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In the truck industry there is a continuous demand to increase the efficiency and to decrease the emissions. To acknowledge both these issues a waste heat recovery system (WHR) is combined with a partially premixed combustion (PPC) engine to deliver an efficient engine system. Over the past decades numerous attempts to increase the thermal efficiency of the diesel engine has been made. One such attempt is the PPC concept that has demonstrated potential for substantially increased thermal efficiency combined with much reduced emission levels. So far most work on increasing engine efficiency has been focused on improving the thermal efficiency of the engine while WHR, which has an excellent potential for another 1-5 % fuel consumption reduction, has not been researched that much yet. In this paper a WHR system using a Rankine cycle has been developed in a modeling environment using IPSEpro.

This paper offers a two-zone NOx model suitable for vehicle on-board, on-line implementation. Similar NOx modeling attempts have previously been undertaken. The hereby suggested method does however offer clear and important benefits over the previously methods, utilizing a significantly different method to handle temperature calculations within the (two) different zones avoiding iterative computation. The new method significantly improves calculation speed and, most important of all, reduces implementation complexity while still maintaining reasonable accuracy and the physical interpretation of earlier suggested methods. The equations commonly used to compute NOx emissions is also rewritten in order to suit a two-zone NOx model. An algorithm which can be used to compute NOx emissions is presented and the intended contribution of the paper is a NOx model, implementation feasible for an embedded system, e.g. embedded processor or embedded electronic hardware (FPGA).

In the civil aircraft industry there is a continuous drive to increase the aircraft production rate, particularly for single aisle aircraft where there is a large backlog of orders. One of the bottlenecks is the wing assembly process which is largely manual due to the complexity of the task and the limited accessibility. The presented work describes a general wing build approach for both structure and systems equipping operations. A modified build philosophy is then proposed, concerned with large component pre-equipping, such as skins, spars or ribs. The approach benefits from an offloading of the systems equipping phase and allowing for higher flexibility to organize the pre-equipping stations as separate entities from the overall production line. Its application is presented in the context of an industrial project focused on selecting feasible system candidates for a fixed wing design, based on assembly consideration risks for tooling, interference and access.

This paper describes and demonstrates the use of an assembly centric design algorithm as an aid to achieving minimal hard tooling assembly concepts. The algorithm consists of a number of logically ordered design methodologies and also aids the identification of other enabling technologies. Included in the methodologies is an innovative systems analysis tool that enables the comparison of alternative assembly concepts, and the prediction and control of the total assembly error, at the outline stage of the design.

The local equivalence ratio, Φ, was measured in fuel jets using laser-induced spontaneous Raman scattering in an optical heavy duty diesel engine. The measurements were performed at 1200 rpm and quarter load (6 bar IMEP). The objective was to study factors influencing soot formation, such as gas entrainment and lift-off position, and to find correlations with engine-out particulate matter (PM) levels. The effects of nozzle hole size, injection pressure, inlet oxygen concentration, and ambient density at TDC were studied. The position of the lift–off region was determined from OH chemiluminescence images of the flame. The liquid penetration length was measured with Mie scattering to ensure that the Raman measurement was performed in the gaseous part of the spray. The local Φ value was successfully measured inside a fuel jet. A surprisingly low correlation coefficient between engine-out PM and the local Φ in the reaction zone were observed.

On Airbus aircraft, the undercarriage reinforcing is attached through the lower wing skin using bolts up to 1-inch in diameter through as much as a 4-inch stack up. This operation typically takes place in the wing box assembly jigs. Manual hole drilling for these bolts has traditionally required massive drill templates and large positive feed drill motors. In spite of these large tools, the holes must be drilled in multiple steps to reduce the thrust loads, which adds process time. For the new A380, Airbus UK wanted to explore a more efficient method of drilling these large diameter holes. Introducing automated drilling equipment, which is capable of drilling these holes and still allows for the required manual access within the wing box assembly jig, was a significant challenge. To remain cost effective, the equipment must be flexible and mobile, a llowing it to be used on multiple assemblies.

A consortium of interested parties has conducted an experimental characterization of two Tau parallel kinematic machines which were built as a part of the EU-funded project, SMErobot1. Characteristics such as machine stiffness, work envelope, repeatability and accuracy were considered. This paper will present a brief history of the Tau parallel machine, the results of this testing and some comment on prospective application to the aerospace industry.

