Library collection intelligent book conveying system based on FPGA (Field Programmable Gate Array)

Abstract

According to the intelligent library collection conveying system based on the FPGA, the FPGA serves as a main control core, a mechanical arm executing mechanism is integrated on the basis of a moving trolley integrating intelligent tracking and intelligent recognition, books are intelligently recognized in combination with image recognition, and book grabbing, taking and conveying are achieved through omnidirectional movement of the moving trolley and cooperative control of a trolley arm; the method is suitable for automatic book distribution in libraries, archives and other scenes. The main control FPGA module is electrically connected with the multi-path infrared tracking module, the mechanical arm executing mechanism, the image recognition module and a driving module of the moving trolley, drives the multi-path infrared tracking module, the mechanical arm executing mechanism, the image recognition module and the driving module of the moving trolley to work and is used for controlling operation of the intelligent book conveying system, and when the image recognition module recognizes books, the moving trolley and the mechanical arm executing mechanism are controlled to move in linkage. The linkage of the movement control of the moving trolley and the grabbing action of the mechanical arm executing mechanism is realized.

Description

Technical Field

[0001] This invention relates to the field of intelligent library management technology, and more particularly to the application of embodied intelligence technology in automated library management, specifically to an FPGA-based intelligent book delivery system for library collections. Background Technology

[0002] The library's collection employs standardized cataloging and classification to ensure a standardized and regulated arrangement, achieving orderliness and easy accessibility. Books are arranged in strict order, typically based on classification numbers, grouping similar documents together for easy retrieval by category. Furthermore, a comprehensive catalog system and online OPAC system have been established through standardized cataloging data. Readers can quickly and accurately find the location and status of desired documents using multiple methods, including title, author, subject, classification number, and ISBN.

[0003] Currently, self-service book retrieval and return systems, such as smart book lockers, self-service borrowing lockers, and self-service book return lockers, have been deployed in libraries and communities. These systems, operating unattended, not only facilitate convenient borrowing and / or returning of books but also significantly expand the reach and service radius of traditional libraries. However, regardless of whether these self-service systems are deployed inside or outside the library, when books are returned and need to be shelved, manual retrieval and delivery are still required, even with the traditional reliance on librarians manually verifying the book numbering system and the availability of RFID technology for rapid identification and inventory. Summary of the Invention

[0004] The purpose of this invention is to provide an intelligent book delivery system for libraries based on FPGA. The system uses FPGA as the main control core and integrates a robotic arm actuator on the basis of a mobile car that integrates intelligent tracking and intelligent recognition. It combines image recognition to intelligently identify books and realizes book grabbing and delivery through omnidirectional movement of the mobile car and coordinated control of the car arm. It is suitable for automated book delivery in scenarios such as libraries and archives.

[0005] According to a first aspect of the present invention, an FPGA-based intelligent book delivery system for library collections is proposed, comprising: A mobile trolley driven by a stepper motor, the mobile trolley is equipped with two pairs of symmetrically distributed omnidirectional wheels, and the omnidirectional wheels are driven to move by the rotation output of the stepper motor; A multi-channel infrared tracking module, integrated on a mobile vehicle, consists of an infrared sensor and a comparison circuit, and is used for ground path recognition and yaw correction. The robotic arm actuator, integrated on the mobile vehicle, includes a multi-degree-of-freedom robotic arm and an actuator gripper at the end of the robotic arm, used for book grabbing and dropping; An image recognition module, mounted on a mobile vehicle, is used to identify and locate the presence of books; The main control FPGA module is electrically connected to and drives the multi-channel infrared tracking module, the robotic arm actuator, the image recognition module, and the drive module of the mobile trolley to control the operation of the intelligent book delivery system. After recognizing a book, it controls the movement of the mobile trolley and the robotic arm actuator to achieve linkage between the motion control of the mobile trolley and the grasping action of the robotic arm actuator.

[0006] As an optional implementation, the omnidirectional wheels of the mobile vehicle are all Mecanum wheels, and each omnidirectional wheel is independently equipped with a stepper motor. The omnidirectional movement of the mobile vehicle is achieved by driving the corresponding Mecanum wheel through the stepper motor.

[0007] As an optional implementation, the multi-channel infrared tracking module includes eight TCRT5000 reflective infrared sensors and an LM393 comparator circuit to achieve automatic tracking and yaw correction, thereby enabling the movement control of the mobile vehicle.

