Inspection Robot Research Articles

Study on the performance of vortex suction cup for an underwater inspection robot

Using robots to detect Marine structures is very important for maintaining the safety of Marine structures. This paper presents an underwater inspection robot specifically engineered for the assessment of underwater structures. The integration of reliable adhesion technology is identified as a critical factor in the development of such robots. The vortex suction cup, employed by the robot as its primary adhesion mechanism, outperforms traditional adhesion methods by enabling non-contact attachment while consuming less power. As the vortex suction cup is the core component of the underwater inspection robot , this study comprehensively investigates how variations in the vortex suction cup’s structural and operational parameters influence its adhesion performance, measured from an energy efficiency ratio perspective. Initially, we delineate the vortex suction cup’s design and succinctly explicate the mechanism underpinning the generation of negative pressure. Subsequently, we establish an evaluative parameter, the energy efficiency ratio (η=F/P), that is, the adsorption force obtained per watt of power consumption of the suction cup, serving as a metric for the adhesion performance. By simulating the structural and operational parameters of the suction cup, we extract the corresponding adhesion force, torque, and energy efficiency ratio. Lastly, we construct an experimental apparatus to measure the suction cup’s adhesion force and output torque, validating the veracity of the simulated outcomes. Our simulation and experimental findings indicate that increasing the height of the suction cup housing enhances the adsorption force, however, this simultaneously diminishes its energy efficiency ratio performance. Likewise, an increase in the chamber inner radius amplifies the adhesion force, and the energy efficiency ratio commensurately increases. Augmenting the radius of the negative pressure effect board improves the adhesion force, decreases the required torque, and consequently amplifies the energy efficiency ratio. The suction cup’s adhesion force and required torque display a direct relationship with its speed, but the energy efficiency ratio is minimally affected by speed. When the distance is close (h ¡ 4 mm), changes in the adhesion gap profoundly impact the suction cup’s torque and energy efficiency ratio. However, when the adhesion gap ranges between 5–15 mm, the energy efficiency ratio exhibits a gradual decline.

A patent text-based product conceptual design decision-making approach considering the fusion of incomplete evaluation semantic and scheme beliefs

Conceptual design evaluation is a significant challenge in product development to select suitable conceptual schemes (CS). Relying on decision makers' (DMs) personal experience for design information may result in incomplete and ambiguous evaluation semantics, creating an incomplete decision matrix. Previous approaches use attributes based on candidate schemes to complete the missing information, but neglect the mining of associated design information from external resources such as patents, reducing the beliefs objectivity after missing semantic completion. Besides, non-compensatory nature between DMs’ interactivity and criteria have not been well considered. To fill these issues, a patent text-based CS decision approach considering the fusion of incomplete semantics and scheme beliefs is proposed. First, using the beneficial effects text from patents as historical design data, constructing general evaluation criteria using the Latent Dirichlet Allocation topic model, and introducing the Apriori model to extract strong association rules between criteria to complete the incomplete semantics. Second, a fuzzy measure model for DMs is constructed based on intuitionistic fuzzy cross-entropy and Shapley value method, supporting the allocation of DMs' interactive weights. Then, the fuzzy Dempster-Shafer evidence theory is used to transform the multi-criteria decision model into a belief fusion problem of CS that avoids aggregating the evaluation semantics of non-compensatory criteria and outputting the optimal CS with interval credibility. A practical case study of an in-pipe inspection robot will be employed to validate the proposed approach, sensitivity analysis and comparison results confirmed that the complement data have the reliability to avoid continuous investment in the evaluation process.

