Seven-axis hydraulic mechanical arm control system of heliostat cleaning vehicle and control method of seven-axis hydraulic mechanical arm control system

Abstract

The invention provides a seven-axis hydraulic mechanical arm control system of a heliostat cleaning vehicle and a control method of the seven-axis hydraulic mechanical arm control system, relates to the technical field of mechanical arm control, and solves the problems that the operation of manually controlling heliostat cleaning equipment of a heliostat field cleaning vehicle is complicated, a seven-axis mechanical arm control system is difficult to control a mechanical arm to clean heliostats, and the adaptability is poor. According to the technical scheme, a control system is a programmable logic controller and is connected with an encoder, a safety monitoring sensor and a hydraulic system through an IO module; the seven-axis hydraulic mechanical arm is formed by assembling a plurality of linear shafts and a rotating shaft, and the encoders comprise a pull rope encoder arranged on the linear shafts of the seven-axis hydraulic mechanical arm and a rotating encoder arranged on the rotating shaft of the seven-axis hydraulic mechanical arm; the working steps include safety detection, mechanical arm limiting safety detection, track teaching, heliostat cleaning, track reproduction and real-time safety monitoring. The automatic cleaning device can assist in automatic cleaning of the heliostat, closed-loop control is achieved, operation is fast and convenient, and dependence on manpower is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical arm control, in particular to a seven-axis hydraulic mechanical arm control system and a control method of a heliostat cleaning vehicle, which are suitable for controlling a hydraulic mechanical arm of a cleaning mechanism of a heliostat cleaning vehicle. Background Art

[0002] Tower solar thermal power plants have a certain installed capacity in Northwest my country. In tower solar thermal power plants, daily cleaning and maintenance of heliostats is a core issue. It is a more reasonable way to use a vehicle-mounted hydraulic manipulator for cleaning through manual control. The control of the vehicle-mounted manipulator is one of the core technologies of the heliostat cleaning vehicle. The current technical difficulties are as follows: Under the conditions of high day and night temperature difference and high dust in the Northwest, a hydraulic manipulator with strong environmental tolerance, closed-loop control function and multiple degrees of freedom is needed to help improve the automation of heliostat cleaning. The technology of hydraulic manipulator arms is very mature in China, and the operation control is carried out using a teaching pendant. However, for different application environments and requirements, the conventional hydraulic manipulator control action process is complicated and difficult, and the heliostat mirror is wide, and the cleaning brush has a large moving cleaning range, which requires precise moving position and appropriate force. The patent document with the announcement number CN110744587A discloses a control system for a seven-axis bionic robot arm, which uses seven groups of free joints, including a power motor, an encoder and a bracket. Its control system includes a human wearable device and a robot arm control device. Its disadvantages are: the control method is complicated, and the sensor controller needs to be triggered by human body movements to operate the mechanical arm to move. It only uses motor drive, which cannot achieve a large extension of the mechanical arm and extend the length of the mechanical arm, and it is difficult to monitor and limit the range of movement of the mechanical arm. The patent document with the announcement number CN105965503A discloses a hydraulic robot arm suitable for the tool changing operation of a shield machine, which uses multiple groups of mechanical arms and multiple groups of hydraulic cylinders to perform grasping actions. Its disadvantages are: few degrees of freedom, complex control method, inability to provide timely position feedback, and difficulty in quickly and accurately controlling the starting and end positions. The patent document with the announcement number CN113070877A discloses a variable posture mapping method for visual teaching of a seven-axis robot arm, which is used to control the action posture of the robot arm and imitate the action of the human body. Its disadvantages are: the control method is complicated and it is difficult to adapt to the action of the robot arm to automatically clean the heliostat. Therefore, the existing seven-axis robot arm is difficult to adapt to the cleaning of heliostats in solar thermal power plants, and the control system of the hydraulic manipulator dedicated to the heliostat cleaning vehicle in my country is still blank. Summary of the invention

[0003] The purpose of the present invention is to provide a seven-axis hydraulic mechanical arm control system and a control method for a heliostat cleaning vehicle, which solves the problems that the manual control of the heliostat cleaning equipment by the heliostat field cleaning vehicle is complicated to operate, the seven-axis mechanical arm control system is difficult to control the mechanical arm to clean the heliostat, and the adaptability is poor. The control system can assist the automatic cleaning of the heliostat, closed-loop control, quick and convenient operation, and greatly reduces the dependence on manual labor.