[0008] As an optional implementation, the 8-channel TCRT5000 reflective infrared sensors are arranged in a double-layer layout of top layer + bottom layer, and are symmetrically distributed with 4 channels L1-L4 on the left and 4 channels R1-R4 on the right. The top layer layout of the PCB board of the multi-channel infrared tracking module is YCCGNDL4-L4, R1-R4, and the bottom layer layout is R4-R1, L1-L4. Ground black and white path information is collected by 8-channel TCRT5000 reflective infrared sensors. The 8-channel reflective signals are converted into digital quantities by two-channel LM393 comparators. The digital signals are output to the main control FPGA module for yaw error calculation. The FPGA corrects the path yaw by comparing the difference between the output values ​​of the left and right sensors.

[0009] As an optional implementation, the driving module of the mobile vehicle adopts the TMC229 driving chip.

[0010] As an optional implementation, the mobile vehicle is powered by a supercapacitor power supply module and wirelessly charged by an LLC-based wireless charging system. The supercapacitor power supply module includes four 100F / 2.7V supercapacitors, whose positive and negative terminals are electrically connected to the supercapacitor detection module to detect the voltage value of the wireless charging supercapacitor.

[0011] As an optional implementation, the wireless charging system includes a transmitter and a receiver. The transmitter is deployed inside the library and has two half-bridge drivers and an LCC transmitting resonant circuit for transmitting signals. The receiver is arranged on a mobile vehicle for receiving AC signals, which are then converted into DC power through a rectifier bridge circuit and finally used to charge the supercapacitor power supply module.

[0012] As an optional implementation, the image recognition module uses a PGL22H as the image master control FPGA, combined with an OV5640 camera. The OV5640 camera acquires image data within the field of view, and the PGL22H image master control FPGA performs image processing to locate whether there are books inside the book frame. An indicator light indicates which position has a book. The PGL22H image master control FPGA transmits the recognition results to the master control FPGA module via UART serial port, which is used to trigger the master control FPGA module to control the arm-mounted collaborative movement.

[0013] As an optional implementation, the intelligent book delivery system also includes an ultrasonic obstacle avoidance module electrically connected to the main control FPGA module, which uses an HCSR04 ultrasonic sensor to detect whether there are obstacles in front. The ultrasonic obstacle avoidance module and the multi-channel infrared tracking module form a multi-sensor fusion perception. When an obstacle is detected, the main control FPGA module is set to prioritize triggering the preset obstacle avoidance algorithm and suspend the coordinated movement of the vehicle arm.

[0014] As an optional implementation, the main control FPGA module adopts the Ziguang Tongchuang PGL50H, which, together with the PGL22H image main control FPGA, forms a dual FPGA collaborative architecture to realize real-time and parallel processing of system control and image recognition.

[0015] The above-described embodiment of the present invention provides an FPGA-based intelligent book delivery system for libraries. This system utilizes an intelligent mobile vehicle integrating intelligent tracking and recognition capabilities. A robotic arm actuator is integrated onto the vehicle, enabling book grabbing and delivery through omnidirectional movement of the vehicle and coordinated control of the robotic arm. The FPGA-based intelligent book delivery system employs a Ziguang Tongchuang PGL50H as the main control FPGA and a PGL22H as the image control FPGA, forming a dual-FPGA collaborative architecture. This architecture enables real-time, parallel processing of system control and image recognition, achieving efficient linkage between book recognition, grabbing, and movement. It features rapid response, accurate positioning, and strong scene adaptability, significantly improving the efficiency of library book delivery.

[0016] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below may be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other. Furthermore, all combinations of the claimed subject matter are considered part of the inventive subject matter of this disclosure.

[0017] The foregoing and other aspects, embodiments, and features of the teachings of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the invention, such as features and / or beneficial effects of exemplary embodiments, will become apparent from the following description or may be learned through practice of specific embodiments according to the teachings of the present invention. Attached Figure Description

[0018] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings.

[0019] Figure 1 This is a schematic diagram of the principle of an FPGA-based intelligent book delivery system for libraries according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the principle of a mobile vehicle according to an embodiment of the present invention.

[0021] Figure 3 This is a schematic diagram of the ADC circuit used in the supercapacitor detection module according to an embodiment of the present invention.

[0022] Figure 4 It is based on the present invention Figure 3 The circuit diagram shown is a voltage divider and current limiting protection circuit for voltage T1.

