An electrical control system for a robot used in a tunnel boring machine

Abstract

The present invention relates to an electrical control system for a robot for a tunnel boring machine, comprising a main control system, a motion control system, an operating unit for controlling the robot's movements, and a sensor group for detecting the state parameters of each degree of freedom of the robot; the motion control system comprises joint drive mechanisms for each degree of freedom of the robot; the main control system comprises an input unit for collecting data of each sensor in the sensor group, an output unit for outputting control instructions to the joint drive mechanism, and a communication unit; the input unit and the output unit are connected to each sensor through a communication unit to collect the state parameters of each degree of freedom, and are also connected to each joint drive mechanism through a communication unit to realize the control of each joint movement. The present invention realizes a robot electrical control system with high positioning accuracy, strong anti-interference ability, strong real-time performance, and easy wiring at a complex tunnel boring machine construction site.

Description

Technical Field

[0001] The invention relates to an electrical control system of a robot for a tunnel boring machine, belongs to the field of multi-degree-of-freedom robot control, and in particular to a control system of a mechanical arm used in tunnel construction. Background Art

[0002] The full-section tunnel boring machine integrates excavation, support and slag discharge functions. Due to its high efficiency, high safety and environmental friendliness, it is widely used in underground projects such as urban subways, cross-river and cross-sea tunnels in my country.

[0003] During the construction process of a tunnel boring machine, the working conditions are complex and the environment is harsh. In order to improve the degree of automation and intelligence and reduce the safety risks of construction workers, more and more people are considering using robots to perform some related auxiliary work, such as cleaning slag and flushing and inspecting cutters.

[0004] Take the inspection and replacement of tools as an example. During the construction of a full-section tunnel boring machine, the consumption of tools is large and the replacement is frequent. The inspection and replacement time of tools accounts for more than 10% of the tunnel construction cycle. At present, the actual construction process mainly relies on manual operation for tool replacement. There are great safety hazards in the construction environment such as deep burial and high water pressure. Operators often need to change tools under pressure. Long-term work will cause irreversible damage to the human body and even pose a risk of major safety accidents such as casualties. How to reduce the risks brought by manual tool change, improve construction efficiency, reduce construction costs, and achieve a breakthrough in "machines replacing people" is a difficult problem that needs to be solved in the industry. Therefore, it is imperative to develop a tool change robot that can replace manual tool change.

[0005] When the tool-changing robot is changing tools, even a small deviation will cause the robot's end effector to be unable to enter the hob cutter seat. Large deviations may even cause a collision with the machine, resulting in destructive consequences. When the robot is changing tools, personnel cannot enter the tool cabin to check the situation, and there are many twisted legs and stirring rods between the cutter disc and the main drive, making it impossible to monitor the tool changing process by arranging cameras. Therefore, in order to achieve automatic and accurate tool changing, the tool-changing robot must have high positioning accuracy, strong anti-interference ability, strong real-time performance, and precise visual guidance, so as to complete efficient and fast tool changing operations under complex working conditions.

[0006] Therefore, due to the narrow environment, many structural components and harsh environment of the tunnel boring machine construction site, it can be seen from the tool changing operation application scenario that the tunnel boring machine robot has many degrees of control freedom and needs to be equipped with a visual system, etc. The connecting wiring harness is complex and the related control system design is difficult.

[0007] The Chinese invention patent application with patent publication number CN114087240A discloses a hydraulic control system for a tool changing robot for a tunnel boring machine. This solution only involves the hydraulic system of the tool changing robot and does not involve the electrical control system architecture and design solution.

[0008] The published text of the Chinese invention patent application with patent publication number CN112392499A discloses an electrical control system for a rock drilling robot and a rock drilling robot, wherein the electrical control system design adopts a wireless AP module for data transmission. Wireless communication is difficult to achieve long-distance transmission, and it is difficult to ensure stable and reliable data transmission in the harsh environment of strong electromagnetic interference during tunnel boring machine construction.

[0009] The published text of the Chinese invention patent application with patent number CN114183179A discloses an automatic control system for an anchor trolley and an anchor trolley. The scheme uses an ordinary proportional valve to realize the control of the robotic arm, and the upper computer performs PID calculations for the position loop and speed loop. The algorithm processing is difficult, and the use of ordinary solenoid valves requires a large number of modules such as relays and amplifiers, which can easily cause the system wiring harness to be complex and have many fault points. The corresponding control system design is not suitable for use in the tool changing scenario of a tunnel boring machine with a complex structure and a small space.

[0010] The Chinese utility model patent authorization publication with patent publication number CN211857280U discloses an electrical control system for an anchor trolley based on CAN bus communication. In this solution, only the input module and the data display module are connected to the controller through the CAN bus. The bus technology is not used for the control of the actuator, and the problem of too many wiring harnesses cannot be avoided, resulting in complex system wiring and a high failure rate. Summary of the invention

[0011] The purpose of the present invention is to provide an electrical control system for a robot for a tunnel boring machine, so as to solve the problem that the robot control system in the prior art is difficult to be applied to the construction scene of the tunnel boring machine.