[0004] The technical solution adopted by the present invention is: the control system of the seven-axis hydraulic mechanical arm of the heliostat cleaning vehicle includes: a seven-axis hydraulic mechanical arm driven by a hydraulic system, and the seven-axis hydraulic mechanical arm is connected to a control system controlled by a teach pendant. The technical key points are: the control system is a programmable logic controller, and an encoder, a safety monitoring sensor and the hydraulic system are connected through an IO module; the seven-axis hydraulic mechanical arm is assembled by multiple linear axes and rotary axes, and the encoder includes a pull rope encoder arranged on the linear axis of the seven-axis hydraulic mechanical arm and a rotary encoder arranged on the rotary axis of the seven-axis hydraulic mechanical arm; the safety monitoring sensor includes: a limit switch for protecting the rotary axis, a hydraulic oil pressure sensor for monitoring the hydraulic oil pressure, a hydraulic oil level sensor for monitoring the hydraulic oil level and a hydraulic oil temperature sensor for monitoring the hydraulic oil temperature; the programmable logic controller is used to receive the status information of the encoder and the safety monitoring sensor collected by the IO module and transmit it to the teach pendant, receive the teaching command and operation command of the teach pendant, and use the hydraulic solenoid valve action of the hydraulic system to push the hydraulic mechanical arm to a predetermined position after obtaining the solenoid valve instruction through calculation.

[0005] The IO module includes: an analog input module, a digital input module and a digital output module; the analog input module is used to collect analog signals of the pull rope encoder, the rotary encoder and the hydraulic oil temperature sensor; the digital input module is used to collect digital input signals of the hydraulic oil pressure sensor and the limit switch; the digital output module is used to control the action of the hydraulic solenoid valve.

[0006] The multiple linear axes and rotating axes of the seven-axis hydraulic robotic arm are assembled from a first base rotating axis connected in sequence, a second linear axis for linear movement of the robotic arm in the up and down directions, a third rotating axis for up and down pitch rotation, a fourth linear axis for linear extension of the robotic arm, a fifth rotating axis for horizontal rotation, a sixth linear axis for linear extension of the arm span, and a seventh terminal rotating axis for driving the cleaning tool to rotate; the rotating axis is driven by a hydraulic motor, and the linear axis is driven by a hydraulic cylinder.

[0007] The control method of the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle includes the following working steps: S1. After the control system is started, the programmable logic controller detects the status of the IO module. If it is not working properly, an alarm will be issued; if it is working normally, the next step will be entered; S2, safety detection, the programmable logic controller detects through the IO module whether the limit switch of the safety monitoring sensor is collided, whether the hydraulic oil pressure switch is triggered, whether the hydraulic oil level sensor detects whether the level is within the safe range, whether the value of the hydraulic oil temperature sensor is within the safe range. When any of the detection items is triggered, the corresponding alarm information is displayed through the teaching pendant until the alarm is eliminated; when all items are detected to be safe, proceed to the next step; S3, mechanical arm limit safety detection, the programmable logic controller determines whether the position of the hydraulic mechanical arm linear axis and rotary axis is safe according to the values ​​transmitted by the pull rope encoder and rotary encoder obtained by the IO module. When the working position is unsafe, the corresponding alarm information is displayed through the teaching pendant, and the seven-axis hydraulic mechanical arm is manually operated to a safe position; when it is in a safe position, the next step is entered; S4, trajectory teaching, the specific process is: according to the shape of the heliostat, the teaching pendant is used to set the movement trajectory and program number formed by the seven-axis hydraulic manipulator passing through the starting point, multiple intermediate points and the end point on the heliostat to be cleaned, and then multiple movement trajectories and program numbers are set according to the above process and stored in the storage area of ​​the programmable logic controller; S5, cleaning the heliostats, the cleaning vehicle enters the heliostat field, drives to the working range of the heliostats and stops, controls the teach pendant to select the program number corresponding to the moving trajectory, reads the moving trajectory running program stored in the programmable logic controller, and the seven-axis hydraulic mechanical arm drives the cleaning brush to start cleaning. The seven-axis hydraulic mechanical arm automatically cleans the heliostats according to the set moving trajectory. After cleaning is completed, the cleaning vehicle drives to the edge of the next heliostat and stops, and repeatedly controls the teach pendant to reproduce the moving trajectory running program for cleaning. After all heliostats are cleaned, the seven-axis hydraulic mechanical arm automatically retracts to the origin for standby; S6, the trajectory is reproduced, and the seven-axis hydraulic mechanical arm mounted on the heliostat cleaning vehicle enters the mirror field. After entering the working range, the programmable logic controller automatically starts the program taught in step 4 to perform automatic cleaning work; S7. Real-time safety monitoring. During the cleaning process of the robotic arm, the programmable logic controller detects the following signals obtained through the IO module in real time: whether the limit switch is collided, whether the hydraulic oil pressure sensor is triggered, whether the hydraulic oil level sensor detects whether the level is within the safe range, and whether the hydraulic oil temperature sensor value is within the safe range. When any safety event of the detected signal is triggered, the seven-axis hydraulic robotic arm stops working until the fault is eliminated.

