Robotic path planning for non-destructive testing - a custom MATLAB toolbox approach

The requirement to increase inspection speeds for non-destructive testing (NDT) of composite aerospace parts is common to many manufacturers. The prevalence of complex curved surfaces in the industry provides motivation for the use of 6 axis robots in these inspections. The purpose of this paper is to present work undertaken for the development of a KUKA robot manipulator based automated NDT system. A new software solution is presented that enables flexible trajectory planning to be accomplished for the inspection of complex curved surfaces often encountered in engineering production. The techniques and issues associated with conventional manual inspection techniques and automated systems for the inspection of large complex surfaces were reviewed. This approach has directly influenced the development of a MATLAB toolbox targeted to NDT automation, capable of complex path planning, obstacle avoidance, and external synchronization between robots and associated external NDT systems. This paper highlights the advantages of this software over conventional off-line-programming approaches when applied to NDT measurements. An experimental validation of path trajectory generation, on a large and curved composite aerofoil component, is presented. Comparative metrology experiments were undertaken to evaluate the real path accuracy of the toolbox when inspecting a curved 0.5 m2 and a 1.6 m2 surface using a KUKA KR16 L6-2 robot. The results have shown that the deviation of the distance between the commanded TCPs and the feedback positions were within 2.7 mm. The variance of the standoff between the probe and the scanned surfaces was smaller than the variance obtainable via commercial path-planning software. Tool paths were generated directly on the triangular mesh imported from the CAD models of the inspected components without need for an approximating analytical surface. By implementing full external control of the robotic hardware, it has been possible to synchronise the NDT data collection with positions at all points along the path, and our approach allows for the future development of additional functionality that is specific to NDT inspection problems. For the current NDT application, the deviations from CAD design and the requirements for both coarse and fine inspections, dependent on measured NDT data, demand flexibility in path planning beyond what is currently available from existing off-line robot programming software

DEVELOPMENT OF GRAPHICAL USER INTERFACE FOR MICROWAVE FILTER DESIGN

Microwave filters play a sterling role in wireless communication systems and they are used to discriminate between wanted and unwanted signal frequencies. Designing microwave filter is a long process in going from the given specification through the synthesis and simulation to the final prototype. However, due to the unavailability of synthesized theoretical values of reactive elements in the market, the result may disagree with the expected output. Moreover, the existing software tools cover only conventional filter topologies; modern microwave filter topologies such as Ultra Wideband (UWB) filter are not yet incorporated into these software tools. In addition, they are costly and not easy to us

Influences of the effective use of a computer simulation on learning in physical science

One of the most attractive instruments in science education is digital simulation. The investigations were conducted utilizing a pre-test and post-test methodology with Moroccan students enrolled in the second year of the natural sciences option secondary certificate at the Abdellah Laroui High School in the city of Fez. In this paper, we assess the effects of including a digital simulation on high school students’ understanding of RLC (a linear circuit containing an electrical resistance, an inductor, and a capacitor) (25 students). There is a substantial difference between the means of the tests administered to the control (M-Cont) and experimental (M-Exp) classes (M-Exp-M-Cont=15.32–3.08=2.24>0), based on a student’s analysis of the two classes’ test scores using a t-test. This study found that using a digital simulation in an educational setting allows for the acknowledgment of the added value and has a favorable impact on student learning, notably in the study of free oscillations in an RLC circuit

Remote control of a robotic unit: a case study for control engineering formation

Hands-on experimentation has widely demonstrated its efficacy in engineering training, especially in control formation, since experimentation using computer-aided control system design (CACSD) tools is essential for future engineers. In this context, this article describes a case study for Control Engineering formation, based on a new lab practice for the linear and angular velocity control for a commercial P3-DX robot platform, to teach industrial control. This lab proposal includes all the stages involved in the design of a real control system, from plant identification from an open-loop test to real experimentation of the designed control system. The lab practices proposed have a twofold objective: First, it is an interdisciplinary approach that allows students to put into practice the skills from other subjects in the curriculum, facilitating the integration of knowledge. In addition, it allows increasing the motivation of the students by working with a complex and realistic plant. The proposal has been evaluated through the grades of the students, as well as the perception of both students and instructors, and the results obtained allow to confirm the benefits of the proposal.Universidad de Alcal

