Based on vehicle dimension automatic measurement system and the measuring method thereof of light curtainTechnical field
The present invention relates to a kind of vehicle dimension detection system, especially a kind of vehicle dimension automatic measurement system based on light curtain and measuring method thereof.
Background technology
The development of auto industry, greatly facilitates socioeconomic development, but also therefore brings a lot of traffic problems.In the annual frequent traffic hazard occurred, the ratio causing following traffic hazard because of vehicle overall dimensions constantly rises: part is used for the vehicle driver of visitor/shipping purposes to obtain larger economic interests, by repacking vehicle dimension to increase vehicle volume, reach and increase the object that the disposable transport of vehicle reduces transportation cost, this behave seriously violates the safety standard that vehicle uses, the goods reprinted due to the vehicle of super large overall dimensions is also larger, often cause danger when the bridge by having less holding capacity or width of roadway do not allow two ultra-wide vehicles to walk abreast, traffic hazard every year because of overload of vehicle generation is of common occurrence.In order to ensure the security of vehicle, vehicle all must carry out annual test every year, but carry out in manual measurement mode often when detecting vehicle dimension at present, its Problems existing is: 1, testing result error is comparatively large, cannot ensure the accuracy measured; 2, detection time is longer, inefficiency, and takies more human and material resources; 3, automaticity is low, can not meet the growth requirement that motor vehicle management department manages motorized vehicles implementation informationization.For the problems referred to above, current main solution is that the method adopting camera review to capture obtains vehicle overall size.
Number of patent application is give in the document of 03114546.9 " the vehicle overall dimensions detection system of image based process ", it obtains front elevation by image acquisition unit, side view, vertical view three width contour of the vehicle image, enter storer, digital processing unit reads in three width contour of the vehicle pictorial data successively from storer, through analyzing motor vehicles appearance image, height and the width of vehicle is obtained from the front elevation of vehicle, height and the length of vehicle is obtained from the side view of vehicle, width and the length of vehicle is obtained from the vertical view of vehicle, the three groups of data detected are weighted and on average draw that there are reliable and accurate vehicle overall dimensions.Although this technical scheme can obtain the physical dimension of motor vehicles, its Problems existing is: 1, limit by gamma camera optimal viewing angle and coverage, and the motor vehicle physical dimension of picked-up also exists error; 2, lack obvious object of reference picture in this technical scheme to carry out parameters revision, make testing result there is error.
Patent documentation ZL200920079045.7 proposes " obtains the Automatic Measuring Apparatus of vehicle image measurement vehicle contour dimension in motion, its implementation is: by falling " L " side of shape column steelframe and top install two or more sets video cameras and take passing vehicle, thus obtain side view and the vertical view of vehicle, and splice by continuous image shooting in imaginary Virtual Space the length finally obtaining vehicle again, and, its Ce Kuan mechanism is high with survey, length measuring mechanism according in captured picture to the circumstance of occlusion of ground mark and facade mark, the both sides be not blocked from picture or up and down between distance values obtain width or the height of vehicle reality.Although this technical scheme can both realize the measurement to motor vehicles shell sizes, but, its Problems existing is: 1, sectional drawing overlooked by captured vehicle, side-looking sectional drawing is due to wide with the survey of its correspondence, survey high, survey long denotation thing not in same plane, its measurement result often has error, such as, when vehicle is not vertical row and then angle presentation deviation is advanced, or the position that is taken of vehicle is not when reaching the object distance range forming sharp image, the spacing on the both sides that Ce Kuan mechanism is not blocked from high vertical view draws vehicle width, it not often the width of vehicle, in like manner show that the height of measuring vehicle in this way also has error, 2, when by continuous shooting picture, also spelling is gone back map interlinking sheet thus obtains the length of vehicle in a certain region, because dynamic continuous shooting often causes face image to there is distortion or distortion, what then cannot realize between image is seamless spliced, thus can not the accurate the length dimension calculating vehicle.
In sum, the method of video capture image and then measuring vehicle physical dimension is adopted to there is following problem: 1, when adopting survey mark object space method to measure, due to surface mark thing or facade mark with the sectional drawing of captured image not in a plane, cause image appearance scale error; 2, by the restriction of video camera optimal viewing angle and coverage, often there is error in captured image; 3, when adopting ground reference to measure, owing to lacking the parameters revision of clear and definite reference image as measuring vehicle physical dimension, making image procossing, analytic process complicated, thus adding measurement difficulty.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, provide a kind of reasonable in design, measuring accuracy is high and measure easily based on vehicle dimension automatic measurement system and the measuring method thereof of light curtain.