[0008] The advantages and positive effects of the present invention are as follows: since the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle adopts a seven-axis hydraulic mechanical arm, the control system adopts a programmable logic controller, and the encoder, safety monitoring sensor and hydraulic system are connected through the IO module, the seven-axis hydraulic mechanical arm can be effectively controlled. Among them, the pull rope encoder set on the linear axis of the mechanical arm and the rotary encoder set on the rotating axis are used as feedback units, which can timely and accurately feedback the position state of the mechanical arm, ensuring that the system has accurate control accuracy; the safety monitoring sensor can use the limit switch to protect the rotating axis, use the hydraulic oil pressure sensor to monitor the hydraulic oil pressure, use the hydraulic oil level sensor to monitor the hydraulic oil level, and use the hydraulic oil temperature sensor to monitor the hydraulic oil temperature, so as to form a closed-loop control, which can safely and accurately control the mechanical arm to perform cleaning actions; the ordinary programmable logic controller and the teaching pendant can be used to control the mechanical arm, which greatly reduces the cost of using a general robot system or a multi-axis machine tool controller, and also reduces the cost of a general robot teaching pendant. The cleaning method of the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle pre-sets the movement trajectory program of the mechanical arm on the heliostat surface according to different shapes and sizes of heliostats by using a programmed logic controller and a teaching pendant. The shapes of heliostats in the same heliostat field are basically the same. When cleaning, the pre-set movement trajectory program can be quickly and conveniently selected to automatically perform cleaning, which simplifies the complex control process of the existing general-purpose robot mechanical arm. At the same time, the safety and reliability of the automatic cleaning process can be guaranteed by the safety monitoring sensor. The automatic cleaning of the heliostat can be assisted, the closed-loop control is fast and convenient to operate, and the dependence on manual labor is greatly reduced, and the workload of the operator is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention is further described below in conjunction with the accompanying drawings.

[0010] Figure 1 It is a control connection principle diagram of the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle of the present invention; Figure 2 It is a schematic diagram of the overall structure of the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle of the present invention; Figure 3 It is a schematic diagram of the structure of a programmable logic controller and an IO module of the present invention; Figure 4 It is a structural schematic diagram of the hydraulic station of the present invention; Figure 5 It is a schematic diagram of the structure of the safety monitoring sensor of the present invention; Figure 6 A schematic diagram of a moving trajectory set on a heliostat according to the present invention; Figure 7 It is a schematic diagram of the operation interface of the teaching pendant screen of the present invention.

