CN104729459A - Driving ranging and collision warning unit based on ARM-Linux system - Google Patents

Abstract

The invention discloses a driving distance measurement anti-collision early warning device based on ARM-Linux system, wherein an image acquisition module, a display and Linux human-computer interaction module, and an alarm module are respectively connected with a control module; The laser spot is formed on the surface of the object; the image acquisition module is used to collect the image information of the obstacle; the control module is used to process the image information of the obstacle to obtain the distance between the image acquisition module and the obstacle; the display and Linux human-computer interaction module is used to The distance information between the image acquisition module and the obstacle surface is displayed, and the alarm module is controlled by the control module to send out an alarm signal. The distance measuring anti-collision warning device for driving based on the ARM-Linux system of the present invention has the characteristics of good anti-interference performance, high measurement accuracy and good real-time performance, and is suitable for popularization in the driving field because of its simple structure.

Description

Driving distance measurement and anti-collision warning device based on ARM-Linux system

technical field

The invention belongs to the field of anti-collision devices, in particular to an ARM-Linux system-based anti-collision early warning device for driving range measurement.

Background technique

Cranes (also known as bridge cranes or overhead cranes) are important mechanical equipment for vertically lifting or horizontally moving heavy objects on industrial sites. With the continuous development of economic construction, the application of cranes has become more and more widespread. It is increasingly common for many large industrial sites to operate multiple cranes on the same floor. Due to the heavy work tasks of operators, the attention is highly concentrated on the heavy objects to be lifted The lifting and horizontal position status of the vehicle often ignores the safety distance between adjacent vehicles, resulting in frequent collision accidents, especially the collision between the same straddle vehicle brings immeasurable consequences and losses to personal safety and equipment safety. In order to solve the problem of collisions between vehicles due to the short distance, anti-collision devices need to be installed on vehicles. The existing anti-collision methods mainly include mechanical, infrared, laser, ultrasonic and radar, etc., but these methods are based on their The anti-collision principle and its characteristics have limitations in driving applications. Among them, although the mechanical anti-collision device has a simple structure and low cost, the reliability of the work is affected by the vibration of the protruding angle steel during installation and debugging; the infrared method has high accuracy, but the detection distance is too short and does not meet the real-time requirements; the laser method The requirements for the smoothness of the surface of the optical mirror are relatively high; ultrasonic and radar are greatly affected by the weather and have poor reliability.

Contents of the invention

Aiming at the problems in the prior art, the present invention provides a distance measuring and anti-collision warning device based on the ARM-Linux system, which has the characteristics of good anti-interference performance, high measurement accuracy and good real-time performance. Due to its simple structure, it is suitable for Promoted in the field of driving.

The technical scheme that the present invention adopts to solve its technical problem is: a kind of driving distance measurement anti-collision warning device based on ARM-Linux system, including laser emission module, image acquisition module, display and Linux human-computer interaction module, control module, alarm Module, image acquisition module, display and Linux human-computer interaction module, and alarm module are respectively connected with the control module; the laser emitting module emits a laser beam and irradiates the surface of the obstacle to form a laser spot; the image acquisition module is used to collect image information of the obstacle; the control module It is used to process the obstacle image information to obtain the distance between the image acquisition module and the obstacle; the display and Linux human-computer interaction module is used to display the distance information between the image acquisition module and the obstacle surface, and the alarm module is controlled by The module control sends out an alarm signal.

According to the above technical solution, the image acquisition module is a camera, the laser emitting module is located directly above or directly below the camera, and the laser beam emitted by the laser emitting module is parallel to the central optical axis of the camera.

According to the above-mentioned technical scheme, the control module uses the ARM11 chip S3C6410 chip as the core processor. The main frequency is 533MHz, and the maximum can reach 667MHz, which can easily handle images and Linux interface operations.

According to the above technical solution, the alarm signal includes a voice signal for voice announcement of the distance between the image acquisition module and the obstacle and a danger alarm signal when the obstacle reaches a preset threshold distance.

According to the above technical solution, the control module processes the obstacle image information to obtain the distance between the image acquisition module and the obstacle surface, which specifically includes calculating the number of pixels pfc in the image formed by the laser spot on the focal plane of the camera , calculate the value of radian rpc and radian compensation ro of each pixel, rpc is because the focal plane (imaging surface) of the camera is curved, so that each pixel is distributed in a certain radian when it is on the focal plane. Calculate θ according to the formula θ=pfc*rpc+ro, θ is the angle between the line connecting the laser spot and the center point of the camera optical imaging system and the optical axis of the camera optical imaging system, according to the set laser emission module and image acquisition module The distance h between, through D=h/tanθ, the distance D between the laser emitting module and the obstacle surface is obtained.

