Permanent Magnet Adsorption Research Articles

Analysis and Simulation of Permanent Magnet Adsorption Performance of Wall-Climbing Robot

In response to problems such as insufficient adhesion, difficulty in adjustment, and weak obstacle-crossing capabilities in traditional robots, an innovative design has been developed for a five-wheeled climbing robot equipped with a pendulum-style magnetic control adsorption module. This design effectively reduces the weight of the robot, and sensors on the magnetic adsorption module enable real-time monitoring of magnetic force. Intelligent control adjusts the pendulum angle to modify the magnetic force according to different wall conditions. The magnetic adsorption module, using a Halbach array, enhances the concentration effect of the magnetic field, ensuring excellent performance in high-load tasks such as building maintenance, bridge inspection, and ship cleaning. The five-wheel structural design enhances the stability and obstacle-crossing capability, making it suitable for all-terrain environments. Simulation experiments using Maxwell analyzed the effects of the magnetic gap and the angle between the adsorption module and the wall, and mechanical performance analysis confirmed the robot’s ability to adhere safely and operate stably.

A wall climbing robot based on machine vision for automatic welding seam inspection

With the ongoing progress of industrial technology such as shipbuilding, the importance of weld quality in industrial production is becoming increasingly prominent. Intelligent and automated welding seam inspection robots are more efficient than traditional manual inspection and can avoid dangerous accidents. This article describes the design of a welding seam inspection robot suitable for high-altitude ship operation. The robot uses machine vision and object segmentation models to automatically detect the position of welding seams, and uses a cubic polynomial to fit the welding seam path. The upper and lower computers of the robot communicate through WIFI transmission and TCP protocol, which can realize remote real-time detection of weld surface defects. In addition, this article designs a permanent magnet adsorption structure for robot high-altitude wall climbing, which has been verified through simulation and experimental verification. To verify the intelligence of the robot, this paper conducted performance analysis experiments on weld line recognition and tracking models and surface defect models. The experimental results showed that the average detection accuracy of the weld line recognition and tracking algorithm was 96.8%, and the average detection accuracy of surface defects in the three types of welds was 94.2%. The method proposed in this article combines two algorithms and a special robot structure, providing a new approach for the automated inspection of welds in large industrial products such as ships.

Development of Portable Magnetic Adsorption Amphibious Robot

In this study, a portable magnetic adsorption amphibious robot which can operate on and below the waterline is developed for special curved environments, such as the pile legs of offshore platforms and the outer walls of ships. An open robot integrated control system based on a domestic chip is developed, and two operating modes of local control operation and remote wireless operation are realized. A permanent magnet adsorption scheme combining a magnetic adsorption track and a synchronous belt wheel is designed, static and dynamic analysis of the wall-climbing operation of the robot is carried out, and a kinematic model of the underwater robot is established. The experimental results show that the robot can effectively complete amphibious tasks and can realize the accurate control of attitude in water, proving it to be an effective tool for amphibious tasks, such as operating on the pile legs of offshore platforms and the outer walls of ships.

Design based on portable amphibious track robot

A portable amphibious robot that can operate on and under the waterline is designed for the special curved environment such as the pile leg of the offshore platform and the outer wall of the ship. The mechanical structure of the robot and the permanent magnet adsorption scheme of the magnetic adsorption track are designed. The robot can effectively complete amphibious tasks, and provides an effective way for amphibious tasks such as pile legs of offshore platforms and exterior walls of ships.

Design and analysis of a passive adaptive wall-climbing robot on variable curvature ship facades

To improve the adaptive motion performance of traditional wall-climbing robots on variable-curvature facades, a crawler-type wall-climbing robot suitable for ship wall features is proposed by utilizing the advantages of passive mechanisms in realizing autonomous robots. The robot consists of two passive adaptive crawler mechanisms and a connecting module. Each track structure contains multiple permanent magnets that can passively adapt to concave and convex facades of different curvatures. A static failure model is established according to the characteristics of the triangular distributed load, and the minimum adsorption force required for the robot to achieve safe motion is determined. The Halbach Array magnetic circuit design method was used to construct a gap-type permanent magnet adsorption model for lightweight design. The influence of wall thickness and air gap distance on the adsorption force is analyzed by parametric simulation. The prototype platform test shows that the robot can realize adaptive variable curvature motion through passive adjustment of the mobile mechanism attitude and has a certain load capacity.

