CN219899473U - Laser cleaning system for inner wall of special-shaped pipeline - Google Patents

Abstract

The utility model relates to a laser cleaning system for the inner wall of a special-shaped pipeline, which comprises a crawling mechanism and a cleaning head which is arranged at the front end of the crawling mechanism and can rotate 360 degrees around the central axis of the crawling mechanism; the laser displacement sensor, the vibrating mirror and the zooming module are respectively and electrically connected with the upper computer; the laser displacement sensor, the vibrating mirror and the reflecting mirror are all fixed with the cleaning head; the reflecting surface of the reflecting mirror is opposite to the light outlet of the laser displacement sensor; the zooming module is fixed on the crawling mechanism, and the light outlet of the zooming module faces the light inlet of the vibrating mirror; the included angle between the measuring laser beam emitted by the laser displacement sensor and the cleaning laser beam emitted by the vibrating mirror after being reflected by the reflecting mirror is 180 degrees, and the measuring laser beam is perpendicular to the central axis of the crawling mechanism. The beneficial effects of the utility model are as follows: the measuring laser beam and the cleaning laser beam are distributed at 180 degrees, so that the measurement and the cleaning can be synchronously performed at part of time, the cleaning time is effectively shortened by 25%, and the cleaning efficiency is improved.

Description

Laser cleaning system for inner wall of special-shaped pipeline

Technical Field

The utility model relates to the field of laser cleaning of inner walls of pipelines, in particular to a laser cleaning system for inner walls of special-shaped pipelines.

Background

Some special-purpose long and narrow special-shaped pipelines can generate residual attachments on the inner wall after long-time use, and accumulation of the attachments can not only influence the overall service performance of the pipeline, but also bring certain potential safety hazards, so that the attachments in the pipeline need to be cleaned. The traditional pipeline inner wall generally adopts artifical sandblast to polish or the mode of chemistry to wash, and this kind of cleaning mode does not possess the maneuverability under the small pipe diameter condition owing to receive the space restriction on the one hand, and on the other hand adopts traditional washing can't accomplish the washing of refining, and can cause irreversible damage to pipeline inner wall substrate, leads to pipeline whole life to reduce.

The laser cleaning technology based on the pipeline robot has considerable advantages in the aspect of cleaning the inner wall of the pipeline, not only solves the problem of narrow space of the pipeline, but also can clean the inner wall of the pipeline in a refined way without damaging the inner wall of the pipeline.

At present, related technical achievements are applied to laser cleaning of the inner wall of a pipeline, but the laser cleaning can only adapt to a regular circular pipeline, and the laser cleaning device has no ability to clean a special-shaped pipeline. For the laser cleaning of special-shaped pipelines, the primary condition is that the problem of real-time zooming in the cleaning process is solved, if the special-shaped pipeline is a pipeline with a known inner contour, the pipeline form data auxiliary zooming can be directly called, but for the pipeline after long-time use, certain deformation can occur, so that the inner wall of the pipeline is measured firstly, and the auxiliary zooming is carried out by using the measured data.

Disclosure of Invention

The technical problem to be solved by the utility model is to provide a laser cleaning system for the inner wall of a special-shaped pipeline, so as to overcome the defects in the prior art.

The technical scheme for solving the technical problems is as follows: a laser cleaning system for an inner wall of a profiled conduit, comprising: the cleaning head is arranged at the front end of the crawling mechanism and can rotate 360 degrees around the central axis of the crawling mechanism; further comprises: the laser displacement sensor, the vibrating mirror and the zooming module are respectively and electrically connected with the upper computer; the laser displacement sensor, the vibrating mirror and the reflecting mirror are all fixed with the cleaning head; the reflecting surface of the reflecting mirror is opposite to the light outlet of the laser displacement sensor; the zooming module is fixed on the crawling mechanism, and the light outlet of the zooming module faces the light inlet of the vibrating mirror; the included angle between the measuring laser beam emitted by the laser displacement sensor and the cleaning laser beam emitted by the vibrating mirror after being reflected by the reflecting mirror is 180 degrees, and the measuring laser beam is perpendicular to the central axis of the crawling mechanism.

