CN212276263U

CN212276263U - Automatic control system for frame beam

Info

Publication number: CN212276263U
Application number: CN202021959362.0U
Authority: CN
Inventors: 周平; 姚笛; 刘景红; 刘昌义; 杜权; 傅少华; 罗冬春; 张少平; 吴小勇; 林树奎; 詹光善; 贺太金; 陈强; 赵洵; 孙泽
Original assignee: China Communications 2nd Navigational Bureau 2nd Engineering Co Ltd
Current assignee: China Communications 2nd Navigational Bureau 2nd Engineering Co Ltd
Priority date: 2020-09-09
Filing date: 2020-09-09
Publication date: 2021-01-01
Anticipated expiration: 2030-09-09

Abstract

The utility model provides a frame roof beam automatic control system, include: the RTK receiver is arranged beside a winch of a beam erecting equipment crown block and used for positioning the spatial coordinates of the crown block; the lifting height encoder is arranged on a main shaft of a winch of a crown block of the beam erecting equipment and used for positioning a space coordinate of a lifting appliance; the main beam control station is arranged in an operation chamber of the beam erecting equipment and is in communication connection with the RTK receiver and the lifting height encoder; the main beam control station is used for receiving the space coordinates of the crown block and the space coordinates of the lifting appliance; automatically generating a beam erecting scheme and sending a beam erecting instruction; the overhead traveling crane control station is arranged on the transverse moving trolley of the overhead traveling crane of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the lifting, transverse moving and longitudinal moving of the lifting appliance; and the support leg control station is arranged on the support leg of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the complete machine transverse movement of the support leg. The utility model discloses the frame roof beam that exists among the prior art can be solved and efficiency is lower when adopting manual operation to erect, makes mistakes easily, leads to the technical problem of incident.

Description

Automatic control system for frame beam

Technical Field

The utility model relates to a highway, railway bridge engineering construction technical field, concretely relates to frame roof beam automatic control system.

Background

In highway and railway engineering, when bridge construction is carried out, along with increasing requirements on bridge assembly, more and more bridge engineering is constructed by adopting a precast beam field installation process. Most of precast beams are installed on site by adopting a bridge girder erection machine, but the automatic control level of the existing bridge girder erection machine is very low, and the operation of girder erection almost completely depends on manual control of people. For the working condition of girder erection with a complex process, more operators are needed to work in a cooperative way when manual operation is adopted, the erection efficiency is low, errors are easy to occur, and safety accidents are caused.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model provides a frame roof beam automatic control system to it is lower to solve the frame roof beam that exists among the prior art and erect efficiency when adopting manual operation, makes mistakes easily, leads to the technical problem of incident.

The utility model adopts the technical proposal that an automatic control system for beam erection is provided;

in a first implementation, the method includes:

the RTK receiver is arranged beside a winch of a beam erecting equipment crown block and used for positioning the spatial coordinates of the crown block;

the lifting height encoder is arranged on a main shaft of a winch of a crown block of the beam erecting equipment and used for positioning a space coordinate of a lifting appliance;

the main beam control station is arranged in an operation chamber of the beam erecting equipment and is in communication connection with the RTK receiver and the lifting height encoder; the main beam control station comprises a control platform, and the control platform is used for receiving the space coordinates of the crown block and the space coordinates of the lifting appliance; the system is also used for automatically generating a beam erecting scheme according to the overhead travelling crane space coordinate, the lifting appliance space coordinate and the beam erecting control boundary condition and sending a beam erecting instruction;

the overhead traveling crane control station is arranged on the transverse moving trolley of the overhead traveling crane of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the lifting, transverse moving and longitudinal moving of the lifting appliance according to a beam erecting instruction; and

and the support leg control station is arranged on the support leg of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the complete machine transverse movement of the support leg according to a beam erecting instruction.

In combination with the first implementable manner, in a second implementable manner, the girder erection equipment is a bridge girder erection machine, the crown block comprises a front crown block and a rear crown block, and the support legs comprise front support legs and middle support legs.

In combination with the second implementation manner, in a third implementation manner, there are 2 RTK receivers respectively disposed beside the winches of the front and rear crown blocks of the bridge girder erection machine.

In combination with the second implementation manner, in a fourth implementation manner, the number of the hoisting height encoders is 2, and the hoisting height encoders are respectively arranged on the main shafts of the windlass of the front overhead crane and the rear overhead crane of the bridge girder erection machine.

