AGV dual-mode remote switch-on and switch-off control circuit and method based on ESP32

Abstract

The application provides an AGV dual-mode remote on-off control circuit and method based on ESP32, which comprises an original manual rotary switch SA connected in series in an AGV main loop; a normally closed relay K, whose normally closed contact is connected in series between the SA and the coil of an AGV main contactor KM, and the on-off of the K is controlled by an ESP32 module; the auxiliary normally open contact of the KM is connected in parallel with the coil to form a self-locking loop; the ESP32 module receives the instructions of a dispatching system through Wi-Fi, controls the on-off of the K, and collects the state of the auxiliary contact of the KM to form a closed loop feedback; a power module takes power from a storage battery, and the power taking point is located at the front end of the KM to ensure that the ESP32 still maintains power supply after the shutdown. The application can realize remote dual-mode control by only connecting a normally closed relay in series in the coil loop of the original AGV main contactor, and the hardware modification is small; the manual switch has the highest priority of physical cut-off, and the system can be automatically reset through the manual switch operation when the remote module is abnormal; the AGV main control is cooperated to shut down through CAN, so that the damage caused by abnormal power-off is avoided.

Description

Technical Field

[0001] This invention relates to the field of automated logistics AGV technology, specifically to an AGV dual-mode remote start-up and shutdown control circuit and method based on ESP32, which is suitable for remote centralized start-up and shutdown control of a large number of AGVs in a factory. Background Technology

[0002] With the rapid development of smart manufacturing and Industry 4.0, automated guided vehicles (AGVs) have been widely used in factory logistics systems. In modern smart factories, the number of AGVs often reaches dozens or even hundreds, becoming the core equipment for material handling within the factory.

[0003] Currently, AGV (Automated Guided Vehicle) operation is generally done manually, requiring operators to walk to each AGV and turn it on or off by rotating a mechanical switch. When a factory has hundreds of AGVs, the daily startup and shutdown require a significant amount of manpower and time, resulting in extremely low operational efficiency and severely hindering the factory's maintenance efficiency. Furthermore, this manual, one-by-one operation method is ill-suited to the demands of modern factories for intelligent equipment management.

[0004] To address the aforementioned issues, several retrofit solutions for remote AGV start-up and shutdown have been proposed in the existing technology. However, these solutions generally suffer from the following shortcomings: First, some existing solutions require replacing the entire set of original switch components of the AGV, which is costly, has a long implementation cycle, and requires significant modifications to the original electrical system of the AGV, posing a high implementation risk.

[0005] Second, some solutions require the construction of complex interlocking circuits to switch between remote and local control. The circuit structure is complex, the reliability is difficult to guarantee, and the number of system failure points is increased.

[0006] Third, in existing remote start-up and shutdown solutions, if the remote control module malfunctions (such as crashing or program crashing), it may cause abnormal relay status, preventing the entire vehicle from starting or stopping normally, lacking necessary emergency redundancy. Operators cannot restore control of the AGV through traditional manual methods when the remote module fails, severely impacting production continuity.

[0007] Fourth, existing remote control modules often continue to consume power even when the AGV is powered off. If the AGV is parked for a long time, the continuous power consumption of the remote module will cause the AGV battery to be over-discharged, shortening the battery life or even causing battery damage.

[0008] Fifth, in existing solutions, remote shutdown operations often directly cut off the AGV's main power supply without coordinating with the AGV's main control system. This may lead to data loss, file system corruption, or even hardware failure in the AGV's main control system due to abnormal power outages, affecting the lifespan of the AGV's core components and the system's reliability.

[0009] Therefore, there is an urgent need in this field for a remote AGV start-up and shutdown control solution that requires minimal hardware modifications, has low transformation costs, high reliability, emergency redundancy capabilities, low standby power consumption, and can work in conjunction with the AGV main controller. Summary of the Invention

[0010] To address the aforementioned shortcomings in existing AGV remote power on / off control technologies, this invention provides an ESP32-based dual-mode remote power on / off control circuit and method for AGVs that is easy to modify, has high safety redundancy, and operates with low power consumption. This method can solve the problems of low efficiency in power on / off operations of large AGV clusters, the inability of the entire vehicle to operate due to remote module failure, and excessive power consumption of the remote module when the vehicle is off.

[0011] The present invention achieves the above objectives through the following technical solutions: A dual-mode remote start / stop control circuit for AGV based on ESP32, comprising: The original manual rotary switch SA was connected in series in the AGV main circuit to enable manual physical disconnection of the AGV main circuit power supply. The normally closed relay K has its normally closed contacts connected in series between the output terminal of the manual rotary switch SA and the coil of the AGV main contactor KM. The coil is controlled by the ESP32 module to open and close. The AGV main contactor KM has its coil connected in series between the normally closed contact of the normally closed relay K and the power supply circuit. The auxiliary normally open contact of the AGV main contactor KM is connected in parallel with its own coil, forming a self-locking circuit. The self-locking circuit allows the AGV main contactor KM to remain continuously engaged by the brief closing of the manual rotary switch SA or the normally closed relay K. The ESP32 module receives power-on / off commands from the scheduling system via Wi-Fi, controls the coil opening and closing of the normally closed relay K according to the power-on / off commands, and collects the auxiliary contact status of the AGV main contactor KM to confirm the actual power status feedback of the AGV. The power module draws power from the AGV battery and converts it into low-voltage DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The power module draws power from the front end of the AGV main contactor KM, so that the ESP32 module continues to be powered even after the AGV main contactor KM is disconnected.

[0012] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. The normally closed relay K remains in a normally closed state when the ESP32 module is not powered on or has not received a shutdown command, ensuring that the AGV main contactor KM can be directly energized and started when the manual rotary switch SA is closed. When the ESP32 module receives a shutdown command, it drives the coil of the normally closed relay K to open its normally closed contacts, cutting off the power supply circuit of the coil of the AGV main contactor KM, thereby realizing remote shutdown. When the ESP32 module receives a start-up command or recovers from an abnormal state, it releases the coil of the normally closed relay K to close its normally closed contacts again, restoring the control path of the manual rotary switch SA to the AGV main contactor KM.

[0013] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. The GPIO port of the ESP32 module is connected to the coil of a normally closed relay K through an optocoupler isolation drive circuit. The optocoupler isolation drive circuit includes an optocoupler and a driving transistor. The input side of the optocoupler is connected to the GPIO port of the ESP32 module through a current-limiting resistor, and the output side of the optocoupler is connected to the control electrode of the driving transistor. The driving transistor is connected in series in the power supply circuit of the normally closed relay K coil. The optocoupler isolation drive circuit is used to realize electrical isolation between the low-voltage control signal of the ESP32 module and the driving circuit of the normally closed relay K coil, so as to suppress the influence of electromagnetic interference in the AGV high-voltage circuit on the ESP32 module and enhance the driving capability of the GPIO port to the coil of the normally closed relay K.

