State monitoring and display system for cab of fire engine
阅读说明：本技术 一种消防车驾驶室状态监控及显示系统 (State monitoring and display system for cab of fire engine ) 是由 石巧婷 乔安营 张兵强 常彦凯 李朝飞 刘沛漾 潘超亚 李永奇 于 2019-10-29 设计创作，主要内容包括：本发明提供一种消防车驾驶室状态监控及显示系统,包括电脑端、驾驶室前端显示屏以及消防车后端控制系统,其中电脑端通过DTU数据传输线连接,驾驶室前端显示屏与消防车后端控制系统之间通过串口通信电路连接,采用MSC-51系列的STC15F2K16S2单片机,消防车驾驶室状态监控及显示系统具有：多个传感器信号采集电路、LCD液晶显示电路、键盘控制电路、蜂鸣器及LED灯报警电路和串口通信电路。形成一个完整、全面的监控显示控制系统,使救援工作更高效,速度更快。(The invention provides a monitoring and displaying system for the state of a cab of a fire fighting truck, which comprises a computer end, a front-end display screen of the cab and a rear-end control system of the fire fighting truck, wherein the computer end is connected through a DTU data transmission line, the front-end display screen of the cab is connected with the rear-end control system of the fire fighting truck through a serial port communication circuit, an MSC-51 series STC15F2K16S2 single chip microcomputer is adopted, and the monitoring and displaying system for the state of the cab of the fire fighting truck comprises: the device comprises a plurality of sensor signal acquisition circuits, an LCD (liquid crystal display) circuit, a keyboard control circuit, a buzzer, an LED lamp alarm circuit and a serial port communication circuit. A complete and comprehensive monitoring display control system is formed, so that the rescue work is more efficient and faster.)
1. The utility model provides a fire engine driver's cabin condition monitoring and display system which characterized in that: the system comprises a computer end, a cab front end display screen and a fire engine rear end control system, wherein the computer end is connected through a DTU data transmission line, the cab front end display screen is connected with the fire engine rear end control system through a serial port communication circuit, the fire engine cab state monitoring and displaying system adopts an MSC-51 series STC15F2K16S2 single chip microcomputer, and the fire engine cab state monitoring and displaying system comprises: a plurality of sensor signal acquisition circuits, LCD liquid crystal display circuit, keyboard control circuit, bee calling organ and LED lamp warning circuit and serial communication circuit, a plurality of sensor signal acquisition circuits interconnect for gather the status information of fire engine, LCD liquid crystal display circuit sets up inside the fire engine driver's cabin, a final circuit for showing the status information of fire engine, keyboard control circuit with LCD liquid crystal display circuit connects for control passes through keyboard input control information, bee calling organ and LED lamp warning circuit establish ties or connect in parallel, when taking place carry out sound and/or light warning under the condition that the status information of fire engine needs to report to the police, serial communication circuit is used for monitoring and display system handles the information transfer of the display output of final data from the collection of signal.
2. The fire engine cab status monitoring and display system of claim 1, wherein: the sensor signal acquisition circuit is used for acquiring 4 signals of bucket loading, amplitude variation angle, lifting height and fire scene temperature, and the dynamic parameters required to be monitored by the monitoring and display system are as follows: the sensor signal acquisition circuit comprises a force measuring sensor, an inclination angle sensor, a rotary encoder, an angle sensor, a wind speed sensor, a smoke sensor, a temperature sensor and an ultrasonic sensor, wherein the force measuring sensor is an ST-27 cantilever beam type force measuring sensor, one end of the force measuring sensor is fixed, the other end of the force measuring sensor is loaded and can be pulled and pressed, the sensor outputs a voltage signal of 0-5V, the analog signal is required to be converted into digital quantity through an A/D conversion circuit and transmitted to a main controller for processing, and the installation position of the sensor is positioned between a bottom plate and an outer frame of the working platform; the inclination angle sensor is an TQG-S series high-precision one-dimensional inclination angle sensor for measuring angle signals in real time, the sensor comprises three signal wires, a red wire is connected with the positive electrode of a power supply, a black wire is grounded, a yellow wire is an output signal wire of an X axis, the inclination angle sensor outputs a 4-20mA current signal or a 1-5V voltage signal, an A/D conversion circuit converts an analog signal into a digital quantity to be transmitted to a main controller for processing, and the analog signal is installed on the outer side of a ladder frame telescopic arm; the rotary encoder is selected as an E6B2-CWZ1X500PPR incremental photoelectric encoder under an ohm dragon and used for measuring the height of the ladder frame operation, digital quantity signals are output by the rotary encoder and directly connected with a main controller for operation processing, the rotary encoder is installed on a bearing of a piston rod magnetic steel wheel, the magnetic steel wheel rotates when the piston rod moves, the encoder also rotates, the pulse number is finally calculated, a P2.0 pin of a single chip microcomputer is used for representing A-phase pulses output by the rotary encoder, the P2.1 pin is directly connected with an external interrupt INT0 of the main single chip microcomputer and is directly connected with a P3.4 pin of the main single chip microcomputer. (ii) a The angle sensor is selected to be a CK-1 angle sensor, the CK-1 angle sensor adopts an analog quantity output form, carries out A/D conversion on the analog quantity output form and then sends the analog quantity to the main controller, and the main controller can output the analog quantity and is arranged below the rotary table; the wind speed sensor is an HL-FSX1 integrated wind speed and direction sensor of a spark tester, and is output in various modes of 4-20mA current, 0-5V voltage, RS232, RS485 and TTL signals, and is arranged on a working platform to measure wind speed; the smoke sensor is an MQ-2 smoke sensor; the temperature sensor is a DS18B20 sensor, data transmission is carried out in a digital mode of a one-line bus, only one signal line is needed for collecting temperature signals, the temperature measurement range is-55-125 ℃, information is transmitted through a single-line interface, a DQ end of the temperature sensor is an output signal line and is directly connected with a P2.7 pin of the single chip microcomputer, VCC is connected with a 5V power supply for power supply, and GND is grounded; the ultrasonic sensor is a piezoelectric ultrasonic sensor.