The beneficial effects of the utility model are as follows:

1) The inner wall of the deformed special-shaped pipeline can be effectively cleaned by measuring the inner wall of the pipeline by means of the laser displacement sensor and utilizing the measurement data to assist in cleaning and zooming;

2) The measuring laser beam and the cleaning laser beam are distributed at 180 degrees, so that the front half circle can be measured firstly, then the front half circle is cleaned, meanwhile, the rear half circle is measured, after the cleaning of the front half circle is completed, the measuring work of the rear half circle is completed, and the cleaning of the rear half circle can be continued, so that the measuring and the cleaning can be synchronously performed at part of time, the cleaning time is effectively shortened by 25%, and the cleaning efficiency is improved;

3) Because the measuring laser beam and the cleaning laser beam are distributed at 180 degrees, the interference of the reflected light of the laser cleaning beam to the laser displacement sensor is avoided, so that the laser displacement sensor can accurately measure distance, more accurate focusing is facilitated, and the cleaning device is better suitable for cleaning the inner wall of the special-shaped pipeline.

On the basis of the technical scheme, the utility model can be improved as follows.

Further, the laser displacement sensor, the reflecting mirror and the vibrating mirror are arranged inside the cleaning head, a measuring window and a cleaning window are arranged at corresponding positions on the outer wall of the cleaning head, and the measuring window and the cleaning window are 180-degree symmetrical.

The adoption of the method has the further beneficial effects that: the laser displacement sensor, the reflecting mirror and the vibrating mirror are arranged inside the cleaning head, so that the cleaning head can be protected, damage is avoided, and dust in the cleaning process is prevented from affecting the measurement and cleaning precision.

Further, the cleaning head includes: the device comprises a fulcrum, an outer cover, a rotating motor, a grating disk and a photoelectric switch, wherein the fulcrum is hollow, one end of the fulcrum is fixed with a crawling mechanism, the outer cover is sleeved at the other end of the fulcrum, the outer cover is rotationally connected with the fulcrum, the grating disk is arranged in the outer cover, the grating disk is coaxially fixed with the fulcrum, the photoelectric switch is fixed in the outer cover, the photoelectric switch is matched with the grating disk, the photoelectric switch obtains the rotating angle of a cleaning head in a counting mode, the rotating motor is fixed in the outer cover, a gear transmission is adopted between a main shaft and the fulcrum of the rotating motor, and the rotating motor and the photoelectric switch are respectively and electrically connected with an upper computer.

Further, 360 light-passing holes are distributed on the annular belt of the grating disk at equal intervals, wherein the widths of 358 light-passing holes are 0.18mm, the widths of the remaining two light-passing holes are 0.12mm, and the two light-passing holes with the widths of 0.12mm are symmetrically distributed on the circumference at 180 degrees.

The beneficial effects of adopting the two steps are that: the rotation angle can be accurately measured so as to accurately control the cleaning and measured switching time.

Further, the zoom module includes: the zoom motor, the movable zoom lens and the fixed zoom lens are both fixed inside the crawling mechanism, the movable zoom lens is fixedly connected with the zoom motor, and the zoom motor is electrically connected with the upper computer.

The adoption of the method has the further beneficial effects that: the movable zoom lens can move back and forth along the optical axis through the zoom motor, so that the distance between the movable zoom lens and the fixed zoom lens is changed, the focal length of the optical path is changed, and finally the focusing distance of the laser beam is changed.

Further, the method further comprises the following steps: the QCS interface is arranged at the tail end of the crawling mechanism, the zooming module is arranged between the QCS interface and the supporting shaft, and the laser beam emitted in the QCS interface coincides with the zooming optical path optical axis of the zooming module.

Further, a light barrier is arranged on the outer side of the crawling mechanism; further comprises: the ranging port of the laser ranging sensor faces the light barrier, and the laser ranging sensor is electrically connected with the upper computer.

The adoption of the method has the further beneficial effects that: the light barrier can receive ranging light spots of the tail laser ranging sensor, and then closed-loop control of the crawling mechanism is realized through ranging data of the laser ranging sensor.

Drawings

FIG. 1 is a block diagram of a laser cleaning system for the inner wall of a special-shaped pipeline according to the utility model;

FIG. 2 is a layout diagram of the present utility model relating to measurement and cleaning;

FIG. 3 is a block diagram of a grating disk according to the present utility model;

FIG. 4 is an enlarged view of FIG. 3 at A;

fig. 5 is an enlarged view at B in fig. 3.

