An embedded ultrasonic sensor system

Abstract

The application discloses an embedded ultrasonic sensor system, and relates to the field of automobile ranging, which comprises the following steps: connecting a control motherboard to a vehicle through a CAN bus; connecting a power module to a central processing unit to provide voltage for the central processing unit; connecting a serial communication module to the central processing unit and the control motherboard respectively to realize data communication between the control motherboard and a radar control module; connecting an ultrasonic wave driving and data receiving module to an ultrasonic sensor group through the control motherboard to drive the ultrasonic sensor group and receive obstacle information and environmental temperature returned by the ultrasonic sensor group; and connecting the central processing unit to the ultrasonic wave driving and data receiving module to receive the obstacle information and the environmental temperature, and send the obstacle information compensated and corrected according to the environmental temperature to the vehicle. The application simultaneously measures temperature and distance by using a sensor with a temperature measuring function, can read temperature data at any time, and makes the ranging temperature compensation free from the dependence on temperature data of the vehicle end.

Description

Technical Field

[0001] This application relates to the field of automotive ranging, and more specifically, to an embedded ultrasonic sensor system. Background Technology

[0002] Currently, obstacle data acquired by vehicle-mounted systems primarily comes from millimeter-wave devices, laser devices, infrared devices, machine vision equipment, and ultrasonic devices. Among these, compared to other methods, ultrasonic waves have gained increasing popularity in vehicle-mounted systems due to their strong penetration, low attenuation, strong reflection capabilities, insensitivity to light, color, and electromagnetic fields, resistance to adverse weather conditions, simple ranging principle, high ranging accuracy, and low cost. As the integration of vehicle-mounted systems increases, the market demand for easily integrated embedded information acquisition systems specifically designed for vehicles is also growing. Simultaneously, the requirements for the anti-interference capabilities of ultrasonic sensor systems are becoming increasingly stringent.

[0003] To address the aforementioned issues, existing technologies have proposed embedded integrated radar systems, but these still suffer from the following shortcomings: ① The transmission between the control module and the sensors uses analog signals, making them susceptible to external interference that can affect product performance in real-world vehicle applications; ② The transmission and reception of each sensor channel require time-division multiplexing via analog switching chips, allowing only a maximum of two channels to be selected simultaneously, thus limiting the real-time performance of ranging response; ③ The system requires simultaneous input of both 12V and 5V power supplies, placing excessive demands on the embedded motherboard and compatibility issues. Summary of the Invention

[0004] This application provides an embedded ultrasonic sensor system to overcome at least one technical problem existing in the prior art.

[0005] This application provides an embedded ultrasonic sensor system, including: a radar control module, a control motherboard, and an ultrasonic sensor group; wherein, the radar control module includes a central processing unit, a power supply module, an ultrasonic driving and data receiving module, and a serial communication module; The control board is connected to the vehicle via a CAN bus to enable data communication with the vehicle. The power module is connected to the central processing unit and is used to provide voltage to the central processing unit; The serial communication module is connected to the central processing unit and the control motherboard respectively, and is used to realize data communication between the control motherboard and the radar control module; The ultrasonic drive and data receiving module is connected to the ultrasonic sensor group through the control motherboard, and is used to drive the ultrasonic sensor group and receive obstacle information and ambient temperature returned by the ultrasonic sensor group. The central processing unit is also connected to the ultrasonic drive and data receiving module, and is used to receive obstacle information and ambient temperature, and to send the obstacle information to the vehicle after compensating and correcting it according to the ambient temperature.

[0006] Optionally, the radar control module further includes a voltage detection and reset module; The voltage detection and reset module is connected to the power supply module and the central processing unit respectively, and is used to monitor the voltage of the central processing unit and reset the central processing unit when the voltage is abnormal.

[0007] Optionally, the radar control module further includes an ultrasonic power supply control module, used to turn on or off the power supply to the ultrasonic sensor group according to the instructions of the central processing unit.

[0008] Optionally, the ultrasonic power supply control module includes an NPN transistor Q1 and a P-channel MOSFET Q2; wherein, The source S of the P-channel MOSFET Q2 is connected to the input power supply, and the drain D is connected to the power supply terminal of the ultrasonic sensor. The base of the NPN transistor Q1 is connected to the central processing unit through resistor R1, and the collector is connected to the gate G of the P-channel MOSFET Q2 through resistor R3. The emitter and collector are grounded. A resistor R4 is connected between the source S and the gate G of the P-channel MOS transistor Q2. A resistor R2 is connected between the base and emitter of the NPN transistor Q1.