Design of a wheeled-type In-Pipe Inspection Robot to overcome motion singularity in curved pipes

This paper discusses the development and design of two wheeled-type In-Pipe Inspection Robots (IPIRs), Kuzhali I and Kuzhali II, which were created to address the limitations of traditional human inspection methods and earlier robot designs. Specifically, the robots aim to overcome the motion singularity experienced by IPIRs when navigating through curved pipes. Kuzhali I was developed with wheels mounted at an asymmetric angle, which enables the wheels to maintain contact with the pipe’s surface, preventing motion singularity. However, Kuzhali I had limitations due to its prismatic mechanism, and thus Kuzhali II was developed with a telescopic mechanism to allow it to pass through vertical pipes with obstacles. Motion analysis was conducted on both robots to demonstrate how they overcome motion singularity and navigate through straight and curved pipelines. Simulation results showed that the forces acting on the robots’ wheels fell within 5 N to 12 N, demonstrating stability while navigating pipeline junctions. Experimental tests were conducted on Kuzhali II, and the results were compared to simulation results, showing an error of less than 5%. The results of the experiments indicate that Kuzhali II is safe to use for pipeline inspection, can navigate through vertical pipelines with ease and can overcome motion singularity in curved pipes. These robots offer a faster, more accurate, and safer alternative to human inspection, which can reduce the risk of pipeline failures and associated environmental and safety hazards.

An image processing mechanism for aerial inspection robots to detect submillimeter-width concrete cracks in social infrastructures

Inspection robots for early detection of potential risks in severe environments require a high accuracy like human experts. A fine mechanism is crucial for extracting target components from noisy signals. We have proposed a detection system for submillimeter-width cracks in concrete surfaces of social infrastructures, such as bridges, by using morphological component analysis (MCA), for aerial image-inspection robots. Traditional schemes like PCA have relied on linear decomposition for the separation of target signal and noise components. Recent advancement in signal decomposition focuses on the enhancement of linearity in the separation by introducing a set of nonlinear basis functions to represent the raw signal even when multiple factors are mixed in a nonlinear manner. In this sense, MCA is a core technique to be able to isolate target components to represent submillimeter-width cracks from others. We proposed a proper pre- and post-processing operations to attach MCA, which demonstrated a high accuracy yet coarse and fine image components have to be integrated redundantly. In the present study, we successfully found a simpler mechanism to set the single basis function to extract the target by introducing a new thresholding mechanism. It suggests a high potential of MCA for inspection robots for various purposes.

Design and motion mechanism analysis of screw-driven in-pipe inspection robot based on novel adapting mechanism

AbstractIn the pipeline industry, it is often necessary to monitor cracks and damage in pipelines, or need to clean the inside of the pipeline regularly, or collect adhesive on the inner wall of the pipe, but the pipe is too narrow and difficult for humans to enter, it is necessary to use a pipe machine to complete the work. In this paper, a newly designed screw-driven in-pipe inspection robot (IPIR) is proposed. Compared with common robots, this robot innovatively designs adapting mechanism. The robot can not only adapt to the change of the inner diameter size of the pipeline by using the bionic principle and the deformation characteristics of flexible components but also can pass smoothly in the horizontal/oblique/vertical pipelines and has a certain ability to cross obstacles. In addition, it can transmit images of the inner wall of the pipeline wirelessly for data analysis. Finally, through theoretical analysis and prototype construction, the performance of the robot is verified. The results show that the prototype robot can not only smoothly pass through the acrylic pipe with inner diameter of 120–138 mm but also pass through boss with a height of 3 mm.

Simulation of defect detection for the buried petroleum pipe by the X-ray backscatter imaging

Ensuring the integrity, safety, and compliance of oil pipelines is crucial for operators. Two significant factors affecting pipeline integrity are metal loss due to corrosion or air gouging and the presence of cracks. This paper introduces an X-ray backscatter nondestructive testing model on a smart pig(an intelligent robot) for internal inspection of petroleum pipelines. The paper investigates the X-ray source and detection system, essential components of the backscatter imaging technology, to provide technical guidance for model design. The imaging system’s layout is modeled using GEANT4, and its performance in detecting defects of various formats on pipe walls is studied. The research demonstrates the feasibility of using X-ray backscatter imaging for pipeline inspection and provides insights into different defect detection. The findings contribute to designing and optimizing the robot’s scanning head for effective pipeline inspection.

