Automated braiding of non-axisymmetric structures using an iterative inverse solution with angle control

Braiding reinforcing fibres into a shape using a mandrel is an efficient preforming method to produce composite products. Braiding consists of two yarn groups rotating and interlacing. Mechanical properties of the braided parts are related to the braiding angle, which is controlled by the take-off speed of the over-braided mandrel. This paper presents a novel approach to find the required speed profile to achieve the local targeted braiding angle. The proposed method computes the speed profile iteratively starting from an approximate model and correcting based on the results of the kinematic forward solution and feedback from actual angle measurements following actual braiding. Case studies have shown the validity of the approach for braiding on non-axisymmetric, curved, and variable cross-section mandrels. Implementation results have demonstrated that the proposed model lowers the error of the braid angle in every case, allowing the braid angle to be 1.0° off on average and even 0.7° off without outliers.