[0011] Explanation of the serial numbers in the figure: 1 programmable logic controller, 2 IO module, 3 teaching pendant, 4 encoder, 5 hydraulic system, 6 safety monitoring sensor, 21 analog input module, 22 digital input module, 23 digital output module, 41 pull rope encoder, 42 rotary encoder, 51 hydraulic station, 52 hydraulic solenoid valve, 53 first base rotating axis, 54 second linear axis, 55 third rotating axis, 56 fourth linear axis, 57 fifth rotating axis, 58 sixth linear axis, 59 seventh terminal rotating axis, 61 limit switch, 62 hydraulic oil pressure sensor, 63 hydraulic oil level sensor, 64 hydraulic oil temperature sensor, 70 heliostat, 71 moving trajectory. DETAILED DESCRIPTION

[0012] according to Figure 1-7 The specific scheme of the present invention is described in detail, as shown in Example 1. Figure 1 and Figure 2 As shown, the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle is mainly composed of a programmable logic controller 1 as a control system, an IO module 2, a teach pendant 3, an encoder 4, a hydraulic system 5 and a safety monitoring sensor 6. The seven-axis hydraulic mechanical arm is driven by the hydraulic system 5, and the seven-axis hydraulic mechanical arm is controlled by the teach pendant 3 and the programmable logic controller 1.

[0013] The programmable logic controller 1 is connected to the IO module 2 and the teach pendant 3. The programmable logic controller 1 receives status information from the encoder 4 through the IO module; transmits status information of the encoder 4 and the safety monitoring sensor 6 to the teach pendant 3 through Ethernet; receives teaching commands and operation commands sent by the teach pendant 3 to the programmable logic controller 1 through Ethernet; calculates the robot arm action instructions, i.e., the solenoid valve instructions, based on the status information collected by the IO module 2 and the operation commands issued by the teach pendant 3, controls the hydraulic system 5 through the IO module 2, and drives the robot arm to move to a predetermined position; and monitors the status of the safety monitoring sensor 6 throughout the operation process through the IO module 2. Once the safety monitoring sensor 6 sends an unsafe signal, the system immediately stops running and displays an alarm message on the teach pendant 3.

[0014] like Figure 2 and Figure 3As shown, the IO module 2 includes: an analog input module 21, a digital output module 23 and a digital input module 22. The IO module 2 is connected to the encoder 4, the safety monitoring sensor 6 and the hydraulic system 5. The analog input module 21 is used to collect analog signals from the encoder 4 and the safety monitoring sensor 6 and transmit the status information to the programmable logic controller 1; the digital input module 22 is used to collect digital signals from various sensors and other devices of the safety monitoring sensor and transmit the status information to the programmable logic controller; the digital output module 23 is used to receive the mechanical arm motion instructions of the programmable logic controller 1 and transmit them to the hydraulic system. Commercially available IO modules can be used, for example, the analog input module model is XD-E8AD-A8, all of which are 4-20mA current input interfaces; the digital input module 22, model is XD-E32PX-E, 32-way PNP digital input interface; the digital output module 23, model is XD-E32PX-C, 32-way 24V digital output interface.

[0015] The teaching pendant 3 is used for manually controlling the robot arm and teaching the program. A commercially available handheld teaching pendant can be used, such as the wireless handheld touch screen of the Xinjie brand, model MTG765-UT, and the operation control system is written using the Xinjie touchwin software. The protection level is IP67 and the screen size is 7 inches.

[0016] The encoder 4 includes four draw-wire encoders 41 and three rotary encoders 42. The draw-wire encoders are respectively arranged on the linear axes of the seven-axis hydraulic manipulator to feedback the current positions of the linear axes; the rotary encoders 42 are respectively arranged on the rotating axes of the seven-axis hydraulic manipulator to feedback the current angles of the rotating axes. The draw-wire encoders and the rotary encoders transmit the acquired state information to the analog input module 21. Commercially available encoders can be used, for example: Elco brand rotary encoders, model ELCO-KDM1000A-A6PR.KS, output signal form 4-20mA analog; model ADK-1020151212MA, output signal form 4-20mA analog.