[0014] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. The power supply module includes a wide-input DC-DC step-down chip. The input terminal of the wide-input DC-DC step-down chip is connected to the output terminal of the AGV battery and the connection point is located at the front end of the AGV main contactor KM. The output terminal of the wide-input DC-DC step-down chip outputs 3.3V DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The ESP32 module has a built-in Wi-Fi wake-up sleep mode. When the ESP32 module completes the remote shutdown operation and confirms that the actual power status of the AGV is off, the ESP32 module immediately enters the Wi-Fi wake-up sleep mode. In sleep mode, the ESP32 module shuts down unnecessary functional modules and peripherals, and only retains the minimum working circuit of the Wi-Fi receiving link to listen for the wake-up command of the scheduling system. When the ESP32 module is in sleep mode, the coil of the normally closed relay K is in the de-energized and released state, and its normally closed contact remains closed. At this time, if the manual rotary switch SA is manually turned to ON, the coil of the AGV main contactor KM is energized by the normally closed contact of the normally closed relay K, and the AGV is powered on and started normally.

[0015] According to the present invention, a dual-mode remote power on / off control circuit for AGV based on ESP32 is provided, wherein a pair of auxiliary normally open contacts of the AGV main contactor KM are connected to the GPIO port of the ESP32 module to provide feedback on the actual power status of the AGV to the ESP32 module. The ESP32 module has a built-in status synchronization verification logic, which compares the expected relay status recorded inside the ESP32 module with the actual power status of the AGV collected through the auxiliary normally open contact in real time. When the expected relay status is inconsistent with the actual power status of the AGV, the ESP32 module determines that there is an abnormal status and performs a status self-recovery operation.

[0016] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. When the desired relay state is ON but the actual power supply state of the AGV is OFF, it indicates that the normally closed relay K is actually open due to an abnormal reason. The ESP32 module immediately re-drives the coil of the normally closed relay K to restore its normally closed contacts to close, thereby eliminating the state deviation and realizing system self-recovery. When the desired relay state is OFF but the actual power supply state of the AGV is ON, it indicates that the AGV main contactor KM has not disconnected normally due to an abnormal reason. The ESP32 module reports alarm information to the scheduling system. The status acquisition of the auxiliary normally open contact is also used to confirm the execution result of remote power on / off operations. The ESP32 module only returns a successful operation response after confirming that the actual power status of the AGV is consistent with the target status through the auxiliary normally open contact, thus forming a closed-loop control.

[0017] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. The ESP32 module is connected to the AGV master controller via CAN bus. Before executing the start-up and shutdown command, the ESP32 module communicates with the AGV master controller via CAN bus to confirm the status. Status confirmation communication specifically includes: When the ESP32 module receives a remote shutdown command from the scheduling system, it first sends a shutdown request frame to the AGV master controller via the CAN bus. This frame contains a shutdown command identifier and a shutdown countdown parameter. Upon receiving the shutdown request frame, the AGV master controller performs pre-shutdown operations based on the current AGV operating status. These pre-shutdown operations include at least: pausing the currently executing task, resetting the actuator to a safe position, saving non-volatile system parameters, and closing the application process. After completing the pre-shutdown operations, the AGV master controller returns a shutdown confirmation frame to the ESP32 module via the CAN bus. Only after receiving the shutdown confirmation frame does the ESP32 module activate the coil of the normally closed relay K, causing its normally closed contacts to open, thus performing the remote shutdown operation. When the ESP32 module receives a remote power-on command from the scheduling system, it first sends a power-on request frame to the AGV master controller via the CAN bus. After receiving the power-on request frame, the AGV master controller performs a system self-test and returns the self-test status to the ESP32 module via the CAN bus. The ESP32 module only releases the coil of the normally closed relay K and restores its normally closed contacts to close after receiving a confirmation frame confirming that the self-test is normal, thus performing the remote power-on operation.

[0018] According to the present invention, an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 is provided. After the ESP32 module sends a request frame to the AGV master controller via the CAN bus, it starts a timeout countdown. If no confirmation frame is received from the AGV master controller within the preset timeout period, the ESP32 module determines that the AGV master controller communication is abnormal, reports a communication fault alarm to the scheduling system, and maintains the current start-up and shutdown state unchanged, refusing to execute the start-up and shutdown command. The ESP32 module and the AGV master controller establish a periodic heartbeat detection mechanism through the CAN bus. The ESP32 module sends heartbeat frames to the AGV master controller at fixed time intervals to monitor the communication status of the CAN bus and the operating status of the AGV master controller. When the number of consecutive times no heartbeat response frames are received exceeds a preset threshold, the ESP32 module determines that the AGV master controller is offline or faulty, and actively reports a communication fault alarm to the scheduling system, while keeping the current state of the normally closed relay K unchanged.

[0019] A method for dual-mode remote start-up and shutdown control of AGV based on ESP32, which is applied to the aforementioned dual-mode remote start-up and shutdown control circuit of AGV based on ESP32, includes the following steps: Step S1: Manually rotate the manual rotary switch SA to ON. The normally closed relay K remains normally closed. The coil of the AGV main contactor KM is energized, and the AGV is powered on. The auxiliary normally open contact of the AGV main contactor KM closes to form a self-locking circuit, and the AGV continues to run. After the ESP32 module is powered on, it reads the actual power status of the AGV as ON and synchronously sets the desired relay status to ON. In step S2, after receiving the shutdown command from the scheduling system, the ESP32 module sets the desired relay state to OFF, drives the coil of the normally closed relay K to open the normally closed contact, de-energizes the coil of the AGV main contactor KM, de-energizes the AGV, and releases the self-locking; after the ESP32 module reads that the actual power status of the AGV has changed to OFF, it confirms that the shutdown is successful and enters the low-power standby mode. In step S3, after receiving the power-on command from the scheduling system, the ESP32 module is awakened, sets the desired relay state to ON, and drives the coil of the normally closed relay K to restore the normally closed contact to closed. If the manual rotary switch SA is ON, the coil of the AGV main contactor KM is energized, the AGV is powered on, and self-locking is established. If the manual rotary switch SA is OFF, the AGV fails to power on, and the ESP32 module reports an anomaly to the scheduling system. Step S4: If the ESP32 module malfunctions and causes the normally closed relay K to be in the open state, manually rotate the manual rotary switch SA to OFF and then to ON. The ESP32 module will detect that the actual power supply status of the AGV is OFF while the expected relay status is ON, and immediately restore the normally closed relay K to the closed state, so that the AGV returns to normal.