[0009] Optionally, the ultrasonic sensor group includes multiple ultrasonic sensors, and the ultrasonic driving and data receiving module is configured with an independent driving circuit and receiving circuit for each ultrasonic sensor; wherein, the driving circuit includes a resistor R5 and an NPN transistor Q3, and the receiving circuit includes a resistor R6 and an NPN transistor Q4. The base of the NPN transistor Q3 is connected to the first port of the central processing unit, the emitter is grounded, and the collector is connected to the first driving power supply through resistor R5 and to the signal terminal of the ultrasonic sensor through resistor R7. The signal terminal of the ultrasonic sensor is also connected to the base of the NPN transistor Q4 through a voltage divider circuit formed by voltage divider resistors R7 and R8. The emitter of the NPN transistor Q4 is grounded, the collector is connected to the second driving power supply through resistor R6 and to the second port of the central processing unit, and the base is connected to the signal terminal of the ultrasonic sensor through resistor R8.

[0010] Optionally, the ultrasonic driving and data receiving module further includes an electrostatic discharge protection device D1 and a filter capacitor C1, one end of which is connected to the signal terminal of the ultrasonic sensor, and the other end of which is grounded.

[0011] Optionally, it may also include an alarm device; The radar control module also includes an alarm drive module, which is connected to the central processing unit and the alarm device respectively, and is used to receive alarm information and drive the alarm device to emit a prompt sound.

[0012] Optionally, the ultrasonic sensor group includes a front ultrasonic sensor group, a rear ultrasonic sensor group, a left ultrasonic sensor group, and a right ultrasonic sensor group; each ultrasonic sensor group includes multiple ultrasonic sensors. The vehicle's gears include P, D, and R. When the gear is in P gear or the speed is greater than 15km / h, all ultrasonic sensors in the ultrasonic sensor group do not perform distance measurement. When the gear is in D or R, all ultrasonic sensors in the ultrasonic sensor group measure distance and send the data to the central processing unit. If the front ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a first threshold, the alarm device generates an alarm sound. If the rear ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a second threshold, the alarm device generates an alarm sound. If the left ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a third threshold, the alarm device generates an alarm sound. If the right ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a fourth threshold, the alarm device generates an alarm sound. When the gear is in D gear, the first threshold is greater than the second threshold, the third threshold, and the fourth threshold; when the gear is in R gear, the second threshold is greater than the first threshold, the third threshold, and the fourth threshold.

[0013] Optionally, the CAN communication module is also used to receive the vehicle's turn signal; When the gear is in D and the left turn signal is active, the third threshold is greater than the first threshold, the second threshold, and the fourth threshold. When the gear is in D and the right turn signal is active, the fourth threshold is greater than the first threshold, the second threshold, and the third threshold.

[0014] Optionally, the radar control module is connected to the control motherboard via a board-to-board connector or pads. The innovative aspects of this application's embodiments include: 1. In this embodiment, digital communication between the ultrasonic sensor and the radar control module is realized through the control motherboard. Therefore, it can support the simultaneous embedding and use of two radar control modules without mutual interference. It also supports the simultaneous transmission and reception of multiple sensors, resulting in higher real-time ranging response, which is one of the innovative points of this application embodiment.

[0015] 2. In this embodiment, both the ultrasonic signal and communication are digitally processed, which not only has a stronger anti-electromagnetic interference capability, but also allows the power supply and signal of the sensor to be connected to the control motherboard using ordinary automotive cables. Furthermore, it facilitates the digital calculation of temperature compensation by the central processing unit, which is one of the innovative points of this application embodiment.

[0016] 3. In this embodiment, a sensor with temperature measurement function is used to measure both temperature and distance simultaneously without the need for an additional temperature sensor. This not only simplifies the system, but also allows the radar control module to read temperature data at any time, freeing the ranging temperature compensation from dependence on temperature data from the vehicle. This is one of the innovative aspects of this application embodiment. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of an embedded ultrasonic sensor system provided in an embodiment of this application; Figure 2 A schematic diagram of the external structure of a radar control module provided in an embodiment of this application; Figure 3 This is another schematic diagram of the embedded ultrasonic sensor system provided in the embodiments of this application; Figure 4 A circuit structure diagram of an ultrasonic power supply control module provided in an embodiment of this application; Figure 5 This is a schematic diagram of a circuit structure for an ultrasonic driving and data receiving module provided in an embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0021] This application discloses an embedded ultrasonic sensor system. The following provides a detailed description of each system.