[0017] like Figure 4 As shown, the hydraulic system 5 includes: a hydraulic station 51 for providing power, a hydraulic cylinder for driving the linear axis of the robot arm, a hydraulic motor for driving the rotary axis of the robot arm, and a hydraulic solenoid valve group composed of multiple hydraulic solenoid valves 52 for controlling the movement of the hydraulic cylinder and the hydraulic motor. The hydraulic solenoid valve receives the solenoid valve command action sent by the programmable logic controller through the digital output module 23.

[0018] like Figure 2 and Figure 5As shown, the safety monitoring sensor 6 includes a limit switch 61, a hydraulic oil pressure sensor 62, a hydraulic oil level sensor 63 and a hydraulic oil temperature sensor 64 arranged on the hydraulic station. The limit switch 61 is used to protect the rotating shaft of the mechanical arm, the hydraulic oil pressure sensor 62 is used to monitor the hydraulic oil pressure, the hydraulic oil level sensor 63 is used to monitor the hydraulic oil level, and the hydraulic oil temperature sensor 64 is used to monitor the hydraulic oil temperature. The monitoring status obtained by each sensor is transmitted to the programmable logic controller through the digital input module 22. Commercially available safety monitoring sensors can be used, such as the Omron brand model WLCA12-TH limit switch, which uses a normally closed contact and a switch signal; the hydraulic oil pressure sensor uses the Shinco brand hydraulic oil pressure switch 62, model JCS-02H, working pressure 0-35MP, switch signal; the hydraulic oil level sensor 63 uses a ball float switch, a single ball diameter of 220mm, a switch signal; the hydraulic oil temperature sensor 64, model ZQ-WA-XS, 4-20mA analog output.

[0019] like Figure 2As shown, the seven-axis hydraulic manipulator adopts multiple linear axes and rotation axes connected to each other. This embodiment is composed of a first base rotation axis 53, a second linear axis 54 for linear movement of the manipulator in the up and down directions, a third rotation axis 55 for pitching and rotating up and down, a fourth linear axis 56 for linear extension of the manipulator, a fifth rotation axis 57 for horizontal rotation, a sixth linear axis 58 for linear extension of the arm span, and a seventh terminal rotation axis 59 for driving the cleaning tool to rotate. The rotation axis is driven by a hydraulic motor, and the linear axis is driven by a hydraulic cylinder. Among them, the first base rotating axis 53 is the rotating axis of the base of the whole robot arm. The driving device adopts a hydraulic motor to drive the whole robot arm to rotate. The rotation angle is fed back by a rotary encoder 42, and a limit switch 61 is used for safety protection; the second linear axis 54 is connected to the top of the first base rotating axis, and a hydraulic cylinder is used to drive the whole robot arm to move up and down. The rising and falling distance is fed back by a pull rope encoder 41; the third rotating axis 55 is connected to the second linear axis, and a hydraulic motor is used to drive the fourth linear axis 56 to pitch up and down. The rotation angle is fed back by a rotary encoder 42, and a limit switch 62 is used for safety protection; the fourth linear axis 56 is connected to the third rotating axis 55, and a hydraulic cylinder is used to drive the rear section of the robot arm to move linearly The fifth rotating shaft 57 is connected to the fourth linear shaft, and a hydraulic motor is used to drive the rear section of the mechanical arm to rotate horizontally. The rotation angle is fed back by a rotary encoder 42, and a limit switch 61 is used for safety protection. The sixth linear shaft 58 is connected to the fifth rotating shaft 57, and a hydraulic cylinder is used to drive the seventh terminal rotating shaft 59 to perform linear motion. The telescopic distance is fed back by a rope encoder 41. The sixth linear shaft 58 is for further extending the arm span in the linear direction of the mechanical arm. The seventh terminal rotating shaft 59 is connected to the end of the sixth linear shaft 58, and a hydraulic motor is used to drive the cleaning tool to rotate. The rotation angle is fed back by a rotary encoder 42, and a limit switch is used for safety protection. The corresponding hydraulic system can adopt a commercially available hydraulic station with a working pressure of 25MP and a flow rate of 300L / min; there are four hydraulic cylinders with strokes of 2000mm, 1600mm, 800mm, and 1500mm respectively; there are three hydraulic motors with displacements of 150L / min, 100L / min, and 50L / min respectively, and the hydraulic solenoid valve group contains seven hydraulic solenoid valves 52; the hydraulic motor can be used as a rotating axis and the hydraulic cylinder can be used as a linear axis to form a seven-axis hydraulic robotic arm.