[0023] Figure 5 This is a circuit diagram of the 12V regulated output of a mobile vehicle according to an embodiment of the present invention.

[0024] Figure 6 This is a circuit diagram of the servo motor power output on a mobile vehicle according to an embodiment of the present invention.

[0025] Figure 7 This is a schematic diagram of a 5V regulated power supply circuit for the drive circuit on a mobile vehicle according to an embodiment of the present invention.

[0026] Figure 8A , 8B These are schematic diagrams of the h-bridge drive circuit of the mobile trolley drive circuit according to an embodiment of the present invention.

[0027] Figure 9This is a schematic diagram of the stepper motor encoder circuit of a mobile trolley according to an embodiment of the present invention. Detailed Implementation

[0028] To better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

[0029] Various aspects of the invention are described in this disclosure with reference to the accompanying drawings, which illustrate numerous illustrative embodiments. The embodiments of this disclosure are not necessarily intended to encompass all aspects of the invention. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed herein are not limited to any particular implementation. Furthermore, some aspects of the invention disclosed may be used alone or in any suitable combination with other aspects of the invention disclosed.

[0030] {Example 1} As shown in the accompanying drawings, the FPGA-based intelligent book delivery system for libraries according to an embodiment of the present invention includes a main control FPGA module, a mobile vehicle, an image recognition module, an ultrasonic obstacle avoidance module, a multi-channel infrared tracking module, and a robotic arm execution mechanism.

[0031] The mobile cart serves as the mobile integration platform for the intelligent book delivery system. It integrates an image recognition module, an ultrasonic obstacle avoidance module, a multi-channel infrared tracking module, and a robotic arm actuator. The cart is equipped with two pairs of symmetrically distributed omnidirectional wheels, which are driven by stepper motors. The rotation output of the stepper motors drives the omnidirectional wheels to move.

[0032] As an optional implementation, the omnidirectional wheels of the mobile vehicle are all Mecanum wheels, and each omnidirectional wheel is independently equipped with a stepper motor. The omnidirectional movement of the mobile vehicle is achieved by driving the corresponding Mecanum wheel through the stepper motor.

[0033] As an optional embodiment, the driving module of the mobile vehicle adopts the TMC229 driver chip.

[0034] Combination Figure 1 , Figure 2 The mobile vehicle is powered by a supercapacitor power supply module and wirelessly charged by an LLC-based wireless charging system.

[0035] The supercapacitor power supply module includes four 100F / 2.7V supercapacitors, whose positive and negative terminals are electrically connected to the supercapacitor detection module to detect the voltage value of the wireless charging supercapacitor.

[0036] In an embodiment of the invention, a supercapacitor provides DC power, which is supplied by wireless charging. The DC output from the supercapacitor is stepped down and then fed to the main control FPGA module. The main control FPGA module generates four PWM modulation control signals to control the movement of the stepper motors of the mobile vehicle, driving the corresponding Mecanum wheels to move, thereby realizing the vehicle's tracking and omnidirectional movement.

[0037] As an optional implementation, the wireless charging system includes a transmitter and a receiver. The transmitter is deployed inside the library and has two half-bridge drivers and an LCC transmitting resonant circuit for transmitting signals. The receiver is arranged on a mobile vehicle for receiving AC signals, which are then converted into DC power through a rectifier bridge circuit and finally used to charge the supercapacitor power supply module.

[0038] In an embodiment of the present invention, a multi-channel infrared tracking module is integrated on a mobile vehicle and consists of an infrared sensor and a comparison circuit, used for ground path identification and yaw correction.

[0039] As an optional implementation, the multi-channel infrared tracking module includes eight TCRT5000 reflective infrared sensors and an LM393 comparator circuit to achieve automatic tracking and yaw correction, thereby enabling the movement control of the mobile vehicle.

[0040] As an optional implementation, the 8-channel TCRT5000 reflective infrared sensors are arranged in a double-layer layout of top layer + bottom layer, and are symmetrically distributed with 4 channels L1-L4 on the left and 4 channels R1-R4 on the right. The top layer layout of the PCB board of the multi-channel infrared tracking module is YCCGNDL4-L4, R1-R4, and the bottom layer layout is R4-R1, L1-L4. Ground black and white path information is collected by 8-channel TCRT5000 reflective infrared sensors. The 8-channel reflective signals are converted into digital quantities by two-channel LM393 comparators. The digital signals are output to the main control FPGA module for yaw error calculation. The FPGA corrects the path yaw by comparing the difference between the output values ​​of the left and right sensors.