3. The system as claimed in claim 2, wherein the force of the ST-27 cantilever beam type load cell is applied to the free end, two strain gauges are respectively adhered to the upper and lower surfaces near the fixed end of the beam, and the two strain gauges are connected to form a bridge circuit, when the load is increased, the sensitive flashover resistance R2R 3 is changed to increase the output △ U 01And finally, an A/D conversion circuit is needed to convert the analog electrical signal into a digital electrical signal and input the digital electrical signal to a single chip microcomputer to complete measurement of the bucket load, the ST-27 cantilever beam type force transducer is fixed between the outer frame of the working platform and the bearing plane, the supporting points are close to the periphery and are uniformly distributed, under the action of gravity, an elastic body of the transducer generates elastic deformation, a resistance strain gage adhered to the surface is deformed to change the resistance value of the resistance strain gage, and the A/D conversion circuit can convert the change of the resistance value into a corresponding digital electrical signal through corresponding measurement.
4. The fire engine cab status monitoring and display system of claim 2, wherein: the A/D conversion circuit is used for carrying out A/D conversion on two paths of signals with bucket loading and amplitude variation angles, an ADC0832 conversion chip is arranged in the A/D conversion circuit, a 5V power supply is used for supplying power, the input voltage is between 0 and 5V, the working frequency is 250KHz, the conversion time is 32us, the power consumption is usually only 15MW, the input level and the output level of the A/D conversion circuit are compatible with the TTL/CMOS level, wherein the low level of a chip selection enabling signal is effective, the P1.4 pin of a single chip is connected, CH0 and CH1 are respectively an analog input channel 0 and a channel 1, the channels are respectively connected with a 5K potentiometer, respectively represent bucket loading signals and amplitude variation angle signals, and the change of the input signals is simulated by changing the resistance value of the potentiometer; CLK is the clock input end of the chip and is connected with a P1.5 pin of the single chip; DI denotes the input of the data signal, whose function is to select the channel, D0 denotes the output of the data signal, whose function is to convert the data, which are all connected to pin P1.6 of the single-chip microcomputer.
5. The fire engine cab status monitoring and display system of claim 1, wherein: the LCD liquid crystal display circuit comprises an LCD12864 liquid crystal display, the working voltage is 3-5.5V, the working temperature is 0-60 ℃, a serial and parallel communication mode is supported, the liquid crystal display of the final system consists of a monitoring startup interface, a data monitoring interface and a parameter rated value setting interface 3 large interfaces, a 10K potentiometer is connected for voltage adjustment, two ends of the potentiometer are respectively connected with VDD and VSS, DB0-DB7 ends are respectively connected with P0.0-P0.7 pins of a single chip microcomputer, CS1, CS2, RS and R/W, E are connected with P2.0-P2.4 pins of the single chip microcomputer, and negative pressure is output from a VOUT port and is transmitted to a V0 port through the 10K potentiometer.
6. The fire engine cab status monitoring and display system of claim 1, wherein: the keyboard control circuit comprises two groups of keys, wherein the first group of keys is responsible for setting the content displayed on the LCD 12864: k1 is used for making the data monitoring interface on the LCD enter the interface for setting the rated value of the parameter, once entering the interface for setting the rated value of the parameter, the rated value of the parameter to be measured can be set, K2 is used for increasing the rated value, K3 is used for reducing the rated value, after setting, the key K4 makes the interface for setting the rated value of the parameter return to the interface for monitoring the data, and the parameter to be measured is monitored in real time; the other group of keys controls the telescopic action of the aerial ladder fire truck: pressing k1, the aerial ladder fire truck ladder frame begins to extend; pressing k2 to stop the action; k3 is the switching of the expansion of the ladder frame, press k3, the movement of the ladder frame changes from expansion to contraction, press k3, the movement changes from contraction to expansion; k4, the expansion and contraction speed is increased; k5 reduces the telescoping speed.
7. The fire engine cab status monitoring and display system of claim 1, wherein: the serial port communication circuit comprises RS-232 serial port communication and a MAX232 chip, wherein T2IN and R2OUT are respectively connected with P3.1 and P3.2 of the singlechip to serve as serial data sending and receiving ports of the singlechip, R2IN and T2OUT are connected with a sending end and a receiving end of an RS-232 serial port of a computer, J1 is a serial port seat and is used for carrying OUT data transmission, so that TTL level sent by a TXD port of the singlechip is converted into RS-232 level through the MAX232 chip and then sent OUT from a 7-pin T2OUT of MAX232, data are transmitted to the computer through a 2-pin RXD end of the serial port seat, the computer receives the data, the computer sends the data to the singlechip through 3-way TXD of the serial port seat, the RXD end of the singlechip receives the data, and a drive coupling capacitor is arranged between VCC and the.
8. The fire engine cab status monitoring and display system of claim 1, wherein: the system adopts a USB power supply mode, a switch circuit is added in the circuit, a switch is pressed down, an indicator light is on, and the system is powered on; and the switch is pressed again, the indicator light is turned off, and the system loses power and comprises a three-terminal voltage stabilization integrated chip 7805 which provides stable direct-current voltage VCC with the value of +5V and the maximum current of 1.5A, a rectifier diode 1N4007 performs rectification, and capacitors C9 and C11 are arranged for filtering input and output ends.
9. The fire engine cab status monitoring and display system of claim 1, wherein: buzzer and LED lamp warning circuit include two-stage alarm circuit, wherein:
the secondary alarm circuit comprises an LED lamp; the primary alarm circuit comprises a buzzer.
10. The fire engine cab status monitoring and display system of claim 1, wherein: still include emergency braking circuit, procedure download circuit, reset circuit and crystal oscillator circuit, wherein the procedure download circuit includes: the P1.5 socket 1 pin MOSI of the singlechip represents the output signal; reset socket 5 pin RST, representing the reset terminal; p1.7 socket 7 pin SCK, representing a clock signal; p1.6 patch socket 7 pin MISO, representing an input signal; the single chip VCC and GND are respectively connected with pins 2, 4, 6, 8 and 10 of the socket, and represent a power supply and a ground wire; the reset circuit includes: RST of the single chip microcomputer is directly connected with VCC, RST is high level, and the system is reset; the crystal oscillator circuit comprises an oscillator circuit formed by an inverting amplifier, an oscillation source is added in a peripheral circuit, a quartz crystal is used as the oscillation source, XTAL1 and XTAL2 are used as the input end and the output end of the inverting amplifier, and two 30pf capacitors are externally connected to the two ends in parallel to form an oscillator formed by the inverting amplifier, the crystal oscillator and the capacitors so as to generate a clock signal.
Technical Field
The invention relates to the technical field of state monitoring and display, in particular to a state monitoring and display system for a cab of a fire engine.