[0012] To achieve the above object, the solution of the present invention includes:

[0013] The technical solution of the electrical control system of a robot for a roadheader of the present invention comprises a main control system, a motion control system, an operating unit for controlling the action of the robot and a sensor group for detecting the state parameters of each degree of freedom of the robot; the motion control system comprises a joint driving mechanism of each degree of freedom of the robot;

[0014] The main control system includes an input unit for collecting data from each sensor in the sensor group, an output unit for outputting control instructions to the joint drive mechanism, and a communication unit; the input unit and the output unit are connected to each sensor through the communication unit to collect state parameters of each degree of freedom, and are also connected to each joint drive mechanism through the communication unit to realize the control of each joint action.

[0015] The present invention proposes an electrical control system architecture for a robot for a tunnel boring machine, which can be applied to the electrical control system of a tool changing robot for changing tools, for example. In the scheme of the present invention, the input of sensor acquisition signals and the output of joint control signals are centralized through a communication network in a communication unit, which can effectively simplify the signal transmission line. It can meet the complex working conditions of tunnel boring machine construction and the operational requirements of efficient and safe construction.

[0016] Furthermore, the communication unit includes a CAN communication network, and the input unit, the output unit, each joint driving mechanism and each sensor are connected to the CAN communication network, and data is exchanged through the CAN communication network.

[0017] The CAN bus technology is used to collect sensor signals and transmit joint control signals. The technology is mature and reliable with strong anti-interference ability.

[0018] Furthermore, the CAN communication network includes several axis motion control cards whose communication ends are cascaded in sequence, each axis motion control card corresponds one-to-one to each degree of freedom of the robot, each axis motion control card controls a joint drive mechanism connected to the corresponding degree of freedom, and a sensor corresponding to each degree of freedom is connected to the axis motion control card corresponding to the degree of freedom to enable the axis motion control card to sample the corresponding sensor.

[0019] The present invention sequentially cascades the components of the CAN bus network through the axis motion control card. The axis card, as a communication site, also collects relevant data of the joints and degrees of freedom. The central processing unit identifies which communication site different data information comes from, thereby identifying the relevant information of the corresponding active part.

[0020] Furthermore, the axis motion control card collects state parameters of the corresponding degree of freedom, and compares them with the command signal of the joint drive mechanism corresponding to the degree of freedom, so as to realize closed-loop control of the joint drive mechanism of the degree of freedom.

[0021] The present invention utilizes a CAN bus proportional servo valve with an axis card to form a CAN communication network, collects control commands, joint and degree of freedom related data on the axis card, and performs closed-loop control of joint control on-site on the axis card, thereby improving robot control accuracy and response speed and reducing wiring harnesses.

[0022] Furthermore, the sensor includes a hydraulic pressure sensor corresponding to the joint drive mechanism and a motion detection unit corresponding to the degree of freedom, and the state parameter includes the hydraulic pressure of the joint drive mechanism corresponding to the degree of freedom and the motion amount of the corresponding degree of freedom.

[0023] Furthermore, the joint drive mechanism includes a proportional valve for adjusting the corresponding hydraulic pressure; the axis motion control card is connected to the proportional valve of the corresponding joint drive mechanism, and controls the movement of the corresponding degree of freedom by adjusting the opening of the proportional valve, and stops the movement of the joint of the corresponding degree of freedom after the movement of the corresponding degree of freedom reaches the target value.

[0024] Furthermore, the axis motion control card collects the hydraulic pressure of the joint drive mechanism corresponding to the degree of freedom, and stops the movement of the joint of the degree of freedom after the pressure reaches a set value.

[0025] The pressure information is fed back to the main control system, which compares the pressure information with the set upper pressure limit, and issues a protection command to the motion control system when the pressure information is greater than the upper pressure limit. The motion control system controls the corresponding hydraulic drive to stop moving according to the protection command. When the movement of the hydraulic drive is hindered (such as a failure of the hydraulic drive or encountering other obstacles), if hydraulic oil continues to be injected into the hydraulic drive, the pressure of the hydraulic drive will continue to increase. Therefore, the pressure information of the hydraulic drive is fed back to the main control system through the pressure detection unit, so that the main control system can judge the working state of the hydraulic drive through the pressure information, and issue a protection command when the pressure exceeds the set upper pressure limit to stop injecting hydraulic oil into the hydraulic drive, thereby avoiding damage to the hydraulic drive.

