CN204480047U - A kind of self-adaptation AGV vision guided navigation sight line adjusting gear - Google Patents

Abstract

The utility model provides a kind of self-adaptation AGV vision guided navigation sight line adjusting gear, this device comprises camera, runing rest, steering wheel, bracing frame, AGV car body and wheel, support frame as described above is anchored on AGV car body, steering wheel is fixed on bracing frame, steering wheel is fixedly connected with runing rest, camera is fixed on runing rest, described camera is positioned on AGV Vehicular body front axis, camera, by the drive adjustable sight line gear angle of steering wheel, adjusts wheel steering by the corner controlling wheel.The utility model can adjust the sight angle of camera automatically according to the speed of AGV car body, camera view is open, and navigator fix controls accurately, thus can increase work efficiency.

Description

A kind of self-adaptation AGV vision guided navigation sight line adjusting gear

Technical field

The utility model belongs to technical field of logistic equipment, is specifically related to a kind of self-adaptation AGV vision guided navigation sight line adjusting gear.

Background technology

AGV is a kind of circuit by setting or the map of setting, and under the control of logistic dispatching system or manual command, automatic running or automatically draw body feed tank, completes the unmanned material handling vehicle of material transfer and handling.Visual guidance is owing to containing much information, line trace and Navigation Control can be realized well in complex environment, in addition, also have construction use cost low simultaneously, guiding the setting of lines and safeguard simple grade for outstanding advantages, is one of major domain of AGV fundamental research and application and development.

Existing visual guidance scheme all adopts hard-wired camera to observe AGV guide line, and setting angle is mostly chosen as vertical ground, obtains the video pictures without perspective effect, reaches the object improving vision positioning precision.For high speed AGV, when AGV car body travelling speed is higher, because camera video frame per second is fixed as 25 frames/second or 30 frames/second usually, the displacement of inter picture likely can exceed the field range of video pictures, makes machine vision complete failure; Therefore, for ensureing the validity of machine vision work, real-time adjustment must be carried out according to the travelling speed of AGV car body to camera sight line, expanding or reduce the size in the video pictures visual field; Correspondingly, the installation form of camera also only should not be perpendicular to ground but before being tilted to, adjustable angle.

Chinese patent application publication number CN1438138A, publication date on August 27th, 2003, the name that utility model is created is called " visual guide method of automatic guide vehicle and automatic guide vehicle thereof ", and this application case discloses disposal route and the electric motor car design proposal of a kind of intake surface running path mark line, station address code identifier and running status control identifier.Its weak point is that single camera is installed on AGV vehicle body vertically downward, and camera view limits by body width, can only see the territory, local cell that AGV car body covers.

Chinese patent application publication No. CN102997910A, date of publication on March 27th, 2013, the name that utility model is created is called " a kind of based on road of ground surface target location guidance system and method ", this application case utilizes light shield and corresponding light fixture to eliminate light source to pollute, and vision sensor vertically downward ground proximity is installed.Its weak point is that camera mounting distance is too low, has tunnel vision and causes quantity of information too low, and the stained ability of anti-lines is more limited.

Chinese patent application publication No. CN103529838A, date of publication on January 22nd, 2014, the name that utility model is created is called " the multi-vision visual guiding drive unit of automatic guided vehicle and collaborative scaling method thereof ", and this application case discloses the apparatus and method that a kind of multiple camera detects guiding lines drift angle and displacement bias.Each camera is all positioned at AGV vehicle body, and camera periphery arbitrary source throws light on, and dig-ins ground guiding lines vertically downward.

Chinese patent grant number CN102346483B, authorized announcement date on November 28th, 2012, the name that utility model is created is called " the AGV progress control method based on passive RFID and accessorial visual ", this mandate arranges that on the ad-hoc location such as stop, turning point LED or charactron are with display and control instruction, the CCD camera that AGV vehicle body side is installed observes the pictorial symbolization on road both sides LED or digital screen, provides the image of steering order.

