Intelligent monitoring rail robot for electric power inspection of underground cable tunnel

Abstract

The underground cable tunnel electric power inspection intelligent monitoring rail robot is improved on the basis of an original crossing obstacle type inspection robot, mechanical structures for a robot body and a rail are constructed respectively, and the robot comprises a walking mechanism, a rotating mechanism, a pressing mechanism, a control box, an inspection operation arm and a tail end detector. A specific positioning method of the inspection robot is designed, and meanwhile the communication problem of the inspection robot is solved. The inspection blind area is calculated, the obstacle crossing technology of the inspection robot is designed, the tunnel fireproof door is transformed, and the inspection blind area possibly existing in the process that the inspection robot inspects the cable tunnel is eliminated. A simple three-dimensional model of the inspection robot is established, meanwhile, a cable tunnel model is established, kinematics simulation analysis is carried out on the robot, the robot can operate all day long, cable tunnel inspection is reliable and efficient, and the adaptability to severe environments is higher.

Description

Technical Field

[0001] The present application relates to a cable tunnel power inspection and monitoring track-mounted robot, and in particular to an underground cable tunnel power inspection intelligent monitoring track-mounted robot, belonging to the technical field of power inspection and monitoring robots. Background Art

[0002] With the continuous application of urban underground cable tunnels, safety accidents in underground cable tunnels have occurred frequently, causing major property losses, power outages and even major safety accidents. Therefore, the inspection of underground cable tunnels has become increasingly important. If manual inspection is adopted, the traditional manual inspection has inconvenient communication and a poor inspection environment. At the same time, it is difficult to ensure the safety of the inspectors, and in some special cases it may even endanger their lives. The traditional manual inspection method is becoming increasingly difficult to meet the requirements of modern society, and all the monitoring systems of the cable tunnels themselves have many flaws and defects. Under such a background, using robots to replace people for cable tunnel inspection has certain advantages. The robot inspection can operate around the clock and has a stronger adaptability to harsh environments. Therefore, the development of a robot that can be used for underground cable tunnel inspection has significant practical significance. However, the existing technology is mostly focused on ground mobile robots for cable tunnel inspection.

[0003] The cause of cable tunnel fire and explosion is local heating and the ignition point of flammable gas or other objects. In addition, the presence of a large amount of flammable gas will instantly cause a fire, which will cause the violent expansion of the gas and cause an explosion. The part where the cable is heated and the temperature rises locally should be the cable joint. It may also be caused by potential quality or construction hazards in the cable body, or by corona sparks or short circuits. There is a high possibility of flammable gas in the tunnel environment. If the local ventilation is not smooth, the concentration of flammable gas will increase. Therefore, the local heating and flammable gas, water and water accumulation, temperature and humidity, external force damage, theft of manhole covers, and the surface state of the tunnel body, cables and their structures in real time are monitored. Among them, the focus should be on toxic and harmful gases and flammable gases, temperature and humidity in the cable tunnel, and the surface state of the cable.

[0004] Due to the influence of many factors such as construction costs, temperature detection is currently only implemented in a few places with joints in cable tunnels, and combustible gas detection is only arranged in a few tunnels and a few points. Visible light cameras are distributed in the tunnel for video monitoring. The essential deficiencies of this distributed detection method include: first, the effective area of ​​​​distributed detection cannot effectively cover the entire cable tunnel, resulting in a dead zone or blind spot that is much larger than the detection area; second, the detection means are incomplete and the detection technology needs to be improved. When the robot travels back and forth in the tunnel, it is impossible to implement periodic traversal inspections of the tunnel. There is a lack of reasonable arrangement of inspection cycles, and it is impossible to solve the problems of detection dead zones and incompleteness of detection means in the current cable tunnel detection architecture, and it is impossible to timely discover faults and safety hazards in various local locations of the cable tunnel.

[0005] The existing technology of cable tunnel operation status detection is still a manual inspection method, and distributed video and temperature measurement are only used as auxiliary means. In addition, the cable tunnel monitoring system has certain inspection blind spots. Due to the existence of this inspection blind spot, some cable tunnel areas cannot be detected even if dangerous conditions occur. This is a huge hidden danger for underground cable tunnels. On the other hand, the detection and early warning of flammable and toxic gases are still blank.

[0006] The problems that the cable tunnel inspection and monitoring robot of the prior art needs to solve and the key technical difficulties of this application include:

[0007] (1) The safety threat of cable tunnels lies in the fact that fires can cause violent expansion of gases and lead to explosions. The cable joints are the places where local heating and continuous temperature rise occur. In tunnel environments, there is a high possibility of generating flammable gases. If local ventilation is poor, the concentration of flammable gases will increase. However, existing technologies cannot monitor local heating and flammable gases, water and accumulated water, temperature and humidity, external damage, stolen manhole covers, and the surface conditions of the tunnel body, cables and their structures in real time. They also do not focus on toxic and harmful gases and flammable gases, temperature and humidity in cable tunnels, and cable surface conditions. Most of the existing underground cable tunnels are inspected manually. However, the traditional manual inspection has inconvenient communication and poor inspection environment. It is difficult to ensure the safety of the inspectors and may even endanger their lives in some special cases. The manual inspection method is increasingly difficult to meet the requirements of modern society. The monitoring systems of the cable tunnels themselves have many flaws and defects. Under such circumstances, it is advantageous to use robots to replace humans for cable tunnel inspection. Robot inspection can operate around the clock and has stronger adaptability to harsh environments. Therefore, it is urgent to develop a robot that can be used for underground cable tunnel inspection. However, the existing technologies are mostly focused on ground mobile robots for cable tunnel inspection.

[0008] (2) The existing technology of cable tunnel operation status detection is still mainly manual inspection, and distributed video and temperature measurement are only used as auxiliary means. In addition, the cable tunnel monitoring system has certain inspection blind spots, so that even if dangerous situations occur in some cable tunnel areas, they cannot be detected. This is a huge hidden danger for underground cable tunnels. On the other hand, the detection and early warning of flammable gases and toxic gases are still blank. At present, temperature detection is only implemented in a few places with joints in cable tunnels, and flammable gas detection is only arranged in a few tunnels and a few points. Visible light cameras are distributed in the tunnel for video monitoring, which has obvious shortcomings: First, the effective area of ​​distributed detection cannot effectively cover the entire cable tunnel, resulting in the dead zone or blind zone of detection being much larger than the detection area; second, the detection means are incomplete and the detection technology needs to be improved. When the robot is driving back and forth in the tunnel, it is impossible to implement periodic traversal inspection of the tunnel. There is a lack of reasonable arrangement of the inspection cycle, and it is impossible to solve the problems of detection dead zones and incomplete detection means in the current cable tunnel detection architecture, and it is impossible to timely discover the faults and safety hazards of various local locations of the cable tunnel.