[0020] The programmable logic controller uses commercially available PLC devices as the core processor of the control system, such as the XD5E-30T4 series PLC of the Xinjie brand, which supports Ethernet program transmission, basic processing instructions of 0.01 to 0.03us, scanning time of 10,000 steps of 1ms, program capacity of 1.5MB, program code is written using the Xinjie brand XDPPro, and the programming language uses the STL instruction statement table. Figure 1 As shown, the programmable logic controller 1 is provided with a position and angle feedback processing program module for receiving the status information of the encoder position data and the hydraulic oil temperature data transmitted by the analog input module 21 of the IO module 2; the programmable logic controller 1 is provided with a safety monitoring program module for receiving the status information of the limit, liquid level and pressure signal of the safety monitoring sensor transmitted by the digital input module 22; the programmable logic controller 1 sends the received encoder position data status information to the teach pendant 3, and when the status information of the hydraulic oil temperature data, limit, liquid level and pressure signal generates an alarm signal, it sends it to the teach pendant 3, the teach pendant displays the information through the status monitoring interface, the teach pendant 3 sends an action instruction to the programmable controller 1 through the operation interface, and the motion instruction is made by the position and angle feedback processing program module and the position control algorithm, and finally the hydraulic mechanical arm action instruction is issued, which is converted into a hydraulic solenoid valve action instruction through the digital output module 23 and sent to the hydraulic battery valve of the hydraulic system to control the hydraulic solenoid valve 52 to act, and the hydraulic solenoid valve controls the hydraulic cylinder and the hydraulic motor to act, and finally the hydraulic mechanical arm is pushed to the predetermined position.