The present invention solves its technical matters and takes following technical scheme to realize:
A kind of vehicle dimension automatic measurement system based on light curtain, connected and composed by measurement main frame, signal pickup assembly and picking sensor array, described picking sensor array is by surveying high picking sensor, surveying wide picking sensor, surveying the spatial structure that long picking sensor forms, the output terminal of long picking sensor surveyed high picking sensor, survey wide picking sensor, survey is connected with signal pickup assembly, measures after main frame receives the detection signal that picking sensor array transmits and calculates height of car to be measured, vehicle width, length.
And the high picking sensor of described survey comprises an illuminator L1 and the light receiving device S1 corresponding with it, the high picking sensor of this survey is mounted opposite perpendicular in the Z axis plane on ground; The long picking sensor of described survey comprises two illuminators L2, L3 and corresponding with it two light receiving devices S2, S3, and two illuminators L2, L3 and two light receiving devices S2, S3 are mounted opposite respectively in the X-axis plane being parallel to ground; The wide picking sensor of described survey comprises two illuminators L4, L5 and two light receiving devices S4, S5, and two illuminators L4, L5 and two light receiving devices S4, S5 are mounted opposite respectively between upper and lower two planes formed perpendicular to Z axis and by X-axis, Y-axis.
And, described picking sensor array also comprises a location appearance picking sensor, this location appearance picking sensor comprises the wide picking sensor of survey that two rows are parallel to each other, often the installation site of the wide picking sensor of row's survey is: in the plane be made up of Y-axis, X-axis, draw a center line along X-direction, centrally each one group of picking sensor of each discharge straggly before and after line both sides, parallel along X-direction between two groups of picking sensors; Along Y direction, with center line be boundary each other from a distance, form the unglazed curtain region along X-direction of an elongate in shape.
And, described signal pickup assembly built-in method be plugged in measure in main frame and by serial ports with survey high picking sensor, survey wide picking sensor, survey long picking sensor and location appearance picking sensor is connected.
And, described signal pickup assembly to be connected with measurement main frame by serial ports or network interface by external method and by serial ports with the high picking sensor of survey, survey wide picking sensor, survey long picking sensor and location appearance picking sensor is connected.
And whether described measurement main frame is also connected with a parking stall measure sensor needs measuring car with the work of control signal collector for detecting.
Based on a vehicle dimension method for automatic measurement for light curtain, comprise the following steps:
Step 1: by the parking stall measure sensor of pre-plugged, detects whether need measuring car;
Step 2: if vehicle to be measured detected, triggering picking sensor array is started working by signal picker;
Step 3: when vehicle to be measured enters picking sensor array, by surveying high picking sensor, location appearance picking sensor and surveying the corresponding signal of wide picking sensor collection and send measurement main frame in a collection period, by measurement main frame measuring vehicle height, vehicle pose and vehicle width;
Step 4: when vehicle to be measured remains static and falls into the light curtain region of measuring vehicle length, survey long picking sensor collection signal and send measurement main frame to, carries out measuring vehicle length by measurement main frame.
And the method for measuring vehicle height is in described step 3: when vehicle to be measured enters the high picking sensor scope of survey, the extreme higher position of the optical axis that is blocked along Z-direction;
In described step 3, measuring vehicle pose is obtained by following calculated with mathematical model:
tagθ＝(H2-H1)/LT1
In formula: θ is vehicle pose, centered by H1, line is to the distance of a point, and a point is that a location appearance picking sensor light curtain is along maximal value in Y direction; Centered by H2, line is to the distance of b point, and b point is that another location appearance picking sensor is along maximal value in Y direction; LT1 is the distance of two location appearance picking sensors;
In described step 3, measuring vehicle width W is obtained by following computation model:
W＝cosθ*LT4
Wherein, θ is vehicle pose, and the length value of LT4 equals the distance between a, d, and a, d to be blocked the maximal value of optical axis along the be blocked minimum value of optical axis and light curtain of Y direction light curtain.
And measuring vehicle length LT adopts following calculated with mathematical model to obtain in described step 4:
LT＝S2/cosθ
In formula, ST2=ST-ST1, ST value equals along the distance between X-direction a, b, and a is the minimum value along X-direction light curtain, and b is the maximal value along X-direction light curtain;
ST1=sin θ * W, W is vehicle width.