In combination with the second implementable manner, in a fifth implementable manner, the front leg control station and the middle leg control station are respectively provided with 1 traverse stroke encoder.

With reference to the first implementable manner, in a sixth implementable manner, the safety protection device further includes:

the inclination angle sensor is placed on the precast beam piece;

the anti-collision indicating equipment is arranged at two ends of the precast beam piece; and

and the load sensor is arranged on the overhead travelling crane.

With reference to the sixth implementable manner, in a seventh implementable manner, the anti-collision indicating device is an ultrasonic anti-collision switch.

With reference to the sixth implementable manner, in an eighth implementable manner, the safety device further includes an RFID locating device, where the RFID locating device includes:

the RFID position reader is arranged on the overhead travelling crane;

the label is arranged on the main beam;

a traverse carriage encoder installed on a traverse carriage of the overhead traveling crane, an

And the longitudinal moving trolley encoder is arranged on a longitudinal moving trolley of the crown block.

In combination with the eighth implementable mode, in the ninth implementable mode, the main beam control station is provided with an audible and visual alarm.

In combination with the first, fifth or eighth implementable manner, in a tenth implementable manner, the lifting height encoder, the traverse stroke encoder, the traverse trolley encoder and the traverse trolley encoder select absolute value encoders.

According to the above technical scheme, the utility model discloses a beneficial technological effect as follows:

1. the automatic control system for the beam erection can realize the automatic control of the process that the precast beam piece is lifted away from the beam transporting vehicle until the precast beam piece is installed in place, reduce the labor consumption, and improve the installation efficiency and the one-time installation success rate.

2. By using the safety protection device, the inclination of the precast beam piece, the impact of the precast beam piece and the bent cap and the overlarge RTK positioning deviation in the beam erecting process can be avoided, the safety protection effect in the construction process is effectively improved, and the possibility of safety accidents is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

Fig. 1 is a schematic view of a bridge girder erection machine according to embodiment 1 of the present invention;

fig. 2 is a schematic diagram of the distribution of control sensors according to embodiments 1 and 2 of the present invention;

FIG. 3 is a schematic view of an underbridge feed beam according to embodiment 1 of the present invention;

fig. 4 is a schematic view of the bridge girder erection machine in place and starting to hoist according to embodiment 1 of the present invention;

fig. 5 is a schematic view of a beam hoisting process in embodiment 1 of the present invention;

fig. 6 is a schematic view of a single-side lifting of a beam body according to embodiment 1 of the present invention;

fig. 7 is a schematic view of the inclined horizontal movement of the beam body according to embodiment 1 of the present invention;

fig. 8 is a schematic view of the other side of the beam body of embodiment 1 of the present invention lifting on one side;

fig. 9 is a schematic view of the whole backward movement of the beam piece according to embodiment 1 of the present invention.

Reference numerals:

11-front crown block, 12-rear crown block, 13-front leg, 14-middle leg, 15-tail leg, 16-bracket, 17-sling, 18-sling, 21-front crown block, 24-inclination sensor, 25-anti-collision indicating equipment, 26-load sensor, 27-RFID position reader, 28-traversing car encoder, 29-longitudinally moving car encoder, 31-precast beam piece, 32-pier body and 33-cover beam.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.

Example 1

The utility model provides a frame roof beam automatic control system, include:

the RTK receiver 21 is arranged beside a winch of a crown block of the beam erecting equipment and used for positioning the spatial coordinates of the crown block;

a hoisting height encoder 22, which is arranged on a main shaft of a winch of a crown block of the beam erecting equipment and is used for positioning a space coordinate of a lifting appliance;

the main beam control station is arranged in an operation chamber of the beam erecting equipment and is in communication connection with the RTK receiver 21 and the lifting height encoder 22; the main beam control station comprises a control platform, and the control platform is used for receiving the space coordinates of the crown block and the space coordinates of the lifting appliance; the system is also used for automatically generating a beam erecting scheme according to the overhead travelling crane space coordinate, the lifting appliance space coordinate and the beam erecting control boundary condition and sending a beam erecting instruction;

the overhead traveling crane control station is arranged on the transverse moving trolley of the overhead traveling crane of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the lifting, transverse moving and longitudinal moving of the lifting appliance 17 according to a beam erecting instruction; and

