Automatic parking system based on antimony selenide micron-belt near-infrared detector

Abstract

The invention discloses an automatic parking system based on an antimony selenide micron-belt near-infrared detector. The automatic parking system comprises the antimony selenide micron-belt near-infrared detector, a micro-control unit MCU and a parking driving module. The automatic parking function is started, the distance between the vehicle and the periphery is detected through the antimony selenide micron-belt near-infrared detector, and the MCU determines whether the target position is available or not; under the condition that available parking spaces exist, the MCU sends an instruction to the parking driving module to control the vehicle to be automatically parked; the antimony selenide micro-ribbon near-infrared detector comprises a weak current measurement module and an analog-to-digital conversion module; the weak current measurement module is used for converting a nanoampere-level current emitted by the antimony selenide microribbon device into an analog voltage signal of 0-2.44 V; and the analog-to-digital conversion module is used for converting the analog voltage signal into a digital signal and transmitting the digital signal to the MCU through the IIC interface. The double problems that in a traditional automatic parking system, the precision of a sensor is limited, and the cost is high are effectively solved.

Description

Technical Field

[0001] The invention belongs to the field of automatic parking, and in particular relates to an automatic parking system based on an antimony selenide micron-band near-infrared detector. Background Art

[0002] With the popularization of cars and the advancement of urbanization, the problem of parking space shortage has become increasingly prominent, and finding a suitable parking space has become a problem for drivers. In addition, manual parking is prone to scratches and collisions, especially in narrow parking lots. Therefore, the automatic parking system, as an important part of assisted driving technology, has received more and more attention.

[0003] In the related technologies, the automatic parking system is mainly based on ultrasonic or radar sensors for distance measurement and obstacle detection. Although it has achieved certain results, it also has shortcomings. Ultrasonic sensors are limited in detection distance and resolution. Although radar sensors have strong detection capabilities, they are expensive and large in size, which limits their widespread application. The camera-based visual parking system is easily affected by lighting conditions, resulting in unstable detection accuracy.

[0004] The present invention is based on an antimony selenide micro-ribbon device, combined with weak current measurement and analog-to-digital conversion modules, to achieve high-precision detection of environmental obstacles, improve detection accuracy and sensitivity, and reduce production costs. The device is extremely small, and this solution is particularly suitable for automatic parking in narrow urban spaces, with broad application prospects and commercial value. Summary of the invention

[0005] Purpose of the invention: The present invention provides an automatic parking system based on an antimony selenide micron-band near-infrared detector to solve the shortcomings of existing automatic parking technologies in terms of detection accuracy and cost.

[0006] Technical solution: The automatic parking system based on the antimony selenide micron-strip near-infrared detector described in the present invention comprises an antimony selenide micron-strip near-infrared detector, a microcontroller unit MCU, and a parking drive module;

[0007] The vehicle detects the distance between the vehicle itself and the surroundings through the antimony selenide micro-strip near-infrared detector, finds a parking space, avoids obstacles and judges the parking process; the MCU determines whether the target position is available. If there is an available parking space, the MCU sends a command to the parking drive module to control the vehicle to park automatically; the antimony selenide micro-strip near-infrared detector includes a weak current measurement module and an analog-to-digital conversion module; the weak current measurement module is used to convert the nanoampere current emitted by the antimony selenide micro-strip device into a 0-2.44V analog voltage signal; the analog-to-digital conversion module is used to convert the analog voltage signal into a digital signal, and then transmit the digital signal to the MCU through the IIC interface.

[0008] Furthermore, there are four antimony selenide micro-band near-infrared detectors, and the detector array formed is connected to the same I2C bus.

[0009] Furthermore, the weak current measurement module includes a resistor R1, a resistor R2, an amplifier, a capacitor C1, a capacitor C2 and a DC power supply V1; the resistor R1 is configured in series with the antimony selenide microbelt, and is used to convert the weak current signal into a corresponding voltage signal; the differential input end of the amplifier is respectively connected to the two ends of the resistor R1, and is used to differentially amplify the converted voltage signal to generate an amplified voltage signal proportional to the original weak current signal; the resistor R2 is connected to the output end of the measurement amplifier, and is used to adjust the gain of the amplifier; the capacitor C1 and the capacitor C2 are respectively connected in parallel to the power pin and the output end of the measurement amplifier, and are used to filter out high-frequency noise in the circuit; the DC power supply V1 is used to provide a stable operating voltage for the measurement amplifier.

