Intelligent safety warning system
The intelligent safety warning system, which integrates vehicle information collection, communication, and projection angle detection modules, addresses the shortcomings of existing warning methods, enables rapid deployment and clear warnings in complex environments, and reduces the risk of secondary accidents.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-10
AI Technical Summary
Existing warning methods for road enforcement and construction vehicles suffer from drawbacks such as time-consuming deployment, difficulty in adjusting the warning range and shape, insufficient visibility in low-visibility environments, and a lack of real-time perception and tiered linkage of oncoming vehicle status, leading to an increased risk of secondary accidents.
It adopts a vehicle-mounted, remotely controllable laser warning system, combined with graded linkage sound and light warnings based on oncoming vehicle perception. Through projection angle detection and configurable warning area parameters, it achieves adaptive shaping of the warning area. It integrates vehicle information acquisition module, communication module, projection angle detection module and intelligent control module to ensure clear and continuous warning boundaries and enhance early warning in complex environments.
It enables rapid deployment of clear and continuous warnings in complex low-visibility environments, reduces the risk of secondary accidents, and provides more time for detection, braking, and lane change.
Smart Images
Figure CN121822294A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of rear warning systems for road traffic enforcement vehicles and road construction vehicles, and specifically relates to an intelligent safety warning system. Background Technology
[0002] Current road enforcement, accident handling, and maintenance operations largely rely on reflective cones, signs, and flashing lights for temporary closures and warnings. However, these methods generally suffer from problems such as time-consuming deployment, the need for personnel to enter traffic flow areas at close range, and insufficient visibility in low-visibility environments such as curves, slopes, nighttime, and rain / fog. Furthermore, the warning range and pattern are difficult to adjust quickly according to the number of lanes and the working distance, easily resulting in "discontinuous warnings" or "unclear warning boundaries," leading to delayed detection by vehicles behind, insufficient braking and lane-changing reaction time, and thus increasing the risk of secondary accidents. At the same time, existing audible and visual warnings are mostly fixed modes, lacking real-time perception and graded linkage of the distance and speed of vehicles behind, making it difficult to proactively increase the warning intensity when vehicles approach or intrude.
[0003] Therefore, there is an urgent need for an intelligent safety warning system that can be quickly deployed on vehicles, remotely controlled, adaptively outputting warnings based on the status of approaching vehicles and environmental conditions, and forming clearly visible warning boundaries. Summary of the Invention
[0004] In view of this, the present invention provides an intelligent safety warning system, which aims to combine a vehicle-mounted, remotely controllable laser warning area with a vehicle-sensing, graded, and linked audio-visual warning, and to achieve adaptive shaping of the warning area boundary through projection angle detection calibration and configurable warning area parameters. This enables rapid deployment, clear and continuous boundaries, and enhanced early warning in complex low-visibility environments, and significantly reduces the risk of secondary accidents.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] An intelligent safety warning system includes:
[0007] The vehicle information acquisition module is used to acquire information about approaching vehicles and output corresponding approaching vehicle detection signals to the intelligent control module.
[0008] The communication module is used to establish a wireless communication connection with the mobile terminal and to output configuration parameters to the intelligent control module through the mobile terminal and the communication module.
[0009] The projection angle detection module is used to obtain the attitude angle of the laser matrix projection component and output an angle feedback signal to the intelligent control module.
[0010] The intelligent control module determines the warning area on the ground based on configuration parameters and calibrates the actual projection angle of the laser matrix projection component based on the angle feedback signal. Once calibration is complete, the intelligent control module issues a warning control signal to control the laser matrix projection component to form a warning pattern within the warning area. When it receives a vehicle detection signal from the vehicle information acquisition module, the intelligent control module sends a working signal to the external warning lights and sirens via the sound and light alarm linkage interface, controlling the external warning lights and sirens to start working.
