Criteria

Text:
Display:

Results

Viewing 1 to 30 of 572
2017-09-19
Technical Paper
2017-01-2074
Thorsten Dillhoefer
Ever increasing process applications inspire us, as suppliers of aircraft, structural-assembly, and equipment to design innovative and modular, manufacturing cells in compliance with modern specifications. The result is the new flexible C-Frame Panel Assembly Cell (CPAC) Bulkhead riveting System. This paper describes how benchmarks for flexible automated drilling and fastening are being achieved with the CPAC.
2017-09-19
Technical Paper
2017-01-2077
John McClelland, Michael Morgan, Caroline McClory, Colm Higgins, Rory Collins, Adrian Murphy, Yan Jin
The need to drill several million holes per aircraft through composite and hybrid material stacks is a large challenge for the aerospace assembly process. The ability to produce high quality holes for the lowest tooling costs is at the forefront of requirements for aircraft assembly factories worldwide. Consequently, much research has been conducted into tool design and development, however, the effect of drilling platform characteristics has not been well covered in literature. Respectively, this research has compared the drilling abilities of a 5-axis precision CNC platform, a hybrid parallel kinematic machine and an articulated robotic arm fitted with a drilling module. In-process force measurement and post process hole and tool analysis methods were used to better understand the effect of static and dynamic platform characteristics on the achievable hole quality, cycle time and tool wear when drilling aerospace metal alloy stacks.
2017-09-19
Technical Paper
2017-01-2084
Karl-Erik Neumann
True Mobile/Portable Drilling & Machining, a Paradigm Shift in Manufacturing The evolving Aerospace manufacturing environment has created challenges that until now, are not achievable with standard machine tools, large monumental gantry style machines, robots or even manually. The solution is a lightweight, portable, modular, mobile solution capable of machining to high tolerances, with minimal time and effort to relocate to a different area, and capable of machining a different part, or be reconfigured to machine in a different orientation…….at an affordable price. With the carbon fiber PKM mounted on the flexible mobile manufacturing stand, the module can be simply relocated using a standard fork lift to any area of the factory. The module can also be easily removed from the mobile platform and mounted in a desired location, in any orientation. It can also can be disassembled into modules, and reconstructed in an area, that is not typically accessible by machines or robots.
2017-09-19
Technical Paper
2017-01-2087
Peter Mueller-Hummel, Alex Hjorten
This article characterizes the special features of machining composites in comparison to machining metal. Simplified theoretic models will demonstrate how CFRP should be machined without delamination, burn marks and cutting tool breakages. Different strategies can be chosen depending on the material removal rate. The paper will present, based on this analytical approach, how a drill should be designed in order to avoid the entrance, inner and exit delamination. While entrance and exit delamination is well understood, the paper will focus more to the delamination inside the bore. The appearance and the avoidance of the so called "Volcano Effect" and the reason why holes in composite becomes smaller after a couple of days will be explained. The comparison between 4 different cutting tool technologies will prove and give a better understanding how to use this theoretical approach.
2017-09-19
Technical Paper
2017-01-2088
Long Yu, Qingzhen Bi PhD, Yilian Zhang, Yuhan Wang
A novel normal measurement device for robotic drilling and countersinking has been developed in this paper. This device is mainly composed of three contact displacement sensors and a spherically compliant clamp pad. The compliance of the clamp pad allows it to be perpendicular to the part when the Multi-Function End Effector (MFEE) drives it to clamp the part surface prior to drilling, while the displacement sensors are used to measure the movement of the clamp pad relative to the MFEE. Once the sensors’ position is calibrated, the rotation angle of the clamp pad can be calculated by the displacement of the sensors. Then, the normal adjustment of MFEE is obtained, and the adjustment process can be achieved by the Tool Center Point (TCP) function of robot. Thus, an innovative method based on laser tracker to identify the position of sensors is proposed.