Robotic path planning for non-destructive testing of complex shaped surfaces

The requirement to increase inspection speeds for non-destructive testing (NDT) of composite aerospace parts is common to many manufacturers. The prevalence of complex curved surfaces in the industry provides significant motivation for the use of 6 axis robots for deployment of NDT probes in these inspections. A new system for robot deployed ultrasonic inspection of composite aerospace components is presented. The key novelty of the approach is through the accommodation of flexible robotic trajectory planning, coordinated with the NDT data acquisition. Using a flexible approach in MATLAB, the authors have developed a high level custom toolbox that utilizes external control of an industrial 6 axis manipulator to achieve complex path planning and provide synchronization of the employed ultrasonic phase array inspection system. The developed software maintains a high level approach to the robot programming, in order to ease the programming complexity for an NDT inspection operator. Crucially the approach provides a pathway for a conditional programming approach and the capability for multiple robot control (a significant limitation in many current off-line programming applications). Ultrasonic and experimental data has been collected for the validation of the inspection technique. The path trajectory generation for a large, curved carbon-fiber-reinforced polymer (CFRP) aerofoil component has been proven and is presented. The path error relative to a raster-scan tool-path, suitable for ultrasonic phased array inspection, has been measured to be within ± 2mm over the 1.6 m2 area of the component surface

Development of Sustainable Methodologies in Product Design, Manufacturing and Education

The influence of sustainability in product design and manufacturing processes can be considered from two different points of view: the design of sustainable products and the sustainable manufacturing of those products. Of course, a basic assumption for the aforementioned elements to be realized is the appropriate training and education for sustainability of the young designers and engineers. In this research, sustainability has been applied to many fields, including design, manufacturing and education acting as an umbrella which covers all the three elements and has as the main target to promote sustainability. In today’s world, in which a considerable number of contrasting signs reveal that our society is currently contributing to the planet’s collapse, a new kind of engineer is needed, an engineer who is fully aware of what is going on in society and who has the skills to deal with aspects of sustainability. According to the literature review on the state-of-the-art associated to the subject, in the current research were developed tools and methodologies for the promotion of sustainability aspects that are related to product design, manufacturing and education. Product DesignThe research work was based on a framework, which was built according to the direct communication between users and designers. There is a need for a cultural transformation, which can be focused on consumers and promote the needed behavioural change. Moreover there is a need for a cultural transformation on the role of designers and engineers to the product design process, with an aim to address sustainability as well as emerging priorities from societal to environmental challenges. New tools and methodologies were generated, in order to promote sustainability to the users/citizens bringing them inside to the product design process, giving them the opportunity to be a vital part of it. ManufacturingSustainable manufacturing faces new challenges for developing predictive models and optimization techniques in order to produce more products. The first part of the current is related to the drilling process and cutting tool technology. The creation of mathematical models focused on maximization of productivity and cost reduction by identifying crucial parameters and processes influencing manufacturing effectiveness. The second part of the current research is associated to the development of models used by CAD/ CAM that allow a rapid improvement and an efficient design and manufacture.EducationThe third aspect of the research is associated with the education related to sustainability. The engineering students should develop sustainability competences such as critical thinking, systemic thinking, obtaining values consistent with the sustainability paradigm, except of just taking a course on sustainability, focus on the technological role of sustainability. Focus on that the current research was based on sustainable characteristics such as a) remote control freeware applications, b) share of valuable resources, c) distance learning methodology and d) active participation of the students.<br /

Integrated technologies instructional method to enhance bilingual undergraduate engineering students