[0011] The laser matrix projection assembly includes a laser light control unit, a laser light driving unit, a laser light source, and an optical shaping assembly. The laser light control unit is electrically connected to the intelligent control module to receive warning control signals and generate cascaded control data. The laser light driving unit is electrically connected to the laser light control unit to drive the laser light source with constant voltage and current and perform PWM dimming according to the cascaded control data. The optical shaping assembly is disposed on the light emission path of the laser light source to array and shape the laser light, forming the warning pattern on the ground.
[0012] The intelligent safety warning system is powered by the vehicle's power supply for normal operation.
[0013] Preferably, the configuration parameters include the horizontal projection distance s of the laser light source, the preset height h of the laser light source, and the number of lanes n.
[0014] Preferably, the projection angle detection module includes a digital angle sensor, which is connected to the intelligent control module via a TTL UART serial port to output the actual projection angle ∠β of the laser light source as the angle feedback signal.
[0015] Preferably, the intelligent control module has an internal preset configuration rule, which determines the width w of the warning area based on the number of lanes n, and the length of the warning area is the horizontal projection distance s of the laser light source;
[0016] Furthermore, the configuration rules determine the theoretical projection angle ∠α of the laser source based on the horizontal projection distance s and the preset height h of the laser source in the configuration parameters.
[0017] The intelligent control module also has a preset first judgment rule, which includes an angle error threshold. When the theoretical projection angle ∠α of the laser source is equal to the actual projection angle ∠β, or when the difference between the theoretical projection angle ∠α and the actual projection angle ∠β does not exceed the angle error threshold, the first judgment rule determines that the actual projection angle ∠β has been calibrated. At this time, the intelligent control module issues a warning control signal, controls the laser matrix projection component to output laser light and form a warning pattern in the warning area. When the difference between the theoretical projection angle ∠α and the actual projection angle ∠β of the laser source exceeds the angle error threshold, the first judgment rule determines that the actual projection angle ∠β needs to be calibrated. At this time, the intelligent control module sends a calibration signal to the mobile terminal through the communication module. After receiving the calibration signal, the mobile terminal displays the calibration information.
[0018] Preferably, the vehicle information acquisition module includes a millimeter-wave radar, which is connected to the intelligent control module via a serial communication interface. After acquiring detection data of the distance and speed of the approaching vehicle, the millimeter-wave radar outputs a corresponding approaching vehicle detection signal to the intelligent control module. Upon receiving the approaching vehicle detection signal, the intelligent control module determines, through a second determination rule, that the approaching vehicle is located within the warning area. In this case, the intelligent control module sends a working signal to the external warning lights and sirens via the sound and light alarm linkage interface, controlling the external warning lights and sirens to start working.
[0019] Preferably, the communication module is a wireless Bluetooth communication module of model E104-BT52.
[0020] Preferably, in the laser matrix projection assembly, the laser lamp control unit includes a three-channel LED driver control chip of model TM1903, which is used to perform RGB three-color control on the laser light source and supports 256 levels of grayscale PWM dimming.
[0021] Preferably, the laser lamp driving unit includes a constant voltage and constant current driving circuit, which includes a voltage regulating sub-circuit and a current limiting sub-circuit. The voltage regulating sub-circuit is equipped with a synchronous step-down DC-DC converter (model SY8105ADC) to convert the output voltage of the vehicle power supply into a constant driving voltage for driving the laser light source. The current limiting sub-circuit is equipped with a linear step-down LED constant current driver (model OC7141) to adjust the output current of the vehicle power supply and convert it into a constant driving current for driving the laser light source.
[0022] The beneficial effects of this invention are as follows:
[0023] Overall, the intelligent safety warning system provided by this patent integrates a vehicle information collection module, a communication module, a projection angle detection module, an intelligent control module, and a laser matrix projection component, based on the vehicle power supply, to achieve rapid deployment and remote control of the safety warning system on the vehicle side.