2017-09-19
Technical Paper
2017-01-2081
Richard Kasler, Agata Suwala, Ashwin Gomes
One way assembly of aero structures has the potential to significantly reduce build times. One of the solutions which goes towards achieving this philosophy is the use of a ‘C' clamping automated drilling system. The Manufacturing Technology Centre has developed, manufactured and tested a ‘C' clamping automated drilling unit to overcome many of the limitations of current designs which prevent their use on a broader range of structures. The drilling unit addresses issues with inter-stack burrs, access, size and the weight restrictions as well as economic factors. The technical paper will present the outcomes from the design and manufacture of the drilling unit that is to be used within restricted access areas as either a hand held device or as a robotic end effector, free from any cables or hoses, allowing full and unhindered articulation of any robot motion.
2017-09-19
Technical Paper
2017-01-2094
Tyler Everhart
Abstract Electroimpact, in collaboration with Boeing, has developed an advanced robotic assembly cell, dubbed “The Quadbots.” Using Electroimpact’s patented Accurate Robot technology and multi-function end effector (MFEE), each robot can drill, countersink, inspect hole quality, apply sealant, and insert fasteners into the part. The cell consists of 4 identical machines simultaneously working on a single section of the Boeing 787 fuselage, two on the left, and two on the right. These machines employ “collision avoidance” a new feature in their software to help them work more synchronously. The collision avoidance software uses positional feedback from external safety rated encoders mounted to the motors on the robot. From this feedback, safe spaces, in the form of virtual boundaries can be created. Such that a robot will stop and wait if the adjacent robot is in, or going to move into its programmed work envelope.
2017-09-19
Technical Paper
2017-01-2166
Hendrik Susemihl, Christoph Brillinger, Sven Philipp Stürmer, Stephan Hansen, Christian Boehlmann, Simon Kothe, Jörg Wollnack, Wolfgang Hintze
Internationally growing flight and passenger numbers have led to a joined order backlog of Airbus and Boeing of approx. 12,500 aircrafts. With today’s production rates the delivery of all aircrafts would take 8.5 years. The resulting endeavor for higher productivity requests more flexible manufacturing solutions. A bottleneck in production is the machining of large aircraft components. These components are commonly machined by vast portal machines. Due to time-consuming referencing processes, cost-effectiveness of these high-invest-machines is often non-satisfying. Mobile robots already have proven their advantages for drilling and fastening applications performing short, high-accuracy movements. With mobile robot-based solutions machining processes can be executed simultaneously which increases the productivity significantly. However, machining paths often have the same dimension as the component itself.
2017-09-19
Journal Article
2017-01-2165
Christian Moeller, Hans Christian Schmidt, Philip Koch, Christian Boehlmann, Simon Kothe, Jörg Wollnack, Wolfgang Hintze
The high demand of efficient large scale machining operations by concurrently decreasing operating time and costs has led to an increasing usage of industrial robots in contrast to large scaled machining centers. The main disadvantage of industrial robots used for machining processes is their poor absolute accuracy, caused by the serial construction, resilience of gearings and sensitivity for temperature changes. Additionally high process forces that occur during machining of CFRP structures in aerospace industry lead to significant path errors due to low structural stiffness of the robot kinematic. These errors cannot be detected by means of motor encoders. That is why calibration processes and internal control laws have no effect on errors caused by elastic deformation. In this research paper an approach for increasing the absolute accuracy of an industrial milling robot with help of a laser tracker system during machining tasks will be presented.
2017-07-10
Technical Paper
2017-28-1931
Shaul Hameed Syed, K Rameshkumar
Abstract In this work an attempt is made to design and fabricate a low cost dynamometer for measuring cutting forces in three directions in a CNC vertical milling machine. The dynamometer is designed and fabricated to withstand load up to 5000 N along ‘X’, ‘Y’ and ‘Z’ axis. Milling dynamometer developed in this work, consists of four octagonal rings as an elastic member on which strain gauges are mounted for measuring the cutting forces. Suitable materials for the fixture and for the octagonal rings are chosen for constructing the dynamometer. Structural analysis has been carried out to check the safe design of the dynamometer assembly consisting of fixture and the octagonal rings for the maximum loading conditions. Static calibration of the dynamometer is carried out using slotted weight method by simulating the actual conditions. Calibration chart was prepared for three directions by relating load and corresponding strain.
