公开(公告)号：US11188056B2

公开(公告)日：2021-11-30

申请号：US16322290

申请日：2018-01-07

Applicant: Dalian University of Technology

Inventor： Zhenyuan Jia ,  Jianwei Ma ,  Dening Song ,  Siyu Chen ,  Guangzhi He ,  Fuji Wang ,  Wei Liu

IPC: G05B19/416

Abstract: This invention, a feedrate scheduling method for five-axis dual-spline curve interpolation, belongs to multi-axis NC (Numerical Control) machining filed, featured a feedrate scheduling method with constant speed at feedrate-sensitive regions under axial drive constraints for five-axis dual-spline interpolation. This method first discretizes the tool-tip spline with equal arc length, thus getting the relation between the axial motion and the toolpath by computing the first, second, and third order derivatives of the axial positions with respect to the tool-tip motion arc length. After that, determine the feedrate-sensitive regions with the constraints of axial drive limitations and the objective of balanced machining quality and efficiency. Finally, determine the acceleration/deceleration-start-point curve parameters by bi-directional scanning. The invented method can effectively make a balance between the feed motion stability and efficiency in five-axis machining, and possesses a high computational efficiency and a good real-time capability.

公开(公告)号：US10921772B2

公开(公告)日：2021-02-16

申请号：US16311922

申请日：2018-01-07

Applicant: Dalian University of Technology

Inventor： Jianwei Ma ,  Zhenyuan Jia ,  Dening Song ,  Fuji Wang ,  Wei Liu ,  Ning Zhang ,  Siyu Chen ,  Guangzhi He

IPC: G05B19/19 ,  G05B11/42

Abstract: The invented equivalent-plane cross-coupling control method belongs to high-precision and high-efficiency intelligent multi-axis CNC (Computer Numerical Control) machining filed, featured a three-axis cross-coupling controller based on the equivalent plane which can be used for improvement of the three-dimensional contour-following accuracy. This method first find the foot point from the actual motion position to the desired contour using a tangential back stepping based Newton method. Then, establish an equivalent plane which containing the spatial contouring-error vector by passing through the actual motion position and the tangential line at the foot point. After that, estimate the three-dimensional contouring error in a scalar form, thus controlling the signed error using a PID based two-axis cross-coupling controller. Finally, calculate the three-axis control signals according to the geometry of the equivalent plane, thus realizing the three-axis contouring-error control by using the well-studied two-axis contour controllers.