In the drawings, the list of components represented by the various numbers is as follows:

1. the device comprises a crawling mechanism, 2, a cleaning head, 210, a supporting shaft, 220, a housing, 221, a measuring window, 222, a cleaning window, 230, a rotating motor, 240, a grating disk, 250, a photoelectric switch, 3, a laser displacement sensor, 4, a reflecting mirror, 5, a vibrating mirror, 6, a zooming module, 610, a zooming motor, 620, a movable zooming lens, 630, a fixed zooming lens, 7, a QCS interface, 8, a light barrier, 9 and a laser ranging sensor.

Detailed Description

The principles and features of the present utility model are described below with reference to the drawings, the examples are illustrated for the purpose of illustrating the utility model and are not to be construed as limiting the scope of the utility model.

Example 1

As shown in fig. 1 and 2, a laser cleaning system for an inner wall of a special-shaped pipeline includes: the device comprises a crawling mechanism 1, a cleaning head 2, a laser displacement sensor 3, a reflecting mirror 4, a vibrating mirror 5, a zooming module 6 and an upper computer;

the signal output of the laser displacement sensor 3 is electrically connected with the signal input of the upper computer, the signal input of the zoom module 6 is electrically connected with the signal output of the upper computer, the signal input of the cleaning head 2 is electrically connected with the signal output of the upper computer, and the vibrating mirror 5 can also be electrically connected with the upper computer;

the cleaning head 2 is arranged at the front end of the crawling mechanism 1, and the cleaning head 2 can rotate 360 degrees around the central axis of the crawling mechanism 1;

the laser displacement sensor 3 is fixed with the cleaning head 2, the vibrating mirror 5 is also fixed with the cleaning head 2, the reflecting mirror 4 is fixed with the cleaning head 2, the reflecting surface of the reflecting mirror 4 is opposite to the light outlet of the laser displacement sensor 3, and when the cleaning head 2 starts to rotate around the central axis of the crawling mechanism 1, the laser displacement sensor 3, the reflecting mirror 4 and the vibrating mirror 5 rotate along with each other;

the measuring laser beam emitted by the laser displacement sensor 3 is reflected by the reflecting mirror 4 and then irradiates on the inner wall of the special-shaped pipeline, and in the embodiment, the reflecting mirror 4 is arranged at an angle of 45 degrees; the cleaning laser after zooming by the zooming module 6 enters the vibrating mirror 5 and then is emitted out, and in the process, a focusing light spot can be in a line scanning mode on the inner wall of a pipeline through high-frequency vibration of the vibrating mirror 5, and the scanning line direction is parallel to the central axis of the crawling mechanism 1;

the included angle between the measuring laser beam emitted by the laser displacement sensor 3 after being reflected by the reflecting mirror 4 and the cleaning laser beam emitted by the vibrating mirror 5 is 180 degrees, the measuring laser beam emitted by the laser displacement sensor 3 after being reflected by the reflecting mirror 4 is vertical to the central axis of the crawling mechanism 1, and the cleaning laser beam emitted by the vibrating mirror 5 is vertical to the central axis of the crawling mechanism 1.

Example 2

As shown in fig. 1 and 2, this embodiment is a further improvement on the basis of embodiment 1, and is specifically as follows:

the laser displacement sensor 3, the reflecting mirror 4 and the vibrating mirror 5 are arranged inside the cleaning head 2, a measuring window 221 and a cleaning window 222 are arranged at corresponding positions on the outer wall of the cleaning head 2, and the measuring window 221 and the cleaning window 222 are symmetrical at 180 degrees;

the measuring laser beam emitted by the laser displacement sensor 3 is reflected by the reflecting mirror 4 and then emitted from the measuring window 221 to reach the inner wall of the pipeline, so that the measurement of the inner wall of the pipeline is completed;

the cleaning laser beam emitted from the vibrating mirror 5 is emitted through the cleaning window 222 and finally focused on the inner wall of the pipeline so as to clean the inner wall of the pipeline;

the laser displacement sensor 3, the reflecting mirror 4 and the vibrating mirror 5 are arranged inside the cleaning head 2, so that the cleaning head can be protected from damage and dust in the cleaning process from affecting the measurement and cleaning precision.

