An integrated trajectory smoothing method for lines and arcs mixed toolpath based on motion overlapping strategy

Smoothing the discretized toolpaths generated by CAM systems is vital for CNC options in improving the quality of machined surfaces. One discretized toolpath from CAM is commonly represented in the form of a series of linear and arc segments. The linear segment smoothing method has been extensively investigated. However, for linear and arc joint segments, which are in the form of G01 and G02/03 mixing modes, efficient smoothing strategies are still lacking. In this study, an integrated toolpath smoothing method based on motion overlapping strategy is proposed to improve the continuities of the mixture of G01 and G02/03 codes. To satisfy the requests of the kinematic limitations and high efficiency, heuristic algorithms are used to seek optimum kinematic parameters. Meanwhile, we also introduce a variable jerk-limited feedrate profile in the motion overlapping strategy to further reduce the machining time. Simulations on various toolpaths are performed to validate the effectiveness of the proposed method compared with the classical FIR and B-spline methods. The machining experiment executed on a 3-axis machine tool with a real-time CNC system also demonstrates the applicability of the proposed method.