[0020] According to the present invention, a dual-mode remote power-on / off control method for AGV based on ESP32 is provided. The low-power standby mode is the Wi-Fi wake-up sleep mode of ESP32. The specific conditions for the ESP32 module to enter the Wi-Fi wake-up sleep mode are as follows: after the ESP32 module confirms that the actual power state of the AGV is OFF by collecting the auxiliary contact status of the AGV main contactor KM, and the ESP32 module has sent the successful shutdown response back to the scheduling system, the ESP32 module executes the operation of entering the sleep mode. After the ESP32 module enters the Wi-Fi wake-up sleep mode, the internal configuration of the ESP32 module is as follows: the CPU clock is turned off, all peripheral clocks except the Wi-Fi MAC layer are turned off, the Wi-Fi RF transmission link is turned off, the Bluetooth module is turned off, the CAN controller and CAN transceiver are turned off, the GPIO level toggle interrupt function is turned off, and the ADC sampling function is turned off. Only the minimum working circuit of the Wi-Fi receiving link is kept in the listening state to continuously monitor the Media Access Control layer wake-up data packets sent by the scheduling system. The media access control layer wake-up packet contains the unique MAC address or multicast address of the target ESP32 module. The ESP32 module only triggers a wake-up interrupt to restore it from Wi-Fi wake-up sleep mode to full-speed operation mode when the address information in the received wake-up packet matches its own pre-stored address. For Wi-Fi signals with non-matching addresses, the ESP32 module does not respond or wake up and is directly discarded by the minimum working circuit of the Wi-Fi receiving link to minimize the number of invalid wake-ups and power consumption of the ESP32 module during standby. After the ESP32 module is woken up from the Wi-Fi wake-up sleep mode, it first obtains the actual power status of the AGV by collecting the auxiliary contact status of the AGV main contactor KM. The actual power status is then compared and verified with the expected relay status stored inside the ESP32 module. If the two are consistent, the received scheduling command is executed directly. If the two are inconsistent, the state synchronization logic is executed first to match the state of the normally closed relay K with the expected relay status before executing the received scheduling command, ensuring the consistency of the state after wake-up and recovery.

[0021] Therefore, compared with the prior art, the ESP32-based dual-mode remote start-up and shutdown control circuit and method for AGV proposed in this invention have the following beneficial effects: 1. This invention enables one-click start-up or one-click shutdown of hundreds of AGVs through a scheduling system, avoiding the tedious process of manual operation of each AGV, significantly reducing labor and time costs, and greatly improving start-up and shutdown efficiency.

[0022] 2. The manual rotary switch SA, connected in series in the main circuit, has the highest priority for physical disconnection. Even if the remote module crashes or the program malfunctions, on-site personnel can still manually turn the switch SA on and off. More importantly, when a fault in the remote module causes the normally closed relay K to be abnormally open, a simple operation of turning SA to OFF and then ON can trigger the ESP32 module's state synchronization and self-recovery logic, allowing the system to automatically return to normal. This achieves the function of manually resetting the remote module, greatly improving the system's reliability and maintainability.

[0023] 3. This invention utilizes the Wi-Fi wake-up sleep mode of ESP32. After the AGV is turned off, the ESP32 module retains only the minimum working circuit of the Wi-Fi receiving link, reducing the power consumption of the whole machine to less than 10mA. Long-term parking will not cause significant consumption of the AGV battery, avoiding the problem of excessive battery discharge.

[0024] 4. The ESP32 module communicates with the AGV main controller via the CAN bus to confirm the status before shutdown. After receiving the shutdown command, the AGV main controller first pauses the task, saves the data, closes the process, and then performs the power-off operation. This avoids file system corruption, data loss, and hardware failure caused by abnormal power failure of the industrial control computer, and effectively extends the service life of the core components of the AGV.

[0025] 5. This invention only requires connecting a normally closed relay K controlled by ESP32 in series in the coil circuit of the original AGV main contactor KM. There is no need to replace the original switching components or build a complex interlocking circuit. The changes to the original AGV electrical system are minimal, which makes it easy to carry out rapid and low-cost remote start-up and shutdown transformation of a large number of existing AGVs.

[0026] 6. The ESP32 module obtains feedback on the actual power status of the AGV by collecting the status of the KM auxiliary contacts, realizing closed-loop control of remote power on / off operations and ensuring that the execution result of each command can be confirmed. The scheduling system can update the power status of each AGV in real time, forming a global status view, which is convenient for operation and maintenance personnel to monitor and manage.

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0028] Figure 1 This is a system schematic diagram of an embodiment of an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 according to the present invention.

[0029] Figure 2 This is a system architecture diagram of an embodiment of an AGV dual-mode remote start-up and shutdown control method based on ESP32 according to the present invention.

[0030] Figure 3 This is a schematic diagram of the deployment of the AGV remote start-up and start-up group control system in an embodiment of the ESP32-based AGV dual-mode remote start-up and start-up control circuit of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] An embodiment of an AGV dual-mode remote start / stop control circuit based on ESP32 See Figure 1 This embodiment provides an AGV dual-mode remote start-up and shutdown control circuit based on ESP32, including: The original manual rotary switch SA was connected in series in the AGV main circuit to enable manual physical disconnection of the AGV main circuit power supply. The normally closed relay K has its normally closed contacts connected in series between the output terminal of the manual rotary switch SA and the coil of the AGV main contactor KM. The coil is controlled by the ESP32 module to open and close. The AGV main contactor KM has its coil connected in series between the normally closed contact of the normally closed relay K and the power supply circuit. The auxiliary normally open contact of the AGV main contactor KM is connected in parallel with its own coil, forming a self-locking circuit. The self-locking circuit allows the AGV main contactor KM to remain continuously engaged by the brief closing of the manual rotary switch SA or the normally closed relay K. The ESP32 module receives power-on / off commands from the scheduling system via Wi-Fi, controls the coil opening and closing of the normally closed relay K according to the power-on / off commands, and collects the auxiliary contact status of the AGV main contactor KM to confirm the actual power status feedback of the AGV. The power module draws power from the AGV battery and converts it into low-voltage DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The power module draws power from the front end of the AGV main contactor KM, so that the ESP32 module continues to be powered even after the AGV main contactor KM is disconnected.

