Computer Aided Filament Winding For Composite Joints

Filament winding is a production technique for manufacturing composites structures,which is produced by laying the impregnated fiber bundles on the mandrel along the prescribed path under the control of the pay-out eye.Furthermore,composites joints are an essential component of the pipeline system.This paper mainly studies the three commonly used composite joints: elbow tube,diameter-varying tube and rectangular tube.Using the constant angle winding curve proposed in this paper,combined with geodesic and semi-geodesic curve,we propose an integration design method.The specific research contents are as follows:1)Elbow tube is generally composed of toroid and cylinder.Existing winding methods typically use geodesics on the torus and semi-geodesics on the cylinder.In addition,there is few related work on winding patterns that makes fiber bands uniformly cover the elbow.This paper reveals the essential characteristic for uniform coverage of torus winding,and based on it,we design a new winding method using semi-geodesic or constant angle winding curves on torus and semi-geodesics on cylinder.Furthermore,we make the fiber distribution more uniform.This method can produce light elbows with balance hoop and axial stress.2)The traditional diameter-varying tube is composed of a cylinder and cone with a rough transition leading to stress concentration.This paper proposes a smooth diameter-varying tube consisting of cylinder and revolution surface with interpolation spline as meridian.In addition,this paper studies the geodesics,semi-geodesics and constant winding angle curves on the rotating surface,and presents the necessary and sufficient conditions for non-bridging and the condition for non-slipping of constant winding angle curves.Finally,this paper gives the winding method of stable and uniform coverage of the diameter-varying tube and develops a computer-aided design tool.3)This paper proposes a constant angle winding pattern,which is suitable for helical winding on rectangular tubes from 3° to nearly 90° winding angles.We proposes a new effective machine path generation method for four-axis winding machine.Our machine path generation method firstly projects each point of fibre paths onto an enveloping contour along its tangent direction,and then translates these mapping points on the enveloping surface into motion data of winding machine.We propose a new multi-axis synchronous motion algorithm for the synchronization problem of multiple motion axes in low angle winding.The algorithm plans the overall motion speed of the machine based on the incremental data of the machine path to ensure the synchronization of each axis’ s motion.Based on these principles and methods,we have developed a CAD/CAM software for filament winding on rectangular tubes.