[0009] (3) Many parts of the inspection robots in the prior art are exposed to the outside, and the overall waterproof performance is poor. If the inspection robot works in a cable tunnel where water seepage may occur, it may even be unable to complete the inspection of the cable. The robot is large in size, cannot conduct autonomous inspections and requires manual remote control, has a short battery life, and the working range of the inspection instrument is limited, resulting in a large inspection blind area and cannot adapt to water accumulation environments. There is also the problem that the robot has poor obstacle crossing ability and can only work in large cable tunnels with relatively flat ground. In addition, some existing inspection robots have high track costs, complex installation, large inspection blind areas, and can only work in specific working environments. They cannot adapt to complex working environments, such as turns, fire doors and shafts, and cannot adapt to cable tunnels and cable trenches of different structural forms and structural sizes; the inspection blind area of ​​the inspection instrument is large, and even the blind area is far larger than its effective inspection area. It cannot adapt to the complex environment in the cable tunnel, let alone the specific structural form and structural size of the cable tunnel. Therefore, there is an urgent need for a reliable and efficient inspection robot that can adapt to complex working environments, such as turns, fire doors and shafts, as well as cable tunnels and cable trenches of different structural forms and sizes. Summary of the invention

[0010] The present application has carried out a relatively detailed research and development design of the cable tunnel inspection robot, including the construction of the cable tunnel monitoring system, the calculation of the inspection blind area of ​​the inspection robot, and the communication and positioning of the cable tunnel inspection robot. The sensors used include gas sensors, temperature and humidity sensors, and ultrasonic sensors, etc., and are equipped with infrared thermal imagers and pan-tilt cameras. The kinematic simulation and analysis of the inspection robot are carried out using relevant application software. The track-type inspection robot of the present application can adapt to the current requirements for comprehensive, all-weather, and efficient inspection of cable tunnels. The designed track is suitable for specific cable tunnel structures and their relevant national standards. At the same time, the robot has a certain climbing ability. In addition, due to the high humidity in the cable tunnel, the robot has a strong waterproof performance. At the same time, due to the large number of cables in the cable tunnel, the robot adopts a highly reliable wireless communication method to achieve communication in the cable tunnel. The robot of the present application can monitor the local heating and flammable gas, water and water accumulation, temperature and humidity, external force damage, theft of manhole covers, and the surface state of the tunnel body, cables and their structures in real time, and can focus on toxic and harmful gases and flammable gases, temperature and humidity in the cable tunnel, and the surface state of the cable.

[0011] In order to achieve the above technical effects, the technical solutions adopted in this application are as follows:

[0012] Tracked intelligent monitoring robot for power inspection in underground cable tunnels. The track of the tracked inspection robot is set up on the top of the cable tunnel. The inspection robot is based on the improvement of the obstacle-crossing inspection robot. The inspection modes are divided into three types: conventional inspection, fixed-point inspection and emergency inspection. An intelligent robot inspection plan is established, and the inspection blind spots are eliminated by calculation. The tunnel fire doors are renovated. At the same time, methods for the inspection robot to pass through straight sections and curves are constructed respectively. The positioning and communication solutions of the inspection robot are established. Infrared thermal imagers, visible light cameras and various sensors are installed at the end of the inspection arm. The kinematic simulation of the inspection robot is carried out to obtain the relationship between important parameters, determine the conditions that the walking speed of the inspection robot and the angular velocity of the inspection arm need to meet, and avoid the occurrence of inspection blind spots.

[0013] 1) Construct a rail-type cable tunnel inspection robot, which is improved on the basis of the original obstacle-crossing inspection robot, and establish the mechanical structure of the robot body and the track respectively, including the walking mechanism, the rotating mechanism, the clamping mechanism, the control box, the inspection working arm and the terminal detector. The terminal detection instrument includes a temperature and humidity sensor, a combustible gas sensor, an infrared thermal imager, an ultrasonic sensor, and is equipped with an infrared thermal imager and a pan-tilt camera;

[0014] 2) Establish the mobile positioning and communication method of the inspection robot, use RFID wireless radio frequency technology for positioning, set up an infinite bridge at intervals in the cable tunnel to solve the communication problem of the inspection robot, and eliminate the inspection blind spots in the process of the robot inspecting the cable tunnel by calculating the inspection blind spots. Establish the obstacle-passing method of the inspection robot and transform the tunnel fire door;

[0015] 3) Establish a three-dimensional model of the inspection robot, establish a cable tunnel model, and use SolidWorksmotion to perform kinematic simulation and analysis on the robot to specifically express the robot inspection process.

[0016] Preferably, based on the improvement of the obstacle-crossing inspection robot: the cable tunnel inspection robot is improved on the basis of the obstacle-crossing robot, including the following parts: a clamping wheel, a clamping joint, a moving joint, a walking wheel, a swivel joint, and a chassis, to achieve the following movements: the rolling of the walking wheel results in the rolling of the robot relative to the bottom line, and the robot travels along the steel pipe track, and an inspection working arm is added. At the same time, various sensors are carried at the end of the inspection working arm, including temperature and humidity sensors and combustible gas sensors, and a visible light camera is also carried to identify surface defects of the cable; the robot's driving path and its obstacle crossing characteristics are: the suspended hanging plate and the upper lifting wire clamp that block the robot from passing are respectively designed and transformed into a lower lifting C-type structure hanging plate and a lower lifting wire clamp that the robot rolls through, and the ground wire tension tower head that the robot cannot pass directly is added with a rolling bridge at both ends, and a robot proximity detection structure and a charging docking structure are added to the bottom surface of the lower lifting C-type hanging plate. For the anti-vibration hammer, parallel groove wire clamp, suspension and tension, the robot uses a rolling method to pass through all obstacles on the ground wire.

[0017] Preferably, the overhead track structure scheme: the cables are placed on the cable bracket, the optical cable is placed on the top layer, and no inspection is required. The steel tube track is erected on the upper part of the tunnel and supported by a bracket. One end of the bracket is connected to the top of the tunnel. The length of the steel tube track is not less than 500 meters, and the track is at the upper end of the cable tunnel. It is planned to use an overhead steel tube track as the robot's walking path, and the steel tube track sections are connected by barrier-free pin shafts. Every section of the length is supported by a bracket installed on the top surface of the tunnel. The bracket and the connecting pins between the sections are connected to form a barrier-free structure for the robot to roll. The size of the overhead steel tube track is determined according to the specific cable tunnel-related construction standards.

[0018] Preferably, the intelligent robot inspection solution: an overhead track inspection robot solution is adopted, and the inspection robot generally includes the following parts: a walking mechanism, a clamping mechanism, a slewing mechanism, a control box, an inspection arm and an end detector, and the inspection robot performs inspections on a steel pipe track, and the track is erected on the top of the cable tunnel;

[0019] There are three inspection modes for the inspection robot: routine inspection, fixed-point inspection and emergency inspection. During routine inspection, the inspection robot walks while the detection arm reciprocates within the α angle range. Assume that the linear speed of the mobile robot is v, the angular velocity of the reciprocating rotation of the detection operation is ±ω, the field of view of the camera on the inspection arm on the horizontal plane is θ, and the width of the tunnel is L. In the routine inspection operation mode, the motion trajectory of the two end points of the detection arm is a cycloid, and the pitch of the cycloid is the distance to be inspected by the detection arm in one reciprocating cycle and all the targets it contains. At this time, the detection equipment carried by the two arms detects the cables and environmental conditions on both sides respectively.

