Benefits of Numerical Optimization and CAD/CAM in Needle Winding Processes

Abstract

One of the major benefits of the needle winding technology is its ability to flexibly produce different stators and rotors with the same machine. This advantage is oftentimes lost by time consuming, manual programming, which needs several iterations to result in a near optimal trajectory. The different needle winding kinematics are comparable to NC machines or multi-axes robots though, which allows to use intelligent trajectory planning algorithms. The overall goal of winding technologies is to achieve high quality coils with maximized copper filling factor. By applying numerical optimization methods and a CAD/CAM-like tool chain, near-ideal winding trajectories were generated automatically. Additionally, a study was given that investigates design considerations for a maximized copper filling factor using needle winding technology. Result of such a combined slot and winding parameter optimization are reference points that were taken to generate a smooth path consisting of basic NURBS entities. This path can be used for collision control with standard CAM tools as well. A feed rate optimization linked the path with the time and resulted in a near time optimal winding trajectory. The presented algorithm allowed to greatly lower the effort for implementing new trajectories. The resulting trajectories were evaluated for stators and rotors using an industrial winding machine.