2017-07-10
Technical Paper
2017-28-1964
Rajaganesh Ramamoorthy, T. Venkatesan, R. Rajendran
Abstract Machining of materials has received significant consideration due to the increasing use of machining processes in various industrial applications. In machining, the heat generated in the cutting zone during machining is critical in deciding the work piece quality. Lubricants are widely used to reduce the heat generation. Their usage poses threat to environment and health hazards. Hence, there is a need to identify eco-friendly and user-friendly alternatives to conventional cutting fluids. Modern tribology has facilitated the use of solid lubricants such as graphite, calcium fluoride, molybdenum disulphide, and boric acid as an alternative to cutting fluids in machining. Solid lubricant assisted machining is an environmental friendly clean technology for improving the surface quality of the machined work piece.
2017-07-10
Technical Paper
2017-28-1962
Pervaz Ahmed Mouda, H Siddhi Jailani
Abstract Cryogenic treatment is an ultra low temperature treatment technique. Effect of cryogenic treatment on properties of ferrous materials and alloys is well understood. Due to which, cryogenic treated materials are being used in various applications. One among them is Electro-Discharge Machining (EDM). In EDM, the replica of electrode is obtained on the work piece, during the process tool also worn out to certain extent. In order to reduce the tool wear rate cryogenic treatment can be applied to the tool material. In this paper, the effect of cryogenic treatment on electrode wear rate of electro-discharge machining for varied pulse ON time (EDM) was studied. The cryogenic treatment was applied to the copper electrode and the microstructure analysis was carried out using optical microscope. EDM experiment was conducted using untreated and cryogenic treated copper as electrode and High Speed Steel (HSS) as work piece. Electrical resistivity was also measured.
2017-07-10
Technical Paper
2017-28-1983
J Ronald Aseer, P Baskara Sethupathi, J. Chandradass, Renold Elsen
Abstract The utilization of unconventional machining methods such as electron beam machining, electrical discharge machinating, etc., have been increased in the manufacturing industry to create holes on the materials. In this paper, twist drill was used for drilling of Bahunia racemosa (BR)/ glass fiber composites and then the measurement of hole diameter error was analysed. The main objective was to establish a correlation between feed rate, cutting speed and drill tool with the induced hole diameter error in a composites. The drilling process was performed under various cutting speed, feed rates and different drilling tools with a point angle of 118°. A Coordinate measuring machine was used to examine the hole diameter error of drilling hole. Taguchi L9 (33) orthogonal array was used to determine the optimum levels of the parameters and analyze the effect of drilling parameters on hole diameter error.
2017-07-10
Technical Paper
2017-28-1987
Vigneshwaran K, Palanivendhan Murugadoss, K Gokul
Abstract The main objective is to Extraction of cellulose fibers using mechanical ball milling process and chemical treatment methods. The fibers are incorporated with an epoxy matrix to make composite plates. Mechanical properties such as tensile strength, flexural strength, and impact energy are evaluated. Ball milling is the mechanical extraction method of producing nano size powder. The increase in milling process results in the chance of occurring nanofibers. The ball milling process is carried out without any chemical treatment process. In chemical treatment methods, three different kinds of treatment are performed namely sodium hypochlorite, sulphuric acid and acetic acid. Using hand layup methods these fibers are incorporated into the epoxy matrix to fabricate composite plates. In my study nanosized fiber is not obtained, only 28 micron fibers are converted into 3-4 microns.
2017-06-26
Solution Notes
SN-0001
Automating a manufacturing process often comes with substantial investment or sustained operational costs of complex subsystems. But, by reducing complexity and using technologically mature components, it is possible to develop viable scaled and robust automated solutions. For the past several years, aerospace manufacturers have endeavored to automate manufacturing processes as much as possible for both production efficiencies and competitive advantage. Automating processes like drilling, fastening, sealing, painting, and composite material production have reaped a wide range of benefits; from improving quality and productivity to lowering worker ergonomic risks. The results have improved supply chains from small component manufacturers all the way up to airframe assemblers. That said, automation can be very expensive, and difficult to introduce when a product is anywhere beyond the beginning of its life cycle.