[0022] Figure 1 Please refer to the schematic diagram of an embedded ultrasonic sensor system provided in the embodiments of this application. Figure 1 The embedded ultrasonic sensor system 100 provided in this application embodiment includes: a radar control module, a control motherboard, and an ultrasonic sensor group; wherein, the radar control module includes a central processing unit, a power supply module, an ultrasonic driving and data receiving module, and a serial communication module; The control board is connected to the vehicle via a CAN bus to enable data communication with the vehicle. The power module is connected to the central processing unit (CPU) and is used to provide voltage to the CPU. The serial communication module is connected to the central processing unit and the control motherboard respectively, and is used to realize data communication between the control motherboard and the radar control module. The ultrasonic drive and data receiving module is connected to the ultrasonic sensor group through the control motherboard, and is used to drive the ultrasonic sensor group and receive obstacle information and ambient temperature returned by the ultrasonic sensor group. The central processing unit is also connected to the ultrasonic drive and data receiving module, and is used to receive obstacle information and ambient temperature, and to send the obstacle information to the vehicle after compensating and correcting it according to the ambient temperature.

[0023] For details, please refer to Figure 1The embedded ultrasonic sensor system 100 provided in this application embodiment includes a radar control module, a control motherboard, and an ultrasonic sensor group. The power supply of the control motherboard is connected to the vehicle's ACC power supply. ACC is an abbreviation for Adaptive Cruise Control, which refers to the adaptive cruise control power supply. It is activated by the vehicle key and is specifically designed to provide stable and reliable power support for various electronic systems of the vehicle. The system can work normally when its voltage range is within 9~36V.

[0024] The radar control module includes a central processing unit (CPU) and a power supply module. The power supply module is connected to both the control motherboard and the CPU, providing 12V power to the radar control module through the control motherboard. Therefore, it only requires a single 12V power input to operate, resulting in lower power supply requirements for the embedded motherboard and better adaptability. In this embodiment, the power supply module consists of an automotive-grade 5V fixed-output LDO (low dropout regulator) voltage regulator chip, reverse connection protection components, filtering components, and energy storage components. The control motherboard provides a stable and reliable operating voltage and current to the CPU through the power supply module.

[0025] The radar control module also includes a serial communication module, which connects to both the central processing unit and the control motherboard. It uses digital TTL (Transistor-Transistor Logic) to achieve digital communication between the radar control module and the control motherboard, effectively improving its electromagnetic interference resistance. Therefore, ordinary automotive cables can be used to connect the sensor's power and signal lines to the control motherboard. In this embodiment, the radar control module is assembled and integrated with the control motherboard via board-to-board connectors or stamp-shaped pads, allowing the traces on the control motherboard to transmit the sensor's power and signal lines to the radar control module through the board-to-board connectors. Figure 2 This is a schematic diagram of the external structure of a radar control module provided in an embodiment of this application. Its motherboard 30 integrates various circuits in the radar control module. The external dimensions are 35mm x 45mm. The board-to-board connectors can be specific 1.27mm pitch double-row 2x10Pin board-to-board connectors 10 and double-row 2x8Pin board-to-board connectors 20, which makes the size more compact, easy to embed and integrate, low cost, low power consumption and high system stability.

[0026] The CAN (Controller Area Network) bus of the control motherboard is connected to the vehicle's instrument panel or domain controller via a twisted-pair shielded automotive cable to receive information such as the vehicle's gear position and speed. After receiving the vehicle information, the control motherboard sends the gear position, speed, and other information received from the vehicle to the central processing unit (CPU) via a serial communication module. The CPU then determines whether distance measurement is needed based on the gear position, speed, and other information.

[0027] The radar control module also includes an ultrasonic drive and data receiving module. The ultrasonic drive and data receiving module is connected to the ultrasonic sensor group through the control motherboard. When ranging is required, the ultrasonic drive and data receiving module sends ranging commands to each sensor in a specific timing sequence. After receiving the ranging commands, the ultrasonic sensor group performs obstacle detection and sends the detected distance information to the ultrasonic drive and data receiving module.

[0028] In this application, digital communication between the ultrasonic sensor and the radar control module is realized through the control motherboard. Therefore, it can support the simultaneous embedding and use of two radar control modules without mutual interference, and supports the simultaneous transmission and reception of multiple sensors, resulting in higher real-time ranging response.