[0034] In this embodiment, the normally closed relay K remains in a normally closed state when the ESP32 module is not powered on or has not received a shutdown command, ensuring that the AGV main contactor KM can be directly energized and started when the manual rotary switch SA is closed. When the ESP32 module receives a shutdown command, it drives the coil of the normally closed relay K to open its normally closed contacts, cutting off the power supply circuit of the AGV main contactor KM coil and realizing remote shutdown. When the ESP32 module receives a power-on command or recovers from an abnormal state, it releases the coil of the normally closed relay K to close its normally closed contacts again, restoring the control path of the manual rotary switch SA to the AGV main contactor KM.

[0035] In this embodiment, the GPIO port of the ESP32 module is connected to the coil of the normally closed relay K through an optocoupler isolation drive circuit. The optocoupler isolation drive circuit includes an optocoupler and a driving transistor. The input side of the optocoupler is connected to the GPIO port of the ESP32 module through a current-limiting resistor, and the output side of the optocoupler is connected to the control electrode of the driving transistor. The driving transistor is connected in series in the power supply circuit of the normally closed relay K coil. The optocoupler isolation drive circuit is used to achieve electrical isolation between the low-voltage control signal of the ESP32 module and the driving circuit of the normally closed relay K coil, so as to suppress the influence of electromagnetic interference in the AGV high-voltage circuit on the ESP32 module and enhance the driving capability of the GPIO port to the coil of the normally closed relay K.

[0036] In this embodiment, the power module includes a wide-input DC-DC step-down chip. The input terminal of the wide-input DC-DC step-down chip is connected to the output terminal of the AGV battery, and the connection point is located at the front end of the AGV main contactor KM. This ensures that the on / off state of the AGV main contactor KM does not affect the power input of the power module. The output terminal of the wide-input DC-DC step-down chip outputs 3.3V DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The ESP32 module has a built-in Wi-Fi wake-up sleep mode. When the ESP32 module completes the remote shutdown operation and confirms that the AGV's actual power status is off, the ESP32 module immediately enters the Wi-Fi wake-up sleep mode. In sleep mode, the ESP32 module shuts down unnecessary functional modules and peripherals, and only retains the minimum working circuit of the Wi-Fi receiving link to listen for the wake-up command of the scheduling system. The overall power consumption of the ESP32 module in sleep mode is reduced to the microampere level. When the ESP32 module is in sleep mode, the coil of the normally closed relay K is in the de-energized and released state, and its normally closed contact remains closed. At this time, if the manual rotary switch SA is manually turned to ON, the coil of the AGV main contactor KM is energized by the normally closed contact of the normally closed relay K, and the AGV is powered on and started normally. This ensures that manual power-on and power-off operations still have the highest priority and are completely unaffected when the ESP32 module is in low-power sleep mode.

[0037] A pair of normally open auxiliary contacts of the AGV main contactor KM are connected to the GPIO port of the ESP32 module to provide feedback on the actual power status of the AGV to the ESP32 module. The ESP32 module has a built-in status synchronization verification logic, which compares the expected relay status recorded inside the ESP32 module with the actual power status of the AGV collected through the auxiliary normally open contact in real time. When the expected relay status is inconsistent with the actual power status of the AGV, the ESP32 module determines that there is an abnormal status and performs a status self-recovery operation.

[0038] When the expected relay is ON but the actual power supply status of the AGV is OFF, it indicates that the normally closed relay K is actually open due to an abnormal reason. The ESP32 module immediately re-drives the coil of the normally closed relay K to restore its normally closed contacts to close, thereby eliminating the state deviation and realizing system self-recovery. When the expected relay is OFF but the actual power supply status of the AGV is ON, it indicates that the AGV main contactor KM has not disconnected normally due to an abnormal reason. The ESP32 module reports an alarm message to the dispatching system. The status acquisition of the auxiliary normally open contact is also used to confirm the execution result of remote power on / off operations. The ESP32 module only returns a successful operation response after confirming that the actual power status of the AGV is consistent with the target status through the auxiliary normally open contact, thus forming a closed-loop control.

[0039] In this embodiment, the ESP32 module is connected to the AGV master controller via the CAN bus. Before executing the power on / off command, the ESP32 module communicates with the AGV master controller via the CAN bus to confirm its status. Status confirmation communication specifically includes: When the ESP32 module receives a remote shutdown command from the scheduling system, it first sends a shutdown request frame to the AGV master controller via the CAN bus. This frame contains a shutdown command identifier and a shutdown countdown parameter. Upon receiving the shutdown request frame, the AGV master controller performs pre-shutdown operations based on the current AGV operating status. These pre-shutdown operations include at least: pausing the currently executing task, resetting the actuator to a safe position, saving non-volatile system parameters, and closing the application process. After completing the pre-shutdown operations, the AGV master controller returns a shutdown confirmation frame to the ESP32 module via the CAN bus. Only after receiving the shutdown confirmation frame does the ESP32 module activate the coil of the normally closed relay K, causing its normally closed contacts to open, thus performing the remote shutdown operation. When the ESP32 module receives a remote power-on command from the scheduling system, it first sends a power-on request frame to the AGV master controller via the CAN bus. After receiving the power-on request frame, the AGV master controller performs a system self-test and returns the self-test status to the ESP32 module via the CAN bus. The ESP32 module only releases the coil of the normally closed relay K and restores its normally closed contacts to close after receiving a confirmation frame confirming that the self-test is normal, thus performing the remote power-on operation. In this embodiment, after the ESP32 module sends a request frame to the AGV master controller via the CAN bus, it starts a timeout countdown. If no confirmation frame is received from the AGV master controller within the preset timeout period, the ESP32 module determines that the AGV master controller communication is abnormal, reports a communication fault alarm to the scheduling system, and maintains the current power-on / off state unchanged, refusing to execute the power-on / off command. This is to prevent the AGV master controller from being abnormally powered off or powered on before it has completed the state preparation, thus ensuring the data integrity and hardware security of the AGV system.

[0040] The ESP32 module and the AGV master controller establish a periodic heartbeat detection mechanism through the CAN bus. The ESP32 module sends heartbeat frames to the AGV master controller at fixed time intervals to monitor the communication status of the CAN bus and the operating status of the AGV master controller. When the number of consecutive times no heartbeat response frames are received exceeds a preset threshold, the ESP32 module determines that the AGV master controller is offline or faulty, and actively reports a communication fault alarm to the scheduling system, while keeping the current state of the normally closed relay K unchanged.

[0041] In practical applications, the AGV dual-mode remote start-up and shutdown control circuit based on ESP32 of this invention mainly includes: the original manual rotary switch SA, the newly added normally closed relay K, the AGV main contactor KM, the ESP32 module, and the power supply module.