[0041] The symmetrical design of YCCGNDL4-L4 and R1-R4 on the top layer of the PCB board and R4-R1 and L1-L4 on the bottom layer enhances the anti-interference capability.

[0042] As an optional implementation, the operation of the multi-channel infrared tracking module includes: The left-right sensor array, consisting of 8 TCRT5000 reflective infrared sensors, emits infrared light in real time to detect black and white paths on the ground. Two LM393 comparators convert the reflection intensity into high and low levels (the black path outputs a high level), which are then connected to the main control FPGA module; The main control FPGA module acquires 8 signals through the GPIO interface and calculates the difference in the number of high-level outputs from the left and right sensors. When the difference exceeds the threshold, the PID module adjusts the corresponding wheel speed to achieve steering correction.

[0043] In an embodiment of the present invention, a robotic arm actuator is integrated on a mobile vehicle and includes a multi-degree-of-freedom robotic arm and an actuator gripper disposed at the end of the robotic arm for book grabbing and dropping.

[0044] As an optional embodiment, the multi-degree-of-freedom robotic arm adopts a commercially available multi-segment multi-degree-of-freedom robotic arm, with each joint equipped with a high-precision joint motor (especially a high-precision stepper motor) to achieve multi-degree-of-freedom drive. In this example, a robotic arm with three joint stepper motors is used as an example, with a flexible gripper at the end.

[0045] The end effector gripper of the robotic arm can be a flexible gripper mechanism controlled by commercial servo motors. The gripper grips and releases the books by controlling the gripper's gripping and releasing actions.

[0046] In an embodiment of the present invention, an image recognition module is mounted on a mobile vehicle and is used to identify and locate whether a book exists.

[0047] As an optional implementation, the image recognition module uses a PGL22H as the image master control FPGA, combined with an OV5640 camera. The OV5640 camera acquires image data within the field of view, and the PGL22H image master control FPGA performs image processing to locate whether there are books inside the book frame. An indicator light indicates which position has a book.

[0048] The PGL22H image master control FPGA transmits the recognition results to the master control FPGA module via UART serial port, which is used to trigger the master control FPGA module to control the arm-mounted coordinated movement.

[0049] In an optional embodiment, a pre-set graphics processing algorithm program is burned into the FLASH memory of the image control FPGA. When called and executed, the program performs radial sequential processing on the image acquired by the OV5640 camera. As an example, the process includes: converting the image to grayscale, calculating an automatic threshold using the Otsu method, obtaining a binarized image through threshold segmentation, locating whether there are books inside the book frame through vertical projection analysis, and finally displaying which position has a book through indicator lights.

[0050] In an embodiment of the present invention, a main control FPGA module is electrically connected to and drives a multi-channel infrared tracking module, a robotic arm actuator, an image recognition module, and a drive module of a mobile cart to control the operation of the intelligent book delivery system. After recognizing a book, the main control FPGA module controls the movement of the mobile cart and the robotic arm actuator to achieve linkage between the motion control of the mobile cart and the grasping action of the robotic arm actuator.

[0051] Combination Figure 1 As shown, as an optional implementation, the ultrasonic obstacle avoidance module is electrically connected to the main control FPGA module, and uses an HCSR04 ultrasonic sensor to detect whether there are obstacles in front.

[0052] The ultrasonic obstacle avoidance module and the multi-channel infrared tracking module form a multi-sensor fusion perception. When an obstacle is detected, the main control FPGA module is set to prioritize triggering the preset obstacle avoidance algorithm and suspend the coordinated movement of the arm.

[0053] As an optional implementation, the main control FPGA module adopts the Ziguang Tongchuang PGL50H, which, together with the PGL22H image main control FPGA, forms a dual FPGA collaborative architecture to realize real-time and parallel processing of system control and image recognition.

[0054] like Figure 1 As shown, the intelligent book delivery system is also equipped with a display screen, which is connected to the main control FPGA module via a serial port to provide a human-computer interaction interface and support command issuance and status feedback.

