Lighting Emitting Diode (LED), a new generation semiconductor light source often referred to as Solid-State Lighting (SSL), has been broadly adopted in illumination, display, visualization, and other areas due to its higher efficacy and longer life. LEDs, first introduced for automotive interior applications such as indicators, expanded to exterior applications including center high mounted stop lamps and other automotive signal lighting devices. Today, LED technologies are being used for night vision, occupancy detection, and many other automotive application areas.
It has not been commonly known that automotive exterior lights are safety devices and must comply with governmental regulations. Since the 1930s, the SAE Lighting Standards Committee has been actively working with the automotive industry OEMs, lamp makers, tier-two suppliers, and human factor experts to develop automotive lighting standards. These standards have been widely used or referenced by the U.S. federal or state governments in establishing and enforcing the lighting regulations.
Since the invention of the automobile, lighting has been an important subsystem on all ground vehicles. Automotive lighting is vital to passenger safety, comfort and vehicle styling. The technology used in automotive lighting has rapidly expanded to make the lighting more value added, safer and pleasing to customers. This seminar provides broad information about automotive lighting systems with emphasis on lighting functions, effectiveness, and technologies. The intent is to assist attendees to gain sufficient knowledge about automotive lighting and its importance in overall vehicle design and development.
Aircraft manufacturers use adhesive bonded brackets (ABB) to support wire harnesses, looms and sensors. Using ABBs eliminates the necessity to drill holes in the airframe and significantly reduces the assembly time. Such brackets are installed manually on the airframes in numerous locations using high strength epoxy based adhesives. In addition, the application of adhesive onto bracket is carried out manually. Thus it's time consuming and quality relies on operator’s skill sets to apply a certain quantity of adhesive using a predefined pattern, both of which are commonly not controlled. On the other hand, removing the damaged brackets by manual operations tend to cause dents and scratches in metallic airframes and delamination in composites. Prior research indicates that the brackets can be removed by heating them. But, they are not recommendable to aerospace manufacturers due to the longer process times.
For aircraft structures, mechanical assembly using fasteners remains the most common technology. The setting of the numerous fasteners requires a large number of drilling operations. In the case of CFRP/TA6V stacks, the drilling still remains a technological challenge. Indeed the high-quality requirements by the aeronautic standards are limited by the fast damaging drilling tool phenomena. For TA6V, the forced assisted drilling provides a breakthrough technology. An axial forced oscillating displacement on the feed direction of the tool allows the creation of segmented chips. Those small chips are then easily evacuated from the cutting area using a vacuum device. This allows the improvement of the hole’s roughness and mastering the burr creation at the exit of the hole. The lubrication process is also enhanced during the exit sequence of the tool. For the CFRP/TA6V configuration, the segmented geometry of the chip avoids the roughness degradation on the composite part of the stack.
This paper documents the potential use of reconfigurable reusable jig tooling based on the box-joint system for use in the assembly of a prototype compound helicopter wing. Due to the aircraft configuration the wing design is pinned at both ends and therefore requires a higher degree of accuracy (typically 0.2mm), over the 4m length, than conventional wings. In this paper the cost benefit of reusable tooling in a low volume prototype scenario is examined followed by the design of the jig and location features to enable accurate build and metrology documentation. A prototype 4m test jig comprising of commercially available components and bespoke machined ‘pick-ups’ is presented here. Hardware and measurement process cost modelling is documented along with results for the positional and hinge-line concentricity setting accuracy that was achieved using a laser tracking system.
The paper presents the numerical approach to simulation and optimization of A350 S19 splice assembly process. The main goal is to reduce the number of installed temporary fasteners while preventing the gap between parts from opening during drilling stage. The numerical approach includes computation of residual gaps between parts, optimization of fastener pattern and validation of obtained solution on input data generated on the base of available measurements. The problem is solved with ASRP (Assembly Simulation of Riveting Process) software. The described methodology is applied to the optimization of the robotized assembly process for A350 S19 section.
The demonstrator project RACER is developed under the leadership of Airbus Helicopters Group within a large European partnership and concerns the development of new VTOL formula in order to fill the mobility gap between conventional helicopters and airplanes. Thus, RACER is a compound rotorcraft including wings and propellers. The new wing arrangement suggested by Airbus Helicopters Groups is defined as a staggered bi-plane configuration with an upper and a lower straight wing at each side of the helicopter, both being interconnected at their outermost tips, forming a triangular framework. Responsible for the design, manufacturing and assembly of the wings is ASTRAL consortium consisted of GE Aviation and University of Nottingham. The identification of the best strategy to assemble the joined wing configuration is quite challenging. In order to ensure that the final wing assembly will fit to the fuselage, a jig that simulates the fuselage was suggested by Airbus Helicopters Group.
ASRP (Assembly Simulation of Riveting Process) software is a special tool for modelling assembly process for large scale airframe parts. On the base of variation simulation, ASRP provides a convenient way to analyze, verify and optimize the arrangement of temporary fasteners. During the airframe assembly process certain criteria on the residual gap between parts must be fulfilled. The numerical approach realized in ASRP allows one to evaluate the quality of contact on every stage of the assembly process and solve verification and optimization problems for temporary fastener patterns. The paper is devoted to description of several specialized approaches that combine statistical analysis of measured data and numerical simulation using high-performance computing for optimization of fastener patterns, calculation of forces in fasteners needed to close initial gaps and identification of hazardous areas in junction regions.
The demanded development towards various emission reduction goals set up by several institutions forces the aerospace industry to think about new technologies and alternative aircraft configurations. With these alternative aircraft concepts, the landing gear layout is also affected. Turbofan engines with very high bypass ratios could increase the diameter of the nacelles extensively. In this case, mounting the engines above the wing could be a possible arrangement to avoid an exceedingly long landing gear. Thus, the landing gear could be shortened and eventually mounted at the fuselage instead of the wings. Other technologies such as high aspect ratio wings have an influence on the landing gear integration as well. To assess the difference, especially in weight, between the conventional landing gear configuration and alternative layouts a method is developed based on preliminary structural designs of the different aircraft components, namely landing gear, wing and fuselage.
Flow separation is among the major causes of aerodynamic drag experience by wings. Vortex generators are regularly used as a means of flow separation control in wings, their use leading to delayed flow separation and drag reduction. A disadvantage of external vortex generators has been observed to be high momentum loss and inefficiency in vortex generation. Internal vortex generators minimize the penalty of momentum loss and generate vortices closer to the surface. In this paper, the impact of the length of internal vortex generators on the aerodynamic characteristics of a wing have been investigated. Internal vortex generators have been placed at 30% chord distance on the suction side of a NACA 0012 airfoil. Analysis is carried out using the Computational Fluid Dynamics software ANSYS Fluent. The length of the vortex has been varied between H and 5H, H being the thickness of the boundary layer, at air flow Reynolds Number between 1,000,000 and 5,000,000.