Optimization Design and Parameter Analysis of a Wheel with Array Magnets

At present, a large number of magnetic wall-climbing robots are applied to various magnetically conductive metal facades for detection and anti-corrosion work. Limited by the wall-climbing mechanism and adsorption device, most wall-climbing robots can only climb on smooth walls, and it is difficult to adapt to complex walls. Therefore, by studying the multi-media magnetic circuit conduction mechanism, a permanent magnetic adsorption wheel with a magnet array arrangement was designed in this study and applied to a hinge-type wall-climbing robot. By analyzing the influence of structural parameters on the adsorption performance and optimization design, a magnetic wheel structure with a symmetric structure that can meet a variety of adsorption requirements was obtained. To analyze the mechanical characteristics of the wall-climbing robot under complex facade conditions, we researched the adsorption performance of the designed magnetic wheel in different wall structures. Finally, the adhesion force of the magnetic wheel was verified through experimental measurements, and it was found that the hinged wall-climbing robot could adapt to different structural features and complete wall-transition and obstacle-crossing movements.

Design and optimization of a permanent magnet crawler for a marine wall-cleaning robot

At present, ship wall cleaning is important in the marine engineering equipment maintenance industry. Designing permanent magnetic adsorption units is one of the most important ways to implement efficient, environmentally friendly, high-quality ship cleaning work. In this paper, theoretical design tests and technical studies are carried out on the permanent magnetic crawler structure of the ship cleaning and wall climbing robot, and the adsorption method, walking method, magnetic material and permanent magnetic adsorption structure of the ship cleaning and wall climbing robot are comprehensively analyzed and selected. Finally, the design of the permanent magnetic crawler for the ship cleaning and wall climbing robot is proposed.

Adsorption Structure Design of a Wall Climbing Robot for a Spherical Tank

The main body of the LPG (Liquefied Petroleum Gas) spherical tank is a spherical shell, which is a component to store materials and bear the working pressure of materials and the static pressure of the liquid column. Because most spherical tanks are pressure or cryogenic vessels, most materials are flammable and explosive, and the loading capacity is large. Once an accident occurs, the consequences will be unimaginable. Therefore, more and more companies and research institutes are now involved in the research of robots suitable for the operation of spherical tanks. Among them, the foundation and premise of the spherical tank climbing robot are stable and have reliable adsorption capacity. Based on in-depth investigation and research on the existing robot adsorption structure and considering its actual working conditions, this paper designed an adsorption technology based on the combination of permanent magnetic adsorption and electromagnetic adsorption, which mainly focuses on permanent magnetic adsorption and automatically adjusts the electromagnetic adsorption force according to the robot attitude. Thus, the robot has good adsorption and driving performance at any position on the ball wall.

Design and analysis of a climbing robot for weld detection

The climbing robot is gradually applied to the safety weld detection on large metal walls to avoid manual operation. However, most robots are difficult to perform efficient operations for the poor performance on obstacle overcoming, flexible turning and motion stability. This paper presents a weld detection climbing robot, which integrates contact permanent magnet adsorption units and crawler chain mobile mechanism to obtain continuous, flexible and stable motion performance on large metal walls. By establishing the robot mechanical model, the minimum adsorption force can be calculated considering the instability conditions such as sliding, longitudinal overturning and lateral overturning. Combined with the Ansys Maxwell simulation, the magnet structure was optimized to obtain the structural size of a single permanent magnet adsorption unit. Experimental results show the robot can achieve stable motion and accurate detection on large metal walls with welds, and the maximum load of the robot can reach to 15.6 kg, which meets the engineering application requirements of weld detection on large metal walls.

Automation Solution to Wall-climbing Robot Working for Large-scale Metal Spherical Tanks

The modern weld inspection by robot operation has been attractive for safe-guarding large-scale pressure equipment in chemical energy industry by avoiding hard labors in harmful and toxic environments, with lower costs and higher efficiency and especially without the need of complex scaffolding. A wall-climbing robot based on permanent magnet adsorption is introduced to perform weld inspections of large-scales metal spherical tanks. This paper expounds the mechanical structure, intelligent visual functionality and intelligent walking system of the designed robot. Its optimized walk paths are proposed. Numerous engineering tests indicate good performance of designed robot in achieving high-quality surface treatment and non-destructive testing for large-scales metal spherical tanks. The suggested scheme provides an automation solution to wall-climbing robots working for large-scale metal spherical tanks.