[0020] d is the distance the robot moves when the inspection arm rotates from top to bottom once, so that the field of view reaches all the targets in the tunnel, and the following relationship is obtained:

[0021]

[0022] The relationship between θ, v, and ω is determined by the above formula;

[0023] Preferably, conventional inspection is the main inspection method. In order to achieve full coverage of the field of view of the infrared thermal imager or visible light camera during the robot inspection process, the inspection speed of the inspection robot must have a critical value. When the inspection speed of the inspection robot exceeds this critical value, the field of view of the camera cannot achieve full coverage of the cables to be inspected in the cable tunnel, and an inspection blind spot will be generated. There are certain restrictions on the speed of the inspection robot and the rotation angle of the working arm.

[0024] h i The cable area to be inspected. The top layer inside the cable tunnel is generally equipped with optical cables. The top layer does not need to be inspected. The area to be inspected is from the second layer to the bottom layer. i The width of the cable tunnel that needs to be inspected must meet full coverage within the vertical inspection range:

[0025]

[0026] Where ly1 is the vertical length between a point at the end of the inspection arm of the inspection robot and the center of the inspection area to be inspected, and ly2 is the vertical length between a point at the end of the working arm of the inspection robot and the highest point of the inspection cable area;

[0027] At the same time, it must be satisfied that within one inspection cycle of the robot, the distance the robot travels is less than or equal to the length of the field of view, that is:

[0028] S=vT≤l x Formula 4

[0029]

[0030] Where S is the distance the robot travels when the patrol arm completes one cycle, V is the robot's walking speed, T is one patrol cycle, that is, the time it takes for the patrol arm to complete one cycle, and α is the rotation angle of the patrol arm;

[0031] α and β are the horizontal and vertical field of view angles of the camera, respectively. Combining equations 3 and 4, we can get:

[0032]

[0033] Among them l a is the length of the inspection arm. Substituting equations 7 and 8 into equation 3, we can obtain the critical condition of the rotation angle:

[0034]

[0035] Combining the above formula, we can get the critical speed condition:

[0036]

[0037] The critical condition of the robot's driving speed is obtained from Formula 10, that is, the robot's walking speed cannot exceed the critical value. Once the inspection robot's walking speed exceeds the critical value, the camera's field of view will not be able to fully cover the cable inspection area, and an inspection blind spot will be created. Therefore, the robot's driving speed cannot exceed the critical value, which can be calculated by Formula 10.

[0038] Preferably, the inspection robot can also perform fixed-point inspection, that is, the inspection robot stops walking, and the detection working arm rotates back and forth within the α angle range, and the trajectory of its two end points is an arc. This method can achieve detailed inspection of designated sections or targets, which is suitable for key areas or suspected fault troubleshooting.

[0039] Preferably, the emergency inspection is that the mobile robot quickly reaches the designated location and then conducts a special inspection on it. No inspection is performed during the rapid arrival process. The special inspection includes the sound detection of water seepage and corona, and the detection of smoke and toxic gases. This inspection method is suitable for the robot to be away from the designated area for emergency inspection. The visible light and infrared equipment carried by the two arms detect the same side, and the two sides are performed successively;

[0040] The inspection robot travels along the overhead steel pipe track. The robot is driven by two running wheels. The steel pipe track is supported by a bracket. The steel pipe sections are connected by internal pins. The bracket and its internal connection structure between sections are designed appropriately so that the bracket and its internal connection structure do not constitute obstacles to the rolling of the running wheels. The robot can continuously roll to any position on the track or tunnel.

[0041] The mobile robot platform is a mobile robot with two wheel-arm composites and arms with limited rotation pairs around a vertical axis. Specifically, each arm is suspended by a walking wheel, and the two walking wheels are independently driven to roll. Each arm has a kinematic pair with limited rotation around a vertical axis. When the two rotation pairs are locked, the two mechanical arms are fixed to the frame to achieve walking along a straight track. When the rotation pairs of the two arms are in a non-locked state, turning walking on tracks with different curve radii can be achieved. When encountering a curve, the rotary axis is in a non-locked, under-driven free state, and passes through the curve at a low speed. The forward direction of the wheel is driven by the track. When the robot walks on a straight section, both arms are locked, that is, in a non-free moving state.

[0042] Preferably, the fire door renovation plan: after the fire door has been renovated, when the inspection robot inspects the cable tunnel, when the inspection robot inspects near the fire door, it stops and sends information to the cable monitoring system. At this time, the cable monitoring system determines whether the fire door is open. If the fire door is not open, the fire door is opened, and the inspection robot can pass through smoothly. If the cable tunnel inspection robot can have a high inspection efficiency for the cable tunnel, the fire door will not be suddenly closed. The fire door will only be closed under extremely special circumstances. At this time, after the cable tunnel fire door is renovated, even if a sudden danger occurs, the robot can pass through smoothly and reach the designated area.

[0043] Preferably, the inspection robot communicates and positions: during the inspection process, the inspection robot uses wireless communication, and uses wired optical cable communication between the cable tunnel and the ground monitoring room. Multiple 5G wireless network communications are used between the inspection robot and the optical cable. The robot and multiple wireless network nodes on the optical cable dynamically establish point-to-point communication, that is, the robot automatically searches for network node signals, and automatically selects the one with the strongest signal strength among the searched network nodes as its current communication network. When the signal strengths of two nodes are equal, the robot's positioning is used to determine the one with the closest distance to the node. The number and distance of network nodes are determined based on the cable tunnel and the communication module selected;

[0044] The optical fiber signal is connected to the monitoring room, demodulated and sent to the computer through the access device, or transmitted from the computer to the robot through the access device. The data is bidirectional and the image is only one-way downward. Under the system management, the entire monitoring system completes the remote control operation of the robot, infrared and visible light diagnosis, combustible gas data analysis, other data analysis, and automatic update of the database in parallel. Among them, autonomous control refers to the autonomous patrol control of the inspection robot, which is loaded in the inspection robot, while the autonomous control in the monitoring system requires the modification of the autonomous control parameters of the inspection robot, or the reconfiguration of the autonomous control software for different cable tunnels.

[0045] Preferably, kinematic simulation and analysis of the inspection robot: kinematic simulation of the inspection robot is performed, using the motion module in SolidWorks, the three-dimensional model is simplified for kinematic simulation, the inspection process of the robot is simulated, and the relevant parameters are first set before the simulation;

[0046] First, set the gravity parameters. Set the direction to the negative direction of the Y axis. Use the default values. Set the entity contact and use the contact group. Use the default values ​​for other parameters. Then add the corresponding motors. Add linear motors and rotary motors at the corresponding positions.

[0047] The rotating motor used in the above application is of constant speed, the speed curve of the walking wheel is a straight line, and the angular speed of the robot's rotating arm should not be set too low to achieve full coverage of the camera's field of view to avoid blind inspection areas;

[0048] In addition, the walking speed of the inspection robot should not be too high, otherwise there will still be visual blind spots. The driving speed of the inspection robot should not exceed a critical value to achieve full coverage inspection of the cable area to be inspected.