Advantage of the present invention and good effect are:
The present invention is reasonable in design, by surveying high picking sensor, survey wide picking sensor, survey long picking sensor to treat measuring car and carry out height of car, width, the detection of length, detected by the attitude of location appearance picking sensor to vehicle simultaneously, again according to the attitude of vehicle to the length of vehicle, width carries out the effective compensation at angle of inclination, thus the Measurement accuracy function achieved vehicle dimension, solve camera review to take pictures the error of image appearance size that measuring method do not cause because of shooting sectional drawing and surface mark thing and facade mark in same plane, improve measuring accuracy and stability, no matter from the easy degree of process, antijamming capability and maintainability all increase significantly.
Accompanying drawing explanation
Fig. 1 is system connection diagram of the present invention;
Fig. 2 is the mounting arrangement schematic diagram of four kinds of picking sensors;
Fig. 3 is measuring method processing flow chart of the present invention;
Fig. 4 is the principle schematic of measuring vehicle height;
Fig. 5 is the schematic layout pattern of location appearance picking sensor;
Fig. 6 is the principle schematic of measuring vehicle pose;
Fig. 7 is the principle schematic (pose angle θ is zero) of measuring vehicle width;
Fig. 8 is the principle schematic (pose angle θ is non-vanishing) of measuring vehicle width;
Fig. 9 is the principle schematic (pose angle θ is zero) of measuring vehicle length;
Figure 10 is the principle schematic (pose angle θ is non-vanishing) of measuring vehicle length.
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the present invention is further described:
A kind of vehicle dimension automatic measurement system based on light curtain, as shown in Figure 1, by measurement main frame, signal pickup assembly and picking sensor array connect and compose, this picking sensor array is by surveying high picking sensor, survey wide picking sensor, survey the spatial structure of long picking sensor and location appearance picking sensor formation, survey high picking sensor, survey wide picking sensor, survey long picking sensor to be connected with signal pickup assembly by RS232 serial ports with the output terminal of location appearance picking sensor, signal pickup assembly can be plugged in be measured in main frame, also can be connected with measurement main frame by serial ports or network interface, in measurement main frame, vehicle dimension computing module is installed for calculating height of car to be measured, vehicle width, measurement result is also shown by main frame by length and pose.The height of this picking sensor array real-time measuring vehicle in a signal acquisition periods, pose and width, the length of measuring vehicle when static state.
As shown in Figure 2, the mounting arrangement of picking sensor array is: survey high picking sensor and comprise an illuminator L1 and the light receiving device S1 corresponding with it, and the high picking sensor of this survey is mounted opposite perpendicular in the Z axis plane on ground; Survey long picking sensor and comprise two illuminators L2, L3 and corresponding with it two light receiving devices S2, S3, two illuminators L2, L3 and two light receiving devices S2, S3 are mounted opposite respectively in the X-axis plane being parallel to ground; Survey wide picking sensor and comprise two illuminators L4, L5 and two light receiving devices S4, S5, two illuminators L4, L5 and two light receiving devices S4, S5 are mounted opposite respectively between upper and lower two planes formed perpendicular to Z axis and by X-axis, Y-axis; Location appearance picking sensor comprises the wide picking sensor of survey that two rows are parallel to each other, i.e. four illuminators L4, L5, L6, L7 and four light receiving devices S4, S5, L6, S7 corresponding thereto, often row surveys the installation site of wide picking sensor: in the plane be made up of Y-axis, X-axis, draw a center line along X-direction, centrally each one group of picking sensor of each discharge straggly before and after line both sides, parallel along X-direction between two groups of picking sensors; Along Y direction, with center line be boundary each other from a distance, form the unglazed curtain region along X-direction of an elongate in shape.
Picking sensor principle utilizes each root infrared ray (ultrared quantity and dense degree are determined by spacing between the optical axis quantity set and optical axis) exactly, when measuring vehicle height, width, length, respectively vehicle is cut into dozens of measurement plane, obtain the height of wherein highly the highest level as vehicle, obtain plane width that wherein width the is the widest width as vehicle, obtain plane length that wherein length the is the longest length as vehicle.The fundamental difference that videographic measurment and light curtain are measured is that light curtain measuring method directly measures vehicle to be measured, solve photographing measurement method by lens articulation, optimal viewing angle, the factor such as coverage, camera calibration can affect larger problem.Meanwhile, adopt location appearance picking sensor can obtain vehicle pose accurately, this vehicle pose is a very crucial parameter, obtains vehicle width and Vehicle length accurately by carrying out angle of inclination compensation to vehicle pose.