[0042] The manual rotary switch SA is connected in series in the AGV's main circuit. It is the original mechanical rotary switch of the AGV and has two positions: ON and OFF. When SA is turned to OFF, the main circuit is physically cut off, and the AGV is powered off; when SA is turned to ON, the main circuit is connected. This switch has the highest priority, and no remote control can exceed its physical disconnection capability.

[0043] The normally closed relay K is a newly added core component of this invention. Its normally closed contact is connected in series between the output terminal of SA and the input terminal of the KM coil. The coil of K is controlled by the ESP32 module through the GPIO port. When the ESP32 outputs a control signal to drive the coil of K to be energized, the normally closed contact of K opens; when the coil of K is de-energized, the normally closed contact of K closes again.

[0044] The normally closed contact of K and SA form a series dual control node. In this series structure, SA has the highest priority for physically cutting off the main circuit. As long as SA is in the OFF state, the KM coil cannot be energized regardless of the state of K. K is controlled by remote commands and can achieve remote on / off control when SA is ON, ensuring the absolute priority of manual operation.

[0045] The AGV main contactor KM is the original main power contactor of the AGV. Its coil is connected in series between the normally closed contact of K and the negative terminal of the power supply. KM has multiple sets of contacts, including main contacts for switching the main circuit power supply on and off and auxiliary contacts for control logic. Among them, a pair of auxiliary normally open contacts of KM are connected in parallel with KM's own coil to form a self-locking circuit. The working principle of the self-locking circuit is as follows: when the KM coil is energized and KM is attracted, its auxiliary normally open contacts close synchronously, thereby forming a holding path in parallel with the original power supply path at both ends of the KM coil. At this time, even if the contacts of SA or K are briefly opened and closed (for example, contact jitter when the operator rotates the switch), the KM coil can still be continuously energized through the self-locking circuit, maintaining the attracted state of KM. This means that the start-up operation does not require continuously pressing or keeping the switch closed; only a momentary conduction from SA or K is needed to complete the start-up.

[0046] The ESP32 module is the core unit for remote control, receiving power on / off commands from the scheduling system via its onboard Wi-Fi module. The ESP32 module's GPIO port is connected to the coil of device K via an optocoupler-isolated driver circuit, controlling the coil's on / off state according to the received commands. Simultaneously, a pair of normally open auxiliary contacts of device KM are connected to the ESP32 module's GPIO port. The ESP32 module reads the voltage level of this GPIO port to acquire the engagement state of KM, thereby obtaining the AGV's actual power status (ON indicates power on, OFF indicates power off), forming a closed-loop control system.

[0047] The optocoupler-isolated drive circuit consists of an optocoupler and a driver transistor. The input side of the optocoupler is connected to the GPIO port of the ESP32 module via a current-limiting resistor, and the output side is connected to the control electrode (base) of the driver transistor, which is connected in series in the power supply circuit of coil K. When the GPIO port of the ESP32 outputs a high level, the optocoupler conducts, the driver transistor is saturated and conducts, the coil of K is energized, and the normally closed contact opens. When the GPIO port outputs a low level, the optocoupler is cut off, the driver transistor is cut off, the coil of K is de-energized, and the normally closed contact closes again. The optocoupler-isolated drive circuit achieves complete electrical isolation between the low-voltage control signal of the ESP32 module and the drive circuit of the K coil, effectively suppressing the influence of electromagnetic interference in the AGV's high-voltage circuit on the ESP32 module, while also enhancing the driving capability of the GPIO port for the relay coil.

[0048] The power module includes a wide-input DC-DC step-down chip, whose input is connected to the output of the AGV battery. The connection point is located before the KM (i.e., on the battery side, not the load side of the KM), ensuring that the on / off state of the KM does not affect the power module's input power. Whether the KM is engaged or disengaged, the power module can obtain power from the battery. The wide-input DC-DC step-down chip converts the AGV battery voltage (typically 24V, 48V, or 72V, etc.) to 3.3V DC, powering the ESP32 module and the drive circuit of the KM. Because the power point is located before the KM, the ESP32 module can still maintain power supply even when the AGV main contactor KM is disconnected, ensuring the remote control module remains usable when the AGV is powered off.

[0049] An embodiment of a dual-mode remote start-up and shutdown control method for AGVs based on ESP32 like Figure 2 As shown, this embodiment implements the dual-mode power on / off control logic through the software state machine built into the ESP32 module. The state machine involves two core state variables: relay_state: The expected relay state recorded internally by the ESP32 (ON = closed, OFF = open); actual_power: The actual power status of the AGV collected through the KM auxiliary contact (ON=power on, OFF=power off).

[0050] Specifically, this embodiment provides a dual-mode remote start-up and shutdown control method for AGVs based on ESP32. This method is applied to the aforementioned dual-mode remote start-up and shutdown control circuit for AGVs based on ESP32, and includes the following steps: Step S1: Manually rotate the manual rotary switch SA to ON. The normally closed relay K remains normally closed, the coil of the AGV main contactor KM is energized, the AGV is powered on, and the auxiliary normally open contact of the AGV main contactor KM closes to form a self-locking circuit, allowing the AGV to run continuously. After the ESP32 module is powered on, it reads the actual power state of the AGV as ON and synchronously sets the desired relay state to ON. Specifically, after the ESP32 module is initialized upon power-on, it first reads the state of the KM auxiliary contact through GPIO to obtain that actual_power is ON; then it sets relay_state to ON to keep the internally recorded desired state synchronized with the actual state.

[0051] In step S2, after receiving the shutdown command from the scheduling system, the ESP32 module sets the desired relay state to OFF, drives the coil of the normally closed relay K to open the normally closed contact, de-energizes the coil of the AGV main contactor KM, de-energizes the AGV, and releases the self-locking; after the ESP32 module reads that the actual power status of the AGV has changed to OFF, it confirms that the shutdown is successful and enters the low-power standby mode. In step S3, after receiving the power-on command from the scheduling system, the ESP32 module is awakened, sets the desired relay state to ON, and drives the coil of the normally closed relay K to restore the normally closed contact to closed. If the manual rotary switch SA is ON, the coil of the AGV main contactor KM is energized, the AGV is powered on, and self-locking is established. If the manual rotary switch SA is OFF, the AGV fails to power on, and the ESP32 module reports an anomaly to the scheduling system. Step S4: If the ESP32 module malfunctions and causes the normally closed relay K to be in the open state, manually rotate the manual rotary switch SA to OFF and then to ON. The ESP32 module will detect that the actual power supply status of the AGV is OFF while the expected relay status is ON, and immediately restore the normally closed relay K to the closed state, so that the AGV returns to normal.