Background
The continuous development of urbanization in China is accompanied with the continuous and rapid increase of high-rise buildings, so that a fire truck for fire extinguishment and rescue is more important, and the fire extinguishment, rescue and rescue of the high-rise buildings are completed. In the process of fire-fighting and rescue, once the fire truck breaks down or has an accident, the fire-fighting and rescue vehicle not only can injure surrounding personnel, but also can delay the whole fire-fighting and rescue task, and thus very serious personnel and economic losses can be caused certainly. Therefore, its safety reliability is absolutely not negligible. Whatever the machine, each action is executed, the machine has the maximum safety limit of the machine, and once the maximum safety limit is exceeded, certain equipment parts of the machine are damaged slightly, and a serious accident of machine destruction and human death is caused seriously. Because the structure of the fire engine is complex and the operation environment is uncertain, in order to ensure the normal and safe operation of the fire engine, all actions of the fire engine must be controlled to operate within the safe range.
In recent years, technologies such as electronic technology, sensor technology, and computers have been rapidly developed, and these technologies have now been applied to control systems of construction machines. For the fire fighting truck, the development is gradually carried out in the directions of maximization, multi-functionalization, intellectualization, safety, modularization, serialization, light weight and the like. In order to improve the safety, reliability and efficiency of the fire fighting truck, the real-time monitoring of the running state of the fire fighting truck is very slow. That is, the fire engine can only work under the reliable state monitoring control system, and the accident rate can be reduced, and the task that it needs to carry out can be accomplished safely and efficiently.
Disclosure of Invention
In order to overcome the problems in the prior art, the invention aims to provide a monitoring and displaying system for the state of a cab of a fire engine, which is characterized in that a single chip microcomputer is used as a microcontroller for system development, and software simulation is performed through a Proteus, so that the aims of saving development cost and shortening development period are fulfilled
The invention aims to provide a fire engine cab state monitoring and displaying system, which comprises a computer end, a cab front end display screen and a fire engine rear end control system, wherein the computer end is connected through a DTU data transmission line, the cab front end display screen is connected with the fire engine rear end control system through a serial port communication circuit, the fire engine cab state monitoring and displaying system adopts an MSC-51 series STC15F2K16S2 single chip microcomputer, and the fire engine cab state monitoring and displaying system is provided with: a plurality of sensor signal acquisition circuits, LCD liquid crystal display circuit, keyboard control circuit, bee calling organ and LED lamp warning circuit and serial communication circuit, a plurality of sensor signal acquisition circuits interconnect for gather the status information of fire engine, LCD liquid crystal display circuit sets up inside the fire engine driver's cabin, a final circuit for showing the status information of fire engine, keyboard control circuit with LCD liquid crystal display circuit connects for control passes through keyboard input control information, bee calling organ and LED lamp warning circuit establish ties or connect in parallel, when taking place carry out sound and/or light warning under the condition that the status information of fire engine needs to report to the police, serial communication circuit is used for monitoring and display system handles the information transfer of the display output of final data from the collection of signal.
Preferably, the sensor signal acquisition circuit is used for acquiring 4 signals of bucket loading, amplitude variation angle, lifting height and fire scene temperature, and the dynamic parameters to be monitored by the monitoring and display system include: the sensor signal acquisition circuit comprises a force measuring sensor, an inclination angle sensor, a rotary encoder, an angle sensor, a wind speed sensor, a smoke sensor, a temperature sensor and an ultrasonic sensor, wherein the force measuring sensor is an ST-27 cantilever beam type force measuring sensor, one end of the force measuring sensor is fixed, the other end of the force measuring sensor is loaded and can be pulled and pressed, the sensor outputs a voltage signal of 0-5V, the analog signal is required to be converted into digital quantity through an A/D conversion circuit and transmitted to a main controller for processing, and the installation position of the sensor is positioned between a bottom plate and an outer frame of the working platform; the inclination angle sensor is an TQG-S series high-precision one-dimensional inclination angle sensor for measuring angle signals in real time, the sensor comprises three signal wires, a red wire is connected with the positive electrode of a power supply, a black wire is grounded, a yellow wire is an output signal wire of an X axis, the inclination angle sensor outputs a 4-20mA current signal or a 1-5V voltage signal, an A/D conversion circuit converts an analog signal into a digital quantity to be transmitted to a main controller for processing, and the analog signal is installed on the outer side of a ladder frame telescopic arm; the rotary encoder is selected as an E6B2-CWZ1X500PPR incremental photoelectric encoder under an ohm dragon and used for measuring the height of the ladder frame operation, digital quantity signals are output by the rotary encoder and directly connected with a main controller for operation processing, the rotary encoder is installed on a bearing of a piston rod magnetic steel wheel, the magnetic steel wheel rotates when the piston rod moves, the encoder also rotates, the pulse number is finally calculated, a P2.0 pin of a single chip microcomputer is used for representing A-phase pulses output by the rotary encoder, the P2.1 pin is directly connected with an external interrupt INT0 of the main single chip microcomputer and is directly connected with a P3.4 pin of the main single chip microcomputer. (ii) a The angle sensor is selected to be a CK-1 angle sensor, the CK-1 angle sensor adopts an analog quantity output form, carries out A/D conversion on the analog quantity output form and then sends the analog quantity to the main controller, and the main controller can output the analog quantity and is arranged below the rotary table; the wind speed sensor is an HL-FSX1 integrated wind speed and direction sensor of a spark tester, and is output in various modes of 4-20mA current, 0-5V voltage, RS232, RS485 and TTL signals, and is arranged on a working platform to measure wind speed; the smoke sensor is an MQ-2 smoke sensor; the temperature sensor is a DS18B20 sensor, data transmission is carried out in a digital mode of a one-line bus, only one signal line is needed for collecting temperature signals, the temperature measurement range is-55-125 ℃, information is transmitted through a single-line interface, a DQ end of the temperature sensor is an output signal line and is directly connected with a P2.7 pin of the single chip microcomputer, VCC is connected with a 5V power supply for power supply, and GND is grounded; the ultrasonic sensor is a piezoelectric ultrasonic sensor.