Design and analysis of a wall‐climbing robot for passive adaptive movement on variable‐curvature metal facades

AbstractTo facilitate the safe adsorption and stable motion of robots on curved metal surfaces, a wall‐climbing robot with a wheeled‐type mobile mechanism that can passively self‐adapt to walls with different curvature is proposed. The robot is composed of two relatively independent passive adaptive mobile mechanisms and overrunning permanent magnetic adsorption devices to achieve effective fitting of the driving wheels to the wall surface and adaptive surface motion. The overall design is based on a double‐hinged connection scheme and gap‐type permanent magnetic adsorption. The minimum adsorption force required for the robot to achieve stable climbing motion with no risk of slipping or capsizing is determined by developing a static analysis model. The effects of air‐gap size and wall thickness on the adsorption force are analyzed by means of magnetic circuit design studies and parametric simulations on the permanent magnet adsorption device, as well as design optimization of the permanent magnet device. The motion performance test of the fabricated prototype shows that the robot can achieve adaptive curvature motion with self‐attitude adjustment, and has a certain load capacity, obstacle crossing capability, and good surface adaptivity.

Magnetic Circuit Analysis of Halbach Array and Improvement of Permanent Magnetic Adsorption Device for Wall-Climbing Robot

To solve the problems that the theoretical analysis of Halbach array magnetic circuit is insufficient and that calculating the magnetic adsorption force of a permanent magnet by using the magnetic node method is complex, the magnetic flux density of a Halbach array magnetic circuit composed of multiple permanent magnets with perpendicular magnetization directions is calculated. On the basis of the concentrated magnetic phenomenon of the ferromagnetic material and the end effect of the permanent magnet, a method for calculating the magnetic adsorption force of the Halbach array magnetic circuit by using the equivalent magnetic flux density is proposed, and the variation trend of magnetic adsorption force after changing the parameters of the magnetic circuit is obtained. ANSYS software is used to analyze several magnetic circuits that produce large magnetic adsorption force, a magnetic circuit structure that produces the largest magnetic adsorption force is determined, and the permanent magnetic adsorption device of the wall-climbing robot is improved. The magnetic adsorption force of the wall-climbing robot before and after the improvement of the permanent magnetic adsorption device is measured through experiments. The experimental results show that the magnetic adsorption force after the improvement is increased by 24.63% compared to before the improvement.

Analysis and improvement of non-contact permanent magnet adsorption unit for ship wall-climbing robot

In order to ensure the stable operation of the wall-climbing robot on the ship's complex curved wall surface, analysis and optimisation method of non-contact permanent magnet adsorption unit is discussed in this paper. The influence of magnet arrangement, coupling, air gap distance and other factors on the adsorption force is analysed by finite element simulation software, and the parameter magnet-to-mass ratio is introduced to quantitatively compare these schemes. In the two scenarios of planar wall and curvature-varying wall, the structural parameters of the Halbach array are optimised with the maximum magnetic-to-mass ratio as the optimisation objective, and the ratio of adsorption force variation is proposed as the reference of design to ensure the performance of the adsorption unit on the variable-curvature wall. The running stability of the wall-climbing robot with designed magnetic adsorption unit is verified by experiments on the wall with varying curvature.

Analysis and Improvement of Non-contact Permanent Magnet Adsorption Unit for Ship Wall-climbing Robot

Analysis and Improvement of Non-contact Permanent Magnet Adsorption Unit for Ship Wall-climbing Robot

Development of a new type of automatic magnetic particle inspection wall-climbing robot

In the paper, a permanent magnet adsorption wall-climbing robot using magnetic particle detection technology for crack detection is introduced, which solves the problems of low efficiency of traditional manual detection and long detection time. According to the working environment of the detection system and the detection functions that need to be completed, the body structure of the robot is designed, the overall size of the robot is smaller than the distance between two steam turbine blades, so it can achieve the crack detection function of large steam turbine blades, and the stability and force analysis of the robot are carried out, and the adsorption conditions that meet the conditions of no sliding and overturning are obtained. In the paper, we use the magnetic circuit method to design a miniature excitation device for robotic applications and use the simulation software Ansoft-Maxwell to verify its feasibility. In the final experiment, it can be shown that the robot designed can achieve a series of functions such as magnetic particle inspection and image acquisition. There is a good prospect for the inspection of turbine blades.

