A cluster power-on timing control method in an SMT feeder large-scale scenario

Abstract

The application discloses a cluster power-on timing control method in an SMT feeder large-scale scene. The application effectively disperses system load, avoids instantaneous large-current impact, reduces instantaneous peak current generated by synchronous power-on of a large number of devices in a large-scale scene, eliminates superimposed current impact caused by synchronous starting of the motor, and realizes orderly dispersion control of power-on timing under the premise of guaranteeing normal starting of the feeder.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-speed patch machine, in particular to a cluster power-on timing control method in SMT feeder large-scale scene. BACKGROUND

[0002] In the surface mount technology (SMT) production equipment system, the feeder cluster as the core execution unit of component supply, its power supply control logic directly affects the stability of the production line. As a key link to ensure the continuous and efficient operation of the SMT production line, the power supply control needs to balance the response speed and system safety.

[0003] At present, the industry generally adopts the "instant detection instant power supply" strategy: after the feeder is inserted into the backboard, the detection circuit identifies the connection state and triggers the power supply; after the feeder is powered on, the MCU completes the initialization and enables the motor drive without delay. This logic can meet the basic needs in a small number of feeder plug-in scenarios, and the process is simple and widely used.

[0004] However, the traditional scheme has significant limitations in large-scale scenarios. When the production line is changed, initialized or restarted, after hundreds of feeders are collectively inserted into the power backboard, the SMT host power-on will trigger the backboard to supply power to all feeders simultaneously, causing all motor drive modules to start up in a very short time. The instantaneous superposition of the starting current of all feeders forms a strong impact current with a peak value of tens of times the normal working current of a single feeder.

[0005] This instantaneous impact will cause multi-dimensional harm: first, it will cause a large fluctuation in the power bus voltage, interfering with the power supply of precision equipment such as mounting head drive and visual positioning, resulting in a decrease in running accuracy and signal transmission errors; second, the super-large instantaneous current far exceeds the rated output capacity of the backboard switching power supply, easily triggering overcurrent or over-power protection, causing power output interruption or intermittent restart, directly leading to feeder startup failure and production line initialization abnormalities; third, it shortens the average trouble-free working time of the equipment, increases the maintenance cost, reduces the production line utilization rate, and reduces the system reliability and increases the total life cycle cost, making it difficult to meet the stability requirements of high-end electronic manufacturing in large-scale scenarios. SUMMARY

[0006] In view of the deficiencies of the prior art, the purpose of the present application is to provide a cluster power-on timing control method in SMT feeder large-scale scene, which effectively disperses the system load by delaying the "power supply" and "motor enable" actions separately and using independent random time windows, avoiding the instantaneous large current impact caused by cluster synchronous power-on and feeder motor synchronous start.

[0007] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is: a cluster power-on timing control method in SMT feeder large-scale scene,

[0008] A feeder insertion detection step, after the SMT feeder is inserted into the backboard slot of the SMT feeder power backboard, the detection circuit of the SMT feeder power backboard recognizes that the SMT feeder has been connected, and the SMT feeder power backboard controls the SMT feeder to remain in a power-off state or a disconnected state;

[0009] A backboard delay power supply step, a first random delay with a true random number as a time value is generated by a true random number generator inside the backboard , and before the first random delay ends, the SMT feeder always remains in a power-off state or a disconnected state;

[0010] A feeder power-on step, after the first random delay ends, the SMT feeder power backboard supplies power to the SMT feeder, and the feeder MCU of the SMT feeder starts to boot after being powered on;

[0011] A feeder delay enable step, a second random delay with a true random number as a time value is generated by a true random number generator inside the SMT feeder immediately after the feeder MCU is powered on, and before the second random delay ends, the motor drive module is controlled to remain in a standby state, a sleep state, or a power-off state;

[0012] A motor enable step, after the second random delay ends, the motor drive module is enabled, and the motor drive module enters a working state and supplies power to the feeder motor;

[0013] The first random delay and the second random delay are generated independently of each other, and the SMT feeder power backboard delay power supply and the SMT feeder delay enable together constitute a complete double random delay control chain without additional hardware circuits and / or complex software communication protocols.

[0014] The feeder MCU controls the motor drive module to remain in a standby state, a sleep state, or a power-off state after being powered on, and first executes an embedded initialization program, and after completing the initialization program, immediately starts an embedded random delay program and generates the second random delay ,

[0015] Before the second random delay ends, the motor drive module always remains in a standby state, a sleep state, or a power-off state,

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

[0017] The SMT feeder power supply backboard delay power supply step, the SMT feeder power supply backboard starts the first TRNG module of the SMT feeder power supply backboard immediately after identifying that the SMT feeder is inserted into the backboard slot, and outputs a first random delay through the first TRNG module The value range of the first random delay is 1ms~100ms, the resolution is 0.1ms, and the number of available delay values in a single segment is: ;

[0018] The feeder delay enable step, the feeder MCU starts the second TRNG module in the internal immediately after power-on and outputs a second random delay through the second TRNG module The value range of the second random delay is 1ms~100ms, the resolution is 0.1ms, and the number of available delay values in a single segment is: ;

[0019] The SMT feeder power supply backboard and the SMT feeder use the TRNG module in the respective MCU as a true random number generator, respectively, for generating a true random value, for realizing unpredictable randomness;

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

[0021]

[0022] Among them: : The delay power supply time controlled by the SMT feeder power supply backboard;

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

[0024] : The final enable time of the first SMT feeder motor;

[0025] : The total number of SMT feeders.