[0055] Therefore, for the movement and walking of the mobile vehicle, the main control FPGA module outputs PWM signals to control the speed and direction of the vehicle's four wheels; for the robotic arm and gripper, the main control FPGA module drives the stepper motors at the joint positions of the robotic arm to achieve joint rotation, and drives the servo motors to achieve the gripper's opening and closing. The main control FPGA module can schedule the execution sequence of the mobile vehicle's movement and the robotic arm's grasping actions based on a finite state machine, ensuring that the robotic arm accurately performs the grasping operation after reaching the target position.

[0056] The ultrasonic obstacle avoidance module and the multi-channel infrared tracking module form a multi-sensor fusion perception. When an obstacle is detected, the main control FPGA module is set to prioritize triggering the preset obstacle avoidance algorithm and suspend the coordinated movement of the arm.

[0057] In an optional embodiment, the main control FPGA module has a built-in PID control algorithm, which can generate the movement trajectory command of the car based on the data from the tracking module and the image recognition module. When the moving car reaches the target position (such as the AC point on the bookshelf), the main control FPGA module sends a trigger signal to the robotic arm control via UART. The robotic arm executes the action according to the preset grasping logic, and at the same time feeds back the status to the FPGA through the limit sensor, pausing the movement of the car. After the grasping is completed, the main control FPGA module restarts the movement command of the car to complete the delivery of books.

[0058] As an example, the process of boom-arm cooperative control is as follows: The user issues a book delivery command through the human-computer interaction module, and the main control FPGA module plans the path. The mobile vehicle travels along the path identified by multiple infrared tracking modules, while simultaneously using an ultrasonic obstacle avoidance module to monitor obstacles in real time and avoid them. Upon reaching the target bookshelf, the image recognition module confirms the book's location, and the main control FPGA module sends a command to start the robotic arm. The robotic arm moves and the gripper is controlled by the servo motor to perform the grasping action. After the grasping is successful, the car starts to move to the delivery point. The robotic arm drops the book, and then the cart returns to its initial position.

[0059] In the embodiments of the present invention, the control logic of the main control FPGA module adopts a modular design using Verilog language, and the motion control and robotic arm control communicate through an internal bus to ensure accurate coordination timing.

[0060] {Example 2} In this embodiment, we will combine Figure 1 , 2 and appendix Figure 3-9 The specific implementation process of the present invention will be described in more detail below.

[0061] like Figure 3 , 4 The supercapacitor's output voltage VIN is connected to a voltage divider circuit, divided 10:1, and then output to the ADC1_IN2 pin (connected to the analog input of the ADC081CIMK / NOPB chip). A 3V3 power supply is connected to the ADC chip's SDA and SCL pins via R2 (pull-up resistor) to achieve I2C bus level matching. The ADC chip's VA is connected to the 3V3 power supply, and GND is connected to system ground, providing power and communication for the ADC chip. Simultaneously, a transient suppression diode T1 is connected in parallel between the divided signal terminal and GND to prevent voltage spikes from damaging the ADC chip; capacitor C2 is connected in parallel between ADC1_IN2 and GND to filter out high-frequency noise in the divided signal.

[0062] exist Figure 4 In China, combined Figure 3 As shown, the input interfaces are: VIN_GND (voltage divider network ground) and VIN (supercapacitor voltage input); the signal output is ADCIN2 (connected to the ADC sampling terminal). VIN is connected to VIN_GND in series with resistors R4 (100KΩ) and R5 (10KΩ). The voltage divider node (the connection point of R4 and R5) serves as the intermediate signal terminal. After current limiting by R6 (4KΩ), the intermediate signal terminal is connected to the ADCIN2 pin to achieve current-limited output. Figure 3 The ADC1_IN2 are connected at a common point to achieve secondary current limiting protection for the voltage divider signal; at the same time, VIN_GND is connected to the system ground (GND) to ensure that the reference potential of the voltage divider network is consistent.

[0063] Therefore, R4 and R5 form a basic voltage divider circuit to achieve a total voltage division ratio of 10:1. Furthermore, resistor R6 limits the current flowing into the ADC chip to prevent overcurrent damage to the ADC input pins. Ultimately, this achieves dual protection of high voltage → low voltage + current limiting, ensuring the safety of the sampling signal.

[0064] Therefore, the high voltage of the supercapacitor is reduced by a voltage divider circuit (to match the input range of the ADC chip). After the ADC chip completes the analog-to-digital conversion, the supercapacitor voltage data is transmitted to the main control FPGA via the I2C bus (SDA / SCL) to realize voltage detection. The main control FPGA module determines whether to trigger wireless charging based on the voltage value.