[0024] Specifically, the communication module works with the mobile terminal to send configuration parameters such as the horizontal projection distance s, the preset height h, and the number of lanes n to the intelligent control module. The intelligent control module quickly determines the length s and width w of the warning area according to the preset configuration rules, so that the warning range can be flexibly adjusted according to the number of lanes and the working distance, avoiding the "discontinuous warning and unclear boundary" caused by the time-consuming deployment of traditional cones / signs and the fixed warning shape.
[0025] In addition, the projection angle detection module outputs the actual projection angle ∠β, and the intelligent control module compares it with the theoretical projection angle ∠α determined by s and h to make a threshold judgment and complete the calibration, so as to ensure that the laser matrix stably forms a clear and visible warning boundary / pattern on the ground, and still has a high recognition distance in low visibility conditions such as curves, slopes, night, and rain and fog.
[0026] Based on this, the vehicle information acquisition module acquires the distance and speed of oncoming vehicles in real time and outputs oncoming vehicle detection signals. The intelligent control module, combined with the second judgment rule, effectively identifies the intruding target and triggers external warning lights and sirens through the sound and light alarm linkage interface to achieve hierarchical linkage and active enhancement of warnings, thereby providing more time for following vehicles to detect, brake and change lanes, and reducing the risk of secondary accidents.
[0027] In addition, the laser lamp driving unit adopts a constant voltage and constant current driving circuit, which, together with the optical shaping components, realizes arrayed high-brightness projection, improves output stability and adaptability, and extends the life of the laser light source. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 This is a flowchart illustrating the overall operation of the intelligent safety warning system in this invention.
[0030] Figure 2 This is a flowchart illustrating the overall operation of the laser matrix projection component in this invention.
[0031] Figure 3This is a schematic diagram of the projection method of the laser matrix projection component in this invention;
[0032] Figure 4 This is a schematic diagram illustrating the data collection method of the vehicle information collection module in this invention. Detailed Implementation
[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0034] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0035] In the intelligent security alert system provided in this application, such as Figure 1-2 As shown, it includes: a vehicle information acquisition module 1, a communication module 2, a projection angle detection module 3, an intelligent control module 4, and a laser matrix projection component 5. The laser matrix projection component 5 includes a laser lamp control unit 501, a laser lamp drive unit 502, a laser light source 503, and an optical shaping component 504. Specifically:
[0036] The intelligent safety warning system is installed as a vehicle-mounted device at the rear or top of law enforcement / maintenance vehicles, for example, by fixing it with a vehicle-mounted bracket. Its power source is either direct power supply from the vehicle or power supply interface, so as to ensure that the equipment can be put into operation quickly after it arrives on site, reducing the time and exposure risk of personnel setting up cones and signs in traffic areas.
[0037] After the intelligent safety warning system is deployed alongside the vehicle, staff output configuration parameters to the intelligent control module 4 via mobile terminal 6 and communication module 2. These parameters include the horizontal projection distance *s* of the laser light source 503, the preset height *h* of the laser light source 503, and the number of lanes *n*. Communication module 2 uses an E104-BT52 wireless Bluetooth communication module.
[0038] Based on this, the intelligent control module 4 determines the width w of the warning area according to the number of lanes n, where w = 3.75n, and the length of the warning area is the horizontal projection distance s of the laser light source 503, using its internal preset configuration rules. It also uses the configuration rules to determine the theoretical projection angle ∠α of the laser light source 503 based on the horizontal projection distance s and the preset height h of the laser light source 503 in the configuration parameters. The specific structure is as follows: Figure 3-4 As shown, based on the derivation formula of trigonometric functions, since tanα=s / h, then ∠α=arctan(α). In this embodiment, the values of s and h are known, so the specific value of ∠α can be determined.