Perspective deformation correction for circular pointer meter based on prior indication structure feature

The meter verification and industrial inspection robots often use automatic reading of pointer meters. Due to tilt and rotation of circular pointer meter, the perspective deformation may be induced to the captured image, so it will extremely affect the accuracy of automatic reading algorithm based on machine vision. Some existing deformation correction methods suffer from poor universality or low accuracy. The paper bases on prior indication structure feature of circular pointer meter and presents a new deformation correction method. First, the MobileNetV3-UNet network is used to detect the outer-endpoints of long scale lines in deformed meter as the key points. Second, with the help of prior information, the positions of mapping points in standard image are constructed. Third, according to the one-to-one mapping relationship of key points from deformed and standard images, a perspective transform matrix is calculated. Finally, the deformation and rotation correction are performed through inverse perspective transform. The experimental results show that the proposed method has better precision and robustness and works well under different conditions.

Combined navigation system for substation inspection robot based on DGPS/DR multi-sensor fusion

To realize the routine inspection work of the capacitor tower inspection operation robot on the capacitor tower in the substation, and to guarantee the accuracy and safety of the robot’s movement in the substation, a multi-sensor combination navigation system and the corresponding Kalman fusion filter are designed. Combined with the overall structure of the substation and the working environment of the inspection robot, the navigation and positioning requirements of the robot are analyzed and compared, and the multi-sensor combination positioning technology using a combination of DGPS, attitude sensors and velocity sensors is determined. The Kalman fusion filter based on the constant velocity model is used to fuse the positioning information of multiple sensors, and more accurate and reliable navigation information is obtained compared with the single-sensor positioning system. According to the working environment of the substation, an outdoor planar robot mobile navigation experiment is carried out to collect the positioning information of multiple sensors and carry out data fusion processing to verify the accuracy and robustness of multi-sensor combination navigation and positioning.

Pointer instrument positioning and indication recognition algorithm based on YOLOV5s

The substation inspection robot has low accuracy in positioning and indication reading of the pointer instrument. An algorithm design for indicator recognition is proposed. The algorithm mainly includes dial area extraction, scale line extraction and dial center determination, zero scale line determination, and indicator recognition. An experimental system for pointer instrument positioning and indication recognition is constructed to verify the proposed algorithm. The results indicate that the positioning accuracy of the two instruments is 90.5% and 100% respectively. Ten positioned instruments are selected, and the reading recognition error is 0.126. It shows that the proposed pointer instrument positioning and indication recognition algorithm can improve the efficiency of substation instrument recognition.

Gripper vibration analysis of inspection robot during variable working flight of pre-landing on high-voltage transmission line

Gripper vibration analysis of inspection robot during variable working flight of pre-landing on high-voltage transmission line

Research on resistance detection robot for UHV tension insulator string

Insulator inspection robots can realize automatic and rapid inspection of insulators of ultra-high voltage transmission lines, which is an important guarantee equipment for the continuous safe operation of the national power grid. Aiming at the needs of ultra-high voltage insulator string inspection, an insulator robot is designed to realize efficient and stable insulator string motion and insulator detection, and the main work includes proposing a new insulator string motion robot configuration and realizing its string motion and inspection functions in the form of a physical prototype. It has been proved that the robot has a large motion load and strong motion performance, and can be adapted to the complex working conditions consisting of a variety of insulators within a certain size range.

Design of Community Inspection Robot System

With the continuous development of the global economy, urban centers have experienced a consistent increase in size. Consequently, the number of schools, parks and residential communities within cities are also on the rise. The increasing quantity of various types of communities has juxtaposed a notable dilemma: a shortage of security and maintenance personnel. In order to address this issue, employing robotic automated inspection within these communities, coupled with autonomous navigation, obstacle avoidance, and AI recognition technology, is proposed. This project aims to alleviate the burden on human staff, improve recognition accuracy, and enhance the overall efficiency of operation and maintenance. This paper analyzes the operational needs of these communities, presents a design concept for a community inspection robot system, and discusses issues that require further research in the future.