[0065] Combination Figure 5 The diagram shows the power supply regulator circuit for the car's mainboard. The car is powered by a 24V supercapacitor. Part of the 24V voltage is regulated by a 12V voltage regulator circuit using a TPS54560 chip, while the other part regulates the 24V voltage to 7-9V for output to the servo motors using an SCT2450 chip. Figure 6 This indicates the power supply circuit for the servo motor.

[0066] exist Figure 5 In the design shown, the +24V voltage input provided by the supercapacitor is connected to the VIN pin of the TPS54560 voltage regulator chip (synchronous buck chip, 24V input, 12V output), and systematically connected to the GND pin; the EN pin is connected to a high level (e.g., 3.3V) to put the chip into working state.

[0067] By converting the 24V high voltage output from the supercapacitor into a stable 12V output, the system provides an adapter voltage for peripherals such as the drive module of the mobile vehicle (the H-bridge drive chip in Figure 8) and the infrared tracking module, ensuring that the peripherals work normally.

[0068] exist Figure 6In the design shown, the SCT2450 voltage regulator chip is an adjustable step-down chip with an input of 24V and an output of 7-9V. R15 (30KΩ), R16 (10KΩ), R17 (50KΩ), R18 (200KΩ), R19 (7.5KΩ), and R20 (20KΩ) form a voltage divider regulation network. C10 (4.7μF), C11 (220μF / 25V), C12 (100μF / 50V), C13 (4.7nF), and C14 (100nF) are filter capacitors. Figure 6 The +24V voltage input provided by the supercapacitor is connected to the VIN pin (pin 3) of the SCT2450, and GND is connected to the GND pin (pin 0) of the chip. The SW pin of the chip is connected to one end of the inductor L and the anode of D3 (freewheeling diode), and the other end of the inductor is connected to the servo power output terminal; the cathode of D3 is connected to GND to prevent the inductor reverse current from impacting the chip, thus realizing voltage reduction and energy transfer; the FB pin of the chip is connected to a voltage divider network composed of R18 (200KΩ), R19 (7.5KΩ), and R20 (20KΩ). By adjusting the resistance ratio of R19 and R20, the 7-9V output voltage can be adjusted to meet the power supply requirements of the servo. The SCT2450 provides a 24V voltage reduction to meet the voltage requirements of the servo. The filter circuit ensures smooth servo operation and avoids voltage fluctuations affecting the gripper's grasping accuracy, providing a stable and adjustable 7-9V power supply for the robotic arm's servo.

[0069] like Figure 7 The diagram shows the 5V regulated power supply circuit for the mobile car's drive circuit. On one hand, the +24V output from the supercapacitor is connected to the VIN pin of the first-stage step-down chip SCT2450. The chip's output (after inductor filtering) is connected to the 5V node, with a 100nF + 10μF filter capacitor connected in parallel at the 5V node. This provides a stable 5V output to power the EG3013S (H-bridge driver chip) in Figure 8, achieving a step-down output from 24V to 5V. On the other hand, the 5V node is connected to the VIN pin of the RT9013-33GB, the chip's GND pin is connected to system ground, and the output pin is connected to the 3.3V node. A 100nF filter capacitor is connected in parallel at the 3.3V node, providing a stable 3.3V output to power the EG3013S (H-bridge driver chip) in Figure 8. Figure 3 ADC chip, Figure 9 The encoder chip is powered to achieve a step-down output from 5V to 3.3V.

[0070] like Figure 8A , 8BThe FOC driver board H-bridge circuit shown uses four H-bridge circuits, employing the EG3013s driver chip and the NCEP4090GU MOSFET. It receives PWMA+, PWMB+, PWMA-, and PWMB- (PWM control signals output by the main control FPGA) and outputs them through OUT_A+ / OUT_B+ / OUT_A- / OUT_B-, which are connected to the stepper motor coils A+, B+, A-, and B- respectively. This allows the four H-bridges to control the on / off state of the voltages in the four stepper motor coils A-, A+, B-, and B+, thereby controlling the direction of the magnetic field and enabling the rotor to rotate to the designated position, thus driving the four stepper motors.