Example 3

As shown in fig. 1 and 3, this embodiment is a further improvement on the basis of embodiment 1 or 2, and is specifically as follows:

the cleaning head 2 includes: fulcrum 210, housing 220, rotary motor 230, grating disk 240, and photoelectric switch 250; the fulcrum 210 is hollow, that is, the fulcrum 210 is a through shaft, the central axis of the fulcrum 210 is collinear with the central axis of the crawling mechanism 1, one end of the fulcrum 210 is fixed with the crawling mechanism 1, the other end of the fulcrum 210 is sleeved with the outer cover 220, the outer cover 220 is rotationally connected with the fulcrum 210, and the outer cover 220 and the fulcrum 210 can be rotationally connected through bearings;

the grating disk 240 is disposed in the housing 220, the grating disk 240 is coaxially fixed with the support shaft 210, the photoelectric switch 250 is fixed in the housing 220, the photoelectric switch 250 is matched with the grating disk 240, and the photoelectric switch 250 obtains the rotation angle of the cleaning head 2 in a counting manner, which can be specifically understood as: the edge of the grating disk 240 is in the optical path of the photoelectric switch 250, when the photoelectric switch 250 rotates around the grating disk 240 along with the outer cover 220, the optical path of the photoelectric switch 250 is conducted when passing through the light passing hole of the grating disk 240, and is blocked when passing through the non-light passing hole area, and the rotation angle of the photoelectric switch 250 around the grating disk 240 can be known through alternating conduction and blocking, which is the rotation angle of the corresponding cleaning head 2, and in general, the photoelectric switch 250 can count in a 1ms time interval manner;

the rotating motor 230 is fixed in the outer cover 220, and gear transmission is adopted between the main shaft of the rotating motor 230 and the support shaft 210, namely the rotating motor 230 is started, and 360-degree rotation around the support shaft 210 can be realized by means of gear transmission so as to meet the measurement and cleaning requirements; the gear transmission can be realized by the following specific structure: comprises a driving gear and a driven gear, wherein the driving gear is fixed on a main shaft of the rotating motor 230, the driven gear is fixedly sleeved on the support shaft 210, and the driving gear is meshed with the driven gear;

the signal output of the photoelectric switch 250 is electrically connected to the signal input of the host computer, and the signal input of the rotary motor 230 is electrically connected to the signal output of the host computer.

Example 4

As shown in fig. 3, 4 and 5, this embodiment is a further improvement on the basis of embodiment 3, and is specifically as follows:

360 light-passing holes are distributed in the annular belt of the grating disk 240 at equal intervals, wherein the widths of 358 light-passing holes are 0.18mm, the widths of the remaining two light-passing holes are 0.12mm, and the two light-passing holes with the widths of 0.12mm are symmetrically distributed on the circumference at 180 degrees.

Example 5

As shown in fig. 1, this embodiment is a further improvement on the basis of embodiment 3 or 4, and is specifically as follows:

the zoom module 6 includes: the zoom motor 610, the movable zoom lens 620 and the fixed zoom lens 630, the zoom motor 610 is fixed inside the crawling mechanism 1, the fixed zoom lens 630 is fixed inside the crawling mechanism 1, the movable zoom lens 620 is fixedly connected with the zoom motor 610, the zoom motor 610 is electrically connected with an upper computer, the movable zoom lens 620 can be moved back and forth along the optical axis through the zoom motor 610, and therefore the distance between the movable zoom lens 620 and the fixed zoom lens 630 is changed, the focal length of an optical path is changed, and finally the focusing distance of a laser beam is changed.

Of course, the specific structure of the zoom module 6 is not limited thereto, and may be other structures.

Example 6

As shown in fig. 1, this embodiment is a further improvement on the basis of embodiment 5, and is specifically as follows:

the special-shaped pipeline inner wall laser cleaning system also comprises: the QCS interface 7, QCS interface 7 sets up at crawling mechanism 1 tail end, zoom module 6 is located between QCS interface 7 and the fulcrum 210, the laser beam that the interior outgoing of QCS interface 7 and the zoom light path optical axis coincidence of zoom module 6, QCS interface 7 then passes through the fiber connection laser, the washing laser that the laser launched is transmitted to QCS interface 7 through the optic fibre, the laser that the outgoing of QCS interface 7 and crawling mechanism 1 axis coincidence, get into in the galvanometer 5 after passing through zoom module 6, then follow wash window 222 and jet after being reflected by galvanometer 5, finally focus on the pipeline inner wall.