[0049] Compared with the prior art, the innovations and advantages of this application are:

[0050] (1) The present application has developed a track-mounted robot that can be used for autonomous inspection of underground cable tunnels. The robot is improved on the basis of the original obstacle-crossing inspection robot, and the mechanical structures of the robot body and the track are constructed separately, including a walking mechanism, a rotating mechanism, a clamping mechanism, a control box, an inspection arm and a terminal detector. The terminal detection instrument includes a temperature and humidity sensor, a combustible gas sensor, an infrared thermal imager, etc. A specific method for positioning the inspection robot is proposed, and RFID wireless radio frequency technology is used for positioning. An infinite network bridge is set up at a certain distance in the cable tunnel, and the communication problem of the inspection robot is solved at the same time. The inspection blind area is calculated, the obstacle-crossing technology of the inspection robot is designed, and the tunnel fire door is modified to eliminate the inspection blind area that may exist in the inspection robot during the inspection of the cable tunnel. A simple three-dimensional model of the inspection robot is established, and a cable tunnel model is established at the same time. The robot is subjected to kinematic simulation analysis, and the robot inspection process is specifically expressed. The inspection robot can operate around the clock, and the cable tunnel inspection is reliable and efficient, and the adaptability to harsh environments is stronger.

[0051] (2) The present application has conducted a relatively detailed research and development design of the cable tunnel inspection robot, including the construction of the cable tunnel monitoring system, the calculation of the inspection blind spots of the inspection robot, and the communication and positioning of the cable tunnel inspection robot. The sensors used include gas sensors, temperature and humidity sensors, and ultrasonic sensors, etc., and are equipped with infrared thermal imagers and pan-tilt cameras. The kinematic simulation and analysis of the inspection robot are carried out using relevant application software. The track-type inspection robot of the present application can meet the current requirements for comprehensive, all-weather, and high-efficiency inspections of cable tunnels. The designed track is suitable for specific The cable tunnel structure and its relevant national standards. At the same time, the robot has a certain climbing ability. In addition, due to the high humidity in the cable tunnel, the robot has strong waterproof performance. At the same time, due to the large number of cables in the cable tunnel, the robot adopts high-reliability wireless communication means to realize communication in the cable tunnel. The robot of this application can monitor the local heating and flammable gases, water and accumulated water, temperature and humidity, external force damage, theft of manhole covers, and the surface status of the tunnel body, cables and their structures in real time, and can focus on toxic and harmful gases and flammable gases, temperature and humidity in the cable tunnel, and the surface status of cables.

[0052] (3) This application has improved the design of the autonomous inspection robot for cable tunnels from multiple angles and aspects. The track of the rail-type inspection robot is set up on the top of the cable tunnel. Compared with the ground inspection robot, the advantage of this overhead rail-type inspection robot is that it has a wider inspection range and can inspect the same cable tunnel repeatedly. The inspection robot has three inspection modes: conventional inspection, fixed-point inspection and emergency inspection. This application has detailed designs for these three inspection modes, especially for conventional inspection, the calculation of inspection blind spots, and the design of the inspection robot passing through straight sections and curves. At the same time, the positioning and communication problems of the inspection robot are solved. At the end of the inspection arm, an infrared thermal imager, a visible light camera and various sensors, including temperature and humidity sensors and gas sensors, are installed. In addition, this application also uses SolidWorksmotion to perform kinematic simulation of the inspection robot, and obtains the relationship between important parameters. Finally, it is determined that the walking speed of the inspection robot and the angular velocity of the inspection arm must meet certain conditions to avoid the occurrence of inspection blind spots. At the same time, flammable gases and toxic gases can be detected in real time and their early warning can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a schematic diagram of the inspection structure of the inspection robot on the steel pipe track.

[0054] Figure 2 This is a schematic diagram of the inspection process of the inspection robot.

[0055] Figure 3It is a schematic diagram of the inspection environment structure of the inspection robot.

[0056] Figure 4 This is a schematic diagram of the calculation of the coverage of routine inspections.

[0057] Figure 5 This is a schematic diagram of the rules for a robot to travel on a curved track.

[0058] Figure 6 It is a structural diagram of the wireless communication method of the inspection robot during the inspection process.

[0059] Figure 7 It is a schematic diagram of the catalytic combustion type detected by the inspection robot.

[0060] Figure 8 It is a schematic diagram of the physical contact setting of the inspection robot kinematic simulation. DETAILED DESCRIPTION

[0061] The following, in conjunction with the accompanying drawings, further describes the technical solution of the underground cable tunnel power inspection intelligent monitoring track robot provided by the present application, so that technical personnel in the field can better understand the present application and implement it.

[0062] With the continuous application of urban underground cable tunnels, safety accidents in underground cable tunnels continue to occur frequently. Therefore, the inspection of underground cable tunnels has become more and more important. The traditional manual inspection method is increasingly difficult to meet the requirements of modern society. The monitoring systems of the cable tunnels themselves have many flaws and defects. Therefore, it is of great practical significance to study a robot that can be used for underground cable tunnel inspection. In the past, the research of predecessors focused on the inspection of cable tunnels by ground mobile robots. This application proposes an overhead track inspection robot for cable tunnel inspection. This robot can greatly improve the inspection efficiency of cable tunnels. It makes up for some shortcomings of traditional manual inspection and cable tunnel monitoring systems. This application conducts a relatively detailed study on the cable tunnel inspection robot, including the cable tunnel monitoring system, including the calculation of the inspection blind area of ​​the inspection robot, and also includes the communication and positioning of the cable tunnel inspection robot. The specific positioning method is discussed in detail in this application, and the kinematic simulation and analysis of the inspection robot are carried out using relevant application software.

[0063] 1. Trackless inspection and tracked inspection

[0064] The trackless inspection robot of the prior art is restricted by ground conditions and has a limited range of activities. In addition, since some sections inside the tunnel are stepped, the robot's obstacle-crossing ability is very high. At the same time, once a storm occurs, a large amount of water will accumulate inside the tunnel, which will seriously affect the normal operation of the robot. At the same time, the inspection blind spot problem needs to be considered during the detection process. Due to space limitations, the inspection robot has a large inspection blind spot. In addition, due to the large number of cables in the cable tunnel, it is inevitable that interference will occur to the cable tunnel, so the communication problem is a major difficulty. Although the use of a track-type inspection robot increases the cost, it can improve the inspection effect of the inspection robot and can repeatedly inspect the cable tunnel. There is no need to consider the inspection robot's obstacle crossing and other issues like ground mobile robots. Since the use of a track-type inspection robot can greatly improve the inspection efficiency of cables in cable tunnels, the present application uses a track-type inspection robot to inspect cable tunnels.

[0065] Therefore, the use of track-type inspection robots has greater advantages and meets the current requirements for comprehensive, all-weather, and efficient inspections of cable tunnels. Therefore, this application uses a track-type inspection robot, which also faces some key design issues and principles. First, the designed track must be suitable for the specific cable tunnel structure and its relevant national standards. At the same time, the cable tunnel inspection robot must have a certain climbing ability. In addition, due to the high humidity in the cable tunnel, the cable tunnel inspection robot must have a certain waterproof performance. At the same time, due to the large number of cables in the cable tunnel, there is strong electromagnetic interference, which will have a certain impact on the communication of the cable tunnel inspection robot. Therefore, the cable tunnel inspection robot must use high-reliability wireless communication means to achieve communication in the cable tunnel.