[0026] The total number of enable times combined is:

[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 operation result is that the probability of the simultaneous start of at least three SMT feeders is only .

[0045] Compared with the prior art, the present application has the advantages that: by delaying the two actions of "power supply" and "motor enable" respectively and using independent random time windows, the system load is effectively dispersed, the instantaneous large current impact is avoided, the instantaneous peak current generated by the simultaneous power-on of a large number of devices in a large-scale scenario is reduced, the superimposed current impact caused by the synchronous start of the feeder motor is eliminated, and the orderly dispersed control of the power supply timing is realized on the premise of ensuring the normal start of the feeder. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 is the timing control flow chart of the power-on of the feeder and the motor enable of the feeder of the present application. DETAILED DESCRIPTION

[0047] A cluster power-on timing control method in a large-scale scenario of SMT feeders, the present application includes three parts of delay parameter design, random number generation and flow control,

[0048] First, delay parameter design.

[0049] The SMT feeder power supply backboard and the SMT feeder use the TRNG module in the MCU as a true random number generator, respectively, for generating a true random value for realizing unpredictable randomness;

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

[0051]

[0052] Among them:

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

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

[0055] is the final enable time of the motor of the first SMT feeder;

[0056] is the total number of SMT feeders;

[0057] The total number of enable times combined is: .

[0058] Second, the random number generation method.

[0059] In order to ensure the true randomness of the random number distribution, the SMT feeder power supply backboard and the SMT feeder use the hardware TRNG module (True Random Number Generator) in the respective MCU as a true random number generator to generate random values. Compared with the traditional pseudo-random algorithm, the TRNG module can provide truly unpredictable randomness based on hardware jitter, thermal noise and other physical phenomena, completely avoiding the synchronization risk caused by the predictability of the seed of the pseudo-random algorithm.

[0060] The first random delay And the second random delay The generation method is the same, and the random delay is obtained by taking the module mapping of the output of the corresponding TRNG module, and the pseudo code is as follows:

[0061] / / Generate random delay [1ms, 100ms], resolution 0.1ms

[0062] float generate_random_delay()

[0063] {

[0064] uint16_t rand_val = trng_get_value() % 991; / / TRNG generates 0~990

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

[0066] }

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

[0068] The pseudo code of 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 receiving power, the SMT feeder is powered; 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 cluster power-on timing control method in an SMT feeder large-scale scene, the specific control steps are as follows:

[0081] Step S1, feeder insertion detection step, when the SMT feeder is inserted into the corresponding backboard slot of the SMT feeder power supply backboard along the preset guide rail of the SMT equipment, the SMT feeder power supply backboard detection circuit responds in time, and the SMT feeder is verified and confirmed to be reliably inserted into the backboard slot, that is, the SMT feeder power supply backboard detection circuit identifies that the SMT feeder has been connected, and the SMT feeder power supply backboard controls the SMT feeder to remain in a power-off state or a disconnected state.

[0082] Step S2, backboard delay power supply step, after identifying the insertion of the SMT feeder, the SMT feeder power supply backboard does not immediately power on the SMT feeder, but starts a random delay timer through internal control logic, specifically, a first random delay with a true random number value is generated by a true random number generator inside the backboard. Before the end of the first random delay , the SMT feeder always remains in a power-off state or a disconnected state.

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

[0084] Feeder power-on step, after the end of the first random delay , the SMT feeder power supply backboard supplies power to the SMT feeder, the SMT feeder power supply backboard connects the power supply to the SMT feeder power supply interface, the SMT feeder power supply indicator light is on, the SMT feeder MCU starts after being powered on, and the SMT feeder internal power management module starts to work. The feeder enters a power-on standby state.

[0085] Feeder delay enable step, the feeder MCU controls the motor drive module to remain in a standby state, a sleep state or a power-off state after being powered on, the feeder MCU executes the built-in initialization program after being powered on, including hardware self-checking and parameter configuration operations, and generates the second random delay after completing the initialization program, and the motor drive module always remains in a standby state, a sleep state or a power-off state before the end of the second random delay .

[0086] Specifically, a second random delay with a true random number as a time length value is generated by a true random number generator inside the SMT feeder , and the motor driving module is controlled to remain in a standby state, a sleep state or a power-off state before the second random delay ends; the second TRNG module is a hardware TRNG module integrated in the MUC of the SMT feeder, the second TRNG module serves as a true random number generator, and a second random delay is obtained by outputting a modulo mapping through the second TRNG module , the value range of the second random delay is 1ms~100ms, the resolution is 0.1ms, and the number of available delay values in a single segment is: .