[0029] The ultrasonic drive and data receiving module is also connected to the central processing unit (CPU). Distance information undergoes preliminary processing by the ultrasonic drive and data receiving module, such as filtering and shaping, converting the received analog signal into a digital signal before sending it to the CPU. The CPU then analyzes the digital signal, such as using algorithms from specific software to determine the distance information to detect obstacles. Therefore, in this application, both the ultrasonic signal and communication are processed digitally, which not only provides stronger resistance to electromagnetic interference but also facilitates digital calculations for temperature compensation by the CPU.

[0030] Since temperature changes significantly affect the speed of sound, this application introduces temperature compensation. While the sensor returns vehicle information, it also reads the temperature of the vehicle's environment from the sensor. The central processing unit uses the calculation formula of temperature and speed of sound to compensate and correct the measured obstacle distance information, and transmits the compensated obstacle distance information to the control board through the serial communication module. Then, the control board provides the above data information to the vehicle instrument panel or domain controller for alarm or parking path planning, etc., through CAN communication.

[0031] It should be noted that this application uses a sensor with temperature measurement function to measure both temperature and distance simultaneously, without the need for an additional temperature sensor. This not only simplifies the system, but also allows the radar control module to read temperature data at any time, freeing the ranging temperature compensation from dependence on temperature data from the vehicle.

[0032] The radar control module also includes an alarm drive module, which is connected to the central processing unit (CPU). The CPU determines the alarm level based on the distance to obstacles detected by each sensor, using a specific threshold in the software, thus obtaining alarm information, which is then sent to the alarm drive module. To promptly alert the driver when an obstacle is detected, thereby improving driving safety, an alarm device is also installed. This alarm device is connected to the alarm drive module. When the distance to the detected obstacle reaches the threshold, the CPU sends alarm information to the alarm drive module, which then drives the alarm device to emit an alarm sound. Alternatively, the alarm information can be sent to the vehicle's instrument panel via CAN, and the instrument panel will then emit an alarm tone, providing an audio reminder to the driver when parking. In this embodiment, the alarm drive module is connected to the CPU's PWM port and consists of a single NPN transistor and an LC filter element. It can drive a passive piezoelectric buzzer or speaker; therefore, the alarm device can be a passive piezoelectric buzzer or speaker.

[0033] In this application, to enable obstacle measurement in all directions (front, rear, left, and right) of the vehicle and avoid collisions caused by blind spots while driving in any direction, the ultrasonic sensor group is divided into a front ultrasonic sensor group, a rear ultrasonic sensor group, a left ultrasonic sensor group, and a right ultrasonic sensor group, with each ultrasonic sensor group containing multiple ultrasonic sensors. Specifically, the front ultrasonic sensor group is installed at the front of the vehicle, for example, four ultrasonic sensors are installed on the front bumper; the rear ultrasonic sensor group is installed at the rear of the vehicle, for example, four ultrasonic sensors are installed on the rear bumper; the left ultrasonic sensor group is installed on the left side of the vehicle, for example, one ultrasonic sensor is installed near the skin of the front and rear wheels on the left side; and the right ultrasonic sensor group is installed on the right side of the vehicle, for example, one ultrasonic sensor is installed near the skin of the front and rear wheels on the right side.

[0034] When the vehicle's ACC power is turned on, the radar control module first enters the power-on self-test state. After the self-test is completed, it obtains the vehicle's status information, such as gear position, speed, and turn signals, from the vehicle through the control motherboard. Then, based on the vehicle's status information, it determines whether distance measurement is needed, thereby determining the working conditions of each ultrasonic sensor.

[0035] The vehicle's gears include P (Park), D (Drive), and R (Reverse). When the gear is in P or the vehicle speed exceeds 15 km / h, all sensors do not perform distance measurement. However, when the gear is in D or R, all ultrasonic sensors in the ultrasonic sensor group perform distance measurement and send the data to the central processing unit. Typically, ultrasonic sensor alarms are divided into long-range and short-range alarm modes. For example, a long-range alarm mode might indicate an obstacle within 3.5 meters, while a short-range alarm mode might indicate an obstacle within 1 meter. Based on this, when all ultrasonic sensors are performing distance measurement, the alarm distance thresholds for each direction's ultrasonic sensors differ depending on the gear position.