Example 7

As shown in fig. 1, this embodiment is a further improvement on any one of embodiments 1 to 6, and specifically includes the following:

the outside of the crawling mechanism 1 is provided with a light barrier 8; further comprises: the laser ranging sensor 9, the ranging port of the laser ranging sensor 9 faces the light barrier 8, and the laser ranging sensor 9 is electrically connected with the upper computer; the light barrier 8 can receive the ranging light spots of the tail laser ranging sensor 9, and then the closed-loop control of the crawling mechanism 1 is realized through the ranging data of the laser ranging sensor 9.

The center of the reflecting mirror 4 and the center of the vibrating mirror 5 are positioned at the same height, and the distance between the centers of the reflecting mirror 4 and the vibrating mirror 5 is L1 = 10mm, and the distance between the light outlet of the laser displacement sensor 3 and the center of the reflecting mirror 4 is L2 = 30mm;

the laser displacement sensor 3 measures data as L (θ) at any angle when the cleaning head 2 rotates, and the distance between the center of the vibrating mirror 5 and the measuring point at the angle is L' (θ) =l (θ) -l2+l1;

the laser cleaning method for the inner wall of the special-shaped pipeline comprises the following steps:

s1, placing equipment into a pipeline, powering on the equipment, and performing self-inspection;

s2, parameter setting is carried out on the upper computer, and the following assumption is made: setting a cleaning step length DeltaL=48 mm, a galvanometer scanning width S=50 mm, a head rotating speed v=2 rpm, a sampling frequency f=100 Hz of a laser displacement sensor 3, a cleaning starting point position of a pipeline, and a pipeline cleaning length (the starting point position and the cleaning length are set according to actual working conditions);

s3, after the parameter setting is completed, starting the cleaning work, moving the crawling mechanism 1 to a cleaning starting point position, and stopping crawling;

s4, starting to rotate the cleaning head 2 at a rotating speed of 2rpm, and when the measuring window 221 rotates to a starting position (one of two light transmission holes with the width of 0.12mm is used as A, the other one is used as B, and the other one is used as A or B) marked by the grating disk 240, acquiring the section profile data of the pipeline at a frequency of 100Hz by the laser displacement sensor 3, and uploading the section profile data to an upper computer for storage in real time;

s5, when the cleaning head 2 rotates 180 degrees, the measuring window 221 rotates to a second starting position (B or A) marked by the grating disk 240, the laser displacement sensor 3 finishes the measurement of the first half circle, at the moment, the cleaning window 222 just reaches the first starting position (A or B), the laser emits light at the moment, and the cleaning laser finally emits on the inner wall of the pipeline through the vibrating mirror 5, so that the cleaning of the first half circle in the pipeline can be started;

s6, when the front half circle is cleaned, the front half circle outline measurement data stored in the upper computer are called in real time, and zooming is carried out through the zooming module 6, so that the cleaning laser beam can be accurately focused on the inner wall of the pipeline when the cleaning window 222 rotates to any angle;

s7, while the front half circle is rotated and cleaned, the laser displacement sensor 3 continuously measures the inner wall of the pipeline in the rear half circle at the frequency of 100Hz, and the measured data in the rear half circle is stored in the upper computer;

s8, after 360-degree rotation, when the measurement window 221 returns to the first starting position (A or B) marked by the grating disk 240 again, the cleaning window 222 reaches the second starting position (B or A) marked by the grating disk 240, the cleaning of the second half circle is started, the profile data of the second half circle stored in the upper computer is called in real time, and zooming is performed through the zooming module 6;

s9, when the second half circle is cleaned, the laser displacement sensor 3 stops working;

s10, when the cleaning window 222 returns to the first starting position (A or B) marked by the grating disk 240, cleaning of a section with the width of 50mm of the inner wall of the pipeline is completed;

s11, the upper computer controls the crawling mechanism 1 to crawl forward by delta L (the distance measurement is completed by the cooperation of the light barrier 8 and the laser ranging sensor 9), and the next section is entered for cleaning;

s12, reciprocating until the set pipeline cleaning length is finished;

s13, after the cleaning is finished, the upper computer controls the crawling mechanism 1 to reset, and the crawling mechanism 1 exits the pipeline;

s14, finishing cleaning.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Claims (7)