[0071] by Figure 8A Taking the OUT_A+ output as an example, the 5V input is connected to the Vcc pin of the EG3013S chip, and the system ground is connected to the GND pin; the PWMA+ signal output by the main control FPGA is connected to the HIN pin of the chip, and the LIN# pin is connected to a low level (or a complementary PWM signal); the VB pin of the chip is connected to the bootstrap capacitor C4 (10nF) to the OUT_A+ output terminal, providing the drive voltage for the upper arm MOSFET, realizing the power supply and signal input of the drive chip. The OUT terminal of the EG3013S is connected to the gate of the upper arm MOSFET (NCEP4090GU) after being current-limited by R3 (33Ω); the lower arm MOSFET ( Figure 8B The gate of the upper arm MOSFET is driven by the OUT terminal of another EG3013S + R5 (33Ω), realizing the alternating on / off of the upper and lower arm MOSFETs and driving the MOSFETs to work. 4V is connected to the drain of the upper arm MOSFET, and the source of the lower arm MOSFET is connected to the system ground; the source of the upper arm MOSFET and the drain of the lower arm MOSFET are connected to form the OUT_A+ output terminal, which is directly connected to the A+ coil of the stepper motor.

[0072] Meanwhile, the freewheeling diode D7 (FR107) is connected in reverse parallel between the drain and source of the MOSFET to absorb the reverse electromotive force of the motor coil; filter capacitors (such as C2 and C4) are connected in parallel between 24V and GND and between 5V and GND to suppress power supply noise interference with the PWM signal.

[0073] Therefore, the low-power PWM signal output by the FPGA is amplified by the EG3013S, and the H-bridge composed of MOSFETs is controlled to change the direction and magnitude of the current in the stepper motor coil A+, thereby realizing the forward rotation, reverse rotation, and speed adjustment of the motor, and finally driving the Mecanum wheel to move the trolley.

[0074] like Figure 9The stepper motor encoder circuit shown is designed to acquire the stepper motor angle using the MT6816CT chip magnetic encoder, thereby achieving closed-loop control of the stepper motor. The MT6816CT converts the motor angle into a digital value, which is transmitted to the FPGA via the SPI bus. The FPGA compares the target angle with the actual angle and adjusts the PWM drive signal shown in Figure 8 to correct the motor speed or angle, thus realizing angle detection and closed-loop control of the stepper motor and improving the positioning accuracy of the vehicle's movement (such as position calibration when parking on a bookshelf).

[0075] like Figure 9 As shown, a 3V3 circuit is connected to the VDD pin of the MT6816CT and systematically connected to the GND pin; capacitors C1 (1μF) and C2 (100nF) are connected in parallel between the VDD pin and GND to filter out the ripple of the supply voltage; the FPGA's SPI_SCLK pin is connected to the chip's SCLK pin, the FPGA's SPI_MISO pin is connected to the chip's MISO pin after being current-limited by resistor R2 (10Ω), the FPGA's SPI_MOSI pin is connected to the chip's MOSI pin, and the FPGA's chip select signal pin is connected to the chip's CSN pin (active low). The MT6816CT uses a built-in magnetic sensor to approach the stepper motor rotor, collects the rotor's angle information in real time, converts it into a digital value, and stores it in the chip's internal register.

[0076] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. An intelligent book delivery system for library collections based on FPGA, characterized in that, include: A mobile trolley driven by a stepper motor, the mobile trolley is equipped with two pairs of symmetrically distributed omnidirectional wheels, and the omnidirectional wheels are driven to move by the rotation output of the stepper motor; A multi-channel infrared tracking module, integrated on a mobile vehicle, consists of an infrared sensor and a comparison circuit, and is used for ground path recognition and yaw correction. The robotic arm actuator, integrated on the mobile vehicle, includes a multi-degree-of-freedom robotic arm and an actuator gripper at the end of the robotic arm, used for book grabbing and dropping; An image recognition module, mounted on a mobile vehicle, is used to identify and locate the presence of books; The main control FPGA module is electrically connected to and drives the multi-channel infrared tracking module, the robotic arm actuator, the image recognition module, and the drive module of the mobile trolley to control the operation of the intelligent book delivery system. When the image recognition module recognizes a book, it controls the movement of the mobile trolley and the robotic arm actuator to achieve linkage between the motion control of the mobile trolley and the grasping action of the robotic arm actuator. The image recognition module uses a PGL22H as the main image control FPGA, combined with an OV5640 camera. The OV5640 camera acquires image data within the field of view, and the PGL22H image control FPGA processes the image to locate whether there are books inside the book frame. An indicator light shows which position has a book. The PGL22H image control FPGA transmits the recognition results to the main control FPGA module via a UART serial port, which triggers the main control FPGA module to control the coordinated movement of the arm. For the movement and walking of the mobile car, the main control FPGA module outputs PWM signals to control the speed and direction of the four wheels of the car; for the robotic arm and gripper, the main control FPGA module drives the stepper motors at the joint positions of the robotic arm to achieve joint rotation, and drives the servo motors to achieve the opening and closing of the gripper; the main control FPGA module schedules the execution sequence of the mobile car's movement and the robotic arm's grasping action based on a finite state machine to ensure that the robotic arm accurately performs the grasping operation after reaching the target position; The loss ultrasonic obstacle avoidance module and the multi-channel infrared tracking module form a multi-sensor fusion perception. When an obstacle is detected, the main control FPGA module is set to prioritize triggering the preset obstacle avoidance algorithm and suspend the coordinated movement of the arm.