[0036] For example, in this embodiment, the distance threshold for the ultrasonic sensors in the front-end ultrasonic sensor group is set as a first threshold, the distance threshold for the ultrasonic sensors in the rear-end ultrasonic sensor group is set as a second threshold, the distance threshold for the ultrasonic sensors in the left-end ultrasonic sensor group is set as a third threshold, and the distance threshold for the ultrasonic sensors in the right-end ultrasonic sensor group is set as a fourth threshold. That is, if the front-end ultrasonic sensor detects an obstacle and the distance to the obstacle is less than the first threshold, the alarm device will sound an alarm; if the rear-end ultrasonic sensor detects an obstacle and the distance to the obstacle is less than the second threshold, the alarm device will sound an alarm; if the left-end ultrasonic sensor detects an obstacle and the distance to the obstacle is less than the third threshold, the alarm device will sound an alarm; and if the right-end ultrasonic sensor detects an obstacle and the distance to the obstacle is less than the fourth threshold, the alarm device will sound an alarm.

[0037] When the vehicle is moving forward, the ultrasonic sensors in the front ultrasonic sensor group can be set to long-range alarm mode, while the other ultrasonic sensors are set to short-range alarm mode. Therefore, when the gear is in D gear, the first threshold is set to be greater than the second, third, and fourth thresholds. It should be noted that the values ​​of the second, third, and fourth thresholds can be equal or unequal at this time, and this application does not limit this.

[0038] Similarly, when the vehicle is reversing, the ultrasonic sensors in the rear ultrasonic sensor group are set to long-range alarm mode, while the other ultrasonic sensors are set to short-range alarm mode. Therefore, when the gear is in reverse (R), the second threshold is set to be greater than the first, third, and fourth thresholds. At this time, the values ​​of the first, third, and fourth thresholds can be equal or unequal; this application does not impose any limitation on this.

[0039] In addition to forward and backward movement, there is also the situation of turning. When the vehicle turns, the ultrasonic sensor in the corresponding direction needs to be set to long-range alarm mode, while the ultrasonic sensors in other directions need to be set to short-range alarm mode. Therefore, in this embodiment, the control board also receives the vehicle's turn signal via CAN and sends it to the radar control module, thereby determining whether the vehicle has turned based on the turn signal.

[0040] When the gear is in Drive (D) and the turn signal is left, the ultrasonic sensor in the left-hand ultrasonic sensor group needs to be set to long-range alarm mode, while the other ultrasonic sensors are set to short-range alarm mode. This means the third threshold is set to be greater than the first, second, and fourth thresholds. In this case, the values ​​of the second, first, and fourth thresholds can be equal or unequal; this application does not impose any limitation on this. Similarly, when the gear is in Drive (D) and the turn signal is right, the ultrasonic sensor in the right-hand ultrasonic sensor group needs to be set to long-range alarm mode, while the other ultrasonic sensors are set to short-range alarm mode. This means the fourth threshold is set to be greater than the first, second, and third thresholds. In this case, the values ​​of the second, third, and first thresholds can be equal or unequal; this application does not impose any limitation on this.

[0041] Optionally, Figure 3 For another structural schematic diagram of the embedded ultrasonic sensor system provided in the embodiments of this application, please refer to... Figure 3 The radar control module also includes a voltage detection and reset module; the voltage detection and reset module is connected to the power supply module and the central processing unit respectively, and is used to monitor the voltage of the central processing unit and reset the central processing unit when the voltage is abnormal.

[0042] For details, please refer to Figure 3 In this embodiment, the radar controller also includes a voltage detection and reset module. This module can be built from a low-cost watchdog reset chip and has a voltage monitoring function to monitor the voltage of the central processing unit (CPU). When the CPU voltage is lower than the voltage threshold, the voltage detection and reset module sends a low-level signal to the CPU to reset and restart it.

[0043] Optionally, Figure 4 Please refer to the circuit structure diagram of the ultrasonic power supply control module provided in the embodiments of this application. Figure 4The radar control module also includes an ultrasonic power supply control module, used to turn the power supply to the ultrasonic sensor group on or off according to the instructions of the central processing unit. The ultrasonic power supply control module includes an NPN transistor Q1 and a P-channel MOSFET Q2; the source (S) of the P-channel MOSFET Q2 is connected to the input power supply, and the drain (D) is connected to the power supply terminal of the ultrasonic sensor; the base of the NPN transistor Q1 is connected to the central processing unit through a resistor R1, and the collector is connected to the gate (G) of the P-channel MOSFET Q2 through a resistor R3; the emitter is grounded; a resistor R4 is connected between the source (S) and gate (G) of the P-channel MOSFET Q2; and a resistor R2 is connected between the base and emitter of the NPN transistor Q1.