[0026] Further, it also includes a robot monitoring system and a visual recognition system;

[0027] The robot monitoring system includes a plurality of monitoring units and monitoring lighting sources; the monitoring unit includes a forward monitoring camera for obtaining the robot's end position and forward field of view and a backward monitoring camera for obtaining the robot's backward field of view; the monitoring lighting source is used to illuminate the robot's surroundings;

[0028] The visual recognition system includes a visual recognition unit, a visual lighting source, a water spray device and an air jet device; the visual recognition unit is installed at the end of the robot, and is used to collect images through an industrial camera and perform image recognition on the collected images. The visual lighting source is set at the end of the robot, and is used to provide fill light when the industrial camera collects images; the water spray device and the air jet device are set toward the lens of the industrial camera, and are used to spray water to remove sludge on the lens and spray air to remove water droplets on the lens.

[0029] A visual recognition system with a self-cleaning function is also provided to achieve visual guidance of the robot, thereby enabling, for example, the tool changing robot to complete automated operations of automatic tool changing.

[0030] Further, the operating unit includes a human-machine interaction system arranged in the main control room of the tunnel boring machine, and a local control system arranged at the robot control cabinet;

[0031] The human-machine interaction system is connected to the main control system and displays sensor information and real-time images collected by the monitoring unit, and controls the robot according to the interaction;

[0032] The local control system includes a control button component and an indicator light component. The control button component is used to realize local operation control of the robot; the indicator light component is used to indicate the working status of the robot power supply and the working status of each joint driving mechanism.

[0033] In addition to being able to control the robot in the main control room of the tunnel boring machine, the present invention can also perform some on-site controls in the robot control cabinet and indicate the working status of the power supply and the valve group on-site.

[0034] Furthermore, it also includes a protection system, which includes a circuit breaker and an emergency stop switch; after detecting that the current exceeds a set threshold or leakage occurs, the power supply is disconnected by the circuit breaker to achieve protection; the emergency stop switch is used to control the motion control system to stop working when it is pressed, and each degree of freedom no longer moves.

[0035] When the present invention detects that the current of the robot control system is too high or there is leakage, it can actively disconnect the power supply to achieve protection, avoiding the risk of damaging electrical components and threatening personal safety. When an emergency occurs during the operation of the robot, pressing the emergency stop switch can stop the motion control system from working, and all hydraulic drive parts will no longer drive the mechanical device to continue to move, so as to ensure the personal safety of the staff and further reduce safety hazards; after the fault is eliminated, the emergency stop switch is reset and the entire system returns to normal. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 2. It is a schematic diagram of the structure of the tool changing robot for a tunnel boring machine in an embodiment;

[0037] Figure 2 2. It is a schematic diagram of the control system framework of the tool changing robot for the tunnel boring machine in the embodiment;

[0038] Figure 3 It is a CAN communication network formed by cascading the proportional servo valves with the axis motion control cards in the embodiment through the CAN bus.

[0039] In the figure: 11, servo motor; 12, main arm action actuator; 121, main arm telescopic cylinder; 122, main arm rotation cylinder; 123, main arm swing cylinder; 13, auxiliary arm action actuator; 131, auxiliary arm telescopic cylinder; 132, auxiliary arm rotation cylinder; 133, auxiliary arm swing cylinder; 14, end action actuator; 141, end rotation cylinder; 151, upper clamping jaw cylinder; 152, lower clamping jaw cylinder; 161, left hydraulic motor; 162, right hydraulic motor; 201, protection system; 202, power supply system; 203, human-computer interaction system; 204, main control system; 205, local control system; 206, motion control system; 207, tool changing robot mechanism; 208, sensor group; 209, monitoring system; 210, visual recognition system. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0041] The purpose of the present invention is to provide a stable and efficient robot electrical control system during the complex full-face tunnel boring machine construction operation, which is suitable for the mature application of mechanical arms and robots on tunnel boring machines.

[0042] In this embodiment, the application scenario of the tunnel boring machine tool changing robot is taken as an example to introduce the electrical control system of the tunnel boring machine robot of the present invention. The tunnel boring machine tool changing robot in this embodiment can realize the automatic replacement of the shield machine cutterhead tool, realize the machine to replace the human work, reduce the labor intensity of the operators, improve the efficiency of tunnel construction, and at the same time ensure the personal safety of the construction operators.

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings of the specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The tool changing robot for the full-face tunnel boring machine in this embodiment is as follows Figure 1 As shown, it includes a robot ground rail, a track platform, a main arm arranged on the track platform, a secondary arm connected to the main arm, and a robot arm end. The tool changing robot is arranged on the ground rail through the track platform, and the track platform can move forward and backward on the ground rail to increase the robot's axial moving distance of the cutter head, so that the robot can be retracted into the robot warehouse when not working to prevent damage. The forward and backward movement of the robot's track platform along the ground rail direction is driven by a servo motor 11 arranged on the track platform.

[0045] A main arm motion actuator 12 for moving the robot's main arm is arranged on the rail platform. The main arm motion actuator 12 includes a main arm telescopic cylinder 121 for telescoping forward and backward, a main arm rotating cylinder 122 arranged at the action end of the main arm telescopic cylinder 121 for rotating left and right, and a main arm swinging cylinder 123 arranged at the action end of the main arm rotating cylinder 122 for swinging the main arm up and down.