[0039] At this point, the intelligent control module 4 obtains the theoretical values necessary for the normal operation of the intelligent safety warning system, such as the theoretical projection angle ∠α of the laser source 503. Based on this, the intelligent control module 4 determines the warning area on the ground based on the configuration parameters and calibrates the actual projection angle ∠β of the laser matrix projection component 5 based on the angle feedback signal. That is, the intelligent control module 4 uses the projection angle detection module 3 to determine whether the actual projection angle ∠β of the laser source 503 meets the requirements. Figure 1 As shown, specifically:
[0040] The projection angle detection module 3 is used to obtain the attitude angle of the laser matrix projection component 5 and output the angle feedback signal to the intelligent control module 4. The projection angle detection module 3 includes a digital angle sensor, which is connected to the intelligent control module 4 through a TTL UART serial port to output the actual projection angle ∠β of the laser light source 503 as the angle feedback signal.
[0041] The intelligent control module 4 also has a preset first judgment rule, which includes an angle error threshold. When the theoretical projection angle ∠α of the laser source 503 is equal to the actual projection angle ∠β, or when the difference between the theoretical projection angle ∠α and the actual projection angle ∠β does not exceed the angle error threshold, the first judgment rule determines that the actual projection angle ∠β calibration is complete. At this time, the intelligent control module 4 issues a warning control signal, controls the laser matrix projection component 5 to output laser light and form a warning pattern within the warning area; when the difference between the theoretical projection angle ∠α and the actual projection angle ∠β of the laser source 503 exceeds the angle error threshold... The first judgment rule determines that the actual projection angle ∠β needs to be calibrated. At this time, the intelligent control module 4 sends a calibration signal to the mobile terminal 6 through the communication module 2. After receiving the calibration signal, the mobile terminal 6 displays the calibration information. During this process, the threshold judgment of the actual projection angle ∠β by the intelligent control module 4 is always carried out throughout the entire operation of the intelligent safety warning system. When the staff learns from the display of the mobile terminal 6 that the actual projection angle ∠β of the laser source 503 needs to be calibrated and adjusted, they can manually adjust the actual projection angle ∠β of the laser source 503 in the laser matrix projection component 5 until the calibration is completed.
[0042] At this time, the intelligent control module 4 issues an alarm control signal to control the laser matrix projection component 5 to form an alarm pattern within the alarm area.
[0043] Specifically, such as Figure 2 As shown, in the laser matrix projection component 5, the laser light control unit 501 is electrically connected to the intelligent control module 4 to receive warning control signals and generate cascaded control data. The laser light control unit 501 includes a three-channel LED driver control chip of model TM1903. The three-channel LED driver control chip is used to perform RGB three-color control on the laser light source 503 and supports 256 levels of grayscale PWM dimming, so that the color and brightness of the warning pattern can be adjusted as needed to meet different requirements in different scenarios.
[0044] The laser light driver unit 502 is electrically connected to the laser light control unit 501 and is used to drive the laser light source 503 with constant voltage and constant current and to dim it with PWM according to the cascaded control data. The laser light driver unit 502 includes a constant voltage and constant current drive circuit, which includes a voltage regulation sub-circuit and a current limiting sub-circuit. The voltage regulation sub-circuit is equipped with a synchronous step-down DC-DC converter of model SY8105ADC, which is used to convert the output voltage of the vehicle power supply into a constant drive voltage for driving the laser light source 503. The current limiting sub-circuit is equipped with a linear step-down LED constant current driver of model OC7141, which is used to adjust the output current of the vehicle power supply and convert it into a constant drive current for driving the laser light source 503.
[0045] The optical forming component 504 is disposed on the light output path of the laser source 503 to perform array forming of the laser and form the warning pattern on the ground. The optical forming component 504 mainly includes a grating lens, which is a diffractive optical element. The warning pattern is preset in the grating lens using the existing process technology of micro-nano lithography. The optical forming component 504 also includes a bracket for mounting the grating lens.
[0046] In addition, the intelligent safety warning system also detects and warns oncoming vehicles during operation. Specifically, the intelligent safety warning system also includes a vehicle information collection module 1.