2017-03-28
Technical Paper
2017-01-1625
Rajeev Kalamdani, Chandra Jalluri, Stephen Hermiller, Robert Clifton
Abstract Use of sensors to monitor dynamic performance of machine tools at Ford’s powertrain machining plants has proven to be effective. The traditional approach to convert sensor data to actionable intelligence consists of identifying single features from cycle based signatures and setting thresholds above acceptable performance limits based on trials. The thresholds are used to discriminate between acceptable and unacceptable performance during each cycle and raise alarms if necessary. This approach requires a significant amount of resource & time intensive set up work up-front and considerable trial and error adjustments. The current state does not leverage patterns that might be discernible using multiple features simultaneously. This paper describes enhanced methods for processing the data using supervised and unsupervised machine learning methods. The objective of using these methods is to improve the prediction accuracy and reduce up-front set up.
2017-03-28
Journal Article
2017-01-1330
Youssef Ziada, Juhchin Yang, David DeGroat-Ives
Abstract Owing to decreased development cycle timing, designing components for manufacturability has never been as important. Assessing manufacturing feasibility has therefore become an increasingly important part of new product engineering. This manufacturing feasibility is conventionally assessed based on static stiffness of components and fixture assemblies. However, in many operations, excess vibration represents the actual limitation on processing a workpiece. Limits on how far into components a tool can reach or the amount of processing time required to machine a feature is commonly decreased significantly due to vibration. Critical time is spent resolving these vibration problems during product launches. Depending on the machining configurations these vibrations can be due to the part & work support structure or due to the tooling & spindle assembly.
2017-03-28
Journal Article
2017-01-0400
Theo Rickert
Abstract Hole drilling is a very common technique for measuring residual stresses. Adding an orbiting motion of the drill was found to improve hole quality in difficult to drill materials and has been in practice for decades. This study compares measurements using various orbiting amounts. Each measurement was repeated twice to evaluate measurement statistics. There is a distinct, though relatively small, effect of the hole shape when no orbiting is used. It disappears already when the hole is 50% larger than the tool size. Different orbiting amounts also produce systematically different results. These may be related to the absolute hole size.
2016-09-27
Technical Paper
2016-01-2108
Marc Fette, Kim Schwake, Jens Wulfsberg, Frank Neuhaus, Manila Brandt
Abstract The rising demand for civil aircraft leads to the development of flexible and adaptive production systems in aviation industry. Due to economic efficiency, operational accuracy and high performance these manufacturing and assembly systems must be technologically robust and standardized. The current aircraft assembly and its jigs are characterized by a high complexity with poor changeability and low adaptability. In this context, the use of industrial robots and standardized jigs promise highly flexible and accurate complex assembly operations. This paper deals with the flexible and adaptable aircraft assembly based on industrial robots with special end-effectors for shaping operations. By the development and use of lightweight gripper system made of carbon fiber reinforced plastics the required scaling, robustness and stiffness of the whole assembly system can be realized.
2016-09-27
Technical Paper
2016-01-2110
Ilker Erdem, Peter Helgosson, Ashwin Gomes, Magnus Engstrom
Abstract The ability to adapt to rapidly evolving market demands continues to be the one of the key challenges in the automation of assembly processes in the aerospace industry. To meet this challenge, industry and academia have made efforts to automate flexible fixturing. LOCOMACHS (Low Cost Manufacturing and Assembly of Composite and Hybrid Structures) - a European Union funded project with 31 partners - aims to address various aspects of aero-structure assembly with a special attention directed to the development of a new build philosophy along with relevant enabling technologies. This paper aims to present the results on the developed wing box build philosophy and the integration of automated flexible tooling solutions into the assembly process. The developed solution constitutes the use of synchronized hexapods for the assembly of front spar to upper cover whereas another hexapod was developed to install a rib by using of a force feedback sensor.