[0052] In step S2, when the ESP32 module receives the remote shutdown command from the scheduling system via Wi-Fi, it does not immediately perform a power-off operation. The ESP32 module first sends a shutdown request frame to the AGV master controller via the CAN bus. This frame contains a shutdown command identifier and shutdown countdown parameters. After receiving the shutdown request frame, the AGV master controller performs pre-shutdown operations based on the current AGV operating status, including but not limited to: pausing the currently executing task, resetting actuators (such as lifting forks, conveyor rollers, etc.) to a safe position, saving non-volatile system parameters, and closing application processes. After completing the pre-shutdown operations, the AGV master controller returns a shutdown confirmation frame to the ESP32 module via the CAN bus.

[0053] After sending a shutdown request frame, the ESP32 module starts a timeout timer. If no confirmation frame is received from the AGV master controller within the preset timeout period (e.g., 5 seconds), it determines that the AGV master controller communication is abnormal, reports a communication fault alarm to the scheduling system, and maintains the current power-on / off state, refusing to execute the shutdown command to avoid the AGV master controller being abnormally powered off before completing the state preparation.

[0054] The ESP32 module only performs a remote shutdown operation after receiving a shutdown confirmation frame: it sets relay_state to OFF, energizes the coil of K via GPIO and the optocoupler-isolated drive circuit, opens the normally closed contact of K, de-energizes the KM coil, releases KM, de-energizes the AGV main circuit, and releases the self-locking circuit. The ESP32 module reads the status of the KM auxiliary contact via GPIO, and after confirming that actual_power has become OFF, it returns a shutdown success response to the scheduling system.

[0055] In step S2, the low-power standby mode is the Wi-Fi wake-up sleep mode of ESP32; the specific conditions for ESP32 module to enter Wi-Fi wake-up sleep mode are: after ESP32 module confirms that the actual power state of AGV is OFF by collecting the auxiliary contact status of AGV main contactor KM, and ESP32 module has sent the shutdown success response back to the scheduling system, ESP32 module executes the operation of entering sleep mode. After the ESP32 module enters the Wi-Fi wake-up sleep mode, the internal configuration of the ESP32 module is as follows: the CPU clock is turned off, all peripheral clocks except the Wi-Fi MAC layer are turned off, the Wi-Fi RF transmission link is turned off, the Bluetooth module is turned off, the CAN controller and CAN transceiver are turned off, the GPIO level toggle interrupt function is turned off, and the ADC sampling function is turned off. Only the minimum working circuit of the Wi-Fi receiving link is kept in the listening state to continuously monitor the Media Access Control layer wake-up data packets sent by the scheduling system. The media access control layer wake-up packet contains the unique MAC address or multicast address of the target ESP32 module. The ESP32 module only triggers a wake-up interrupt to restore it from Wi-Fi wake-up sleep mode to full-speed operation mode when the address information in the received wake-up packet matches its own pre-stored address. For Wi-Fi signals with non-matching addresses, the ESP32 module does not respond or wake up and is directly discarded by the minimum working circuit of the Wi-Fi receiving link to minimize the number of invalid wake-ups and power consumption of the ESP32 module during standby. The ESP32 module's power consumption in Wi-Fi wake-up sleep mode is reduced to less than 10mA, making the power consumption of the AGV's battery negligible during long-term shutdown. After the ESP32 module is woken up from the Wi-Fi wake-up sleep mode, it first obtains the actual power status of the AGV by collecting the auxiliary contact status of the AGV main contactor KM. The actual power status is then compared and verified with the expected relay status stored inside the ESP32 module. If the two are consistent, the received scheduling command is executed directly. If the two are inconsistent, the state synchronization logic is executed first to match the state of the normally closed relay K with the expected relay status before executing the received scheduling command, ensuring the consistency of the state after wake-up and recovery.

[0056] In step S3, after the scheduling system sends the power-on command, the ESP32 module is woken up from the Wi-Fi wake-up sleep mode. After waking up, the ESP32 module first obtains the actual power status of the AGV by collecting the status of the KM auxiliary contacts, and compares and verifies it with the expected relay status stored internally.

[0057] The ESP32 module then sends a power-on request frame to the AGV master controller via the CAN bus. Upon receiving the power-on request frame, the AGV master controller performs a system self-test and returns the self-test status to the ESP32 module via the CAN bus. The ESP32 module only performs a remote power-on operation after receiving a confirmation frame confirming that the self-test is normal: setting relay_state to ON and releasing the coil of K to restore its normally closed contact to closure.

[0058] There are two possible scenarios at this point: Scenario 1: SA is still ON (normally, SA is not manually operated after remote shutdown). In this case, the KM coil is energized through the closed contacts of SA and K, KM is attracted, the AGV is powered on, self-locking is established, and the startup is successful.

[0059] Scenario 2: SA is OFF (e.g., SA was manually turned OFF after remote shutdown). Even if K is restored to closure, the KM coil will still not be energized, and the AGV will fail to power on. The ESP32 module detects through the KM auxiliary contact that actual_power is still OFF, which does not match the expected ON state. It determines that the startup has failed and reports a "SA not closed" alarm to the scheduling system, prompting maintenance personnel to turn SA to ON on-site.

[0060] In step S4, if the ESP32 module experiences an abnormality such as a crash or program malfunction causing K to be in an abnormally disconnected state (i.e., relay_state is ON but the actual K contact is open), the AGV cannot be remotely powered on. On-site personnel can manually restore the system: rotate SA to OFF to physically disconnect the main circuit; then rotate SA to ON. During this process, the ESP32 module will maintain power supply due to the ON operation of SA (or be woken from sleep mode). Subsequently, the KM auxiliary contact detects that actual_power is OFF (because K is abnormally disconnected, KM cannot be energized), while the internally recorded relay_state is ON, showing a discrepancy. Upon detecting this discrepancy, the ESP32 module's state synchronization verification logic immediately performs a state self-recovery operation—re-driving the K coil to release, causing the normally closed contact of K to close again. Subsequently, the KM coil is energized via SA and K, and the AGV starts normally. Therefore, this embodiment can reset an abnormal remote module to a normal working state through the simplest manual rotary switch operation, without the need for professional technicians or disassembly for repair, greatly improving the system's maintainability and on-site emergency handling capabilities.

[0061] Conversely, if the ESP32 module detects that relay_state is OFF and actual_power is ON (indicating that KM has not disconnected properly due to abnormal reasons), it will report an alarm message to the scheduling system, indicating that the remote shutdown failed, thus ensuring that the fault is traceable.

[0062] like Figure 3 As shown, this embodiment also provides an AGV remote start-up and shutdown group control system. The system includes a scheduling system and multiple AGVs, each AGV being equipped with the aforementioned ESP32-based dual-mode remote start-up and shutdown control circuit.