A novel field box girder welding robot and realization of all-position welding process based on visual servoing

Abstract Box-type steel structure has been widely applied in the field of buildings and bridges because of its unique advantages. However, there are still many problems in field welding that need to be solved. In order to improve the level of automation and intellectualization in field welding of box girder, a new type of on-site all-position welding robot system is developed and designed in this paper. The convenience of on-site installation and debugging of the robot is realized by the scheme of permanent magnet adsorption and straight-arc combined track. The motion matching scheme of bilateral wheel-axle clamping makes the circumferential movement of the robot much smoother and more stable which makes the system with better overall force characteristics and load-carrying capacity. Then, a novel visual sensor based on combined laser structured lights is proposed and designed, which can realize several functions such as groove parameters detection, welding joint tracking and torch posture detection in field welding based on single detection image, so as to effectively improve the flexibility and intelligence of field welding robot. After that, based on the designed visual sensor and welding robot system, a visual servo-control system based on Visual Studio platform is established. Through the effective integration of detection image reading, image processing and calculation, image feature parameters transmission, motion control board call and feedback control signal output, the adjustment and control of welding torch's position and posture based on visual servo-control are realized. Furthermore, based on the kinematics calculation and the welding process requirements of the box girder, the welding process design is planned for the all-position welding of the box steel girder, which solved the technical problem of the rectangular fillet welding in the box steel butt welding (the welding torch position and posture transition control in right-angled corner of girth butt joint). Finally, all-position welding experiments of box steel girder were carried out. The results show that the welding robot based on visual servo-control can realize better control of weld formation in all-position welding of box steel girder.

Design and adsorption force optimization analysis of TOFD-based weld inspection robot

To meet the requirements of large metal tank weld inspection, a robot design scheme was proposed to walk on the outer surface of the tank and carry TOFD probe. The wall-climbing module, connecting frame module and TOFD weld inspection module are specifically designed. In this paper, the permanent magnetic adsorption principle and four-wheeled mechanism are both adopted in the wall-climbing module, meanwhile, the magnetic wheel’s adsorption force is analyzed under multiple parameters. The main parameters affecting the adsorption force are obtained. To ensure the minimum size and the lightest quality of magnetic wheel, the adsorption force is also optimized based on the main parameters which are related to the permanent magnet itself. The above work provides a reference value for the research and development of intelligent weld inspection products of large metal tanks.

Design of novel multidirectional magnetized permanent magnetic adsorption device for wall-climbing robots

A multidirectional magnetized permanent magnetic adsorption device (PMAD) for wall-climbing robots is proposed. The novel PMAD can significantly increase the adsorption force under the same mass. Firstly, the magnetic circuit of the novel PMAD was optimized based on the design theory proposed in this paper. The novel PMAD contains multiple closely arranged permanent magnets with different magnetizing directions. The magnets can be divided into several component units by the arrangement regulation of the magnetizing directions. In every component unit, the magnetizing directions distribute along a semi-circle. Secondly, Finite element analysis software Ansys Workbench was used for parameterized modeling, structural characteristic analysis, magnetic circuit simulation, adsorption force calculation and parameter optimization of the novel PMAD. Then, The novel and the Halbach type of PMADs with the same material and volume were trial-produced. The adsorption force was measured under different air gap thicknesses. The experimental results proved that the adsorption force of the novel PMAD doubled averagely compared with the Halbach type of PMAD under the same mass, and the largest amplification was 2.3 times. Finally, the novel PMADs were applied in a wall-climbing robot for ultrasonic testing, and provide steady and reliable adsorption.

Dynamic Modeling and Analysis on a New Type Wall-climbing Robot for Ship Wall Rust Removal

A tracked wall climbing robot for ship rust removal is designed, which is adsorbed by permanent magnetic and vacuum mixed adsorption. The robot has the characteristics of heavy body and heavy load, and the load mass and the center of gravity position change with the climbing high. According to the climbing wall working principle, the kinematics models which contain the robot climbing and turning on the ship wall are established. The models are optimized by using fuzzy optimization theory and analyzed by simulation, and the safe working range is planned. Then the kinematics climbing ability is analyzed, and the relation between upward climbing height and ship wall tilt angle is discussed with theoretical torque, maximum torque and rated torque. An experimental prototype is developed for carrying out wall-climbing turning, fixed load climbing and variable load climbing tests. Simulation and test results show that the optimization model is reliable, the permanent magnetic adsorption force, vacuum force and water jet force have little effect on motion performance, but the robot body weight, wall-climbing height and ship wall tilt angle have great effect on it, and the planned safe working range is reasonable.