2016-09-27
Technical Paper
2016-01-2107
Rainer Mueller, Matthias Vette, Matthias Scholer, Jan Ball
Abstract The global competition challenges aircraft manufactures in high wage countries. The assembly of large components is very difficult and distinguished by fixed position assembly. Many complex assembly processes such as aircraft assembly are manually done by highly skilled workers. The aircraft manufactures deal with a varying number of items, increasing number of product variants and strict product requirements. During the assembly process hundreds of clips, ties and stringers as well as thousands of rivets must be assembled. To remain competitive in global competition, companies in high wage countries like Germany must insure a continuously high productivity and quality level. To achieve a reduction of cycle times with a simultaneous increase in quality, supportive assistance systems for visual support, documentation and organization within the assembly are required. One example for visual assistance systems are laser projection systems.
2016-09-27
Technical Paper
2016-01-2109
Michael Morgan, Caroline McClory, Colm Higgins, Yan Jin, Adrian Murphy
Aerospace structures are typically joined to form larger assemblies using screw lock or swage lock fasteners or rivets. Countersunk fasteners are used widely in the aerospace industry on flying surfaces to reduce excrescence drag and increase aircraft performance. These fasteners are typically installed to a nominal countersink value which leaves them flush to the surface before being locked into position. The Northern Ireland Technology Centre (NITC) at Queen’s University Belfast has developed and demonstrated two processes which enable high tolerance flush fastening of countersunk fasteners: The ‘Flush Install’ process produces countersunk holes based on the specific geometry of each individual fastener; The ‘Fettle Flush’ process accurately machines fasteners to match the surrounding surface. Flushness values well within the allowable tolerances have been demonstrated for both Flush Install and Fettle Flush processes.
2016-09-27
Technical Paper
2016-01-2106
Dan R.W. Vaughan, Otto J. Bakker, David Branson, Svetan Ratchev
Abstract Aircraft manufacturers desire to increase production to keep up with anticipated demand. To achieve this, the aerospace industry requires a significant increase in the manufacturing and assembly performance to reach required output levels. This work therefore introduces the Variation Aware Assembly (VAA) concept and identifies its suitability for implementation into aircraft wing assembly processes. The VAA system concept focuses on achieving assemblies towards the nominal dimensions, as opposed to traditional tooling methods that aim to achieve assemblies anywhere within the tolerance band. It enables control of the variation found in Key Characteristics (KC) that will allow for an increase in the assembly quality and product performance. The concept consists of utilizing metrology data from sources both before and during the assembly process, to precisely position parts using motion controllers.
2016-09-27
Technical Paper
2016-01-2097
Sylvain Laporte, Cosme De Castelbajac, Mathieu Ladonne
Abstract The Vibration Assisted Drilling (VAD) process has been implemented in Automated Drilling Equipment (ADE) on an industrial scale since 2011. Today more than 11000 ADEs are currently used on aircraft assembly lines. As well as drawing up a short report on the use of this new process, the authors make an assessment on new challenges that VAD has to face up. Indeed production rates are increasing and ADE manufacturers improve their technologies, one of the most recent and major development concerning the electrical motorization of the machines. These evolutions are as many opportunities for the VAD provided you have a clever understanding as well as an expert knowledge of the process. Thus the authors propose a new dynamic model of the whole VAD system which integrates the behavior of the part, cutting tool/material pair and the machine. The confrontation of model results and experimental validation tests demonstrates the relevance of the works.
2016-09-27
Technical Paper
2016-01-2101
Burak Deger, Fazli Melemez, Aykut Kibar lng
Abstract A hybrid drilling process of multi material stacks with one shot drilling recently emerge as an economical and time efficient method in aerospace industry. Even though the comprehensive experience and knowledge is available for the cutting parameters of composites and metals alone, significant gap exist for the hybrid drilling parameters. Determination of these parameters such as feed rate, spindle speed and pecking depth has vital importance so as to provide a robust and optimal process to ensure dimensionally high quality, burr and delamination free holes. Main challenge of hybrid drilling operation is to obtain required hole diameter with adequate homogeneity and repeatability. In this study, effect of cutting parameters on dimensional hole quality was investigated. In addition to the hole diameter tolerances, CFRP hole enlargement phenomena which is encountered as a specific drawback of metal-exit stack configurations is also addressed within the scope of this study.