[0046] The main arm swing cylinder 123 has an auxiliary arm motion actuator 13 for moving the auxiliary arm, which includes an auxiliary arm telescopic cylinder 131 for telescoping forward and backward, an auxiliary arm rotation cylinder 132 for rotating left and right, and an auxiliary arm swing cylinder 133 for swinging up and down. The auxiliary arm swing cylinder 133 has an end motion actuator 14 for moving the end of the mechanical arm, which includes an end rotation cylinder 141 for rotating left and right.

[0047] A tool changing mechanism is provided at the action end of the end rotary cylinder 141 at the end of the robotic arm. The tool changing mechanism includes a gripping action actuator for actuating the gripping mechanism and a bolt disassembly motor for disassembling and assembling bolts; the gripping action actuator includes an upper clamping cylinder 151 and a lower clamping cylinder 152 for clamping the tool; the bolt disassembly motor includes a left hydraulic motor 161 and a right hydraulic motor 162.

[0048] In this embodiment, the movement of the ground rail platform of the tunnel boring machine tool changing robot on the ground rail and the extension and retraction of the main arm telescopic cylinder 121 constitute the first degree of freedom of the tool changing robot. The first degree of freedom includes two movable joints: the movement of the ground rail platform on the ground rail and the extension and retraction of the main arm telescopic cylinder 121; the rotation joint of the main arm rotary cylinder 122 constitutes the second degree of freedom of the tool changing robot; the swing joint of the main arm swing cylinder 123 constitutes the third degree of freedom of the tool changing robot; the telescopic joint of the auxiliary arm telescopic cylinder 131 constitutes the fourth degree of freedom of the tool changing robot; the rotation joint of the auxiliary arm rotary cylinder 132 constitutes the fifth degree of freedom of the tool changing robot; the swing joint of the auxiliary arm swing cylinder 133 constitutes the sixth degree of freedom of the tool changing robot; the rotation joint of the end rotary cylinder 141 constitutes the seventh degree of freedom of the tool changing robot.

[0049] like Figure 2 As shown, the electrical control system of the tool changing robot in this embodiment includes: a protection system 201, a power supply system 202, a human-computer interaction system 203, a main control system 204, a local control system 205, a motion control system 206, a tool changing robot mechanism 207, a sensor group 208, a monitoring system 209 and a visual recognition system 210.

[0050] The protection system includes circuit breakers, leakage protectors, fuses and emergency stop switches to prevent overcurrent and overload in the power supply system. When the current is too high or leakage occurs, the power supply can be actively disconnected for protection to avoid the risk of damaging electrical components and threatening personal safety. When an emergency occurs during the operation of the tool changing robot, pressing the emergency stop switch will stop the motion control system, and all hydraulic drive components will no longer drive the mechanical device to continue to move, so as to ensure the personal safety of the staff and further reduce safety hazards; after the fault is eliminated, the emergency stop switch will be reset and the entire system will return to normal.

[0051] The power supply system is mainly used to connect external AC power and convert AC power into DC power to power the tool changing robot. The power supply system is connected to the external three-phase five-wire 380V power AC power through a five-core cable, that is, three live wires, one neutral wire and one ground wire. At the same time, the power supply system includes a variety of voltage conversion units to provide multiple voltage levels such as AC 380V, AC 220V, DC 24V and DC 12V for the control equipment on the tool changing robot.

[0052] The human-machine interaction system is used to set the action information of the tool-changing robot and display sensor information, monitoring screen and other information. Specifically, the human-machine interaction system is located in the main control room of the tunneling equipment and is connected to the main control system through a network cable. The operator can see the real-time screen of the monitoring system through the human-machine interaction system, thereby obtaining the working status of the robot and the status of the robot's external environment, and control the tool-changing robot on the human-machine interaction system.

[0053] The main control system includes a central processing unit, a digital input unit, a digital output unit, an analog input unit, an analog output unit and a communication transmission unit, and the input and output units and the communication transmission unit are electrically connected to the central processing unit. The motion quantities of each degree of freedom of the tool-changing robot and the status information of the related joints are collected by relevant sensors and input through the communication module (communication transmission unit) and the input module (digital input unit, analog input unit); all instructions of the tool-changing robot are input by the operator through the human-computer interaction system, and after being processed by the central processing unit in combination with the motion quantities of each degree of freedom and other related information, the instructions are sent to other systems through the output module (digital output unit, analog output unit) and the communication module (communication transmission unit), thereby controlling the coordinated action of the entire tool-changing robot.