[0010] Furthermore, the analog-to-digital conversion module includes an analog-to-digital converter, resistors R3 and R4 connected in series, a capacitor C3 and a DC power supply VCC; the input end of the analog-to-digital converter includes VIN+ and VIN-, which are respectively connected to an external signal source and ground, and are used to sample the input analog signal; the resistors R3 and R4 connected in series are pull-up resistors of the I2C interface of the analog-to-digital converter, which realize data communication with the MCU; the capacitor C3 is connected between the VDD pin of the integrated circuit and the ground, and is used to filter out power supply noise; the DC power supply VCC is used to provide an operating voltage for the integrated circuit.

[0011] Furthermore, the process of finding a parking space is as follows:

[0012] The distance data obtained by the antimony selenide micron-band near-infrared detector located on the side of the vehicle is compared with the preset threshold. If the value obtained by the antimony selenide micron-band near-infrared detector is greater than the preset threshold, it is judged that there is a parking space available and the parking procedure is started; if it is less than the preset threshold, it is judged that there is no parking space available on the side of the current vehicle position, and the vehicle continues to move longitudinally according to the values ​​of the antimony selenide micron-band near-infrared detectors in front and behind the vehicle to find a parking space.

[0013] Furthermore, the obstacle avoidance and parking progress determination are implemented as follows:

[0014] The antimony selenide micron-strip near-infrared detector on the side of the vehicle obtains the distance between the side of the vehicle and the edge of the parking lot. If the detection distance is greater than the preset threshold, it is determined that the vehicle has not been completely parked in the parking space and continues to move toward the side of the vehicle. If the detection distance is less than the preset threshold, it is determined that the vehicle has been parked in the parking space and the automatic parking is completed.

[0015] The antimony selenide micron-strip near-infrared detectors at the front and rear of the vehicle obtain the distance between the vehicle and the front and rear obstacles. The vehicle MCU subtracts the value of the rear detector from the value of the front detector to obtain the difference; if the difference is positive and greater than the preset threshold, the vehicle moves forward; if the difference is negative and greater than the preset threshold, the vehicle moves backward; if the absolute value of the difference is less than the preset threshold, the vehicle does not move forward or backward.

[0016] Furthermore, the resistance value of the resistor R1 is 220 kΩ; the resistance value of the resistor R2 is 5.1 kΩ.

[0017] Furthermore, the stable operating voltage is 3V.

[0018] Furthermore, the resistance value of the resistor R3 is 1 kΩ, and the resistance value of the resistor R4 is 10 kΩ.

[0019] Furthermore, the capacitance value of the capacitor C3 is 100 pF.

[0020] Beneficial effects: Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention is based on the high-precision environmental perception capability of the antimony selenide micro-band near-infrared detector, which effectively overcomes the dual problems of limited sensor accuracy and high cost in traditional automatic parking systems; by integrating weak current measurement with the analog-to-digital conversion module, the system can achieve accurate detection of obstacles and parking control, thereby significantly improving the overall safety and reliability of the automatic parking system; at the same time, the device has an extremely small device volume and a wide range of applications; the system has the significant advantages of low cost, high sensitivity and precise control, and is particularly suitable for narrow and complex parking scenes in cities, and can effectively reduce parking time, reduce accident risks, and greatly improve user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The working diagram of the automatic parking system based on the antimony selenide micron-strip near-infrared detector;

[0022] Figure 2 A flowchart of a specific automatic parking method provided by the present invention;

[0023] Figure 3 A block diagram of an implementation scheme of a near-infrared detector device circuit provided by the present invention;

[0024] Figure 4 A schematic diagram of the structure of an automatic parking device provided by the present invention;

[0025] Figure 5 The present invention provides a schematic structural diagram of a vehicle. DETAILED DESCRIPTION

[0026] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0027] The present invention proposes an automatic parking system based on an antimony selenide micron-strip near-infrared detector, which mainly includes an antimony selenide micron-strip near-infrared detector, a microcontroller unit MCU, and a parking drive module. The synergistic effect of each module realizes accurate perception of the parking environment and automatic parking control; Figure 1 As shown, the vehicle detects the distance between itself and the surroundings through an antimony selenide micron-strip near-infrared detector, searches for a parking space, avoids obstacles, and determines the parking process; the MCU determines whether the target position is available. If there is an available parking space, the MCU sends a command to the parking drive module to control the vehicle to park automatically.

