Robotized Inspection System of the External Aircraft Fuselage based on Ultrasound

This paper describes an automated system that inspects the external surface of an aircraft section. To test the system developed, a part similar to airplane section 19 has been used. The inspection system is based on a robot carrying a headset made up of ultrasound sensors. Data are processed by an ultrasound processing program which maps the mechanical features of the inspected surface. The main requirement of the inspection is to perform the proper contact between the ultrasound sensors and the inspected surface. In order to guarantee suitable contact between them, a robot trajectory correction system running in real time has been applied. It is based on the measures given by four optical sensors located on the sides of the ultrasound headset. The integration and synchronization of the devices mentioned above make it possible to obtain an adequate inspection system for the external aircraft fuselage. Furthermore, inspection time has been significantly reduced; at the same time a fully-automated system has been developed to inspect the whole aircraft section surfac

Recent advances in active infrared thermography for non-destructive testing of aerospace components

Active infrared thermography is a fast and accurate non-destructive evaluation technique that is of particular relevance to the aerospace industry for the inspection of aircraft and helicopters’ primary and secondary structures, aero-engine parts, spacecraft components and its subsystems. This review provides an exhaustive summary of most recent active thermographic methods used for aerospace applications according to their physical principle and thermal excitation sources. Besides traditional optically stimulated thermography, which uses external optical radiation such as flashes, heaters and laser systems, novel hybrid thermographic techniques are also investigated. These include ultrasonic stimulated thermography, which uses ultrasonic waves and the local damage resonance effect to enhance the reliability and sensitivity to micro-cracks, eddy current stimulated thermography, which uses cost-effective eddy current excitation to generate induction heating, and microwave thermography, which uses electromagnetic radiation at the microwave frequency bands to provide rapid detection of cracks and delamination. All these techniques are here analysed and numerous examples are provided for different damage scenarios and aerospace components in order to identify the strength and limitations of each thermographic technique. Moreover, alternative strategies to current external thermal excitation sources, here named as material-based thermography methods, are examined in this paper. These novel thermographic techniques rely on thermoresistive internal heating and offer a fast, low power, accurate and reliable assessment of damage in aerospace composites

Damage monitoring of aircraft structures made of composite Materials using wavelet transforms

Due to the significant increase in composite materials that can be used in aviation structural elements, there is a strong need for their operational control. It is estimated that a significant part of the average modern aircraft lifecycle costs is related to inspection and repair, thus it is important to perform efficient and cost-effective maintenance and monitoring techniques to reduce lifetime costs. This study is concerned with integral state monitoring of aircraft structures made from composite materials. It deals with techniques for damage monitoring and quality control, equipment observation, planned prototype testing and research into the vibration properties of different composite structures. Operation, maintenance and condition forecasting of components, such as aircraft composite blades, airplane spoilers, ailerons, aircraft airframe components, are the areas that should be properly investigated, in order to enhance the future of the industry. The aim of this research is to investigate usable signs of vibration characteristics that can reflect the effects of the damage and integral changes of advanced composite structures. The main goals are a universal approach to integral condition monitoring for all kinds of composite materials and research into the vibration property alterations of a new generation of composite materials during their operation. The modern generation of large aircraft can be designed with all-composite fuselage, frames and wing structures. The main advantages of composite materials are their high strength, relatively low weight, corrosion resistance and flexibility in implementation. Control and diagnostics of this kind of composites require deep knowledge of composite structures, materials, their failure behaviour, and tooling. Aerospace structures are suffering from damage as a result of fatigue, overloading, partial or integral material destruction and degradation in consequence of environmental factors, and extemporaneous incidents such as seismic events or impacts. There is also uncertainty connected to understanding the outcome of operational damage of aircraft composite structures. Non-destructive inspection and evaluation techniques are recommended in many cases, but still, represent significant downtime and labour costs and, in many cases, require highly skilled personnel to perform them. Linked to structures and onboard built-in structural health monitoring systems could be used for improving the reliability and safety of composites while reducing lifecycle costs and improving the design and manufacture processes. However, they also have their own disadvantages like the cost of implementation, cost of operation of the system itself and impact to the structure during production and maintenance. This research is therefore mainly focused on vibration properties of advanced composite materials and simple control procedures that can be conducted by an engineering technician during light maintenance checks (including both routine and detailed inspections). The decision on the schedule for the checks to be performed can vary by aircraft type, the cycle count, or the number of hours flown since the last check. Another important subtask is the prediction of the object condition in operation. A significant part of the research is concerned with the collection of statistical information, and experiments with different objects made of composite materials, using the proposed methodology. An additional part is linked to the optimization of equipment for the future demands of the industry in operational control and diagnostics. It is concluded that the technique of combining wavelet analysis is an effective and appropriate tool for vibration analysis to determine the modal parameters of free and forced oscillations, especially in the integral control of composite structural elements. The novel aspect of the research is the practical experimental work that has been executed on real advanced composite material objects (metal-polymer-metal composites as well), and its subsequent analysis