Control of a Path Following Cable Trench Caterpillar Robot Based on a Self-Coupling PD Algorithm

Underground cable trench inspection robots work in narrow, variable friction coefficient, and complex road environments. The running trajectory easily deviates from the desired path and leads to a collision, or even the destruction of the robot or cable. Addressing this problem, a path-following control method for the dual-tracked chassis robot based on a self-coupling PID (SCPID) control algorithm was developed. The caterpillar robot dynamics were modelled and both the unknown dynamics and external bounded disturbances were defined as sum disturbances, thus mapping the nonlinear system into a linearly disturbed system, then the self-coupling PD (SCPD) controller was designed. The system proved to be a robust stability control system and only one parameter, the velocity factor, needed to be tuned to achieve parameter calibration. Meanwhile, to solve the problem that the error-based speed factor is not universal and to improve the adaptive ability of the SCPD controller, an iterative method was used for adaptive tuning. The simulation results showed that the SCPID can achieve better control. The field test results showed that the SCPD’s maximum offset angle was 56.7% and 10.3% smaller than incremental PID and sliding mode control (SMC), respectively. The inspection time of the SCPD was 20% faster than other methods in the same environment.

Advancements in integrated robotic sensing: A European perspective.

Robotic Non-destructive Testing and Sensing stands at the forefront of technological innovation, offering capabilities in assessing structural integrity, safety, and material quality across diverse industries. This comprehensive review article provides a detailed exploration of the field, focusing on the substantial contributions of European researchers and institutions. The need for non-destructive testing has been a constant in industries that rely on structural integrity, including aerospace, manufacturing, energy, construction, and healthcare. Traditional testing methods, such as radiography, ultrasonic testing, magnetic particle testing, and dye penetrant testing, have been integral for quality control and safety assurance. However, the robotisation of such methods has marked a profound shift, enabling precise, fast, efficient, and repeatable testing while minimising human exposure to hazardous environments. European researchers and institutions have played an instrumental role in driving the evolution of integrated robotic sensing. The historical perspective of the field reveals the pioneering spirit of Europe, as collaborative initiatives led to the development of robotic platforms equipped with advanced sensors and testing techniques. A critical aspect of the European impact on robotic inspection applications lies in developing advanced sensors, innovative robotic platforms, novel robotic path-planning and control approaches and data collection and visualisation tools. These developments continue to influence the global landscape of robotic sensing. European researchers remain at the forefront of current trends and innovations as the field continues to evolve. This review article will delve into these recent advancements, highlighting Europe's pivotal role in pushing the boundaries of technology and application. The implications and applications of robotic sensing reverberate across multiple sectors worldwide. From inspecting critical aerospace components to ensuring the quality of manufactured goods, these technologies underpin safety and quality standards.

Integrative Approach for High-Speed Road Surface Monitoring: A Convergence of Robotics, Edge Computing, and Advanced Object Detection

To ensure precise and real-time perception of high-speed roadway conditions and minimize the potential threats to traffic safety posed by road debris and defects, this study designed a real-time monitoring and early warning system for high-speed road surface anomalies. Initially, an autonomous mobile intelligent road inspection robot, mountable on highway guardrails, along with a corresponding cloud-based warning platform, was developed. Subsequently, an enhanced target detection algorithm, YOLOv5s-L-OTA, was proposed. Incorporating GSConv for lightweight improvements to standard convolutions and employing the optimal transport assignment for object detection (OTA) strategy, the algorithm’s robustness in multi-object label assignment was enhanced, significantly improving both model accuracy and processing speed. Ultimately, this refined algorithm was deployed on the intelligent inspection robot and validated in real-road environments. The experimental results demonstrated the algorithm’s effectiveness, significantly boosting the capability for real-time, precise detection of high-speed road surface anomalies, thereby ensuring highway safety and substantially reducing the risk of liability disputes and personal injuries.

