The use of curvilinear fibre paths to develop variable stiffness laminates is now recognised as a promising technique offering great potential for performance improvements over conventional 'straight fibre' laminates. Its manufacture is feasible by fibre placement technologies, such as automated fibre placement. However, these technologies present a set of limitations that need to be included in the design to guarantee the manufacturability and quality of the composite laminates. Although this approach experiences an increasing interest from the specialised literature, most of the works completed overlook the manufacturing reality and, as a result, variable stiffness laminates are not used in industry. This work aims to provide a review of the State-of-the-Art on design for manufacture of variable stiffness in order to highlight the current gaps and research needs. As a conclusion, tools for analysis of the effect of manufacturing defects, manufacturing optimisation of gaps/overlaps or cycle time and the systematic integration of manufacturing constraints in design, are the main challenges that will be faced in the future to be able to exploit the potential of this advanced tailoring technique.

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When a composite laminate is tailored to suit its design intent, it is possible to improve the individual ply shapes to reduce component mass. If the laminate is going to be manufactured using an automated deposition system such as an automated fibre placement machine, then the design of the laminate will also influence the material deposition speed. This article identifies methodologies for indicating the likely impact on automated manufacture at the design optimisation stage by evaluating the ratio of ply perimeter to ply surface area when the laminate is defined as a simplified array of cells which are filled or unfilled to create a two-dimensional representation of the ply shape. A set of recommendations are made for using the methodology for improving deposition speed.

Energy efficiency has become a key concern in industry due to increased energy cost and associated environmental impacts. It is as well factor on marketing and reputation. Customers require information on the ecological performance of products and the process to build that product. Therefore ecoefficient manufacturing is in our days a matter of competitiveness and economic success. This paper presents industrial driven research and the key findings from production eco and energy efficiency analysis and development projects. Both static and dynamic multi-level modelling and simulation is covered with examples. The use of Value Stream Mapping and Discrete Event Simulation with life cycle inventory data for production eco efficiency analysis is explained. Generic developement steps for process, machine and production system model with environmantal aspects is shown. Development continues in EPES "Eco Process Engineering System for Composition of Services to Optimise Product Life-Cycle"-project.