Comparison and post-processing algorithm for 7 DOF fiber placement machine

In order to make 7 DOF fiber placement machine to move along the planned path, the post-processing algorithm must be studied. By analyzing various inverse solutions of 7 DOF redundant robots and the process of fiber placement, a pose-separated method is adopted in the post-processing. In this method, the seven joints are divided into two parts, the principle joints and the mechanical arm. The post-processing keeps the mechanism's redundancy, avoids the kinetic analysis and optimization, and simplifies the calculation. By analyzing different processing methods for the principle joints, both post-processing method based on the motion trajectory of the end of mechanical arms and post-processing method based on the pressure direction at the trajectory point are proposed. Compared above methods, it can be found that the latter method can make the motion of machine tools smooth, the ranges of joints small, the fluctuation of joint angles small. The post-processing method and pose-separated method are all verified by the placement simulation.