Chinese Patent Application No. CN102608998A, July 25 2012 Shen Qing Publication day, the name that utility model is created is called " the visual guidance AGV system and method for embedded system ", this application case adopts a forward sight camera and a camera vertically downward simultaneously, forward sight camera collection distant view image, vertical camera is used for secondary accurate positioning.Forward sight camera and ground tilt to install at an angle, prediction is about to turn round, stop, locate before deceleration etc.; The routing information that vertical camera collection is being walked, completes stitching tracing task.Wherein the setting height(from bottom) of forward sight camera is relevant by the maximum operational speed of dolly with ground angle, and solstics, the visual field is 1 ~ 1.2 times of maximum operational speed.Its weak point is, forward sight camera is fixed angle with the setting angle of vertical camera, and fails to provide setting height(from bottom), physical relationship between ground angle and dolly maximum operational speed; Dimension between AGV car body maximum operational speed from solstics, visual field distance is different, and chronomere is unclear, is difficult to the concrete size of clear and definite visual field far point distance AGV car body, random large; Critical weak point is also, vertical camera is close to ground, only has the less visual field, only can keep a close watch on the lines local of a very little part, large losses environmental information, is difficult to adapt to various on-the-spot local pollution, such as footprint, greasy dirt, breakage etc.

In sum, existing AGV vision guided navigation scheme also exists obvious weakness: 1, the mount scheme of camera is to be installed as master vertically downward, and camera view is narrow and small, is only limitted to light shield or the very little region of AGV vehicle body, is difficult to adapt to AGV high-speed cruising; 2, the camera tilting to install, also to fixedly mount form, lacks the physical relationship expression formula of setting angle and AGV car body travelling speed, navigator fix control accuracy, field range etc.; Stitching is followed the tracks of the vertical camera of main dependence and is completed; 3, the camera tilting to install is only for predicting road ahead situation, and not direct and stitching tracing task contacts.

Utility model content

One of the utility model object is to provide a kind of self-adaptation AGV vision guided navigation sight line adjusting gear, and it is narrow and small that the utility model overcomes camera view in prior art, the shortcoming that camera angle cannot adjust.

A kind of self-adaptation AGV vision guided navigation sight line adjusting gear that the utility model provides, comprise camera, runing rest, steering wheel, bracing frame, AGV car body and wheel, support frame as described above is anchored on AGV car body, steering wheel is fixed on bracing frame, steering wheel is fixedly connected with runing rest, camera is fixed on runing rest, described camera is positioned on AGV Vehicular body front axis, camera, by the drive adjustable sight line gear angle of steering wheel, adjusts AGV car body by the corner controlling wheel and turns to.

Further, the sight line gear angle of described camera comprises 30 °, 45 °, 60 ° and 75 °.

Further, the left and right angle of visibility of described camera is 30 °.

The beneficial effects of the utility model are, the utility model can adjust the sight angle of camera automatically according to the speed of AGV car body, camera view is open, and navigator fix controls accurately, thus can increase work efficiency.

Accompanying drawing explanation

Figure 1 shows that a kind of self-adaptation AGV vision guided navigation of the utility model sight line adjusting gear structural representation.

Figure 2 shows that a kind of self-adaptation AGV vision guided navigation of the utility model sight line adjustment stitching tracking process flow diagram.

Figure 3 shows that parameters schematic diagram in a kind of self-adaptation AGV vision guided navigation of the utility model sight line adjustment stitching tracking.

Embodiment

Hereafter will describe the utility model in detail in conjunction with specific embodiments.It should be noted that the combination of technical characteristic or the technical characteristic described in following embodiment should not be considered to isolated, they can mutually be combined thus be reached better technique effect.

As shown in Figure 1, a kind of self-adaptation AGV vision guided navigation sight line adjusting gear that the utility model provides, comprise camera 1, runing rest 2, steering wheel 3, bracing frame 4, AGV car body 5 and wheel, support frame as described above 4 is anchored on AGV car body 5, steering wheel 3 is fixed on bracing frame 4, steering wheel 3 is fixedly connected with runing rest 2, camera 1 is fixed on runing rest 2, described camera 1 is positioned on the anterior axis 7 of AGV car body 5, camera 1, by the drive adjustable sight line gear angle beta of steering wheel 3, adjusts AGV car body 5 by the corner controlling wheel and turns to.

The adjustment of this device sight line is completed by adjustment forward sight camera 1 gear angle beta, relevant with the current kinetic speed of AGV car body 5.When movement velocity is lower, less sight line gear angle beta is selected to obtain higher positional precision; When movement velocity is higher, select larger sight line gear angle beta to obtain larger visual field breadth, ensure AGV car body 5 stitching pursuit movement precision.