1. A laser cleaning system for an inner wall of a profiled conduit, comprising: the utility model provides a mechanism (1) and setting are crawling mechanism (1) front end and can carry out 360 rotatory cleaning head (2) around mechanism (1) axis of crawling, its characterized in that still includes: the device comprises a reflecting mirror (4), an upper computer, a laser displacement sensor (3), a vibrating mirror (5) and a zooming module (6), wherein the laser displacement sensor, the vibrating mirror (5) and the zooming module are respectively and electrically connected with the upper computer; the laser displacement sensor (3), the vibrating mirror (5) and the reflecting mirror (4) are all fixed with the cleaning head (2); the reflecting surface of the reflecting mirror (4) is opposite to the light outlet of the laser displacement sensor (3); the zooming module (6) is fixed on the crawling mechanism (1), and a light outlet of the zooming module (6) faces to a light inlet of the vibrating mirror (5); the included angle between the measuring laser beam emitted by the laser displacement sensor (3) and the cleaning laser beam emitted by the vibrating mirror (5) after being reflected by the reflecting mirror (4) is 180 degrees, and the measuring laser beam is perpendicular to the central axis of the crawling mechanism (1).

2. The laser cleaning system for the inner wall of the special-shaped pipeline according to claim 1, wherein the laser displacement sensor (3), the reflecting mirror (4) and the vibrating mirror (5) are all arranged inside the cleaning head (2), a measuring window (221) and a cleaning window (222) are formed in corresponding positions on the outer wall of the cleaning head (2), and the measuring window (221) and the cleaning window (222) are symmetrical at 180 degrees.

3. A system for laser cleaning of the inner walls of profiled tubes according to claim 1, characterised in that the cleaning head (2) comprises: fulcrum (210), dustcoat (220), rotating electrical machines (230), grating dish (240) and photoelectric switch (250), the inside cavity of fulcrum (210), the one end of fulcrum (210) with crawling mechanism (1) is fixed mutually, dustcoat (220) are established to the other end cover of fulcrum (210), dustcoat (220) with fulcrum (210) rotate and be connected, grating dish (240) are arranged in dustcoat (220), grating dish (240) with fulcrum (210) coaxial fixation, photoelectric switch (250) are fixed in dustcoat (220), photoelectric switch (250) looks adaptation with grating dish (240), photoelectric switch (250) obtain the rotation angle of cleaning head (2) with the mode of count, rotating electrical machines (230) are fixed in dustcoat (220), adopt gear drive between the main shaft of rotating electrical machines (230) with fulcrum (210), rotating electrical machines (230) and photoelectric switch (250) respectively with host computer electromechanical connection.

4. A laser cleaning system for the inner wall of a special-shaped pipeline according to claim 3, wherein 360 light-passing holes are distributed in the annular band of the grating disk (240) at equal intervals, wherein the width of 358 light-passing holes is 0.18mm, the width of the remaining two light-passing holes is 0.12mm, and the two light-passing holes with the width of 0.12mm are symmetrically distributed on the circumference at 180 degrees.

5. A special-shaped pipeline inner wall laser cleaning system according to claim 3, wherein the zoom module (6) comprises: the zoom motor (610), the movable zoom lens (620) and the fixed zoom lens (630), the zoom motor (610) and the fixed zoom lens (630) are both fixed inside the crawling mechanism (1), the movable zoom lens (620) is fixedly connected with the zoom motor (610), and the zoom motor (610) is electrically connected with an upper computer.

6. A laser cleaning system for the inner wall of a profiled conduit as claimed in claim 3, further comprising: the QCS interface (7), QCS interface (7) set up crawling mechanism (1) tail end, zoom module (6) are located QCS interface (7) with between fulcrum (210), the laser beam that the interior emergent of QCS interface (7) with zoom optical path optical axis coincidence of zoom module (6).

7. The laser cleaning system for the inner wall of the special-shaped pipeline according to claim 1, wherein a light barrier (8) is arranged on the outer side of the crawling mechanism (1); further comprises: the laser ranging sensor (9), the range finding mouth of laser ranging sensor (9) is opposite to the barn door (8), laser ranging sensor (9) with host computer electricity is connected.