The working principle of example 1 is explained in detail below:

in the embodiment, an RTK positioning technology based on a satellite positioning system is selected to measure the spatial position and the attitude of the suspended precast beam. The RTK is a real-time dynamic carrier phase differential technology, and the principle is that the carrier phase acquired by a reference station is sent to a user receiver through a differential mode of processing the observed quantity of the carrier phases of two measuring stations in real time, and the difference is calculated to calculate coordinates. The selection of the satellite positioning system is not limited, and examples in this embodiment include, for example, beidou and GPS. At the installation site, the data of the structures and the precast beam pieces finally installed in place are known through design paper files or acceptance data, and the relevant coordinates of the precast beam pieces in the beam erecting process and the final positions can be input into the beam erecting automatic control system of the embodiment to be used as target values required during installation.

As shown in FIG. 1, since the hanger 17 is located below the main structure of the bridge girder erection machine, it is easy to be shielded, and if the RTK receiver 21 is installed on the hanger 17, the measurement accuracy is easily affected. Therefore, in this embodiment, as shown in fig. 2, 1 RTK receiver 21 is respectively installed beside the windlass of the front and rear crown blocks of the bridge girder erection machine, so that the spatial coordinate positions of the front and rear crown blocks can be located, and the location accuracy can reach centimeter level. The hoisting height encoders 22 are respectively mounted on the main shafts of the windlasses of the front crown block and the rear crown block, so that the distance between the lifting appliance 17 and the RTK receiver 21 in the vertical direction can be accurately measured, and the space coordinate of the lifting appliance can be positioned. In this embodiment, the hoisting height encoder 22 is an absolute value encoder, which determines the encoding from the mechanical position without memorizing or finding a reference point, and has high anti-interference characteristics and data reliability, and the positioning accuracy can reach millimeters. Based on the measurement, the accurate space positions of the two lifting appliances can be known, the space position and the posture of the lifted object are accurately measured, and the measurement accuracy can reach centimeter level. The RTK receiver 21 and the hoisting encoder 22 are mounted in a non-limiting manner, and in the present embodiment, the mounting manner is selected as a bolt connection manner, for example.

During the construction of the beam, the length of the lifting rope 18 and the position of the hanging point of the lifting rope 18 on the longitudinal distance of the precast beam piece 31 need to be determined; the data of the structures (pier columns, capping beams and the like) on the construction site and the data of the precast beam pieces 31 to be erected adopt the data of actual acceptance, and the data form the boundary condition of beam erection control; the coordinate position where the precast beam piece 31 is finally mounted in place is used as a target value for the girder control. The data are recorded into the control platform of the automatic beam erection control system in the embodiment, and the control platform automatically generates a scheme for erecting the precast beam piece 31 according to the data, so that the line in the erecting process is clear, any structure is not touched, and finally the precast beam piece is accurately positioned. The scheme for erecting the precast beam piece 31 is automatically generated, and in this embodiment, a routing optimization algorithm may be adopted.

In this embodiment, a wireless distributed control method based on a local area network is adopted for issuing the erection instruction of the precast beam segment, and the precast beam segment is divided into a main beam control station, a front overhead traveling crane control station 11, a rear overhead traveling crane control station 12, a front leg control station 13, and a middle leg control station 14. The main beam control station serves as a main station, and the front overhead traveling crane control station 11, the rear overhead traveling crane control station 12, the front support leg control station 13 and the middle support leg control station 14 serve as sub-stations. The control platform of the main station receives an operation instruction of a remote controller, receives a space coordinate of a crown block and a space coordinate of a lifting appliance, receives state signals of safety limit detection annunciators of all the substations, automatically generates a beam erecting scheme according to the space coordinate of the crown block, the space coordinate of the lifting appliance and a beam erecting control boundary condition, generates a correct beam erecting operation instruction according to control logic, sends the beam erecting operation instruction to all the substations, and executes corresponding operation actions according to the beam erecting operation instruction. After distributed control is adopted, only power lines need to be arranged between the main station and the substation. And each substation controls and drives, and detection and control are completed in the substation nearby. In order to simplify wiring, the local area network adopts the wireless industrial network bridge to replace network cable wiring, so that the wiring construction difficulty of the bridge girder erection machine is greatly reduced, and the maintenance cost of subsequent use of the bridge girder erection machine is also reduced.

And a control platform is arranged at the master station and can display the current operation instruction through a human-computer interaction interface. When the operation is carried out, all fault information of the whole machine can be displayed, and maintenance personnel can conveniently overhaul the equipment.