Preferably, the force of the ST-27 cantilever beam type load cell acts on the free end, two strain gauges are respectively adhered to the upper surface and the lower surface near the fixed end of the beam and connected into a bridge circuit, and when the load increases, the sensitive flashover resistance R2 is R3, and the change quantity of the sensitive flashover resistance increases along with the increase of the load, so that the output △ U is output 01And finally, an A/D conversion circuit is needed to convert the analog electrical signal into a digital electrical signal and input the digital electrical signal to a single chip microcomputer to complete measurement of the bucket load, the ST-27 cantilever beam type force transducer is fixed between the outer frame of the working platform and the bearing plane, the supporting points are close to the periphery and are uniformly distributed, under the action of gravity, an elastic body of the transducer generates elastic deformation, a resistance strain gage adhered to the surface is deformed to change the resistance value of the resistance strain gage, and the A/D conversion circuit can convert the change of the resistance value into a corresponding digital electrical signal through corresponding measurement.
Preferably, the analog-to-digital converter further comprises an A/D conversion circuit for carrying out A/D conversion on two signals at a bucket loading angle and a variable amplitude angle, wherein an ADC0832 conversion chip is arranged in the A/D conversion circuit, a 5V power supply is adopted for supplying power, the input voltage is between 0 and 5V, the working frequency is 250KHz, the conversion time is 32us, the power consumption is usually only 15MW, the input level and the output level of the analog-to-digital converter are compatible with the TTL/CMOS level, wherein the low level of a chip selection enabling signal is effective, a P1.4 pin of a single chip is connected, CH0 and CH1 are respectively an
Preferably, the LCD liquid crystal display circuit comprises an LCD12864 liquid crystal display, the working voltage is 3-5.5V, the working temperature is 0-60 ℃, a serial and parallel communication mode is supported, the liquid crystal display of the final system consists of a monitoring startup interface, a data monitoring interface and a parameter
Preferably, the keyboard control circuit comprises two groups of keys, and the first group of keys is responsible for setting the content displayed on the LCD12864 liquid crystal display: k1 is used for making the data monitoring interface on the LCD enter the interface for setting the rated value of the parameter, once entering the interface for setting the rated value of the parameter, the rated value of the parameter to be measured can be set, K2 is used for increasing the rated value, K3 is used for reducing the rated value, after setting, the key K4 makes the interface for setting the rated value of the parameter return to the interface for monitoring the data, and the parameter to be measured is monitored in real time; the other group of keys controls the telescopic action of the aerial ladder fire truck: pressing k1, the aerial ladder fire truck ladder frame begins to extend; pressing k2 to stop the action; k3 is the switching of the expansion of the ladder frame, press k3, the movement of the ladder frame changes from expansion to contraction, press k3, the movement changes from contraction to expansion; k4, the expansion and contraction speed is increased; k5 reduces the telescoping speed.
Preferably, the serial port communication circuit comprises an RS-232 serial port communication and a MAX232 chip, T2IN and R2OUT are respectively connected to P3.1 and P3.2 of the singlechip as serial data transmitting and receiving ports of the singlechip, R2IN and T2OUT are connected to a transmitting end and a receiving end of an RS-232 serial port of a computer, J1 is a serial port seat for data transmission, so that a TTL level sent by a TXD port of the singlechip is converted into an RS-232 level by the MAX232 chip, and then sent OUT from a 7-pin T2OUT of the MAX232, and passes through a 2-pin RXD end of the serial port seat to transmit data to the computer, the computer receives the data, the computer sends the data to the singlechip through 3-way traffic of the serial port seat, the RXD end of the singlechip receives the data, and a drive coupling capacitor is arranged between VCC and the ground.
Preferably, the system also comprises a power supply and voltage stabilizing circuit, the system adopts a USB power supply mode, a switch circuit is added in the circuit, a switch is pressed, an indicator light is on, and the system is powered on; and the switch is pressed again, the indicator light is turned off, and the system loses power and comprises a three-terminal voltage stabilization integrated
Preferably, the buzzer and LED lamp alarm circuit comprises a two-stage alarm circuit, wherein:
the secondary alarm circuit comprises an LED lamp; the primary alarm circuit comprises a buzzer.
Preferably, the emergency braking circuit, the program downloading circuit, the reset circuit and the crystal oscillator circuit are further included, wherein the program downloading circuit comprises: the P1.5
The invention has the beneficial effects that:
1. the system uses the single chip as a microcontroller to carry out system development, and carries out software simulation through the Proteus so as to achieve the purposes of saving development cost and shortening development period. The dynamic state of the fire engine is mastered in real time so as to take corresponding measures in time, the rescue efficiency is improved, and firefighters are well protected.
2. The display screen gathers fire engine control and starts behind the fire engine, temperature, pressure, the angle relevant parameter to give the fire engine driver's cabin through serial ports communication technology with data transmission and carry out the synchronous monitoring, form a complete, comprehensive control display control system. The display screen of the cab of the fire engine synchronously displays the related content of the rear display screen of the fire engine, and the multi-control function of the single engine is realized. Sit in the driver's cabin and can control fire engine rear end display system, fire engine rear end display system can control the driver's cabin. Work is carried out in step, still can pass through computer remote operation, makes rescue work more high-efficient, and speed is faster, and the fire fighter can directly control the fire engine in the driver's cabin if meet emergency and need not get off. The state monitoring has necessary self-diagnosis capability, self-diagnoses certain faults of the machine such as a display, a sensor, a memory, a power supply and the like, can provide a handling processing scheme, has a recording function mainly for recording the running condition and the overload condition of the fire-fighting truck, and can analyze and process the data information in time. Once an accident occurs, the search for the accident reason is facilitated.
Drawings
FIG. 1 is a schematic diagram of a fire engine according to an embodiment of the present invention;
FIG. 2 is a block diagram of a fire truck cab condition monitoring and display system according to an embodiment of the present invention;
FIG. 3 is a general block diagram of the status monitoring and display hardware of the cab of the fire engine according to an embodiment of the invention;
FIG. 4 is a bridge circuit diagram for measuring bucket loading according to an embodiment of the present invention;
FIG. 5 is a schematic diagram of an A/D conversion circuit according to an embodiment of the present invention;
FIG. 6 is a waveform diagram of an encoder in accordance with an embodiment of the present invention;
FIG. 7 is a circuit diagram of an encoder according to an embodiment of the present invention;
FIG. 8 is a sensor and peripheral circuitry for ambient temperature measurement according to an embodiment of the present invention;
FIG. 9 is a circuit diagram of a liquid crystal display according to an embodiment of the present invention;
FIG. 10 is a circuit diagram of a serial port communication circuit of a MAX232 chip according to an embodiment of the present invention;
FIG. 11 is a power supply circuit diagram according to an embodiment of the invention;
FIG. 12 is a circuit diagram of an alarm signal prompt according to an embodiment of the present invention;
FIG. 13 is a schematic diagram of a buzzer warning circuit in accordance with an embodiment of the present invention;
FIG. 14 is a schematic diagram of an emergency braking circuit according to an embodiment of the present invention;
FIG. 15 is a schematic diagram of a download interface circuit according to an embodiment of the present invention;
FIG. 16 is a schematic diagram of a reset circuit according to an embodiment of the present invention;
FIG. 17 is a schematic diagram of a crystal oscillator circuit according to an embodiment of the present invention;
Detailed Description
The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings, but the present invention is not limited thereto.