[0054] Specifically, the digital input unit is electrically connected to the signal output end of the digital sensor to read the limit signal and fault detection signal of the robot; the digital output unit is electrically connected to the control signal input end of multiple hydraulic valve controllers through multiple relays, and the communication data includes enable instructions, disable instructions and reversing instructions; the analog input unit is electrically connected to the signal output end of the analog sensor to collect analog signals from the pressure sensor, temperature sensor and humidity sensor and convert them into corresponding pressure, temperature and humidity information; the analog output unit is electrically connected to the signal input end of the proportional valve amplifier, and the amplifier amplifies the signal and transmits it to the solenoid coil of the proportional valve, and adjusts the valve core opening by adjusting the current of the solenoid coil of the proportional valve, thereby adjusting the pressure or flow; the communication transmission unit uses the CAN bus architecture, and the central processing unit processes the control instructions and sensor information, generates action execution control instructions, and connects and sends the control instructions to the proportional servo valve group in the motion control system through the communication transmission unit, thereby controlling the corresponding tool changing robot mechanism.

[0055] The motion control system is used to drive each joint to control the basic movements of the tool changing robot, including walking, telescopic, swinging, rotating, etc. The motion control system includes a servo driver, a proportional servo valve group, a gripper cylinder proportional valve group, and a hydraulic motor proportional valve group. Among them, the servo driver is used to control the rotation direction, rotation speed, rotation acceleration, etc. of the ground rail servo motor. The servo motor is equipped with a high-precision encoder inside, so as to accurately control the forward and backward movement of the ground rail walking mechanism of the tool changing robot; the proportional servo valve group is used to control the movements of the main arm action actuator, the auxiliary arm action actuator, and the end action actuator, including the main arm telescopic proportional servo valve, the main arm rotation proportional servo valve, the main arm swing proportional servo valve, the auxiliary arm telescopic proportional servo valve, the auxiliary arm rotation proportional servo valve, the auxiliary arm swing proportional servo valve, and the end rotation proportional servo valve.

[0056] In an embodiment of the present invention, the proportional servo valve is provided with an integrated axis motion control card (hereinafter referred to as the axis card), which has a communication interface and a sensor interface. The sensor and other signal detection devices can be directly connected to the axis card of the proportional servo valve. The axis card collects and processes the signal and compares it with the command signal sent by the host computer to achieve high-precision closed-loop control; the jaw cylinder proportional valve group is used to control the movement of the jaw cylinder, including an upper jaw cylinder proportional valve for controlling the movement of the upper jaw cylinder and a lower jaw cylinder proportional valve for controlling the movement of the lower jaw cylinder; the hydraulic motor proportional valve group is used to control the movement of the bolt disassembly and assembly motor, including a left hydraulic motor proportional valve for controlling the movement of the left motor and a right hydraulic motor proportional valve for controlling the movement of the right motor.

[0057] like Figure 3The figure shows the connection diagram of the proportional servo valve group. The communication terminals of the axis motion control cards of the proportional servo valves with integrated axis cards are connected in series to form a cascaded CAN communication bus. The motion detection unit and pressure detection unit corresponding to the same joint are connected to the axis motion control card of the proportional servo valve corresponding to the joint. Each axis motion control card forms a communication site that can be forwarded. The central processing unit identifies the motion information and pressure information of different active parts (joints) by identifying which communication site the different motion information and pressure information come from, thereby realizing precise adjustment of different active parts (joints).

[0058] Specifically, each axis motion control card has an IN communication terminal and an OUT communication terminal for transmitting data, wherein the IN communication terminal of one axis motion control card is connected to the communication transmission unit, and the OUT communication terminal of the axis motion control card is connected to the IN communication terminal of another axis motion control card, so that the communication terminals of the two axis motion control cards are connected in series, and the communication terminals of multiple axis motion control cards are connected in series with each other, so that all axis motion control cards are connected to the communication transmission unit through the CAN bus. According to the transmission characteristics of the CAN bus, a 120Ω terminal resistor needs to be installed at the end of the CAN bus to improve the signal quality and anti-interference ability. In addition, multiple axis motion control cards have a sensor interface for reading sensor information, and the action detection device and pressure detection device of the hydraulic drive can be directly connected to the axis card of the corresponding proportional servo valve. The integrated axis card of the proportional servo valve performs signal processing and compares it with the command signal sent by the main control system to achieve high-precision closed-loop control, without the need for the host computer to perform position closed-loop control, and the response is faster and the accuracy is higher. Since each axis motion control card can constitute a communication site, communication between all communication sites and the communication transmission unit can be achieved by connecting all communication sites in series and then connecting them to the CAN bus, and there is no need to limit the series connection order between multiple communication sites. Therefore, the present invention can greatly reduce the wiring between the control cabinet and the robot body, has a high degree of freedom in wiring, and will not cause wiring to be impossible due to interference from the tunnel boring machine structure, and wiring errors are not prone to occur.