[0047] The vehicle information acquisition module 1 is used to acquire information about approaching vehicles and output corresponding approaching vehicle detection signals to the intelligent control module 4. The vehicle information acquisition module 1 includes a millimeter-wave radar, which is connected to the intelligent control module 4 through a serial communication interface. After the millimeter-wave radar acquires the detection data of the distance and speed of the approaching vehicle, it outputs the corresponding approaching vehicle detection signal to the intelligent control module 4. After receiving the approaching vehicle detection signal, the intelligent control module 4 determines that the approaching vehicle is within the warning area according to the second judgment rule. At this time, the intelligent control module 4 sends a working signal to the external warning lights and sirens 7 through the sound and light alarm linkage interface to control the external warning lights and sirens 7 to start working.
[0048] It should be noted in this application that the functions of each module described herein, as well as the TTL UART serial port, three-channel LED driver control chip, synchronous step-down DC-DC converter, and linear step-down LED constant current driver, are all substitutions of existing technologies. Therefore, this application only describes their functions. In addition, this application describes and limits the specific functions of the configuration rules, the first determination rule, and the second determination rule in the intelligent control module 4, indicating that any control rule that can achieve the corresponding function in the prior art is acceptable. Since the core improvement point of this application is not the control rules themselves, they are not described in detail here. Those skilled in the art can make appropriate selections from the prior art based on the function descriptions. Furthermore, the units of w, s, and h as explained in this application are all meters.
[0049] In general, the intelligent safety warning system provided in this application integrates a vehicle information acquisition module 1, a communication module 2, a projection angle detection module 3, an intelligent control module 4, and a laser matrix projection component 5, based on being powered by an on-board power supply, to achieve rapid deployment and remote control of the safety warning system on the vehicle side.
[0050] The communication module 2 works in conjunction with the mobile terminal 6 to send configuration parameters such as horizontal projection distance s, preset height h, and number of lanes n to the intelligent control module 4. The intelligent control module 4 quickly determines the length s and width w of the warning area according to the preset configuration rules, so that the warning range can be flexibly adjusted according to the number of lanes and the working distance, avoiding the "discontinuous warning and unclear boundary" caused by the time-consuming deployment of traditional cones / signs and the fixed warning form.
[0051] In addition, the projection angle detection module 3 outputs the actual projection angle ∠β, and the intelligent control module 4 performs threshold judgment and calibration with the theoretical projection angle ∠α determined by s and h to ensure that the laser matrix stably forms a clear and visible warning boundary / pattern on the ground, and still has a high recognition distance in low visibility conditions such as curves, slopes, nights, and rain and fog.
[0052] Based on this, the vehicle information acquisition module 1 acquires the distance and speed of oncoming vehicles in real time and outputs oncoming vehicle detection signals. The intelligent control module 4 combines the second judgment rule to effectively identify the intruding target and triggers the external warning lights and sirens 7 through the sound and light alarm linkage interface to achieve hierarchical linkage and active enhancement of warnings, thereby providing more time for vehicles behind to detect, brake and change lanes, and reducing the risk of secondary accidents.
[0053] In addition, the laser lamp driving unit 502 adopts a constant voltage and constant current driving circuit, which, together with the optical shaping component 504, realizes arrayed high-brightness projection, improves output stability and adaptability, and extends the life of the laser light source.
[0054] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An intelligent safety warning system, characterized in that, include: The vehicle information acquisition module is used to acquire information about approaching vehicles and output corresponding approaching vehicle detection signals to the intelligent control module. The communication module is used to establish a wireless communication connection with the mobile terminal and to output configuration parameters to the intelligent control module through the mobile terminal and the communication module. The projection angle detection module is used to obtain the attitude angle of the laser matrix projection component and output an angle feedback signal to the intelligent control module. The intelligent control module determines the warning area on the ground based on configuration parameters and calibrates the actual projection angle of the laser matrix projection component based on the angle feedback signal. Once calibration is complete, the intelligent control module issues a warning control signal to control the laser matrix projection component to form a warning pattern within the warning area. When it receives a vehicle detection signal from the vehicle information acquisition module, the intelligent control module sends a working signal to the external warning lights and sirens via the sound and light alarm linkage interface, controlling the external warning lights and sirens to start working. The laser matrix projection assembly includes a laser light control unit, a laser light driving unit, a laser light source, and an optical shaping assembly. The laser light control unit is electrically connected to the intelligent control module to receive warning control signals and generate cascaded control data. The laser light driving unit is electrically connected to the laser light control unit to drive the laser light source with constant voltage and current and perform PWM dimming according to the cascaded control data. The optical shaping assembly is disposed on the light emission path of the laser light source to array and shape the laser light, forming the warning pattern on the ground. The intelligent safety warning system is powered by the vehicle's power supply for normal operation.