The master station and the slave station are described in detail below:

the main beam control station is arranged in an operating room of the bridge girder erection machine, in particular to a cab at the tail part of the bridge girder erection machine. The master station receives an operation instruction from the line control remote controller and generates a control instruction according to signals (including safety limit, overload, state and the like) detected and fed back by the substation; meanwhile, various operation information and fault information are displayed on a human-computer interface of the control platform in real time. The hydraulic control of the tail leg 15 is directly controlled by the master station. The front crown block, the rear crown block, the front supporting leg and the middle supporting leg act, and the driving control is completed by each substation. The master station is responsible for distributing power for each substation besides performing control functions.

The front crown block control station 11 and the rear crown block control station 12 are arranged on a transverse trolley of a crown block of the bridge girder erection machine, are electrically connected with the main beam control station (including power supply and communication), are used for controlling lifting, transverse movement and longitudinal movement of a lifting appliance 17, and specifically adopt a driving mode of frequency conversion and speed regulation. The linkage of two overhead traveling cranes runs synchronously and is coordinated and controlled by a main station, and the master-slave relationship and the control relationship are not involved between two substations.

Because the two support legs, namely the front support leg of the bridge girder erection machine and the middle support leg of the bridge girder erection machine, have the transverse movement action and the jacking action of the whole machine, are relatively complex, and a large number of driving parts are arranged, the front support leg control station 13 and the middle support leg control station 14 are respectively arranged on the front support leg of the bridge girder erection machine and the middle support leg of the bridge girder erection machine. The tail leg 15 and the bracket 16 have no excessive drive control except for hydraulic pressure; the control of the tail legs 15 and the carriages 16 is thus attributed to the master station control. The front supporting leg control station 13 and the middle supporting leg control station 14 are electrically connected with the main beam control station (including power supply and communication), and are used for controlling the complete machine transverse movement of the front supporting legs and the middle supporting legs and adopting a driving mode of frequency conversion and speed regulation. The front supporting leg control station 13 and the middle supporting leg control station 14 are respectively provided with 1 traversing stroke encoder 23 for detecting the actual displacement value of the front supporting leg and feeding back to the control platform. The transverse moving stroke encoder is an absolute value encoder.

The effect of the automatic control system for the frame girder in the embodiment is described below with respect to an engineering implementation case.

The road bridge girder erection machine usually adopts a tail feeding beam. When the bridge is fed with beams under the bridge, because the length of the precast beam pieces is greater than the clearance distance between the edges of the pier capping beams, the precast beam pieces need to be lifted in a longitudinal inclined mode, the capping beams are staggered, and the bridge deck can be provided with the precast beam pieces for installation. The inclination angle and the spatial position of the precast beam piece need to be strictly controlled in the hoisting process, so that the contact is prevented, and the difficulty and the safety risk are very high. The overall length of the Hangzhou overhead project is 34 kilometers, 9128T beams are counted in total in the upper structure, the whole line is overhead, municipal roads are arranged under bridges, and the roads are not interrupted in the construction process. Because the upper structure construction breakpoints are more, the bridge deck feeding beam cannot be adopted. By adopting the automatic control system for the beam erection of the embodiment, the construction is smoothly finished. As shown in fig. 3, the details are as follows:

1. bridge girder erection machine is in place

As shown in fig. 4, the bridge girder erection machine is in a girder erection state, and the girder transportation vehicle carries the precast beam pieces to a hanging beam position, and the parking position is right below the installation bridge span.

2. Beam body hoisting

As shown in fig. 5, the automatic beam erecting control system can lift the beam body in the air and withdraw the beam transporting vehicle. On the premise that the bent cap and the precast beam piece do not collide with each other, the collision is improved as much as possible. In this example, the precast beam pieces are set to be 300 mm from the bottom surface of the cap beam. The two vehicles synchronously move backwards to the front end of the beam to expose the cover beam, and the set distance is 300 mm.

3. Beam body lifting

As shown in fig. 6, the beam body is lifted by the automatic beam erecting control system at one end, the rotation angle is controlled not to exceed 15 degrees, namely, the lifting beam is stopped when the height difference between the front end and the rear end of the beam body is 7.3 meters.