Residual stress effects and damage tolerance behaviour of integral lightweight structures manufactured by FSW and HSM

Estágio realizado na empresa Airbus Operations GmbH, orientado pelo Mr. Marco PacchioneTese de Programa Doutoral. Engenharia Mecânica. Universidade do Porto. Faculdade de Engenharia. 201

Application of millimeter-wave differential probe for crack detection on riveted structures

This thesis proposes the use of a W-band wideband differential probe for crack detection on riveted structures, such as aircraft fuselage lap joints. Detection of crack at its early stage (surface-breaking) is particularly important to prevent the development of a fatigue crack. This probe utilizing millimeter-wave frequencies serves as a viable candidate on detecting surface-breaking cracks, as it can be employed in measurements in a non-contact fashion, while allowing for high spatial-resolution images and the abilities to penetrate through dielectric materials (paint), making it attractive for detecting small cracks. In previous works, a V-band differential probe has shown promise for detecting surface breaking crack near a fastener head. This work is extended in this thesis by investigating the surface crack detection capability of the W-band differential probe. The W-band probe is tested with various intentional misalignments of the probe, as well as a paint layer covering the crack, the variations in its crack detection capability are then observed. The measurement results indicate that this fabricated probe is capable of detecting a surface crack at a length of 1.27 mm (adjacent to a fastener head), and the detection is not significantly affected by a slight misalignment, although consequently some undesired signals may also be registered. In addition, a layer of thick paint over crack introduces uncertainties to the detection signals and complicates the evaluations. To reduce the significance of these undesired signals, SAR filter is applied to the results. The outcome demonstrates an enhanced crack detection and weakened undesired signals, but the influence of a thick paint layer cannot be completely removed. A more in-depth analysis regarding the influence of paint on crack detection may be desired to fully understand the crack detection capabilities of the W-band differential probe --Abstract, page iii

Welding Processes

Despite the wide availability of literature on welding processes, a need exists to regularly update the engineering community on advancements in joining techniques of similar and dissimilar materials, in their numerical modeling, as well as in their sensing and control. In response to InTech's request to provide undergraduate and graduate students, welding engineers, and researchers with updates on recent achievements in welding, a group of 34 authors and co-authors from 14 countries representing five continents have joined to co-author this book on welding processes, free of charge to the reader. This book is divided into four sections: Laser Welding; Numerical Modeling of Welding Processes; Sensing of Welding Processes; and General Topics in Welding

Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018

Contemporary Robotics

This book book is a collection of 18 chapters written by internationally recognized experts and well-known professionals of the field. Chapters contribute to diverse facets of contemporary robotics and autonomous systems. The volume is organized in four thematic parts according to the main subjects, regarding the recent advances in the contemporary robotics. The first thematic topics of the book are devoted to the theoretical issues. This includes development of algorithms for automatic trajectory generation using redudancy resolution scheme, intelligent algorithms for robotic grasping, modelling approach for reactive mode handling of flexible manufacturing and design of an advanced controller for robot manipulators. The second part of the book deals with different aspects of robot calibration and sensing. This includes a geometric and treshold calibration of a multiple robotic line-vision system, robot-based inline 2D/3D quality monitoring using picture-giving and laser triangulation, and a study on prospective polymer composite materials for flexible tactile sensors. The third part addresses issues of mobile robots and multi-agent systems, including SLAM of mobile robots based on fusion of odometry and visual data, configuration of a localization system by a team of mobile robots, development of generic real-time motion controller for differential mobile robots, control of fuel cells of mobile robots, modelling of omni-directional wheeled-based robots, building of hunter- hybrid tracking environment, as well as design of a cooperative control in distributed population-based multi-agent approach. The fourth part presents recent approaches and results in humanoid and bioinspirative robotics. It deals with design of adaptive control of anthropomorphic biped gait, building of dynamic-based simulation for humanoid robot walking, building controller for perceptual motor control dynamics of humans and biomimetic approach to control mechatronic structure using smart materials

Advances in Intelligent Robotics and Collaborative Automation

This book provides an overview of a series of advanced research lines in robotics as well as of design and development methodologies for intelligent robots and their intelligent components. It represents a selection of extended versions of the best papers presented at the Seventh IEEE International Workshop on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications IDAACS 2013 that were related to these topics. Its contents integrate state of the art computational intelligence based techniques for automatic robot control to novel distributed sensing and data integration methodologies that can be applied to intelligent robotics and automation systems. The objective of the text was to provide an overview of some of the problems in the field of robotic systems and intelligent automation and the approaches and techniques that relevant research groups within this area are employing to try to solve them.The contributions of the different authors have been grouped into four main sections:• Robots• Control and Intelligence• Sensing• Collaborative automationThe chapters have been structured to provide an easy to follow introduction to the topics that are addressed, including the most relevant references, so that anyone interested in this field can get started in the area