[0066] 2. Improvements based on obstacle crossing inspection robots

[0067] The cable tunnel inspection robot is improved on the basis of the obstacle crossing robot, and includes the following parts: clamping wheel, clamping joint, moving joint, walking wheel, slewing joint, chassis, and realizes the following movements: the rolling of the walking wheel makes the robot roll relative to the bottom line and travel along the steel pipe track. Since the working environment is located in the cable tunnel and cable trench, the internal environment is very harsh, there are many uncontrollable factors, and there are also many factors that need to be considered. Water seepage may occur inside the cable tunnel, so the robot must have a certain water release performance, increase the inspection arm, and carry various sensors at the end of the inspection arm, including temperature and humidity sensors and combustible gas sensors. In addition, it is also equipped with a visible light camera to identify the surface defects of the cable; the robot's driving path and its obstacle crossing characteristics are: the hanging hanging plate and its upper lifting wire clamp that block the robot from passing are designed and transformed into a lower lifting C-type structure hanging plate and lower lifting wire clamp that the robot can roll through, and the ground wire tension tower head that the robot cannot directly pass through is added with a rolling bridge at both ends, and a robot approach detection structure and a charging docking structure are added to the bottom of the lower lifting C-type hanging plate. For the anti-vibration hammer, parallel groove wire clamp, hanging and tension, the robot uses a rolling method to pass through all obstacles on the ground wire. This driving path design creates the necessary conditions for realizing unmanned monitoring and fully autonomous inspection of robots.

[0068] 3. Overhead Track Structure Scheme

[0069] All cables are placed on cable supports, with optical cables placed on the top layer, which do not require inspection. Steel pipe tracks are erected on the upper part of the tunnel and supported by brackets, one end of which is connected to the top of the tunnel. The length of the steel pipe track is not less than 500 meters. Since cables on the upper layers are more prone to local temperature rise, they need to be inspected intensively, so the track is located at the upper end of the cable tunnel. It is planned to use an overhead steel pipe track as the robot's walking path, with barrier-free pin connections between steel pipe track sections, and brackets installed on the top of the tunnel at intervals. The brackets are connected to the connecting pins between sections to form a barrier-free structure for the robot's rolling travel. The size of the overhead steel pipe track is determined according to the specific cable tunnel-related construction standards.

[0070] 4. Intelligent Robot Inspection Solution

[0071] The minimum passage space inside the cable trench is 450mm, the minimum height is 1200mm, and the upper layer and its top space are large enough to meet the work space for the inspection robot to pass overhead and conduct inspections. Therefore, this application adopts an overhead track inspection robot solution. The inspection robot as a whole includes the following parts: a walking mechanism, a clamping mechanism, a rotating mechanism, a control box, an inspection arm and an end detector, and the inspection robot performs inspections on a steel pipe track, and the track is erected on the top of the cable tunnel.

[0072] like Figure 1There are three inspection modes for the inspection robot: regular inspection, fixed-point inspection and emergency inspection. During regular inspection, the inspection robot walks while the detection arm reciprocates within the α angle range. Assume that the linear speed of the mobile robot is v, the angular velocity of the reciprocating rotation of the detection operation is ±ω, the field of view of the camera on the inspection arm on the horizontal plane is θ, and the width of the tunnel is L. In the regular inspection operation mode, the motion trajectory of the two end points of the detection arm (i.e., the origin of the camera human coordinate system) is a cycloid, and the pitch of the cycloid is the distance to be inspected by the detection arm in one reciprocating cycle and all the targets it contains. At this time, the detection equipment carried by the two arms detects the cables and environmental conditions on both sides respectively.

[0073] like Figure 2 and Figure 3 , the shaded part is the field of view of the camera carried by the inspection arm, and d is the distance the robot moves when the inspection arm rotates from top to bottom once, so that the field of view reaches all the targets in the tunnel, and the following relationship is obtained:

[0074]

[0075] The relationship between θ, v, and ω is determined by the above formula;

[0076] Conventional inspection is the main inspection method. In order to achieve full coverage of the field of view of the infrared thermal imager or visible light camera during the robot inspection process, the inspection speed of the inspection robot must have a critical value. When the inspection speed of the inspection robot exceeds this critical value, the field of view of the camera cannot achieve full coverage of the cables to be inspected in the cable tunnel. At this time, an inspection blind spot will be generated. Since the inspection area has a certain inspection height, if the swing angle of the inspection arm of the inspection robot is too small during the reciprocating swing process, the inspection cannot cover the entire range of the inspection area. Therefore, there are certain restrictions on the speed of the inspection robot and the rotation angle of the working arm.

[0077] like Figure 4 As shown, h i The cable area to be inspected. The top layer inside the cable tunnel is generally equipped with optical cables. The top layer does not need to be inspected. The area to be inspected is from the second layer to the bottom layer. i The width of the cable tunnel that needs to be inspected must meet full coverage within the vertical inspection range:

[0078]

[0079] Where ly1 is the vertical length between a point at the end of the inspection arm of the inspection robot and the center of the inspection area to be inspected, and ly2 is the vertical length between a point at the end of the working arm of the inspection robot and the highest point of the inspection cable area;

[0080] At the same time, it must be satisfied that within one inspection cycle of the robot, the distance the robot travels is less than or equal to the length of the field of view, that is:

[0081] S=vT≤l x Formula 4

[0082]

[0083] Where S is the distance the robot travels when the patrol arm completes one cycle, V is the robot's walking speed, T is one patrol cycle, that is, the time it takes for the patrol arm to complete one cycle, and α is the rotation angle of the patrol arm.

[0084] α and β are the horizontal and vertical field of view angles of the camera, respectively. Combining equations 3 and 4, we can get:

[0085]

[0086] Among them l a is the length of the inspection arm. Substituting equations 7 and 8 into equation 3, we can obtain the critical condition of the rotation angle:

[0087]

[0088] Combining the above formula, we can get the critical speed condition:

[0089]

[0090] The critical condition of the robot's driving speed is obtained from formula 10, that is, the robot's walking speed cannot exceed the critical value. Once the inspection robot's walking speed exceeds the critical value, the camera's field of view will not be able to fully cover the cable inspection area, and a blind inspection area will be generated. Therefore, in order to avoid the occurrence of a blind inspection area, the robot's driving speed cannot exceed the critical value. This critical value can be calculated by formula 10.

[0091] The critical value of the rotation angle of the inspection arm is obtained by formula 9, that is, the rotation angle of the inspection arm must exceed a certain value, at which time the field of view of the camera can completely cover the entire height of the cable area to be inspected. If the rotation angle of the inspection arm is less than this specific value, the field of view of the camera cannot cover the entire cable area to be inspected, and an inspection blind spot will be generated. Therefore, the rotation angle of the inspection arm must exceed a certain value, and this specific value is calculated by formula 9.

[0092] In addition, the inspection robot can also perform fixed-point inspections, that is, the inspection robot stops walking, and the detection arm reciprocates within the α angle range, and the trajectory of its two end points is an arc. This method realizes the fine inspection of the specified section or target object, which is suitable for key parts or suspected fault troubleshooting;

[0093] Emergency inspection is that the mobile robot quickly reaches the designated part and then conducts a special inspection on it. No inspection is performed during the rapid arrival process. Special inspections include sound detection of water seepage and corona, and detection of smoke and toxic gases. This inspection method is suitable for robots that have moved away from the designated area for emergency inspection. In these two inspection modes, the visible light and infrared equipment carried by the arms detect the same side, and the two sides are performed successively.