[0059] The local control system includes a button component and an indicator light component, which are installed on the front panel of the tool-changing robot control cabinet and are used to perform some simple operations. The control cabinet can be, for example, a control cabinet in which the components of the main control system are set. The button component is installed on the front panel of the control cabinet, and can realize some local operations of the tool-changing robot, including switch control of the camera, light source, water spray, and air jet, etc. The indicator light component is also installed on the front panel of the control cabinet, and can indicate information such as the working status of the power supply and the working status of the proportional servo valve on the robot body.

[0060] The setting of the sensor group can ensure the normal operation of the tool changing robot. By detecting the displacement, angle, oil pressure and other state parameters of each hydraulic cylinder, it can realize the precise control of each part of the mechanical structure, and also provide some safety assistance. The sensor group includes a proximity switch group, a group A motion detection unit and a group A pressure detection unit, a group B motion detection unit and a group B pressure detection unit, and a group C motion detection unit and a group C pressure detection unit.

[0061] Among them, the proximity switch group includes a front proximity switch and a rear proximity switch for the ground rail, which are respectively installed at the front and rear ends of the robot ground rail and are used to detect the position of the tool changing robot on the ground rail. When the tool changing robot base (ground rail platform) reaches the detection range of the proximity switch, the signal at the output end of the proximity switch changes from a low level to a high level and is transmitted to the main control system, which performs logical processing and limits the movement of the tool changing robot on the ground rail to avoid collision between the robot and objects in front and behind.

[0062] A group of motion detection units and A group of pressure detection units are used to detect the motion information and pressure information of the main arm motion actuator, the auxiliary arm motion actuator and the end motion actuator.

[0063] The motion detection unit of group A includes an angle encoder and a displacement sensor. The motion information includes angle information and displacement information. The angle encoder is used to detect the swing or rotation angle of the hydraulic drive component and generate angle information. The displacement sensor is used to detect the extension and retraction length of the hydraulic drive component and generate displacement information.

[0064] Specifically, Group A motion detection units have seven motion detection units, which respectively detect the extension length of the main arm telescopic cylinder, the rotation angle of the main arm rotation cylinder, the swing angle of the main arm swing cylinder, the extension length of the auxiliary arm telescopic cylinder, the rotation angle of the auxiliary arm rotation cylinder, the swing angle of the auxiliary arm swing cylinder and the rotation angle of the terminal rotary cylinder.

[0065] The pressure detection unit of group A is used to detect the pressure of the main arm action actuator, the auxiliary arm action actuator and the terminal action actuator and generate pressure information. The pressure information is fed back to the main control system, which compares the pressure information with the set pressure upper limit value, and issues a protection instruction to the motion control system when the pressure information is greater than the pressure upper limit value. The motion control system controls the corresponding hydraulic drive to stop moving according to the protection instruction. When the movement of the hydraulic drive is hindered (such as a failure of the hydraulic drive or encountering other obstacles), if hydraulic oil continues to be injected into the hydraulic drive, the pressure of the hydraulic drive will continue to increase. Therefore, the pressure information of the hydraulic drive is fed back to the main control system through the pressure detection unit, so that the main control system can judge the working state of the hydraulic drive through the pressure information, and issue a protection instruction when the pressure exceeds the set pressure upper limit value to stop injecting hydraulic oil into the hydraulic drive, thereby avoiding damage to the hydraulic drive.

[0066] Specifically, the pressure detection unit of group A includes fourteen pressure sensors, which are respectively installed at the oil inlets and oil return ports of seven hydraulic drive components.

[0067] The B-group motion detection unit and the B-group pressure detection unit are used to detect the motion information and pressure information of the gripping action actuator. The B-group motion detection unit includes two displacement sensors for detecting the length of the upper and lower clamping jaw cylinders and generating displacement information. The B-group pressure detection unit is used to detect the pressure of the gripping action actuator and generate pressure information.

[0068] The C group motion detection unit and the C group pressure detection unit are used to detect the motion information and pressure information of the gripping action actuator. The C group motion detection unit includes two displacement sensors for detecting the length of the upper and lower clamping jaw cylinders and generating displacement information. The C group pressure detection unit is used to detect the pressure of the gripping action actuator and generate pressure information.

[0069] The monitoring system includes multiple monitoring units and multiple monitoring lighting sources. The monitoring system can directly obtain the environmental information around the tool changing robot and the position and posture information of the tool changing robot. The multiple monitoring units include a left front monitoring unit, a left rear monitoring unit, a right front monitoring unit and a right rear monitoring unit arranged on the cabin of the tool changing robot. The left front monitoring unit and the right front monitoring unit are used to obtain the field of view in front of the tool changing robot body; the left rear monitoring unit and the right rear monitoring unit are used to obtain the field of view behind the tool changing robot body. Since the front of the tool changing robot is the cutterhead of the shield machine and the excavated face, the closed space causes the tool changing robot to basically work in a lightless environment, so a lighting system is required to provide auxiliary lighting for it. The monitoring lighting sources are installed around the cabin of the tool changing robot, including a left front light source, a left rear light source, a right front light source and a right rear light source, so that the operator can correctly control it according to the monitoring screen, and at the same time, the posture information of the tool changing robot can be obtained, which is convenient for the operator to control.