[0063] Each AGV's ESP32 module is configured with a unique identifier (such as a unique MAC address or a custom ID) to facilitate single-point or group control by the scheduling system. The scheduling system provides a visual operation interface that supports "one-click start" and "one-click end" operations.

[0064] When an operator performs a group control power-on or power-off operation, the scheduling system sends control commands to the target AGV group via Wi-Fi broadcast. For power-off operations, the command can include a power-off countdown parameter, ensuring that all AGVs complete power-off within a unified time window, thus avoiding the impact of instantaneous high current surges on the power supply system.

[0065] After each AGV performs a remote power-on / off operation, it collects the status of the KM auxiliary contact via ESP32 to confirm the actual power status of the AGV and sends the status information (including AGV ID, current power status, operation timestamp, etc.) back to the scheduling system. The scheduling system updates the power status of each AGV in real time based on the status information sent back by each AGV, forming a global status view for easy monitoring by maintenance personnel.

[0066] If an AGV fails to start remotely due to an open SA switch, its ESP32 module will report an "SA not closed" alarm to the dispatch system. The dispatch system will then prompt maintenance personnel to handle the issue on-site via a visual interface. Similarly, if an AGV fails to shut down remotely, the system will report the anomaly, ensuring that the fault is traceable.

[0067] In addition, the ESP32 module and the AGV master controller establish a periodic heartbeat detection mechanism via the CAN bus. The ESP32 module sends heartbeat frames to the AGV master controller at fixed time intervals (e.g., 1 second) to monitor the communication status of the CAN bus and the operating status of the AGV master controller. When the number of consecutive heartbeat response frames not received exceeds a preset threshold (e.g., 3 times), the ESP32 module determines that the AGV master controller is offline or faulty, and proactively reports a communication fault alarm to the scheduling system. At the same time, it keeps the current state of K unchanged to avoid performing potentially dangerous start-up and shutdown operations when the AGV master controller is abnormal.

[0068] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A dual-mode remote start / stop control circuit for AGV based on ESP32, characterized in that, include: The original manual rotary switch SA was connected in series in the AGV main circuit to enable manual physical disconnection of the AGV main circuit power supply. The normally closed relay K has its normally closed contacts connected in series between the output terminal of the manual rotary switch SA and the coil of the AGV main contactor KM. The coil is controlled by the ESP32 module to open and close. The AGV main contactor KM has its coil connected in series between the normally closed contact of the normally closed relay K and the power supply circuit. The auxiliary normally open contact of the AGV main contactor KM is connected in parallel with its own coil, forming a self-locking circuit. The self-locking circuit allows the AGV main contactor KM to remain continuously engaged by the brief closing of the manual rotary switch SA or the normally closed relay K. The ESP32 module receives power-on / off commands from the scheduling system via Wi-Fi, controls the coil opening and closing of the normally closed relay K according to the power-on / off commands, and collects the auxiliary contact status of the AGV main contactor KM to confirm the actual power status feedback of the AGV. The power module draws power from the AGV battery and converts it into low-voltage DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The power module draws power from the front end of the AGV main contactor KM, so that the ESP32 module continues to be powered even after the AGV main contactor KM is disconnected.

2. The circuit according to claim 1, characterized in that: Normally closed relay K remains in a normally closed state when the ESP32 module is not powered on or has not received a shutdown command, ensuring that the AGV main contactor KM can be directly energized and started when the manual rotary switch SA is closed. When the ESP32 module receives a shutdown command, it drives the coil of normally closed relay K to open its normally closed contacts, cutting off the power supply circuit of the AGV main contactor KM coil and realizing remote shutdown. When the ESP32 module receives a power-on command or recovers from an abnormal state, it releases the coil of normally closed relay K to close its normally closed contacts again, restoring the control path of the manual rotary switch SA to the AGV main contactor KM.

3. The circuit according to claim 1, characterized in that: The GPIO port of the ESP32 module is connected to the coil of the normally closed relay K through an optocoupler isolation drive circuit. The optocoupler isolation drive circuit includes an optocoupler and a driver transistor. The input side of the optocoupler is connected to the GPIO port of the ESP32 module through a current-limiting resistor, and the output side of the optocoupler is connected to the control electrode of the driver transistor. The driver transistor is connected in series in the power supply circuit of the normally closed relay K coil. The optocoupler isolation drive circuit is used to achieve electrical isolation between the low-voltage control signal of the ESP32 module and the drive circuit of the normally closed relay K coil, so as to suppress the influence of electromagnetic interference in the AGV high-voltage circuit on the ESP32 module and enhance the driving capability of the GPIO port to the coil of the normally closed relay K.

4. The circuit according to claim 1, characterized in that: The power module includes a wide-input DC-DC step-down chip. The input terminal of the wide-input DC-DC step-down chip is connected to the output terminal of the AGV battery, and the connection point is located at the front end of the AGV main contactor KM. The output terminal of the wide-input DC-DC step-down chip outputs 3.3V DC power to power the drive circuit of the ESP32 module and the normally closed relay K. The ESP32 module has a built-in Wi-Fi wake-up sleep mode. When the ESP32 module completes the remote shutdown operation and confirms that the actual power status of the AGV is off, the ESP32 module immediately enters the Wi-Fi wake-up sleep mode. In sleep mode, the ESP32 module shuts down unnecessary functional modules and peripherals, and only retains the minimum working circuit of the Wi-Fi receiving link to listen for the wake-up command of the scheduling system. When the ESP32 module is in sleep mode, the coil of the normally closed relay K is in the de-energized and released state, and its normally closed contact remains closed. At this time, if the manual rotary switch SA is manually turned to ON, the coil of the AGV main contactor KM is energized by the normally closed contact of the normally closed relay K, and the AGV is powered on and started normally.

5. The circuit according to claim 1, characterized in that: A pair of normally open auxiliary contacts of the AGV main contactor KM are connected to the GPIO port of the ESP32 module to provide feedback on the actual power status of the AGV to the ESP32 module. The ESP32 module has a built-in status synchronization verification logic, which compares the expected relay status recorded inside the ESP32 module with the actual power status of the AGV collected through the auxiliary normally open contact in real time. When the expected relay status is inconsistent with the actual power status of the AGV, the ESP32 module determines that there is an abnormal status and performs a status self-recovery operation.