[0094] The inspection robot travels along the overhead steel pipe track. The robot uses two walking wheels to drive the rolling movement. The steel pipe track is supported by a bracket. The steel pipe sections are connected by internal pin shafts. The bracket and its internal connection structure between sections are designed appropriately so that the bracket and its internal connection structure do not constitute obstacles for the rolling movement of the walking wheels. The robot can continuously roll to any position on the track or tunnel. For the curved track, the rules for the robot to travel on the curved track are as follows: Figure 5 .

[0095] The mobile robot platform is a mobile robot with two wheel-arm composites and arms with limited rotation pairs around a vertical axis. Specifically, each arm is suspended by a walking wheel, and the two walking wheels are independently driven to roll. Each arm has a kinematic pair with limited rotation around a vertical axis. When the two rotation pairs are locked, the two mechanical arms are fixed to the frame to achieve walking along a straight track. When the rotation pairs of the two arms are in a non-locked state, turning walking on tracks with different curve radii can be achieved. When encountering a curve, the rotary axis is in a non-locked, under-driven free state, and passes through the curve at a low speed. The forward direction of the wheel is driven by the track. When the robot walks on a straight section, both arms are locked, that is, in a non-free moving state.

[0096] 5. Fire Door Renovation Plan

[0097] When the cable tunnel inspection robot conducts routine inspections of the cable tunnel, some special situations may occur. For example, a fire suddenly occurs in the cable tunnel. At this time, the fire doors related to the cable tunnel will be closed. At this time, the inspection robot will not be able to reach the designated area through the fire doors. Therefore, if an overhead track structure is used, the fire doors inside the cable tunnel need to be modified.

[0098] After the fire door is modified, when the inspection robot inspects the cable tunnel, when the inspection robot inspects near the fire door, it stops and sends information to the cable monitoring system. At this time, the cable monitoring system determines whether the fire door is open. If the fire door is not open, the fire door is opened, and the inspection robot can pass smoothly. If the cable tunnel inspection robot can have a high inspection efficiency for the cable tunnel, the fire door will not be closed suddenly. Only in extremely special circumstances will the fire door be closed. When the cables in the cable tunnel are normal, the fire door will not be closed. The discussion at this time is possible only in extremely special circumstances. After the cable tunnel fire door is modified, even if a sudden danger occurs, the robot can pass through smoothly and reach the designated area. In short, in order to ensure that the inspection robot can safely reach the designated area in certain special circumstances, it is very necessary to improve the tunnel fire door to a certain extent. Although this increases the cost to a certain extent, it improves the inspection efficiency of the inspection robot for the cable tunnel and can maximize the feasibility of the inspection. At the same time, the adaptability of the inspection robot to complex situations is improved, so it is necessary to transform the tunnel fire doors.

[0099] After the tunnel fire door is modified, the robot can smoothly pass through the fire door to reach the designated area to perform corresponding work.

[0100] 6. Inspection Robot Communication and Positioning

[0101] During the inspection process, the inspection robot uses wireless communication, such as Figure 6 Wired optical cable communication is used between the cable tunnel and the ground monitoring room, and multiple 5G wireless network communications are used between the inspection robot and the optical cable. The robot and multiple wireless network nodes on the optical cable dynamically establish point-to-point communication, that is, the robot automatically searches for network node signals, and automatically selects the one with the strongest signal strength among the searched network nodes as its current communication network. When the signal strengths of two nodes are equal, the robot's positioning is used to determine the one with the closest distance to the node. The number and distance of network nodes are determined according to the cable tunnel and the communication module selected.

[0102] The optical fiber signal is connected to the monitoring room, demodulated by the access device and sent to the computer (downlink), or transmitted by the computer to the robot (uplink) through the access device. The data is bidirectional and the image is only unidirectional downward. Under the system management, the entire monitoring system completes the remote control operation of the robot, infrared and visible light diagnosis, combustible gas data analysis, other data analysis, and automatic update of the database in parallel. Among them, autonomous control refers to the autonomous patrol control of the inspection robot, which is loaded in the inspection robot, while the autonomous control in the monitoring system requires the modification of the autonomous control parameters of the inspection robot, or the reconfiguration of the autonomous control software for different cable tunnels.

[0103] The database refers to the database established for cable tunnels, inspection images and data, analysis and diagnosis results, and fault handling, and the cable tunnel data sub-database also serves as the inspection positioning and control database for the inspection robot.

[0104] The inspection robot uses RFID wireless radio frequency short-range communication to identify specific targets and read and write relevant data through radio signals. Its advantages are that it does not require optical or mechanical contact, and reading and writing can be fully automatic without manual work. It can also work stably in harsh environments, and is more suitable for underground cables and cable trenches. The cost is extremely low. By setting relevant tags on the bracket, the robot can know its location by reading the relevant tags.

[0105] 7. Inspection Robot Detection System

[0106] The robot is equipped with relevant sensors at the end of the inspection arm. Since the cables inside the cable tunnel are prone to local temperature rise, and since shield tunnels and jacking tunnels are prone to water seepage inside the tunnel, the cable tunnel autonomous inspection robot needs to be equipped with a temperature and humidity sensor at the end of its inspection arm. In addition, due to the large number of cables inside the cable tunnel, some toxic and harmful gases or flammable gases may be generated during the operation of the cables. Therefore, a flammable gas sensor is configured at the end of the inspection arm of the cable tunnel autonomous patrol robot. According to its detection principle, flammable gases are divided into four categories: thermal conductivity, contact combustion, semiconductor, and infrared absorption. The most commonly used is the catalytic combustion type of flammable gas sensor. The catalytic combustion method is to detect the content of flammable gas in the internal environment of the cable tunnel through catalytic combustion until the flammable gas content in the ambient air inside the cable tunnel reaches the lowest explosion concentration. The detection element is a Pt wire coil wrapped with aluminum oxide and a binder to finally become a sphere, which can be finally obtained by sintering. Its outer layer is a platinum metal catalyst, which is a black element. Its schematic diagram is as follows Figure 7Otherwise, its outer surface is not coated with Pt or Pb metal catalyst, and is a white element. The black and white elements with similar resistance values ​​cooperate with each other and form a Wheatstone bridge together with the compensation resistor.

[0107] During the detection process of combustible gas, a combustion reaction occurs on the surface of the sensitive element, releasing heat, causing the temperature of the sensitive element to continue to rise. The sensitive element is formed by a spiral cypress and a catalytic carrier material adhered to the surface. The cypress is a material that is very sensitive to temperature. If the temperature of the sensor begins to rise, its resistance value increases R, and the bridge has an unbalanced voltage V, which reflects the volume fraction of the combustible gas. The detected combustible gas concentration value is the comprehensive value of the concentration of various combustible gases in the air of the cable tunnel. At the same time, this combustion reaction is a reaction that must have the participation of oxygen, and the oxygen content in the air detected in the cable tunnel cannot be too low.