[0028] The antimony selenide micro-strip near-infrared detector includes a weak current measurement module and an analog-to-digital conversion module; the weak current measurement module is used to convert the nanoampere current emitted by the antimony selenide micro-strip device into a 0-2.44V analog voltage signal; the analog-to-digital conversion module is used to convert the analog voltage signal into a digital signal, and then transmit the digital signal to the MCU through the IIC interface.

[0029] A weak current measurement module comprises: a resistor (R1) configured in series with an antimony selenide micro-strip, and used for converting a weak current signal into a corresponding voltage signal; an amplifier, whose differential input ends are respectively connected to the two ends of the resistor (R1), and used for differentially amplifying the converted voltage signal to generate an amplified voltage signal proportional to the original weak current signal; a resistor (R2), connected to the output end of the measurement amplifier, and used for adjusting the gain of the amplifier; a capacitor (C1) and a capacitor (C2), respectively connected in parallel to the power pin and the output end of the measurement amplifier, and used for filtering high-frequency noise in the circuit; and a direct current power supply (V1), used for providing a stable working voltage of 3.3V for the measurement amplifier.

[0030] The analog-to-digital conversion module comprises: an analog-to-digital converter, whose input ends include VIN+ and VIN-, which are respectively connected to an external signal source and ground, and are used to sample the input analog signal; resistors R3 and R4 connected in series, which are pull-up resistors of an I2C interface of the analog-to-digital converter, and realize data communication with an MCU; a capacitor (C3), which is connected between a VDD pin of an integrated circuit and ground, and is used to filter power supply noise; and a direct current power supply (VCC), which is used to provide an operating voltage for the integrated circuit.

[0031] The near-infrared detector contains an antimony selenide micro-strip device, and the weak current signal generated by it is converted into an analog voltage signal by the weak current measurement module, and then converted into a digital signal by the analog-to-digital conversion module, and transmitted to the MCU module through the IIC interface for processing. Specifically, the weak current measurement module converts the weak current into a corresponding voltage signal through the resistor R1, the amplifier amplifies the voltage signal, and then converts it into a digital signal through the analog-to-digital converter for subsequent processing and calculation.

[0032] The vehicle detects the distance between itself and the surroundings through the near-infrared detector, and the MCU determines whether the target location is available. After the system turns on the automatic parking function, the infrared detector detects the environment around the vehicle, and the MCU calculates the acquired data in real time to determine whether there is an available parking space. Among them, the near-infrared detectors installed in different positions of the vehicle work together to collect real-time distance information between the vehicle and surrounding obstacles. The MCU determines whether the target parking space meets the parking conditions based on this distance information.

[0033] When there is an available parking space, the MCU sends a command to the parking drive module to control the vehicle to park automatically. When the MCU determines that there is a parking space that meets the conditions, it sends a command to the parking drive module to control the vehicle to enter the automatic parking state. The parking drive module controls the vehicle's Mecanum wheels through the L298N driver chip to achieve lateral and longitudinal movement of the vehicle to ensure that the vehicle is parked smoothly in the parking space. Specifically, the left front wheel and right rear wheel of the vehicle reverse, and the right front wheel and left rear wheel rotate forward to achieve parallel movement of the vehicle to the left; reverse rotation moves the vehicle to the right to ensure accurate adjustment of the vehicle's position during parking.