A custom 5-axis machine tool is constructed to enable fully automated drilling and slave-bolt insertion of composite and metallic wingbox components for a new military transport aircraft. The machine tool can be transported to serve many assembly jigs within the cell. Several features enhance accuracy, capability, and operator safety.

The objective of this paper is to investigate whether different appearance modes of the digital human models (DHM or manikins) affect the observers when judging a working posture. A case where the manikin is manually assembling a battery in the boot with help of a lifting device is used in the experiment. 16 different pictures were created and presented for the subjects. All pictures have the same background, but include a unique posture and manikin appearance combination. Four postures and four manikin appearances were used. The subjects were asked to rank the pictures after ergonomic assessment based on posture of the manikin. Subjects taking part in the study were either manufacturing engineering managers, simulation engineers or ergonomists. Results show that the different appearance modes affect the ergonomic judgment. A more realistic looking manikin is rated higher than the very same posture visualized with a less natural appearance.

The paper describes a way of generating a cost model, which is aimed to compare different drilling processes. The development of this tool is a part of an ongoing European Union funded aircraft industry project called ADFAST (Automation for Drilling, Fastening, Assembly, Systems Integration, and Tooling). This part of the project involves 4 industrial partners, (Alenia, Airbus Espana SL, Airbus UK and Saab AB), 1 equipment developer (Novator AB) and 1 academic institute (Linkoping University). The model has been created to enable the benefits of an advanced system such as orbital drilling to be quantified. The model is able to generate a cycle time and a cost for the whole drilling process involving equipment, consumables and assembly of varied aircraft structures. The challenge of the task was to develop the ability of modeling a process with a sequence of drilling operations that the model user, in an intuitive way, can select and modify.

With increased demand for composite materials in the aerospace sector there is a requirement for the development of manufacturing processes that enable larger and more complex geometries, whilst ensuring that the functionality and specific properties of the component are maintained. To achieve this, methods such as thermal roll forming are being considered. This method is relatively new to composite forming in the aerospace field, and as such there are currently issues with the formation of part defects during manufacture. Previous work has shown that precise control of the force applied to the composite surface during forming has the potential to prevent the formation of wrinkle defects. In this paper the development of various control strategies that can robustly adapt to different complex geometries are presented and compared within simulated and small scale experimental environments, on varying surface profiles.

Automation in aerospace industry is often in the form of dedicated solutions and focused on processes like drilling, riveting etc. The common industrial robot has due to limitations in positional accuracy and stiffness often been unsuitable for aerospace manufacturing. One major cost driver in aircraft manufacturing is manual assembly and the bespoke tooling needed. Assembly tasks frequently involve setting relations between parts rather than a global need for accuracy. This makes assembly a suitable process for the use of force control. With force control a robot equipped with needed software and hardware, searches for desired force rather than for a position. To test the usefulness of force control for aircraft assembly an experimental case aligning a compliant rib to multiple surfaces was designed and executed. The system used consisted of a standard ABB robot and an open controller and the assembly sequence was made up of several steps in order to achieve final position.

Variability in composite manufacture and the limitations in positional accuracy of common industrial robots have hampered automation of assembly tasks within aircraft manufacturing. One way to handle geometry variations and robot compliancy is to use force control. Force control technology utilizes a sensor mounted on the robot to feedback force data to the controller system so instead of being position driven, i.e. programmed to achieve a certain position with the tool, the robot can be programmed to achieve a certain force. This paper presents an experimental case where a compliant rib is aligned to multiple surfaces using force feedback and an industrial robot system from ABB. Two types of ribs where used, one full size carbon fiber rib, and one smaller metal replica for evaluation purposes. The alignment sequence consisted of several iterative steps and a search procedure was implemented within the robot control system.

This paper details the development of a user-friendly computerised tool created to evaluate the Manufacturing Readiness Levels (MRL) of an emerging technology. The main benefits achieved are to manage technology development planning and tracking, make visually clear and standardised analysis, and improve team communication. The new approach is applied to the Technology Readiness Levels (TRL), currently used by Airbus Research & Technology (R&T) UK. The main focus is on the improvement of the analysis criteria. The first phase of the study was to interpret the manufacturing criteria used by Airbus at TRL 4, including a brief benchmarking review of similar practices in industry and other Airbus' project management tools. All information gathered contributed to the creation of a complete set of criteria.