[0108] Since cable tunnels are somewhat different from overhead transmission lines in that there are a large number of cables in cable tunnels, it is more likely that local temperature rise will occur in the cables. Traditional cable tunnel monitoring systems have certain inspection blind spots, so the inspection robot must include the measurement of the temperature near the cables inside the cable tunnel. At the same time, since a certain degree of humidity may be generated inside the cable tunnel, it is necessary to detect the humidity inside the environment. Therefore, temperature and humidity sensors are also used to detect changes in cable temperature. Non-contact temperature sensors are used to measure temperature changes around the cables, and there is no limit on the upper limit of the maximum measurable temperature.

[0109] In addition, an infrared thermal imager is installed at the end of the inspection arm, which moves on a pan-tilt platform with two degrees of freedom: 360-degree rotation and 90-degree pitch. The combined effect of the rotation of the working arm (the end motion trajectory), the pan-tilt platform movement and the imager's pyramid-shaped effective optical field of view is detected to achieve full coverage inspection of the cable tunnel.

[0110] 8. Kinematics simulation and analysis of inspection robot

[0111] The kinematic simulation of the inspection robot is carried out using the motion module in SolidWorks. The three-dimensional model is simplified for kinematic simulation, and the inspection process of the robot is simulated. Before the simulation, the relevant parameters are set first.

[0112] Perform motion simulation on the routine inspection process of the inspection robot. Before performing motion simulation, set the parameters first, first of all, set the gravity parameters, set the direction to the negative direction of the Y axis, and use the default value.

[0113] At the same time, entity contact is set, contact groups are used, and materials are used as follows Figure 8 Materials shown, other parameters use default values.

[0114] Then add the corresponding motors, add linear motors and rotary motors at the corresponding positions. Because it is inside the cable tunnel, the outside of the cable tunnel needs to be set to transparent. The above is the motion simulation of the routine inspection process of the inspection robot.

[0115] Since the rotary motor applied above adopts a constant speed, the vertical displacement and angular velocity of the swing arm are obtained. Since the linear motor applied is at a constant speed, the speed curve of the walking wheel is a straight line. In order to achieve full coverage of the camera field of view, the angular velocity of the robot's slewing arm should not be set too low to avoid blind inspection areas.

[0116] In addition, through the analysis of the simulation results, it can be seen that the walking speed of the inspection robot should not be too high, otherwise there will still be visual blind spots, resulting in the inspection being unable to achieve full coverage of the cable area to be inspected. Therefore, the driving speed of the inspection robot should not exceed a critical value to achieve full coverage of the cable area to be inspected.

[0117] This application uses SolidWorks motion to perform kinematic simulation of the inspection robot and obtains the relationship between important parameters. It is finally found that the walking speed of the inspection robot and the angular velocity of the inspection arm need to meet certain conditions to avoid inspection blind spots.

Claims

1. An intelligent monitoring robot for underground cable tunnel power inspection, characterized in that: The track of the rail-type inspection robot is set up on the top of the cable tunnel. The inspection robot is based on the improvement of the obstacle-crossing inspection robot. The inspection modes are divided into three types: conventional inspection, fixed-point inspection and emergency inspection. An intelligent robot inspection plan is established, and the inspection blind spots are eliminated by calculation. The tunnel fire doors are modified. At the same time, methods for the inspection robot to pass through straight segments and curves are constructed respectively. The positioning and communication solutions of the inspection robot are established. Infrared thermal imagers, visible light cameras and various sensors are installed at the end of the inspection arm. The kinematic simulation of the inspection robot is carried out to obtain the relationship between important parameters, determine the conditions that the walking speed of the inspection robot and the angular velocity of the inspection arm need to meet, and avoid the occurrence of inspection blind spots. 1) Construct a rail-type cable tunnel inspection robot, which is improved on the basis of the original obstacle-crossing inspection robot, and establish the mechanical structure of the robot body and the track respectively, including the walking mechanism, the rotating mechanism, the clamping mechanism, the control box, the inspection working arm and the terminal detector. The terminal detection instrument includes a temperature and humidity sensor, a combustible gas sensor, an infrared thermal imager, an ultrasonic sensor, and is equipped with an infrared thermal imager and a pan-tilt camera; 2) Establish the mobile positioning and communication method of the inspection robot, use RFID wireless radio frequency technology for positioning, set up an infinite bridge at intervals in the cable tunnel to solve the communication problem of the inspection robot, and eliminate the inspection blind spots in the process of the robot inspecting the cable tunnel by calculating the inspection blind spots. Establish the obstacle-passing method of the inspection robot and transform the tunnel fire door; 3) Establish a three-dimensional model of the inspection robot and a cable tunnel model, and use SolidWorks motion to perform kinematic simulation and analysis on the robot to specifically express the robot inspection process.

2. According to claim 1, the underground cable tunnel power inspection intelligent monitoring track robot is characterized in that: Improvement of the inspection robot based on crossing obstacles: The cable tunnel inspection robot is improved on the basis of the crossing obstacle robot, including the following parts: clamping wheel, clamping joint, moving joint, walking wheel, slewing joint, chassis, and realizes the following movements: the rolling of the walking wheel makes the robot roll relative to the bottom line, travels along the steel pipe track, adds an inspection arm, and carries various sensors at the end of the inspection arm, including temperature and humidity sensors and combustible gas sensors. In addition, it is also equipped with a visible light camera to identify the surface defects of the cable; the robot's driving path and its obstacle crossing characteristics are: the hanging hanging plate and the upper lifting wire clamp that block the robot from passing are respectively designed and transformed into the lower lifting C-type structure hanging plate and the lower lifting wire clamp that the robot rolls through, and the ground wire tension tower head that the robot cannot pass directly is added with a rolling bridge at both ends, and the robot proximity detection structure and charging docking structure are added on the bottom of the lower lifting C-type hanging plate. For the anti-vibration hammer, parallel groove wire clamp, hanging and tension, the robot adopts the rolling method to pass through all obstacles on the ground wire.

3. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 1 is characterized in that: Overhead track structure plan: All cables are placed on cable supports, and optical cables are placed on the top layer. No inspection is required. The steel tube track is erected on the upper part of the tunnel and supported by a bracket. One end of the bracket is connected to the top of the tunnel. The length of the steel tube track is not less than 500 meters, and the track is located at the upper end of the cable tunnel. It is planned to use an overhead steel tube track as the robot's walking path. The steel tube track sections are connected by barrier-free pins, and each section is supported by a bracket installed on the top of the tunnel. The bracket is connected to the connecting pins between sections to form a barrier-free structure for the robot to roll. The size of the overhead steel tube track is determined according to the specific cable tunnel-related construction standards.

4. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 1 is characterized in that: Intelligent robot inspection solution: The overhead rail inspection robot solution is adopted. The inspection robot generally includes the following parts: Walking mechanism, clamping mechanism, slewing mechanism, control box, inspection arm and terminal detector, and the inspection robot performs inspection on the steel pipe track, which is set on the top of the cable tunnel; The inspection robot has three inspection modes: regular inspection, fixed-point inspection and emergency inspection. During regular inspection, the inspection robot walks while the detection arm reciprocates within the α angle range. Assume that the linear speed of the mobile robot is v, the angular speed of the detection reciprocating rotation is ±ω, the field of view of the camera on the inspection arm on the horizontal plane is θ, and the width of the tunnel is L. In the regular inspection mode, the motion trajectory of the two end points of the detection arm is a cycloid, and the pitch of the cycloid is the distance to be inspected by the detection arm in one reciprocating cycle and all the targets it contains. At this time, the detection equipment carried by the two arms detects the cables and environmental conditions on both sides respectively. d is the distance the robot moves when the inspection arm rotates from top to bottom once, so that the field of view reaches all the targets in the tunnel, and the following relationship is obtained: The relationship among θ, v, and ω is determined by the above formula.

5. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 4 is characterized in that: Conventional inspection is the main inspection method. In order to achieve full coverage of the field of view of the infrared thermal imager or visible light camera during the robot inspection process, the inspection speed of the inspection robot must have a critical value. When the inspection speed of the inspection robot exceeds this critical value, the field of view of the camera cannot achieve full coverage of the cables to be inspected in the cable tunnel, and an inspection blind spot will be generated. There are certain restrictions on the speed of the inspection robot and the rotation angle of the working arm. h i The cable area to be inspected. The top layer inside the cable tunnel is generally equipped with optical cables. The top layer does not need to be inspected. The area to be inspected is from the second layer to the bottom layer. i The width of the cable tunnel that needs to be inspected must meet full coverage within the vertical inspection range: Among them l y1 is the vertical length between the end of the inspection arm of the inspection robot and the center of the inspection area to be inspected, l y2 It is the vertical length between the end point of the inspection robot's working arm and the highest point of the inspection cable area; At the same time, it must be satisfied that within one inspection cycle of the robot, the distance the robot travels is less than or equal to the length of the field of view, that is: S=vT≤lx Formula 4 Where S is the distance the robot travels when the patrol arm completes one cycle, V is the robot's walking speed, T is one patrol cycle, that is, the time it takes for the patrol arm to complete one cycle, and α is the rotation angle of the patrol arm; α and β are the horizontal and vertical field of view angles of the camera, respectively. Combining equations 3 and 4, we can get: Among them l a is the length of the inspection arm. Substituting equations 7 and 8 into equation 3, we can obtain the critical condition of the rotation angle: Combining the above formula, we can get the critical speed condition: The critical condition of the robot's driving speed is obtained from Formula 10, that is, the robot's walking speed cannot exceed the critical value. Once the inspection robot's walking speed exceeds the critical value, the camera's field of view will not be able to fully cover the cable inspection area, and an inspection blind spot will be created. Therefore, the robot's driving speed cannot exceed the critical value, which can be calculated by Formula 10.

6. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 4 is characterized by: The inspection robot can also perform fixed-point inspection, that is, the inspection robot stops walking, and the detection working arm rotates back and forth within the α angle range. The trajectory of its two end points is an arc. This method can achieve detailed inspection of specified sections or targets, which is suitable for key areas or suspected fault troubleshooting.

7. The underground cable tunnel power inspection intelligent monitoring tracked robot according to claim 4 is characterized by: Emergency inspection is that the mobile robot quickly reaches the designated location and then conducts special inspections. No inspection is performed during the rapid arrival process. Special inspections include water seepage and corona sound detection, smoke and toxic gas detection. This inspection method is suitable for robots that have moved away from the designated area for emergency inspection. The visible light and infrared equipment carried by the two arms detect the same side, and the two sides are inspected one after another. The inspection robot travels along the overhead steel pipe track. The robot is driven by two running wheels. The steel pipe track is supported by a bracket. The steel pipe sections are connected by internal pins. The bracket and its internal connection structure between sections are designed appropriately so that the bracket and its internal connection structure do not constitute obstacles to the rolling of the running wheels. The robot can continuously roll to any position on the track or tunnel. The mobile robot platform is a mobile robot with two wheel-arm composites and arms with limited rotation pairs around a vertical axis. Specifically, each arm is suspended by a walking wheel, and the two walking wheels are independently driven to roll. Each arm has a kinematic pair with limited rotation around a vertical axis. When the two rotation pairs are locked, the two mechanical arms are fixed to the frame to achieve walking along a straight track. When the rotation pairs of the two arms are in a non-locked state, turning walking on tracks with different curve radii can be achieved. When encountering a curve, the rotary axis is in a non-locked, under-driven free state, and passes through the curve at a low speed. The forward direction of the wheel is driven by the track. When the robot walks on a straight section, both arms are locked, that is, in a non-free moving state.

8. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 1 is characterized in that: Fire door renovation plan: After the fire door is renovated, when the inspection robot inspects the cable tunnel, when it inspects near the fire door, it stops and sends information to the cable monitoring system. At this time, the cable monitoring system determines whether the fire door is open. If the fire door is not open, the fire door is opened, and the inspection robot can pass smoothly. If the cable tunnel inspection robot can have a high inspection efficiency in the cable tunnel, the fire door will not be closed suddenly; the fire door will only be closed under extremely special circumstances. At this time, after the cable tunnel fire door is modified, even if a sudden danger occurs, the robot can pass through smoothly and reach the designated area.

9. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 1, characterized in that: Inspection robot communication and positioning: During the inspection process, the inspection robot uses wireless communication, and uses wired optical cable communication between the cable tunnel and the ground monitoring room. Multiple 5G wireless network communications are used between the inspection robot and the optical cable. The robot and multiple wireless network nodes on the optical cable dynamically establish point-to-point communication, that is, the robot automatically searches for network node signals, and automatically selects the one with the strongest signal strength among the searched network nodes as its current communication network. When the signal strengths of two nodes are equal, the robot's positioning is used to determine the one with the closest distance between the robot and the node. The number and distance of network nodes are determined based on the cable tunnel and the selected communication module; The optical fiber signal is connected to the monitoring room, demodulated and sent to the computer through the access device, or transmitted from the computer to the robot through the access device. The data is bidirectional and the image is only one-way downward. Under the system management, the entire monitoring system completes the remote control operation of the robot, infrared and visible light diagnosis, combustible gas data analysis, other data analysis, and automatic update of the database in parallel. Among them, autonomous control refers to the autonomous patrol control of the inspection robot, which is loaded in the inspection robot, while the autonomous control in the monitoring system requires the modification of the autonomous control parameters of the inspection robot, or the reconfiguration of the autonomous control software for different cable tunnels.

10. The underground cable tunnel power inspection intelligent monitoring track robot according to claim 1, characterized in that: Kinematics simulation and analysis of inspection robots: Kinematics simulation of inspection robots is carried out by using the motion module in SolidWorks. The 3D model is simplified for kinematics simulation and the inspection process of the robot is simulated. Before simulation, relevant parameters are set. First, set the gravity parameters. Set the direction to the negative direction of the Y axis. Use the default values. Set the entity contact and use the contact group. Use the default values ​​for other parameters. Then add the corresponding motors. Add linear motors and rotary motors at the corresponding positions. The rotating motor used in the above application is of constant speed, the speed curve of the walking wheel is a straight line, and the angular speed of the robot's rotating arm should not be set too low to achieve full coverage of the camera's field of view to avoid blind inspection areas; In addition, the walking speed of the inspection robot should not be too high, otherwise there will still be visual blind spots. The driving speed of the inspection robot should not exceed a critical value to achieve full coverage inspection of the cable area to be inspected.

Images