4. Oblique horizontal movement of beam body

As shown in fig. 7, the automatic control system of girder erection starts the front and rear waling trusses, and moves the girder plates in parallel for about 3.7 m, and the lower end girder body moves out of the vertical projection range of the bent cap.

5. Beam-moving lift

As shown in fig. 8, the automatic control system of the beam erection starts the rear hoisting mechanism, and the beam plate can be moved backwards after the rear end is hoisted to exceed the support base cushion.

6. Beam drop in position

As shown in fig. 9, the T-beam moves backward, the automatic control system for erecting the beam starts the front and rear crown blocks, the whole beam body moves backward to the longitudinal target position, the automatic control system controls the traversing carriages of the front and middle support legs to traverse the whole bridge erecting machine to the transverse target position, after the precise alignment, the precast beam pieces fall into place, and the automatic beam erecting is finished.

The numbers in fig. 4 to 9 represent dimensions in millimeters.

The beam erecting process of the Hangzhou Yunzhou overhead project is installed in place at one time, no structures are touched midway, and finally the beam erecting process is accurate in place. In the aspect of installation efficiency, only 3-4T beams can be installed in one shift (calculated according to 12 hours) by completely adopting manual work; when the automatic beam erecting control system in the implementation is adopted to automatically erect the beams, 5-6T beams can be installed in one shift (calculated according to 12 hours), and the efficiency is improved by about 50%.

Through the technical scheme in this embodiment, can realize that the precast beam piece carries away to the automated control of the precast beam piece installation process of taking one's place after transporting the roof beam car, reduce personnel's consumption, improve installation effectiveness and once installation success rate.

Example 2

Safety protection is particularly important in the process of lifting the beam. In order to solve the safety protection problem in the construction process, the method is further optimized on the basis of the embodiment 1, and safety protection related measures are implemented by adopting a safety protection device. In this embodiment, the safety shield apparatus includes a tilt sensor 24, an anti-collision indicating device 25, a load sensor 26, and an RFID locating device. As shown in fig. 2, the following are specific:

the portable tilt sensor 24 is placed on the precast beam piece 31, and the position is not limited, and in this embodiment, the portable tilt sensor is placed on the upper surface of the precast beam piece 31 by way of example and in an absorption manner. The detection signal of the tilt sensor 24 is sent to the control system through a wireless transmission module of the tilt sensor. And when the longitudinal inclination angle change and the transverse inclination angle change of the precast beam piece 31 are detected to be larger than the early warning set value, stopping the automatic beam lifting process and giving an audible and visual alarm prompt.

The anti-collision indicating devices 25 are disposed at two ends of the precast beam piece 31, and the specific positions are not limited, and in this embodiment, the anti-collision indicating devices are disposed on top surfaces of left and right ends of the precast beam piece 31 in an absorption manner, which are front and rear anti-collision indicating devices, respectively. When the precast beam piece 31 is close to the bottom of the cover beam and reaches a set safety distance value, the machine is stopped and sound and light alarm is given. In this embodiment, the front and rear anti-collision indicating devices are portable ultrasonic anti-collision switches.

The front and rear crown blocks are respectively provided with 1 load sensor 26, and the specific position is not limited, but in the embodiment, the load sensors are installed on the front and rear crown blocks in a bolt connection manner. During the lifting process, the load sensor 26 detects that the load change rate is more than 10%, namely, the possibility of touch is indicated, the machine is stopped, and an audible and visual alarm is given.

In part of the time, a satellite communication interruption may occur due to a communication failure or the like, and the coordinate information of the precast beam piece 31 calculated using the RTK positioning technique may be distorted. In this embodiment, an RFID (radio frequency identification) positioning device is used for RTK dynamic positioning verification protection. The RFID location device includes an RFID position reader 27, a tag, a dolly encoder 28, and a dolly encoder 29. The RFID position reader 27 is mounted on the overhead traveling crane, and the mounting position and the mounting manner are not limited, but in this embodiment, the mounting manner by the bolt connection is selected and mounted on the overhead traveling crane body. The tag is arranged on a main beam of the bridge erecting machine, the installation position and the installation mode are not limited, and in the embodiment, for example, the tag is installed on the top surface of an upper chord of the main beam by means of epoxy glue adhesion. A transverse trolley encoder 28 and a longitudinal trolley encoder 29 are respectively arranged on a transverse trolley and a longitudinal trolley of the overhead travelling crane and are used for detecting the relative position change of the transverse trolley and the longitudinal trolley; the installation position and mode are not limited, and in this embodiment, the connection mode of the bolts is selected to be installed on the vehicle body of the traverse trolley and the longitudinal trolley. And when the difference value between the position change detected by the encoder and the RTK dynamic position change is larger than a set threshold value, stopping the machine and giving an acousto-optic alarm. In this embodiment, the dolly encoder 28 and the dolly encoder 29 use absolute value encoders, and the difference between the position change detected by the encoders and the RTK dynamic position change is set to a threshold value of not more than 10%.