Localizing and tracking of in-pipe inspection robots based on distributed optical fiber sensing

Ensuring the safe transportation of energy relies heavily on the timely safety inspection and pigging of energy pipelines using in-pipe inspection robots known as Smart/Intelligent PIGs. Addressing the potential risks of PIG block incidents and the limitations of excessive speed in the maintenance, real-time localization and tracking of these inspection robots has become imperative. However, traditional localization and tracking methods present a challenge due to their resource-intensive nature, requiring significant manpower and resources. To overcome this limitation and enhance the intelligence of the robot operation monitoring, this paper proposes an innovative artificial intelligence (AI) integration algorithm framework based on distributed optical fiber sensing (DOFS) for real-time localization and tracking of robots. It adopts noise reduction and reconstruction techniques in signal processing, effectively enhancing the quality of optic fiber vibration signals. Notably, the integration of two distinct features that complement each other enables dual verification of tracking detection, ultimately bolstering the system’s effectiveness and trustworthiness. Besides, a logical reasoning-based localization decision strategy further enhances the system’s capabilities, allowing for controlled tracking intervals and step sizes that can be tailored to meet the task requirements under diverse working conditions. The collaboration of three modules makes it feasible to monitor dynamic changes of the detection robot in the pipeline along the direction of operation. The experimental results convincingly demonstrate that the integrated framework possesses several key advantages of remarkable robustness, real-time performance, and minimal error. It underscores the system’s potential to ensure energy pipeline safety efficiently and effectively.

A heavy-load wall-climbing robot for bridge concrete structures inspection

Purpose The purpose of this paper is to present a wall-climbing robot platform for heavy-load with negative pressure adsorption, which could be equipped with a six-degree of freedom (DOF) collaborative robot (Cobot) and detection device for inspecting the overwater part of concrete bridge towers/piers for large bridges. Design/methodology/approach By analyzing the shortcomings of existing wall-climbing robots in detecting concrete structures, a wall-climbing mobile manipulator (WCMM), which could be compatible with various detection devices, is proposed for detecting the concrete towers/piers of the Hong Kong-Zhuhai-Macao Bridge. The factors affecting the load capacity are obtained by analyzing the antislip and antioverturning conditions of the wall-climbing robot platform on the wall surface. Design strategies for each part of the structure of the wall-climbing robot are provided based on the influencing factors. By deriving the equivalent adsorption force equation, analyzed the influencing factors of equivalent adsorption force and provided schemes that could enhance the load capacity of the wall-climbing robot. Findings The adsorption test verifies the maximum negative pressure that the fan module could provide to the adsorption chamber. The load capacity test verifies it is feasible to achieve the expected bearing requirements of the wall-climbing robot. The motion tests prove that the developed climbing robot vehicle could move freely on the surface of the concrete structure after being equipped with a six-DOF Cobot. Practical implications The development of the heavy-load wall-climbing robot enables the Cobot to be installed and equipped on the wall-climbing robot, forming the WCMM, making them compatible with carrying various devices and expanding the application of the wall-climbing robot. Originality/value A heavy-load wall-climbing robot using negative pressure adsorption has been developed. The wall-climbing robot platform could carry a six-DOF Cobot, making it compatible with various detection devices for the inspection of concrete structures of large bridges. The WCMM could be expanded to detect the concretes with similar structures. The research and development process of the heavy-load wall-climbing robot could inspire the design of other negative-pressure wall-climbing robots.