Camera 1 sets some gear angle betas, and typical gear angle beta has 4 gears, is respectively 30 °, 45 °, 60 ° and 75 °.

As Figure 1-3, the stitching tracking of self-adaptation AGV vision guided navigation sight line adjusting gear, comprises the steps:

Step S1: put image frame sequence number i=1, accepts the instruction of AGV task scheduling and advances forward with instruction speed, arranges wheel steering angle adjustment increment initial value

Step S2: according to the feedback data of current AGV car body 5 actual motion speed v, adjustment camera 1 gear angle beta, calculate the auxiliary parameter K of current angular inferoanterior ground guiding lines 8, wherein camera 1 gear angle beta is camera sight line and pedal line angle.

When considering that β angle is larger, surface road only will can occupy down half picture, more than local horizon meaningless picture occupies half picture, get the transverse direction of guiding lines 8 in adjacent two frame continuous videos pictures or the change of longitudinal location of pixels, must not exceed second breadth of video pixel preferred value is ensure in continuous print two frame video pictures, AGV car body 5 does not have possibility to exceed the breadth size of video relative to the location variation of guiding lines 8, can correctly be caught.According to the size of current AGV car body 5 travelling speed v, adjusted the gear angle beta of camera 1 by steering wheel 3, make be not less than vT, wherein for the surface road length that second breadth height of video pictures is corresponding, T is the time of acquisition 1 frame picture.

The guiding lines 8 that the adjustment of camera 1 gear angle beta can make perspective effect cause compress to distort with other pictures and are among dynamic changing process, and therefore traditional image calibration technology will lose efficacy.Also completely in video pictures space, itself AGV stitching tracing control can only must be carried out as reference according to guiding lines 8.

Grey level histogram enhancing is carried out to video pictures, Laplace operator is adopted to extract two edges of guiding lines 8, utilize straight line Hough transformation to calculate straight-line segment starting point and the orientation angle at two edges about representative guiding lines in video pictures, get the vector mark of middle separated time 9 as guiding lines 8 of two edge lines.

Ground vertical interval between video pictures center pixel row and bottom pixel row is wherein H is the height on camera 1 rotation center distance ground, and α is the visible angle of the left rotation and right rotation of camera 1, and representative value is 30 degree.In video pictures, each pixel interval in every a line is approximate can think equal.Guiding lines 8 adopt 45 ~ 50mm width criteria light tone adhesive tape as white, yellow, pink etc., are directly pasted on dark ground and form.The number of pixels that the developed width of guiding lines 8 presents in video pictures is only relevant with camera 1 gear angle beta and camera 1 screen resolution m × n, can calculate among AGV operational process in advance.

Wherein auxiliary parameter for a constant sequence relevant with camera 1 gear angle beta, wherein d is the distance of AGV car body front-wheel 6 apart from AGV car body 5 front end, and L is the distance of AGV car body front-wheel 6 to trailing wheel 10.

Step S3: extract in the i-th-1 frame video pictures bottom line and center row two height and positions, number of pels per line amount between two edges on guiding lines 8 Width, and i-th-1 to guide in frame video pictures in lines bottom separated time 9 and picture and the horizontal sequence number of the location of pixels corresponding to two intersection points of picture central horizontal pixel column, the inclination and the position that calculate the guiding lines in the threshold value of Attitude Tracking error assessment function under current gear angle beta and picture are departed from;

Number of pels per line amount on line segment of guiding in certain frame picture on lines 8 Width between two edges is designated as iPixNum.

Grey level histogram enhancing is carried out to the i-th-1 frame video pictures, corrosion expansion process, take Hough transformation to extract edge line, extract on bottom line in first width picture and center row two height and positions, l between two edges on guiding lines 8 Width ₀with number of pels per line amount on line segment with and i-th-1 to guide in frame video pictures in lines bottom separated time 9 and picture and the horizontal sequence number iBtm and iMid of the location of pixels corresponding to two intersection points of picture central horizontal pixel column.

According to fixing certain gear angle beta, on the bottom line in certain frame picture and picture center row two height positions, calculate l on guiding lines 8 Width ₀with the every corresponding horizontal actual distance on the ground of row pixel on line segment, is designated as respectively with be recorded as the pixel column width constant under respective notch sight angle β.