[0021] Embodiment 2. The present invention also provides a control method for the seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle. The embodiment is a working process in which the heliostat cleaning vehicle is set with the seven-axis hydraulic mechanical arm control system to clean a heliostat with an area of ​​30 square meters. The heliostat has a rectangular mirror surface of 6 meters in length and 5 meters in width. Specifically, the method comprises the following steps: S1. After the control system is powered on, the hydraulic station of the hydraulic system is started, and the programmable logic controller starts to maintain the status of each functional module, and detects whether the analog input module 21, the digital output module 23 and the digital input module 22 in the IO module are working normally. If they are not working properly, the programmable logic controller will issue an alarm indication; if they are working normally, the next working step will be entered; S2, safety detection, the programmable logic controller 1 starts to maintain system safety, firstly, it detects whether the limit switch 61 of the safety monitoring sensor 6 is collided, whether the hydraulic oil pressure sensor 62 switch is triggered, the hydraulic oil level sensor 63 detects whether the level is within the safety range, and whether the value of the hydraulic oil temperature sensor 64 is within the safety range through the IO module 2. When any of the detection items is triggered, the corresponding alarm information is displayed through the teaching pendant, and the hydraulic mechanical arm cannot make any action until the alarm is eliminated; when all items are detected to be safe, it proceeds to the next step; S3, mechanical arm limit safety detection, the programmable logic controller 1 determines whether the position of the hydraulic mechanical arm linear axis and the rotary axis is safe according to the values ​​transmitted by the pull rope encoder 41 and the rotary encoder 42 obtained by the IO module 2. When the working position is unsafe, the corresponding alarm information is displayed through the teaching pendant, and a prompt is given to manually operate the seven-axis hydraulic mechanical arm to a safe position; when it is in a safe position, the next working step is entered; S4, trajectory teaching, the specific process is: according to the shape of the heliostat surface, the seven-axis hydraulic mechanical arm is set through the teaching device 3 to form a moving trajectory 71 and a program number formed by sequentially passing through the starting point, multiple intermediate points and the end point on the heliostat 70 to be cleaned, and then a variety of moving trajectories and program numbers are set according to the above process and stored in the storage area of ​​the programmable logic controller; Figure 6 As shown, a square wave curve moving track 71 is set on the surface of the rectangular heliostat, such as Figure 7 As shown, in the operation interface of the teach pendant screen, input 1 for the program number item, that is, set the program number 1, input 1 for the program point number item, operate the seven-axis hydraulic manipulator through the teach pendant 3, move the cleaning brush fixed on the seventh end rotation axis of the seven-axis hydraulic manipulator to the position of point 1 in the upper right corner of the heliostat, click the "point teaching confirmation" button on the teach pendant to confirm, and point 1 is set successfully; the program number remains unchanged, input 2 for the program point number, operate the manipulator through the teach pendant 3, move the cleaning brush fixed on the seventh end rotation axis of the manipulator to point 2 in the lower right corner, click the "point teaching confirmation" button on the teach pendant to confirm, and point 2 is set successfully; then repeat this process, and then set and teach all 18 points according to the square wave curve movement trajectory, and the movement trajectory teaching of program 1 is completed; you can also set multiple movement trajectories for program numbering to complete trajectory teaching; S5, cleaning the heliostats. The cleaning vehicle enters the heliostat field, drives to the working range of the heliostats and stops. The teach pendant is controlled to select the program number corresponding to the moving trajectory, and the moving trajectory running program stored in the programmable logic controller is read. The seven-axis hydraulic mechanical arm drives the cleaning brush to start cleaning. The seven-axis hydraulic mechanical arm automatically cleans the heliostats according to the set moving trajectory. After cleaning, the cleaning vehicle drives to the edge of the next heliostat and stops. The teach pendant is repeatedly controlled to reproduce the moving trajectory running program for cleaning. After all the heliostats are cleaned, the seven-axis hydraulic mechanical arm automatically retracts to the origin for standby. S6, the trajectory reappears, the hydraulic manipulator loaded on the heliostat cleaning vehicle enters the mirror field, after entering the working range, the programmable logic controller 1 automatically starts the program taught in step 4 for automatic cleaning; S7. Real-time safety monitoring. During the cleaning process of the robotic arm, the programmable logic controller detects the following signals obtained through the IO module in real time: whether the limit switch is collided, whether the hydraulic oil pressure sensor is triggered, whether the hydraulic oil level sensor detects whether the level is within the safe range, and whether the hydraulic oil temperature sensor value is within the safe range. When any safety event of the detected signal is triggered, the robotic arm stops working until the fault is eliminated.

[0022] Complete the control process of the seven-axis hydraulic robot arm control system.

[0023] The control system of the present invention adopts the Xinjie XD5 series PLC as the computing core and the Xinjie handheld touch screen as the teaching pendant, realizing the closed-loop control and teaching functions of the seven-axis hydraulic manipulator at a very low cost, which provides great help for the automated cleaning of heliostats, especially the automated cleaning of special-shaped heliostats.

[0024] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

[0025] In summary, the purpose of the present invention is achieved.

Claims

1. A seven-axis hydraulic mechanical arm control system for a heliostat cleaning vehicle, comprising: The seven-axis hydraulic mechanical arm is driven by a hydraulic system, and the seven-axis hydraulic mechanical arm is connected to a control system controlled by a teach pendant, and is characterized in that: the control system is a programmable logic controller, and an encoder, a safety monitoring sensor and the hydraulic system are connected through an IO module; the seven-axis hydraulic mechanical arm is assembled from multiple linear axes and rotary axes, and the encoder includes a pull-rope encoder arranged on the linear axis of the seven-axis hydraulic mechanical arm and a rotary encoder arranged on the rotary axis of the seven-axis hydraulic mechanical arm; the safety monitoring sensor includes: a limit switch for protecting the rotary axis, a hydraulic oil pressure sensor for monitoring the hydraulic oil pressure, a hydraulic oil level sensor for monitoring the hydraulic oil level and a hydraulic oil temperature sensor for monitoring the hydraulic oil temperature; the programmable logic controller is used to receive the status information of the encoder and the safety monitoring sensor collected through the IO module and transmit it to the teach pendant, receive the teaching command and operation command of the teach pendant, and use the hydraulic solenoid valve action of the hydraulic system to push the hydraulic mechanical arm to a predetermined position after obtaining the solenoid valve instruction through calculation.