Dimensional synthesis of an Inspection Robot for SG tube-sheet

To ensure the operational safety of nuclear power plants, we present a Quadruped Inspection Robot that can be used for many types of steam generators. Since the Inspection Robot relies on the Holding Modules to grip the tube-sheet, it can be regarded as a hybrid robot with variable configurations, switching between 4-RRR-RR, 3-RRR-RR, and two types of 2-RRR-RR, and the variable configurations bring a great challenge to dimensional synthesis. In this paper, the kinematic model of the Inspection Robot in multiple configurations is established, and the analytical solution is given. The workspace mapping is analyzed by the solution-space, and the workspace of multiple configurations is decomposed into the workspace of 2-RRR to reduce the analysis complexity, and the workspace calculation is simplified by using the envelope rings. The optimization problem of the manipulator is transformed into the calculation of the shortest contraction length of the swing leg. The switching performance of the Inspection Robot is evaluated by stride-length, turning-angle, and workspace overlap-ratio. The performance indexes are classified and transformed based on the proportions and variation trends of dimensional parameters to reduce the number of optimization objective functions, and Pareto optimal solutions are obtained using an intelligent optimization algorithm.

Research on inspection route of hanging environmental robot based on computational fluid dynamics

The environment of a closed piggery is commonly characterized by spatial unevenness, and there are currently no specific standards for installation points of various environmental monitoring sensors. Therefore, the project team used the hanging track inspection robot (HTIR) as an environmental mon-itoring platform to seek the environmental monitoring points and ensure the scientific layout of moni-toring points. Ansys-CFD software was used to study the change rules of environmental parameters at 1.6 m (α plane), 0.7 m (β plane), and 0.4 m (γ plane) above the ground. The 300 monitoring points ((x1~x30) ×(y1~y10)) in each plane were analyzed to determine the most suitable monitoring points and inspection routes for HTIR. The results showed that: (1) All monitoring points could be arranged directly below the y3 track. (2) Monitoring points (x1, y3), (x10, y3) and (x30, y3) were environmental feature points. At (x1, y3), the maximum relative humidity and NH3 concentration on the α plane could be detected, and the maximum wind speed, maximum temperature, and maximum NH3 concentration on other planes could also be detected; At (x10, y3), the minimum temperature and maximum relative humidity of the β and γ planes could be detected; At (x30, y3), the maximum NH3 concentration in the α plane and the minimum relative humidity in all planes could be detected. This study scientifically arranged the inspection track and monitoring points for HTIR, improved the accuracy of environmental monitoring, and put forward suggestions for reducing NH3 concentration in closed piggeries, laying the foundation for the next step.

Verification and Validation of Camera Based Robotic Inspection System via Camera Fault Injection Tool

Günümüzde, gelişen görüntü işleme teknikleri ile birlikte kamera tabanlı robotik inceleme sistemleri oldukça popülerlik kazanmıştır. Bu tür sistemler gıdadan, askeriyeye birçok sektörde yoğun olarak kullanılmaktadır. Bu sistemler geliştirilirken gerekli olan doğrulama ve onaylama süreçleri oldukça uzun ve maliyetli olmaktadır. Bu çalışma, kamera tabanlı endüstriyel robotik sistemler üzerinde doğrulama ve onaylama faaliyetlerini gerçekleştirmek ve iyileştirmek amacıyla geliştirilmiştir. RGB ve TOF kameralara farklı türlerde (Open, Close, Dilation, Erosion, Gradient, Motionblur, Tuz&Biber, Gaussian ve Poisson) hata enjeksiyon yöntemleri kullanılmasını mümkün Kamera Hata Enjeksiyon Aracı (CamFITool) ile gerçekleştirilmiş testler ve sonuçlar açıklanmıştır. Yapılan çalışma, VALU3S projesi kapsamında, OTOKAR’ın ROKOS robotik sistemine, CamFITool ile gerçek ortamdan alınmış kamera görüntülerinden oluşan kitaplıklara, çeşitli konfigürasyonlarda hatalar enjekte edilip, bu enjeksiyonun sisteme etkilerinin incelenmesine odaklanmıştır. Bu kapsamda 49 farklı test komfigürasyonunda hata enjeksiyonu gerçekleştirilmiştir. Sonuç olarak, kamera tabanlı endüstriyel robotik sistemlerin daha güvenli ve stabil çalışmalarının sağlanması için, bu sistemlerin hataya dayanıklı olup olmadıklarını test eden açık kaynaklı bir hata enjeksiyon aracı olan CamFITool önerilmiştir.