In this embodiment, the research object takes an aerial ladder fire truck as an example, and as shown in fig. 1, the aerial ladder fire truck comprises a vehicle chassis, a telescopic mechanism, a luffing mechanism, a slewing mechanism, a working bucket and a supporting mechanism. The part above the swing mechanism is called boarding and the part of the vehicle chassis below the swing mechanism (including the legs) is called disembarking.
In order to determine the stability and reliability of the aerial ladder fire truck during operation, the system needs to monitor the changes of dynamic parameters such as the load of a working bucket, the rotation angle of a rotary table, the load of an arm support, the amplitude variation angle of the arm support, the working amplitude of the arm support, the lifting height of the arm support, the wind speed and the like.
Furthermore, at the fire scene, the smoke inside the fire scene contains a large amount of harmful substances, which are roughly classified into three categories: harmful gases, smoke and heat. Most of the smoke dust is carbon-containing substances, and the hydrogen chloride gas covered on the surface of the fire scene can increase the concentration of toxic substances of the smoke dust, thereby causing great damage to the respiratory system of people; when the heat of fire field combustion is too high, the respiratory tract is also burnt by heat. Therefore, monitoring of smoke and temperature in the field is also essential. In the ladder frame operation process, the work fill can not avoid meeting some barriers, in order to prevent aerial ladder fire engine work fill and barrier from colliding each other, causes the damage of work fill or other equipment, leads to whole car to overturn even, must monitor the distance that the barrier apart from the work fill to guarantee that the work fill can automatic stop ladder frame work under the condition that meets the barrier, prevents the emergence of collision.
Therefore, the dynamic parameters to be monitored by the system are: bucket loading capacity, amplitude variation angle, lifting height, rotation angle, wind speed, surrounding environment smoke, surrounding environment temperature, distance from an obstacle and the like.
The force sensor is an ST-27 cantilever beam type force sensor, one end of the force sensor is fixed, the other end of the force sensor is loaded, and the force sensor can be pulled and pressed. The sensor outputs a voltage signal of 0-5V, the analog signal is converted into digital quantity through an A/D conversion circuit and is transmitted to a main controller for processing, and the mounting position of the sensor is positioned between a bottom plate and an outer frame of the working platform.
The inclination angle sensor is used for controlling the safe range of the amplitude variation range of the ladder frame within a certain range in the running process of the fire fighting truck, so that the rollover accident is prevented. An TQG-S series high-precision one-dimensional inclination angle sensor is selected to measure angle signals in real time, the sensor has three signal wires in total, a red wire is connected with the anode of a power supply, a black wire is grounded, and a yellow wire is an output signal wire of an X axis. The sensor outputs a 4-20mA current signal or a 1-5V voltage signal, and the analog signal needs to be converted into a digital quantity through an A/D conversion circuit and transmitted to a main controller for processing, and the digital quantity is installed on the outer side of the ladder frame telescopic arm.
Selection of rotary encoder: in the working process of the aerial ladder fire truck, different vehicle types have the specified maximum working height, the aerial ladder fire truck must work within the specified range to ensure the safety of vehicles and personnel, before the working height of a calculator, the total telescopic length of a ladder frame is obtained, and then the final working height is obtained through the relation between the total telescopic length and the amplitude variation angle. The photoelectric encoder is selected to measure the height of the ladder frame. According to the contrast, the E6B2-CWZ1X500PPR incremental photoelectric encoder under the ohm of the sensor manufacturer which is mainstream at present is selected, the working principle of the incremental photoelectric encoder is to convert the mechanical displacement into the digital quantity of the encoder finally, and then the digital quantity is counted by a counter of a monitoring system. The photoelectric encoder outputs digital quantity signals, can be directly connected with a main controller to perform operation processing, is arranged on a bearing of a magnetic steel wheel of a piston rod, and when the piston rod moves, the magnetic steel wheel rotates, the encoder also rotates along with the magnetic steel wheel, and finally the pulse number is calculated.
Selection of angle sensor: in the operation process of the aerial ladder fire truck, the variable angle of the ladder frame has the self variable amplitude range and is different according to different vehicle types. The angle sensor of the embodiment selects a CK-1 angle sensor to measure the amplitude variation angle. The CK-1 angle sensor selects an intelligent magnetic sensitive element, converts signals such as mechanical rotation and angular displacement into electric signals, belongs to non-contact measurement, and can measure absolute angular position within a range of 360 degrees. The sensor can provide a plurality of output forms such as analog quantity, SPI serial protocol, PWM pulse width modulation wave and the like, has higher sensitivity, resolution ratio and cost performance, has good temperature stability, and is simultaneously suitable for severe environments such as water, oil, steam, dust and the like. The sensor adopts an analog quantity output form, carries out A/D conversion on the sensor and then sends the converted sensor to the main controller, and the sensor can output analog quantity and is arranged below the rotary table.
Selection of a wind speed sensor: in the weather of open wind, if the wind power is 5 grades, the wind speed is 20km/h, the aerial ladder can normally work, if the wind power reaches 6 grades, the aerial ladder frame can only be lifted to 2/3 with the maximum working height at most, and if the wind power is more than 6 grades, the aerial ladder fire truck should stop operating so as to avoid danger. In the embodiment, an HL-FSX1 integrated wind speed and direction sensor of the spark tester is selected, and the wind speed and direction sensor is installed on a working platform to measure the wind speed through outputting in various modes of 4-20mA current, 0-5V voltage, RS232, RS485 and TTL signals.
The smoke sensor is selected, and the MQ-2 smoke sensor is selected in the embodiment, so that the method is suitable for detection of liquefied gas, methane, propane, butane, hydrogen, alcohol and smoke.
