphere-and-box model is used for modeling, and a Poisson distribution approximation method is employed for probability estimation, based on the condition that "at least three SMT feeders are powered on simultaneously". Will Each SMT feeder is treated as an independent event. Final motor enable time for each SMT feeder , The total number of usable delay segments is: , The above is equivalent to "128 balls are randomly dropped into T boxes", where the probability of the event "a certain box contains exactly k balls" is given by... ,but: Regarding "at least 3 SMT feeders powered on simultaneously", there is... ,because Much larger Simplified to: Substitute the values ​​into the calculation: The calculation result shows that the probability of at least three SMT feeders starting simultaneously is only [percentage missing]. .

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