In guiding lines bottom separated time 9 and picture and the horizontal sequence number of the location of pixels corresponding to two intersection points of picture central horizontal pixel column, be designated as iBtm and iMid respectively.The course angle θ of AGV, θ are the anterior axis 7 of AGV car body 5 and the angle of separated time 9 in guiding lines, meet:

$\tan \left(\mathrm{\θ}\right)=\frac{1}{h_{\frac{n}{2}}}\·[w_{\frac{n}{2}}\·(\mathrm{iMid}-\frac{n}{2})-w_0\·(\mathrm{iBtm}-\frac{n}{2})]$

In stitching tracing process, the two row location of pixels difference expression formulas of getting AGV course angle θ are dir=iMid-iBtm.According to the course angle accuracy requirement of θ≤2 °, the two row location of pixels difference limen values corresponding to course angle threshold value should be taken as dir≤ε _θ, wherein ${\mathrm{\ϵ}}_{\mathrm{\θ}}=0.0007\·h_{\frac{n}{2}}\·{\mathrm{iPixNum}}_{\frac{n}{2}}.$

In stitching tracing process, the pixel expression formula of AGV positional precision is taken as the position accuracy demand of foundation ± 20mm, the pixel threshold corresponding to AGV positional precision is taken as pos≤ε _d, wherein ε _d=0.4iPixNum ₀.

The threshold value of getting Attitude Tracking error assessment function is one less among both, both J _ε=min{ ε _θ, ε _d.

The degree of tilt of the guiding lines 8 in picture and position are departed from and are respectively: $\left\{\begin{array}{c}{\mathrm{dir}}^{(i-1)}={\mathrm{iMid}}^{(i-1)}-{\mathrm{iBtm}}^{(i-1)}\\ {\mathrm{pos}}^{(i-1)}={\mathrm{iBtm}}^{(i-1)}-\frac{n}{2}\end{array}\right..$

AGV Attitude Tracking error assessment function is made to be J=K ²dir ²+ pos ², when AGV car body 5 attitude that and if only if overlaps completely with guiding lines 8 just, tracking error J is just zero.

Step S4: AGV wheel turning angle is set to

About 10% is reduced for principle to make Attitude Tracking error assessment function J, Newton-decline method is taked to calculate AGV wheel angle adjustment amount in every frame picture, calculate with the non_derivative of the pixel change in two continuous frames picture, then the angular setting amount in the 3rd frame picture is bracket subscript (i) wherein represents the sequence number of frame of video.Every frame picture constantly adjusts wheel steering angle between switching until tracking error J is positioned within designated precision scope, ensure course error dir≤ε _θ, and positioning error pos≤ε _d, meet the threshold value J of Attitude Tracking error assessment function _ε=min{ ε _θ, ε _d.

Step S5: check AGV car body 5 current actual motion speed v, adjustment camera angle gear β, if gear β changes, then step S2 recalculate current angular inferoanterior ground guiding lines 8 auxiliary parameter K, if gear β is unchanged, then turn next step.

Step S6: extract in the i-th frame video pictures and guide bottom separated time in lines 9 and picture and the horizontal sequence number of the location of pixels corresponding to two intersection points of picture central horizontal pixel column, the degree of tilt and the position that calculate the guiding lines 8 in picture are departed from, and calculate attitude error evaluation function and evaluation function increment further.

Gather the i-th frame video pictures, grey level histogram enhancing is carried out to the i-th frame picture, corrosion expansion process, take Hough straight line to convert and extract edge line, extract iBtm ⁽ⁱ⁾, iMid ⁽ⁱ⁾.

The degree of tilt of the guiding lines 8 in picture and position depart from for $\left\{\begin{array}{c}{\mathrm{dir}}^{\left(i\right)}={\mathrm{iMid}}^{\left(i\right)}-{\mathrm{iBtm}}^{\left(i\right)}\\ {\mathrm{pos}}^{\left(i\right)}={\mathrm{iBtm}}^{\left(i\right)}-\frac{n}{2}\end{array}\right.,$ $\left\{\begin{array}{c}\mathrm{\Δ}{\mathrm{dir}}^{\left(i\right)}={\mathrm{dir}}^{\left(i\right)}-{\mathrm{dir}}^{(i-1)}\\ \mathrm{\Δ}{\mathrm{pos}}^{\left(i\right)}={\mathrm{pos}}^{\left(i\right)}-{\mathrm{pos}}^{(i-1)}\end{array}\right.;$