Selection of temperature sensor: the field fire is too high, so that the body of the trapped person is seriously injured, the ambient temperature needs to be monitored in real time, and the DS18B20 sensor is selected by the system.
Selection of ultrasonic sensors: for the urgent danger avoidance of surrounding obstacles, a piezoelectric ultrasonic sensor is adopted in the system, the piezoelectric ultrasonic sensor is a reversible sensor, a pulse electric signal applied by a piezoelectric crystal is converted into mechanical oscillation, ultrasonic waves are generated when resonance is achieved, and in the same way, when a resonance board receives ultrasonic waves, the mechanical signal is converted into an electric signal, so that the piezoelectric ultrasonic sensor is suitable for being transmitted in the air.
The overall design of the system should have the following functions:
the real-time monitoring function is as follows: various parameters needing to be monitored in the running process of the fire fighting truck are determined, so that the system firstly needs to complete the real-time monitoring function of the measured parameters.
A parameter setting function: as the parameter rated values of different fire engines are different from each other, in order to improve the universality and the applicability of the system, the modification of the rated values of the parameters is realized through key setting
And (3) real-time display function: in order to enable an operator to monitor working parameter values of the fire fighting truck in real time under the operation state, a proper display is required to be selected to display the parameter values, and each operation parameter value of the fire fighting truck can be displayed in real time in a numerical mode by adopting a nixie tube or an LCD display;
alarm and power-off protection functions: and when the system receives the running state of the fire fighting truck, corresponding treatment is needed. If the parameter value of the state when the fire engine runs reaches a certain value, the system must send out an alarm and early warning. Once the value of the condition parameter exceeds its maximum allowable rating, the system must be automatically powered down to allow the operator to stop the vehicle for inspection
Data storage function: recording actual measured values of all parameters of the fire fighting truck in the operation process and corresponding moments of the values, and using the actual measured values as historical data of the fire fighting truck, so that the subsequent fault diagnosis and maintenance of the fire fighting truck are facilitated;
self-diagnostic and recording functions: the state monitoring has necessary self-diagnosis capability, self-diagnoses certain faults of the machine such as a display, a sensor, a memory, a power supply and the like, can provide a handling processing scheme, and has a recording function mainly for recording the operation state and the overload state of the aerial ladder fire truck and analyzing and processing the data information in time. Once an accident occurs, the search for the accident reason is facilitated.
The whole monitoring system adopts a single chip microcomputer solution scheme:
the single chip microcomputer is widely applied due to high performance ratio and high reliability, the monitoring system adopts the high-performance eight-bit or sixteen-bit single chip microcomputer as a core, the signals collected by all the sensors of the system are processed through an A/D conversion circuit, and the running state information of the aerial ladder fire truck, including characters or graphs, is simply displayed by using a nixie tube or provided for an operator by using an LCD. And the output of the relay is controlled by using the data output interface and the driving circuit, and data is transmitted to an upper computer for synchronous monitoring through a serial port communication technology, so that a complete and comprehensive monitoring system is formed.
Referring to fig. 2, the rear display screen of the fire fighting truck collects the relevant parameters of the fire fighting truck such as control start, temperature, pressure and angle, and transmits the data to the cab of the fire fighting truck for synchronous monitoring through the serial port communication technology, so as to form a complete and comprehensive monitoring and display system. The display screen of the cab of the fire engine synchronously displays the related content of the rear display screen of the fire engine, and the multi-control function of the single engine is realized. Sit in the driver's cabin and can control fire engine rear end display system, fire engine rear end display system can control the driver's cabin. Work is carried out in step, still can pass through computer remote operation, makes rescue work more high-efficient, and speed is faster, and the fire fighter can directly control the fire engine in the driver's cabin if meet emergency and need not get off.
Hardware structure design of the system:
as shown in fig. 3, the present embodiment selects an STC15F2K16S2 single chip microcomputer of the MSC-51 series, which includes: the device comprises a sensor signal acquisition circuit, an LCD (liquid crystal display) circuit, a keyboard control circuit, a buzzer, an LED lamp alarm circuit, a serial port communication circuit and the like. The main circuits can complete a series of functions from signal acquisition and processing to final data display and output of the monitoring system.
Firstly, a sensor signal acquisition circuit: the system collects 4 signals of bucket loading, amplitude variation angle, lifting height and fire field temperature.
1. The load measurement of the working bucket adopts an ST-27 cantilever beam type force transducer, the force of the transducer acts on the free end, two strain gauges are respectively adhered to the upper surface and the lower surface near the fixed end of the beam, the upper surface and the lower surface are connected into a bridge circuit as shown in figure 4, when the load is increased, the sensitive flashover resistance R2 is R3, the change amount is increased, and the output is △ U 01And finally, the analog electric signal is converted into a digital electric signal by an A/D conversion circuit and is input to the singlechip to complete the measurement of the bucket load. Therefore, the sensor is fixed between the outer frame of the working platform and the bearing plane, and the supporting points are as close to the periphery as possible and are uniformly distributed. When a person (including a fireman, a victim and some important articles) starts to stand in the working bucket, under the action of gravity, the elastic body of the sensor generates elastic deformation, so that the resistance strain gauge adhered to the surface also generates deformation to change the resistance value of the resistance strain gauge, and then the A/D conversion circuit converts the change of the resistance value into a corresponding digital electric signal through corresponding measurement.
2. And (3) measuring the amplitude variation angle: the system adopts TQG-S series high-precision one-dimensional inclination angle sensors to measure the amplitude variation angle of the aerial ladder fire truck, utilizes a potentiometer with 500 ohms to simulate the change of amplitude variation angle signals, represents the real-time change of the amplitude variation angle through the change of the resistance value of the potentiometer, and finally converts the analog signals into digital signals through the conversion of an A/D conversion circuit and transmits the digital signals to a singlechip for monitoring. Three signal wires of the potentiometer are connected in the same way, one is grounded, the other is connected with the anode of the power supply, and the other signal wire is used as a signal output wire.