2. The FPGA-based intelligent book delivery system for libraries according to claim 1, characterized in that, The mobile trolley is equipped with omnidirectional wheels, all of which are Mecanum wheels. Each omnidirectional wheel is independently equipped with a stepper motor, which drives the corresponding Mecanum wheel to achieve omnidirectional movement of the mobile trolley.

3. The FPGA-based intelligent book delivery system for libraries according to claim 1, characterized in that, The multi-channel infrared tracking module includes eight TCRT5000 reflective infrared sensors and an LM393 comparator circuit, enabling automatic tracking and yaw correction, and thus controlling the movement of the mobile vehicle.

4. The FPGA-based intelligent book delivery system for libraries according to claim 3, characterized in that, The 8-channel TCRT5000 reflective infrared sensors are arranged in a double-layer layout of top layer + bottom layer, and are symmetrically distributed with 4 channels L1-L4 on the left and 4 channels R1-R4 on the right. The top layer layout of the PCB board of the multi-channel infrared tracking module is YCCGNDL4-L4, R1-R4, and the bottom layer layout is R4-R1, L1-L4. Ground black and white path information is collected by 8-channel TCRT5000 reflective infrared sensors. The 8-channel reflective signals are converted into digital quantities by two-channel LM393 comparators. The digital signals are output to the main control FPGA module for yaw error calculation. The FPGA corrects the path yaw by comparing the difference between the output values ​​of the left and right sensors.

5. The FPGA-based intelligent book delivery system for libraries according to claim 1, characterized in that, The driving module of the mobile vehicle uses the TMC229 driving chip.

6. The FPGA-based intelligent book delivery system for libraries according to claim 1, characterized in that, The mobile vehicle is powered by a supercapacitor power supply module and wirelessly charged by an LLC-based wireless charging system. The supercapacitor power supply module includes four 100F / 2.7V supercapacitors, whose positive and negative terminals are electrically connected to the supercapacitor detection module to detect the voltage value of the wireless charging supercapacitor.

7. The FPGA-based intelligent book delivery system for libraries according to claim 1, characterized in that, The wireless charging system includes a transmitter and a receiver. The transmitter is deployed inside the library and has two half-bridge drivers and an LCC transmitting resonant circuit for transmitting signals. The receiver is arranged on a mobile vehicle to receive AC signals, which are then converted into DC power through a rectifier bridge circuit and finally used to charge the supercapacitor power supply module.

8. The FPGA-based intelligent book delivery system for libraries according to any one of claims 1 to 7, characterized in that, The intelligent book delivery system also includes an ultrasonic obstacle avoidance module electrically connected to the main control FPGA module, which uses an HCSR04 ultrasonic sensor to detect whether there are obstacles in front. The ultrasonic obstacle avoidance module and the multi-channel infrared tracking module form a multi-sensor fusion perception. When an obstacle is detected, the main control FPGA module is set to prioritize triggering the preset obstacle avoidance algorithm and suspend the coordinated movement of the vehicle arm.

9. The FPGA-based intelligent book delivery system for libraries according to any one of claims 1 to 7, characterized in that, The main control FPGA module adopts the Ziguang Tongchuang PGL50H, which, together with the PGL22H image main control FPGA, forms a dual FPGA collaborative architecture to realize real-time and parallel processing of system control and image recognition.

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