Attitude error evaluation function and evaluation function increment are respectively:

J ⁽ⁱ⁾＝K ²·dir ⁽ⁱ⁾·dir ⁽ⁱ⁾+pos ⁽ⁱ⁾·pos ⁽ⁱ⁾，ΔJ ⁽ⁱ⁾＝K ²·dir ⁽ⁱ⁾·Δdir ⁽ⁱ⁾+pos ⁽ⁱ⁾·Δpos ⁽ⁱ⁾。

Step S7: judge whether evaluation function increment is less than or equal to the threshold value of Attitude Tracking error assessment function, namely judge Δ J ⁽ⁱ⁾≤ J _εwhether set up, if go to step S10, otherwise turn next step.

Step S8: calculate angular setting amount frame of video sequence number i=i+1, goes to step S5 and resets AGV wheel steering angle,

Wherein angular setting amount

Step S9: judge whether Attitude Tracking error assessment function J is less than or equal to the threshold value of Attitude Tracking error assessment function, namely judges J ⁽ⁱ⁾≤ J _εwhether set up, if so, turn next step; Otherwise go to step S11.

Step S10: keep wheel steering angle constant, namely frame of video sequence number i=i+1, goes to step S4, due to namely be equivalent to go to step S5 and reexamine the current actual motion speed v of AGV car body 5, adjustment camera angle gear β.

Step S11: calculate angular setting amount frame of video sequence number i=i+1, goes to step S4 and resets AGV wheel steering angle.

Wherein angular setting amount

The utility model AGV car body 5 turns to adjustment mode to be realize with the mode constantly adjusting AGV both sides wheel differential by constantly adjusting AGV both sides wheel turning angle.So-called differential, the wheel rotor speed being exactly AGV car body 5 both sides is not identical, or rotating speed is contrary; When both sides vehicle wheel rotational speed is different, AGV car body 5 will be turned to the rotating speed wheel direction that some or reverse direction rotate slowly.

Below in conjunction with experiment checking validity of the present utility model further, experimental procedure is as follows:

Ground guide wire 8 extracting yellow standard adhesive tapes, width is 50mm, is directly pasted on dark ground.AGV car body 5 width is 380mm, wheelbase 600mm, and camera 1 is installed on axis, AGV car body 5 dead ahead 7,100mm, both d=100mm, L=600mm before being positioned at AGV front-wheel 6 axial line.Camera 1 is by steering wheel 3 Direct driver, and be in certain particular location among four fixing gear angles all the time, gear angle beta is respectively 30 °, 45 °, 60 ° and 75 °.Camera 1 setting height(from bottom) is H=300mm; Camera 1 video breadth is 640 × 480, and frame per second is 25 frames/second, and left and right angle of visibility size is α=30 °.Corresponding to different gear angles, the ground true breadth parameters value that video pictures is corresponding is in theory as shown in table 1:

Table 1: the ground that video pictures is corresponding true breadth parameters value

β	30°	45°	60°	0
					Corresponding ground width in the middle of picture	180mm	220mm	311mm	600mm
Corresponding ground width bottom picture	161mm	180mm	220mm	311mm
					To bottom corresponding ground height in the middle of picture	93mm	127mm	220mm	600mm

But due to camera 1 actual left and right angle of visibility α and out of true is 30 ° and Width and short transverse size also have difference, therefore, in upper table gross data only write as algorithm in initial value reference data is set.When real data starts according to the car body 5 of AGV described in the utility model, guiding lines 8 carry out pixel counts approximately perpendicular to the original state bottom video pictures, acquiescence line thickness is 50mm, respectively the middle row pixel in video pictures frame and bottom line number of pixels are counted, be designated as the iPixNum under current gear angle ₀with

AGV car body 5 is placed on guiding lines 8 time flat, guiding lines 8 to appear in camera picture near normal forward.AGV task scheduling system command request, starts AGV car body 5 and runs forward.The adjustment of camera 1 angle is carried out according to the current real-time speed feedback of AGV car body 5.For guaranteeing among AGV car body 5 operational process, the interframe displacement of guiding lines 8 is enough little, takes off half range face pixels tall both 24 pixels, the speed stage threshold value as camera 1 angular setting:

Work as the speed of a motor vehicle time, camera gear angular setting is set to 30 °;

Work as the speed of a motor vehicle time, camera 1 gear angular setting is set to 45 °;

Work as the speed of a motor vehicle time, camera 1 gear angular setting is set to 60 °;

Work as the speed of a motor vehicle time, camera 1 gear angular setting is set to 75 °.