According to the above technical solution, the calculation of the number of pixels in the image formed by the laser spot on the focal plane of the camera specifically includes performing grayscale, smoothing filtering and edge feature extraction processing on the image formed by the laser spot on the focal plane of the camera, Then according to the circle fitting method, use the least square principle to approach the contour of the image formed by the laser spot on the focal plane of the camera with a circle, calculate the radius and coordinates of each pixel in the image formed by the laser spot on the focal plane of the camera, and convert the laser The coordinates of each pixel in the image formed by the light spot on the focal plane of the camera are compared with the coordinates of the center pixel of the focal plane of the camera.

The beneficial effects produced by the present invention are: firstly, the distance measuring and anti-collision warning device of the present invention emits a laser beam from the laser emitting module to irradiate the surface of the obstacle to form a laser spot, and the image acquisition device collects and obtains the image information of the obstacle, and the image of the obstacle contains the laser beam Spot information, after processing the information, calculate the current distance between the image acquisition module and the obstacle, and display it on the display and the Linux human-computer interaction module, the operator can see the distance display intuitively, and the control module according to After the current distance is compared with the safety threshold distance, it sends out a voice signal for broadcasting the distance and a danger alarm signal when it is in a dangerous distance, reminding the driver to pay attention to the driving distance, which is helpful for him to make a judgment and take effective measures.

The anti-collision and early warning device for driving range measurement provided by the present invention uses an image acquisition module and a laser beam to assist the anti-collision device to have the characteristics of good anti-interference performance, high measurement accuracy, and good real-time performance. Due to its simple structure, it is suitable for Promoted in the field of driving.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Fig. 1 is a schematic structural view of a driving distance measuring anti-collision warning device according to an embodiment of the present invention;

Fig. 2 is a schematic diagram of the measuring principle of the distance measuring and anti-collision warning device according to the embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

In the embodiment of the present invention, provide a kind of driving distance measurement anti-collision warning device based on ARM-Linux system, as shown in Figure 1, comprise laser emission module, image acquisition module, display and Linux human-computer interaction module, control module, alarm Module, image acquisition module, display and Linux human-computer interaction module, and alarm module are respectively connected with the control module; the laser emitting module emits a laser beam and irradiates the surface of the obstacle to form a laser spot; the image acquisition module is used to collect image information of the obstacle; the control module It is used to process the obstacle image information to obtain the distance between the image acquisition module and the obstacle; the display and Linux human-computer interaction module is used to display the distance information between the image acquisition module and the obstacle surface, and the alarm module is controlled by The module control sends out an alarm signal. In addition to displaying the current distance information, the display and Linux human-computer interaction module also has the function of acquiring collected images to assist driving. The operator can intuitively see the distance display from the display and the Linux human-computer interaction module, and at the same time, the control module will send out a voice signal to announce the distance or a danger alarm signal when it is at a dangerous distance from an obstacle after comparing the current distance with the safety threshold distance. Remind drivers to pay attention to driving distance.

Wherein, the image acquisition module is a camera, the laser emitting module is located directly above or directly below the camera, and the laser beam emitted by the laser emitting module is parallel to the central optical axis of the camera.

Further, the control module uses ARM11 chip S3C6410 chip as the core processor. The main frequency of the ARM11 chip S3C6410 chip is 533MHz, up to 667MHz, which can easily handle images and Linux interface operations.

Further, the alarm signal includes a voice signal for voice announcement of the distance between the image acquisition module and the obstacle and a danger alarm signal when the obstacle reaches a preset threshold distance. Remind the driver to pay attention to the driving distance, which will help them make judgments and take effective measures.

Wherein, the control module processes the obstacle image information to obtain the distance between the image acquisition module and the obstacle surface, which specifically includes calculating the number of pixels pfc in the image formed by the laser spot on the focal plane of the camera, and calculating each The radian rpc of each pixel and the value of radian compensation ro, rpc is because the focal plane (imaging surface) of the camera is a curved surface, so that each pixel is distributed in a certain arc when it is on the focal plane. Calculate θ according to the formula θ=pfc*rpc+ro, θ is the angle between the line connecting the laser spot and the center point of the camera optical imaging system and the optical axis of the camera optical imaging system, according to the set laser emission module and image acquisition module The distance h between, through D=h/tanθ, the distance D between the laser emitting module and the obstacle surface is obtained.

Further, the calculation of the number of pixels in the image formed by the laser spot on the focal plane of the camera specifically includes performing grayscale, smoothing filtering and edge feature extraction processing on the image formed by the laser spot on the focal plane of the camera, and then according to The circle fitting method uses the principle of least squares to approximate the contour of the image formed by the laser spot on the focal plane of the camera with a circle, and calculates the radius and coordinates of each pixel in the image formed by the laser spot on the focal plane of the camera. The coordinates of each pixel in the image formed on the focal plane of the camera are compared with the coordinates of the central pixel of the focal plane of the camera.