3. An A/D conversion circuit: A/D conversion is needed to be carried out on two paths of signals with bucket loading and amplitude changing angles, an ADC0832 conversion chip is selected, 8-bit resolution and double channels are provided, as shown in figure 5, when a 5V power supply supplies power, the input voltage is 0-5V, the working frequency is 250KHz, the conversion time is 32us, the power consumption is usually only 15MW, the input level and the output level of the ADC0832 conversion chip can be compatible with TTL/CMOS levels, the temperature of an industrial grade chip is-40-85 ℃, and the temperature of a commercial grade chip is 0-70 ℃. Wherein the content of the first and second substances,
4. And (3) measuring the lifting height: the working principle of the measuring device is that firstly, a displacement signal is converted into a periodic electric signal, then the electric signal is converted into counting pulses, and the size of the displacement is represented by the number of the pulses. Therefore, when the piston rod of the ladder frame telescopic oil cylinder begins to extend and retract, the encoder also begins to rotate, two paths of digital pulse signals are generated, the digital pulse signals are represented by A and B, and the phase difference is 90 degrees. In the normal rotation, A advances by B90 degrees, and in the reverse rotation, B advances by A90 degrees. And one phase of Z-phase pulse signal representing reference zero position, the number of pulses and displacement clock are in proportional relation. The system adopts another STC15F2K16S2 singlechip to replace the photoelectric encoder, and uses the P2.0 pin of the singlechip to represent the A-phase pulse output by the photoelectric encoder, the pin is directly connected with the external interrupt INT0 of the main singlechip, the P2.1 pin represents the B-phase pulse output by the main singlechip, and is directly connected with the P3.4 pin of the main singlechip. INT0 is first set to a falling edge trigger, when the A phase pulse starts to trigger an interrupt, the master chip generates an external interrupt, the system will execute an interrupt handler, and then determine whether the B phase pulse is high or low. If the level is low, the encoder forwards and counts by 1; if high, the encoder will invert, subtracting 1 count. The system finally completes the measurement of the telescopic length of the ladder frame through the product calculation of the pulse number by continuously triggering interruption through an effective pulse signal, and then converts the telescopic length into the lifting height through a geometric relationship. The encoder waveform diagram is shown in fig. 6. Fig. 7 shows a circuit diagram of the encoder.
5. The measurement of ambient temperature adopts DS18B20 temperature sensor, as shown in FIG. 8, adopt the digital mode of a ray of bus to carry out data transmission, only need a signal line to gather temperature signal, the temperature measurement range is between-55 ~ 125 degrees centigrade to transmit information through the single-wire interface, its DQ end is the output signal line, directly link to each other with the P2.7 pin of singlechip, only need this connecting wire just can accomplish the sending and receiving of temperature data, VCC connects the 5V power and supplies power, GND ground connection.
Second, liquid crystal display circuit
The system is designed in such a way that the upper computer and the lower computer simultaneously monitor the running state of the aerial ladder, the lower computer mainly displays the actual value and the rated value of the state parameter, and the upper computer displays the parameter change curve. Considering the cost, the LCD12864 LCD with a moderate amount of information is selected in the present embodiment, the LCD12864 LCD is a liquid crystal display driven by a backlight and a 5V voltage, and includes 8192 dot matrixes of 16 × 16 and character sets of 128 ASCII codes of 16 × 8, and finally, not only the chinese characters of 16 × 16 dot matrixes of 8 × 4 lines can be displayed on the liquid crystal screen, but also the graphics can be displayed. The working voltage is 3-5.5V, the working temperature is 0-60 ℃, and the serial and parallel communication modes are supported. The LCD of the final system is composed of a monitoring startup interface, a data monitoring interface and a parameter
DB0-DB 7: a 3-state data line;
and RS: a data/command selection terminal for representing the display data of DB0-DB7 port when RS is H, and representing the display command data of DB0-DB7 port when RS is L;
R/W: and a read/write select terminal. When R/W is equal to H and E is equal to H, the data is read into DB0-
e: an enable signal; when R/W is equal to L, the falling edge of the E signal latches the ports DB0-
CS1, CS 2: and chip selection signals. When CS1 is at high level, selecting the right half screen signal of the chip; when CS2 is at high level, selecting the left half screen signal of the chip;
VDD: supply voltage, 5V;
VSS: power ground, 0V;
v0: liquid crystal contrast adjustment voltage;
VOUT: LCD drive negative voltage, -10V;
RET: the low level is effective;
LED +: LED backlight power supply anode, DC + 5V;
LED-: LED backlight power supply cathode, DC 0V;
an interface circuit of the LCD and the single chip is shown in fig. 9. V0 is used to adjust the contrast of liquid crystal, the contrast can not be too high or too low, therefore, it needs to connect a 10K potentiometer to adjust the voltage, the two ends of the potentiometer are connected with VDD and VSS, the DB0-DB7 ends are connected with P0.0-P0.7 pins of the single chip respectively. CS1, CS2, RS and R/W, E are connected to P2.0-P2.4 pins of the single chip microcomputer, and negative pressure is output from a VOUT port and is transmitted to a V0 port through a 10K potentiometer.
Third, key control circuit
This system has designed two sets of buttons altogether, and the function of first group button is responsible for setting up the content that shows on LCD12864 LCD: the function of the K1 is to enable a data monitoring interface on the liquid crystal display to enter a parameter rating setting interface, and once the interface enters the parameter rating setting interface, the rating of the measured parameter can be set. K2 is used to increase its rating and K3 is used to decrease its rating. After the setting is finished, a key K4 is needed, the parameter rated value setting interface returns to the data monitoring interface, and the measured parameter is monitored in real time. The other group of keys controls the telescopic action of the aerial ladder fire truck: pressing k1, the aerial ladder fire truck ladder frame begins to extend; pressing k2 to stop the action; k3 is the switching of the expansion of the ladder frame, press k3, the movement of the ladder frame changes from expansion to contraction, press k3, the movement changes from contraction to expansion; the speed of the aerial ladder fire truck is not constant when the aerial ladder fire truck is stretched, so that the speed of the aerial ladder fire truck needs to be controlled in real time, and k4 is used for accelerating the stretching speed; k5 reduces the telescoping speed.