[0034] like Figure 2As shown, a specific parking path planning method is disclosed. The automatic parking process starts with the MCU issuing a command, and the command starts the system to enter the automatic parking mode. In the system initialization stage, the MCU configures the near-infrared detector and assigns a unique I2C address to each detector through the I2C bus to ensure that the system can effectively distinguish the detection data of different positions. After the automatic parking is started, the detector begins to obtain the environmental information around the vehicle and continuously scans the distance of obstacles around the vehicle to identify available parking spaces. The vehicle width is set as the parking space recognition threshold in the MCU. When the value obtained by the vehicle side detector is greater than the vehicle width, it is judged that there is sufficient space for parking and the automatic parking process begins. The vehicle begins to move laterally to park in the parking space; the near-infrared detector installed on the side of the vehicle is used to monitor the distance between the side of the vehicle and the edge of the garage; when the detection distance is greater than the preset threshold, the MCU determines that the vehicle has not completely entered the parking space and continues to move toward the side of the vehicle; when the distance is less than the preset threshold, it is judged that the vehicle has successfully parked in the parking space, and the automatic parking process ends. At the same time, the near-infrared detectors at the front and rear of the vehicle are used to ensure that a safe distance is maintained from the front and rear obstacles during parking. The detectors at the front and rear of the vehicle obtain the distance between the vehicle and the front and rear obstacles. The vehicle MCU subtracts the value of the rear sensor from the value of the front sensor. If the difference is positive and greater than the preset threshold, the vehicle moves forward; if the difference is negative and greater than the preset threshold, the vehicle moves backward; if the absolute value of the difference is less than the preset threshold, the vehicle does not move forward or backward.

[0035] Figure 3 This is a block diagram of an implementation method of a near-infrared detector device circuit provided in an example of the present invention. The weak current measurement module is mainly based on the MAX44286 current monitoring operational amplifier. The MAX44286 amplifies the voltage on the resistor (R1), and the amplification factor can be selected. Since the selected MCU reference voltage is 2.44V, the voltage at the output end of the amplifier circuit should be limited to within 2.44V. And the design can measure weak current within, so R1 is selected in this circuit, that is, R1=220kΩ. Resistor (R2), whose resistance is 5.1kΩ, is connected to the output end of MAX44286 to adjust the gain of the amplifier. Capacitor (C1) and capacitor (C2) are respectively connected in parallel to the power pin and output end of the measuring amplifier to filter out high-frequency noise in the circuit.

[0036] The analog-to-digital conversion module in this example is mainly based on the MS1100 analog-to-digital conversion chip. The input ends of MS1100 include VIN+ and VIN-, which are respectively connected to the two ends of the resistor (R2) for sampling the input analog signal. The resistors R3 and R4 connected in series, where the resistance of R3 is 1kΩ and the resistance of R4 is 10kΩ, are pull-up resistors of the I2C interface of the analog-to-digital converter to achieve data communication with the MCU. The capacitor (C3), whose capacitance is 100pF, is connected between the VDD pin of the integrated circuit and the ground to filter out power supply noise.

[0037] like Figure 4 As shown in the figure, the automatic parking device mainly includes four antimony selenide micron-strip near-infrared detectors and an MCU module. The near-infrared detectors communicate with the MCU through the I2C bus. During the initialization phase, the MCU assigns a unique I2C address to each antimony selenide micron-strip near-infrared detector, and the MCU distinguishes different near-infrared detectors through the I2C address. Since each infrared detector has a different address, the detector array consisting of four detectors is connected to the same I2C bus in this example, which greatly reduces the hardware overhead.

[0038] In practical applications, Figure 5 It is a structural schematic diagram of a vehicle provided in an example of the present invention. The automatic parking device serves as the control core, and the vehicle's Mecanum wheels are connected to each other through two L298N vehicle drive modules to control its movement. The drive modules are respectively located at the front and rear of the vehicle, and each drive module controls two motors, and the Mecanum wheels are driven by the motors. The Mecanum wheels can achieve multi-directional movement, such as lateral, oblique and rotational, so that the vehicle can be flexibly parked in narrow or complex spaces. Specifically as follows: the left front wheel and the right rear wheel of the vehicle are reversed, the right front wheel and the left rear wheel rotate forward, and the vehicle moves parallel to the left side; the left front wheel and the right rear wheel of the vehicle rotate forward, the right front wheel and the left rear wheel are reversed, and the vehicle moves parallel to the right side. The entire system accurately controls the rotation direction and speed of the Mecanum wheel through the control signal sent by the automatic parking device to achieve the purpose of automatic parking.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An automatic parking system based on antimony selenide micro-strip near-infrared detector, characterized in that: It includes antimony selenide micron-strip near-infrared detector, microcontroller unit MCU, and parking drive module; The vehicle detects the distance between the vehicle itself and the surroundings through the antimony selenide micro-strip near-infrared detector, finds a parking space, avoids obstacles and judges the parking process; the MCU determines whether the target position is available. If there is an available parking space, the MCU sends a command to the parking drive module to control the vehicle to park automatically; the antimony selenide micro-strip near-infrared detector includes a weak current measurement module and an analog-to-digital conversion module; the weak current measurement module is used to convert the nanoampere current emitted by the antimony selenide micro-strip device into a 0-2.44V analog voltage signal; the analog-to-digital conversion module is used to convert the analog voltage signal into a digital signal, and then transmit the digital signal to the MCU through the IIC interface.