[0044] For details, please refer to Figure 4 In the embedded ultrasonic sensor system provided in this embodiment, the radar control module further includes an ultrasonic power supply control module, which includes an NPN transistor Q1 and a P-channel MOSFET Q2. The source (S) of the P-channel MOSFET Q2 is connected to the input power supply, and the drain (D) is connected to the power supply terminal of the ultrasonic sensor. The base of the NPN transistor Q1 is connected to the central processing unit via resistor R1, and the collector is connected to the gate (G) of the P-channel MOSFET Q2 via resistor R3. The emitter is grounded. A resistor R4 is connected between the source (S) and gate (G) of the P-channel MOSFET Q2. A resistor R2 is connected between the base and emitter of the NPN transistor Q1.

[0045] When the CPU pin outputs a high level, this high level is sent to the base of Q1 through resistor R1. Since the emitter is grounded, the base voltage is higher than the emitter voltage, and Q1 receives base current and enters saturation conduction, making the collector and emitter of Q1 approximately short-circuited. Because the collector-emitter junction of Q1 is grounded, the gate G of MOSFET Q2 is pulled low to a potential close to 0V through resistor R3. Since the source S of Q2 is connected to the input power supply, the gate G is pulled low to 0V, which causes the voltage V between the gate G and the source S to... GS It is a negative value. When V GS When the value is negative and its absolute value is greater than its turn-on voltage, the MOSFET Q2 will turn on, and the current can flow from the source S to the drain D of Q2, thereby powering the ultrasonic sensor.

[0046] Conversely, when the CPU pin outputs a low level, Q1 is completely off, and the collector and emitter of Q1 are open-circuited. Since Q1 is off, there is no longer a pull-down effect on the gates of R3 and Q2. Therefore, resistor R4 pulls the gate voltage of Q2 up to the same potential as its source. At this time, the gate and source voltages V of Q2 are... GS It is 0V. When V GS When the voltage is 0V, MOSFET Q2 is turned off, and current cannot flow from the source S to the drain D of Q2, thus cutting off the sensor power supply.

[0047] Optionally, Figure 5 Please refer to the schematic diagram of a circuit structure for an ultrasonic driving and data receiving module provided in an embodiment of this application. Figure 5 The ultrasonic sensor group includes multiple sensors. The ultrasonic driving and data receiving module configures an independent driving circuit 40 and a receiving circuit 50 for each sensor. The driving circuit 40 includes a resistor R5 and an NPN transistor Q3, and the receiving circuit 50 includes a resistor R6 and an NPN transistor Q4. The base of the NPN transistor Q3 is connected to the first port of the central processing unit, its emitter is grounded, and its collector is connected to the first driving power supply through resistor R5 and to the signal terminal of the ultrasonic sensor through resistor R7. The signal terminal of the ultrasonic sensor is also connected to the base of the NPN transistor Q4 through a voltage divider circuit formed by voltage divider resistors R7 and R8. The emitter of the NPN transistor Q4 is grounded, its collector is connected to the second driving power supply through resistor R6 and to the second port of the central processing unit, and its base is connected to the signal terminal of the ultrasonic sensor through resistor R8. The ultrasonic driving and data receiving module also includes an electrostatic discharge (ESD) protection device D1 and a filter capacitor C1. One end of the ESD protection device D1 and the filter capacitor C1 are both connected to the signal terminal of the ultrasonic sensor, and the other end is grounded.

[0048] Specifically, the ultrasonic driving and data receiving module in this application can support up to 12 AK1 ultrasonic sensors simultaneously. The module drives the ultrasonic sensors and receives their signals. To avoid interference between the various ultrasonic sensors and enable them to operate synchronously or in a time-sharing manner, the ultrasonic driving and data receiving module in this application provides each sensor with an independent driving circuit 40 and receiving circuit 50. The driving circuit 40 drives the ultrasonic sensor to emit ultrasonic waves, and the receiving circuit 50 receives the echo signals returned by the sensor.

[0049] Please refer to Figure 5 The driving circuit 40 includes a pull-up resistor R5 and an NPN transistor Q3. The base of the NPN transistor Q3 is connected to the first port Port1 of the central processing unit, the emitter is grounded, and the collector is connected to the first driving power supply (such as 12V) through the resistor R5 and to the signal terminal of the ultrasonic sensor through the resistor R7.