Four, serial port communication circuit
In order to know more information of the detected parameters of the aerial ladder fire truck in time and record and store the information, an upper computer needs to be developed to synchronously monitor the aerial ladder fire truck, and data transmission, including data sending and receiving, between the upper computer and a lower computer needs to be completed. In this embodiment, RS-232 serial communication and a MAX232 chip are selected, the MAX232 chip is a single power level conversion chip specially designed and produced for RS-232 standard serial ports, a 5V single power supply mode is used, if a capacitor is externally connected, conversion between TTL level and RS-232 level can be completed, a hardware interface is simple, price is relatively low, and a chip interface circuit diagram is shown in fig. 10. T2IN and R2OUT are respectively connected with P3.1 and P3.2 of the singlechip, which are serial data transmitting and receiving ports of the singlechip. And R2IN and T2OUT are connected to a sending end and a receiving end of an RS-232 serial port of a computer. J1 is a serial port seat for data transmission, so that the TTL level sent from the TXD port of the single chip microcomputer is converted into RS-232 level by the MAX232 chip, then the RS-232 level is sent from the 7-pin T2OUT of the MAX232 chip, the data is transmitted to the computer through the 2-pin RXD end of the serial port seat, the computer receives the data, and similarly, the computer sends the data to the single chip microcomputer through the 3-pin TXD of the serial port seat, and the RXD end of the single chip microcomputer receives the data. In practical application, since the components are very sensitive to the noise of the power supply, a driving and coupling capacitor is added between VCC and ground.
Fifthly, power supply and voltage stabilizing circuit
The system adopts a USB power supply mode, the system can start working only by connecting a USB port on hardware into a computer, the computer outputs 0-5V voltage, the working voltage range conforming to the singlechip is that a switch circuit is added into the circuit, a switch is pressed, an indicator light is on, and the system is electrified; and pressing the switch again to turn off the indicator light and power off the system. Since the performance of some devices is greatly affected by the voltage, the fluctuation of the voltage may cause the performance of the devices to be unstable or cause errors in parameter values. Therefore, a direct current stabilized power supply circuit outputting positive 5V is introduced to increase the stability of the system. And selecting a three-terminal voltage stabilization integrated
Sixth, alarm circuit of system
During the operation of the aerial ladder fire truck, when the measured parameter value approaches or reaches the rated value, the system must give an alarm to remind the driver to pay attention, and take corresponding measures, and the system designs two-stage alarm:
secondary alarming: when the measured parameters reach 95% of the rated values, the system starts early warning, indicator lamps of all the parameters start to flicker, and a driver needs to pay attention to the qualitative change;
primary alarm: when the measured parameter value exceeds the rated value, the system gives an alarm, at the moment, the indicator lamps of all the parameters do not flicker, but keep the red color unchanged, the buzzer also starts to sound, the relay is automatically closed, the aerial ladder fire truck stops working, and the driver can find out the reason immediately. The hardware circuit of this part is shown in fig. 12 and 13.
Seven, emergency braking circuit
The main actions of the aerial ladder fire truck comprise ladder frame expansion, amplitude variation and rotation, and when different actions exceed the limit states in the running process, emergency braking is required to ensure the machine. Therefore, an emergency braking circuit is designed for the monitoring system of the aerial ladder fire truck to prevent the damage of various equipment parts of the vehicle. The present system is exemplified by a relay circuit that operates in a telescopic manner, and a circuit diagram is shown in fig. 14.
Eight, program downloading circuit
The system selects an ISP downloading circuit, programs are directly programmed and written recently through an ISP socket, and the chip is not taken down and then put on a special programming device for programming. The welded ISP downloader and the single chip microcomputer are connected together by using a DIP10 socket, and an interface circuit is shown in figure 15. The P1.5
Nine, reset circuit and crystal oscillator circuit
1. A reset circuit: the single chip microcomputer can be re-executed under the condition that the program runs away and the operator cannot normally monitor the information of the measured parameters, so that the system returns to a normal monitoring state. In this embodiment, a key reset mode is adopted, and a reset circuit is shown in fig. 16. The reset pin RST of the single chip microcomputer is effective in high level, namely the system is reset in high level, and the system works normally in low level. When the key is pressed, the capacitor is short-circuited and starts to discharge. RST of the single chip microcomputer is directly connected with VCC, RST is high level, and the system is reset. When the key is released, the power supply starts to charge the capacitor again until the voltage on the resistor is close to 0 after the capacitor is charged, the voltage of the RST is the voltage of the resistor and is reduced to low level, and the system starts to execute the program again and works normally.
2. A crystal oscillator circuit: the STC15F2K16S2 single chip microcomputer is internally provided with an oscillation circuit formed by an inverting amplifier, a clock signal can be generated and sent to the inside of the single chip microcomputer only by adding an oscillation source in a peripheral circuit, a quartz crystal is selected as the oscillation source, XTAL1 and XTAL2 are input and output ends of a reverse amplifier, two capacitors are externally connected to the two ends in parallel to assist oscillation starting of the oscillation source and fine adjustment of frequency, and the typical value is 30 pf. Thus, an oscillator is formed by the inverting amplifier, the crystal oscillator and the capacitor to generate the clock signal. Different crystal oscillators have different machine periods, the higher the clock frequency is, the higher the working speed of the single chip microcomputer is, and the crystal oscillator is selected to be 11.0592MHz in the embodiment. The crystal oscillator circuit is shown in fig. 17.
In this embodiment:
1. the system uses the single chip as a microcontroller to carry out system development, and carries out software simulation through the Proteus so as to achieve the purposes of saving development cost and shortening development period. The dynamic state of the fire engine is mastered in real time so as to take corresponding measures in time, the rescue efficiency is improved, and firefighters are well protected.
2. The display screen gathers fire engine control and starts behind the fire engine, temperature, pressure, the angle relevant parameter to give the fire engine driver's cabin through serial ports communication technology with data transmission and carry out the synchronous monitoring, form a complete, comprehensive control display control system. The display screen of the cab of the fire engine synchronously displays the related content of the rear display screen of the fire engine, and the multi-control function of the single engine is realized. Sit in the driver's cabin and can control fire engine rear end display system, fire engine rear end display system can control the driver's cabin. Work is carried out in step, still can pass through computer remote operation, makes rescue work more high-efficient, and speed is faster, and the fire fighter can directly control the fire engine in the driver's cabin if meet emergency and need not get off. The state monitoring has necessary self-diagnosis capability, self-diagnoses certain faults of the machine such as a display, a sensor, a memory, a power supply and the like, can provide a handling processing scheme, has a recording function mainly for recording the running condition and the overload condition of the fire-fighting truck, and can analyze and process the data information in time. Once an accident occurs, the search for the accident reason is facilitated.
The technical solutions provided by the embodiments of the present invention are described in detail above, and the principles and embodiments of the present invention are explained herein by using specific examples, and the descriptions of the embodiments are only used to help understanding the principles of the embodiments of the present invention; meanwhile, the detailed description and the application scope of the embodiments according to the present invention may be changed by those skilled in the art, and in summary, the present disclosure should not be construed as limiting the present invention.
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