JEC COMPOSITES MAGAZINE - Issue #34 - July/August 2007 - 64

KNOW-HOW Software PC-FIL 22: software for coiling complexrevolution structures African farmers use baskets to transport foodstuffs from fields to home, to be stored in granary baskets. In response to the growing demand for such baskets, new software called PC-FIL22 has been developed to simulate the winding process on a computer screen and to prepare data for controlling a filament-winding machine. spreads the use of two-axis machines for helical winding of complex-revolution structures, without any restriction of the winding angle; this allows producing cheaper complexrevolution pieces. The two axes to be used are: 1) the mandrel axis of rotation and 2) the feed-eye translation axis. During coiling, the revolution mandrel turns around its axis while the feed eye is moving in translation parallel to that axis. At the end of the simulation process, the software generates a file where the control parameters of both the mandrel and the feed-eye positions are stored. Finally, it establishes a coil piloting program for the CYBER 3000 numerical control unit. 1- ATANGANA ATEBA, HEAD OF THE DEPARTMENT OF MECHANICS, ENSET 2- TIMBA SADRACK JEAN-PIERRE, LECTURER, ENSET 3- BETENE EBANDA FABIEN, ASSISTANT LECTURER, ENSET UNIVERSITY OF DOUALA, ECOLE NORMALE SUPÉRIEURE D’ENSEIGNEMENT TECHNIQUE, DOUALA, CAMEROON Filament winding of composite structures n Africa, food is transported from fields to family compounds in baskets. The groundnuts, cucumbers (or pistachios), cocoa, coffee, etc. are stored in granary baskets. Small baskets are used for handling food at home and can also be used as lampshades. In homes, housewives store clothes for washing or ironing in other types of baskets. I All these materials are produced manually by craftsmen and it generally takes days to produce a unit. The creeper used as raw materiel is becoming scarce: for example, you may have to walk up to ten kilometres in the bush to get the necessary quantity. The software presented in this paper will make it possible to control a winding machine that uses carbon and glass fibres impregnated with thermoplastic or thermosetting resins as raw material. Such a production chain can produce a large number of smaller baskets or granary baskets within an hour. The raw material used here considerably increases the durability of these containers. Simulation and control software The PC-FIL2.2 software is used to simulate the coiling of complex-revolution structures on a computer screen and to prepare a program for a numerical command unit controlling a two-axis winding machine. Since two-axis winding is generally adapted to polar and circumferential coiling, this software Manufacturing composite structures by filament winding involves three types of fibre winding patterns on the revolving mandrel: • polar (or semi-polar); • circumferential; • helical. The winding angle „ is defined as the sharp angle made by a mandrel meridian and the direction of the deposited ribbon. The winding is said to be polar (or semi-polar) when ψ < 15° and circumferential when ψ is close to 90°. For ψ values ranging from 15° to 80°, we talk of helical winding. In practice, polar and circumferential windings are easy to produce with two-axis machines whereas helical winding requires a minimum of three axes to improve ribbon placement on the mandrel, in all, respecting the geodesic trajectory [1]. Considering the fact that the cost of a machine increases with the number of axes, the aim of this study is to reduce the number of axes to a strict minimum while maintaining the service and performance level of multi-axis machines [2]. It should be emphasized that this type of simplified machine is better suited to wet coiling, where the ribbon passes through a container filled with resin in solution before coiling on the mandrel. The resulting structure is then placed inside a steam room under controlled temperature for polymerisation of the resin. The application can also coil additional pre-impregnated glass fibres using a hot-mandrel winding process. JEC Composites Magazine / No34 July-August 2007

JEC COMPOSITES MAGAZINE - Issue #34 - July/August 2007

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #34 - July/August 2007