2. The intelligent safety warning system according to claim 1, characterized in that: The configuration parameters include the horizontal projection distance s of the laser light source, the preset height h of the laser light source, and the number of lanes n.
3. The intelligent safety warning system according to claim 2, characterized in that: The projection angle detection module includes a digital angle sensor, which is connected to the intelligent control module via a TTL UART serial port to output the actual projection angle ∠β of the laser light source as the angle feedback signal.
4. The intelligent safety warning system according to claim 3, characterized in that: The intelligent control module has an internal preset configuration rule, which determines the width w of the warning area based on the number of lanes n, and the length of the warning area is the horizontal projection distance s of the laser light source. Furthermore, the configuration rules determine the theoretical projection angle ∠α of the laser source based on the horizontal projection distance s and the preset height h of the laser source in the configuration parameters. The intelligent control module also has a preset first judgment rule, which includes an angle error threshold. When the theoretical projection angle ∠α of the laser source is equal to the actual projection angle ∠β, or when the difference between the theoretical projection angle ∠α and the actual projection angle ∠β does not exceed the angle error threshold, the first judgment rule determines that the actual projection angle ∠β has been calibrated. At this time, the intelligent control module issues a warning control signal, controls the laser matrix projection component to output laser light and form a warning pattern in the warning area. When the difference between the theoretical projection angle ∠α and the actual projection angle ∠β of the laser source exceeds the angle error threshold, the first judgment rule determines that the actual projection angle ∠β needs to be calibrated. At this time, the intelligent control module sends a calibration signal to the mobile terminal through the communication module. After receiving the calibration signal, the mobile terminal displays the calibration information.
5. The intelligent safety warning system according to claim 4, characterized in that: The vehicle information acquisition module includes a millimeter-wave radar, which is connected to the intelligent control module via a serial communication interface. After acquiring detection data of the distance and speed of the approaching vehicle, the millimeter-wave radar outputs a corresponding approaching vehicle detection signal to the intelligent control module. Upon receiving the approaching vehicle detection signal, the intelligent control module determines, through a second determination rule, that the approaching vehicle is located within the warning area. In this case, the intelligent control module sends a working signal to the external warning lights and sirens via the sound and light alarm linkage interface, controlling the external warning lights and sirens to start working.
6. The intelligent safety warning system according to claim 5, characterized in that: The communication module is a wireless Bluetooth communication module with model number E104-BT52.
7. The intelligent safety warning system according to claim 6, characterized in that: In the laser matrix projection assembly, the laser lamp control unit includes a three-channel LED driver control chip of model TM1903. The three-channel LED driver control chip is used to perform RGB three-color control on the laser light source and supports 256 levels of grayscale PWM dimming.
8. The intelligent safety warning system according to claim 7, characterized in that: The laser lamp driving unit includes a constant voltage and constant current driving circuit, which includes a voltage regulating sub-circuit and a current limiting sub-circuit. The voltage regulating sub-circuit is equipped with a synchronous step-down DC-DC converter (model SY8105ADC) to convert the output voltage of the vehicle power supply into a constant driving voltage for driving the laser light source. The current limiting sub-circuit is equipped with a linear step-down LED constant current driver (model OC7141) to adjust the output current of the vehicle power supply and convert it into a constant driving current for driving the laser light source.