2016-09-27
Technical Paper
2016-01-2099
Peter Mueller-Hummel, Thomas Langhorst
Abstract On CNC Machines, drilling holes under perfect condition is possible. For drilling holes into titanium, composite and aluminum stacked materials the specific cutting condition can be selected. Furthermore surrounding conditions such as peck cycle, MQL and force and torque monitoring can be easily adapted. When drilling holes in the final assembly, CNC machine tools cannot be employed due to sizes and accessibility. Power Feed Units or Automated Drill Units ADUs are very handy, flexible and depending upon the jig extremely rigid. Whenever a machine tool does not fit, ADUs are highly recommended. In comparison to machine tools, conventional pneumatic ADUs can be used with one fixed set of feed, speed and micro peck only. Due to that a compromise in cutting condition has to be chosen in drilling stacked material with different layers.
2016-09-27
Technical Paper
2016-01-2091
Raul Cano, Oscar Ibanez de Garayo, Miguel Angel Castillo, Ricardo Marin, Hector Ascorbe, Jose Ramon de los Santos
Abstract The aim of this paper is to present a robust and low-cost automatic system for drilling aluminum stacks, as well as an integral methodology for the design of tool trajectories and the control of the drilling process itself. The proposed system employs a high accuracy robotic arm, a commercial spindle head and a specially developed SCADA, which enables it to load tool trajectories designed by using any software application. Furthermore, this SCADA is useful to monitor the main parameters of the drilling process for anticipating problems related to the unexpected tool wear or for a quick response in case of tool collision. A special jig for positioning the stack to be drilled is designed to increase the robot accessibility. In this work, tests are performed for optimizing the cutting parameters of the robotic system in order to maximize the accuracy and the surface finishing of the holes.
2016-09-27
Technical Paper
2016-01-2096
Simon Schnieders, Dirk Eickhorst
Abstract Drilling of high-strength titan material and composites in combination creates complex challenges in order to achieve required productivity and quality. Long spiral chips are characteristically for the titan drilling process, which leads to e.g. chip accumulation, high thermomechanical load, surface damages and excessive tool wear. The basic approach is the substitution of today’s peck drilling as current solution to this problem and the implementation of a vibration assisted drilling, so called micro-peck-drilling-process, to generate a kinematic chip breakage in a significant more efficient way. To meet perfectly the requirements regarding rates, quality and automation level, Broetje-Automation as system integrator has investigated and developed the implementation of different alternative high-performance systems and methods to approach the optimal oscillation movement of the tool.
2016-09-27
Technical Paper
2016-01-2095
Agata Suwala, Lucy Agyepong, Andrew Silcox
Abstract Reduction of overall drag to improve aircraft performance has always been one of the goals for aircraft manufacturers. One of the key contributors to decreasing drag is achieving laminar flow on a large proportion of the wing. Laminar flow requires parts to be manufactured and assembled within tighter tolerance bands than current build processes. Drilling of aircraft wings to the tolerances demanded by laminar flow requires machines with the stiffness and accuracy of a CNC machine while having the flexibility and envelope of an articulated arm. This paper describes the development and evaluation of high accuracy automated processes to enable the assembly of a one-off innovative laminar flow wing concept. This project is a continuation of a previously published SAE paper related to the development of advanced thermally stable and lightweight assembly fixture required to maintain laminar flow tolerances.
2016-09-27
Technical Paper
2016-01-2136
Oliver Pecat, Tebbe Paulsen, Philipp Katthöfer, Ekkard Brinksmeier, Sascha Fangmann
Abstract Insufficient chip extraction often leads to disruptions of automated drilling processes and will have a negative impact on the surface qualities. One opportunity to avoid chip accumulation is based on a kinematically enforced chip breakage caused by sinusoidal axial oscillations of the drilling tool. Recent investigations have shown that the quality of chip extraction is, amongst others, considerably depending on the chip shape and mass which are defined by the cutting parameters feed, amplitude and frequency. So far only mechanical systems in the form of tool holders have been available on the market, which are restricted to a fixed frequency (oscillation frequency is coupled to the spindle speed). In the present study a spindle with magnetic bearings was used which allows to adjust the oscillation frequency independent of the spindle speed and therefore enables all opportunities to affect the generated chip shapes.
Viewing 1 to 30 of 572

Filter

Subtopics