6. The circuit according to claim 5, characterized in that: When the expected relay is ON but the actual power supply status of the AGV is OFF, it indicates that the normally closed relay K is actually open due to an abnormal reason. The ESP32 module immediately re-drives the coil of the normally closed relay K to restore its normally closed contacts to close, thereby eliminating the state deviation and realizing system self-recovery. When the expected relay is OFF but the actual power supply status of the AGV is ON, it indicates that the AGV main contactor KM has not disconnected normally due to an abnormal reason. The ESP32 module reports an alarm message to the dispatching system. The status acquisition of the auxiliary normally open contact is also used to confirm the execution result of remote power on / off operations. The ESP32 module only returns a successful operation response after confirming that the actual power status of the AGV is consistent with the target status through the auxiliary normally open contact, thus forming a closed-loop control.

7. The circuit according to claim 1, characterized in that: The ESP32 module connects to the AGV main controller via the CAN bus. Before executing the power on / off command, the ESP32 module communicates with the AGV main controller via the CAN bus to confirm its status. Status confirmation communication specifically includes: When the ESP32 module receives a remote shutdown command from the scheduling system, it first sends a shutdown request frame to the AGV master controller via the CAN bus. This frame contains a shutdown command identifier and a shutdown countdown parameter. Upon receiving the shutdown request frame, the AGV master controller performs pre-shutdown operations based on the current AGV operating status. These pre-shutdown operations include at least: pausing the currently executing task, resetting the actuator to a safe position, saving non-volatile system parameters, and closing the application process. After completing the pre-shutdown operations, the AGV master controller returns a shutdown confirmation frame to the ESP32 module via the CAN bus. Only after receiving the shutdown confirmation frame does the ESP32 module activate the coil of the normally closed relay K, causing its normally closed contacts to open, thus performing the remote shutdown operation. When the ESP32 module receives a remote power-on command from the scheduling system, it first sends a power-on request frame to the AGV master controller via the CAN bus. After receiving the power-on request frame, the AGV master controller performs a system self-test and returns the self-test status to the ESP32 module via the CAN bus. The ESP32 module only releases the coil of the normally closed relay K and restores its normally closed contacts to close after receiving a confirmation frame confirming that the self-test is normal, thus performing the remote power-on operation.

8. The circuit according to claim 7, characterized in that: After sending a request frame to the AGV master controller via the CAN bus, the ESP32 module starts a timeout countdown. If no acknowledgment frame is received from the AGV master controller within the preset timeout period, the ESP32 module determines that the AGV master controller communication is abnormal, reports a communication fault alarm to the scheduling system, and maintains the current power-on / off state, refusing to execute this power-on / off command. The ESP32 module and the AGV master controller establish a periodic heartbeat detection mechanism through the CAN bus. The ESP32 module sends heartbeat frames to the AGV master controller at fixed time intervals to monitor the communication status of the CAN bus and the operating status of the AGV master controller. When the number of consecutive times no heartbeat response frames are received exceeds a preset threshold, the ESP32 module determines that the AGV master controller is offline or faulty, and actively reports a communication fault alarm to the scheduling system, while keeping the current state of the normally closed relay K unchanged.

9. A method for dual-mode remote start / stop control of AGV based on ESP32, characterized in that, This method is applied to an AGV dual-mode remote start-up and shutdown control circuit based on ESP32 as described in any one of claims 1 to 8, and includes the following steps: Step S1: Manually rotate the manual rotary switch SA to ON. The normally closed relay K remains normally closed. The coil of the AGV main contactor KM is energized, and the AGV is powered on. The auxiliary normally open contact of the AGV main contactor KM closes to form a self-locking circuit, and the AGV continues to run. After the ESP32 module is powered on, it reads the actual power status of the AGV as ON and synchronously sets the desired relay status to ON. In step S2, after receiving the shutdown command from the scheduling system, the ESP32 module sets the desired relay state to OFF, drives the coil of the normally closed relay K to open the normally closed contact, de-energizes the coil of the AGV main contactor KM, de-energizes the AGV, and releases the self-locking; after the ESP32 module reads that the actual power status of the AGV has changed to OFF, it confirms that the shutdown is successful and enters the low-power standby mode. In step S3, after receiving the power-on command from the scheduling system, the ESP32 module is awakened, sets the desired relay state to ON, and drives the coil of the normally closed relay K to restore the normally closed contact to closed. If the manual rotary switch SA is ON, the coil of the AGV main contactor KM is energized, the AGV is powered on, and self-locking is established. If the manual rotary switch SA is OFF, the AGV fails to power on, and the ESP32 module reports an anomaly to the scheduling system. Step S4: If the ESP32 module malfunctions and causes the normally closed relay K to be in the open state, manually rotate the manual rotary switch SA to OFF and then to ON. The ESP32 module will detect that the actual power supply status of the AGV is OFF while the expected relay status is ON, and immediately restore the normally closed relay K to the closed state, so that the AGV returns to normal.

10. The method according to claim 9, characterized in that: The low-power standby mode is the Wi-Fi wake-up sleep mode of ESP32. The specific conditions for the ESP32 module to enter the Wi-Fi wake-up sleep mode are: after the ESP32 module confirms that the actual power status of the AGV is OFF by collecting the auxiliary contact status of the AGV main contactor KM, and the ESP32 module has sent the shutdown success response back to the scheduling system, the ESP32 module will execute the operation of entering sleep mode. After the ESP32 module enters the Wi-Fi wake-up sleep mode, the internal configuration of the ESP32 module is as follows: the CPU clock is turned off, all peripheral clocks except the Wi-Fi MAC layer are turned off, the Wi-Fi RF transmission link is turned off, the Bluetooth module is turned off, the CAN controller and CAN transceiver are turned off, the GPIO level toggle interrupt function is turned off, and the ADC sampling function is turned off. Only the minimum working circuit of the Wi-Fi receiving link is kept in the listening state to continuously monitor the Media Access Control layer wake-up data packets sent by the scheduling system. The media access control layer wake-up packet contains the unique MAC address or multicast address of the target ESP32 module. The ESP32 module only triggers a wake-up interrupt to restore it from Wi-Fi wake-up sleep mode to full-speed operation mode when the address information in the received wake-up packet matches its own pre-stored address. For Wi-Fi signals with non-matching addresses, the ESP32 module does not respond or wake up and is directly discarded by the minimum working circuit of the Wi-Fi receiving link to minimize the number of invalid wake-ups and power consumption of the ESP32 module during standby. After the ESP32 module is woken up from the Wi-Fi wake-up sleep mode, it first obtains the actual power status of the AGV by collecting the auxiliary contact status of the AGV main contactor KM. The actual power status is then compared and verified with the expected relay status stored inside the ESP32 module. If the two are consistent, the received scheduling command is executed directly. If the two are inconsistent, the state synchronization logic is executed first to match the state of the normally closed relay K with the expected relay status before executing the received scheduling command, ensuring the consistency of the state after wake-up and recovery.

Images