Wherein, the value of radian rpc and radian compensation ro of each pixel is calculated, specifically including, the distance h between the laser emitting module and the image acquisition module is fixed, and the distance D between the laser emitting module and the obstacle surface is set to 2 Known value, calculate the included angle θ, and in the case of these two known values D, respectively estimate the coordinates of the pixels in the image formed by the laser spot on the focal plane of the camera, and obtain the laser spot on the focal plane of the camera The number of pixels pfc of the image formed above is respectively substituted into the formula θ=pfc*rpc+ro to obtain 2 equations, and the values of rpc and ro are obtained according to these 2 equations.

In the embodiment of the present invention, as in the experimental system shown in Figure 2, by actually positioning two known distance values D as 31cm and 47cm, image acquisition is carried out at this distance respectively, and the corresponding pfcs obtained after processing are 57 and 30 respectively, And the distance between the laser emitting module and the camera is fixed as h=6.0cm, then a set of equations can be obtained by substituting the ranging formula:

$\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; 31</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 6.0</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 57</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; rpc</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; ro</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; 47</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 6.0</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 30</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; rpc</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; ro</span>}<span\; class="notranslate">\; )</span>\end{array}\right.$

rpc=0.0023986432 and ro=0.055279314 can be calculated according to the equation system. At this time, when the distance D between the laser emitting module and the obstacle surface is any value, only need to process the number of pixels pfc of the laser spot in the image collected at the current distance D on the focal plane of the camera to calculate θ, Further, the current distance value D is calculated according to the formula D=h/tanθ.

The distance measuring method of the device of the present invention is simple, low in complexity, relatively simple in image processing process, high in real-time performance, and can also meet precision requirements, and has wide application prospects.

It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should belong to the protection scope of the appended claims of the present invention.

Claims (6)

1. A distance measuring and anti-collision early warning device based on ARM-Linux system, is characterized in that, comprises laser emitting module, image acquisition module, display and Linux human-computer interaction module, control module, alarm module, image acquisition module, display And the Linux human-computer interaction module and the alarm module are respectively connected with the control module; the laser emitting module emits a laser beam and irradiates the surface of the obstacle to form a laser spot; the image acquisition module is used to collect image information of obstacles; the control module is used to collect image information of obstacles Process to obtain the distance between the image acquisition module and the obstacle; the display and Linux human-computer interaction module is used to display the distance information between the image acquisition module and the obstacle surface, and the alarm module is controlled by the control module to send an alarm signal. 2. the distance measuring and anti-collision warning device based on ARM-Linux system according to claim 1, characterized in that, the image acquisition module is a camera, and the laser emitting module is positioned directly above or directly below the camera, and the laser emitting module sends The laser beam is parallel to the central optical axis of the camera. 3. according to claim 1 or 2 described based on ARM-Linux system driving distance measuring anti-collision early warning device, it is characterized in that, control module uses ARM11 chip S3C6410 chip as core processor. 4. according to claim 1 and 2 described based on the driving range measurement anti-collision warning device of ARM-Linux system, it is characterized in that, warning signal comprises the speech signal and the obstacle of the distance between voice broadcast image acquisition module and obstacle Hazard alarm signal when preset threshold distance is reached. 5. the distance measuring and anti-collision warning device for driving based on ARM-Linux system according to claim 2, characterized in that, said control module processes the obstacle image information to obtain the distance between the image acquisition module and the obstacle surface The distance, specifically includes, calculating the number of pixels pfc in the image formed by the laser spot on the focal plane of the camera, calculating the value of the radian rpc and radian compensation ro of each pixel, and calculating θ according to the formula θ=pfc*rpc+ro, θ is the angle between the line connecting the laser spot and the center of the camera optical imaging system and the optical axis of the camera optical imaging system. According to the set distance h between the laser emitting module and the image acquisition module, through D=h/tanθ, Get the distance D between the laser emitting module and the obstacle surface. 6. the driving distance measurement and anti-collision warning device based on ARM-Linux system according to claim 5, is characterized in that, said calculating the pixel point quantity in the formed image of laser spot on the focal plane of camera, specifically comprises for laser The image formed by the light spot on the focal plane of the camera is grayscaled, smoothed and filtered, and edge feature extraction is processed, and then the circle is used to approximate the contour of the image formed by the laser spot on the focal plane of the camera by using the least squares principle according to the circle fitting method. Compare the coordinates of each pixel in the image formed by the laser spot on the focal plane of the camera with the coordinates of the center pixel of the focal plane of the camera.