[0050] When ultrasonic wave emission is not required, the NPN transistor Q3 is cut off due to its low base level when the CPU's first port (Port1) outputs a low level of 0V. At this time, current flows through the pull-up resistor R5 to the signal terminal of the ultrasonic sensor, pulling the voltage at that point up to the first drive power supply (e.g., 12V), making the voltage across the ultrasonic sensor equal and eliminating voltage difference, thus preventing it from operating. When ultrasonic wave emission is required, the CPU's first port (Port1) outputs a brief high-level pulse. This high level drives the base of Q3, causing Q3 to quickly enter saturation conduction. After Q3 conducts, because the emitter is grounded, the signal terminal of the ultrasonic sensor is rapidly pulled down to near 0V, generating a steep falling edge from 12V to 0V at the sensor's signal terminal—a negative pulse—thus exciting the ultrasonic sensor to emit ultrasonic waves. Resistor R7 acts as a current limiter and isolator during this process, preventing a sudden large current from damaging Q3.

[0051] When the high-level pulse at the first port Port1 ends, it returns to the low level, and Q3 returns to the cutoff state. At this time, the sensor's signal terminal is pulled up to the first drive power supply again through resistor R5, waiting to receive the echo.

[0052] The receiving circuit 50 includes a pull-up resistor R6 and an NPN transistor Q4; the signal terminal of the ultrasonic sensor is also connected to the base of the NPN transistor Q4 through a voltage divider circuit consisting of voltage divider resistors R7 and R8; the emitter of the NPN transistor Q4 is grounded, the collector is connected to a second drive power supply (e.g., 5V) through resistor R6 and connected to the second port Port2 of the central processing unit, and the base is connected to the signal terminal of the ultrasonic sensor through resistor R8.

[0053] When there is no echo, the signal terminal voltage of the sensor is the first drive power supply (12V). This voltage is attenuated by the voltage divider circuit composed of R7 and R8 before reaching the base of Q4. Therefore, by adjusting the resistance values ​​of R7 and R8, the base voltage V of Q4 can be adjusted. b When the voltage is low, Q4 is in the off state. At this time, the collector of Q4 is pulled up to the second drive power supply (e.g., 5V) by the pull-up resistor R6, so the second port Port2 of the central processing unit detects a high level.

[0054] When an echo is present and sufficiently strong, it will cause a noticeable negative glitch in the sensor signal terminal voltage. This glitch, through a voltage divider circuit, generates a current at the base of Q4 sufficient to bring it from the cutoff state to the conduction state. After Q4 turns on, since its emitter is grounded, its collector voltage (i.e., the voltage at Port2) will be rapidly pulled down from 5V to near 0V. Therefore, a falling edge from high (5V) to low (0V) will be observed at the second port of the central processing unit (Port2). The timing of this falling edge represents the arrival time of the echo.

[0055] In addition, the ultrasonic drive and data receiving module also includes an electrostatic discharge (ESD) protection device D1 and a filter capacitor C1. One end of both the ESD protection device D1 and the filter capacitor C1 is connected to the signal terminal of the ultrasonic sensor, and the other end is grounded. This purifies the signal and protects the circuit from external instantaneous high-voltage spikes and high-frequency noise interference, effectively reducing the probability of false alarms or missed alarms caused by noise interference, thus enabling the system to operate stably even in the complex electromagnetic environment of an automotive system. Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application.

[0056] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An embedded ultrasonic sensor system, characterized in that, include: The radar control module comprises a control motherboard and an ultrasonic sensor array; wherein the radar control module includes a central processing unit, a power supply module, an ultrasonic drive and data receiving module, and a serial communication module. The control board is connected to the vehicle via a CAN bus to enable data communication with the vehicle. The power module is connected to the central processing unit and is used to provide voltage to the central processing unit; The serial communication module is connected to the central processing unit and the control motherboard respectively, and is used to realize data communication between the control motherboard and the radar control module; The ultrasonic drive and data receiving module is connected to the ultrasonic sensor group through the control motherboard, and is used to drive the ultrasonic sensor group and receive obstacle information and ambient temperature returned by the ultrasonic sensor group. The central processing unit is also connected to the ultrasonic drive and data receiving module, and is used to receive obstacle information and ambient temperature, and to send the obstacle information to the vehicle after compensating and correcting it according to the ambient temperature.