Namely bring into operation after AGV car body 5 startup stitching trace routine, grey level histogram enhancing is carried out to video pictures frame, corrosion expansion process, take Hough transformation to extract edge line, respectively the picture between the edge line on picture middle position and bottom position is counted, obtain with try to achieve AGV Attitude Tracking error assessment function threshold further $J_{\mathrm{\ϵ}}=K^2\·{[0.0007\·h_{\frac{n}{2}}\·{{\mathrm{iPixNum}}_{\frac{n}{2}}}^{(i-1)}]}^2+{[0.4\·{{\mathrm{iPixNum}}_0}^{(i-1)}]}^2;$ With original speed position angle beta=30 ° and theory of correspondences value for reference, under original speed position angle beta=30 °, K=6.18, and with reference value should be respectively with corresponding J _ε=min{5100,6336}=5100.

In the process of follow-up each frame picture, every frame carries out grey level histogram enhancing, corrosion expansion process, takes Hough transformation to extract edge line, calculates $\left\{\begin{array}{c}{\mathrm{dir}}^{\left(i\right)}={\mathrm{iMid}}^{\left(i\right)}-{\mathrm{iBtm}}^{\left(i\right)}\\ {\mathrm{pos}}^{\left(i\right)}={\mathrm{iBtm}}^{\left(i\right)}-\frac{n}{2}\end{array}\right.$ With $\left\{\begin{array}{c}\mathrm{\Δ}{\mathrm{dir}}^{\left(i\right)}={\mathrm{dir}}^{\left(i\right)}-{\mathrm{dir}}^{(i-1)}\\ \mathrm{\Δ}{\mathrm{pos}}^{\left(i\right)}={\mathrm{pos}}^{\left(i\right)}-{\mathrm{pos}}^{(i-1)}\end{array}\right.,$ Further Calculation Estimation function J ⁽ⁱ⁾=K ²dir ⁽ⁱ⁾dir ⁽ⁱ⁾+ pos ⁽ⁱ⁾pos ⁽ⁱ⁾with evaluation function increment Delta J ⁽ⁱ⁾=K ²dir ⁽ⁱ⁾Δ dir ⁽ⁱ⁾+ pos ⁽ⁱ⁾Δ pos ⁽ⁱ⁾; If Δ J ⁽ⁱ⁾be greater than evaluation function threshold value J _ε, then the corner adjustment amount between image frame switching is if Δ J ⁽ⁱ⁾be less than or equal to evaluation function threshold value J _ε, then the corner adjustment amount between image frame switching is aGV car body continues to adjust wheel steering angle in operational process size, until evaluation function J ⁽ⁱ⁾≤ J _ε, show that AGV car body 5 is on correct circuit, keep wheel steering angle constant, both corner adjustment amount perseverance was zero, realized continual and steady stitching and followed the tracks of.

Although given embodiments more of the present utility model, it will be understood by those of skill in the art that when not departing from the utility model spirit herein, can change embodiment herein.Above-described embodiment is exemplary, should using embodiment herein as the restriction of the utility model interest field.

Claims (3)

1. a self-adaptation AGV vision guided navigation sight line adjusting gear, it is characterized in that, comprise camera, runing rest, steering wheel, bracing frame, AGV car body and wheel, support frame as described above is anchored on described AGV car body, described steering wheel is fixed on support frame as described above, described steering wheel is fixedly connected with described runing rest, described camera is fixed on described runing rest, described camera is positioned on described AGV Vehicular body front axis, described camera is by the drive of described steering wheel, adjustable sight line gear angle, adjust described AGV car body by the corner controlling described wheel to turn to.

2. a kind of self-adaptation AGV vision guided navigation sight line adjusting gear as claimed in claim 1, it is characterized in that, the sight line gear angle of described camera comprises 30 °, 45 °, 60 ° and 75 °.

3. a kind of self-adaptation AGV vision guided navigation sight line adjusting gear as claimed in claim 1, it is characterized in that, the left and right visible angle of described camera is 30 °.