In this embodiment, the tilt sensor, the ultrasonic anti-collision switch, and the load sensor all transmit detection signals to the control platform in a wireless communication manner. The acousto-optic alarm can be selected as the acousto-optic alarm and is arranged in a control station of the main beam, namely a driver's cabin at the tail part of the bridge erecting machine

Through the safety device of this embodiment, can avoid the slope of frame roof beam in-process precast beam piece, precast beam piece and bent cap striking, RTK positioning deviation too big, effectively improve the safety protection effect in the work progress, reduce the possibility that the incident takes place.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the scope of the embodiments of the present invention, and are intended to be covered by the claims and the specification.

Claims

1. An automatic gantry beam control system, comprising:

the RTK receiver (21) is arranged beside a winch of a crown block of the beam erecting equipment and used for positioning the spatial coordinates of the crown block;

the lifting height encoder (22) is arranged on a main shaft of a winch of a crown block of the beam erecting equipment and used for positioning a space coordinate of a lifting appliance;

the main beam control station is arranged in an operation chamber of the beam erecting equipment and is in communication connection with the RTK receiver (21) and the lifting height encoder (22); the main beam control station comprises a control platform, and the control platform is used for receiving the space coordinates of the crown block and the space coordinates of the lifting appliance; the crane control system is also used for automatically generating a beam erecting scheme according to the overhead travelling crane space coordinate, the lifting appliance space coordinate and the beam erecting control boundary condition and sending a beam erecting instruction;

the overhead traveling crane control station is arranged on a transverse moving trolley of an overhead traveling crane of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the lifting, transverse moving and longitudinal moving of the lifting appliance (17) according to the beam erecting instruction; and

and the support leg control station is arranged on the support leg of the beam erecting equipment, is electrically connected with the main beam control station and is used for controlling the complete machine transverse movement of the support leg according to the beam erecting instruction.

2. An automatic gantry control system according to claim 1, characterized in that: the beam erecting equipment is a bridge erecting machine, the crown block comprises a front crown block and a rear crown block, and the supporting legs comprise front supporting legs and middle supporting legs.

3. An automatic gantry control system according to claim 2, characterized in that: the number of the RTK receivers (21) is 2, and the RTK receivers are respectively arranged beside a winch of a front crown block and a rear crown block of the bridge girder erection machine.

4. An automatic gantry control system according to claim 2, characterized in that: the lifting height encoders (22) are 2 and are respectively arranged on the main shafts of the windlasses of the front and rear overhead cranes of the bridge girder erection machine.

5. An automatic gantry control system according to claim 2, characterized in that: the front supporting leg control station (13) and the middle supporting leg control station (14) are respectively provided with 1 traverse stroke encoder (23).

6. An automated gantry control system according to claim 1, further comprising a safety guard, the safety guard comprising:

an inclination sensor (24) placed on the precast beam piece (31);

the anti-collision indicating equipment (25) is arranged at two ends of the precast beam piece (31); and

and a load sensor (26) mounted on the crown block.

7. An automatic gantry control system according to claim 6, characterized in that: the anti-collision indicating equipment (25) is an ultrasonic anti-collision switch.

8. The automated gantry crane control system of claim 6, wherein the safety shield further comprises an RFID locating device, the RFID locating device comprising:

an RFID position reader (27) mounted on the overhead traveling crane;

the label is arranged on the main beam;

a trolley encoder (28) mounted on the trolley of the crown block, and

and the longitudinal moving trolley encoder (29) is arranged on the longitudinal moving trolley of the crown block.

9. An automatic gantry control system according to claim 8, wherein: and the main beam control station is provided with an audible and visual alarm.

10. An automatic gantry control system according to claim 1, 5 or 8, characterized in that: absolute value encoders are selected as the lifting height encoder (22), the transverse moving stroke encoder (23), the transverse moving trolley encoder (28) and the longitudinal moving trolley encoder (29).