2. An automatic parking system based on antimony selenide micro-strip near-infrared detector, characterized in that: There are four antimony selenide micro-strip near-infrared detectors, and the detector array formed is connected to the same I2C bus.

3. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 1 is characterized in that: The weak current measurement module includes a resistor R1, a resistor R2, an amplifier, a capacitor C1, a capacitor C2 and a DC power supply V1; the resistor R1 is configured in series with the antimony selenide micro-ribbon, and is used to convert the weak current signal into a corresponding voltage signal; the differential input end of the amplifier is respectively connected to the two ends of the resistor R1, and is used to differentially amplify the converted voltage signal to generate an amplified voltage signal proportional to the original weak current signal; the resistor R2 is connected to the output end of the measuring amplifier, and is used to adjust the gain of the amplifier; the capacitor C1 and the capacitor C2 are respectively connected in parallel to the power pin and the output end of the measuring amplifier, and are used to filter out high-frequency noise in the circuit; the DC power supply V1 is used to provide a stable working voltage for the measuring amplifier.

4. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 1 is characterized in that: The analog-to-digital conversion module includes an analog-to-digital converter, resistors R3 and R4 connected in series, a capacitor C3 and a direct current power supply VCC; the input end of the analog-to-digital converter includes VIN+ and VIN-, which are respectively connected to an external signal source and ground, and are used to sample the input analog signal; the resistors R3 and R4 connected in series are pull-up resistors of the I2C interface of the analog-to-digital converter, and realize data communication with the MCU; the capacitor C3 is connected between the VDD pin of the integrated circuit and the ground, and is used to filter out power supply noise; the direct current power supply VCC is used to provide an operating voltage for the integrated circuit.

5. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 1 is characterized in that: The process of finding a parking space is as follows: The distance data obtained by the antimony selenide micron-band near-infrared detector located on the side of the vehicle is compared with the preset threshold. If the value obtained by the antimony selenide micron-band near-infrared detector is greater than the preset threshold, it is judged that there is a parking space available and the parking procedure is started; if it is less than the preset threshold, it is judged that there is no parking space available on the side of the current vehicle position, and the vehicle continues to move longitudinally according to the values ​​of the antimony selenide micron-band near-infrared detectors in front and behind the vehicle to find a parking space.

6. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 1, characterized in that: The obstacle avoidance and parking progress judgment implementation process is as follows: The antimony selenide micron-strip near-infrared detector on the side of the vehicle obtains the distance between the side of the vehicle and the edge of the parking lot. If the detection distance is greater than the preset threshold, it is determined that the vehicle has not been completely parked in the parking space and continues to move toward the side of the vehicle. If the detection distance is less than the preset threshold, it is determined that the vehicle has been parked in the parking space and the automatic parking is completed. The antimony selenide micron-strip near-infrared detectors at the front and rear of the vehicle obtain the distance between the vehicle and the front and rear obstacles. The vehicle MCU subtracts the value of the rear detector from the value of the front detector to obtain the difference; if the difference is positive and greater than the preset threshold, the vehicle moves forward; if the difference is negative and greater than the preset threshold, the vehicle moves backward; if the absolute value of the difference is less than the preset threshold, the vehicle does not move forward or backward.

7. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 3 is characterized in that: The resistance value of the resistor R1 is 220 kΩ; the resistance value of the resistor R2 is 5.1 kΩ.

8. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 3 is characterized in that: The stable operating voltage is 3V.

9. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 4, characterized in that: The resistance value of the resistor R3 is 1 kΩ, and the resistance value of the resistor R4 is 10 kΩ.

10. The automatic parking system based on antimony selenide micro-ribbon near-infrared detector according to claim 4, characterized in that: The capacitance value of the capacitor C3 is 100 pF.

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