[0070] The visual recognition system includes a visual recognition unit, a visual lighting source, a water spray switch valve, and an air jet switch valve. The visual recognition unit uses an industrial camera and is installed at the front end of the robot. The industrial camera is moved to the image acquisition area by adjusting the tool change robot to acquire the image of the tool box. After that, the camera is calibrated with internal and external parameters. The internal calibration is used for image distortion correction, and the external calibration is used to determine the transformation relationship between the camera coordinate system and the robot coordinate system. The camera can correct the image distortion according to the calibration information, and match and locate the feature points in combination with the template matching algorithm of the image, obtain the coordinates of the tool box in this image information, and obtain the tool box posture information in the robot coordinates in combination with the camera calibration results. The robot automatically changes the tool according to the above information; the visual lighting source is installed at the front end of the tool change robot to provide sufficient lighting for the industrial camera so that it can complete visual inspection.

[0071] Since industrial cameras are inevitably stained with mud and water during visual inspection, nozzles are installed on both sides of the camera lens to clean the lens. A water spray switch valve and an air jet switch valve are set on the outside of the tool changer robot, and connected to the nozzle next to the industrial camera through a pipeline. The lens is sprayed with water to remove mud and then sprayed with air to remove water droplets, thereby ensuring the cleanliness of the camera lens. The opening and closing of the water spray switch valve and the air jet switch valve can be controlled locally or on the human-machine interface.

[0072] The electrical control system of the tool-changing robot in this embodiment also includes a control cabinet, in which the protection system, power supply system, main control system and local control system are installed in the control cabinet to avoid external interference and damage, and the rest are placed outside the control cabinet. Among them, the motion control system, sensor group and visual recognition system are installed on the tool-changing robot body, the monitoring system is installed around the tool-changing robot, and the human-machine interaction interface is installed in the shield main control room.

[0073] To sum up, the electrical control system of the tool changing robot in this embodiment includes: a protection system, which protects electrical equipment and operators to avoid damage to electrical equipment and endangerment to personal safety; a power supply system, which provides multiple voltages to provide stable power supply for the electrical equipment of the tool changing robot; a human-computer interaction system, which provides an operation and monitoring platform for the operator; a main control system, which performs logic processing, data storage and signal output; a local control system, which performs basic local control of the tool changing robot; a motion control system, which controls the basic movements of the mechanical structure of the tool changing robot; a sensor group, which realizes precise control of the mechanical structure of each part by detecting the displacement, angle, oil pressure and other state parameters of each hydraulic cylinder, and can also provide some safety assistance; a monitoring system, which obtains the posture information of the tool changing robot and the environmental information around the tool changing robot, so as to facilitate the operator to control; a visual recognition system, which obtains the image information of the tool box and visually guides the tool changing robot.

[0074] In the electrical control system of the tool-changing robot in the embodiment of the present invention, the CAN bus is used to improve the real-time performance and anti-interference ability of the control system. A proportional servo valve with an integrated axis motion control card is respectively set for each main joint of the tool-changing robot. The axis motion control card is provided with a communication interface. It is only necessary to connect the communication interfaces of all axis cards in series and finally connect the CAN communication module to complete the communication connection. At the same time, the axis card is also provided with a sensor interface. The motion detection device and the pressure detection device of the hydraulic drive can be directly connected to the axis card of the corresponding proportional servo valve. The integrated axis card of the proportional servo valve performs signal processing and compares it with the command signal to achieve high-precision closed-loop control. The upper computer does not need to perform position closed-loop control, and the response is faster and the accuracy is higher. The setting of this system solves the problems of slow response speed, low control accuracy and poor anti-interference ability of traditional solenoid valve control, and provides a guarantee for realizing robot tool changing. At the same time, a large number of IO modules, relays, amplifiers and other equipment are no longer needed, which can greatly reduce the wiring harness between the robot body and the control cabinet, reduce the system failure rate, and is more suitable for the narrow and harsh environment of tunnels.

[0075] In addition, in the electrical control system of the tool changing robot of the present invention, a visual recognition system is provided to realize automatic tool changing of the robot. The visual recognition system is installed at the front end of the tool changing robot, and the industrial camera is moved to the image acquisition area by adjusting the robot to acquire the image of the tool box. The camera can perform distortion correction on the image according to the calibration information, and match and locate the feature points in combination with the template matching algorithm of the image to obtain the posture information of the tool box under the robot coordinates. The tool changing robot performs path planning based on this information to complete automatic tool changing. The setting of this system solves the key problem of "automatic tool changing" that has long been impossible to realize, that is, the inability to obtain accurate posture information of the tool box makes it difficult to realize automatic tool changing through robot operation. At the same time, water spray cleaning and air jet cleaning devices are provided in the visual recognition system, which is more applicable in harsh tunnel environments.