Based on a vehicle dimension method for automatic measurement for light curtain, as shown in Figure 3, comprise the following steps:
1, by the parking stall measure sensor of pre-plugged, detect whether need measuring car;
If 2 detect vehicle to be measured, triggering picking sensor array is started working by signal picker;
3, when vehicle to be measured enters picking sensor array, by surveying high picking sensor, location appearance picking sensor and surveying the corresponding signal of wide picking sensor collection and send measurement main frame in a collection period, by measurement main frame measuring vehicle height, vehicle pose and vehicle width;
Below the measuring method of height of car, vehicle pose and vehicle width is described respectively:
(1) height of car measuring method: as shown in Figure 4, when vehicle to be measured enters the high picking sensor scope of survey, to produce shading to the high picking sensor of survey (illuminator L1 and light receiving device S1), be exactly the height of vehicle to be measured along the be blocked extreme higher position L1_S1_6 (light curtain L1_S1 is the 6th optical axis from bottom to top) of optical axis of Z-direction.
(2) vehicle pose measuring method, as shown in Figures 5 and 6, when vehicle to be measured passes some row's light curtains of center line both sides, can produce the light curtain passing perpendicularly through vehicle body and block, pick up the car wore the most edge of Liang Paicekuan mechanism two optical axises that are blocked as two points, organize into a line, this line and center line formed a tilt angle theta, this angle of inclination is referred to as vehicle pose, and this vehicle pose θ is obtained by following calculated with mathematical model:
tagθ＝(H2-H1)/LT1
In formula: centered by H1, line is to the distance of a point, a point is for the light curtain that is blocked (the illuminator L4 of location appearance picking sensor and light receiving device S4) is along maximal value in Y direction; Centered by H2, line is to the distance of b point, and b point is for the light curtain that is blocked (the illuminator L6 of location appearance picking sensor and light receiving device S6) is along maximal value in Y direction; LT1 is the distance of the light curtain between illuminator L4 and light receiving device S4 and the light curtain between illuminator L6 and light receiving device S6, in Fig. 6, and θ=θ 1.
(3) vehicle width measuring method: as shown in Figure 7, when vehicle to be measured enters the wide picking sensor scope of survey, shading is produced by the wide picking sensor of survey (surveying illuminator L4 and light receiving device S4, illuminator L5 and the light receiving device S5 of wide sensor), if vehicle pose θ is 0, then can be calculated the width of vehicle by the minimum value L4_S4_6 of the optical axis that is blocked along Y direction (light curtain L4_S4 from centre left the 6th optical axis) and maximal value L5_S5_6 (light curtain L5_S5 from centre to the right the 6th optical axis); If vehicle pose θ is not 0, as shown in Figure 8, then carry out angle of inclination compensation according to vehicle pose θ to vehicle width, thus obtain vehicle width to be measured accurately, the computation model of vehicle width W (in figure LT3) is:
W＝cosθ*LT4
Wherein, θ is vehicle pose (angle of inclination), and the length value of LT4 equals the distance between a, d, and a, d to be blocked the maximal value L4_S4_6 of optical axis, θ=θ 2 along the be blocked minimum value L5_S5_6 of optical axis and light curtain of Y direction light curtain.
4, when vehicle to be measured remains static and fall into the light curtain region of measuring vehicle length, survey long picking sensor collection signal and send measurement main frame to, carrying out measuring vehicle length by measurement main frame.
Vehicle length measuring method: as shown in Figure 9, when vehicle enters the long picking sensor scope of survey, shading is produced by the long picking sensor of survey (the illuminator L2 of the long picking sensor in side and light receiving device S2, illuminator L3 and light receiving device S3), if vehicle pose θ is 0, then can be calculated the length of vehicle by the minimum value L2_S2_7 of the optical axis that is blocked along X-direction (light curtain L2_S2 from centre left the 7th optical axis) and maximal value L3_S3_8 (light curtain L3_S3 from centre to the right the 8th optical axis); If vehicle pose θ is not 0, as shown in Figure 10, then according to vehicle pose θ, angle of inclination compensation is carried out to Vehicle length, thus obtain vehicle width accurately.The computation model of Vehicle length LT is:
LT＝ST2/cosθ
In formula, ST2=ST-ST1, ST value equals along the distance between X-direction a, b, a is the minimum value along X-direction light curtain (illuminator L4 and light receiving device S4) or (illuminator L5 and light receiving device S5), and b is the maximal value along X-direction light curtain (illuminator L6 and light receiving device S6) or (illuminator L7 and light receiving device S7);
ST1=sin θ * W, W is vehicle width.
By above-mentioned steps, can realize realizing accurate measurement function to height of car, vehicle width and length.
It is emphasized that; embodiment of the present invention is illustrative; instead of it is determinate; therefore the present invention is not limited to the embodiment described in embodiment; every other embodiments drawn by those skilled in the art's technical scheme according to the present invention, belong to the scope of protection of the invention equally.