2. The seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle according to claim 1 is characterized in that: The IO module includes: an analog input module, a digital input module and a digital output module; the analog input module is used to collect analog signals of the pull rope encoder, the rotary encoder and the hydraulic oil temperature sensor; the digital input module is used to collect digital input signals of the hydraulic oil pressure sensor and the limit switch; the digital output module is used to control the action of the hydraulic solenoid valve.

3. The seven-axis hydraulic mechanical arm control system of the heliostat cleaning vehicle according to claim 1 is characterized in that: The multiple linear axes and rotating axes of the seven-axis hydraulic robotic arm are assembled from a first base rotating axis connected in sequence, a second linear axis for linear movement of the robotic arm in the up and down directions, a third rotating axis for up and down pitch rotation, a fourth linear axis for linear extension of the robotic arm, a fifth rotating axis for horizontal rotation, a sixth linear axis for linear extension of the arm span, and a seventh terminal rotating axis for driving the cleaning tool to rotate; the rotating axis is driven by a hydraulic motor, and the linear axis is driven by a hydraulic cylinder.

4. A control method for a seven-axis hydraulic mechanical arm control system of a heliostat cleaning vehicle, comprising the following working steps: S1. After the control system is started, the programmable logic controller detects the status of the IO module. If it is not working properly, an alarm will be issued; if it is working normally, the next step will be entered; S2, safety detection, the programmable logic controller detects through the IO module whether the limit switch of the safety monitoring sensor is collided, whether the hydraulic oil pressure switch is triggered, whether the hydraulic oil level sensor detects whether the level is within the safe range, whether the value of the hydraulic oil temperature sensor is within the safe range. When any of the detection items is triggered, the corresponding alarm information is displayed through the teaching pendant until the alarm is eliminated; when all items are detected to be safe, proceed to the next step; S3, mechanical arm limit safety detection, the programmable logic controller determines whether the position of the hydraulic mechanical arm linear axis and rotary axis is safe according to the values ​​transmitted by the pull rope encoder and rotary encoder obtained by the IO module. When the working position is unsafe, the corresponding alarm information is displayed through the teaching pendant, and the seven-axis hydraulic mechanical arm is manually operated to a safe position; when it is in a safe position, the next step is entered; S4, trajectory teaching, the specific process is: according to the shape of the heliostat, the teaching pendant is used to set the movement trajectory and program number formed by the seven-axis hydraulic manipulator passing through the starting point, multiple intermediate points and the end point on the heliostat to be cleaned, and then multiple movement trajectories and program numbers are set according to the above process and stored in the storage area of ​​the programmable logic controller; S5, cleaning the heliostats, the cleaning vehicle enters the heliostat field, drives to the working range of the heliostats and stops, controls the teach pendant to select the program number corresponding to the moving trajectory, reads the moving trajectory running program stored in the programmable logic controller, and the seven-axis hydraulic mechanical arm drives the cleaning brush to start cleaning. The seven-axis hydraulic mechanical arm automatically cleans the heliostats according to the set moving trajectory. After cleaning is completed, the cleaning vehicle drives to the edge of the next heliostat and stops, and repeatedly controls the teach pendant to reproduce the moving trajectory running program for cleaning. After all heliostats are cleaned, the seven-axis hydraulic mechanical arm automatically retracts to the origin for standby; S6, the trajectory is reproduced, and the seven-axis hydraulic mechanical arm mounted on the heliostat cleaning vehicle enters the mirror field. After entering the working range, the programmable logic controller automatically starts the program taught in step 4 to perform automatic cleaning work; S7, real-time safety monitoring. During the cleaning process of the robotic arm, the programmable logic controller detects the following signals obtained through the IO module in real time: whether the limit switch is collided, whether the hydraulic oil pressure switch is triggered, whether the hydraulic oil level sensor detects whether the level is within the safe range, and whether the hydraulic oil temperature sensor value is within the safe range. When any safety event of the detected signal is triggered, the seven-axis hydraulic system stops working until the fault is eliminated.

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