In the study presented in this paper a single-cylinder Scania D12 diesel engine has been converted to work as a pneumatic hybrid. During pneumatic hybrid operation the engine can be used as a 2-stroke compressor for generation of compressed air during vehicle deceleration and during vehicle acceleration the engine can be operated as an air-motor driven by the previously stored pressurized air. The compressed air is stored in a pressure tank connected to one of the inlet ports. One of the engine inlet valves has been modified to work as a tank valve in order to control the pressurized air flow to and from the pressure tank. In order to switch between different modes of engine operation there is a need for a VVT system and the engine used in this study is equipped with pneumatic valve actuators that uses compressed air in order to drive the valves and the motion of the valves are controlled by a combination of electronics and hydraulics.

The Airbus A400m has carbon fibre wing panels on both the upper and lower surfaces. When manufactured, these panels come supplied with various lugs on the periphery of the panel. Some are used for lifting the panel, some are used for indexing the panel; however, all lugs must be removed at some time during wing build. Lug thickness varies from 4mm to 14mm; in addition, many lugs must be cut to a 2D profile rather than just straight. The main challenge of the project was to deliver a tool that was small, portable and compact, but that could also accurately slot thick carbon fibre panels, without de-lamination, leaving a good surface finish. The solution was an air powered routing hand tool that was mechanically guided along a 2D path using a cam profile. Special diamond grit cutters were used to cut the initial slot and reduce the machining forces to a bare minimum, with the finishing cut done using a PCD router bit to obtain a good surface finish.

This paper will present the latest development of a configurable and modular steel construction system for use in frameworks of flexible fixtures of the kind called Affordable Reconfigurable Fixtures (ART). Instead of a dedicated aircraft fixture, which is very time consuming and expensive, the ART fixtures enable affordable construction from a standard component kit, by solving the main drawbacks of traditional tooling. In early 2009 Airbus UK built the first steel modular fixture for the aerospace industry. The project was a partnership with DELFOi and Linköping University in a project called ReFlex, Reconfigurable Flexible Tooling. A paper was presented in the last year SAE conference which explained about the project in overall. The construction system called BoxJoint has recently been tested in some manufacturing areas at Airbus UK and also been applied in the production at Saab Aerospace Linköping Sweden.

This paper presents an innovative solution of portable drilling machine, lightweight and low cost, dedicated to drilling operations on single and double curved aircraft structure. Aircraft Standard drilling process mainly uses drilling templates combined with Automated Drilling Units (ADU) which is a very efficient solution. However, the management of templates and ADUs is a time consuming and costly task in regards to the large quantity of existing references spread over every aircraft production sites. Therefore, to help reducing those costs and also workload, the concept of the Numerical Template (NCT) has been designed, using classic and robust mechanical devices, hand-held, lightweight and universal. NCT architecture concept could led to a family of NCT with different dimensions of frame parts(X,Y,Z), fitted to the targeted area geometry. The system is able to guaranty an accuracy of ± 0.5 mm and a normality of ±0.5°.

Drilling is one of the most costly and labour-intensive operations in aircraft assembly. Rather than automating with expensive fixtures and precise machinery, our approach is to make use of standard low-cost robot equipment in combination with sensor feedback. The focus is to eliminate the sliding movement of the end-effector during the clamp-up, called the skating effect, and to keep the end-effector orthogonal to the surface, thus avoiding holes that are not perpendicular. To that end, force feedback is used for building up pressure to clamp up an end-effector to the work-piece surface prior to drilling. The system, including the planning of force parameters for each hole to be drilled, was programmed in DELMIA. The drilling was accomplished with the aid of an extension to the ABB Rapid language called ExtRapid, which is an XML-like code that is interpreted by the force feedback controller downstream in the process.

To date, the universal metric for road safety has been historical crash data, specifically, crash frequency and severity, which are direct measures of safety. However, there are well-recognized shortcomings of the crash-based approach; its greatest drawback being that it is reactive and requires long observational periods. Surrogate measures of safety, which encompass measures of safety that do not rely on crash data, have been proposed as a proactive approach to road safety analysis. This white paper provides an overview of the concept and evolution of surrogate measures of safety, as well as the emerging and future methods and measures. This is followed by the identification of the standards needs in this discipline as well as the scope of SAE’s Surrogate Measures of Safety Committee.