[0087] The motor enabling step, after the second random delay ends, the feeder MCU opens the motor driving module, enables the motor driving module and starts to enable the motor driving module, the motor driving module enters a working state and outputs a driving current to drive the feeder motor shaft, and the SMT feeder enters a normal material conveying working mode.

[0088] The application also includes a probability estimation step,

[0089] The ball and box model is used for modeling, the Poisson distribution approximation method is used for probability estimation, and the condition of “at least three SMT feeders being powered on at the same time” is used for estimation,

[0090] regarding SMT feeders as independent events,

[0091] the final motor enabling time of each SMT feeder,

[0092] the total number of two segments of delay that can be used is: ,

[0093] The above equivalence is “128 balls are randomly thrown into T boxes”, and the probability of the event “exactly k balls in a certain box” is , then:

[0094]

[0095] For “at least three SMT feeders being powered on at the same time”, there are , since is much larger than , it is simplified as:

[0096]

[0097] Substituting the numerical values into the equation:

[0098]

[0099]

[0100]

[0101] The probability of at least 3 SMT feeders being activated simultaneously is only .

Claims

1. A method for cluster power-on timing control in a large-scale SMT feeder scenario, characterized in that: The method comprises the following steps, The SMT feeder power supply backboard controls the SMT feeder to remain in a power-off state or a disconnected state after the SMT feeder is inserted into the backboard slot of the SMT feeder power supply backboard and the detection circuit of the SMT feeder power supply backboard identifies that the SMT feeder has been connected; The backboard delay power supply step generates a first random delay with a true random number of time length value through a true random number generator inside the backboard And before the first random delay The SMT feeder always remains in a power-off state or a disconnected state before the timing ends The feeder power-on step, after a first random delay After the timing ends, the SMT feeder power supply backboard supplies power to the SMT feeder, and the feeder MCU of the SMT feeder starts to boot after being powered on; The feeder delay enable step starts a random delay immediately after the feeder MCU is powered on, and a second random delay with a time length value of a true random number is generated by a true random number generator inside the SMT feeder And before the second random delay The motor drive module is controlled to remain in a standby state, a sleep state or a power-off state before the timing ends Motor enable step, after second random delay After the timing ends, the motor drive module is enabled, and the motor drive module enters a working state and supplies power to the feeder motor. The first random delay The second random delay The first random delay and the second random delay are independently generated, and the SMT feeder power supply backplane delay power supply and the SMT feeder delay enable jointly constitute a complete double random delay control chain without additional hardware circuit and / or complex software communication protocol.

2. The cluster power-on timing control method in SMT feeder mass production scenarios according to claim 1, characterized in that: The feeder MCU controls the motor drive module to remain in a standby state, a sleep state or a power-off state after being powered on, and first executes an internal initialization program, and immediately starts an internal random delay program and generates the second random delay after completing the initialization program , At the second random delay The motor drive module is always kept in a standby state, a sleep state or a power-off state before the timing ends, At 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 the drive current to drive the feeder motor lock shaft, and the SMT feeder enters the normal material conveying working mode.

3. The cluster power-on timing control method in the SMT feeder large-scale scenario according to claim 1, characterized in that: The SMT feeder power supply backboard delay power supply step, the SMT feeder power supply backboard starts the first TRNG module of the SMT feeder power supply backboard immediately after identifying that the SMT feeder is inserted into the backboard slot, and outputs a first random delay through the first TRNG module , the value range of the first random delay is 1ms~100ms, the resolution is 0.1ms, and the number of available delay values in a single segment is: ; The feeder delay enabling step, the feeder MCU starts the internal second TRNG module immediately after power on and outputs a second random delay through the second TRNG module , the second random delay The value range of the second random delay is 1ms~100ms, the resolution is 0.1ms, and the number of available delay values in a single segment is: ; The SMT feeder power supply backboard and the SMT feeder use respective TRNG modules in the MCUs as true random number generators to generate true random values and realize unpredictable randomness; The final motor enable time of the motor drive module is: ； wherein: : SMT feeder power backplane controlled delay power time; : SMT feeder internal control delay enable time; : the first SMT feeder motor final enable time; : number of total SMT feeders; The total number of enabling moments combined Is: 。 4. The cluster power-on timing control method in SMT feeder mass production scenarios according to claim 1, characterized in that: the first random delay and the second random delay are generated in the same way, the generation method being that The pseudo code of the function float generate_random_delay() is used to output the modulo mapping, the original random number is obtained from the corresponding hardware TRNG module through the interface trng_get_value(), and then the modulo operation is performed to constrain the integer range of 0-990, and finally the linear transformation is performed to map the delay value to the floating-point type of 1.0ms to 100.0ms, so as to ensure that each possible delay value is uniformly distributed in statistics; The first TRNG module is a hardware TRNG module integrated in the MUC of the SMT feeder power supply backboard; The second TRNG module is a hardware TRNG module integrated in the MUC of the SMT feeder.

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