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonMathematics permeates almost every aspect of human life and it is a skill much needed by the increasingly complex technological world. It is necessary that this essential skill must be properly developed among students to prepare them for future academic and professional careers. An assessment of the research-based instructional strategies blending with old traditional methods with the modern technological development is a must. Due to the complexity of mathematics learning and the varied learning styles of learners, an integration of appropriate multiple instructional strategies into mathematics education will positively impact mathematical achievement of students. The purpose of this research was to examine the effects of the use of Integrated Technologies Instructional Method (ITIM) as a supplement to the traditional lecture method on mathematics achievement of the Integral Calculus students at the College of Engineering, University of Ha'il, Saudi Arabia. The ITIM includes the four instructional strategies such as the use of the Computer-Supported Collaborative Learning, the collaborative learning, the bilingual support and the study support. Different types of academic supports have been used to examine their effects on students achievement in mathematics. Mathematics, the bedrock of science and engineering, is considered a very important indicator of a student's academic success in professional higher education. Undergraduate engineering students' low achievement in the first year mathematics is an issue demands much attention. The study was undertaken to address students' weak background in mathematics and particularly their high failure rates in this particular course. A total of 218 undergraduate engineering students, comprising of both the experimental and the control groups, were involved in this experimental design study. The control group was taught by the traditional lecture method whereas the experimental group was exposed to the ITIM as a supplement to the traditional lecture method. Apart from the effects of the use of ITIM, students' performance in the previous courses (covariates) such as mathematics, computer, and the English language were compared with their final grades of the Integral Calculus course. The final grades of students were taken as the dependent variable and the ITIM and students' scores in the previous courses as the independent variables. It has been noticed from the literature review that the application of only one instructional strategy does not address the needs of the diverse learning styles of students. A mixed mode method, quantitative and qualitative, was used to collect and analyse data. The quantitative data instruments included students' final exam grades and the student questionnaires. Interviews with students were used as qualitative tools of data collection. An independent t-test, ANOVA, univariate analysis and the stepwise multiple regression analysis were performed to determine the overall statistical significance. The study concluded that there was a statistically significant difference in the performance of the experimental group of students' in terms of their end-of-course grades compared to that of the control group. The regression model revealed significance of covariates on the dependent variable. However, no significant relationship was found between the mathematics achievement and attitudes towards the use of ITIM. The study was an attempt to demonstrate the suitability of the instructional strategies on the bilingual Arab undergraduate engineering students; however, they can probably be applicable to other bilingual students

Parametric modeling for simulation based hypersonic vehicle design

The conceptual design stage offers the most opportunity for innovation and the capability to reveal costly design errors early. Integrating high fidelity design and simulation tools into the conceptual design stage enables engineers to develop design variations quickly and affordably. This work focuses primarily on the development and utilization of parametric modeling methods as they apply to a simulation based design process. It will also address the impacts to conceptual design development time. A blended wing-body (BWB) hypersonic wave rider demonstrates how state-of-the-art solid modeling techniques can be coupled to high fidelity CFD analysis codes to perform top down design. Performance trends are identified for several trade study variations which represent a single iteration through the simulation based design process. Performance metrics are based on interpretations from higher level customer, regulatory, business, and other requirements. The process of cascading these requirements down to the component level is the definition of top-down-design. This bidirectional tracing of requirements allows vehicle development to progress in a manner such that any change of the vehicle can be assessed in terms of the overarching requirements

Machining-based coverage path planning for automated structural inspection

The automation of robotically delivered nondestructive evaluation inspection shares many aims with traditional manufacture machining. This paper presents a new hardware and software system for automated thickness mapping of large-scale areas, with multiple obstacles, by employing computer-aided drawing (CAD)/computer-aided manufacturing (CAM)-inspired path planning to implement control of a novel mobile robotic thickness mapping inspection vehicle. A custom postprocessor provides the necessary translation from CAM numeric code through robotic kinematic control to combine and automate the overall process. The generalized steps to implement this approach for any mobile robotic platform are presented herein and applied, in this instance, to a novel thickness mapping crawler. The inspection capabilities of the system were evaluated on an indoor mock-inspection scenario, within a motion tracking cell, to provide quantitative performance figures for positional accuracy. Multiple thickness defects simulating corrosion features on a steel sample plate were combined with obstacles to be avoided during the inspection. A minimum thickness mapping error of 0.21 mm and a mean path error of 4.41 mm were observed for a 2 m² carbon steel sample of 10-mm nominal thickness. The potential of this automated approach has benefits in terms of repeatability of area coverage, obstacle avoidance, and reduced path overlap, all of which directly lead to increased task efficiency and reduced inspection time of large structural assets