2. The embedded ultrasonic sensor system according to claim 1, characterized in that, The radar control module also includes a voltage detection and reset module; The voltage detection and reset module is connected to the power supply module and the central processing unit respectively, and is used to monitor the voltage of the central processing unit and reset the central processing unit when the voltage is abnormal.

3. The embedded ultrasonic sensor system according to claim 1, characterized in that, The radar control module also includes an ultrasonic power supply control module, which is used to turn on or off the power supply to the ultrasonic sensor group according to the instructions of the central processing unit.

4. The embedded ultrasonic sensor system according to claim 3, characterized in that, The ultrasonic power supply control module includes an NPN transistor Q1 and a P-channel MOSFET Q2; wherein... The source S of the P-channel MOSFET Q2 is connected to the input power supply, and the drain D is connected to the power supply terminal of the ultrasonic sensor. The base of the NPN transistor Q1 is connected to the central processing unit through resistor R1, and the collector is connected to the gate G of the P-channel MOSFET Q2 through resistor R3. The emitter and collector are grounded. A resistor R4 is connected between the source S and the gate G of the P-channel MOS transistor Q2. A resistor R2 is connected between the base and emitter of the NPN transistor Q1.

5. The embedded ultrasonic sensor system according to claim 1, characterized in that, The ultrasonic sensor group includes multiple ultrasonic sensors, and the ultrasonic driving and data receiving module is configured with an independent driving circuit and receiving circuit for each ultrasonic sensor; wherein, the driving circuit includes a resistor R5 and an NPN transistor Q3, and the receiving circuit includes a resistor R6 and an NPN transistor Q4. The base of the NPN transistor Q3 is connected to the first port of the central processing unit, the emitter is grounded, and the collector is connected to the first driving power supply through resistor R5 and to the signal terminal of the ultrasonic sensor through resistor R7. The signal terminal of the ultrasonic sensor is also connected to the base of the NPN transistor Q4 through a voltage divider circuit formed by voltage divider resistors R7 and R8. The emitter of the NPN transistor Q4 is grounded, the collector is connected to the second driving power supply through resistor R6 and to the second port of the central processing unit, and the base is connected to the signal terminal of the ultrasonic sensor through resistor R8.

6. The embedded ultrasonic sensor system according to claim 1, characterized in that, The ultrasonic driving and data receiving module also includes an electrostatic protection device D1 and a filter capacitor C1. One end of the electrostatic protection device D1 and the filter capacitor C1 are both connected to the signal terminal of the ultrasonic sensor, and the other end is grounded.

7. The embedded ultrasonic sensor system according to claim 1, characterized in that, It also includes alarm devices; The radar control module also includes an alarm drive module, which is connected to the central processing unit and the alarm device respectively, and is used to receive alarm information and drive the alarm device to emit a prompt sound.

8. The embedded ultrasonic sensor system according to claim 7, characterized in that, The ultrasonic sensor group includes a front ultrasonic sensor group, a rear ultrasonic sensor group, a left ultrasonic sensor group, and a right ultrasonic sensor group; each ultrasonic sensor group includes multiple ultrasonic sensors. The vehicle's gears include P, D, and R. When the gear is in P gear or the speed is greater than 15km / h, all ultrasonic sensors in the ultrasonic sensor group do not perform distance measurement. When the gear is in D or R, all ultrasonic sensors in the ultrasonic sensor group measure distance and send the data to the central processing unit. If the front ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a first threshold, the alarm device generates an alarm sound. If the rear ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a second threshold, the alarm device generates an alarm sound. If the left ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a third threshold, the alarm device generates an alarm sound. If the right ultrasonic sensor group detects an obstacle and the distance to the obstacle is less than a fourth threshold, the alarm device generates an alarm sound. When the gear is in D gear, the first threshold is greater than the second threshold, the third threshold, and the fourth threshold; when the gear is in R gear, the second threshold is greater than the first threshold, the third threshold, and the fourth threshold.

9. The embedded ultrasonic sensor system according to claim 8, characterized in that, The control motherboard receives the vehicle's turn signal via the CAN bus; When the gear is in D and the left turn signal is active, the third threshold is greater than the first threshold, the second threshold, and the fourth threshold. When the gear is in D and the right turn signal is active, the fourth threshold is greater than the first threshold, the second threshold, and the third threshold.

10. The embedded ultrasonic sensor system according to claim 1, characterized in that, The radar control module is connected to the control motherboard via a board-to-board connector or solder pads.

Images