[0076] Therefore, the robot electrical control system of the present invention, when used for a tool changing robot of a tunnel boring machine, can realize high-precision and automatic control of the tool changing robot of a full-section tunnel boring machine, and can improve the efficiency and safety of tool changing. In addition, through the tool changing robot electrical control system of the present invention, the position and posture of the tool can be automatically detected, and visual guidance can be provided to the tool changing robot, reducing manual operation and further improving the efficiency of tool changing.

Claims

1. An electrical control system for a robot for a tunnel boring machine, characterized in that: It includes a main control system, a motion control system, an operating unit for controlling the robot's movements, and a sensor group for detecting the state parameters of multiple degrees of freedom of the robot; the motion control system includes a joint drive mechanism for each degree of freedom of the robot; the joint drive mechanism for each degree of freedom is correspondingly connected to each axis motion control card; the sensor corresponding to each degree of freedom is connected to the axis motion control card corresponding to the degree of freedom; The main control system includes an input unit for collecting data from each sensor in the sensor group, an output unit for outputting control instructions to the joint drive mechanism, and a communication unit; the input unit and the output unit are connected to each sensor through the communication unit to collect state parameters of each degree of freedom, and are also connected to the axis motion control card corresponding to each joint drive mechanism through the communication unit to realize the control of each joint action; The axis motion control card collects the state parameters of the corresponding degree of freedom and compares them with the command signal of the joint drive mechanism corresponding to the degree of freedom to achieve closed-loop control of the joint drive mechanism of the degree of freedom.

2. The electrical control system of the robot for a tunnel boring machine according to claim 1, characterized in that: The communication unit includes a CAN communication network, and the input unit, the output unit, each joint driving mechanism and each sensor are connected to the CAN communication network, and data is exchanged through the CAN communication network.

3. The electrical control system of the robot for a tunnel boring machine according to claim 2, characterized in that: The CAN communication network includes a plurality of axis motion control cards whose communication terminals are cascaded in sequence.

4. The electrical control system of the robot for a tunnel boring machine according to claim 3, characterized in that: The sensor includes a hydraulic pressure sensor corresponding to the joint driving mechanism and a motion detection unit corresponding to the degree of freedom, and the state parameter includes the hydraulic pressure of the joint driving mechanism corresponding to the degree of freedom and the motion amount of the corresponding degree of freedom.

5. The electrical control system of the robot for a tunnel boring machine according to claim 4, characterized in that: The joint drive mechanism includes a proportional valve for adjusting the corresponding hydraulic pressure; the axis motion control card is connected to the proportional valve of the corresponding joint drive mechanism, and the movement amount of the corresponding degree of freedom is controlled by adjusting the opening of the proportional valve, and the movement of the joint of the corresponding degree of freedom is stopped after the movement amount of the corresponding degree of freedom reaches the target value.

6. The electrical control system of the robot for a tunnel boring machine according to claim 5, characterized in that: The axis motion control card collects the hydraulic pressure of the joint drive mechanism corresponding to the degree of freedom, and stops the movement of the joint of the degree of freedom after the pressure reaches a set value.

7. The electrical control system of the robot for a tunnel boring machine according to claim 1, characterized in that: It also includes a robotic monitoring system and a visual recognition system; The robot monitoring system includes a plurality of monitoring units and monitoring lighting sources; the monitoring unit includes a forward monitoring camera for obtaining the robot's end position and forward field of view and a backward monitoring camera for obtaining the robot's backward field of view; the monitoring lighting source is used to illuminate the robot's surroundings; The visual recognition system includes a visual recognition unit, a visual lighting source, a water spray device and an air jet device; the visual recognition unit is installed at the end of the robot, and is used to collect images through an industrial camera and perform image recognition on the collected images. The visual lighting source is set at the end of the robot, and is used to provide fill light when the industrial camera collects images; the water spray device and the air jet device are set toward the lens of the industrial camera, and are used to spray water to remove sludge on the lens and spray air to remove water droplets on the lens.

8. The electrical control system of the robot for a tunnel boring machine according to claim 7, characterized in that: The operating unit includes a human-machine interaction system arranged in the main control room of the tunnel boring machine, and a local control system arranged at the robot control cabinet; The human-machine interaction system is connected to the main control system and displays sensor information and real-time images collected by the monitoring unit, and controls the robot according to the interaction; The local control system includes a control button component and an indicator light component. The control button component is used to realize local operation control of the robot; the indicator light component is used to indicate the working status of the robot power supply and the working status of each joint driving mechanism.

9. The electrical control system of the robot for a tunnel boring machine according to claim 8, characterized in that: It also includes a protection system, which includes a circuit breaker and an emergency stop switch; after detecting that the current exceeds a set threshold or leakage occurs, the power supply is disconnected by the circuit breaker to achieve protection; the emergency stop switch is used to control the motion control system to stop working when it is pressed, and each degree of freedom no longer moves.

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